drivers/char/ipmi/ipmi_msghandler.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * ipmi_msghandler.c
   4  *
   5  * Incoming and outgoing message routing for an IPMI interface.
   6  *
   7  * Author: MontaVista Software, Inc.
   8  *         Corey Minyard <minyard@mvista.com>
   9  *         source@mvista.com
  10  *
  11  * Copyright 2002 MontaVista Software Inc.
  12  */
  13
  14 #define pr_fmt(fmt) "%s" fmt, "IPMI message handler: "
  15 #define dev_fmt pr_fmt
  16
  17 #include <linux/module.h>
  18 #include <linux/errno.h>
  19 #include <linux/poll.h>
  20 #include <linux/sched.h>
  21 #include <linux/seq_file.h>
  22 #include <linux/spinlock.h>
  23 #include <linux/mutex.h>
  24 #include <linux/slab.h>
  25 #include <linux/ipmi.h>
  26 #include <linux/ipmi_smi.h>
  27 #include <linux/notifier.h>
  28 #include <linux/init.h>
  29 #include <linux/proc_fs.h>
  30 #include <linux/rcupdate.h>
  31 #include <linux/interrupt.h>
  32 #include <linux/moduleparam.h>
  33 #include <linux/workqueue.h>
  34 #include <linux/uuid.h>
  35 #include <linux/nospec.h>
  36 #include <linux/vmalloc.h>
  37 #include <linux/delay.h>
  38
  39 #define IPMI_DRIVER_VERSION "39.2"
  40
  41 static struct ipmi_recv_msg *ipmi_alloc_recv_msg(void);
  42 static int ipmi_init_msghandler(void);
  43 static void smi_recv_tasklet(struct tasklet_struct *t);
  44 static void handle_new_recv_msgs(struct ipmi_smi *intf);
  45 static void need_waiter(struct ipmi_smi *intf);
  46 static int handle_one_recv_msg(struct ipmi_smi *intf,
  47                                struct ipmi_smi_msg *msg);
  48
  49 static bool initialized;
  50 static bool drvregistered;
  51
  52 enum ipmi_panic_event_op {
  53         IPMI_SEND_PANIC_EVENT_NONE,
  54         IPMI_SEND_PANIC_EVENT,
  55         IPMI_SEND_PANIC_EVENT_STRING
  56 };
  57 #ifdef CONFIG_IPMI_PANIC_STRING
  58 #define IPMI_PANIC_DEFAULT IPMI_SEND_PANIC_EVENT_STRING
  59 #elif defined(CONFIG_IPMI_PANIC_EVENT)
  60 #define IPMI_PANIC_DEFAULT IPMI_SEND_PANIC_EVENT
  61 #else
  62 #define IPMI_PANIC_DEFAULT IPMI_SEND_PANIC_EVENT_NONE
  63 #endif
  64
  65 static enum ipmi_panic_event_op ipmi_send_panic_event = IPMI_PANIC_DEFAULT;
  66
  67 static int panic_op_write_handler(const char *val,
  68                                   const struct kernel_param *kp)
  69 {
  70         char valcp[16];
  71         char *s;
  72
  73         strncpy(valcp, val, 15);
  74         valcp[15] = '\0';
  75
  76         s = strstrip(valcp);
  77
  78         if (strcmp(s, "none") == 0)
  79                 ipmi_send_panic_event = IPMI_SEND_PANIC_EVENT_NONE;
  80         else if (strcmp(s, "event") == 0)
  81                 ipmi_send_panic_event = IPMI_SEND_PANIC_EVENT;
  82         else if (strcmp(s, "string") == 0)
  83                 ipmi_send_panic_event = IPMI_SEND_PANIC_EVENT_STRING;
  84         else
  85                 return -EINVAL;
  86
  87         return 0;
  88 }
  89
  90 static int panic_op_read_handler(char *buffer, const struct kernel_param *kp)
  91 {
  92         switch (ipmi_send_panic_event) {
  93         case IPMI_SEND_PANIC_EVENT_NONE:
  94                 strcpy(buffer, "none\n");
  95                 break;
  96
  97         case IPMI_SEND_PANIC_EVENT:
  98                 strcpy(buffer, "event\n");
  99                 break;
 100
 101         case IPMI_SEND_PANIC_EVENT_STRING:
 102                 strcpy(buffer, "string\n");
 103                 break;
 104
 105         default:
 106                 strcpy(buffer, "???\n");
 107                 break;
 108         }
 109
 110         return strlen(buffer);
 111 }
 112
 113 static const struct kernel_param_ops panic_op_ops = {
 114         .set = panic_op_write_handler,
 115         .get = panic_op_read_handler
 116 };
 117 module_param_cb(panic_op, &panic_op_ops, NULL, 0600);
 118 MODULE_PARM_DESC(panic_op, "Sets if the IPMI driver will attempt to store panic information in the event log in the event of a panic.  Set to 'none' for no, 'event' for a single event, or 'string' for a generic event and the panic string in IPMI OEM events.");
 119
 120
 121 #define MAX_EVENTS_IN_QUEUE     25
 122
 123 /* Remain in auto-maintenance mode for this amount of time (in ms). */
 124 static unsigned long maintenance_mode_timeout_ms = 30000;
 125 module_param(maintenance_mode_timeout_ms, ulong, 0644);
 126 MODULE_PARM_DESC(maintenance_mode_timeout_ms,
 127                  "The time (milliseconds) after the last maintenance message that the connection stays in maintenance mode.");
 128
 129 /*
 130  * Don't let a message sit in a queue forever, always time it with at lest
 131  * the max message timer.  This is in milliseconds.
 132  */
 133 #define MAX_MSG_TIMEOUT         60000
 134
 135 /*
 136  * Timeout times below are in milliseconds, and are done off a 1
 137  * second timer.  So setting the value to 1000 would mean anything
 138  * between 0 and 1000ms.  So really the only reasonable minimum
 139  * setting it 2000ms, which is between 1 and 2 seconds.
 140  */
 141
 142 /* The default timeout for message retries. */
 143 static unsigned long default_retry_ms = 2000;
 144 module_param(default_retry_ms, ulong, 0644);
 145 MODULE_PARM_DESC(default_retry_ms,
 146                  "The time (milliseconds) between retry sends");
 147
 148 /* The default timeout for maintenance mode message retries. */
 149 static unsigned long default_maintenance_retry_ms = 3000;
 150 module_param(default_maintenance_retry_ms, ulong, 0644);
 151 MODULE_PARM_DESC(default_maintenance_retry_ms,
 152                  "The time (milliseconds) between retry sends in maintenance mode");
 153
 154 /* The default maximum number of retries */
 155 static unsigned int default_max_retries = 4;
 156 module_param(default_max_retries, uint, 0644);
 157 MODULE_PARM_DESC(default_max_retries,
 158                  "The time (milliseconds) between retry sends in maintenance mode");
 159
 160 /* Call every ~1000 ms. */
 161 #define IPMI_TIMEOUT_TIME       1000
 162
 163 /* How many jiffies does it take to get to the timeout time. */
 164 #define IPMI_TIMEOUT_JIFFIES    ((IPMI_TIMEOUT_TIME * HZ) / 1000)
 165
 166 /*
 167  * Request events from the queue every second (this is the number of
 168  * IPMI_TIMEOUT_TIMES between event requests).  Hopefully, in the
 169  * future, IPMI will add a way to know immediately if an event is in
 170  * the queue and this silliness can go away.
 171  */
 172 #define IPMI_REQUEST_EV_TIME    (1000 / (IPMI_TIMEOUT_TIME))
 173
 174 /* How long should we cache dynamic device IDs? */
 175 #define IPMI_DYN_DEV_ID_EXPIRY  (10 * HZ)
 176
 177 /*
 178  * The main "user" data structure.
 179  */
 180 struct ipmi_user {
 181         struct list_head link;
 182
 183         /*
 184          * Set to NULL when the user is destroyed, a pointer to myself
 185          * so srcu_dereference can be used on it.
 186          */
 187         struct ipmi_user *self;
 188         struct srcu_struct release_barrier;
 189
 190         struct kref refcount;
 191
 192         /* The upper layer that handles receive messages. */
 193         const struct ipmi_user_hndl *handler;
 194         void             *handler_data;
 195
 196         /* The interface this user is bound to. */
 197         struct ipmi_smi *intf;
 198
 199         /* Does this interface receive IPMI events? */
 200         bool gets_events;
 201
 202         /* Free must run in process context for RCU cleanup. */
 203         struct work_struct remove_work;
 204 };
 205
 206 static struct ipmi_user *acquire_ipmi_user(struct ipmi_user *user, int *index)
 207         __acquires(user->release_barrier)
 208 {
 209         struct ipmi_user *ruser;
 210
 211         *index = srcu_read_lock(&user->release_barrier);
 212         ruser = srcu_dereference(user->self, &user->release_barrier);
 213         if (!ruser)
 214                 srcu_read_unlock(&user->release_barrier, *index);
 215         return ruser;
 216 }
 217
 218 static void release_ipmi_user(struct ipmi_user *user, int index)
 219 {
 220         srcu_read_unlock(&user->release_barrier, index);
 221 }
 222
 223 struct cmd_rcvr {
 224         struct list_head link;
 225
 226         struct ipmi_user *user;
 227         unsigned char netfn;
 228         unsigned char cmd;
 229         unsigned int  chans;
 230
 231         /*
 232          * This is used to form a linked lised during mass deletion.
 233          * Since this is in an RCU list, we cannot use the link above
 234          * or change any data until the RCU period completes.  So we
 235          * use this next variable during mass deletion so we can have
 236          * a list and don't have to wait and restart the search on
 237          * every individual deletion of a command.
 238          */
 239         struct cmd_rcvr *next;
 240 };
 241
 242 struct seq_table {
 243         unsigned int         inuse : 1;
 244         unsigned int         broadcast : 1;
 245
 246         unsigned long        timeout;
 247         unsigned long        orig_timeout;
 248         unsigned int         retries_left;
 249
 250         /*
 251          * To verify on an incoming send message response that this is
 252          * the message that the response is for, we keep a sequence id
 253          * and increment it every time we send a message.
 254          */
 255         long                 seqid;
 256
 257         /*
 258          * This is held so we can properly respond to the message on a
 259          * timeout, and it is used to hold the temporary data for
 260          * retransmission, too.
 261          */
 262         struct ipmi_recv_msg *recv_msg;
 263 };
 264
 265 /*
 266  * Store the information in a msgid (long) to allow us to find a
 267  * sequence table entry from the msgid.
 268  */
 269 #define STORE_SEQ_IN_MSGID(seq, seqid) \
 270         ((((seq) & 0x3f) << 26) | ((seqid) & 0x3ffffff))
 271
 272 #define GET_SEQ_FROM_MSGID(msgid, seq, seqid) \
 273         do {                                                            \
 274                 seq = (((msgid) >> 26) & 0x3f);                         \
 275                 seqid = ((msgid) & 0x3ffffff);                          \
 276         } while (0)
 277
 278 #define NEXT_SEQID(seqid) (((seqid) + 1) & 0x3ffffff)
 279
 280 #define IPMI_MAX_CHANNELS       16
 281 struct ipmi_channel {
 282         unsigned char medium;
 283         unsigned char protocol;
 284 };
 285
 286 struct ipmi_channel_set {
 287         struct ipmi_channel c[IPMI_MAX_CHANNELS];
 288 };
 289
 290 struct ipmi_my_addrinfo {
 291         /*
 292          * My slave address.  This is initialized to IPMI_BMC_SLAVE_ADDR,
 293          * but may be changed by the user.
 294          */
 295         unsigned char address;
 296
 297         /*
 298          * My LUN.  This should generally stay the SMS LUN, but just in
 299          * case...
 300          */
 301         unsigned char lun;
 302 };
 303
 304 /*
 305  * Note that the product id, manufacturer id, guid, and device id are
 306  * immutable in this structure, so dyn_mutex is not required for
 307  * accessing those.  If those change on a BMC, a new BMC is allocated.
 308  */
 309 struct bmc_device {
 310         struct platform_device pdev;
 311         struct list_head       intfs; /* Interfaces on this BMC. */
 312         struct ipmi_device_id  id;
 313         struct ipmi_device_id  fetch_id;
 314         int                    dyn_id_set;
 315         unsigned long          dyn_id_expiry;
 316         struct mutex           dyn_mutex; /* Protects id, intfs, & dyn* */
 317         guid_t                 guid;
 318         guid_t                 fetch_guid;
 319         int                    dyn_guid_set;
 320         struct kref            usecount;
 321         struct work_struct     remove_work;
 322         unsigned char          cc; /* completion code */
 323 };
 324 #define to_bmc_device(x) container_of((x), struct bmc_device, pdev.dev)
 325
 326 static int bmc_get_device_id(struct ipmi_smi *intf, struct bmc_device *bmc,
 327                              struct ipmi_device_id *id,
 328                              bool *guid_set, guid_t *guid);
 329
 330 /*
 331  * Various statistics for IPMI, these index stats[] in the ipmi_smi
 332  * structure.
 333  */
 334 enum ipmi_stat_indexes {
 335         /* Commands we got from the user that were invalid. */
 336         IPMI_STAT_sent_invalid_commands = 0,
 337
 338         /* Commands we sent to the MC. */
 339         IPMI_STAT_sent_local_commands,
 340
 341         /* Responses from the MC that were delivered to a user. */
 342         IPMI_STAT_handled_local_responses,
 343
 344         /* Responses from the MC that were not delivered to a user. */
 345         IPMI_STAT_unhandled_local_responses,
 346
 347         /* Commands we sent out to the IPMB bus. */
 348         IPMI_STAT_sent_ipmb_commands,
 349
 350         /* Commands sent on the IPMB that had errors on the SEND CMD */
 351         IPMI_STAT_sent_ipmb_command_errs,
 352
 353         /* Each retransmit increments this count. */
 354         IPMI_STAT_retransmitted_ipmb_commands,
 355
 356         /*
 357          * When a message times out (runs out of retransmits) this is
 358          * incremented.
 359          */
 360         IPMI_STAT_timed_out_ipmb_commands,
 361
 362         /*
 363          * This is like above, but for broadcasts.  Broadcasts are
 364          * *not* included in the above count (they are expected to
 365          * time out).
 366          */
 367         IPMI_STAT_timed_out_ipmb_broadcasts,
 368
 369         /* Responses I have sent to the IPMB bus. */
 370         IPMI_STAT_sent_ipmb_responses,
 371
 372         /* The response was delivered to the user. */
 373         IPMI_STAT_handled_ipmb_responses,
 374
 375         /* The response had invalid data in it. */
 376         IPMI_STAT_invalid_ipmb_responses,
 377
 378         /* The response didn't have anyone waiting for it. */
 379         IPMI_STAT_unhandled_ipmb_responses,
 380
 381         /* Commands we sent out to the IPMB bus. */
 382         IPMI_STAT_sent_lan_commands,
 383
 384         /* Commands sent on the IPMB that had errors on the SEND CMD */
 385         IPMI_STAT_sent_lan_command_errs,
 386
 387         /* Each retransmit increments this count. */
 388         IPMI_STAT_retransmitted_lan_commands,
 389
 390         /*
 391          * When a message times out (runs out of retransmits) this is
 392          * incremented.
 393          */
 394         IPMI_STAT_timed_out_lan_commands,
 395
 396         /* Responses I have sent to the IPMB bus. */
 397         IPMI_STAT_sent_lan_responses,
 398
 399         /* The response was delivered to the user. */
 400         IPMI_STAT_handled_lan_responses,
 401
 402         /* The response had invalid data in it. */
 403         IPMI_STAT_invalid_lan_responses,
 404
 405         /* The response didn't have anyone waiting for it. */
 406         IPMI_STAT_unhandled_lan_responses,
 407
 408         /* The command was delivered to the user. */
 409         IPMI_STAT_handled_commands,
 410
 411         /* The command had invalid data in it. */
 412         IPMI_STAT_invalid_commands,
 413
 414         /* The command didn't have anyone waiting for it. */
 415         IPMI_STAT_unhandled_commands,
 416
 417         /* Invalid data in an event. */
 418         IPMI_STAT_invalid_events,
 419
 420         /* Events that were received with the proper format. */
 421         IPMI_STAT_events,
 422
 423         /* Retransmissions on IPMB that failed. */
 424         IPMI_STAT_dropped_rexmit_ipmb_commands,
 425
 426         /* Retransmissions on LAN that failed. */
 427         IPMI_STAT_dropped_rexmit_lan_commands,
 428
 429         /* This *must* remain last, add new values above this. */
 430         IPMI_NUM_STATS
 431 };
 432
 433
 434 #define IPMI_IPMB_NUM_SEQ       64
 435 struct ipmi_smi {
 436         struct module *owner;
 437
 438         /* What interface number are we? */
 439         int intf_num;
 440
 441         struct kref refcount;
 442
 443         /* Set when the interface is being unregistered. */
 444         bool in_shutdown;
 445
 446         /* Used for a list of interfaces. */
 447         struct list_head link;
 448
 449         /*
 450          * The list of upper layers that are using me.  seq_lock write
 451          * protects this.  Read protection is with srcu.
 452          */
 453         struct list_head users;
 454         struct srcu_struct users_srcu;
 455
 456         /* Used for wake ups at startup. */
 457         wait_queue_head_t waitq;
 458
 459         /*
 460          * Prevents the interface from being unregistered when the
 461          * interface is used by being looked up through the BMC
 462          * structure.
 463          */
 464         struct mutex bmc_reg_mutex;
 465
 466         struct bmc_device tmp_bmc;
 467         struct bmc_device *bmc;
 468         bool bmc_registered;
 469         struct list_head bmc_link;
 470         char *my_dev_name;
 471         bool in_bmc_register;  /* Handle recursive situations.  Yuck. */
 472         struct work_struct bmc_reg_work;
 473
 474         const struct ipmi_smi_handlers *handlers;
 475         void                     *send_info;
 476
 477         /* Driver-model device for the system interface. */
 478         struct device          *si_dev;
 479
 480         /*
 481          * A table of sequence numbers for this interface.  We use the
 482          * sequence numbers for IPMB messages that go out of the
 483          * interface to match them up with their responses.  A routine
 484          * is called periodically to time the items in this list.
 485          */
 486         spinlock_t       seq_lock;
 487         struct seq_table seq_table[IPMI_IPMB_NUM_SEQ];
 488         int curr_seq;
 489
 490         /*
 491          * Messages queued for delivery.  If delivery fails (out of memory
 492          * for instance), They will stay in here to be processed later in a
 493          * periodic timer interrupt.  The tasklet is for handling received
 494          * messages directly from the handler.
 495          */
 496         spinlock_t       waiting_rcv_msgs_lock;
 497         struct list_head waiting_rcv_msgs;
 498         atomic_t         watchdog_pretimeouts_to_deliver;
 499         struct tasklet_struct recv_tasklet;
 500
 501         spinlock_t             xmit_msgs_lock;
 502         struct list_head       xmit_msgs;
 503         struct ipmi_smi_msg    *curr_msg;
 504         struct list_head       hp_xmit_msgs;
 505
 506         /*
 507          * The list of command receivers that are registered for commands
 508          * on this interface.
 509          */
 510         struct mutex     cmd_rcvrs_mutex;
 511         struct list_head cmd_rcvrs;
 512
 513         /*
 514          * Events that were queues because no one was there to receive
 515          * them.
 516          */
 517         spinlock_t       events_lock; /* For dealing with event stuff. */
 518         struct list_head waiting_events;
 519         unsigned int     waiting_events_count; /* How many events in queue? */
 520         char             delivering_events;
 521         char             event_msg_printed;
 522
 523         /* How many users are waiting for events? */
 524         atomic_t         event_waiters;
 525         unsigned int     ticks_to_req_ev;
 526
 527         spinlock_t       watch_lock; /* For dealing with watch stuff below. */
 528
 529         /* How many users are waiting for commands? */
 530         unsigned int     command_waiters;
 531
 532         /* How many users are waiting for watchdogs? */
 533         unsigned int     watchdog_waiters;
 534
 535         /* How many users are waiting for message responses? */
 536         unsigned int     response_waiters;
 537
 538         /*
 539          * Tells what the lower layer has last been asked to watch for,
 540          * messages and/or watchdogs.  Protected by watch_lock.
 541          */
 542         unsigned int     last_watch_mask;
 543
 544         /*
 545          * The event receiver for my BMC, only really used at panic
 546          * shutdown as a place to store this.
 547          */
 548         unsigned char event_receiver;
 549         unsigned char event_receiver_lun;
 550         unsigned char local_sel_device;
 551         unsigned char local_event_generator;
 552
 553         /* For handling of maintenance mode. */
 554         int maintenance_mode;
 555         bool maintenance_mode_enable;
 556         int auto_maintenance_timeout;
 557         spinlock_t maintenance_mode_lock; /* Used in a timer... */
 558
 559         /*
 560          * If we are doing maintenance on something on IPMB, extend
 561          * the timeout time to avoid timeouts writing firmware and
 562          * such.
 563          */
 564         int ipmb_maintenance_mode_timeout;
 565
 566         /*
 567          * A cheap hack, if this is non-null and a message to an
 568          * interface comes in with a NULL user, call this routine with
 569          * it.  Note that the message will still be freed by the
 570          * caller.  This only works on the system interface.
 571          *
 572          * Protected by bmc_reg_mutex.
 573          */
 574         void (*null_user_handler)(struct ipmi_smi *intf,
 575                                   struct ipmi_recv_msg *msg);
 576
 577         /*
 578          * When we are scanning the channels for an SMI, this will
 579          * tell which channel we are scanning.
 580          */
 581         int curr_channel;
 582
 583         /* Channel information */
 584         struct ipmi_channel_set *channel_list;
 585         unsigned int curr_working_cset; /* First index into the following. */
 586         struct ipmi_channel_set wchannels[2];
 587         struct ipmi_my_addrinfo addrinfo[IPMI_MAX_CHANNELS];
 588         bool channels_ready;
 589
 590         atomic_t stats[IPMI_NUM_STATS];
 591
 592         /*
 593          * run_to_completion duplicate of smb_info, smi_info
 594          * and ipmi_serial_info structures. Used to decrease numbers of
 595          * parameters passed by "low" level IPMI code.
 596          */
 597         int run_to_completion;
 598 };
 599 #define to_si_intf_from_dev(device) container_of(device, struct ipmi_smi, dev)
 600
 601 static void __get_guid(struct ipmi_smi *intf);
 602 static void __ipmi_bmc_unregister(struct ipmi_smi *intf);
 603 static int __ipmi_bmc_register(struct ipmi_smi *intf,
 604                                struct ipmi_device_id *id,
 605                                bool guid_set, guid_t *guid, int intf_num);
 606 static int __scan_channels(struct ipmi_smi *intf, struct ipmi_device_id *id);
 607
 608
 609 /**
 610  * The driver model view of the IPMI messaging driver.
 611  */
 612 static struct platform_driver ipmidriver = {
 613         .driver = {
 614                 .name = "ipmi",
 615                 .bus = &platform_bus_type
 616         }
 617 };
 618 /*
 619  * This mutex keeps us from adding the same BMC twice.
 620  */
 621 static DEFINE_MUTEX(ipmidriver_mutex);
 622
 623 static LIST_HEAD(ipmi_interfaces);
 624 static DEFINE_MUTEX(ipmi_interfaces_mutex);
 625 #define ipmi_interfaces_mutex_held() \
 626         lockdep_is_held(&ipmi_interfaces_mutex)
 627 static struct srcu_struct ipmi_interfaces_srcu;
 628
 629 /*
 630  * List of watchers that want to know when smi's are added and deleted.
 631  */
 632 static LIST_HEAD(smi_watchers);
 633 static DEFINE_MUTEX(smi_watchers_mutex);
 634
 635 #define ipmi_inc_stat(intf, stat) \
 636         atomic_inc(&(intf)->stats[IPMI_STAT_ ## stat])
 637 #define ipmi_get_stat(intf, stat) \
 638         ((unsigned int) atomic_read(&(intf)->stats[IPMI_STAT_ ## stat]))
 639
 640 static const char * const addr_src_to_str[] = {
 641         "invalid", "hotmod", "hardcoded", "SPMI", "ACPI", "SMBIOS", "PCI",
 642         "device-tree", "platform"
 643 };
 644
 645 const char *ipmi_addr_src_to_str(enum ipmi_addr_src src)
 646 {
 647         if (src >= SI_LAST)
 648                 src = 0; /* Invalid */
 649         return addr_src_to_str[src];
 650 }
 651 EXPORT_SYMBOL(ipmi_addr_src_to_str);
 652
 653 static int is_lan_addr(struct ipmi_addr *addr)
 654 {
 655         return addr->addr_type == IPMI_LAN_ADDR_TYPE;
 656 }
 657
 658 static int is_ipmb_addr(struct ipmi_addr *addr)
 659 {
 660         return addr->addr_type == IPMI_IPMB_ADDR_TYPE;
 661 }
 662
 663 static int is_ipmb_bcast_addr(struct ipmi_addr *addr)
 664 {
 665         return addr->addr_type == IPMI_IPMB_BROADCAST_ADDR_TYPE;
 666 }
 667
 668 static void free_recv_msg_list(struct list_head *q)
 669 {
 670         struct ipmi_recv_msg *msg, *msg2;
 671
 672         list_for_each_entry_safe(msg, msg2, q, link) {
 673                 list_del(&msg->link);
 674                 ipmi_free_recv_msg(msg);
 675         }
 676 }
 677
 678 static void free_smi_msg_list(struct list_head *q)
 679 {
 680         struct ipmi_smi_msg *msg, *msg2;
 681
 682         list_for_each_entry_safe(msg, msg2, q, link) {
 683                 list_del(&msg->link);
 684                 ipmi_free_smi_msg(msg);
 685         }
 686 }
 687
 688 static void clean_up_interface_data(struct ipmi_smi *intf)
 689 {
 690         int              i;
 691         struct cmd_rcvr  *rcvr, *rcvr2;
 692         struct list_head list;
 693
 694         tasklet_kill(&intf->recv_tasklet);
 695
 696         free_smi_msg_list(&intf->waiting_rcv_msgs);
 697         free_recv_msg_list(&intf->waiting_events);
 698
 699         /*
 700          * Wholesale remove all the entries from the list in the
 701          * interface and wait for RCU to know that none are in use.
 702          */
 703         mutex_lock(&intf->cmd_rcvrs_mutex);
 704         INIT_LIST_HEAD(&list);
 705         list_splice_init_rcu(&intf->cmd_rcvrs, &list, synchronize_rcu);
 706         mutex_unlock(&intf->cmd_rcvrs_mutex);
 707
 708         list_for_each_entry_safe(rcvr, rcvr2, &list, link)
 709                 kfree(rcvr);
 710
 711         for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++) {
 712                 if ((intf->seq_table[i].inuse)
 713                                         && (intf->seq_table[i].recv_msg))
 714                         ipmi_free_recv_msg(intf->seq_table[i].recv_msg);
 715         }
 716 }
 717
 718 static void intf_free(struct kref *ref)
 719 {
 720         struct ipmi_smi *intf = container_of(ref, struct ipmi_smi, refcount);
 721
 722         clean_up_interface_data(intf);
 723         kfree(intf);
 724 }
 725
 726 struct watcher_entry {
 727         int              intf_num;
 728         struct ipmi_smi  *intf;
 729         struct list_head link;
 730 };
 731
 732 int ipmi_smi_watcher_register(struct ipmi_smi_watcher *watcher)
 733 {
 734         struct ipmi_smi *intf;
 735         int index, rv;
 736
 737         /*
 738          * Make sure the driver is actually initialized, this handles
 739          * problems with initialization order.
 740          */
 741         rv = ipmi_init_msghandler();
 742         if (rv)
 743                 return rv;
 744
 745         mutex_lock(&smi_watchers_mutex);
 746
 747         list_add(&watcher->link, &smi_watchers);
 748
 749         index = srcu_read_lock(&ipmi_interfaces_srcu);
 750         list_for_each_entry_rcu(intf, &ipmi_interfaces, link,
 751                         lockdep_is_held(&smi_watchers_mutex)) {
 752                 int intf_num = READ_ONCE(intf->intf_num);
 753
 754                 if (intf_num == -1)
 755                         continue;
 756                 watcher->new_smi(intf_num, intf->si_dev);
 757         }
 758         srcu_read_unlock(&ipmi_interfaces_srcu, index);
 759
 760         mutex_unlock(&smi_watchers_mutex);
 761
 762         return 0;
 763 }
 764 EXPORT_SYMBOL(ipmi_smi_watcher_register);
 765
 766 int ipmi_smi_watcher_unregister(struct ipmi_smi_watcher *watcher)
 767 {
 768         mutex_lock(&smi_watchers_mutex);
 769         list_del(&watcher->link);
 770         mutex_unlock(&smi_watchers_mutex);
 771         return 0;
 772 }
 773 EXPORT_SYMBOL(ipmi_smi_watcher_unregister);
 774
 775 /*
 776  * Must be called with smi_watchers_mutex held.
 777  */
 778 static void
 779 call_smi_watchers(int i, struct device *dev)
 780 {
 781         struct ipmi_smi_watcher *w;
 782
 783         mutex_lock(&smi_watchers_mutex);
 784         list_for_each_entry(w, &smi_watchers, link) {
 785                 if (try_module_get(w->owner)) {
 786                         w->new_smi(i, dev);
 787                         module_put(w->owner);
 788                 }
 789         }
 790         mutex_unlock(&smi_watchers_mutex);
 791 }
 792
 793 static int
 794 ipmi_addr_equal(struct ipmi_addr *addr1, struct ipmi_addr *addr2)
 795 {
 796         if (addr1->addr_type != addr2->addr_type)
 797                 return 0;
 798
 799         if (addr1->channel != addr2->channel)
 800                 return 0;
 801
 802         if (addr1->addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE) {
 803                 struct ipmi_system_interface_addr *smi_addr1
 804                     = (struct ipmi_system_interface_addr *) addr1;
 805                 struct ipmi_system_interface_addr *smi_addr2
 806                     = (struct ipmi_system_interface_addr *) addr2;
 807                 return (smi_addr1->lun == smi_addr2->lun);
 808         }
 809
 810         if (is_ipmb_addr(addr1) || is_ipmb_bcast_addr(addr1)) {
 811                 struct ipmi_ipmb_addr *ipmb_addr1
 812                     = (struct ipmi_ipmb_addr *) addr1;
 813                 struct ipmi_ipmb_addr *ipmb_addr2
 814                     = (struct ipmi_ipmb_addr *) addr2;
 815
 816                 return ((ipmb_addr1->slave_addr == ipmb_addr2->slave_addr)
 817                         && (ipmb_addr1->lun == ipmb_addr2->lun));
 818         }
 819
 820         if (is_lan_addr(addr1)) {
 821                 struct ipmi_lan_addr *lan_addr1
 822                         = (struct ipmi_lan_addr *) addr1;
 823                 struct ipmi_lan_addr *lan_addr2
 824                     = (struct ipmi_lan_addr *) addr2;
 825
 826                 return ((lan_addr1->remote_SWID == lan_addr2->remote_SWID)
 827                         && (lan_addr1->local_SWID == lan_addr2->local_SWID)
 828                         && (lan_addr1->session_handle
 829                             == lan_addr2->session_handle)
 830                         && (lan_addr1->lun == lan_addr2->lun));
 831         }
 832
 833         return 1;
 834 }
 835
 836 int ipmi_validate_addr(struct ipmi_addr *addr, int len)
 837 {
 838         if (len < sizeof(struct ipmi_system_interface_addr))
 839                 return -EINVAL;
 840
 841         if (addr->addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE) {
 842                 if (addr->channel != IPMI_BMC_CHANNEL)
 843                         return -EINVAL;
 844                 return 0;
 845         }
 846
 847         if ((addr->channel == IPMI_BMC_CHANNEL)
 848             || (addr->channel >= IPMI_MAX_CHANNELS)
 849             || (addr->channel < 0))
 850                 return -EINVAL;
 851
 852         if (is_ipmb_addr(addr) || is_ipmb_bcast_addr(addr)) {
 853                 if (len < sizeof(struct ipmi_ipmb_addr))
 854                         return -EINVAL;
 855                 return 0;
 856         }
 857
 858         if (is_lan_addr(addr)) {
 859                 if (len < sizeof(struct ipmi_lan_addr))
 860                         return -EINVAL;
 861                 return 0;
 862         }
 863
 864         return -EINVAL;
 865 }
 866 EXPORT_SYMBOL(ipmi_validate_addr);
 867
 868 unsigned int ipmi_addr_length(int addr_type)
 869 {
 870         if (addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
 871                 return sizeof(struct ipmi_system_interface_addr);
 872
 873         if ((addr_type == IPMI_IPMB_ADDR_TYPE)
 874                         || (addr_type == IPMI_IPMB_BROADCAST_ADDR_TYPE))
 875                 return sizeof(struct ipmi_ipmb_addr);
 876
 877         if (addr_type == IPMI_LAN_ADDR_TYPE)
 878                 return sizeof(struct ipmi_lan_addr);
 879
 880         return 0;
 881 }
 882 EXPORT_SYMBOL(ipmi_addr_length);
 883
 884 static int deliver_response(struct ipmi_smi *intf, struct ipmi_recv_msg *msg)
 885 {
 886         int rv = 0;
 887
 888         if (!msg->user) {
 889                 /* Special handling for NULL users. */
 890                 if (intf->null_user_handler) {
 891                         intf->null_user_handler(intf, msg);
 892                 } else {
 893                         /* No handler, so give up. */
 894                         rv = -EINVAL;
 895                 }
 896                 ipmi_free_recv_msg(msg);
 897         } else if (oops_in_progress) {
 898                 /*
 899                  * If we are running in the panic context, calling the
 900                  * receive handler doesn't much meaning and has a deadlock
 901                  * risk.  At this moment, simply skip it in that case.
 902                  */
 903                 ipmi_free_recv_msg(msg);
 904         } else {
 905                 int index;
 906                 struct ipmi_user *user = acquire_ipmi_user(msg->user, &index);
 907
 908                 if (user) {
 909                         user->handler->ipmi_recv_hndl(msg, user->handler_data);
 910                         release_ipmi_user(user, index);
 911                 } else {
 912                         /* User went away, give up. */
 913                         ipmi_free_recv_msg(msg);
 914                         rv = -EINVAL;
 915                 }
 916         }
 917
 918         return rv;
 919 }
 920
 921 static void deliver_local_response(struct ipmi_smi *intf,
 922                                    struct ipmi_recv_msg *msg)
 923 {
 924         if (deliver_response(intf, msg))
 925                 ipmi_inc_stat(intf, unhandled_local_responses);
 926         else
 927                 ipmi_inc_stat(intf, handled_local_responses);
 928 }
 929
 930 static void deliver_err_response(struct ipmi_smi *intf,
 931                                  struct ipmi_recv_msg *msg, int err)
 932 {
 933         msg->recv_type = IPMI_RESPONSE_RECV_TYPE;
 934         msg->msg_data[0] = err;
 935         msg->msg.netfn |= 1; /* Convert to a response. */
 936         msg->msg.data_len = 1;
 937         msg->msg.data = msg->msg_data;
 938         deliver_local_response(intf, msg);
 939 }
 940
 941 static void smi_add_watch(struct ipmi_smi *intf, unsigned int flags)
 942 {
 943         unsigned long iflags;
 944
 945         if (!intf->handlers->set_need_watch)
 946                 return;
 947
 948         spin_lock_irqsave(&intf->watch_lock, iflags);
 949         if (flags & IPMI_WATCH_MASK_CHECK_MESSAGES)
 950                 intf->response_waiters++;
 951
 952         if (flags & IPMI_WATCH_MASK_CHECK_WATCHDOG)
 953                 intf->watchdog_waiters++;
 954
 955         if (flags & IPMI_WATCH_MASK_CHECK_COMMANDS)
 956                 intf->command_waiters++;
 957
 958         if ((intf->last_watch_mask & flags) != flags) {
 959                 intf->last_watch_mask |= flags;
 960                 intf->handlers->set_need_watch(intf->send_info,
 961                                                intf->last_watch_mask);
 962         }
 963         spin_unlock_irqrestore(&intf->watch_lock, iflags);
 964 }
 965
 966 static void smi_remove_watch(struct ipmi_smi *intf, unsigned int flags)
 967 {
 968         unsigned long iflags;
 969
 970         if (!intf->handlers->set_need_watch)
 971                 return;
 972
 973         spin_lock_irqsave(&intf->watch_lock, iflags);
 974         if (flags & IPMI_WATCH_MASK_CHECK_MESSAGES)
 975                 intf->response_waiters--;
 976
 977         if (flags & IPMI_WATCH_MASK_CHECK_WATCHDOG)
 978                 intf->watchdog_waiters--;
 979
 980         if (flags & IPMI_WATCH_MASK_CHECK_COMMANDS)
 981                 intf->command_waiters--;
 982
 983         flags = 0;
 984         if (intf->response_waiters)
 985                 flags |= IPMI_WATCH_MASK_CHECK_MESSAGES;
 986         if (intf->watchdog_waiters)
 987                 flags |= IPMI_WATCH_MASK_CHECK_WATCHDOG;
 988         if (intf->command_waiters)
 989                 flags |= IPMI_WATCH_MASK_CHECK_COMMANDS;
 990
 991         if (intf->last_watch_mask != flags) {
 992                 intf->last_watch_mask = flags;
 993                 intf->handlers->set_need_watch(intf->send_info,
 994                                                intf->last_watch_mask);
 995         }
 996         spin_unlock_irqrestore(&intf->watch_lock, iflags);
 997 }
 998
 999 /*
1000  * Find the next sequence number not being used and add the given
1001  * message with the given timeout to the sequence table.  This must be
1002  * called with the interface's seq_lock held.
1003  */
1004 static int intf_next_seq(struct ipmi_smi      *intf,
1005                          struct ipmi_recv_msg *recv_msg,
1006                          unsigned long        timeout,
1007                          int                  retries,
1008                          int                  broadcast,
1009                          unsigned char        *seq,
1010                          long                 *seqid)
1011 {
1012         int          rv = 0;
1013         unsigned int i;
1014
1015         if (timeout == 0)
1016                 timeout = default_retry_ms;
1017         if (retries < 0)
1018                 retries = default_max_retries;
1019
1020         for (i = intf->curr_seq; (i+1)%IPMI_IPMB_NUM_SEQ != intf->curr_seq;
1021                                         i = (i+1)%IPMI_IPMB_NUM_SEQ) {
1022                 if (!intf->seq_table[i].inuse)
1023                         break;
1024         }
1025
1026         if (!intf->seq_table[i].inuse) {
1027                 intf->seq_table[i].recv_msg = recv_msg;
1028
1029                 /*
1030                  * Start with the maximum timeout, when the send response
1031                  * comes in we will start the real timer.
1032                  */
1033                 intf->seq_table[i].timeout = MAX_MSG_TIMEOUT;
1034                 intf->seq_table[i].orig_timeout = timeout;
1035                 intf->seq_table[i].retries_left = retries;
1036                 intf->seq_table[i].broadcast = broadcast;
1037                 intf->seq_table[i].inuse = 1;
1038                 intf->seq_table[i].seqid = NEXT_SEQID(intf->seq_table[i].seqid);
1039                 *seq = i;
1040                 *seqid = intf->seq_table[i].seqid;
1041                 intf->curr_seq = (i+1)%IPMI_IPMB_NUM_SEQ;
1042                 smi_add_watch(intf, IPMI_WATCH_MASK_CHECK_MESSAGES);
1043                 need_waiter(intf);
1044         } else {
1045                 rv = -EAGAIN;
1046         }
1047
1048         return rv;
1049 }
1050
1051 /*
1052  * Return the receive message for the given sequence number and
1053  * release the sequence number so it can be reused.  Some other data
1054  * is passed in to be sure the message matches up correctly (to help
1055  * guard against message coming in after their timeout and the
1056  * sequence number being reused).
1057  */
1058 static int intf_find_seq(struct ipmi_smi      *intf,
1059                          unsigned char        seq,
1060                          short                channel,
1061                          unsigned char        cmd,
1062                          unsigned char        netfn,
1063                          struct ipmi_addr     *addr,
1064                          struct ipmi_recv_msg **recv_msg)
1065 {
1066         int           rv = -ENODEV;
1067         unsigned long flags;
1068
1069         if (seq >= IPMI_IPMB_NUM_SEQ)
1070                 return -EINVAL;
1071
1072         spin_lock_irqsave(&intf->seq_lock, flags);
1073         if (intf->seq_table[seq].inuse) {
1074                 struct ipmi_recv_msg *msg = intf->seq_table[seq].recv_msg;
1075
1076                 if ((msg->addr.channel == channel) && (msg->msg.cmd == cmd)
1077                                 && (msg->msg.netfn == netfn)
1078                                 && (ipmi_addr_equal(addr, &msg->addr))) {
1079                         *recv_msg = msg;
1080                         intf->seq_table[seq].inuse = 0;
1081                         smi_remove_watch(intf, IPMI_WATCH_MASK_CHECK_MESSAGES);
1082                         rv = 0;
1083                 }
1084         }
1085         spin_unlock_irqrestore(&intf->seq_lock, flags);
1086
1087         return rv;
1088 }
1089
1090
1091 /* Start the timer for a specific sequence table entry. */
1092 static int intf_start_seq_timer(struct ipmi_smi *intf,
1093                                 long       msgid)
1094 {
1095         int           rv = -ENODEV;
1096         unsigned long flags;
1097         unsigned char seq;
1098         unsigned long seqid;
1099
1100
1101         GET_SEQ_FROM_MSGID(msgid, seq, seqid);
1102
1103         spin_lock_irqsave(&intf->seq_lock, flags);
1104         /*
1105          * We do this verification because the user can be deleted
1106          * while a message is outstanding.
1107          */
1108         if ((intf->seq_table[seq].inuse)
1109                                 && (intf->seq_table[seq].seqid == seqid)) {
1110                 struct seq_table *ent = &intf->seq_table[seq];
1111                 ent->timeout = ent->orig_timeout;
1112                 rv = 0;
1113         }
1114         spin_unlock_irqrestore(&intf->seq_lock, flags);
1115
1116         return rv;
1117 }
1118
1119 /* Got an error for the send message for a specific sequence number. */
1120 static int intf_err_seq(struct ipmi_smi *intf,
1121                         long         msgid,
1122                         unsigned int err)
1123 {
1124         int                  rv = -ENODEV;
1125         unsigned long        flags;
1126         unsigned char        seq;
1127         unsigned long        seqid;
1128         struct ipmi_recv_msg *msg = NULL;
1129
1130
1131         GET_SEQ_FROM_MSGID(msgid, seq, seqid);
1132
1133         spin_lock_irqsave(&intf->seq_lock, flags);
1134         /*
1135          * We do this verification because the user can be deleted
1136          * while a message is outstanding.
1137          */
1138         if ((intf->seq_table[seq].inuse)
1139                                 && (intf->seq_table[seq].seqid == seqid)) {
1140                 struct seq_table *ent = &intf->seq_table[seq];
1141
1142                 ent->inuse = 0;
1143                 smi_remove_watch(intf, IPMI_WATCH_MASK_CHECK_MESSAGES);
1144                 msg = ent->recv_msg;
1145                 rv = 0;
1146         }
1147         spin_unlock_irqrestore(&intf->seq_lock, flags);
1148
1149         if (msg)
1150                 deliver_err_response(intf, msg, err);
1151
1152         return rv;
1153 }
1154
1155 static void free_user_work(struct work_struct *work)
1156 {
1157         struct ipmi_user *user = container_of(work, struct ipmi_user,
1158                                               remove_work);
1159
1160         cleanup_srcu_struct(&user->release_barrier);
1161         vfree(user);
1162 }
1163
1164 int ipmi_create_user(unsigned int          if_num,
1165                      const struct ipmi_user_hndl *handler,
1166                      void                  *handler_data,
1167                      struct ipmi_user      **user)
1168 {
1169         unsigned long flags;
1170         struct ipmi_user *new_user;
1171         int           rv, index;
1172         struct ipmi_smi *intf;
1173
1174         /*
1175          * There is no module usecount here, because it's not
1176          * required.  Since this can only be used by and called from
1177          * other modules, they will implicitly use this module, and
1178          * thus this can't be removed unless the other modules are
1179          * removed.
1180          */
1181
1182         if (handler == NULL)
1183                 return -EINVAL;
1184
1185         /*
1186          * Make sure the driver is actually initialized, this handles
1187          * problems with initialization order.
1188          */
1189         rv = ipmi_init_msghandler();
1190         if (rv)
1191                 return rv;
1192
1193         new_user = vzalloc(sizeof(*new_user));
1194         if (!new_user)
1195                 return -ENOMEM;
1196
1197         index = srcu_read_lock(&ipmi_interfaces_srcu);
1198         list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
1199                 if (intf->intf_num == if_num)
1200                         goto found;
1201         }
1202         /* Not found, return an error */
1203         rv = -EINVAL;
1204         goto out_kfree;
1205
1206  found:
1207         INIT_WORK(&new_user->remove_work, free_user_work);
1208
1209         rv = init_srcu_struct(&new_user->release_barrier);
1210         if (rv)
1211                 goto out_kfree;
1212
1213         if (!try_module_get(intf->owner)) {
1214                 rv = -ENODEV;
1215                 goto out_kfree;
1216         }
1217
1218         /* Note that each existing user holds a refcount to the interface. */
1219         kref_get(&intf->refcount);
1220
1221         kref_init(&new_user->refcount);
1222         new_user->handler = handler;
1223         new_user->handler_data = handler_data;
1224         new_user->intf = intf;
1225         new_user->gets_events = false;
1226
1227         rcu_assign_pointer(new_user->self, new_user);
1228         spin_lock_irqsave(&intf->seq_lock, flags);
1229         list_add_rcu(&new_user->link, &intf->users);
1230         spin_unlock_irqrestore(&intf->seq_lock, flags);
1231         if (handler->ipmi_watchdog_pretimeout)
1232                 /* User wants pretimeouts, so make sure to watch for them. */
1233                 smi_add_watch(intf, IPMI_WATCH_MASK_CHECK_WATCHDOG);
1234         srcu_read_unlock(&ipmi_interfaces_srcu, index);
1235         *user = new_user;
1236         return 0;
1237
1238 out_kfree:
1239         srcu_read_unlock(&ipmi_interfaces_srcu, index);
1240         vfree(new_user);
1241         return rv;
1242 }
1243 EXPORT_SYMBOL(ipmi_create_user);
1244
1245 int ipmi_get_smi_info(int if_num, struct ipmi_smi_info *data)
1246 {
1247         int rv, index;
1248         struct ipmi_smi *intf;
1249
1250         index = srcu_read_lock(&ipmi_interfaces_srcu);
1251         list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
1252                 if (intf->intf_num == if_num)
1253                         goto found;
1254         }
1255         srcu_read_unlock(&ipmi_interfaces_srcu, index);
1256
1257         /* Not found, return an error */
1258         return -EINVAL;
1259
1260 found:
1261         if (!intf->handlers->get_smi_info)
1262                 rv = -ENOTTY;
1263         else
1264                 rv = intf->handlers->get_smi_info(intf->send_info, data);
1265         srcu_read_unlock(&ipmi_interfaces_srcu, index);
1266
1267         return rv;
1268 }
1269 EXPORT_SYMBOL(ipmi_get_smi_info);
1270
1271 static void free_user(struct kref *ref)
1272 {
1273         struct ipmi_user *user = container_of(ref, struct ipmi_user, refcount);
1274
1275         /* SRCU cleanup must happen in task context. */
1276         schedule_work(&user->remove_work);
1277 }
1278
1279 static void _ipmi_destroy_user(struct ipmi_user *user)
1280 {
1281         struct ipmi_smi  *intf = user->intf;
1282         int              i;
1283         unsigned long    flags;
1284         struct cmd_rcvr  *rcvr;
1285         struct cmd_rcvr  *rcvrs = NULL;
1286
1287         if (!acquire_ipmi_user(user, &i)) {
1288                 /*
1289                  * The user has already been cleaned up, just make sure
1290                  * nothing is using it and return.
1291                  */
1292                 synchronize_srcu(&user->release_barrier);
1293                 return;
1294         }
1295
1296         rcu_assign_pointer(user->self, NULL);
1297         release_ipmi_user(user, i);
1298
1299         synchronize_srcu(&user->release_barrier);
1300
1301         if (user->handler->shutdown)
1302                 user->handler->shutdown(user->handler_data);
1303
1304         if (user->handler->ipmi_watchdog_pretimeout)
1305                 smi_remove_watch(intf, IPMI_WATCH_MASK_CHECK_WATCHDOG);
1306
1307         if (user->gets_events)
1308                 atomic_dec(&intf->event_waiters);
1309
1310         /* Remove the user from the interface's sequence table. */
1311         spin_lock_irqsave(&intf->seq_lock, flags);
1312         list_del_rcu(&user->link);
1313
1314         for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++) {
1315                 if (intf->seq_table[i].inuse
1316                     && (intf->seq_table[i].recv_msg->user == user)) {
1317                         intf->seq_table[i].inuse = 0;
1318                         smi_remove_watch(intf, IPMI_WATCH_MASK_CHECK_MESSAGES);
1319                         ipmi_free_recv_msg(intf->seq_table[i].recv_msg);
1320                 }
1321         }
1322         spin_unlock_irqrestore(&intf->seq_lock, flags);
1323
1324         /*
1325          * Remove the user from the command receiver's table.  First
1326          * we build a list of everything (not using the standard link,
1327          * since other things may be using it till we do
1328          * synchronize_srcu()) then free everything in that list.
1329          */
1330         mutex_lock(&intf->cmd_rcvrs_mutex);
1331         list_for_each_entry_rcu(rcvr, &intf->cmd_rcvrs, link,
1332                                 lockdep_is_held(&intf->cmd_rcvrs_mutex)) {
1333                 if (rcvr->user == user) {
1334                         list_del_rcu(&rcvr->link);
1335                         rcvr->next = rcvrs;
1336                         rcvrs = rcvr;
1337                 }
1338         }
1339         mutex_unlock(&intf->cmd_rcvrs_mutex);
1340         synchronize_rcu();
1341         while (rcvrs) {
1342                 rcvr = rcvrs;
1343                 rcvrs = rcvr->next;
1344                 kfree(rcvr);
1345         }
1346
1347         kref_put(&intf->refcount, intf_free);
1348         module_put(intf->owner);
1349 }
1350
1351 int ipmi_destroy_user(struct ipmi_user *user)
1352 {
1353         _ipmi_destroy_user(user);
1354
1355         kref_put(&user->refcount, free_user);
1356
1357         return 0;
1358 }
1359 EXPORT_SYMBOL(ipmi_destroy_user);
1360
1361 int ipmi_get_version(struct ipmi_user *user,
1362                      unsigned char *major,
1363                      unsigned char *minor)
1364 {
1365         struct ipmi_device_id id;
1366         int rv, index;
1367
1368         user = acquire_ipmi_user(user, &index);
1369         if (!user)
1370                 return -ENODEV;
1371
1372         rv = bmc_get_device_id(user->intf, NULL, &id, NULL, NULL);
1373         if (!rv) {
1374                 *major = ipmi_version_major(&id);
1375                 *minor = ipmi_version_minor(&id);
1376         }
1377         release_ipmi_user(user, index);
1378
1379         return rv;
1380 }
1381 EXPORT_SYMBOL(ipmi_get_version);
1382
1383 int ipmi_set_my_address(struct ipmi_user *user,
1384                         unsigned int  channel,
1385                         unsigned char address)
1386 {
1387         int index, rv = 0;
1388
1389         user = acquire_ipmi_user(user, &index);
1390         if (!user)
1391                 return -ENODEV;
1392
1393         if (channel >= IPMI_MAX_CHANNELS) {
1394                 rv = -EINVAL;
1395         } else {
1396                 channel = array_index_nospec(channel, IPMI_MAX_CHANNELS);
1397                 user->intf->addrinfo[channel].address = address;
1398         }
1399         release_ipmi_user(user, index);
1400
1401         return rv;
1402 }
1403 EXPORT_SYMBOL(ipmi_set_my_address);
1404
1405 int ipmi_get_my_address(struct ipmi_user *user,
1406                         unsigned int  channel,
1407                         unsigned char *address)
1408 {
1409         int index, rv = 0;
1410
1411         user = acquire_ipmi_user(user, &index);
1412         if (!user)
1413                 return -ENODEV;
1414
1415         if (channel >= IPMI_MAX_CHANNELS) {
1416                 rv = -EINVAL;
1417         } else {
1418                 channel = array_index_nospec(channel, IPMI_MAX_CHANNELS);
1419                 *address = user->intf->addrinfo[channel].address;
1420         }
1421         release_ipmi_user(user, index);
1422
1423         return rv;
1424 }
1425 EXPORT_SYMBOL(ipmi_get_my_address);
1426
1427 int ipmi_set_my_LUN(struct ipmi_user *user,
1428                     unsigned int  channel,
1429                     unsigned char LUN)
1430 {
1431         int index, rv = 0;
1432
1433         user = acquire_ipmi_user(user, &index);
1434         if (!user)
1435                 return -ENODEV;
1436
1437         if (channel >= IPMI_MAX_CHANNELS) {
1438                 rv = -EINVAL;
1439         } else {
1440                 channel = array_index_nospec(channel, IPMI_MAX_CHANNELS);
1441                 user->intf->addrinfo[channel].lun = LUN & 0x3;
1442         }
1443         release_ipmi_user(user, index);
1444
1445         return rv;
1446 }
1447 EXPORT_SYMBOL(ipmi_set_my_LUN);
1448
1449 int ipmi_get_my_LUN(struct ipmi_user *user,
1450                     unsigned int  channel,
1451                     unsigned char *address)
1452 {
1453         int index, rv = 0;
1454
1455         user = acquire_ipmi_user(user, &index);
1456         if (!user)
1457                 return -ENODEV;
1458
1459         if (channel >= IPMI_MAX_CHANNELS) {
1460                 rv = -EINVAL;
1461         } else {
1462                 channel = array_index_nospec(channel, IPMI_MAX_CHANNELS);
1463                 *address = user->intf->addrinfo[channel].lun;
1464         }
1465         release_ipmi_user(user, index);
1466
1467         return rv;
1468 }
1469 EXPORT_SYMBOL(ipmi_get_my_LUN);
1470
1471 int ipmi_get_maintenance_mode(struct ipmi_user *user)
1472 {
1473         int mode, index;
1474         unsigned long flags;
1475
1476         user = acquire_ipmi_user(user, &index);
1477         if (!user)
1478                 return -ENODEV;
1479
1480         spin_lock_irqsave(&user->intf->maintenance_mode_lock, flags);
1481         mode = user->intf->maintenance_mode;
1482         spin_unlock_irqrestore(&user->intf->maintenance_mode_lock, flags);
1483         release_ipmi_user(user, index);
1484
1485         return mode;
1486 }
1487 EXPORT_SYMBOL(ipmi_get_maintenance_mode);
1488
1489 static void maintenance_mode_update(struct ipmi_smi *intf)
1490 {
1491         if (intf->handlers->set_maintenance_mode)
1492                 intf->handlers->set_maintenance_mode(
1493                         intf->send_info, intf->maintenance_mode_enable);
1494 }
1495
1496 int ipmi_set_maintenance_mode(struct ipmi_user *user, int mode)
1497 {
1498         int rv = 0, index;
1499         unsigned long flags;
1500         struct ipmi_smi *intf = user->intf;
1501
1502         user = acquire_ipmi_user(user, &index);
1503         if (!user)
1504                 return -ENODEV;
1505
1506         spin_lock_irqsave(&intf->maintenance_mode_lock, flags);
1507         if (intf->maintenance_mode != mode) {
1508                 switch (mode) {
1509                 case IPMI_MAINTENANCE_MODE_AUTO:
1510                         intf->maintenance_mode_enable
1511                                 = (intf->auto_maintenance_timeout > 0);
1512                         break;
1513
1514                 case IPMI_MAINTENANCE_MODE_OFF:
1515                         intf->maintenance_mode_enable = false;
1516                         break;
1517
1518                 case IPMI_MAINTENANCE_MODE_ON:
1519                         intf->maintenance_mode_enable = true;
1520                         break;
1521
1522                 default:
1523                         rv = -EINVAL;
1524                         goto out_unlock;
1525                 }
1526                 intf->maintenance_mode = mode;
1527
1528                 maintenance_mode_update(intf);
1529         }
1530  out_unlock:
1531         spin_unlock_irqrestore(&intf->maintenance_mode_lock, flags);
1532         release_ipmi_user(user, index);
1533
1534         return rv;
1535 }
1536 EXPORT_SYMBOL(ipmi_set_maintenance_mode);
1537
1538 int ipmi_set_gets_events(struct ipmi_user *user, bool val)
1539 {
1540         unsigned long        flags;
1541         struct ipmi_smi      *intf = user->intf;
1542         struct ipmi_recv_msg *msg, *msg2;
1543         struct list_head     msgs;
1544         int index;
1545
1546         user = acquire_ipmi_user(user, &index);
1547         if (!user)
1548                 return -ENODEV;
1549
1550         INIT_LIST_HEAD(&msgs);
1551
1552         spin_lock_irqsave(&intf->events_lock, flags);
1553         if (user->gets_events == val)
1554                 goto out;
1555
1556         user->gets_events = val;
1557
1558         if (val) {
1559                 if (atomic_inc_return(&intf->event_waiters) == 1)
1560                         need_waiter(intf);
1561         } else {
1562                 atomic_dec(&intf->event_waiters);
1563         }
1564
1565         if (intf->delivering_events)
1566                 /*
1567                  * Another thread is delivering events for this, so
1568                  * let it handle any new events.
1569                  */
1570                 goto out;
1571
1572         /* Deliver any queued events. */
1573         while (user->gets_events && !list_empty(&intf->waiting_events)) {
1574                 list_for_each_entry_safe(msg, msg2, &intf->waiting_events, link)
1575                         list_move_tail(&msg->link, &msgs);
1576                 intf->waiting_events_count = 0;
1577                 if (intf->event_msg_printed) {
1578                         dev_warn(intf->si_dev, "Event queue no longer full\n");
1579                         intf->event_msg_printed = 0;
1580                 }
1581
1582                 intf->delivering_events = 1;
1583                 spin_unlock_irqrestore(&intf->events_lock, flags);
1584
1585                 list_for_each_entry_safe(msg, msg2, &msgs, link) {
1586                         msg->user = user;
1587                         kref_get(&user->refcount);
1588                         deliver_local_response(intf, msg);
1589                 }
1590
1591                 spin_lock_irqsave(&intf->events_lock, flags);
1592                 intf->delivering_events = 0;
1593         }
1594
1595  out:
1596         spin_unlock_irqrestore(&intf->events_lock, flags);
1597         release_ipmi_user(user, index);
1598
1599         return 0;
1600 }
1601 EXPORT_SYMBOL(ipmi_set_gets_events);
1602
1603 static struct cmd_rcvr *find_cmd_rcvr(struct ipmi_smi *intf,
1604                                       unsigned char netfn,
1605                                       unsigned char cmd,
1606                                       unsigned char chan)
1607 {
1608         struct cmd_rcvr *rcvr;
1609
1610         list_for_each_entry_rcu(rcvr, &intf->cmd_rcvrs, link,
1611                                 lockdep_is_held(&intf->cmd_rcvrs_mutex)) {
1612                 if ((rcvr->netfn == netfn) && (rcvr->cmd == cmd)
1613                                         && (rcvr->chans & (1 << chan)))
1614                         return rcvr;
1615         }
1616         return NULL;
1617 }
1618
1619 static int is_cmd_rcvr_exclusive(struct ipmi_smi *intf,
1620                                  unsigned char netfn,
1621                                  unsigned char cmd,
1622                                  unsigned int  chans)
1623 {
1624         struct cmd_rcvr *rcvr;
1625
1626         list_for_each_entry_rcu(rcvr, &intf->cmd_rcvrs, link,
1627                                 lockdep_is_held(&intf->cmd_rcvrs_mutex)) {
1628                 if ((rcvr->netfn == netfn) && (rcvr->cmd == cmd)
1629                                         && (rcvr->chans & chans))
1630                         return 0;
1631         }
1632         return 1;
1633 }
1634
1635 int ipmi_register_for_cmd(struct ipmi_user *user,
1636                           unsigned char netfn,
1637                           unsigned char cmd,
1638                           unsigned int  chans)
1639 {
1640         struct ipmi_smi *intf = user->intf;
1641         struct cmd_rcvr *rcvr;
1642         int rv = 0, index;
1643
1644         user = acquire_ipmi_user(user, &index);
1645         if (!user)
1646                 return -ENODEV;
1647
1648         rcvr = kmalloc(sizeof(*rcvr), GFP_KERNEL);
1649         if (!rcvr) {
1650                 rv = -ENOMEM;
1651                 goto out_release;
1652         }
1653         rcvr->cmd = cmd;
1654         rcvr->netfn = netfn;
1655         rcvr->chans = chans;
1656         rcvr->user = user;
1657
1658         mutex_lock(&intf->cmd_rcvrs_mutex);
1659         /* Make sure the command/netfn is not already registered. */
1660         if (!is_cmd_rcvr_exclusive(intf, netfn, cmd, chans)) {
1661                 rv = -EBUSY;
1662                 goto out_unlock;
1663         }
1664
1665         smi_add_watch(intf, IPMI_WATCH_MASK_CHECK_COMMANDS);
1666
1667         list_add_rcu(&rcvr->link, &intf->cmd_rcvrs);
1668
1669 out_unlock:
1670         mutex_unlock(&intf->cmd_rcvrs_mutex);
1671         if (rv)
1672                 kfree(rcvr);
1673 out_release:
1674         release_ipmi_user(user, index);
1675
1676         return rv;
1677 }
1678 EXPORT_SYMBOL(ipmi_register_for_cmd);
1679
1680 int ipmi_unregister_for_cmd(struct ipmi_user *user,
1681                             unsigned char netfn,
1682                             unsigned char cmd,
1683                             unsigned int  chans)
1684 {
1685         struct ipmi_smi *intf = user->intf;
1686         struct cmd_rcvr *rcvr;
1687         struct cmd_rcvr *rcvrs = NULL;
1688         int i, rv = -ENOENT, index;
1689
1690         user = acquire_ipmi_user(user, &index);
1691         if (!user)
1692                 return -ENODEV;
1693
1694         mutex_lock(&intf->cmd_rcvrs_mutex);
1695         for (i = 0; i < IPMI_NUM_CHANNELS; i++) {
1696                 if (((1 << i) & chans) == 0)
1697                         continue;
1698                 rcvr = find_cmd_rcvr(intf, netfn, cmd, i);
1699                 if (rcvr == NULL)
1700                         continue;
1701                 if (rcvr->user == user) {
1702                         rv = 0;
1703                         rcvr->chans &= ~chans;
1704                         if (rcvr->chans == 0) {
1705                                 list_del_rcu(&rcvr->link);
1706                                 rcvr->next = rcvrs;
1707                                 rcvrs = rcvr;
1708                         }
1709                 }
1710         }
1711         mutex_unlock(&intf->cmd_rcvrs_mutex);
1712         synchronize_rcu();
1713         release_ipmi_user(user, index);
1714         while (rcvrs) {
1715                 smi_remove_watch(intf, IPMI_WATCH_MASK_CHECK_COMMANDS);
1716                 rcvr = rcvrs;
1717                 rcvrs = rcvr->next;
1718                 kfree(rcvr);
1719         }
1720
1721         return rv;
1722 }
1723 EXPORT_SYMBOL(ipmi_unregister_for_cmd);
1724
1725 static unsigned char
1726 ipmb_checksum(unsigned char *data, int size)
1727 {
1728         unsigned char csum = 0;
1729
1730         for (; size > 0; size--, data++)
1731                 csum += *data;
1732
1733         return -csum;
1734 }
1735
1736 static inline void format_ipmb_msg(struct ipmi_smi_msg   *smi_msg,
1737                                    struct kernel_ipmi_msg *msg,
1738                                    struct ipmi_ipmb_addr *ipmb_addr,
1739                                    long                  msgid,
1740                                    unsigned char         ipmb_seq,
1741                                    int                   broadcast,
1742                                    unsigned char         source_address,
1743                                    unsigned char         source_lun)
1744 {
1745         int i = broadcast;
1746
1747         /* Format the IPMB header data. */
1748         smi_msg->data[0] = (IPMI_NETFN_APP_REQUEST << 2);
1749         smi_msg->data[1] = IPMI_SEND_MSG_CMD;
1750         smi_msg->data[2] = ipmb_addr->channel;
1751         if (broadcast)
1752                 smi_msg->data[3] = 0;
1753         smi_msg->data[i+3] = ipmb_addr->slave_addr;
1754         smi_msg->data[i+4] = (msg->netfn << 2) | (ipmb_addr->lun & 0x3);
1755         smi_msg->data[i+5] = ipmb_checksum(&smi_msg->data[i + 3], 2);
1756         smi_msg->data[i+6] = source_address;
1757         smi_msg->data[i+7] = (ipmb_seq << 2) | source_lun;
1758         smi_msg->data[i+8] = msg->cmd;
1759
1760         /* Now tack on the data to the message. */
1761         if (msg->data_len > 0)
1762                 memcpy(&smi_msg->data[i + 9], msg->data, msg->data_len);
1763         smi_msg->data_size = msg->data_len + 9;
1764
1765         /* Now calculate the checksum and tack it on. */
1766         smi_msg->data[i+smi_msg->data_size]
1767                 = ipmb_checksum(&smi_msg->data[i + 6], smi_msg->data_size - 6);
1768
1769         /*
1770          * Add on the checksum size and the offset from the
1771          * broadcast.
1772          */
1773         smi_msg->data_size += 1 + i;
1774
1775         smi_msg->msgid = msgid;
1776 }
1777
1778 static inline void format_lan_msg(struct ipmi_smi_msg   *smi_msg,
1779                                   struct kernel_ipmi_msg *msg,
1780                                   struct ipmi_lan_addr  *lan_addr,
1781                                   long                  msgid,
1782                                   unsigned char         ipmb_seq,
1783                                   unsigned char         source_lun)
1784 {
1785         /* Format the IPMB header data. */
1786         smi_msg->data[0] = (IPMI_NETFN_APP_REQUEST << 2);
1787         smi_msg->data[1] = IPMI_SEND_MSG_CMD;
1788         smi_msg->data[2] = lan_addr->channel;
1789         smi_msg->data[3] = lan_addr->session_handle;
1790         smi_msg->data[4] = lan_addr->remote_SWID;
1791         smi_msg->data[5] = (msg->netfn << 2) | (lan_addr->lun & 0x3);
1792         smi_msg->data[6] = ipmb_checksum(&smi_msg->data[4], 2);
1793         smi_msg->data[7] = lan_addr->local_SWID;
1794         smi_msg->data[8] = (ipmb_seq << 2) | source_lun;
1795         smi_msg->data[9] = msg->cmd;
1796
1797         /* Now tack on the data to the message. */
1798         if (msg->data_len > 0)
1799                 memcpy(&smi_msg->data[10], msg->data, msg->data_len);
1800         smi_msg->data_size = msg->data_len + 10;
1801
1802         /* Now calculate the checksum and tack it on. */
1803         smi_msg->data[smi_msg->data_size]
1804                 = ipmb_checksum(&smi_msg->data[7], smi_msg->data_size - 7);
1805
1806         /*
1807          * Add on the checksum size and the offset from the
1808          * broadcast.
1809          */
1810         smi_msg->data_size += 1;
1811
1812         smi_msg->msgid = msgid;
1813 }
1814
1815 static struct ipmi_smi_msg *smi_add_send_msg(struct ipmi_smi *intf,
1816                                              struct ipmi_smi_msg *smi_msg,
1817                                              int priority)
1818 {
1819         if (intf->curr_msg) {
1820                 if (priority > 0)
1821                         list_add_tail(&smi_msg->link, &intf->hp_xmit_msgs);
1822                 else
1823                         list_add_tail(&smi_msg->link, &intf->xmit_msgs);
1824                 smi_msg = NULL;
1825         } else {
1826                 intf->curr_msg = smi_msg;
1827         }
1828
1829         return smi_msg;
1830 }
1831
1832 static void smi_send(struct ipmi_smi *intf,
1833                      const struct ipmi_smi_handlers *handlers,
1834                      struct ipmi_smi_msg *smi_msg, int priority)
1835 {
1836         int run_to_completion = intf->run_to_completion;
1837         unsigned long flags = 0;
1838
1839         if (!run_to_completion)
1840                 spin_lock_irqsave(&intf->xmit_msgs_lock, flags);
1841         smi_msg = smi_add_send_msg(intf, smi_msg, priority);
1842
1843         if (!run_to_completion)
1844                 spin_unlock_irqrestore(&intf->xmit_msgs_lock, flags);
1845
1846         if (smi_msg)
1847                 handlers->sender(intf->send_info, smi_msg);
1848 }
1849
1850 static bool is_maintenance_mode_cmd(struct kernel_ipmi_msg *msg)
1851 {
1852         return (((msg->netfn == IPMI_NETFN_APP_REQUEST)
1853                  && ((msg->cmd == IPMI_COLD_RESET_CMD)
1854                      || (msg->cmd == IPMI_WARM_RESET_CMD)))
1855                 || (msg->netfn == IPMI_NETFN_FIRMWARE_REQUEST));
1856 }
1857
1858 static int i_ipmi_req_sysintf(struct ipmi_smi        *intf,
1859                               struct ipmi_addr       *addr,
1860                               long                   msgid,
1861                               struct kernel_ipmi_msg *msg,
1862                               struct ipmi_smi_msg    *smi_msg,
1863                               struct ipmi_recv_msg   *recv_msg,
1864                               int                    retries,
1865                               unsigned int           retry_time_ms)
1866 {
1867         struct ipmi_system_interface_addr *smi_addr;
1868
1869         if (msg->netfn & 1)
1870                 /* Responses are not allowed to the SMI. */
1871                 return -EINVAL;
1872
1873         smi_addr = (struct ipmi_system_interface_addr *) addr;
1874         if (smi_addr->lun > 3) {
1875                 ipmi_inc_stat(intf, sent_invalid_commands);
1876                 return -EINVAL;
1877         }
1878
1879         memcpy(&recv_msg->addr, smi_addr, sizeof(*smi_addr));
1880
1881         if ((msg->netfn == IPMI_NETFN_APP_REQUEST)
1882             && ((msg->cmd == IPMI_SEND_MSG_CMD)
1883                 || (msg->cmd == IPMI_GET_MSG_CMD)
1884                 || (msg->cmd == IPMI_READ_EVENT_MSG_BUFFER_CMD))) {
1885                 /*
1886                  * We don't let the user do these, since we manage
1887                  * the sequence numbers.
1888                  */
1889                 ipmi_inc_stat(intf, sent_invalid_commands);
1890                 return -EINVAL;
1891         }
1892
1893         if (is_maintenance_mode_cmd(msg)) {
1894                 unsigned long flags;
1895
1896                 spin_lock_irqsave(&intf->maintenance_mode_lock, flags);
1897                 intf->auto_maintenance_timeout
1898                         = maintenance_mode_timeout_ms;
1899                 if (!intf->maintenance_mode
1900                     && !intf->maintenance_mode_enable) {
1901                         intf->maintenance_mode_enable = true;
1902                         maintenance_mode_update(intf);
1903                 }
1904                 spin_unlock_irqrestore(&intf->maintenance_mode_lock,
1905                                        flags);
1906         }
1907
1908         if (msg->data_len + 2 > IPMI_MAX_MSG_LENGTH) {
1909                 ipmi_inc_stat(intf, sent_invalid_commands);
1910                 return -EMSGSIZE;
1911         }
1912
1913         smi_msg->data[0] = (msg->netfn << 2) | (smi_addr->lun & 0x3);
1914         smi_msg->data[1] = msg->cmd;
1915         smi_msg->msgid = msgid;
1916         smi_msg->user_data = recv_msg;
1917         if (msg->data_len > 0)
1918                 memcpy(&smi_msg->data[2], msg->data, msg->data_len);
1919         smi_msg->data_size = msg->data_len + 2;
1920         ipmi_inc_stat(intf, sent_local_commands);
1921
1922         return 0;
1923 }
1924
1925 static int i_ipmi_req_ipmb(struct ipmi_smi        *intf,
1926                            struct ipmi_addr       *addr,
1927                            long                   msgid,
1928                            struct kernel_ipmi_msg *msg,
1929                            struct ipmi_smi_msg    *smi_msg,
1930                            struct ipmi_recv_msg   *recv_msg,
1931                            unsigned char          source_address,
1932                            unsigned char          source_lun,
1933                            int                    retries,
1934                            unsigned int           retry_time_ms)
1935 {
1936         struct ipmi_ipmb_addr *ipmb_addr;
1937         unsigned char ipmb_seq;
1938         long seqid;
1939         int broadcast = 0;
1940         struct ipmi_channel *chans;
1941         int rv = 0;
1942
1943         if (addr->channel >= IPMI_MAX_CHANNELS) {
1944                 ipmi_inc_stat(intf, sent_invalid_commands);
1945                 return -EINVAL;
1946         }
1947
1948         chans = READ_ONCE(intf->channel_list)->c;
1949
1950         if (chans[addr->channel].medium != IPMI_CHANNEL_MEDIUM_IPMB) {
1951                 ipmi_inc_stat(intf, sent_invalid_commands);
1952                 return -EINVAL;
1953         }
1954
1955         if (addr->addr_type == IPMI_IPMB_BROADCAST_ADDR_TYPE) {
1956                 /*
1957                  * Broadcasts add a zero at the beginning of the
1958                  * message, but otherwise is the same as an IPMB
1959                  * address.
1960                  */
1961                 addr->addr_type = IPMI_IPMB_ADDR_TYPE;
1962                 broadcast = 1;
1963                 retries = 0; /* Don't retry broadcasts. */
1964         }
1965
1966         /*
1967          * 9 for the header and 1 for the checksum, plus
1968          * possibly one for the broadcast.
1969          */
1970         if ((msg->data_len + 10 + broadcast) > IPMI_MAX_MSG_LENGTH) {
1971                 ipmi_inc_stat(intf, sent_invalid_commands);
1972                 return -EMSGSIZE;
1973         }
1974
1975         ipmb_addr = (struct ipmi_ipmb_addr *) addr;
1976         if (ipmb_addr->lun > 3) {
1977                 ipmi_inc_stat(intf, sent_invalid_commands);
1978                 return -EINVAL;
1979         }
1980
1981         memcpy(&recv_msg->addr, ipmb_addr, sizeof(*ipmb_addr));
1982
1983         if (recv_msg->msg.netfn & 0x1) {
1984                 /*
1985                  * It's a response, so use the user's sequence
1986                  * from msgid.
1987                  */
1988                 ipmi_inc_stat(intf, sent_ipmb_responses);
1989                 format_ipmb_msg(smi_msg, msg, ipmb_addr, msgid,
1990                                 msgid, broadcast,
1991                                 source_address, source_lun);
1992
1993                 /*
1994                  * Save the receive message so we can use it
1995                  * to deliver the response.
1996                  */
1997                 smi_msg->user_data = recv_msg;
1998         } else {
1999                 /* It's a command, so get a sequence for it. */
2000                 unsigned long flags;
2001
2002                 spin_lock_irqsave(&intf->seq_lock, flags);
2003
2004                 if (is_maintenance_mode_cmd(msg))
2005                         intf->ipmb_maintenance_mode_timeout =
2006                                 maintenance_mode_timeout_ms;
2007
2008                 if (intf->ipmb_maintenance_mode_timeout && retry_time_ms == 0)
2009                         /* Different default in maintenance mode */
2010                         retry_time_ms = default_maintenance_retry_ms;
2011
2012                 /*
2013                  * Create a sequence number with a 1 second
2014                  * timeout and 4 retries.
2015                  */
2016                 rv = intf_next_seq(intf,
2017                                    recv_msg,
2018                                    retry_time_ms,
2019                                    retries,
2020                                    broadcast,
2021                                    &ipmb_seq,
2022                                    &seqid);
2023                 if (rv)
2024                         /*
2025                          * We have used up all the sequence numbers,
2026                          * probably, so abort.
2027                          */
2028                         goto out_err;
2029
2030                 ipmi_inc_stat(intf, sent_ipmb_commands);
2031
2032                 /*
2033                  * Store the sequence number in the message,
2034                  * so that when the send message response
2035                  * comes back we can start the timer.
2036                  */
2037                 format_ipmb_msg(smi_msg, msg, ipmb_addr,
2038                                 STORE_SEQ_IN_MSGID(ipmb_seq, seqid),
2039                                 ipmb_seq, broadcast,
2040                                 source_address, source_lun);
2041
2042                 /*
2043                  * Copy the message into the recv message data, so we
2044                  * can retransmit it later if necessary.
2045                  */
2046                 memcpy(recv_msg->msg_data, smi_msg->data,
2047                        smi_msg->data_size);
2048                 recv_msg->msg.data = recv_msg->msg_data;
2049                 recv_msg->msg.data_len = smi_msg->data_size;
2050
2051                 /*
2052                  * We don't unlock until here, because we need
2053                  * to copy the completed message into the
2054                  * recv_msg before we release the lock.
2055                  * Otherwise, race conditions may bite us.  I
2056                  * know that's pretty paranoid, but I prefer
2057                  * to be correct.
2058                  */
2059 out_err:
2060                 spin_unlock_irqrestore(&intf->seq_lock, flags);
2061         }
2062
2063         return rv;
2064 }
2065
2066 static int i_ipmi_req_lan(struct ipmi_smi        *intf,
2067                           struct ipmi_addr       *addr,
2068                           long                   msgid,
2069                           struct kernel_ipmi_msg *msg,
2070                           struct ipmi_smi_msg    *smi_msg,
2071                           struct ipmi_recv_msg   *recv_msg,
2072                           unsigned char          source_lun,
2073                           int                    retries,
2074                           unsigned int           retry_time_ms)
2075 {
2076         struct ipmi_lan_addr  *lan_addr;
2077         unsigned char ipmb_seq;
2078         long seqid;
2079         struct ipmi_channel *chans;
2080         int rv = 0;
2081
2082         if (addr->channel >= IPMI_MAX_CHANNELS) {
2083                 ipmi_inc_stat(intf, sent_invalid_commands);
2084                 return -EINVAL;
2085         }
2086
2087         chans = READ_ONCE(intf->channel_list)->c;
2088
2089         if ((chans[addr->channel].medium
2090                                 != IPMI_CHANNEL_MEDIUM_8023LAN)
2091                         && (chans[addr->channel].medium
2092                             != IPMI_CHANNEL_MEDIUM_ASYNC)) {
2093                 ipmi_inc_stat(intf, sent_invalid_commands);
2094                 return -EINVAL;
2095         }
2096
2097         /* 11 for the header and 1 for the checksum. */
2098         if ((msg->data_len + 12) > IPMI_MAX_MSG_LENGTH) {
2099                 ipmi_inc_stat(intf, sent_invalid_commands);
2100                 return -EMSGSIZE;
2101         }
2102
2103         lan_addr = (struct ipmi_lan_addr *) addr;
2104         if (lan_addr->lun > 3) {
2105                 ipmi_inc_stat(intf, sent_invalid_commands);
2106                 return -EINVAL;
2107         }
2108
2109         memcpy(&recv_msg->addr, lan_addr, sizeof(*lan_addr));
2110
2111         if (recv_msg->msg.netfn & 0x1) {
2112                 /*
2113                  * It's a response, so use the user's sequence
2114                  * from msgid.
2115                  */
2116                 ipmi_inc_stat(intf, sent_lan_responses);
2117                 format_lan_msg(smi_msg, msg, lan_addr, msgid,
2118                                msgid, source_lun);
2119
2120                 /*
2121                  * Save the receive message so we can use it
2122                  * to deliver the response.
2123                  */
2124                 smi_msg->user_data = recv_msg;
2125         } else {
2126                 /* It's a command, so get a sequence for it. */
2127                 unsigned long flags;
2128
2129                 spin_lock_irqsave(&intf->seq_lock, flags);
2130
2131                 /*
2132                  * Create a sequence number with a 1 second
2133                  * timeout and 4 retries.
2134                  */
2135                 rv = intf_next_seq(intf,
2136                                    recv_msg,
2137                                    retry_time_ms,
2138                                    retries,
2139                                    0,
2140                                    &ipmb_seq,
2141                                    &seqid);
2142                 if (rv)
2143                         /*
2144                          * We have used up all the sequence numbers,
2145                          * probably, so abort.
2146                          */
2147                         goto out_err;
2148
2149                 ipmi_inc_stat(intf, sent_lan_commands);
2150
2151                 /*
2152                  * Store the sequence number in the message,
2153                  * so that when the send message response
2154                  * comes back we can start the timer.
2155                  */
2156                 format_lan_msg(smi_msg, msg, lan_addr,
2157                                STORE_SEQ_IN_MSGID(ipmb_seq, seqid),
2158                                ipmb_seq, source_lun);
2159
2160                 /*
2161                  * Copy the message into the recv message data, so we
2162                  * can retransmit it later if necessary.
2163                  */
2164                 memcpy(recv_msg->msg_data, smi_msg->data,
2165                        smi_msg->data_size);
2166                 recv_msg->msg.data = recv_msg->msg_data;
2167                 recv_msg->msg.data_len = smi_msg->data_size;
2168
2169                 /*
2170                  * We don't unlock until here, because we need
2171                  * to copy the completed message into the
2172                  * recv_msg before we release the lock.
2173                  * Otherwise, race conditions may bite us.  I
2174                  * know that's pretty paranoid, but I prefer
2175                  * to be correct.
2176                  */
2177 out_err:
2178                 spin_unlock_irqrestore(&intf->seq_lock, flags);
2179         }
2180
2181         return rv;
2182 }
2183
2184 /*
2185  * Separate from ipmi_request so that the user does not have to be
2186  * supplied in certain circumstances (mainly at panic time).  If
2187  * messages are supplied, they will be freed, even if an error
2188  * occurs.
2189  */
2190 static int i_ipmi_request(struct ipmi_user     *user,
2191                           struct ipmi_smi      *intf,
2192                           struct ipmi_addr     *addr,
2193                           long                 msgid,
2194                           struct kernel_ipmi_msg *msg,
2195                           void                 *user_msg_data,
2196                           void                 *supplied_smi,
2197                           struct ipmi_recv_msg *supplied_recv,
2198                           int                  priority,
2199                           unsigned char        source_address,
2200                           unsigned char        source_lun,
2201                           int                  retries,
2202                           unsigned int         retry_time_ms)
2203 {
2204         struct ipmi_smi_msg *smi_msg;
2205         struct ipmi_recv_msg *recv_msg;
2206         int rv = 0;
2207
2208         if (supplied_recv)
2209                 recv_msg = supplied_recv;
2210         else {
2211                 recv_msg = ipmi_alloc_recv_msg();
2212                 if (recv_msg == NULL) {
2213                         rv = -ENOMEM;
2214                         goto out;
2215                 }
2216         }
2217         recv_msg->user_msg_data = user_msg_data;
2218
2219         if (supplied_smi)
2220                 smi_msg = (struct ipmi_smi_msg *) supplied_smi;
2221         else {
2222                 smi_msg = ipmi_alloc_smi_msg();
2223                 if (smi_msg == NULL) {
2224                         if (!supplied_recv)
2225                                 ipmi_free_recv_msg(recv_msg);
2226                         rv = -ENOMEM;
2227                         goto out;
2228                 }
2229         }
2230
2231         rcu_read_lock();
2232         if (intf->in_shutdown) {
2233                 rv = -ENODEV;
2234                 goto out_err;
2235         }
2236
2237         recv_msg->user = user;
2238         if (user)
2239                 /* The put happens when the message is freed. */
2240                 kref_get(&user->refcount);
2241         recv_msg->msgid = msgid;
2242         /*
2243          * Store the message to send in the receive message so timeout
2244          * responses can get the proper response data.
2245          */
2246         recv_msg->msg = *msg;
2247
2248         if (addr->addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE) {
2249                 rv = i_ipmi_req_sysintf(intf, addr, msgid, msg, smi_msg,
2250                                         recv_msg, retries, retry_time_ms);
2251         } else if (is_ipmb_addr(addr) || is_ipmb_bcast_addr(addr)) {
2252                 rv = i_ipmi_req_ipmb(intf, addr, msgid, msg, smi_msg, recv_msg,
2253                                      source_address, source_lun,
2254                                      retries, retry_time_ms);
2255         } else if (is_lan_addr(addr)) {
2256                 rv = i_ipmi_req_lan(intf, addr, msgid, msg, smi_msg, recv_msg,
2257                                     source_lun, retries, retry_time_ms);
2258         } else {
2259             /* Unknown address type. */
2260                 ipmi_inc_stat(intf, sent_invalid_commands);
2261                 rv = -EINVAL;
2262         }
2263
2264         if (rv) {
2265 out_err:
2266                 ipmi_free_smi_msg(smi_msg);
2267                 ipmi_free_recv_msg(recv_msg);
2268         } else {
2269                 pr_debug("Send: %*ph\n", smi_msg->data_size, smi_msg->data);
2270
2271                 smi_send(intf, intf->handlers, smi_msg, priority);
2272         }
2273         rcu_read_unlock();
2274
2275 out:
2276         return rv;
2277 }
2278
2279 static int check_addr(struct ipmi_smi  *intf,
2280                       struct ipmi_addr *addr,
2281                       unsigned char    *saddr,
2282                       unsigned char    *lun)
2283 {
2284         if (addr->channel >= IPMI_MAX_CHANNELS)
2285                 return -EINVAL;
2286         addr->channel = array_index_nospec(addr->channel, IPMI_MAX_CHANNELS);
2287         *lun = intf->addrinfo[addr->channel].lun;
2288         *saddr = intf->addrinfo[addr->channel].address;
2289         return 0;
2290 }
2291
2292 int ipmi_request_settime(struct ipmi_user *user,
2293                          struct ipmi_addr *addr,
2294                          long             msgid,
2295                          struct kernel_ipmi_msg  *msg,
2296                          void             *user_msg_data,
2297                          int              priority,
2298                          int              retries,
2299                          unsigned int     retry_time_ms)
2300 {
2301         unsigned char saddr = 0, lun = 0;
2302         int rv, index;
2303
2304         if (!user)
2305                 return -EINVAL;
2306
2307         user = acquire_ipmi_user(user, &index);
2308         if (!user)
2309                 return -ENODEV;
2310
2311         rv = check_addr(user->intf, addr, &saddr, &lun);
2312         if (!rv)
2313                 rv = i_ipmi_request(user,
2314                                     user->intf,
2315                                     addr,
2316                                     msgid,
2317                                     msg,
2318                                     user_msg_data,
2319                                     NULL, NULL,
2320                                     priority,
2321                                     saddr,
2322                                     lun,
2323                                     retries,
2324                                     retry_time_ms);
2325
2326         release_ipmi_user(user, index);
2327         return rv;
2328 }
2329 EXPORT_SYMBOL(ipmi_request_settime);
2330
2331 int ipmi_request_supply_msgs(struct ipmi_user     *user,
2332                              struct ipmi_addr     *addr,
2333                              long                 msgid,
2334                              struct kernel_ipmi_msg *msg,
2335                              void                 *user_msg_data,
2336                              void                 *supplied_smi,
2337                              struct ipmi_recv_msg *supplied_recv,
2338                              int                  priority)
2339 {
2340         unsigned char saddr = 0, lun = 0;
2341         int rv, index;
2342
2343         if (!user)
2344                 return -EINVAL;
2345
2346         user = acquire_ipmi_user(user, &index);
2347         if (!user)
2348                 return -ENODEV;
2349
2350         rv = check_addr(user->intf, addr, &saddr, &lun);
2351         if (!rv)
2352                 rv = i_ipmi_request(user,
2353                                     user->intf,
2354                                     addr,
2355                                     msgid,
2356                                     msg,
2357                                     user_msg_data,
2358                                     supplied_smi,
2359                                     supplied_recv,
2360                                     priority,
2361                                     saddr,
2362                                     lun,
2363                                     -1, 0);
2364
2365         release_ipmi_user(user, index);
2366         return rv;
2367 }
2368 EXPORT_SYMBOL(ipmi_request_supply_msgs);
2369
2370 static void bmc_device_id_handler(struct ipmi_smi *intf,
2371                                   struct ipmi_recv_msg *msg)
2372 {
2373         int rv;
2374
2375         if ((msg->addr.addr_type != IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
2376                         || (msg->msg.netfn != IPMI_NETFN_APP_RESPONSE)
2377                         || (msg->msg.cmd != IPMI_GET_DEVICE_ID_CMD)) {
2378                 dev_warn(intf->si_dev,
2379                          "invalid device_id msg: addr_type=%d netfn=%x cmd=%x\n",
2380                          msg->addr.addr_type, msg->msg.netfn, msg->msg.cmd);
2381                 return;
2382         }
2383
2384         rv = ipmi_demangle_device_id(msg->msg.netfn, msg->msg.cmd,
2385                         msg->msg.data, msg->msg.data_len, &intf->bmc->fetch_id);
2386         if (rv) {
2387                 dev_warn(intf->si_dev, "device id demangle failed: %d\n", rv);
2388                 /* record completion code when error */
2389                 intf->bmc->cc = msg->msg.data[0];
2390                 intf->bmc->dyn_id_set = 0;
2391         } else {
2392                 /*
2393                  * Make sure the id data is available before setting
2394                  * dyn_id_set.
2395                  */
2396                 smp_wmb();
2397                 intf->bmc->dyn_id_set = 1;
2398         }
2399
2400         wake_up(&intf->waitq);
2401 }
2402
2403 static int
2404 send_get_device_id_cmd(struct ipmi_smi *intf)
2405 {
2406         struct ipmi_system_interface_addr si;
2407         struct kernel_ipmi_msg msg;
2408
2409         si.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
2410         si.channel = IPMI_BMC_CHANNEL;
2411         si.lun = 0;
2412
2413         msg.netfn = IPMI_NETFN_APP_REQUEST;
2414         msg.cmd = IPMI_GET_DEVICE_ID_CMD;
2415         msg.data = NULL;
2416         msg.data_len = 0;
2417
2418         return i_ipmi_request(NULL,
2419                               intf,
2420                               (struct ipmi_addr *) &si,
2421                               0,
2422                               &msg,
2423                               intf,
2424                               NULL,
2425                               NULL,
2426                               0,
2427                               intf->addrinfo[0].address,
2428                               intf->addrinfo[0].lun,
2429                               -1, 0);
2430 }
2431
2432 static int __get_device_id(struct ipmi_smi *intf, struct bmc_device *bmc)
2433 {
2434         int rv;
2435         unsigned int retry_count = 0;
2436
2437         intf->null_user_handler = bmc_device_id_handler;
2438
2439 retry:
2440         bmc->cc = 0;
2441         bmc->dyn_id_set = 2;
2442
2443         rv = send_get_device_id_cmd(intf);
2444         if (rv)
2445                 goto out_reset_handler;
2446
2447         wait_event(intf->waitq, bmc->dyn_id_set != 2);
2448
2449         if (!bmc->dyn_id_set) {
2450                 if ((bmc->cc == IPMI_DEVICE_IN_FW_UPDATE_ERR
2451                      || bmc->cc ==  IPMI_DEVICE_IN_INIT_ERR
2452                      || bmc->cc ==  IPMI_NOT_IN_MY_STATE_ERR)
2453                      && ++retry_count <= GET_DEVICE_ID_MAX_RETRY) {
2454                         msleep(500);
2455                         dev_warn(intf->si_dev,
2456                             "BMC returned 0x%2.2x, retry get bmc device id\n",
2457                             bmc->cc);
2458                         goto retry;
2459                 }
2460
2461                 rv = -EIO; /* Something went wrong in the fetch. */
2462         }
2463
2464         /* dyn_id_set makes the id data available. */
2465         smp_rmb();
2466
2467 out_reset_handler:
2468         intf->null_user_handler = NULL;
2469
2470         return rv;
2471 }
2472
2473 /*
2474  * Fetch the device id for the bmc/interface.  You must pass in either
2475  * bmc or intf, this code will get the other one.  If the data has
2476  * been recently fetched, this will just use the cached data.  Otherwise
2477  * it will run a new fetch.
2478  *
2479  * Except for the first time this is called (in ipmi_add_smi()),
2480  * this will always return good data;
2481  */
2482 static int __bmc_get_device_id(struct ipmi_smi *intf, struct bmc_device *bmc,
2483                                struct ipmi_device_id *id,
2484                                bool *guid_set, guid_t *guid, int intf_num)
2485 {
2486         int rv = 0;
2487         int prev_dyn_id_set, prev_guid_set;
2488         bool intf_set = intf != NULL;
2489
2490         if (!intf) {
2491                 mutex_lock(&bmc->dyn_mutex);
2492 retry_bmc_lock:
2493                 if (list_empty(&bmc->intfs)) {
2494                         mutex_unlock(&bmc->dyn_mutex);
2495                         return -ENOENT;
2496                 }
2497                 intf = list_first_entry(&bmc->intfs, struct ipmi_smi,
2498                                         bmc_link);
2499                 kref_get(&intf->refcount);
2500                 mutex_unlock(&bmc->dyn_mutex);
2501                 mutex_lock(&intf->bmc_reg_mutex);
2502                 mutex_lock(&bmc->dyn_mutex);
2503                 if (intf != list_first_entry(&bmc->intfs, struct ipmi_smi,
2504                                              bmc_link)) {
2505                         mutex_unlock(&intf->bmc_reg_mutex);
2506                         kref_put(&intf->refcount, intf_free);
2507                         goto retry_bmc_lock;
2508                 }
2509         } else {
2510                 mutex_lock(&intf->bmc_reg_mutex);
2511                 bmc = intf->bmc;
2512                 mutex_lock(&bmc->dyn_mutex);
2513                 kref_get(&intf->refcount);
2514         }
2515
2516         /* If we have a valid and current ID, just return that. */
2517         if (intf->in_bmc_register ||
2518             (bmc->dyn_id_set && time_is_after_jiffies(bmc->dyn_id_expiry)))
2519                 goto out_noprocessing;
2520
2521         prev_guid_set = bmc->dyn_guid_set;
2522         __get_guid(intf);
2523
2524         prev_dyn_id_set = bmc->dyn_id_set;
2525         rv = __get_device_id(intf, bmc);
2526         if (rv)
2527                 goto out;
2528
2529         /*
2530          * The guid, device id, manufacturer id, and product id should
2531          * not change on a BMC.  If it does we have to do some dancing.
2532          */
2533         if (!intf->bmc_registered
2534             || (!prev_guid_set && bmc->dyn_guid_set)
2535             || (!prev_dyn_id_set && bmc->dyn_id_set)
2536             || (prev_guid_set && bmc->dyn_guid_set
2537                 && !guid_equal(&bmc->guid, &bmc->fetch_guid))
2538             || bmc->id.device_id != bmc->fetch_id.device_id
2539             || bmc->id.manufacturer_id != bmc->fetch_id.manufacturer_id
2540             || bmc->id.product_id != bmc->fetch_id.product_id) {
2541                 struct ipmi_device_id id = bmc->fetch_id;
2542                 int guid_set = bmc->dyn_guid_set;
2543                 guid_t guid;
2544
2545                 guid = bmc->fetch_guid;
2546                 mutex_unlock(&bmc->dyn_mutex);
2547
2548                 __ipmi_bmc_unregister(intf);
2549                 /* Fill in the temporary BMC for good measure. */
2550                 intf->bmc->id = id;
2551                 intf->bmc->dyn_guid_set = guid_set;
2552                 intf->bmc->guid = guid;
2553                 if (__ipmi_bmc_register(intf, &id, guid_set, &guid, intf_num))
2554                         need_waiter(intf); /* Retry later on an error. */
2555                 else
2556                         __scan_channels(intf, &id);
2557
2558
2559                 if (!intf_set) {
2560                         /*
2561                          * We weren't given the interface on the
2562                          * command line, so restart the operation on
2563                          * the next interface for the BMC.
2564                          */
2565                         mutex_unlock(&intf->bmc_reg_mutex);
2566                         mutex_lock(&bmc->dyn_mutex);
2567                         goto retry_bmc_lock;
2568                 }
2569
2570                 /* We have a new BMC, set it up. */
2571                 bmc = intf->bmc;
2572                 mutex_lock(&bmc->dyn_mutex);
2573                 goto out_noprocessing;
2574         } else if (memcmp(&bmc->fetch_id, &bmc->id, sizeof(bmc->id)))
2575                 /* Version info changes, scan the channels again. */
2576                 __scan_channels(intf, &bmc->fetch_id);
2577
2578         bmc->dyn_id_expiry = jiffies + IPMI_DYN_DEV_ID_EXPIRY;
2579
2580 out:
2581         if (rv && prev_dyn_id_set) {
2582                 rv = 0; /* Ignore failures if we have previous data. */
2583                 bmc->dyn_id_set = prev_dyn_id_set;
2584         }
2585         if (!rv) {
2586                 bmc->id = bmc->fetch_id;
2587                 if (bmc->dyn_guid_set)
2588                         bmc->guid = bmc->fetch_guid;
2589                 else if (prev_guid_set)
2590                         /*
2591                          * The guid used to be valid and it failed to fetch,
2592                          * just use the cached value.
2593                          */
2594                         bmc->dyn_guid_set = prev_guid_set;
2595         }
2596 out_noprocessing:
2597         if (!rv) {
2598                 if (id)
2599                         *id = bmc->id;
2600
2601                 if (guid_set)
2602                         *guid_set = bmc->dyn_guid_set;
2603
2604                 if (guid && bmc->dyn_guid_set)
2605                         *guid =  bmc->guid;
2606         }
2607
2608         mutex_unlock(&bmc->dyn_mutex);
2609         mutex_unlock(&intf->bmc_reg_mutex);
2610
2611         kref_put(&intf->refcount, intf_free);
2612         return rv;
2613 }
2614
2615 static int bmc_get_device_id(struct ipmi_smi *intf, struct bmc_device *bmc,
2616                              struct ipmi_device_id *id,
2617                              bool *guid_set, guid_t *guid)
2618 {
2619         return __bmc_get_device_id(intf, bmc, id, guid_set, guid, -1);
2620 }
2621
2622 static ssize_t device_id_show(struct device *dev,
2623                               struct device_attribute *attr,
2624                               char *buf)
2625 {
2626         struct bmc_device *bmc = to_bmc_device(dev);
2627         struct ipmi_device_id id;
2628         int rv;
2629
2630         rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2631         if (rv)
2632                 return rv;
2633
2634         return snprintf(buf, 10, "%u\n", id.device_id);
2635 }
2636 static DEVICE_ATTR_RO(device_id);
2637
2638 static ssize_t provides_device_sdrs_show(struct device *dev,
2639                                          struct device_attribute *attr,
2640                                          char *buf)
2641 {
2642         struct bmc_device *bmc = to_bmc_device(dev);
2643         struct ipmi_device_id id;
2644         int rv;
2645
2646         rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2647         if (rv)
2648                 return rv;
2649
2650         return snprintf(buf, 10, "%u\n", (id.device_revision & 0x80) >> 7);
2651 }
2652 static DEVICE_ATTR_RO(provides_device_sdrs);
2653
2654 static ssize_t revision_show(struct device *dev, struct device_attribute *attr,
2655                              char *buf)
2656 {
2657         struct bmc_device *bmc = to_bmc_device(dev);
2658         struct ipmi_device_id id;
2659         int rv;
2660
2661         rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2662         if (rv)
2663                 return rv;
2664
2665         return snprintf(buf, 20, "%u\n", id.device_revision & 0x0F);
2666 }
2667 static DEVICE_ATTR_RO(revision);
2668
2669 static ssize_t firmware_revision_show(struct device *dev,
2670                                       struct device_attribute *attr,
2671                                       char *buf)
2672 {
2673         struct bmc_device *bmc = to_bmc_device(dev);
2674         struct ipmi_device_id id;
2675         int rv;
2676
2677         rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2678         if (rv)
2679                 return rv;
2680
2681         return snprintf(buf, 20, "%u.%x\n", id.firmware_revision_1,
2682                         id.firmware_revision_2);
2683 }
2684 static DEVICE_ATTR_RO(firmware_revision);
2685
2686 static ssize_t ipmi_version_show(struct device *dev,
2687                                  struct device_attribute *attr,
2688                                  char *buf)
2689 {
2690         struct bmc_device *bmc = to_bmc_device(dev);
2691         struct ipmi_device_id id;
2692         int rv;
2693
2694         rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2695         if (rv)
2696                 return rv;
2697
2698         return snprintf(buf, 20, "%u.%u\n",
2699                         ipmi_version_major(&id),
2700                         ipmi_version_minor(&id));
2701 }
2702 static DEVICE_ATTR_RO(ipmi_version);
2703
2704 static ssize_t add_dev_support_show(struct device *dev,
2705                                     struct device_attribute *attr,
2706                                     char *buf)
2707 {
2708         struct bmc_device *bmc = to_bmc_device(dev);
2709         struct ipmi_device_id id;
2710         int rv;
2711
2712         rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2713         if (rv)
2714                 return rv;
2715
2716         return snprintf(buf, 10, "0x%02x\n", id.additional_device_support);
2717 }
2718 static DEVICE_ATTR(additional_device_support, S_IRUGO, add_dev_support_show,
2719                    NULL);
2720
2721 static ssize_t manufacturer_id_show(struct device *dev,
2722                                     struct device_attribute *attr,
2723                                     char *buf)
2724 {
2725         struct bmc_device *bmc = to_bmc_device(dev);
2726         struct ipmi_device_id id;
2727         int rv;
2728
2729         rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2730         if (rv)
2731                 return rv;
2732
2733         return snprintf(buf, 20, "0x%6.6x\n", id.manufacturer_id);
2734 }
2735 static DEVICE_ATTR_RO(manufacturer_id);
2736
2737 static ssize_t product_id_show(struct device *dev,
2738                                struct device_attribute *attr,
2739                                char *buf)
2740 {
2741         struct bmc_device *bmc = to_bmc_device(dev);
2742         struct ipmi_device_id id;
2743         int rv;
2744
2745         rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2746         if (rv)
2747                 return rv;
2748
2749         return snprintf(buf, 10, "0x%4.4x\n", id.product_id);
2750 }
2751 static DEVICE_ATTR_RO(product_id);
2752
2753 static ssize_t aux_firmware_rev_show(struct device *dev,
2754                                      struct device_attribute *attr,
2755                                      char *buf)
2756 {
2757         struct bmc_device *bmc = to_bmc_device(dev);
2758         struct ipmi_device_id id;
2759         int rv;
2760
2761         rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2762         if (rv)
2763                 return rv;
2764
2765         return snprintf(buf, 21, "0x%02x 0x%02x 0x%02x 0x%02x\n",
2766                         id.aux_firmware_revision[3],
2767                         id.aux_firmware_revision[2],
2768                         id.aux_firmware_revision[1],
2769                         id.aux_firmware_revision[0]);
2770 }
2771 static DEVICE_ATTR(aux_firmware_revision, S_IRUGO, aux_firmware_rev_show, NULL);
2772
2773 static ssize_t guid_show(struct device *dev, struct device_attribute *attr,
2774                          char *buf)
2775 {
2776         struct bmc_device *bmc = to_bmc_device(dev);
2777         bool guid_set;
2778         guid_t guid;
2779         int rv;
2780
2781         rv = bmc_get_device_id(NULL, bmc, NULL, &guid_set, &guid);
2782         if (rv)
2783                 return rv;
2784         if (!guid_set)
2785                 return -ENOENT;
2786
2787         return snprintf(buf, UUID_STRING_LEN + 1 + 1, "%pUl\n", &guid);
2788 }
2789 static DEVICE_ATTR_RO(guid);
2790
2791 static struct attribute *bmc_dev_attrs[] = {
2792         &dev_attr_device_id.attr,
2793         &dev_attr_provides_device_sdrs.attr,
2794         &dev_attr_revision.attr,
2795         &dev_attr_firmware_revision.attr,
2796         &dev_attr_ipmi_version.attr,
2797         &dev_attr_additional_device_support.attr,
2798         &dev_attr_manufacturer_id.attr,
2799         &dev_attr_product_id.attr,
2800         &dev_attr_aux_firmware_revision.attr,
2801         &dev_attr_guid.attr,
2802         NULL
2803 };
2804
2805 static umode_t bmc_dev_attr_is_visible(struct kobject *kobj,
2806                                        struct attribute *attr, int idx)
2807 {
2808         struct device *dev = kobj_to_dev(kobj);
2809         struct bmc_device *bmc = to_bmc_device(dev);
2810         umode_t mode = attr->mode;
2811         int rv;
2812
2813         if (attr == &dev_attr_aux_firmware_revision.attr) {
2814                 struct ipmi_device_id id;
2815
2816                 rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2817                 return (!rv && id.aux_firmware_revision_set) ? mode : 0;
2818         }
2819         if (attr == &dev_attr_guid.attr) {
2820                 bool guid_set;
2821
2822                 rv = bmc_get_device_id(NULL, bmc, NULL, &guid_set, NULL);
2823                 return (!rv && guid_set) ? mode : 0;
2824         }
2825         return mode;
2826 }
2827
2828 static const struct attribute_group bmc_dev_attr_group = {
2829         .attrs          = bmc_dev_attrs,
2830         .is_visible     = bmc_dev_attr_is_visible,
2831 };
2832
2833 static const struct attribute_group *bmc_dev_attr_groups[] = {
2834         &bmc_dev_attr_group,
2835         NULL
2836 };
2837
2838 static const struct device_type bmc_device_type = {
2839         .groups         = bmc_dev_attr_groups,
2840 };
2841
2842 static int __find_bmc_guid(struct device *dev, const void *data)
2843 {
2844         const guid_t *guid = data;
2845         struct bmc_device *bmc;
2846         int rv;
2847
2848         if (dev->type != &bmc_device_type)
2849                 return 0;
2850
2851         bmc = to_bmc_device(dev);
2852         rv = bmc->dyn_guid_set && guid_equal(&bmc->guid, guid);
2853         if (rv)
2854                 rv = kref_get_unless_zero(&bmc->usecount);
2855         return rv;
2856 }
2857
2858 /*
2859  * Returns with the bmc's usecount incremented, if it is non-NULL.
2860  */
2861 static struct bmc_device *ipmi_find_bmc_guid(struct device_driver *drv,
2862                                              guid_t *guid)
2863 {
2864         struct device *dev;
2865         struct bmc_device *bmc = NULL;
2866
2867         dev = driver_find_device(drv, NULL, guid, __find_bmc_guid);
2868         if (dev) {
2869                 bmc = to_bmc_device(dev);
2870                 put_device(dev);
2871         }
2872         return bmc;
2873 }
2874
2875 struct prod_dev_id {
2876         unsigned int  product_id;
2877         unsigned char device_id;
2878 };
2879
2880 static int __find_bmc_prod_dev_id(struct device *dev, const void *data)
2881 {
2882         const struct prod_dev_id *cid = data;
2883         struct bmc_device *bmc;
2884         int rv;
2885
2886         if (dev->type != &bmc_device_type)
2887                 return 0;
2888
2889         bmc = to_bmc_device(dev);
2890         rv = (bmc->id.product_id == cid->product_id
2891               && bmc->id.device_id == cid->device_id);
2892         if (rv)
2893                 rv = kref_get_unless_zero(&bmc->usecount);
2894         return rv;
2895 }
2896
2897 /*
2898  * Returns with the bmc's usecount incremented, if it is non-NULL.
2899  */
2900 static struct bmc_device *ipmi_find_bmc_prod_dev_id(
2901         struct device_driver *drv,
2902         unsigned int product_id, unsigned char device_id)
2903 {
2904         struct prod_dev_id id = {
2905                 .product_id = product_id,
2906                 .device_id = device_id,
2907         };
2908         struct device *dev;
2909         struct bmc_device *bmc = NULL;
2910
2911         dev = driver_find_device(drv, NULL, &id, __find_bmc_prod_dev_id);
2912         if (dev) {
2913                 bmc = to_bmc_device(dev);
2914                 put_device(dev);
2915         }
2916         return bmc;
2917 }
2918
2919 static DEFINE_IDA(ipmi_bmc_ida);
2920
2921 static void
2922 release_bmc_device(struct device *dev)
2923 {
2924         kfree(to_bmc_device(dev));
2925 }
2926
2927 static void cleanup_bmc_work(struct work_struct *work)
2928 {
2929         struct bmc_device *bmc = container_of(work, struct bmc_device,
2930                                               remove_work);
2931         int id = bmc->pdev.id; /* Unregister overwrites id */
2932
2933         platform_device_unregister(&bmc->pdev);
2934         ida_simple_remove(&ipmi_bmc_ida, id);
2935 }
2936
2937 static void
2938 cleanup_bmc_device(struct kref *ref)
2939 {
2940         struct bmc_device *bmc = container_of(ref, struct bmc_device, usecount);
2941
2942         /*
2943          * Remove the platform device in a work queue to avoid issues
2944          * with removing the device attributes while reading a device
2945          * attribute.
2946          */
2947         schedule_work(&bmc->remove_work);
2948 }
2949
2950 /*
2951  * Must be called with intf->bmc_reg_mutex held.
2952  */
2953 static void __ipmi_bmc_unregister(struct ipmi_smi *intf)
2954 {
2955         struct bmc_device *bmc = intf->bmc;
2956
2957         if (!intf->bmc_registered)
2958                 return;
2959
2960         sysfs_remove_link(&intf->si_dev->kobj, "bmc");
2961         sysfs_remove_link(&bmc->pdev.dev.kobj, intf->my_dev_name);
2962         kfree(intf->my_dev_name);
2963         intf->my_dev_name = NULL;
2964
2965         mutex_lock(&bmc->dyn_mutex);
2966         list_del(&intf->bmc_link);
2967         mutex_unlock(&bmc->dyn_mutex);
2968         intf->bmc = &intf->tmp_bmc;
2969         kref_put(&bmc->usecount, cleanup_bmc_device);
2970         intf->bmc_registered = false;
2971 }
2972
2973 static void ipmi_bmc_unregister(struct ipmi_smi *intf)
2974 {
2975         mutex_lock(&intf->bmc_reg_mutex);
2976         __ipmi_bmc_unregister(intf);
2977         mutex_unlock(&intf->bmc_reg_mutex);
2978 }
2979
2980 /*
2981  * Must be called with intf->bmc_reg_mutex held.
2982  */
2983 static int __ipmi_bmc_register(struct ipmi_smi *intf,
2984                                struct ipmi_device_id *id,
2985                                bool guid_set, guid_t *guid, int intf_num)
2986 {
2987         int               rv;
2988         struct bmc_device *bmc;
2989         struct bmc_device *old_bmc;
2990
2991         /*
2992          * platform_device_register() can cause bmc_reg_mutex to
2993          * be claimed because of the is_visible functions of
2994          * the attributes.  Eliminate possible recursion and
2995          * release the lock.
2996          */
2997         intf->in_bmc_register = true;
2998         mutex_unlock(&intf->bmc_reg_mutex);
2999
3000         /*
3001          * Try to find if there is an bmc_device struct
3002          * representing the interfaced BMC already
3003          */
3004         mutex_lock(&ipmidriver_mutex);
3005         if (guid_set)
3006                 old_bmc = ipmi_find_bmc_guid(&ipmidriver.driver, guid);
3007         else
3008                 old_bmc = ipmi_find_bmc_prod_dev_id(&ipmidriver.driver,
3009                                                     id->product_id,
3010                                                     id->device_id);
3011
3012         /*
3013          * If there is already an bmc_device, free the new one,
3014          * otherwise register the new BMC device
3015          */
3016         if (old_bmc) {
3017                 bmc = old_bmc;
3018                 /*
3019                  * Note: old_bmc already has usecount incremented by
3020                  * the BMC find functions.
3021                  */
3022                 intf->bmc = old_bmc;
3023                 mutex_lock(&bmc->dyn_mutex);
3024                 list_add_tail(&intf->bmc_link, &bmc->intfs);
3025                 mutex_unlock(&bmc->dyn_mutex);
3026
3027                 dev_info(intf->si_dev,
3028                          "interfacing existing BMC (man_id: 0x%6.6x, prod_id: 0x%4.4x, dev_id: 0x%2.2x)\n",
3029                          bmc->id.manufacturer_id,
3030                          bmc->id.product_id,
3031                          bmc->id.device_id);
3032         } else {
3033                 bmc = kzalloc(sizeof(*bmc), GFP_KERNEL);
3034                 if (!bmc) {
3035                         rv = -ENOMEM;
3036                         goto out;
3037                 }
3038                 INIT_LIST_HEAD(&bmc->intfs);
3039                 mutex_init(&bmc->dyn_mutex);
3040                 INIT_WORK(&bmc->remove_work, cleanup_bmc_work);
3041
3042                 bmc->id = *id;
3043                 bmc->dyn_id_set = 1;
3044                 bmc->dyn_guid_set = guid_set;
3045                 bmc->guid = *guid;
3046                 bmc->dyn_id_expiry = jiffies + IPMI_DYN_DEV_ID_EXPIRY;
3047
3048                 bmc->pdev.name = "ipmi_bmc";
3049
3050                 rv = ida_simple_get(&ipmi_bmc_ida, 0, 0, GFP_KERNEL);
3051                 if (rv < 0) {
3052                         kfree(bmc);
3053                         goto out;
3054                 }
3055
3056                 bmc->pdev.dev.driver = &ipmidriver.driver;
3057                 bmc->pdev.id = rv;
3058                 bmc->pdev.dev.release = release_bmc_device;
3059                 bmc->pdev.dev.type = &bmc_device_type;
3060                 kref_init(&bmc->usecount);
3061
3062                 intf->bmc = bmc;
3063                 mutex_lock(&bmc->dyn_mutex);
3064                 list_add_tail(&intf->bmc_link, &bmc->intfs);
3065                 mutex_unlock(&bmc->dyn_mutex);
3066
3067                 rv = platform_device_register(&bmc->pdev);
3068                 if (rv) {
3069                         dev_err(intf->si_dev,
3070                                 "Unable to register bmc device: %d\n",
3071                                 rv);
3072                         goto out_list_del;
3073                 }
3074
3075                 dev_info(intf->si_dev,
3076                          "Found new BMC (man_id: 0x%6.6x, prod_id: 0x%4.4x, dev_id: 0x%2.2x)\n",
3077                          bmc->id.manufacturer_id,
3078                          bmc->id.product_id,
3079                          bmc->id.device_id);
3080         }
3081
3082         /*
3083          * create symlink from system interface device to bmc device
3084          * and back.
3085          */
3086         rv = sysfs_create_link(&intf->si_dev->kobj, &bmc->pdev.dev.kobj, "bmc");
3087         if (rv) {
3088                 dev_err(intf->si_dev, "Unable to create bmc symlink: %d\n", rv);
3089                 goto out_put_bmc;
3090         }
3091
3092         if (intf_num == -1)
3093                 intf_num = intf->intf_num;
3094         intf->my_dev_name = kasprintf(GFP_KERNEL, "ipmi%d", intf_num);
3095         if (!intf->my_dev_name) {
3096                 rv = -ENOMEM;
3097                 dev_err(intf->si_dev, "Unable to allocate link from BMC: %d\n",
3098                         rv);
3099                 goto out_unlink1;
3100         }
3101
3102         rv = sysfs_create_link(&bmc->pdev.dev.kobj, &intf->si_dev->kobj,
3103                                intf->my_dev_name);
3104         if (rv) {
3105                 dev_err(intf->si_dev, "Unable to create symlink to bmc: %d\n",
3106                         rv);
3107                 goto out_free_my_dev_name;
3108         }
3109
3110         intf->bmc_registered = true;
3111
3112 out:
3113         mutex_unlock(&ipmidriver_mutex);
3114         mutex_lock(&intf->bmc_reg_mutex);
3115         intf->in_bmc_register = false;
3116         return rv;
3117
3118
3119 out_free_my_dev_name:
3120         kfree(intf->my_dev_name);
3121         intf->my_dev_name = NULL;
3122
3123 out_unlink1:
3124         sysfs_remove_link(&intf->si_dev->kobj, "bmc");
3125
3126 out_put_bmc:
3127         mutex_lock(&bmc->dyn_mutex);
3128         list_del(&intf->bmc_link);
3129         mutex_unlock(&bmc->dyn_mutex);
3130         intf->bmc = &intf->tmp_bmc;
3131         kref_put(&bmc->usecount, cleanup_bmc_device);
3132         goto out;
3133
3134 out_list_del:
3135         mutex_lock(&bmc->dyn_mutex);
3136         list_del(&intf->bmc_link);
3137         mutex_unlock(&bmc->dyn_mutex);
3138         intf->bmc = &intf->tmp_bmc;
3139         put_device(&bmc->pdev.dev);
3140         goto out;
3141 }
3142
3143 static int
3144 send_guid_cmd(struct ipmi_smi *intf, int chan)
3145 {
3146         struct kernel_ipmi_msg            msg;
3147         struct ipmi_system_interface_addr si;
3148
3149         si.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
3150         si.channel = IPMI_BMC_CHANNEL;
3151         si.lun = 0;
3152
3153         msg.netfn = IPMI_NETFN_APP_REQUEST;
3154         msg.cmd = IPMI_GET_DEVICE_GUID_CMD;
3155         msg.data = NULL;
3156         msg.data_len = 0;
3157         return i_ipmi_request(NULL,
3158                               intf,
3159                               (struct ipmi_addr *) &si,
3160                               0,
3161                               &msg,
3162                               intf,
3163                               NULL,
3164                               NULL,
3165                               0,
3166                               intf->addrinfo[0].address,
3167                               intf->addrinfo[0].lun,
3168                               -1, 0);
3169 }
3170
3171 static void guid_handler(struct ipmi_smi *intf, struct ipmi_recv_msg *msg)
3172 {
3173         struct bmc_device *bmc = intf->bmc;
3174
3175         if ((msg->addr.addr_type != IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
3176             || (msg->msg.netfn != IPMI_NETFN_APP_RESPONSE)
3177             || (msg->msg.cmd != IPMI_GET_DEVICE_GUID_CMD))
3178                 /* Not for me */
3179                 return;
3180
3181         if (msg->msg.data[0] != 0) {
3182                 /* Error from getting the GUID, the BMC doesn't have one. */
3183                 bmc->dyn_guid_set = 0;
3184                 goto out;
3185         }
3186
3187         if (msg->msg.data_len < UUID_SIZE + 1) {
3188                 bmc->dyn_guid_set = 0;
3189                 dev_warn(intf->si_dev,
3190                          "The GUID response from the BMC was too short, it was %d but should have been %d.  Assuming GUID is not available.\n",
3191                          msg->msg.data_len, UUID_SIZE + 1);
3192                 goto out;
3193         }
3194
3195         import_guid(&bmc->fetch_guid, msg->msg.data + 1);
3196         /*
3197          * Make sure the guid data is available before setting
3198          * dyn_guid_set.
3199          */
3200         smp_wmb();
3201         bmc->dyn_guid_set = 1;
3202  out:
3203         wake_up(&intf->waitq);
3204 }
3205
3206 static void __get_guid(struct ipmi_smi *intf)
3207 {
3208         int rv;
3209         struct bmc_device *bmc = intf->bmc;
3210
3211         bmc->dyn_guid_set = 2;
3212         intf->null_user_handler = guid_handler;
3213         rv = send_guid_cmd(intf, 0);
3214         if (rv)
3215                 /* Send failed, no GUID available. */
3216                 bmc->dyn_guid_set = 0;
3217         else
3218                 wait_event(intf->waitq, bmc->dyn_guid_set != 2);
3219
3220         /* dyn_guid_set makes the guid data available. */
3221         smp_rmb();
3222
3223         intf->null_user_handler = NULL;
3224 }
3225
3226 static int
3227 send_channel_info_cmd(struct ipmi_smi *intf, int chan)
3228 {
3229         struct kernel_ipmi_msg            msg;
3230         unsigned char                     data[1];
3231         struct ipmi_system_interface_addr si;
3232
3233         si.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
3234         si.channel = IPMI_BMC_CHANNEL;
3235         si.lun = 0;
3236
3237         msg.netfn = IPMI_NETFN_APP_REQUEST;
3238         msg.cmd = IPMI_GET_CHANNEL_INFO_CMD;
3239         msg.data = data;
3240         msg.data_len = 1;
3241         data[0] = chan;
3242         return i_ipmi_request(NULL,
3243                               intf,
3244                               (struct ipmi_addr *) &si,
3245                               0,
3246                               &msg,
3247                               intf,
3248                               NULL,
3249                               NULL,
3250                               0,
3251                               intf->addrinfo[0].address,
3252                               intf->addrinfo[0].lun,
3253                               -1, 0);
3254 }
3255
3256 static void
3257 channel_handler(struct ipmi_smi *intf, struct ipmi_recv_msg *msg)
3258 {
3259         int rv = 0;
3260         int ch;
3261         unsigned int set = intf->curr_working_cset;
3262         struct ipmi_channel *chans;
3263
3264         if ((msg->addr.addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
3265             && (msg->msg.netfn == IPMI_NETFN_APP_RESPONSE)
3266             && (msg->msg.cmd == IPMI_GET_CHANNEL_INFO_CMD)) {
3267                 /* It's the one we want */
3268                 if (msg->msg.data[0] != 0) {
3269                         /* Got an error from the channel, just go on. */
3270                         if (msg->msg.data[0] == IPMI_INVALID_COMMAND_ERR) {
3271                                 /*
3272                                  * If the MC does not support this
3273                                  * command, that is legal.  We just
3274                                  * assume it has one IPMB at channel
3275                                  * zero.
3276                                  */
3277                                 intf->wchannels[set].c[0].medium
3278                                         = IPMI_CHANNEL_MEDIUM_IPMB;
3279                                 intf->wchannels[set].c[0].protocol
3280                                         = IPMI_CHANNEL_PROTOCOL_IPMB;
3281
3282                                 intf->channel_list = intf->wchannels + set;
3283                                 intf->channels_ready = true;
3284                                 wake_up(&intf->waitq);
3285                                 goto out;
3286                         }
3287                         goto next_channel;
3288                 }
3289                 if (msg->msg.data_len < 4) {
3290                         /* Message not big enough, just go on. */
3291                         goto next_channel;
3292                 }
3293                 ch = intf->curr_channel;
3294                 chans = intf->wchannels[set].c;
3295                 chans[ch].medium = msg->msg.data[2] & 0x7f;
3296                 chans[ch].protocol = msg->msg.data[3] & 0x1f;
3297
3298  next_channel:
3299                 intf->curr_channel++;
3300                 if (intf->curr_channel >= IPMI_MAX_CHANNELS) {
3301                         intf->channel_list = intf->wchannels + set;
3302                         intf->channels_ready = true;
3303                         wake_up(&intf->waitq);
3304                 } else {
3305                         intf->channel_list = intf->wchannels + set;
3306                         intf->channels_ready = true;
3307                         rv = send_channel_info_cmd(intf, intf->curr_channel);
3308                 }
3309
3310                 if (rv) {
3311                         /* Got an error somehow, just give up. */
3312                         dev_warn(intf->si_dev,
3313                                  "Error sending channel information for channel %d: %d\n",
3314                                  intf->curr_channel, rv);
3315
3316                         intf->channel_list = intf->wchannels + set;
3317                         intf->channels_ready = true;
3318                         wake_up(&intf->waitq);
3319                 }
3320         }
3321  out:
3322         return;
3323 }
3324
3325 /*
3326  * Must be holding intf->bmc_reg_mutex to call this.
3327  */
3328 static int __scan_channels(struct ipmi_smi *intf, struct ipmi_device_id *id)
3329 {
3330         int rv;
3331
3332         if (ipmi_version_major(id) > 1
3333                         || (ipmi_version_major(id) == 1
3334                             && ipmi_version_minor(id) >= 5)) {
3335                 unsigned int set;
3336
3337                 /*
3338                  * Start scanning the channels to see what is
3339                  * available.
3340                  */
3341                 set = !intf->curr_working_cset;
3342                 intf->curr_working_cset = set;
3343                 memset(&intf->wchannels[set], 0,
3344                        sizeof(struct ipmi_channel_set));
3345
3346                 intf->null_user_handler = channel_handler;
3347                 intf->curr_channel = 0;
3348                 rv = send_channel_info_cmd(intf, 0);
3349                 if (rv) {
3350                         dev_warn(intf->si_dev,
3351                                  "Error sending channel information for channel 0, %d\n",
3352                                  rv);
3353                         intf->null_user_handler = NULL;
3354                         return -EIO;
3355                 }
3356
3357                 /* Wait for the channel info to be read. */
3358                 wait_event(intf->waitq, intf->channels_ready);
3359                 intf->null_user_handler = NULL;
3360         } else {
3361                 unsigned int set = intf->curr_working_cset;
3362
3363                 /* Assume a single IPMB channel at zero. */
3364                 intf->wchannels[set].c[0].medium = IPMI_CHANNEL_MEDIUM_IPMB;
3365                 intf->wchannels[set].c[0].protocol = IPMI_CHANNEL_PROTOCOL_IPMB;
3366                 intf->channel_list = intf->wchannels + set;
3367                 intf->channels_ready = true;
3368         }
3369
3370         return 0;
3371 }
3372
3373 static void ipmi_poll(struct ipmi_smi *intf)
3374 {
3375         if (intf->handlers->poll)
3376                 intf->handlers->poll(intf->send_info);
3377         /* In case something came in */
3378         handle_new_recv_msgs(intf);
3379 }
3380
3381 void ipmi_poll_interface(struct ipmi_user *user)
3382 {
3383         ipmi_poll(user->intf);
3384 }
3385 EXPORT_SYMBOL(ipmi_poll_interface);
3386
3387 static void redo_bmc_reg(struct work_struct *work)
3388 {
3389         struct ipmi_smi *intf = container_of(work, struct ipmi_smi,
3390                                              bmc_reg_work);
3391
3392         if (!intf->in_shutdown)
3393                 bmc_get_device_id(intf, NULL, NULL, NULL, NULL);
3394
3395         kref_put(&intf->refcount, intf_free);
3396 }
3397
3398 int ipmi_add_smi(struct module         *owner,
3399                  const struct ipmi_smi_handlers *handlers,
3400                  void                  *send_info,
3401                  struct device         *si_dev,
3402                  unsigned char         slave_addr)
3403 {
3404         int              i, j;
3405         int              rv;
3406         struct ipmi_smi *intf, *tintf;
3407         struct list_head *link;
3408         struct ipmi_device_id id;
3409
3410         /*
3411          * Make sure the driver is actually initialized, this handles
3412          * problems with initialization order.
3413          */
3414         rv = ipmi_init_msghandler();
3415         if (rv)
3416                 return rv;
3417
3418         intf = kzalloc(sizeof(*intf), GFP_KERNEL);
3419         if (!intf)
3420                 return -ENOMEM;
3421
3422         rv = init_srcu_struct(&intf->users_srcu);
3423         if (rv) {
3424                 kfree(intf);
3425                 return rv;
3426         }
3427
3428         intf->owner = owner;
3429         intf->bmc = &intf->tmp_bmc;
3430         INIT_LIST_HEAD(&intf->bmc->intfs);
3431         mutex_init(&intf->bmc->dyn_mutex);
3432         INIT_LIST_HEAD(&intf->bmc_link);
3433         mutex_init(&intf->bmc_reg_mutex);
3434         intf->intf_num = -1; /* Mark it invalid for now. */
3435         kref_init(&intf->refcount);
3436         INIT_WORK(&intf->bmc_reg_work, redo_bmc_reg);
3437         intf->si_dev = si_dev;
3438         for (j = 0; j < IPMI_MAX_CHANNELS; j++) {
3439                 intf->addrinfo[j].address = IPMI_BMC_SLAVE_ADDR;
3440                 intf->addrinfo[j].lun = 2;
3441         }
3442         if (slave_addr != 0)
3443                 intf->addrinfo[0].address = slave_addr;
3444         INIT_LIST_HEAD(&intf->users);
3445         intf->handlers = handlers;
3446         intf->send_info = send_info;
3447         spin_lock_init(&intf->seq_lock);
3448         for (j = 0; j < IPMI_IPMB_NUM_SEQ; j++) {
3449                 intf->seq_table[j].inuse = 0;
3450                 intf->seq_table[j].seqid = 0;
3451         }
3452         intf->curr_seq = 0;
3453         spin_lock_init(&intf->waiting_rcv_msgs_lock);
3454         INIT_LIST_HEAD(&intf->waiting_rcv_msgs);
3455         tasklet_setup(&intf->recv_tasklet,
3456                      smi_recv_tasklet);
3457         atomic_set(&intf->watchdog_pretimeouts_to_deliver, 0);
3458         spin_lock_init(&intf->xmit_msgs_lock);
3459         INIT_LIST_HEAD(&intf->xmit_msgs);
3460         INIT_LIST_HEAD(&intf->hp_xmit_msgs);
3461         spin_lock_init(&intf->events_lock);
3462         spin_lock_init(&intf->watch_lock);
3463         atomic_set(&intf->event_waiters, 0);
3464         intf->ticks_to_req_ev = IPMI_REQUEST_EV_TIME;
3465         INIT_LIST_HEAD(&intf->waiting_events);
3466         intf->waiting_events_count = 0;
3467         mutex_init(&intf->cmd_rcvrs_mutex);
3468         spin_lock_init(&intf->maintenance_mode_lock);
3469         INIT_LIST_HEAD(&intf->cmd_rcvrs);
3470         init_waitqueue_head(&intf->waitq);
3471         for (i = 0; i < IPMI_NUM_STATS; i++)
3472                 atomic_set(&intf->stats[i], 0);
3473
3474         mutex_lock(&ipmi_interfaces_mutex);
3475         /* Look for a hole in the numbers. */
3476         i = 0;
3477         link = &ipmi_interfaces;
3478         list_for_each_entry_rcu(tintf, &ipmi_interfaces, link,
3479                                 ipmi_interfaces_mutex_held()) {
3480                 if (tintf->intf_num != i) {
3481                         link = &tintf->link;
3482                         break;
3483                 }
3484                 i++;
3485         }
3486         /* Add the new interface in numeric order. */
3487         if (i == 0)
3488                 list_add_rcu(&intf->link, &ipmi_interfaces);
3489         else
3490                 list_add_tail_rcu(&intf->link, link);
3491
3492         rv = handlers->start_processing(send_info, intf);
3493         if (rv)
3494                 goto out_err;
3495
3496         rv = __bmc_get_device_id(intf, NULL, &id, NULL, NULL, i);
3497         if (rv) {
3498                 dev_err(si_dev, "Unable to get the device id: %d\n", rv);
3499                 goto out_err_started;
3500         }
3501
3502         mutex_lock(&intf->bmc_reg_mutex);
3503         rv = __scan_channels(intf, &id);
3504         mutex_unlock(&intf->bmc_reg_mutex);
3505         if (rv)
3506                 goto out_err_bmc_reg;
3507
3508         /*
3509          * Keep memory order straight for RCU readers.  Make
3510          * sure everything else is committed to memory before
3511          * setting intf_num to mark the interface valid.
3512          */
3513         smp_wmb();
3514         intf->intf_num = i;
3515         mutex_unlock(&ipmi_interfaces_mutex);
3516
3517         /* After this point the interface is legal to use. */
3518         call_smi_watchers(i, intf->si_dev);
3519
3520         return 0;
3521
3522  out_err_bmc_reg:
3523         ipmi_bmc_unregister(intf);
3524  out_err_started:
3525         if (intf->handlers->shutdown)
3526                 intf->handlers->shutdown(intf->send_info);
3527  out_err:
3528         list_del_rcu(&intf->link);
3529         mutex_unlock(&ipmi_interfaces_mutex);
3530         synchronize_srcu(&ipmi_interfaces_srcu);
3531         cleanup_srcu_struct(&intf->users_srcu);
3532         kref_put(&intf->refcount, intf_free);
3533
3534         return rv;
3535 }
3536 EXPORT_SYMBOL(ipmi_add_smi);
3537
3538 static void deliver_smi_err_response(struct ipmi_smi *intf,
3539                                      struct ipmi_smi_msg *msg,
3540                                      unsigned char err)
3541 {
3542         msg->rsp[0] = msg->data[0] | 4;
3543         msg->rsp[1] = msg->data[1];
3544         msg->rsp[2] = err;
3545         msg->rsp_size = 3;
3546         /* It's an error, so it will never requeue, no need to check return. */
3547         handle_one_recv_msg(intf, msg);
3548 }
3549
3550 static void cleanup_smi_msgs(struct ipmi_smi *intf)
3551 {
3552         int              i;
3553         struct seq_table *ent;
3554         struct ipmi_smi_msg *msg;
3555         struct list_head *entry;
3556         struct list_head tmplist;
3557
3558         /* Clear out our transmit queues and hold the messages. */
3559         INIT_LIST_HEAD(&tmplist);
3560         list_splice_tail(&intf->hp_xmit_msgs, &tmplist);
3561         list_splice_tail(&intf->xmit_msgs, &tmplist);
3562
3563         /* Current message first, to preserve order */
3564         while (intf->curr_msg && !list_empty(&intf->waiting_rcv_msgs)) {
3565                 /* Wait for the message to clear out. */
3566                 schedule_timeout(1);
3567         }
3568
3569         /* No need for locks, the interface is down. */
3570
3571         /*
3572          * Return errors for all pending messages in queue and in the
3573          * tables waiting for remote responses.
3574          */
3575         while (!list_empty(&tmplist)) {
3576                 entry = tmplist.next;
3577                 list_del(entry);
3578                 msg = list_entry(entry, struct ipmi_smi_msg, link);
3579                 deliver_smi_err_response(intf, msg, IPMI_ERR_UNSPECIFIED);
3580         }
3581
3582         for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++) {
3583                 ent = &intf->seq_table[i];
3584                 if (!ent->inuse)
3585                         continue;
3586                 deliver_err_response(intf, ent->recv_msg, IPMI_ERR_UNSPECIFIED);
3587         }
3588 }
3589
3590 void ipmi_unregister_smi(struct ipmi_smi *intf)
3591 {
3592         struct ipmi_smi_watcher *w;
3593         int intf_num = intf->intf_num, index;
3594
3595         mutex_lock(&ipmi_interfaces_mutex);
3596         intf->intf_num = -1;
3597         intf->in_shutdown = true;
3598         list_del_rcu(&intf->link);
3599         mutex_unlock(&ipmi_interfaces_mutex);
3600         synchronize_srcu(&ipmi_interfaces_srcu);
3601
3602         /* At this point no users can be added to the interface. */
3603
3604         /*
3605          * Call all the watcher interfaces to tell them that
3606          * an interface is going away.
3607          */
3608         mutex_lock(&smi_watchers_mutex);
3609         list_for_each_entry(w, &smi_watchers, link)
3610                 w->smi_gone(intf_num);
3611         mutex_unlock(&smi_watchers_mutex);
3612
3613         index = srcu_read_lock(&intf->users_srcu);
3614         while (!list_empty(&intf->users)) {
3615                 struct ipmi_user *user =
3616                         container_of(list_next_rcu(&intf->users),
3617                                      struct ipmi_user, link);
3618
3619                 _ipmi_destroy_user(user);
3620         }
3621         srcu_read_unlock(&intf->users_srcu, index);
3622
3623         if (intf->handlers->shutdown)
3624                 intf->handlers->shutdown(intf->send_info);
3625
3626         cleanup_smi_msgs(intf);
3627
3628         ipmi_bmc_unregister(intf);
3629
3630         cleanup_srcu_struct(&intf->users_srcu);
3631         kref_put(&intf->refcount, intf_free);
3632 }
3633 EXPORT_SYMBOL(ipmi_unregister_smi);
3634
3635 static int handle_ipmb_get_msg_rsp(struct ipmi_smi *intf,
3636                                    struct ipmi_smi_msg *msg)
3637 {
3638         struct ipmi_ipmb_addr ipmb_addr;
3639         struct ipmi_recv_msg  *recv_msg;
3640
3641         /*
3642          * This is 11, not 10, because the response must contain a
3643          * completion code.
3644          */
3645         if (msg->rsp_size < 11) {
3646                 /* Message not big enough, just ignore it. */
3647                 ipmi_inc_stat(intf, invalid_ipmb_responses);
3648                 return 0;
3649         }
3650
3651         if (msg->rsp[2] != 0) {
3652                 /* An error getting the response, just ignore it. */
3653                 return 0;
3654         }
3655
3656         ipmb_addr.addr_type = IPMI_IPMB_ADDR_TYPE;
3657         ipmb_addr.slave_addr = msg->rsp[6];
3658         ipmb_addr.channel = msg->rsp[3] & 0x0f;
3659         ipmb_addr.lun = msg->rsp[7] & 3;
3660
3661         /*
3662          * It's a response from a remote entity.  Look up the sequence
3663          * number and handle the response.
3664          */
3665         if (intf_find_seq(intf,
3666                           msg->rsp[7] >> 2,
3667                           msg->rsp[3] & 0x0f,
3668                           msg->rsp[8],
3669                           (msg->rsp[4] >> 2) & (~1),
3670                           (struct ipmi_addr *) &ipmb_addr,
3671                           &recv_msg)) {
3672                 /*
3673                  * We were unable to find the sequence number,
3674                  * so just nuke the message.
3675                  */
3676                 ipmi_inc_stat(intf, unhandled_ipmb_responses);
3677                 return 0;
3678         }
3679
3680         memcpy(recv_msg->msg_data, &msg->rsp[9], msg->rsp_size - 9);
3681         /*
3682          * The other fields matched, so no need to set them, except
3683          * for netfn, which needs to be the response that was
3684          * returned, not the request value.
3685          */
3686         recv_msg->msg.netfn = msg->rsp[4] >> 2;
3687         recv_msg->msg.data = recv_msg->msg_data;
3688         recv_msg->msg.data_len = msg->rsp_size - 10;
3689         recv_msg->recv_type = IPMI_RESPONSE_RECV_TYPE;
3690         if (deliver_response(intf, recv_msg))
3691                 ipmi_inc_stat(intf, unhandled_ipmb_responses);
3692         else
3693                 ipmi_inc_stat(intf, handled_ipmb_responses);
3694
3695         return 0;
3696 }
3697
3698 static int handle_ipmb_get_msg_cmd(struct ipmi_smi *intf,
3699                                    struct ipmi_smi_msg *msg)
3700 {
3701         struct cmd_rcvr          *rcvr;
3702         int                      rv = 0;
3703         unsigned char            netfn;
3704         unsigned char            cmd;
3705         unsigned char            chan;
3706         struct ipmi_user         *user = NULL;
3707         struct ipmi_ipmb_addr    *ipmb_addr;
3708         struct ipmi_recv_msg     *recv_msg;
3709
3710         if (msg->rsp_size < 10) {
3711                 /* Message not big enough, just ignore it. */
3712                 ipmi_inc_stat(intf, invalid_commands);
3713                 return 0;
3714         }
3715
3716         if (msg->rsp[2] != 0) {
3717                 /* An error getting the response, just ignore it. */
3718                 return 0;
3719         }
3720
3721         netfn = msg->rsp[4] >> 2;
3722         cmd = msg->rsp[8];
3723         chan = msg->rsp[3] & 0xf;
3724
3725         rcu_read_lock();
3726         rcvr = find_cmd_rcvr(intf, netfn, cmd, chan);
3727         if (rcvr) {
3728                 user = rcvr->user;
3729                 kref_get(&user->refcount);
3730         } else
3731                 user = NULL;
3732         rcu_read_unlock();
3733
3734         if (user == NULL) {
3735                 /* We didn't find a user, deliver an error response. */
3736                 ipmi_inc_stat(intf, unhandled_commands);
3737
3738                 msg->data[0] = (IPMI_NETFN_APP_REQUEST << 2);
3739                 msg->data[1] = IPMI_SEND_MSG_CMD;
3740                 msg->data[2] = msg->rsp[3];
3741                 msg->data[3] = msg->rsp[6];
3742                 msg->data[4] = ((netfn + 1) << 2) | (msg->rsp[7] & 0x3);
3743                 msg->data[5] = ipmb_checksum(&msg->data[3], 2);
3744                 msg->data[6] = intf->addrinfo[msg->rsp[3] & 0xf].address;
3745                 /* rqseq/lun */
3746                 msg->data[7] = (msg->rsp[7] & 0xfc) | (msg->rsp[4] & 0x3);
3747                 msg->data[8] = msg->rsp[8]; /* cmd */
3748                 msg->data[9] = IPMI_INVALID_CMD_COMPLETION_CODE;
3749                 msg->data[10] = ipmb_checksum(&msg->data[6], 4);
3750                 msg->data_size = 11;
3751
3752                 pr_debug("Invalid command: %*ph\n", msg->data_size, msg->data);
3753
3754                 rcu_read_lock();
3755                 if (!intf->in_shutdown) {
3756                         smi_send(intf, intf->handlers, msg, 0);
3757                         /*
3758                          * We used the message, so return the value
3759                          * that causes it to not be freed or
3760                          * queued.
3761                          */
3762                         rv = -1;
3763                 }
3764                 rcu_read_unlock();
3765         } else {
3766                 recv_msg = ipmi_alloc_recv_msg();
3767                 if (!recv_msg) {
3768                         /*
3769                          * We couldn't allocate memory for the
3770                          * message, so requeue it for handling
3771                          * later.
3772                          */
3773                         rv = 1;
3774                         kref_put(&user->refcount, free_user);
3775                 } else {
3776                         /* Extract the source address from the data. */
3777                         ipmb_addr = (struct ipmi_ipmb_addr *) &recv_msg->addr;
3778                         ipmb_addr->addr_type = IPMI_IPMB_ADDR_TYPE;
3779                         ipmb_addr->slave_addr = msg->rsp[6];
3780                         ipmb_addr->lun = msg->rsp[7] & 3;
3781                         ipmb_addr->channel = msg->rsp[3] & 0xf;
3782
3783                         /*
3784                          * Extract the rest of the message information
3785                          * from the IPMB header.
3786                          */
3787                         recv_msg->user = user;
3788                         recv_msg->recv_type = IPMI_CMD_RECV_TYPE;
3789                         recv_msg->msgid = msg->rsp[7] >> 2;
3790                         recv_msg->msg.netfn = msg->rsp[4] >> 2;
3791                         recv_msg->msg.cmd = msg->rsp[8];
3792                         recv_msg->msg.data = recv_msg->msg_data;
3793
3794                         /*
3795                          * We chop off 10, not 9 bytes because the checksum
3796                          * at the end also needs to be removed.
3797                          */
3798                         recv_msg->msg.data_len = msg->rsp_size - 10;
3799                         memcpy(recv_msg->msg_data, &msg->rsp[9],
3800                                msg->rsp_size - 10);
3801                         if (deliver_response(intf, recv_msg))
3802                                 ipmi_inc_stat(intf, unhandled_commands);
3803                         else
3804                                 ipmi_inc_stat(intf, handled_commands);
3805                 }
3806         }
3807
3808         return rv;
3809 }
3810
3811 static int handle_lan_get_msg_rsp(struct ipmi_smi *intf,
3812                                   struct ipmi_smi_msg *msg)
3813 {
3814         struct ipmi_lan_addr  lan_addr;
3815         struct ipmi_recv_msg  *recv_msg;
3816
3817
3818         /*
3819          * This is 13, not 12, because the response must contain a
3820          * completion code.
3821          */
3822         if (msg->rsp_size < 13) {
3823                 /* Message not big enough, just ignore it. */
3824                 ipmi_inc_stat(intf, invalid_lan_responses);
3825                 return 0;
3826         }
3827
3828         if (msg->rsp[2] != 0) {
3829                 /* An error getting the response, just ignore it. */
3830                 return 0;
3831         }
3832
3833         lan_addr.addr_type = IPMI_LAN_ADDR_TYPE;
3834         lan_addr.session_handle = msg->rsp[4];
3835         lan_addr.remote_SWID = msg->rsp[8];
3836         lan_addr.local_SWID = msg->rsp[5];
3837         lan_addr.channel = msg->rsp[3] & 0x0f;
3838         lan_addr.privilege = msg->rsp[3] >> 4;
3839         lan_addr.lun = msg->rsp[9] & 3;
3840
3841         /*
3842          * It's a response from a remote entity.  Look up the sequence
3843          * number and handle the response.
3844          */
3845         if (intf_find_seq(intf,
3846                           msg->rsp[9] >> 2,
3847                           msg->rsp[3] & 0x0f,
3848                           msg->rsp[10],
3849                           (msg->rsp[6] >> 2) & (~1),
3850                           (struct ipmi_addr *) &lan_addr,
3851                           &recv_msg)) {
3852                 /*
3853                  * We were unable to find the sequence number,
3854                  * so just nuke the message.
3855                  */
3856                 ipmi_inc_stat(intf, unhandled_lan_responses);
3857                 return 0;
3858         }
3859
3860         memcpy(recv_msg->msg_data, &msg->rsp[11], msg->rsp_size - 11);
3861         /*
3862          * The other fields matched, so no need to set them, except
3863          * for netfn, which needs to be the response that was
3864          * returned, not the request value.
3865          */
3866         recv_msg->msg.netfn = msg->rsp[6] >> 2;
3867         recv_msg->msg.data = recv_msg->msg_data;
3868         recv_msg->msg.data_len = msg->rsp_size - 12;
3869         recv_msg->recv_type = IPMI_RESPONSE_RECV_TYPE;
3870         if (deliver_response(intf, recv_msg))
3871                 ipmi_inc_stat(intf, unhandled_lan_responses);
3872         else
3873                 ipmi_inc_stat(intf, handled_lan_responses);
3874
3875         return 0;
3876 }
3877
3878 static int handle_lan_get_msg_cmd(struct ipmi_smi *intf,
3879                                   struct ipmi_smi_msg *msg)
3880 {
3881         struct cmd_rcvr          *rcvr;
3882         int                      rv = 0;
3883         unsigned char            netfn;
3884         unsigned char            cmd;
3885         unsigned char            chan;
3886         struct ipmi_user         *user = NULL;
3887         struct ipmi_lan_addr     *lan_addr;
3888         struct ipmi_recv_msg     *recv_msg;
3889
3890         if (msg->rsp_size < 12) {
3891                 /* Message not big enough, just ignore it. */
3892                 ipmi_inc_stat(intf, invalid_commands);
3893                 return 0;
3894         }
3895
3896         if (msg->rsp[2] != 0) {
3897                 /* An error getting the response, just ignore it. */
3898                 return 0;
3899         }
3900
3901         netfn = msg->rsp[6] >> 2;
3902         cmd = msg->rsp[10];
3903         chan = msg->rsp[3] & 0xf;
3904
3905         rcu_read_lock();
3906         rcvr = find_cmd_rcvr(intf, netfn, cmd, chan);
3907         if (rcvr) {
3908                 user = rcvr->user;
3909                 kref_get(&user->refcount);
3910         } else
3911                 user = NULL;
3912         rcu_read_unlock();
3913
3914         if (user == NULL) {
3915                 /* We didn't find a user, just give up. */
3916                 ipmi_inc_stat(intf, unhandled_commands);
3917
3918                 /*
3919                  * Don't do anything with these messages, just allow
3920                  * them to be freed.
3921                  */
3922                 rv = 0;
3923         } else {
3924                 recv_msg = ipmi_alloc_recv_msg();
3925                 if (!recv_msg) {
3926                         /*
3927                          * We couldn't allocate memory for the
3928                          * message, so requeue it for handling later.
3929                          */
3930                         rv = 1;
3931                         kref_put(&user->refcount, free_user);
3932                 } else {
3933                         /* Extract the source address from the data. */
3934                         lan_addr = (struct ipmi_lan_addr *) &recv_msg->addr;
3935                         lan_addr->addr_type = IPMI_LAN_ADDR_TYPE;
3936                         lan_addr->session_handle = msg->rsp[4];
3937                         lan_addr->remote_SWID = msg->rsp[8];
3938                         lan_addr->local_SWID = msg->rsp[5];
3939                         lan_addr->lun = msg->rsp[9] & 3;
3940                         lan_addr->channel = msg->rsp[3] & 0xf;
3941                         lan_addr->privilege = msg->rsp[3] >> 4;
3942
3943                         /*
3944                          * Extract the rest of the message information
3945                          * from the IPMB header.
3946                          */
3947                         recv_msg->user = user;
3948                         recv_msg->recv_type = IPMI_CMD_RECV_TYPE;
3949                         recv_msg->msgid = msg->rsp[9] >> 2;
3950                         recv_msg->msg.netfn = msg->rsp[6] >> 2;
3951                         recv_msg->msg.cmd = msg->rsp[10];
3952                         recv_msg->msg.data = recv_msg->msg_data;
3953
3954                         /*
3955                          * We chop off 12, not 11 bytes because the checksum
3956                          * at the end also needs to be removed.
3957                          */
3958                         recv_msg->msg.data_len = msg->rsp_size - 12;
3959                         memcpy(recv_msg->msg_data, &msg->rsp[11],
3960                                msg->rsp_size - 12);
3961                         if (deliver_response(intf, recv_msg))
3962                                 ipmi_inc_stat(intf, unhandled_commands);
3963                         else
3964                                 ipmi_inc_stat(intf, handled_commands);
3965                 }
3966         }
3967
3968         return rv;
3969 }
3970
3971 /*
3972  * This routine will handle "Get Message" command responses with
3973  * channels that use an OEM Medium. The message format belongs to
3974  * the OEM.  See IPMI 2.0 specification, Chapter 6 and
3975  * Chapter 22, sections 22.6 and 22.24 for more details.
3976  */
3977 static int handle_oem_get_msg_cmd(struct ipmi_smi *intf,
3978                                   struct ipmi_smi_msg *msg)
3979 {
3980         struct cmd_rcvr       *rcvr;
3981         int                   rv = 0;
3982         unsigned char         netfn;
3983         unsigned char         cmd;
3984         unsigned char         chan;
3985         struct ipmi_user *user = NULL;
3986         struct ipmi_system_interface_addr *smi_addr;
3987         struct ipmi_recv_msg  *recv_msg;
3988
3989         /*
3990          * We expect the OEM SW to perform error checking
3991          * so we just do some basic sanity checks
3992          */
3993         if (msg->rsp_size < 4) {
3994                 /* Message not big enough, just ignore it. */
3995                 ipmi_inc_stat(intf, invalid_commands);
3996                 return 0;
3997         }
3998
3999         if (msg->rsp[2] != 0) {
4000                 /* An error getting the response, just ignore it. */
4001                 return 0;
4002         }
4003
4004         /*
4005          * This is an OEM Message so the OEM needs to know how
4006          * handle the message. We do no interpretation.
4007          */
4008         netfn = msg->rsp[0] >> 2;
4009         cmd = msg->rsp[1];
4010         chan = msg->rsp[3] & 0xf;
4011
4012         rcu_read_lock();
4013         rcvr = find_cmd_rcvr(intf, netfn, cmd, chan);
4014         if (rcvr) {
4015                 user = rcvr->user;
4016                 kref_get(&user->refcount);
4017         } else
4018                 user = NULL;
4019         rcu_read_unlock();
4020
4021         if (user == NULL) {
4022                 /* We didn't find a user, just give up. */
4023                 ipmi_inc_stat(intf, unhandled_commands);
4024
4025                 /*
4026                  * Don't do anything with these messages, just allow
4027                  * them to be freed.
4028                  */
4029
4030                 rv = 0;
4031         } else {
4032                 recv_msg = ipmi_alloc_recv_msg();
4033                 if (!recv_msg) {
4034                         /*
4035                          * We couldn't allocate memory for the
4036                          * message, so requeue it for handling
4037                          * later.
4038                          */
4039                         rv = 1;
4040                         kref_put(&user->refcount, free_user);
4041                 } else {
4042                         /*
4043                          * OEM Messages are expected to be delivered via
4044                          * the system interface to SMS software.  We might
4045                          * need to visit this again depending on OEM
4046                          * requirements
4047                          */
4048                         smi_addr = ((struct ipmi_system_interface_addr *)
4049                                     &recv_msg->addr);
4050                         smi_addr->addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
4051                         smi_addr->channel = IPMI_BMC_CHANNEL;
4052                         smi_addr->lun = msg->rsp[0] & 3;
4053
4054                         recv_msg->user = user;
4055                         recv_msg->user_msg_data = NULL;
4056                         recv_msg->recv_type = IPMI_OEM_RECV_TYPE;
4057                         recv_msg->msg.netfn = msg->rsp[0] >> 2;
4058                         recv_msg->msg.cmd = msg->rsp[1];
4059                         recv_msg->msg.data = recv_msg->msg_data;
4060
4061                         /*
4062                          * The message starts at byte 4 which follows the
4063                          * the Channel Byte in the "GET MESSAGE" command
4064                          */
4065                         recv_msg->msg.data_len = msg->rsp_size - 4;
4066                         memcpy(recv_msg->msg_data, &msg->rsp[4],
4067                                msg->rsp_size - 4);
4068                         if (deliver_response(intf, recv_msg))
4069                                 ipmi_inc_stat(intf, unhandled_commands);
4070                         else
4071                                 ipmi_inc_stat(intf, handled_commands);
4072                 }
4073         }
4074
4075         return rv;
4076 }
4077
4078 static void copy_event_into_recv_msg(struct ipmi_recv_msg *recv_msg,
4079                                      struct ipmi_smi_msg  *msg)
4080 {
4081         struct ipmi_system_interface_addr *smi_addr;
4082
4083         recv_msg->msgid = 0;
4084         smi_addr = (struct ipmi_system_interface_addr *) &recv_msg->addr;
4085         smi_addr->addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
4086         smi_addr->channel = IPMI_BMC_CHANNEL;
4087         smi_addr->lun = msg->rsp[0] & 3;
4088         recv_msg->recv_type = IPMI_ASYNC_EVENT_RECV_TYPE;
4089         recv_msg->msg.netfn = msg->rsp[0] >> 2;
4090         recv_msg->msg.cmd = msg->rsp[1];
4091         memcpy(recv_msg->msg_data, &msg->rsp[3], msg->rsp_size - 3);
4092         recv_msg->msg.data = recv_msg->msg_data;
4093         recv_msg->msg.data_len = msg->rsp_size - 3;
4094 }
4095
4096 static int handle_read_event_rsp(struct ipmi_smi *intf,
4097                                  struct ipmi_smi_msg *msg)
4098 {
4099         struct ipmi_recv_msg *recv_msg, *recv_msg2;
4100         struct list_head     msgs;
4101         struct ipmi_user     *user;
4102         int rv = 0, deliver_count = 0, index;
4103         unsigned long        flags;
4104
4105         if (msg->rsp_size < 19) {
4106                 /* Message is too small to be an IPMB event. */
4107                 ipmi_inc_stat(intf, invalid_events);
4108                 return 0;
4109         }
4110
4111         if (msg->rsp[2] != 0) {
4112                 /* An error getting the event, just ignore it. */
4113                 return 0;
4114         }
4115
4116         INIT_LIST_HEAD(&msgs);
4117
4118         spin_lock_irqsave(&intf->events_lock, flags);
4119
4120         ipmi_inc_stat(intf, events);
4121
4122         /*
4123          * Allocate and fill in one message for every user that is
4124          * getting events.
4125          */
4126         index = srcu_read_lock(&intf->users_srcu);
4127         list_for_each_entry_rcu(user, &intf->users, link) {
4128                 if (!user->gets_events)
4129                         continue;
4130
4131                 recv_msg = ipmi_alloc_recv_msg();
4132                 if (!recv_msg) {
4133                         rcu_read_unlock();
4134                         list_for_each_entry_safe(recv_msg, recv_msg2, &msgs,
4135                                                  link) {
4136                                 list_del(&recv_msg->link);
4137                                 ipmi_free_recv_msg(recv_msg);
4138                         }
4139                         /*
4140                          * We couldn't allocate memory for the
4141                          * message, so requeue it for handling
4142                          * later.
4143                          */
4144                         rv = 1;
4145                         goto out;
4146                 }
4147
4148                 deliver_count++;
4149
4150                 copy_event_into_recv_msg(recv_msg, msg);
4151                 recv_msg->user = user;
4152                 kref_get(&user->refcount);
4153                 list_add_tail(&recv_msg->link, &msgs);
4154         }
4155         srcu_read_unlock(&intf->users_srcu, index);
4156
4157         if (deliver_count) {
4158                 /* Now deliver all the messages. */
4159                 list_for_each_entry_safe(recv_msg, recv_msg2, &msgs, link) {
4160                         list_del(&recv_msg->link);
4161                         deliver_local_response(intf, recv_msg);
4162                 }
4163         } else if (intf->waiting_events_count < MAX_EVENTS_IN_QUEUE) {
4164                 /*
4165                  * No one to receive the message, put it in queue if there's
4166                  * not already too many things in the queue.
4167                  */
4168                 recv_msg = ipmi_alloc_recv_msg();
4169                 if (!recv_msg) {
4170                         /*
4171                          * We couldn't allocate memory for the
4172                          * message, so requeue it for handling
4173                          * later.
4174                          */
4175                         rv = 1;
4176                         goto out;
4177                 }
4178
4179                 copy_event_into_recv_msg(recv_msg, msg);
4180                 list_add_tail(&recv_msg->link, &intf->waiting_events);
4181                 intf->waiting_events_count++;
4182         } else if (!intf->event_msg_printed) {
4183                 /*
4184                  * There's too many things in the queue, discard this
4185                  * message.
4186                  */
4187                 dev_warn(intf->si_dev,
4188                          "Event queue full, discarding incoming events\n");
4189                 intf->event_msg_printed = 1;
4190         }
4191
4192  out:
4193         spin_unlock_irqrestore(&intf->events_lock, flags);
4194
4195         return rv;
4196 }
4197
4198 static int handle_bmc_rsp(struct ipmi_smi *intf,
4199                           struct ipmi_smi_msg *msg)
4200 {
4201         struct ipmi_recv_msg *recv_msg;
4202         struct ipmi_system_interface_addr *smi_addr;
4203
4204         recv_msg = (struct ipmi_recv_msg *) msg->user_data;
4205         if (recv_msg == NULL) {
4206                 dev_warn(intf->si_dev,
4207                          "IPMI message received with no owner. This could be because of a malformed message, or because of a hardware error.  Contact your hardware vendor for assistance.\n");
4208                 return 0;
4209         }
4210
4211         recv_msg->recv_type = IPMI_RESPONSE_RECV_TYPE;
4212         recv_msg->msgid = msg->msgid;
4213         smi_addr = ((struct ipmi_system_interface_addr *)
4214                     &recv_msg->addr);
4215         smi_addr->addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
4216         smi_addr->channel = IPMI_BMC_CHANNEL;
4217         smi_addr->lun = msg->rsp[0] & 3;
4218         recv_msg->msg.netfn = msg->rsp[0] >> 2;
4219         recv_msg->msg.cmd = msg->rsp[1];
4220         memcpy(recv_msg->msg_data, &msg->rsp[2], msg->rsp_size - 2);
4221         recv_msg->msg.data = recv_msg->msg_data;
4222         recv_msg->msg.data_len = msg->rsp_size - 2;
4223         deliver_local_response(intf, recv_msg);
4224
4225         return 0;
4226 }
4227
4228 /*
4229  * Handle a received message.  Return 1 if the message should be requeued,
4230  * 0 if the message should be freed, or -1 if the message should not
4231  * be freed or requeued.
4232  */
4233 static int handle_one_recv_msg(struct ipmi_smi *intf,
4234                                struct ipmi_smi_msg *msg)
4235 {
4236         int requeue;
4237         int chan;
4238
4239         pr_debug("Recv: %*ph\n", msg->rsp_size, msg->rsp);
4240
4241         if ((msg->data_size >= 2)
4242             && (msg->data[0] == (IPMI_NETFN_APP_REQUEST << 2))
4243             && (msg->data[1] == IPMI_SEND_MSG_CMD)
4244             && (msg->user_data == NULL)) {
4245
4246                 if (intf->in_shutdown)
4247                         goto free_msg;
4248
4249                 /*
4250                  * This is the local response to a command send, start
4251                  * the timer for these.  The user_data will not be
4252                  * NULL if this is a response send, and we will let
4253                  * response sends just go through.
4254                  */
4255
4256                 /*
4257                  * Check for errors, if we get certain errors (ones
4258                  * that mean basically we can try again later), we
4259                  * ignore them and start the timer.  Otherwise we
4260                  * report the error immediately.
4261                  */
4262                 if ((msg->rsp_size >= 3) && (msg->rsp[2] != 0)
4263                     && (msg->rsp[2] != IPMI_NODE_BUSY_ERR)
4264                     && (msg->rsp[2] != IPMI_LOST_ARBITRATION_ERR)
4265                     && (msg->rsp[2] != IPMI_BUS_ERR)
4266                     && (msg->rsp[2] != IPMI_NAK_ON_WRITE_ERR)) {
4267                         int ch = msg->rsp[3] & 0xf;
4268                         struct ipmi_channel *chans;
4269
4270                         /* Got an error sending the message, handle it. */
4271
4272                         chans = READ_ONCE(intf->channel_list)->c;
4273                         if ((chans[ch].medium == IPMI_CHANNEL_MEDIUM_8023LAN)
4274                             || (chans[ch].medium == IPMI_CHANNEL_MEDIUM_ASYNC))
4275                                 ipmi_inc_stat(intf, sent_lan_command_errs);
4276                         else
4277                                 ipmi_inc_stat(intf, sent_ipmb_command_errs);
4278                         intf_err_seq(intf, msg->msgid, msg->rsp[2]);
4279                 } else
4280                         /* The message was sent, start the timer. */
4281                         intf_start_seq_timer(intf, msg->msgid);
4282 free_msg:
4283                 requeue = 0;
4284                 goto out;
4285
4286         } else if (msg->rsp_size < 2) {
4287                 /* Message is too small to be correct. */
4288                 dev_warn(intf->si_dev,
4289                          "BMC returned too small a message for netfn %x cmd %x, got %d bytes\n",
4290                          (msg->data[0] >> 2) | 1, msg->data[1], msg->rsp_size);
4291
4292                 /* Generate an error response for the message. */
4293                 msg->rsp[0] = msg->data[0] | (1 << 2);
4294                 msg->rsp[1] = msg->data[1];
4295                 msg->rsp[2] = IPMI_ERR_UNSPECIFIED;
4296                 msg->rsp_size = 3;
4297         } else if (((msg->rsp[0] >> 2) != ((msg->data[0] >> 2) | 1))
4298                    || (msg->rsp[1] != msg->data[1])) {
4299                 /*
4300                  * The NetFN and Command in the response is not even
4301                  * marginally correct.
4302                  */
4303                 dev_warn(intf->si_dev,
4304                          "BMC returned incorrect response, expected netfn %x cmd %x, got netfn %x cmd %x\n",
4305                          (msg->data[0] >> 2) | 1, msg->data[1],
4306                          msg->rsp[0] >> 2, msg->rsp[1]);
4307
4308                 /* Generate an error response for the message. */
4309                 msg->rsp[0] = msg->data[0] | (1 << 2);
4310                 msg->rsp[1] = msg->data[1];
4311                 msg->rsp[2] = IPMI_ERR_UNSPECIFIED;
4312                 msg->rsp_size = 3;
4313         }
4314
4315         if ((msg->rsp[0] == ((IPMI_NETFN_APP_REQUEST|1) << 2))
4316             && (msg->rsp[1] == IPMI_SEND_MSG_CMD)
4317             && (msg->user_data != NULL)) {
4318                 /*
4319                  * It's a response to a response we sent.  For this we
4320                  * deliver a send message response to the user.
4321                  */
4322                 struct ipmi_recv_msg *recv_msg = msg->user_data;
4323
4324                 requeue = 0;
4325                 if (msg->rsp_size < 2)
4326                         /* Message is too small to be correct. */
4327                         goto out;
4328
4329                 chan = msg->data[2] & 0x0f;
4330                 if (chan >= IPMI_MAX_CHANNELS)
4331                         /* Invalid channel number */
4332                         goto out;
4333
4334                 if (!recv_msg)
4335                         goto out;
4336
4337                 recv_msg->recv_type = IPMI_RESPONSE_RESPONSE_TYPE;
4338                 recv_msg->msg.data = recv_msg->msg_data;
4339                 recv_msg->msg.data_len = 1;
4340                 recv_msg->msg_data[0] = msg->rsp[2];
4341                 deliver_local_response(intf, recv_msg);
4342         } else if ((msg->rsp[0] == ((IPMI_NETFN_APP_REQUEST|1) << 2))
4343                    && (msg->rsp[1] == IPMI_GET_MSG_CMD)) {
4344                 struct ipmi_channel   *chans;
4345
4346                 /* It's from the receive queue. */
4347                 chan = msg->rsp[3] & 0xf;
4348                 if (chan >= IPMI_MAX_CHANNELS) {
4349                         /* Invalid channel number */
4350                         requeue = 0;
4351                         goto out;
4352                 }
4353
4354                 /*
4355                  * We need to make sure the channels have been initialized.
4356                  * The channel_handler routine will set the "curr_channel"
4357                  * equal to or greater than IPMI_MAX_CHANNELS when all the
4358                  * channels for this interface have been initialized.
4359                  */
4360                 if (!intf->channels_ready) {
4361                         requeue = 0; /* Throw the message away */
4362                         goto out;
4363                 }
4364
4365                 chans = READ_ONCE(intf->channel_list)->c;
4366
4367                 switch (chans[chan].medium) {
4368                 case IPMI_CHANNEL_MEDIUM_IPMB:
4369                         if (msg->rsp[4] & 0x04) {
4370                                 /*
4371                                  * It's a response, so find the
4372                                  * requesting message and send it up.
4373                                  */
4374                                 requeue = handle_ipmb_get_msg_rsp(intf, msg);
4375                         } else {
4376                                 /*
4377                                  * It's a command to the SMS from some other
4378                                  * entity.  Handle that.
4379                                  */
4380                                 requeue = handle_ipmb_get_msg_cmd(intf, msg);
4381                         }
4382                         break;
4383
4384                 case IPMI_CHANNEL_MEDIUM_8023LAN:
4385                 case IPMI_CHANNEL_MEDIUM_ASYNC:
4386                         if (msg->rsp[6] & 0x04) {
4387                                 /*
4388                                  * It's a response, so find the
4389                                  * requesting message and send it up.
4390                                  */
4391                                 requeue = handle_lan_get_msg_rsp(intf, msg);
4392                         } else {
4393                                 /*
4394                                  * It's a command to the SMS from some other
4395                                  * entity.  Handle that.
4396                                  */
4397                                 requeue = handle_lan_get_msg_cmd(intf, msg);
4398                         }
4399                         break;
4400
4401                 default:
4402                         /* Check for OEM Channels.  Clients had better
4403                            register for these commands. */
4404                         if ((chans[chan].medium >= IPMI_CHANNEL_MEDIUM_OEM_MIN)
4405                             && (chans[chan].medium
4406                                 <= IPMI_CHANNEL_MEDIUM_OEM_MAX)) {
4407                                 requeue = handle_oem_get_msg_cmd(intf, msg);
4408                         } else {
4409                                 /*
4410                                  * We don't handle the channel type, so just
4411                                  * free the message.
4412                                  */
4413                                 requeue = 0;
4414                         }
4415                 }
4416
4417         } else if ((msg->rsp[0] == ((IPMI_NETFN_APP_REQUEST|1) << 2))
4418                    && (msg->rsp[1] == IPMI_READ_EVENT_MSG_BUFFER_CMD)) {
4419                 /* It's an asynchronous event. */
4420                 requeue = handle_read_event_rsp(intf, msg);
4421         } else {
4422                 /* It's a response from the local BMC. */
4423                 requeue = handle_bmc_rsp(intf, msg);
4424         }
4425
4426  out:
4427         return requeue;
4428 }
4429
4430 /*
4431  * If there are messages in the queue or pretimeouts, handle them.
4432  */
4433 static void handle_new_recv_msgs(struct ipmi_smi *intf)
4434 {
4435         struct ipmi_smi_msg  *smi_msg;
4436         unsigned long        flags = 0;
4437         int                  rv;
4438         int                  run_to_completion = intf->run_to_completion;
4439
4440         /* See if any waiting messages need to be processed. */
4441         if (!run_to_completion)
4442                 spin_lock_irqsave(&intf->waiting_rcv_msgs_lock, flags);
4443         while (!list_empty(&intf->waiting_rcv_msgs)) {
4444                 smi_msg = list_entry(intf->waiting_rcv_msgs.next,
4445                                      struct ipmi_smi_msg, link);
4446                 list_del(&smi_msg->link);
4447                 if (!run_to_completion)
4448                         spin_unlock_irqrestore(&intf->waiting_rcv_msgs_lock,
4449                                                flags);
4450                 rv = handle_one_recv_msg(intf, smi_msg);
4451                 if (!run_to_completion)
4452                         spin_lock_irqsave(&intf->waiting_rcv_msgs_lock, flags);
4453                 if (rv > 0) {
4454                         /*
4455                          * To preserve message order, quit if we
4456                          * can't handle a message.  Add the message
4457                          * back at the head, this is safe because this
4458                          * tasklet is the only thing that pulls the
4459                          * messages.
4460                          */
4461                         list_add(&smi_msg->link, &intf->waiting_rcv_msgs);
4462                         break;
4463                 } else {
4464                         if (rv == 0)
4465                                 /* Message handled */
4466                                 ipmi_free_smi_msg(smi_msg);
4467                         /* If rv < 0, fatal error, del but don't free. */
4468                 }
4469         }
4470         if (!run_to_completion)
4471                 spin_unlock_irqrestore(&intf->waiting_rcv_msgs_lock, flags);
4472
4473         /*
4474          * If the pretimout count is non-zero, decrement one from it and
4475          * deliver pretimeouts to all the users.
4476          */
4477         if (atomic_add_unless(&intf->watchdog_pretimeouts_to_deliver, -1, 0)) {
4478                 struct ipmi_user *user;
4479                 int index;
4480
4481                 index = srcu_read_lock(&intf->users_srcu);
4482                 list_for_each_entry_rcu(user, &intf->users, link) {
4483                         if (user->handler->ipmi_watchdog_pretimeout)
4484                                 user->handler->ipmi_watchdog_pretimeout(
4485                                         user->handler_data);
4486                 }
4487                 srcu_read_unlock(&intf->users_srcu, index);
4488         }
4489 }
4490
4491 static void smi_recv_tasklet(struct tasklet_struct *t)
4492 {
4493         unsigned long flags = 0; /* keep us warning-free. */
4494         struct ipmi_smi *intf = from_tasklet(intf, t, recv_tasklet);
4495         int run_to_completion = intf->run_to_completion;
4496         struct ipmi_smi_msg *newmsg = NULL;
4497
4498         /*
4499          * Start the next message if available.
4500          *
4501          * Do this here, not in the actual receiver, because we may deadlock
4502          * because the lower layer is allowed to hold locks while calling
4503          * message delivery.
4504          */
4505
4506         rcu_read_lock();
4507
4508         if (!run_to_completion)
4509                 spin_lock_irqsave(&intf->xmit_msgs_lock, flags);
4510         if (intf->curr_msg == NULL && !intf->in_shutdown) {
4511                 struct list_head *entry = NULL;
4512
4513                 /* Pick the high priority queue first. */
4514                 if (!list_empty(&intf->hp_xmit_msgs))
4515                         entry = intf->hp_xmit_msgs.next;
4516                 else if (!list_empty(&intf->xmit_msgs))
4517                         entry = intf->xmit_msgs.next;
4518
4519                 if (entry) {
4520                         list_del(entry);
4521                         newmsg = list_entry(entry, struct ipmi_smi_msg, link);
4522                         intf->curr_msg = newmsg;
4523                 }
4524         }
4525
4526         if (!run_to_completion)
4527                 spin_unlock_irqrestore(&intf->xmit_msgs_lock, flags);
4528         if (newmsg)
4529                 intf->handlers->sender(intf->send_info, newmsg);
4530
4531         rcu_read_unlock();
4532
4533         handle_new_recv_msgs(intf);
4534 }
4535
4536 /* Handle a new message from the lower layer. */
4537 void ipmi_smi_msg_received(struct ipmi_smi *intf,
4538                            struct ipmi_smi_msg *msg)
4539 {
4540         unsigned long flags = 0; /* keep us warning-free. */
4541         int run_to_completion = intf->run_to_completion;
4542
4543         /*
4544          * To preserve message order, we keep a queue and deliver from
4545          * a tasklet.
4546          */
4547         if (!run_to_completion)
4548                 spin_lock_irqsave(&intf->waiting_rcv_msgs_lock, flags);
4549         list_add_tail(&msg->link, &intf->waiting_rcv_msgs);
4550         if (!run_to_completion)
4551                 spin_unlock_irqrestore(&intf->waiting_rcv_msgs_lock,
4552                                        flags);
4553
4554         if (!run_to_completion)
4555                 spin_lock_irqsave(&intf->xmit_msgs_lock, flags);
4556         /*
4557          * We can get an asynchronous event or receive message in addition
4558          * to commands we send.
4559          */
4560         if (msg == intf->curr_msg)
4561                 intf->curr_msg = NULL;
4562         if (!run_to_completion)
4563                 spin_unlock_irqrestore(&intf->xmit_msgs_lock, flags);
4564
4565         if (run_to_completion)
4566                 smi_recv_tasklet(&intf->recv_tasklet);
4567         else
4568                 tasklet_schedule(&intf->recv_tasklet);
4569 }
4570 EXPORT_SYMBOL(ipmi_smi_msg_received);
4571
4572 void ipmi_smi_watchdog_pretimeout(struct ipmi_smi *intf)
4573 {
4574         if (intf->in_shutdown)
4575                 return;
4576
4577         atomic_set(&intf->watchdog_pretimeouts_to_deliver, 1);
4578         tasklet_schedule(&intf->recv_tasklet);
4579 }
4580 EXPORT_SYMBOL(ipmi_smi_watchdog_pretimeout);
4581
4582 static struct ipmi_smi_msg *
4583 smi_from_recv_msg(struct ipmi_smi *intf, struct ipmi_recv_msg *recv_msg,
4584                   unsigned char seq, long seqid)
4585 {
4586         struct ipmi_smi_msg *smi_msg = ipmi_alloc_smi_msg();
4587         if (!smi_msg)
4588                 /*
4589                  * If we can't allocate the message, then just return, we
4590                  * get 4 retries, so this should be ok.
4591                  */
4592                 return NULL;
4593
4594         memcpy(smi_msg->data, recv_msg->msg.data, recv_msg->msg.data_len);
4595         smi_msg->data_size = recv_msg->msg.data_len;
4596         smi_msg->msgid = STORE_SEQ_IN_MSGID(seq, seqid);
4597
4598         pr_debug("Resend: %*ph\n", smi_msg->data_size, smi_msg->data);
4599
4600         return smi_msg;
4601 }
4602
4603 static void check_msg_timeout(struct ipmi_smi *intf, struct seq_table *ent,
4604                               struct list_head *timeouts,
4605                               unsigned long timeout_period,
4606                               int slot, unsigned long *flags,
4607                               bool *need_timer)
4608 {
4609         struct ipmi_recv_msg *msg;
4610
4611         if (intf->in_shutdown)
4612                 return;
4613
4614         if (!ent->inuse)
4615                 return;
4616
4617         if (timeout_period < ent->timeout) {
4618                 ent->timeout -= timeout_period;
4619                 *need_timer = true;
4620                 return;
4621         }
4622
4623         if (ent->retries_left == 0) {
4624                 /* The message has used all its retries. */
4625                 ent->inuse = 0;
4626                 smi_remove_watch(intf, IPMI_WATCH_MASK_CHECK_MESSAGES);
4627                 msg = ent->recv_msg;
4628                 list_add_tail(&msg->link, timeouts);
4629                 if (ent->broadcast)
4630                         ipmi_inc_stat(intf, timed_out_ipmb_broadcasts);
4631                 else if (is_lan_addr(&ent->recv_msg->addr))
4632                         ipmi_inc_stat(intf, timed_out_lan_commands);
4633                 else
4634                         ipmi_inc_stat(intf, timed_out_ipmb_commands);
4635         } else {
4636                 struct ipmi_smi_msg *smi_msg;
4637                 /* More retries, send again. */
4638
4639                 *need_timer = true;
4640
4641                 /*
4642                  * Start with the max timer, set to normal timer after
4643                  * the message is sent.
4644                  */
4645                 ent->timeout = MAX_MSG_TIMEOUT;
4646                 ent->retries_left--;
4647                 smi_msg = smi_from_recv_msg(intf, ent->recv_msg, slot,
4648                                             ent->seqid);
4649                 if (!smi_msg) {
4650                         if (is_lan_addr(&ent->recv_msg->addr))
4651                                 ipmi_inc_stat(intf,
4652                                               dropped_rexmit_lan_commands);
4653                         else
4654                                 ipmi_inc_stat(intf,
4655                                               dropped_rexmit_ipmb_commands);
4656                         return;
4657                 }
4658
4659                 spin_unlock_irqrestore(&intf->seq_lock, *flags);
4660
4661                 /*
4662                  * Send the new message.  We send with a zero
4663                  * priority.  It timed out, I doubt time is that
4664                  * critical now, and high priority messages are really
4665                  * only for messages to the local MC, which don't get
4666                  * resent.
4667                  */
4668                 if (intf->handlers) {
4669                         if (is_lan_addr(&ent->recv_msg->addr))
4670                                 ipmi_inc_stat(intf,
4671                                               retransmitted_lan_commands);
4672                         else
4673                                 ipmi_inc_stat(intf,
4674                                               retransmitted_ipmb_commands);
4675
4676                         smi_send(intf, intf->handlers, smi_msg, 0);
4677                 } else
4678                         ipmi_free_smi_msg(smi_msg);
4679
4680                 spin_lock_irqsave(&intf->seq_lock, *flags);
4681         }
4682 }
4683
4684 static bool ipmi_timeout_handler(struct ipmi_smi *intf,
4685                                  unsigned long timeout_period)
4686 {
4687         struct list_head     timeouts;
4688         struct ipmi_recv_msg *msg, *msg2;
4689         unsigned long        flags;
4690         int                  i;
4691         bool                 need_timer = false;
4692
4693         if (!intf->bmc_registered) {
4694                 kref_get(&intf->refcount);
4695                 if (!schedule_work(&intf->bmc_reg_work)) {
4696                         kref_put(&intf->refcount, intf_free);
4697                         need_timer = true;
4698                 }
4699         }
4700
4701         /*
4702          * Go through the seq table and find any messages that
4703          * have timed out, putting them in the timeouts
4704          * list.
4705          */
4706         INIT_LIST_HEAD(&timeouts);
4707         spin_lock_irqsave(&intf->seq_lock, flags);
4708         if (intf->ipmb_maintenance_mode_timeout) {
4709                 if (intf->ipmb_maintenance_mode_timeout <= timeout_period)
4710                         intf->ipmb_maintenance_mode_timeout = 0;
4711                 else
4712                         intf->ipmb_maintenance_mode_timeout -= timeout_period;
4713         }
4714         for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++)
4715                 check_msg_timeout(intf, &intf->seq_table[i],
4716                                   &timeouts, timeout_period, i,
4717                                   &flags, &need_timer);
4718         spin_unlock_irqrestore(&intf->seq_lock, flags);
4719
4720         list_for_each_entry_safe(msg, msg2, &timeouts, link)
4721                 deliver_err_response(intf, msg, IPMI_TIMEOUT_COMPLETION_CODE);
4722
4723         /*
4724          * Maintenance mode handling.  Check the timeout
4725          * optimistically before we claim the lock.  It may
4726          * mean a timeout gets missed occasionally, but that
4727          * only means the timeout gets extended by one period
4728          * in that case.  No big deal, and it avoids the lock
4729          * most of the time.
4730          */
4731         if (intf->auto_maintenance_timeout > 0) {
4732                 spin_lock_irqsave(&intf->maintenance_mode_lock, flags);
4733                 if (intf->auto_maintenance_timeout > 0) {
4734                         intf->auto_maintenance_timeout
4735                                 -= timeout_period;
4736                         if (!intf->maintenance_mode
4737                             && (intf->auto_maintenance_timeout <= 0)) {
4738                                 intf->maintenance_mode_enable = false;
4739                                 maintenance_mode_update(intf);
4740                         }
4741                 }
4742                 spin_unlock_irqrestore(&intf->maintenance_mode_lock,
4743                                        flags);
4744         }
4745
4746         tasklet_schedule(&intf->recv_tasklet);
4747
4748         return need_timer;
4749 }
4750
4751 static void ipmi_request_event(struct ipmi_smi *intf)
4752 {
4753         /* No event requests when in maintenance mode. */
4754         if (intf->maintenance_mode_enable)
4755                 return;
4756
4757         if (!intf->in_shutdown)
4758                 intf->handlers->request_events(intf->send_info);
4759 }
4760
4761 static struct timer_list ipmi_timer;
4762
4763 static atomic_t stop_operation;
4764
4765 static void ipmi_timeout(struct timer_list *unused)
4766 {
4767         struct ipmi_smi *intf;
4768         bool need_timer = false;
4769         int index;
4770
4771         if (atomic_read(&stop_operation))
4772                 return;
4773
4774         index = srcu_read_lock(&ipmi_interfaces_srcu);
4775         list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
4776                 if (atomic_read(&intf->event_waiters)) {
4777                         intf->ticks_to_req_ev--;
4778                         if (intf->ticks_to_req_ev == 0) {
4779                                 ipmi_request_event(intf);
4780                                 intf->ticks_to_req_ev = IPMI_REQUEST_EV_TIME;
4781                         }
4782                         need_timer = true;
4783                 }
4784
4785                 need_timer |= ipmi_timeout_handler(intf, IPMI_TIMEOUT_TIME);
4786         }
4787         srcu_read_unlock(&ipmi_interfaces_srcu, index);
4788
4789         if (need_timer)
4790                 mod_timer(&ipmi_timer, jiffies + IPMI_TIMEOUT_JIFFIES);
4791 }
4792
4793 static void need_waiter(struct ipmi_smi *intf)
4794 {
4795         /* Racy, but worst case we start the timer twice. */
4796         if (!timer_pending(&ipmi_timer))
4797                 mod_timer(&ipmi_timer, jiffies + IPMI_TIMEOUT_JIFFIES);
4798 }
4799
4800 static atomic_t smi_msg_inuse_count = ATOMIC_INIT(0);
4801 static atomic_t recv_msg_inuse_count = ATOMIC_INIT(0);
4802
4803 static void free_smi_msg(struct ipmi_smi_msg *msg)
4804 {
4805         atomic_dec(&smi_msg_inuse_count);
4806         kfree(msg);
4807 }
4808
4809 struct ipmi_smi_msg *ipmi_alloc_smi_msg(void)
4810 {
4811         struct ipmi_smi_msg *rv;
4812         rv = kmalloc(sizeof(struct ipmi_smi_msg), GFP_ATOMIC);
4813         if (rv) {
4814                 rv->done = free_smi_msg;
4815                 rv->user_data = NULL;
4816                 atomic_inc(&smi_msg_inuse_count);
4817         }
4818         return rv;
4819 }
4820 EXPORT_SYMBOL(ipmi_alloc_smi_msg);
4821
4822 static void free_recv_msg(struct ipmi_recv_msg *msg)
4823 {
4824         atomic_dec(&recv_msg_inuse_count);
4825         kfree(msg);
4826 }
4827
4828 static struct ipmi_recv_msg *ipmi_alloc_recv_msg(void)
4829 {
4830         struct ipmi_recv_msg *rv;
4831
4832         rv = kmalloc(sizeof(struct ipmi_recv_msg), GFP_ATOMIC);
4833         if (rv) {
4834                 rv->user = NULL;
4835                 rv->done = free_recv_msg;
4836                 atomic_inc(&recv_msg_inuse_count);
4837         }
4838         return rv;
4839 }
4840
4841 void ipmi_free_recv_msg(struct ipmi_recv_msg *msg)
4842 {
4843         if (msg->user)
4844                 kref_put(&msg->user->refcount, free_user);
4845         msg->done(msg);
4846 }
4847 EXPORT_SYMBOL(ipmi_free_recv_msg);
4848
4849 static atomic_t panic_done_count = ATOMIC_INIT(0);
4850
4851 static void dummy_smi_done_handler(struct ipmi_smi_msg *msg)
4852 {
4853         atomic_dec(&panic_done_count);
4854 }
4855
4856 static void dummy_recv_done_handler(struct ipmi_recv_msg *msg)
4857 {
4858         atomic_dec(&panic_done_count);
4859 }
4860
4861 /*
4862  * Inside a panic, send a message and wait for a response.
4863  */
4864 static void ipmi_panic_request_and_wait(struct ipmi_smi *intf,
4865                                         struct ipmi_addr *addr,
4866                                         struct kernel_ipmi_msg *msg)
4867 {
4868         struct ipmi_smi_msg  smi_msg;
4869         struct ipmi_recv_msg recv_msg;
4870         int rv;
4871
4872         smi_msg.done = dummy_smi_done_handler;
4873         recv_msg.done = dummy_recv_done_handler;
4874         atomic_add(2, &panic_done_count);
4875         rv = i_ipmi_request(NULL,
4876                             intf,
4877                             addr,
4878                             0,
4879                             msg,
4880                             intf,
4881                             &smi_msg,
4882                             &recv_msg,
4883                             0,
4884                             intf->addrinfo[0].address,
4885                             intf->addrinfo[0].lun,
4886                             0, 1); /* Don't retry, and don't wait. */
4887         if (rv)
4888                 atomic_sub(2, &panic_done_count);
4889         else if (intf->handlers->flush_messages)
4890                 intf->handlers->flush_messages(intf->send_info);
4891
4892         while (atomic_read(&panic_done_count) != 0)
4893                 ipmi_poll(intf);
4894 }
4895
4896 static void event_receiver_fetcher(struct ipmi_smi *intf,
4897                                    struct ipmi_recv_msg *msg)
4898 {
4899         if ((msg->addr.addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
4900             && (msg->msg.netfn == IPMI_NETFN_SENSOR_EVENT_RESPONSE)
4901             && (msg->msg.cmd == IPMI_GET_EVENT_RECEIVER_CMD)
4902             && (msg->msg.data[0] == IPMI_CC_NO_ERROR)) {
4903                 /* A get event receiver command, save it. */
4904                 intf->event_receiver = msg->msg.data[1];
4905                 intf->event_receiver_lun = msg->msg.data[2] & 0x3;
4906         }
4907 }
4908
4909 static void device_id_fetcher(struct ipmi_smi *intf, struct ipmi_recv_msg *msg)
4910 {
4911         if ((msg->addr.addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
4912             && (msg->msg.netfn == IPMI_NETFN_APP_RESPONSE)
4913             && (msg->msg.cmd == IPMI_GET_DEVICE_ID_CMD)
4914             && (msg->msg.data[0] == IPMI_CC_NO_ERROR)) {
4915                 /*
4916                  * A get device id command, save if we are an event
4917                  * receiver or generator.
4918                  */
4919                 intf->local_sel_device = (msg->msg.data[6] >> 2) & 1;
4920                 intf->local_event_generator = (msg->msg.data[6] >> 5) & 1;
4921         }
4922 }
4923
4924 static void send_panic_events(struct ipmi_smi *intf, char *str)
4925 {
4926         struct kernel_ipmi_msg msg;
4927         unsigned char data[16];
4928         struct ipmi_system_interface_addr *si;
4929         struct ipmi_addr addr;
4930         char *p = str;
4931         struct ipmi_ipmb_addr *ipmb;
4932         int j;
4933
4934         if (ipmi_send_panic_event == IPMI_SEND_PANIC_EVENT_NONE)
4935                 return;
4936
4937         si = (struct ipmi_system_interface_addr *) &addr;
4938         si->addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
4939         si->channel = IPMI_BMC_CHANNEL;
4940         si->lun = 0;
4941
4942         /* Fill in an event telling that we have failed. */
4943         msg.netfn = 0x04; /* Sensor or Event. */
4944         msg.cmd = 2; /* Platform event command. */
4945         msg.data = data;
4946         msg.data_len = 8;
4947         data[0] = 0x41; /* Kernel generator ID, IPMI table 5-4 */
4948         data[1] = 0x03; /* This is for IPMI 1.0. */
4949         data[2] = 0x20; /* OS Critical Stop, IPMI table 36-3 */
4950         data[4] = 0x6f; /* Sensor specific, IPMI table 36-1 */
4951         data[5] = 0xa1; /* Runtime stop OEM bytes 2 & 3. */
4952
4953         /*
4954          * Put a few breadcrumbs in.  Hopefully later we can add more things
4955          * to make the panic events more useful.
4956          */
4957         if (str) {
4958                 data[3] = str[0];
4959                 data[6] = str[1];
4960                 data[7] = str[2];
4961         }
4962
4963         /* Send the event announcing the panic. */
4964         ipmi_panic_request_and_wait(intf, &addr, &msg);
4965
4966         /*
4967          * On every interface, dump a bunch of OEM event holding the
4968          * string.
4969          */
4970         if (ipmi_send_panic_event != IPMI_SEND_PANIC_EVENT_STRING || !str)
4971                 return;
4972
4973         /*
4974          * intf_num is used as an marker to tell if the
4975          * interface is valid.  Thus we need a read barrier to
4976          * make sure data fetched before checking intf_num
4977          * won't be used.
4978          */
4979         smp_rmb();
4980
4981         /*
4982          * First job here is to figure out where to send the
4983          * OEM events.  There's no way in IPMI to send OEM
4984          * events using an event send command, so we have to
4985          * find the SEL to put them in and stick them in
4986          * there.
4987          */
4988
4989         /* Get capabilities from the get device id. */
4990         intf->local_sel_device = 0;
4991         intf->local_event_generator = 0;
4992         intf->event_receiver = 0;
4993
4994         /* Request the device info from the local MC. */
4995         msg.netfn = IPMI_NETFN_APP_REQUEST;
4996         msg.cmd = IPMI_GET_DEVICE_ID_CMD;
4997         msg.data = NULL;
4998         msg.data_len = 0;
4999         intf->null_user_handler = device_id_fetcher;
5000         ipmi_panic_request_and_wait(intf, &addr, &msg);
5001
5002         if (intf->local_event_generator) {
5003                 /* Request the event receiver from the local MC. */
5004                 msg.netfn = IPMI_NETFN_SENSOR_EVENT_REQUEST;
5005                 msg.cmd = IPMI_GET_EVENT_RECEIVER_CMD;
5006                 msg.data = NULL;
5007                 msg.data_len = 0;
5008                 intf->null_user_handler = event_receiver_fetcher;
5009                 ipmi_panic_request_and_wait(intf, &addr, &msg);
5010         }
5011         intf->null_user_handler = NULL;
5012
5013         /*
5014          * Validate the event receiver.  The low bit must not
5015          * be 1 (it must be a valid IPMB address), it cannot
5016          * be zero, and it must not be my address.
5017          */
5018         if (((intf->event_receiver & 1) == 0)
5019             && (intf->event_receiver != 0)
5020             && (intf->event_receiver != intf->addrinfo[0].address)) {
5021                 /*
5022                  * The event receiver is valid, send an IPMB
5023                  * message.
5024                  */
5025                 ipmb = (struct ipmi_ipmb_addr *) &addr;
5026                 ipmb->addr_type = IPMI_IPMB_ADDR_TYPE;
5027                 ipmb->channel = 0; /* FIXME - is this right? */
5028                 ipmb->lun = intf->event_receiver_lun;
5029                 ipmb->slave_addr = intf->event_receiver;
5030         } else if (intf->local_sel_device) {
5031                 /*
5032                  * The event receiver was not valid (or was
5033                  * me), but I am an SEL device, just dump it
5034                  * in my SEL.
5035                  */
5036                 si = (struct ipmi_system_interface_addr *) &addr;
5037                 si->addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
5038                 si->channel = IPMI_BMC_CHANNEL;
5039                 si->lun = 0;
5040         } else
5041                 return; /* No where to send the event. */
5042
5043         msg.netfn = IPMI_NETFN_STORAGE_REQUEST; /* Storage. */
5044         msg.cmd = IPMI_ADD_SEL_ENTRY_CMD;
5045         msg.data = data;
5046         msg.data_len = 16;
5047
5048         j = 0;
5049         while (*p) {
5050                 int size = strlen(p);
5051
5052                 if (size > 11)
5053                         size = 11;
5054                 data[0] = 0;
5055                 data[1] = 0;
5056                 data[2] = 0xf0; /* OEM event without timestamp. */
5057                 data[3] = intf->addrinfo[0].address;
5058                 data[4] = j++; /* sequence # */
5059                 /*
5060                  * Always give 11 bytes, so strncpy will fill
5061                  * it with zeroes for me.
5062                  */
5063                 strncpy(data+5, p, 11);
5064                 p += size;
5065
5066                 ipmi_panic_request_and_wait(intf, &addr, &msg);
5067         }
5068 }
5069
5070 static int has_panicked;
5071
5072 static int panic_event(struct notifier_block *this,
5073                        unsigned long         event,
5074                        void                  *ptr)
5075 {
5076         struct ipmi_smi *intf;
5077         struct ipmi_user *user;
5078
5079         if (has_panicked)
5080                 return NOTIFY_DONE;
5081         has_panicked = 1;
5082
5083         /* For every registered interface, set it to run to completion. */
5084         list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
5085                 if (!intf->handlers || intf->intf_num == -1)
5086                         /* Interface is not ready. */
5087                         continue;
5088
5089                 if (!intf->handlers->poll)
5090                         continue;
5091
5092                 /*
5093                  * If we were interrupted while locking xmit_msgs_lock or
5094                  * waiting_rcv_msgs_lock, the corresponding list may be
5095                  * corrupted.  In this case, drop items on the list for
5096                  * the safety.
5097                  */
5098                 if (!spin_trylock(&intf->xmit_msgs_lock)) {
5099                         INIT_LIST_HEAD(&intf->xmit_msgs);
5100                         INIT_LIST_HEAD(&intf->hp_xmit_msgs);
5101                 } else
5102                         spin_unlock(&intf->xmit_msgs_lock);
5103
5104                 if (!spin_trylock(&intf->waiting_rcv_msgs_lock))
5105                         INIT_LIST_HEAD(&intf->waiting_rcv_msgs);
5106                 else
5107                         spin_unlock(&intf->waiting_rcv_msgs_lock);
5108
5109                 intf->run_to_completion = 1;
5110                 if (intf->handlers->set_run_to_completion)
5111                         intf->handlers->set_run_to_completion(intf->send_info,
5112                                                               1);
5113
5114                 list_for_each_entry_rcu(user, &intf->users, link) {
5115                         if (user->handler->ipmi_panic_handler)
5116                                 user->handler->ipmi_panic_handler(
5117                                         user->handler_data);
5118                 }
5119
5120                 send_panic_events(intf, ptr);
5121         }
5122
5123         return NOTIFY_DONE;
5124 }
5125
5126 /* Must be called with ipmi_interfaces_mutex held. */
5127 static int ipmi_register_driver(void)
5128 {
5129         int rv;
5130
5131         if (drvregistered)
5132                 return 0;
5133
5134         rv = driver_register(&ipmidriver.driver);
5135         if (rv)
5136                 pr_err("Could not register IPMI driver\n");
5137         else
5138                 drvregistered = true;
5139         return rv;
5140 }
5141
5142 static struct notifier_block panic_block = {
5143         .notifier_call  = panic_event,
5144         .next           = NULL,
5145         .priority       = 200   /* priority: INT_MAX >= x >= 0 */
5146 };
5147
5148 static int ipmi_init_msghandler(void)
5149 {
5150         int rv;
5151
5152         mutex_lock(&ipmi_interfaces_mutex);
5153         rv = ipmi_register_driver();
5154         if (rv)
5155                 goto out;
5156         if (initialized)
5157                 goto out;
5158
5159         init_srcu_struct(&ipmi_interfaces_srcu);
5160
5161         timer_setup(&ipmi_timer, ipmi_timeout, 0);
5162         mod_timer(&ipmi_timer, jiffies + IPMI_TIMEOUT_JIFFIES);
5163
5164         atomic_notifier_chain_register(&panic_notifier_list, &panic_block);
5165
5166         initialized = true;
5167
5168 out:
5169         mutex_unlock(&ipmi_interfaces_mutex);
5170         return rv;
5171 }
5172
5173 static int __init ipmi_init_msghandler_mod(void)
5174 {
5175         int rv;
5176
5177         pr_info("version " IPMI_DRIVER_VERSION "\n");
5178
5179         mutex_lock(&ipmi_interfaces_mutex);
5180         rv = ipmi_register_driver();
5181         mutex_unlock(&ipmi_interfaces_mutex);
5182
5183         return rv;
5184 }
5185
5186 static void __exit cleanup_ipmi(void)
5187 {
5188         int count;
5189
5190         if (initialized) {
5191                 atomic_notifier_chain_unregister(&panic_notifier_list,
5192                                                  &panic_block);
5193
5194                 /*
5195                  * This can't be called if any interfaces exist, so no worry
5196                  * about shutting down the interfaces.
5197                  */
5198
5199                 /*
5200                  * Tell the timer to stop, then wait for it to stop.  This
5201                  * avoids problems with race conditions removing the timer
5202                  * here.
5203                  */
5204                 atomic_set(&stop_operation, 1);
5205                 del_timer_sync(&ipmi_timer);
5206
5207                 initialized = false;
5208
5209                 /* Check for buffer leaks. */
5210                 count = atomic_read(&smi_msg_inuse_count);
5211                 if (count != 0)
5212                         pr_warn("SMI message count %d at exit\n", count);
5213                 count = atomic_read(&recv_msg_inuse_count);
5214                 if (count != 0)
5215                         pr_warn("recv message count %d at exit\n", count);
5216
5217                 cleanup_srcu_struct(&ipmi_interfaces_srcu);
5218         }
5219         if (drvregistered)
5220                 driver_unregister(&ipmidriver.driver);
5221 }
5222 module_exit(cleanup_ipmi);
5223
5224 module_init(ipmi_init_msghandler_mod);
5225 MODULE_LICENSE("GPL");
5226 MODULE_AUTHOR("Corey Minyard <minyard@mvista.com>");
5227 MODULE_DESCRIPTION("Incoming and outgoing message routing for an IPMI"
5228                    " interface.");
5229 MODULE_VERSION(IPMI_DRIVER_VERSION);
5230 MODULE_SOFTDEP("post: ipmi_devintf");