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