drivers/char/ipmi/ipmi_msghandler.c

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