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