diff options
Diffstat (limited to 'drivers/char/ipmi')
| -rw-r--r-- | drivers/char/ipmi/ipmi_msghandler.c | 953 |
1 files changed, 498 insertions, 455 deletions
diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c index 32fa82c78c7..320d7f035bf 100644 --- a/drivers/char/ipmi/ipmi_msghandler.c +++ b/drivers/char/ipmi/ipmi_msghandler.c @@ -38,13 +38,13 @@ #include <linux/sched.h> #include <linux/poll.h> #include <linux/spinlock.h> -#include <linux/rwsem.h> #include <linux/slab.h> #include <linux/ipmi.h> #include <linux/ipmi_smi.h> #include <linux/notifier.h> #include <linux/init.h> #include <linux/proc_fs.h> +#include <linux/rcupdate.h> #define PFX "IPMI message handler: " @@ -65,10 +65,19 @@ struct proc_dir_entry *proc_ipmi_root = NULL; the max message timer. This is in milliseconds. */ #define MAX_MSG_TIMEOUT 60000 + +/* + * The main "user" data structure. + */ struct ipmi_user { struct list_head link; + /* Set to "0" when the user is destroyed. */ + int valid; + + struct kref refcount; + /* The upper layer that handles receive messages. */ struct ipmi_user_hndl *handler; void *handler_data; @@ -87,6 +96,15 @@ struct cmd_rcvr ipmi_user_t user; unsigned char netfn; unsigned char cmd; + + /* + * This is used to form a linked lised during mass deletion. + * Since this is in an RCU list, we cannot use the link above + * or change any data until the RCU period completes. So we + * use this next variable during mass deletion so we can have + * a list and don't have to wait and restart the search on + * every individual deletion of a command. */ + struct cmd_rcvr *next; }; struct seq_table @@ -150,13 +168,11 @@ struct ipmi_smi /* What interface number are we? */ int intf_num; - /* The list of upper layers that are using me. We read-lock - this when delivering messages to the upper layer to keep - the user from going away while we are processing the - message. This means that you cannot add or delete a user - from the receive callback. */ - rwlock_t users_lock; - struct list_head users; + struct kref refcount; + + /* The list of upper layers that are using me. seq_lock + * protects this. */ + struct list_head users; /* Used for wake ups at startup. */ wait_queue_head_t waitq; @@ -193,7 +209,7 @@ struct ipmi_smi /* The list of command receivers that are registered for commands on this interface. */ - rwlock_t cmd_rcvr_lock; + spinlock_t cmd_rcvrs_lock; struct list_head cmd_rcvrs; /* Events that were queues because no one was there to receive @@ -296,16 +312,17 @@ struct ipmi_smi unsigned int events; }; +/* Used to mark an interface entry that cannot be used but is not a + * free entry, either, primarily used at creation and deletion time so + * a slot doesn't get reused too quickly. */ +#define IPMI_INVALID_INTERFACE_ENTRY ((ipmi_smi_t) ((long) 1)) +#define IPMI_INVALID_INTERFACE(i) (((i) == NULL) \ + || (i == IPMI_INVALID_INTERFACE_ENTRY)) + #define MAX_IPMI_INTERFACES 4 static ipmi_smi_t ipmi_interfaces[MAX_IPMI_INTERFACES]; -/* Used to keep interfaces from going away while operations are - operating on interfaces. Grab read if you are not modifying the - interfaces, write if you are. */ -static DECLARE_RWSEM(interfaces_sem); - -/* Directly protects the ipmi_interfaces data structure. This is - claimed in the timer interrupt. */ +/* Directly protects the ipmi_interfaces data structure. */ static DEFINE_SPINLOCK(interfaces_lock); /* List of watchers that want to know when smi's are added and @@ -313,20 +330,73 @@ static DEFINE_SPINLOCK(interfaces_lock); static struct list_head smi_watchers = LIST_HEAD_INIT(smi_watchers); static DECLARE_RWSEM(smi_watchers_sem); + +static void free_recv_msg_list(struct list_head *q) +{ + struct ipmi_recv_msg *msg, *msg2; + + list_for_each_entry_safe(msg, msg2, q, link) { + list_del(&msg->link); + ipmi_free_recv_msg(msg); + } +} + +static void clean_up_interface_data(ipmi_smi_t intf) +{ + int i; + struct cmd_rcvr *rcvr, *rcvr2; + unsigned long flags; + struct list_head list; + + free_recv_msg_list(&intf->waiting_msgs); + free_recv_msg_list(&intf->waiting_events); + + /* Wholesale remove all the entries from the list in the + * interface and wait for RCU to know that none are in use. */ + spin_lock_irqsave(&intf->cmd_rcvrs_lock, flags); + list_add_rcu(&list, &intf->cmd_rcvrs); + list_del_rcu(&intf->cmd_rcvrs); + spin_unlock_irqrestore(&intf->cmd_rcvrs_lock, flags); + synchronize_rcu(); + + list_for_each_entry_safe(rcvr, rcvr2, &list, link) + kfree(rcvr); + + for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++) { + if ((intf->seq_table[i].inuse) + && (intf->seq_table[i].recv_msg)) + { + ipmi_free_recv_msg(intf->seq_table[i].recv_msg); + } + } +} + +static void intf_free(struct kref *ref) +{ + ipmi_smi_t intf = container_of(ref, struct ipmi_smi, refcount); + + clean_up_interface_data(intf); + kfree(intf); +} + int ipmi_smi_watcher_register(struct ipmi_smi_watcher *watcher) { - int i; + int i; + unsigned long flags; - down_read(&interfaces_sem); down_write(&smi_watchers_sem); list_add(&(watcher->link), &smi_watchers); + up_write(&smi_watchers_sem); + spin_lock_irqsave(&interfaces_lock, flags); for (i = 0; i < MAX_IPMI_INTERFACES; i++) { - if (ipmi_interfaces[i] != NULL) { - watcher->new_smi(i); - } + ipmi_smi_t intf = ipmi_interfaces[i]; + if (IPMI_INVALID_INTERFACE(intf)) + continue; + spin_unlock_irqrestore(&interfaces_lock, flags); + watcher->new_smi(i); + spin_lock_irqsave(&interfaces_lock, flags); } - up_write(&smi_watchers_sem); - up_read(&interfaces_sem); + spin_unlock_irqrestore(&interfaces_lock, flags); return 0; } @@ -471,8 +541,8 @@ static void deliver_response(struct ipmi_recv_msg *msg) } ipmi_free_recv_msg(msg); } else { - msg->user->handler->ipmi_recv_hndl(msg, - msg->user->handler_data); + ipmi_user_t user = msg->user; + user->handler->ipmi_recv_hndl(msg, user->handler_data); } } @@ -662,15 +732,18 @@ int ipmi_create_user(unsigned int if_num, if (! new_user) return -ENOMEM; - down_read(&interfaces_sem); - if ((if_num >= MAX_IPMI_INTERFACES) || ipmi_interfaces[if_num] == NULL) - { - rv = -EINVAL; - goto out_unlock; + spin_lock_irqsave(&interfaces_lock, flags); + intf = ipmi_interfaces[if_num]; + if ((if_num >= MAX_IPMI_INTERFACES) || IPMI_INVALID_INTERFACE(intf)) { + spin_unlock_irqrestore(&interfaces_lock, flags); + return -EINVAL; } - intf = ipmi_interfaces[if_num]; + /* Note that each existing user holds a refcount to the interface. */ + kref_get(&intf->refcount); + spin_unlock_irqrestore(&interfaces_lock, flags); + kref_init(&new_user->refcount); new_user->handler = handler; new_user->handler_data = handler_data; new_user->intf = intf; @@ -678,98 +751,92 @@ int ipmi_create_user(unsigned int if_num, if (!try_module_get(intf->handlers->owner)) { rv = -ENODEV; - goto out_unlock; + goto out_err; } if (intf->handlers->inc_usecount) { rv = intf->handlers->inc_usecount(intf->send_info); if (rv) { module_put(intf->handlers->owner); - goto out_unlock; + goto out_err; } } - write_lock_irqsave(&intf->users_lock, flags); - list_add_tail(&new_user->link, &intf->users); - write_unlock_irqrestore(&intf->users_lock, flags); - - out_unlock: - if (rv) { - kfree(new_user); - } else { - *user = new_user; - } + new_user->valid = 1; + spin_lock_irqsave(&intf->seq_lock, flags); + list_add_rcu(&new_user->link, &intf->users); + spin_unlock_irqrestore(&intf->seq_lock, flags); + *user = new_user; + return 0; - up_read(&interfaces_sem); + out_err: + kfree(new_user); + kref_put(&intf->refcount, intf_free); return rv; } -static int ipmi_destroy_user_nolock(ipmi_user_t user) +static void free_user(struct kref *ref) +{ + ipmi_user_t user = container_of(ref, struct ipmi_user, refcount); + kfree(user); +} + +int ipmi_destroy_user(ipmi_user_t user) { int rv = -ENODEV; - ipmi_user_t t_user; - struct cmd_rcvr *rcvr, *rcvr2; + ipmi_smi_t intf = user->intf; int i; unsigned long flags; + struct cmd_rcvr *rcvr; + struct list_head *entry1, *entry2; + struct cmd_rcvr *rcvrs = NULL; - /* Find the user and delete them from the list. */ - list_for_each_entry(t_user, &(user->intf->users), link) { - if (t_user == user) { - list_del(&t_user->link); - rv = 0; - break; - } - } + user->valid = 1; - if (rv) { - goto out_unlock; - } + /* Remove the user from the interface's sequence table. */ + spin_lock_irqsave(&intf->seq_lock, flags); + list_del_rcu(&user->link); - /* Remove the user from the interfaces sequence table. */ - spin_lock_irqsave(&(user->intf->seq_lock), flags); for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++) { - if (user->intf->seq_table[i].inuse - && (user->intf->seq_table[i].recv_msg->user == user)) + if (intf->seq_table[i].inuse + && (intf->seq_table[i].recv_msg->user == user)) { - user->intf->seq_table[i].inuse = 0; + intf->seq_table[i].inuse = 0; } } - spin_unlock_irqrestore(&(user->intf->seq_lock), flags); - - /* Remove the user from the command receiver's table. */ - write_lock_irqsave(&(user->intf->cmd_rcvr_lock), flags); - list_for_each_entry_safe(rcvr, rcvr2, &(user->intf->cmd_rcvrs), link) { + spin_unlock_irqrestore(&intf->seq_lock, flags); + + /* + * Remove the user from the command receiver's table. First + * we build a list of everything (not using the standard link, + * since other things may be using it till we do + * synchronize_rcu()) then free everything in that list. + */ + spin_lock_irqsave(&intf->cmd_rcvrs_lock, flags); + list_for_each_safe_rcu(entry1, entry2, &intf->cmd_rcvrs) { + rcvr = list_entry(entry1, struct cmd_rcvr, link); if (rcvr->user == user) { - list_del(&rcvr->link); - kfree(rcvr); + list_del_rcu(&rcvr->link); + rcvr->next = rcvrs; + rcvrs = rcvr; } } - write_unlock_irqrestore(&(user->intf->cmd_rcvr_lock), flags); + spin_unlock_irqrestore(&intf->cmd_rcvrs_lock, flags); + synchronize_rcu(); + while (rcvrs) { + rcvr = rcvrs; + rcvrs = rcvr->next; + kfree(rcvr); + } - kfree(user); + module_put(intf->handlers->owner); + if (intf->handlers->dec_usecount) + intf->handlers->dec_usecount(intf->send_info); - out_unlock: + kref_put(&intf->refcount, intf_free); - return rv; -} - -int ipmi_destroy_user(ipmi_user_t user) -{ - int rv; - ipmi_smi_t intf = user->intf; - unsigned long flags; + kref_put(&user->refcount, free_user); - down_read(&interfaces_sem); - write_lock_irqsave(&intf->users_lock, flags); - rv = ipmi_destroy_user_nolock(user); - if (!rv) { - module_put(intf->handlers->owner); - if (intf->handlers->dec_usecount) - intf->handlers->dec_usecount(intf->send_info); - } - - write_unlock_irqrestore(&intf->users_lock, flags); - up_read(&interfaces_sem); return rv; } @@ -823,62 +890,78 @@ int ipmi_get_my_LUN(ipmi_user_t user, int ipmi_set_gets_events(ipmi_user_t user, int val) { - unsigned long flags; - struct ipmi_recv_msg *msg, *msg2; + unsigned long flags; + ipmi_smi_t intf = user->intf; + struct ipmi_recv_msg *msg, *msg2; + struct list_head msgs; - read_lock(&(user->intf->users_lock)); - spin_lock_irqsave(&(user->intf->events_lock), flags); + INIT_LIST_HEAD(&msgs); + + spin_lock_irqsave(&intf->events_lock, flags); user->gets_events = val; if (val) { /* Deliver any queued events. */ - list_for_each_entry_safe(msg, msg2, &(user->intf->waiting_events), link) { + list_for_each_entry_safe(msg, msg2, &intf->waiting_events, link) { list_del(&msg->link); - msg->user = user; - deliver_response(msg); + list_add_tail(&msg->link, &msgs); } } - - spin_unlock_irqrestore(&(user->intf->events_lock), flags); - read_unlock(&(user->intf->users_lock)); + + /* Hold the events lock while doing this to preserve order. */ + list_for_each_entry_safe(msg, msg2, &msgs, link) { + msg->user = user; + kref_get(&user->refcount); + deliver_response(msg); + } + + spin_unlock_irqrestore(&intf->events_lock, flags); return 0; } +static struct cmd_rcvr *find_cmd_rcvr(ipmi_smi_t intf, + unsigned char netfn, + unsigned char cmd) +{ + struct cmd_rcvr *rcvr; + + list_for_each_entry_rcu(rcvr, &intf->cmd_rcvrs, link) { + if ((rcvr->netfn == netfn) && (rcvr->cmd == cmd)) + return rcvr; + } + return NULL; +} + int ipmi_register_for_cmd(ipmi_user_t user, unsigned char netfn, unsigned char cmd) { - struct cmd_rcvr *cmp; - unsigned long flags; - struct cmd_rcvr *rcvr; - int rv = 0; + ipmi_smi_t intf = user->intf; + struct cmd_rcvr *rcvr; + struct cmd_rcvr *entry; + int rv = 0; rcvr = kmalloc(sizeof(*rcvr), GFP_KERNEL); if (! rcvr) return -ENOMEM; + rcvr->cmd = cmd; + rcvr->netfn = netfn; + rcvr->user = user; - read_lock(&(user->intf->users_lock)); - write_lock_irqsave(&(user->intf->cmd_rcvr_lock), flags); + spin_lock_irq(&intf->cmd_rcvrs_lock); /* Make sure the command/netfn is not already registered. */ - list_for_each_entry(cmp, &(user->intf->cmd_rcvrs), link) { - if ((cmp->netfn == netfn) && (cmp->cmd == cmd)) { - rv = -EBUSY; - break; - } - } - - if (! rv) { - rcvr->cmd = cmd; - rcvr->netfn = netfn; - rcvr->user = user; - list_add_tail(&(rcvr->link), &(user->intf->cmd_rcvrs)); + entry = find_cmd_rcvr(intf, netfn, cmd); + if (entry) { + rv = -EBUSY; + goto out_unlock; } - write_unlock_irqrestore(&(user->intf->cmd_rcvr_lock), flags); - read_unlock(&(user->intf->users_lock)); + list_add_rcu(&rcvr->link, &intf->cmd_rcvrs); + out_unlock: + spin_unlock_irq(&intf->cmd_rcvrs_lock); if (rv) kfree(rcvr); @@ -889,31 +972,28 @@ int ipmi_unregister_for_cmd(ipmi_user_t user, unsigned char netfn, unsigned char cmd) { - unsigned long flags; - struct cmd_rcvr *rcvr; - int rv = -ENOENT; + ipmi_smi_t intf = user->intf; + struct cmd_rcvr *rcvr; - read_lock(&(user->intf->users_lock)); - write_lock_irqsave(&(user->intf->cmd_rcvr_lock), flags); + spin_lock_irq(&intf->cmd_rcvrs_lock); /* Make sure the command/netfn is not already registered. */ - list_for_each_entry(rcvr, &(user->intf->cmd_rcvrs), link) { - if ((rcvr->netfn == netfn) && (rcvr->cmd == cmd)) { - rv = 0; - list_del(&rcvr->link); - kfree(rcvr); - break; - } + rcvr = find_cmd_rcvr(intf, netfn, cmd); + if ((rcvr) && (rcvr->user == user)) { + list_del_rcu(&rcvr->link); + spin_unlock_irq(&intf->cmd_rcvrs_lock); + synchronize_rcu(); + kfree(rcvr); + return 0; + } else { + spin_unlock_irq(&intf->cmd_rcvrs_lock); + return -ENOENT; } - write_unlock_irqrestore(&(user->intf->cmd_rcvr_lock), flags); - read_unlock(&(user->intf->users_lock)); - - return rv; } void ipmi_user_set_run_to_completion(ipmi_user_t user, int val) { - user->intf->handlers->set_run_to_completion(user->intf->send_info, - val); + ipmi_smi_t intf = user->intf; + intf->handlers->set_run_to_completion(intf->send_info, val); } static unsigned char @@ -1010,19 +1090,19 @@ static inline void format_lan_msg(struct ipmi_smi_msg *smi_msg, supplied in certain circumstances (mainly at panic time). If messages are supplied, they will be freed, even if an error occurs. */ -static inline int i_ipmi_request(ipmi_user_t user, - ipmi_smi_t intf, - struct ipmi_addr *addr, - long msgid, - struct kernel_ipmi_msg *msg, - void *user_msg_data, - void *supplied_smi, - struct ipmi_recv_msg *supplied_recv, - int priority, - unsigned char source_address, - unsigned char source_lun, - int retries, - unsigned int retry_time_ms) +static int i_ipmi_request(ipmi_user_t user, + ipmi_smi_t intf, + struct ipmi_addr *addr, + long msgid, + struct kernel_ipmi_msg *msg, + void *user_msg_data, + void *supplied_smi, + struct ipmi_recv_msg *supplied_recv, + int priority, + unsigned char source_address, + unsigned char source_lun, + int retries, + unsigned int retry_time_ms) { int rv = 0; struct ipmi_smi_msg *smi_msg; @@ -1051,6 +1131,8 @@ static inline int i_ipmi_request(ipmi_user_t user, } recv_msg->user = user; + if (user) + kref_get(&user->refcount); recv_msg->msgid = msgid; /* Store the message to send in the receive message so timeout responses can get the proper response data. */ @@ -1725,11 +1807,11 @@ int ipmi_register_smi(struct ipmi_smi_handlers *handlers, unsigned char version_major, unsigned char version_minor, unsigned char slave_addr, - ipmi_smi_t *intf) + ipmi_smi_t *new_intf) { int i, j; int rv; - ipmi_smi_t new_intf; + ipmi_smi_t intf; unsigned long flags; @@ -1745,189 +1827,142 @@ int ipmi_register_smi(struct ipmi_smi_handlers *handlers, return -ENODEV; } - new_intf = kmalloc(sizeof(*new_intf), GFP_KERNEL); - if (!new_intf) + intf = kmalloc(sizeof(*intf), GFP_KERNEL); + if (!intf) return -ENOMEM; - memset(new_intf, 0, sizeof(*new_intf)); - - new_intf->proc_dir = NULL; + memset(intf, 0, sizeof(*intf)); + intf->intf_num = -1; + kref_init(&intf->refcount); + intf->version_major = version_major; + intf->version_minor = version_minor; + for (j = 0; j < IPMI_MAX_CHANNELS; j++) { + intf->channels[j].address = IPMI_BMC_SLAVE_ADDR; + intf->channels[j].lun = 2; + } + if (slave_addr != 0) + intf->channels[0].address = slave_addr; + INIT_LIST_HEAD(&intf->users); + intf->handlers = handlers; + intf->send_info = send_info; + spin_lock_init(&intf->seq_lock); + for (j = 0; j < IPMI_IPMB_NUM_SEQ; j++) { + intf->seq_table[j].inuse = 0; + intf->seq_table[j].seqid = 0; + } + intf->curr_seq = 0; +#ifdef CONFIG_PROC_FS + spin_lock_init(&intf->proc_entry_lock); +#endif + spin_lock_init(&intf->waiting_msgs_lock); + INIT_LIST_HEAD(&intf->waiting_msgs); + spin_lock_init(&intf->events_lock); + INIT_LIST_HEAD(&intf->waiting_events); + intf->waiting_events_count = 0; + spin_lock_init(&intf->cmd_rcvrs_lock); + INIT_LIST_HEAD(&intf->cmd_rcvrs); + init_waitqueue_head(&intf->waitq); + + spin_lock_init(&intf->counter_lock); + intf->proc_dir = NULL; rv = -ENOMEM; - - down_write(&interfaces_sem); + spin_lock_irqsave(&interfaces_lock, flags); for (i = 0; i < MAX_IPMI_INTERFACES; i++) { if (ipmi_interfaces[i] == NULL) { - new_intf->intf_num = i; - new_intf->version_major = version_major; - new_intf->version_minor = version_minor; - for (j = 0; j < IPMI_MAX_CHANNELS; j++) { - new_intf->channels[j].address - = IPMI_BMC_SLAVE_ADDR; - new_intf->channels[j].lun = 2; - } - if (slave_addr != 0) - new_intf->channels[0].address = slave_addr; - rwlock_init(&(new_intf->users_lock)); - INIT_LIST_HEAD(&(new_intf->users)); - new_intf->handlers = handlers; - new_intf->send_info = send_info; - spin_lock_init(&(new_intf->seq_lock)); - for (j = 0; j < IPMI_IPMB_NUM_SEQ; j++) { - new_intf->seq_table[j].inuse = 0; - new_intf->seq_table[j].seqid = 0; - } - new_intf->curr_seq = 0; -#ifdef CONFIG_PROC_FS - spin_lock_init(&(new_intf->proc_entry_lock)); -#endif - spin_lock_init(&(new_intf->waiting_msgs_lock)); - INIT_LIST_HEAD(&(new_intf->waiting_msgs)); - spin_lock_init(&(new_intf->events_lock)); - INIT_LIST_HEAD(&(new_intf->waiting_events)); - new_intf->waiting_events_count = 0; - rwlock_init(&(new_intf->cmd_rcvr_lock)); - init_waitqueue_head(&new_intf->waitq); - INIT_LIST_HEAD(&(new_intf->cmd_rcvrs)); - - spin_lock_init(&(new_intf->counter_lock)); - - spin_lock_irqsave(&interfaces_lock, flags); - ipmi_interfaces[i] = new_intf; - spin_unlock_irqrestore(&interfaces_lock, flags); - + intf->intf_num = i; + /* Reserve the entry till we are done. */ + ipmi_interfaces[i] = IPMI_INVALID_INTERFACE_ENTRY; rv = 0; - *intf = new_intf; break; } } + spin_unlock_irqrestore(&interfaces_lock, flags); + if (rv) + goto out; - downgrade_write(&interfaces_sem); - - if (rv == 0) - rv = add_proc_entries(*intf, i); - - if (rv == 0) { - if ((version_major > 1) - || ((version_major == 1) && (version_minor >= 5))) - { - /* Start scanning the channels to see what is - available. */ - (*intf)->null_user_handler = channel_handler; - (*intf)->curr_channel = 0; - rv = send_channel_info_cmd(*intf, 0); - if (rv) - goto out; + /* FIXME - this is an ugly kludge, this sets the intf for the + caller before sending any messages with it. */ + *new_intf = intf; - /* Wait for the channel info to be read. */ - up_read(&interfaces_sem); - wait_event((*intf)->waitq, - ((*intf)->curr_channel>=IPMI_MAX_CHANNELS)); - down_read(&interfaces_sem); + if ((version_major > 1) + || ((version_major == 1) && (version_minor >= 5))) + { + /* Start scanning the channels to see what is + available. */ + intf->null_user_handler = channel_handler; + intf->curr_channel = 0; + rv = send_channel_info_cmd(intf, 0); + if (rv) + goto out; - if (ipmi_interfaces[i] != new_intf) - /* Well, it went away. Just return. */ - goto out; - } else { - /* Assume a single IPMB channel at zero. */ - (*intf)->channels[0].medium = IPMI_CHANNEL_MEDIUM_IPMB; - (*intf)->channels[0].protocol - = IPMI_CHANNEL_PROTOCOL_IPMB; - } - - /* Call all the watcher interfaces to tell - them that a new interface is available. */ - call_smi_watchers(i); + /* Wait for the channel info to be read. */ + wait_event(intf->waitq, + intf->curr_channel >= IPMI_MAX_CHANNELS); + } else { + /* Assume a single IPMB channel at zero. */ + intf->channels[0].medium = IPMI_CHANNEL_MEDIUM_IPMB; + intf->channels[0].protocol = IPMI_CHANNEL_PROTOCOL_IPMB; } - out: - up_read(&interfaces_sem); + if (rv == 0) + rv = add_proc_entries(intf, i); + out: if (rv) { - if (new_intf->proc_dir) - remove_proc_entries(new_intf); - kfree(new_intf); + if (intf->proc_dir) + remove_proc_entries(intf); + kref_put(&intf->refcount, intf_free); + if (i < MAX_IPMI_INTERFACES) { + spin_lock_irqsave(&interfaces_lock, flags); + ipmi_interfaces[i] = NULL; + spin_unlock_irqrestore(&interfaces_lock, flags); + } + } else { + spin_lock_irqsave(&interfaces_lock, flags); + ipmi_interfaces[i] = intf; + spin_unlock_irqrestore(&interfaces_lock, flags); + call_smi_watchers(i); } return rv; } -static void free_recv_msg_list(struct list_head *q) -{ - struct ipmi_recv_msg *msg, *msg2; - - list_for_each_entry_safe(msg, msg2, q, link) { - list_del(&msg->link); - ipmi_free_recv_msg(msg); - } -} - -static void free_cmd_rcvr_list(struct list_head *q) -{ - struct cmd_rcvr *rcvr, *rcvr2; - - list_for_each_entry_safe(rcvr, rcvr2, q, link) { - list_del(&rcvr->link); - kfree(rcvr); - } -} - -static void clean_up_interface_data(ipmi_smi_t intf) -{ - int i; - - free_recv_msg_list(&(intf->waiting_msgs)); - free_recv_msg_list(&(intf->waiting_events)); - free_cmd_rcvr_list(&(intf->cmd_rcvrs)); - - for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++) { - if ((intf->seq_table[i].inuse) - && (intf->seq_table[i].recv_msg)) - { - ipmi_free_recv_msg(intf->seq_table[i].recv_msg); - } - } -} - int ipmi_unregister_smi(ipmi_smi_t intf) { - int rv = -ENODEV; int i; struct ipmi_smi_watcher *w; unsigned long flags; - down_write(&interfaces_sem); - if (list_empty(&(intf->users))) - { - for (i = 0; i < MAX_IPMI_INTERFACES; i++) { - if (ipmi_interfaces[i] == intf) { - remove_proc_entries(intf); - spin_lock_irqsave(&interfaces_lock, flags); - ipmi_interfaces[i] = NULL; - clean_up_interface_data(intf); - spin_unlock_irqrestore(&interfaces_lock,flags); - kfree(intf); - rv = 0; - goto out_call_watcher; - } + spin_lock_irqsave(&interfaces_lock, flags); + for (i = 0; i < MAX_IPMI_INTERFACES; i++) { + if (ipmi_interfaces[i] == intf) { + /* Set the interface number reserved until we + * are done. */ + ipmi_interfaces[i] = IPMI_INVALID_INTERFACE_ENTRY; + intf->intf_num = -1; + break; } - } else { - rv = -EBUSY; } - up_write(&interfaces_sem); + spin_unlock_irqrestore(&interfaces_lock,flags); - return rv; + if (i == MAX_IPMI_INTERFACES) + return -ENODEV; - out_call_watcher: - downgrade_write(&interfaces_sem); + remove_proc_entries(intf); /* Call all the watcher interfaces to tell them that an interface is gone. */ down_read(&smi_watchers_sem); - list_for_each_entry(w, &smi_watchers, link) { + list_for_each_entry(w, &smi_watchers, link) w->smi_gone(i); - } up_read(&smi_watchers_sem); - up_read(&interfaces_sem); + + /* Allow the entry to be reused now. */ + spin_lock_irqsave(&interfaces_lock, flags); + ipmi_interfaces[i] = NULL; + spin_unlock_irqrestore(&interfaces_lock,flags); + + kref_put(&intf->refcount, intf_free); return 0; } @@ -1998,14 +2033,14 @@ static int handle_ipmb_get_msg_rsp(ipmi_smi_t intf, static int handle_ipmb_get_msg_cmd(ipmi_smi_t intf, struct ipmi_smi_msg *msg) { - struct cmd_rcvr *rcvr; - int rv = 0; - unsigned char netfn; - unsigned char cmd; - ipmi_user_t user = NULL; - struct ipmi_ipmb_addr *ipmb_addr; - struct ipmi_recv_msg *recv_msg; - unsigned long flags; + struct cmd_rcvr *rcvr; + int rv = 0; + unsigned char netfn; + unsigned char cmd; + ipmi_user_t user = NULL; + struct ipmi_ipmb_addr *ipmb_addr; + struct ipmi_recv_msg *recv_msg; + unsigned long flags; if (msg->rsp_size < 10) { /* Message not big enough, just ignore it. */ @@ -2023,16 +2058,14 @@ static int handle_ipmb_get_msg_cmd(ipmi_smi_t intf, netfn = msg->rsp[4] >> 2; cmd = msg->rsp[8]; - read_lock(&(intf->cmd_rcvr_lock)); - - /* Find the command/netfn. */ - list_for_each_entry(rcvr, &(intf->cmd_rcvrs), link) { - if ((rcvr->netfn == netfn) && (rcvr->cmd == cmd)) { - user = rcvr->user; - break; - } - } - read_unlock(&(intf->cmd_rcvr_lock)); + spin_lock_irqsave(&intf->cmd_rcvrs_lock, flags); + rcvr = find_cmd_rcvr(intf, netfn, cmd); + if (rcvr) { + user = rcvr->user; + kref_get(&user->refcount); + } else + user = NULL; + spin_unlock_irqrestore(&intf->cmd_rcvrs_lock, flags); if (user == NULL) { /* We didn't find a user, deliver an error response. */ @@ -2079,6 +2112,7 @@ static int handle_ipmb_get_msg_cmd(ipmi_smi_t intf, message, so requeue it for handling later. */ rv = 1; + kref_put(&user->refcount, free_user); } else { /* Extract the source address from the data. */ ipmb_addr = (struct ipmi_ipmb_addr *) &recv_msg->addr; @@ -2179,14 +2213,14 @@ static int handle_lan_get_msg_rsp(ipmi_smi_t intf, static int handle_lan_get_msg_cmd(ipmi_smi_t intf, struct ipmi_smi_msg *msg) { - struct cmd_rcvr *rcvr; - int rv = 0; - unsigned char netfn; - unsigned char cmd; - ipmi_user_t user = NULL; - struct ipmi_lan_addr *lan_addr; - struct ipmi_recv_msg *recv_msg; - unsigned long flags; + struct cmd_rcvr *rcvr; + int rv = 0; + unsigned char netfn; + unsigned char cmd; + ipmi_user_t user = NULL; + struct ipmi_lan_addr *lan_addr; + struct ipmi_recv_msg *recv_msg; + unsigned long flags; if (msg->rsp_size < 12) { /* Message not big enough, just ignore it. */ @@ -2204,19 +2238,17 @@ static int handle_lan_get_msg_cmd(ipmi_smi_t intf, netfn = msg->rsp[6] >> 2; cmd = msg->rsp[10]; - read_lock(&(intf->cmd_rcvr_lock)); - - /* Find the command/netfn. */ - list_for_each_entry(rcvr, &(intf->cmd_rcvrs), link) { - if ((rcvr->netfn == netfn) && (rcvr->cmd == cmd)) { - user = rcvr->user; - break; - } - } - read_unlock(&(intf->cmd_rcvr_lock)); + spin_lock_irqsave(&intf->cmd_rcvrs_lock, flags); + rcvr = find_cmd_rcvr(intf, netfn, cmd); + if (rcvr) { + user = rcvr->user; + kref_get(&user->refcount); + } else + user = NULL; + spin_unlock_irqrestore(&intf->cmd_rcvrs_lock, flags); if (user == NULL) { - /* We didn't find a user, deliver an error response. */ + /* We didn't find a user, just give up. */ spin_lock_irqsave(&intf->counter_lock, flags); intf->unhandled_commands++; spin_unlock_irqrestore(&intf->counter_lock, flags); @@ -2235,6 +2267,7 @@ static int handle_lan_get_msg_cmd(ipmi_smi_t intf, message, so requeue it for handling later. */ rv = 1; + kref_put(&user->refcount, free_user); } else { /* Extract the source address from the data. */ lan_addr = (struct ipmi_lan_addr *) &recv_msg->addr; @@ -2286,8 +2319,6 @@ static void copy_event_into_recv_msg(struct ipmi_recv_msg *recv_msg, recv_msg->msg.data_len = msg->rsp_size - 3; } -/* This will be called with the intf->users_lock read-locked, so no need - to do that here. */ static int handle_read_event_rsp(ipmi_smi_t intf, struct ipmi_smi_msg *msg) { @@ -2313,7 +2344,7 @@ static int handle_read_event_rsp(ipmi_smi_t intf, INIT_LIST_HEAD(&msgs); - spin_lock_irqsave(&(intf->events_lock), flags); + spin_lock_irqsave(&intf->events_lock, flags); spin_lock(&intf->counter_lock); intf->events++; @@ -2321,12 +2352,14 @@ static int handle_read_event_rsp(ipmi_smi_t intf, /* Allocate and fill in one message for every user that is getting events. */ - list_for_each_entry(user, &(intf->users), link) { + rcu_read_lock(); + list_for_each_entry_rcu(user, &intf->users, link) { if (! user->gets_events) continue; recv_msg = ipmi_alloc_recv_msg(); if (! recv_msg) { + rcu_read_unlock(); list_for_each_entry_safe(recv_msg, recv_msg2, &msgs, link) { list_del(&recv_msg->link); ipmi_free_recv_msg(recv_msg); @@ -2342,8 +2375,10 @@ static int handle_read_event_rsp(ipmi_smi_t intf, copy_event_into_recv_msg(recv_msg, msg); recv_msg->user = user; + kref_get(&user->refcount); list_add_tail(&(recv_msg->link), &msgs); } + rcu_read_unlock(); if (deliver_count) { /* Now deliver all the messages. */ @@ -2382,9 +2417,8 @@ static int handle_bmc_rsp(ipmi_smi_t intf, struct ipmi_smi_msg *msg) { struct ipmi_recv_msg *recv_msg; - int found = 0; - struct ipmi_user *user; unsigned long flags; + struct ipmi_user *user; recv_msg = (struct ipmi_recv_msg *) msg->user_data; if (recv_msg == NULL) @@ -2396,16 +2430,9 @@ static int handle_bmc_rsp(ipmi_smi_t intf, return 0; } + user = recv_msg->user; /* Make sure the user still exists. */ - list_for_each_entry(user, &(intf->users), link) { - if (user == recv_msg->user) { - /* Found it, so we can deliver it */ - found = 1; - break; - } - } - - if ((! found) && recv_msg->user) { + if (user && !user->valid) { /* The user for the message went away, so give up. */ spin_lock_irqsave(&intf->counter_lock, flags); intf->unhandled_local_responses++; @@ -2486,7 +2513,7 @@ static int handle_new_recv_msg(ipmi_smi_t intf, { /* It's a response to a response we sent. For this we deliver a send message response to the user. */ - struct ipmi_recv_msg *recv_msg = msg->user_data; + struct ipmi_recv_msg *recv_msg = msg->user_data; requeue = 0; if (msg->rsp_size < 2) @@ -2498,13 +2525,18 @@ static int handle_new_recv_msg(ipmi_smi_t intf, /* Invalid channel number */ goto out; - if (recv_msg) { - recv_msg->recv_type = IPMI_RESPONSE_RESPONSE_TYPE; - recv_msg->msg.data = recv_msg->msg_data; - recv_msg->msg.data_len = 1; - recv_msg->msg_data[0] = msg->rsp[2]; - deliver_response(recv_msg); - } + if (!recv_msg) + goto out; + + /* Make sure the user still exists. */ + if (!recv_msg->user || !recv_msg->user->valid) + goto out; + + recv_msg->recv_type = IPMI_RESPONSE_RESPONSE_TYPE; + recv_msg->msg.data = recv_msg->msg_data; + recv_msg->msg.data_len = 1; + recv_msg->msg_data[0] = msg->rsp[2]; + deliver_response(recv_msg); } else if ((msg->rsp[0] == ((IPMI_NETFN_APP_REQUEST|1) << 2)) && (msg->rsp[1] == IPMI_GET_MSG_CMD)) { @@ -2570,14 +2602,11 @@ void ipmi_smi_msg_received(ipmi_smi_t intf, int rv; - /* Lock the user lock so the user can't go away while we are - working on it. */ - read_lock(&(intf->users_lock)); - if ((msg->data_size >= 2) && (msg->data[0] == (IPMI_NETFN_APP_REQUEST << 2)) && (msg->data[1] == IPMI_SEND_MSG_CMD) - && (msg->user_data == NULL)) { + && (msg->user_data == NULL)) + { /* This is the local response to a command send, start the timer for these. The user_data will not be NULL if this is a response send, and we will let @@ -2612,46 +2641,46 @@ void ipmi_smi_msg_received(ipmi_smi_t intf, } ipmi_free_smi_msg(msg); - goto out_unlock; + goto out; } /* To preserve message order, if the list is not empty, we tack this message onto the end of the list. */ - spin_lock_irqsave(&(intf->waiting_msgs_lock), flags); - if (!list_empty(&(intf->waiting_msgs))) { - list_add_tail(&(msg->link), &(intf->waiting_msgs)); - spin_unlock_irqrestore(&(intf->waiting_msgs_lock), flags); - goto out_unlock; + spin_lock_irqsave(&intf->waiting_msgs_lock, flags); + if (!list_empty(&intf->waiting_msgs)) { + list_add_tail(&msg->link, &intf->waiting_msgs); + spin_unlock(&intf->waiting_msgs_lock); + goto out; } - spin_unlock_irqrestore(&(intf->waiting_msgs_lock), flags); + spin_unlock_irqrestore(&intf->waiting_msgs_lock, flags); rv = handle_new_recv_msg(intf, msg); if (rv > 0) { /* Could not handle the message now, just add it to a list to handle later. */ - spin_lock_irqsave(&(intf->waiting_msgs_lock), flags); - list_add_tail(&(msg->link), &(intf->waiting_msgs)); - spin_unlock_irqrestore(&(intf->waiting_msgs_lock), flags); + spin_lock(&intf->waiting_msgs_lock); + list_add_tail(&msg->link, &intf->waiting_msgs); + spin_unlock(&intf->waiting_msgs_lock); } else if (rv == 0) { ipmi_free_smi_msg(msg); } - out_unlock: - read_unlock(&(intf->users_lock)); + out: + return; } void ipmi_smi_watchdog_pretimeout(ipmi_smi_t intf) { ipmi_user_t user; - read_lock(&(intf->users_lock)); - list_for_each_entry(user, &(intf->users), link) { + rcu_read_lock(); + list_for_each_entry_rcu(user, &intf->users, link) { if (! user->handler->ipmi_watchdog_pretimeout) continue; user->handler->ipmi_watchdog_pretimeout(user->handler_data); } - read_unlock(&(intf->users_lock)); + rcu_read_unlock(); } static void @@ -2691,8 +2720,65 @@ smi_from_recv_msg(ipmi_smi_t intf, struct ipmi_recv_msg *recv_msg, return smi_msg; } -static void -ipmi_timeout_handler(long timeout_period) +static void check_msg_timeout(ipmi_smi_t intf, struct seq_table *ent, + struct list_head *timeouts, long timeout_period, + int slot, unsigned long *flags) +{ + struct ipmi_recv_msg *msg; + + if (!ent->inuse) + return; + + ent->timeout -= timeout_period; + if (ent->timeout > 0) + return; + + if (ent->retries_left == 0) { + /* The message has used all its retries. */ + ent->inuse = 0; + msg = ent->recv_msg; + list_add_tail(&msg->link, timeouts); + spin_lock(&intf->counter_lock); + if (ent->broadcast) + intf->timed_out_ipmb_broadcasts++; + else if (ent->recv_msg->addr.addr_type == IPMI_LAN_ADDR_TYPE) + intf->timed_out_lan_commands++; + else + intf->timed_out_ipmb_commands++; + spin_unlock(&intf->counter_lock); + } else { + struct ipmi_smi_msg *smi_msg; + /* More retries, send again. */ + + /* Start with the max timer, set to normal + timer after the message is sent. */ + ent->timeout = MAX_MSG_TIMEOUT; + ent->retries_left--; + spin_lock(&intf->counter_lock); + if (ent->recv_msg->addr.addr_type == IPMI_LAN_ADDR_TYPE) + intf->retransmitted_lan_commands++; + else + intf->retransmitted_ipmb_commands++; + spin_unlock(&intf->counter_lock); + + smi_msg = smi_from_recv_msg(intf, ent->recv_msg, slot, + ent->seqid); + if (! smi_msg) + return; + + spin_unlock_irqrestore(&intf->seq_lock, *flags); + /* Send the new message. We send with a zero + * priority. It timed out, I doubt time is + * that critical now, and high priority + * messages are really only for messages to the + * local MC, which don't get resent. */ + intf->handlers->sender(intf->send_info, + smi_msg, 0); + spin_lock_irqsave(&intf->seq_lock, *flags); + } +} + +static void ipmi_timeout_handler(long timeout_period) { ipmi_smi_t intf; struct list_head timeouts; @@ -2706,14 +2792,14 @@ ipmi_timeout_handler(long timeout_period) spin_lock(&interfaces_lock); for (i = 0; i < MAX_IPMI_INTERFACES; i++) { intf = ipmi_interfaces[i]; - if (intf == NULL) + if (IPMI_INVALID_INTERFACE(intf)) continue; - - read_lock(&(intf->users_lock)); + kref_get(&intf->refcount); + spin_unlock(&interfaces_lock); /* See if any waiting messages need to be processed. */ - spin_lock_irqsave(&(intf->waiting_msgs_lock), flags); - list_for_each_entry_safe(smi_msg, smi_msg2, &(intf->waiting_msgs), link) { + spin_lock_irqsave(&intf->waiting_msgs_lock, flags); + list_for_each_entry_safe(smi_msg, smi_msg2, &intf->waiting_msgs, link) { if (! handle_new_recv_msg(intf, smi_msg)) { list_del(&smi_msg->link); ipmi_free_smi_msg(smi_msg); @@ -2723,73 +2809,23 @@ ipmi_timeout_handler(long timeout_period) break; } } - spin_unlock_irqrestore(&(intf->waiting_msgs_lock), flags); + spin_unlock_irqrestore(&intf->waiting_msgs_lock, flags); /* Go through the seq table and find any messages that have timed out, putting them in the timeouts list. */ - spin_lock_irqsave(&(intf->seq_lock), flags); - for (j = 0; j < IPMI_IPMB_NUM_SEQ; j++) { - struct seq_table *ent = &(intf->seq_table[j]); - if (!ent->inuse) - continue; - - ent->timeout -= timeout_period; - if (ent->timeout > 0) - continue; - - if (ent->retries_left == 0) { - /* The message has used all its retries. */ - ent->inuse = 0; - msg = ent->recv_msg; - list_add_tail(&(msg->link), &timeouts); - spin_lock(&intf->counter_lock); - if (ent->broadcast) - intf->timed_out_ipmb_broadcasts++; - else if (ent->recv_msg->addr.addr_type - == IPMI_LAN_ADDR_TYPE) - intf->timed_out_lan_commands++; - else - intf->timed_out_ipmb_commands++; - spin_unlock(&intf->counter_lock); - } else { - struct ipmi_smi_msg *smi_msg; - /* More retries, send again. */ - - /* Start with the max timer, set to normal - timer after the message is sent. */ - ent->timeout = MAX_MSG_TIMEOUT; - ent->retries_left--; - spin_lock(&intf->counter_lock); - if (ent->recv_msg->addr.addr_type - == IPMI_LAN_ADDR_TYPE) - intf->retransmitted_lan_commands++; - else - intf->retransmitted_ipmb_commands++; - spin_unlock(&intf->counter_lock); - smi_msg = smi_from_recv_msg(intf, - ent->recv_msg, j, ent->seqid); - if (! smi_msg) - continue; - - spin_unlock_irqrestore(&(intf->seq_lock),flags); - /* Send the new message. We send with a zero - * priority. It timed out, I doubt time is - * that critical now, and high priority - * messages are really only for messages to the - * local MC, which don't get resent. */ - intf->handlers->sender(intf->send_info, - smi_msg, 0); - spin_lock_irqsave(&(intf->seq_lock), flags); - } - } - spin_unlock_irqrestore(&(intf->seq_lock), flags); - - list_for_each_entry_safe(msg, msg2, &timeouts, link) { + spin_lock_irqsave(&intf->seq_lock, flags); + for (j = 0; j < IPMI_IPMB_NUM_SEQ; j++) + check_msg_timeout(intf, &(intf->seq_table[j]), + &timeouts, timeout_period, j, + &flags); + spin_unlock_irqrestore(&intf->seq_lock, flags); + + list_for_each_entry_safe(msg, msg2, &timeouts, link) handle_msg_timeout(msg); - } - read_unlock(&(intf->users_lock)); + kref_put(&intf->refcount, intf_free); + spin_lock(&interfaces_lock); } spin_unlock(&interfaces_lock); } @@ -2802,7 +2838,7 @@ static void ipmi_request_event(void) spin_lock(&interfaces_lock); for (i = 0; i < MAX_IPMI_INTERFACES; i++) { intf = ipmi_interfaces[i]; - if (intf == NULL) + if (IPMI_INVALID_INTERFACE(intf)) continue; intf->handlers->request_events(intf->send_info); @@ -2884,6 +2920,13 @@ struct ipmi_recv_msg *ipmi_alloc_recv_msg(void) return rv; } +void ipmi_free_recv_msg(struct ipmi_recv_msg *msg) +{ + if (msg->user) + kref_put(&msg->user->refcount, free_user); + msg->done(msg); +} + #ifdef CONFIG_IPMI_PANIC_EVENT static void dummy_smi_done_handler(struct ipmi_smi_msg *msg) @@ -2964,7 +3007,7 @@ static void send_panic_events(char *str) /* For every registered interface, send the event. */ for (i = 0; i < MAX_IPMI_INTERFACES; i++) { intf = ipmi_interfaces[i]; - if (intf == NULL) + if (IPMI_INVALID_INTERFACE(intf)) continue; /* Send the event announcing the panic. */ @@ -2995,7 +3038,7 @@ static void send_panic_events(char *str) int j; intf = ipmi_interfaces[i]; - if (intf == NULL) + if (IPMI_INVALID_INTERFACE(intf)) continue; /* First job here is to figure out where to send the @@ -3131,7 +3174,7 @@ static int panic_event(struct notifier_block *this, /* For every registered interface, set it to run to completion. */ for (i = 0; i < MAX_IPMI_INTERFACES; i++) { intf = ipmi_interfaces[i]; - if (intf == NULL) + if (IPMI_INVALID_INTERFACE(intf)) continue; intf->handlers->set_run_to_completion(intf->send_info, 1); @@ -3160,9 +3203,8 @@ static int ipmi_init_msghandler(void) printk(KERN_INFO "ipmi message handler version " IPMI_DRIVER_VERSION "\n"); - for (i = 0; i < MAX_IPMI_INTERFACES; i++) { + for (i = 0; i < MAX_IPMI_INTERFACES; i++) ipmi_interfaces[i] = NULL; - } #ifdef CONFIG_PROC_FS proc_ipmi_root = proc_mkdir("ipmi", NULL); @@ -3258,3 +3300,4 @@ EXPORT_SYMBOL(ipmi_get_my_LUN); EXPORT_SYMBOL(ipmi_smi_add_proc_entry); EXPORT_SYMBOL(proc_ipmi_root); EXPORT_SYMBOL(ipmi_user_set_run_to_completion); +EXPORT_SYMBOL(ipmi_free_recv_msg); |