diff options
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/ipmi/ipmi_msghandler.c | 210 |
1 files changed, 97 insertions, 113 deletions
diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c index da13df4..761ed26 100644 --- a/drivers/char/ipmi/ipmi_msghandler.c +++ b/drivers/char/ipmi/ipmi_msghandler.c @@ -193,6 +193,9 @@ struct ipmi_smi struct kref refcount; + /* Used for a list of interfaces. */ + struct list_head link; + /* The list of upper layers that are using me. seq_lock * protects this. */ struct list_head users; @@ -338,13 +341,6 @@ struct ipmi_smi }; #define to_si_intf_from_dev(device) container_of(device, struct ipmi_smi, dev) -/* 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)) - /** * The driver model view of the IPMI messaging driver. */ @@ -354,11 +350,8 @@ static struct device_driver ipmidriver = { }; static DEFINE_MUTEX(ipmidriver_mutex); -#define MAX_IPMI_INTERFACES 4 -static ipmi_smi_t ipmi_interfaces[MAX_IPMI_INTERFACES]; - -/* Directly protects the ipmi_interfaces data structure. */ -static DEFINE_SPINLOCK(interfaces_lock); +static struct list_head ipmi_interfaces = LIST_HEAD_INIT(ipmi_interfaces); +static DEFINE_MUTEX(ipmi_interfaces_mutex); /* List of watchers that want to know when smi's are added and deleted. */ @@ -423,25 +416,50 @@ static void intf_free(struct kref *ref) kfree(intf); } +struct watcher_entry { + struct list_head link; + int intf_num; +}; + int ipmi_smi_watcher_register(struct ipmi_smi_watcher *watcher) { - int i; - unsigned long flags; + ipmi_smi_t intf; + struct list_head to_deliver = LIST_HEAD_INIT(to_deliver); + struct watcher_entry *e, *e2; + + mutex_lock(&ipmi_interfaces_mutex); + + list_for_each_entry_rcu(intf, &ipmi_interfaces, link) { + if (intf->intf_num == -1) + continue; + e = kmalloc(sizeof(*e), GFP_KERNEL); + if (!e) + goto out_err; + e->intf_num = intf->intf_num; + list_add_tail(&e->link, &to_deliver); + } 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++) { - ipmi_smi_t intf = ipmi_interfaces[i]; - if (IPMI_INVALID_INTERFACE(intf)) - continue; - spin_unlock_irqrestore(&interfaces_lock, flags); - watcher->new_smi(i, intf->si_dev); - spin_lock_irqsave(&interfaces_lock, flags); + + mutex_unlock(&ipmi_interfaces_mutex); + + list_for_each_entry_safe(e, e2, &to_deliver, link) { + list_del(&e->link); + watcher->new_smi(e->intf_num, intf->si_dev); + kfree(e); } - spin_unlock_irqrestore(&interfaces_lock, flags); + + return 0; + + out_err: + list_for_each_entry_safe(e, e2, &to_deliver, link) { + list_del(&e->link); + kfree(e); + } + return -ENOMEM; } int ipmi_smi_watcher_unregister(struct ipmi_smi_watcher *watcher) @@ -776,17 +794,19 @@ int ipmi_create_user(unsigned int if_num, if (!new_user) return -ENOMEM; - 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); - rv = -EINVAL; - goto out_kfree; + rcu_read_lock(); + list_for_each_entry_rcu(intf, &ipmi_interfaces, link) { + if (intf->intf_num == if_num) + goto found; } + rcu_read_unlock(); + rv = -EINVAL; + goto out_kfree; + found: /* Note that each existing user holds a refcount to the interface. */ kref_get(&intf->refcount); - spin_unlock_irqrestore(&interfaces_lock, flags); + rcu_read_unlock(); kref_init(&new_user->refcount); new_user->handler = handler; @@ -2449,9 +2469,10 @@ int ipmi_register_smi(struct ipmi_smi_handlers *handlers, int i, j; int rv; ipmi_smi_t intf; - unsigned long flags; + ipmi_smi_t tintf; int version_major; int version_minor; + struct list_head *link; version_major = ipmi_version_major(device_id); version_minor = ipmi_version_minor(device_id); @@ -2477,7 +2498,7 @@ int ipmi_register_smi(struct ipmi_smi_handlers *handlers, kfree(intf); return -ENOMEM; } - intf->intf_num = -1; + intf->intf_num = -1; /* Mark it invalid for now. */ kref_init(&intf->refcount); intf->bmc->id = *device_id; intf->si_dev = si_dev; @@ -2511,20 +2532,22 @@ int ipmi_register_smi(struct ipmi_smi_handlers *handlers, spin_lock_init(&intf->counter_lock); intf->proc_dir = NULL; - rv = -ENOMEM; - spin_lock_irqsave(&interfaces_lock, flags); - for (i = 0; i < MAX_IPMI_INTERFACES; i++) { - if (ipmi_interfaces[i] == NULL) { - intf->intf_num = i; - /* Reserve the entry till we are done. */ - ipmi_interfaces[i] = IPMI_INVALID_INTERFACE_ENTRY; - rv = 0; + mutex_lock(&ipmi_interfaces_mutex); + /* Look for a hole in the numbers. */ + i = 0; + link = &ipmi_interfaces; + list_for_each_entry_rcu(tintf, &ipmi_interfaces, link) { + if (tintf->intf_num != i) { + link = &tintf->link; break; } + i++; } - spin_unlock_irqrestore(&interfaces_lock, flags); - if (rv) - goto out; + /* Add the new interface in numeric order. */ + if (i == 0) + list_add_rcu(&intf->link, &ipmi_interfaces); + else + list_add_tail_rcu(&intf->link, link); rv = handlers->start_processing(send_info, intf); if (rv) @@ -2562,16 +2585,14 @@ int ipmi_register_smi(struct ipmi_smi_handlers *handlers, if (rv) { if (intf->proc_dir) remove_proc_entries(intf); + list_del_rcu(&intf->link); + mutex_unlock(&ipmi_interfaces_mutex); + synchronize_rcu(); 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); + /* After this point the interface is legal to use. */ + intf->intf_num = i; + mutex_unlock(&ipmi_interfaces_mutex); call_smi_watchers(i, intf->si_dev); } @@ -2580,26 +2601,14 @@ int ipmi_register_smi(struct ipmi_smi_handlers *handlers, int ipmi_unregister_smi(ipmi_smi_t intf) { - int i; struct ipmi_smi_watcher *w; - unsigned long flags; ipmi_bmc_unregister(intf); - 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; - } - } - spin_unlock_irqrestore(&interfaces_lock,flags); - - if (i == MAX_IPMI_INTERFACES) - return -ENODEV; + mutex_lock(&ipmi_interfaces_mutex); + list_del_rcu(&intf->link); + mutex_unlock(&ipmi_interfaces_mutex); + synchronize_rcu(); remove_proc_entries(intf); @@ -2607,14 +2616,9 @@ int ipmi_unregister_smi(ipmi_smi_t intf) an interface is gone. */ down_read(&smi_watchers_sem); list_for_each_entry(w, &smi_watchers, link) - w->smi_gone(i); + w->smi_gone(intf->intf_num); up_read(&smi_watchers_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; } @@ -3446,18 +3450,12 @@ static void ipmi_timeout_handler(long timeout_period) struct ipmi_recv_msg *msg, *msg2; struct ipmi_smi_msg *smi_msg, *smi_msg2; unsigned long flags; - int i, j; + int i; INIT_LIST_HEAD(&timeouts); - spin_lock(&interfaces_lock); - for (i = 0; i < MAX_IPMI_INTERFACES; i++) { - intf = ipmi_interfaces[i]; - if (IPMI_INVALID_INTERFACE(intf)) - continue; - kref_get(&intf->refcount); - spin_unlock(&interfaces_lock); - + rcu_read_lock(); + list_for_each_entry_rcu(intf, &ipmi_interfaces, link) { /* 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, @@ -3477,35 +3475,26 @@ static void ipmi_timeout_handler(long timeout_period) 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++) - check_msg_timeout(intf, &(intf->seq_table[j]), - &timeouts, timeout_period, j, + for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++) + check_msg_timeout(intf, &(intf->seq_table[i]), + &timeouts, timeout_period, i, &flags); spin_unlock_irqrestore(&intf->seq_lock, flags); list_for_each_entry_safe(msg, msg2, &timeouts, link) handle_msg_timeout(msg); - - kref_put(&intf->refcount, intf_free); - spin_lock(&interfaces_lock); } - spin_unlock(&interfaces_lock); + rcu_read_unlock(); } static void ipmi_request_event(void) { ipmi_smi_t intf; - int i; - - spin_lock(&interfaces_lock); - for (i = 0; i < MAX_IPMI_INTERFACES; i++) { - intf = ipmi_interfaces[i]; - if (IPMI_INVALID_INTERFACE(intf)) - continue; + rcu_read_lock(); + list_for_each_entry_rcu(intf, &ipmi_interfaces, link) intf->handlers->request_events(intf->send_info); - } - spin_unlock(&interfaces_lock); + rcu_read_unlock(); } static struct timer_list ipmi_timer; @@ -3634,7 +3623,6 @@ static void send_panic_events(char *str) struct kernel_ipmi_msg msg; ipmi_smi_t intf; unsigned char data[16]; - int i; struct ipmi_system_interface_addr *si; struct ipmi_addr addr; struct ipmi_smi_msg smi_msg; @@ -3668,9 +3656,9 @@ static void send_panic_events(char *str) recv_msg.done = dummy_recv_done_handler; /* For every registered interface, send the event. */ - for (i = 0; i < MAX_IPMI_INTERFACES; i++) { - intf = ipmi_interfaces[i]; - if (IPMI_INVALID_INTERFACE(intf)) + list_for_each_entry_rcu(intf, &ipmi_interfaces, link) { + if (intf->intf_num == -1) + /* Interface was not ready yet. */ continue; /* Send the event announcing the panic. */ @@ -3695,13 +3683,14 @@ static void send_panic_events(char *str) if (!str) return; - for (i = 0; i < MAX_IPMI_INTERFACES; i++) { + /* For every registered interface, send the event. */ + list_for_each_entry_rcu(intf, &ipmi_interfaces, link) { char *p = str; struct ipmi_ipmb_addr *ipmb; int j; - intf = ipmi_interfaces[i]; - if (IPMI_INVALID_INTERFACE(intf)) + if (intf->intf_num == -1) + /* Interface was not ready yet. */ continue; /* First job here is to figure out where to send the @@ -3827,7 +3816,6 @@ static int panic_event(struct notifier_block *this, unsigned long event, void *ptr) { - int i; ipmi_smi_t intf; if (has_panicked) @@ -3835,9 +3823,9 @@ static int panic_event(struct notifier_block *this, has_panicked = 1; /* For every registered interface, set it to run to completion. */ - for (i = 0; i < MAX_IPMI_INTERFACES; i++) { - intf = ipmi_interfaces[i]; - if (IPMI_INVALID_INTERFACE(intf)) + list_for_each_entry_rcu(intf, &ipmi_interfaces, link) { + if (intf->intf_num == -1) + /* Interface was not ready yet. */ continue; intf->handlers->set_run_to_completion(intf->send_info, 1); @@ -3858,7 +3846,6 @@ static struct notifier_block panic_block = { static int ipmi_init_msghandler(void) { - int i; int rv; if (initialized) @@ -3873,9 +3860,6 @@ 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++) - ipmi_interfaces[i] = NULL; - #ifdef CONFIG_PROC_FS proc_ipmi_root = proc_mkdir("ipmi", NULL); if (!proc_ipmi_root) { |
