[PATCH] ipmi: add power cycle capability

This patch to adds "power cycle" functionality to the IPMI power off module
ipmi_poweroff.  It also contains changes to support procfs control of the
feature.

The power cycle action is considered an optional chassis control in the IPMI
specification.  However, it is definitely useful when the hardware supports
it.  A power cycle is usually required in order to reset a firmware in a bad
state.  This action is critical to allow remote management of servers.

The implementation adds power cycle as optional to the ipmi_poweroff module.
It can be modified dynamically through the proc entry mentioned above.  During
a power down and enabled, the power cycle command is sent to the BMC firmware.
 If it fails either due to non-support or some error, it will retry to send
the command as power off.

Signed-off-by: Christopher A. Poblete <Chris_Poblete@dell.com>
Signed-off-by: Corey Minyard <minyard@acm.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 27 insertions, 2 deletions

diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c
index ed75e96d0035..1813d0d198f1 100644
--- a/drivers/char/ipmi/ipmi_msghandler.c
+++ b/drivers/char/ipmi/ipmi_msghandler.c
@@ -54,7 +54,9 @@ static int ipmi_init_msghandler(void);
 
 static int initialized = 0;
 
-static struct proc_dir_entry *proc_ipmi_root = NULL;
+#ifdef CONFIG_PROC_FS
+struct proc_dir_entry *proc_ipmi_root = NULL;
+#endif /* CONFIG_PROC_FS */
 
 #define MAX_EVENTS_IN_QUEUE     25
 
@@ -124,11 +126,13 @@ struct ipmi_channel
         unsigned char protocol;
 };
 
+#ifdef CONFIG_PROC_FS
 struct ipmi_proc_entry
 {
         char                   *name;
         struct ipmi_proc_entry *next;
 };
+#endif
 
 #define IPMI_IPMB_NUM_SEQ       64
 #define IPMI_MAX_CHANNELS       8
@@ -156,10 +160,13 @@ struct ipmi_smi
         struct ipmi_smi_handlers *handlers;
         void                     *send_info;
 
+#ifdef CONFIG_PROC_FS
         /* A list of proc entries for this interface.  This does not
            need a lock, only one thread creates it and only one thread
            destroys it. */
+        spinlock_t             proc_entry_lock;
         struct ipmi_proc_entry *proc_entries;
+#endif
 
         /* A table of sequence numbers for this interface.  We use the
            sequence numbers for IPMB messages that go out of the
@@ -1470,8 +1477,9 @@ int ipmi_smi_add_proc_entry(ipmi_smi_t smi, char *name,
                             read_proc_t *read_proc, write_proc_t *write_proc,
                             void *data, struct module *owner)
 {
-        struct proc_dir_entry  *file;
         int                    rv = 0;
+#ifdef CONFIG_PROC_FS
+        struct proc_dir_entry  *file;
         struct ipmi_proc_entry *entry;
 
         /* Create a list element. */
@@ -1497,10 +1505,13 @@ int ipmi_smi_add_proc_entry(ipmi_smi_t smi, char *name,
                 file->write_proc = write_proc;
                 file->owner = owner;
 
+                spin_lock(&smi->proc_entry_lock);
                 /* Stick it on the list. */
                 entry->next = smi->proc_entries;
                 smi->proc_entries = entry;
+                spin_unlock(&smi->proc_entry_lock);
         }
+#endif /* CONFIG_PROC_FS */
 
         return rv;
 }
@@ -1509,6 +1520,7 @@ static int add_proc_entries(ipmi_smi_t smi, int num)
 {
         int rv = 0;
 
+#ifdef CONFIG_PROC_FS
         sprintf(smi->proc_dir_name, "%d", num);
         smi->proc_dir = proc_mkdir(smi->proc_dir_name, proc_ipmi_root);
         if (!smi->proc_dir)
@@ -1531,14 +1543,17 @@ static int add_proc_entries(ipmi_smi_t smi, int num)
                 rv = ipmi_smi_add_proc_entry(smi, "version",
                                              version_file_read_proc, NULL,
                                              smi, THIS_MODULE);
+#endif /* CONFIG_PROC_FS */
 
         return rv;
 }
 
 static void remove_proc_entries(ipmi_smi_t smi)
 {
+#ifdef CONFIG_PROC_FS
         struct ipmi_proc_entry *entry;
 
+        spin_lock(&smi->proc_entry_lock);
         while (smi->proc_entries) {
                 entry = smi->proc_entries;
                 smi->proc_entries = entry->next;
@@ -1547,7 +1562,9 @@ static void remove_proc_entries(ipmi_smi_t smi)
                 kfree(entry->name);
                 kfree(entry);
         }
+        spin_unlock(&smi->proc_entry_lock);
         remove_proc_entry(smi->proc_dir_name, proc_ipmi_root);
+#endif /* CONFIG_PROC_FS */
 }
 
 static int
@@ -1694,6 +1711,9 @@ int ipmi_register_smi(struct ipmi_smi_handlers *handlers,
                                 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));
@@ -3085,6 +3105,7 @@ static int ipmi_init_msghandler(void)
                 ipmi_interfaces[i] = NULL;
         }
 
+#ifdef CONFIG_PROC_FS
         proc_ipmi_root = proc_mkdir("ipmi", NULL);
         if (!proc_ipmi_root) {
             printk(KERN_ERR PFX "Unable to create IPMI proc dir");
@@ -3092,6 +3113,7 @@ static int ipmi_init_msghandler(void)
         }
 
         proc_ipmi_root->owner = THIS_MODULE;
+#endif /* CONFIG_PROC_FS */
 
         init_timer(&ipmi_timer);
         ipmi_timer.data = 0;
@@ -3129,7 +3151,9 @@ static __exit void cleanup_ipmi(void)
         atomic_inc(&stop_operation);
         del_timer_sync(&ipmi_timer);
 
+#ifdef CONFIG_PROC_FS
         remove_proc_entry(proc_ipmi_root->name, &proc_root);
+#endif /* CONFIG_PROC_FS */
 
         initialized = 0;
 
@@ -3170,4 +3194,5 @@ EXPORT_SYMBOL(ipmi_get_my_address);
 EXPORT_SYMBOL(ipmi_set_my_LUN);
 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);