[PATCH] IPMI: Allow hot system interface remove
This modifies the IPMI driver so that a lower-level interface can be
dynamically removed while in use so it can support hot-removal of hardware.
It also adds the ability to specify and dynamically change the IPMI interface
the watchdog timer and the poweroff code use.
Signed-off-by: Corey Minyard <minyard@acm.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/char/ipmi/ipmi_poweroff.c b/drivers/char/ipmi/ipmi_poweroff.c
index 8d941db..85f8071 100644
--- a/drivers/char/ipmi/ipmi_poweroff.c
+++ b/drivers/char/ipmi/ipmi_poweroff.c
@@ -43,6 +43,9 @@
#define PFX "IPMI poweroff: "
+static void ipmi_po_smi_gone(int if_num);
+static void ipmi_po_new_smi(int if_num, struct device *device);
+
/* Definitions for controlling power off (if the system supports it). It
* conveniently matches the IPMI chassis control values. */
#define IPMI_CHASSIS_POWER_DOWN 0 /* power down, the default. */
@@ -51,6 +54,37 @@
/* the IPMI data command */
static int poweroff_powercycle;
+/* Which interface to use, -1 means the first we see. */
+static int ifnum_to_use = -1;
+
+/* Our local state. */
+static int ready = 0;
+static ipmi_user_t ipmi_user;
+static int ipmi_ifnum;
+static void (*specific_poweroff_func)(ipmi_user_t user) = NULL;
+
+/* Holds the old poweroff function so we can restore it on removal. */
+static void (*old_poweroff_func)(void);
+
+static int set_param_ifnum(const char *val, struct kernel_param *kp)
+{
+ int rv = param_set_int(val, kp);
+ if (rv)
+ return rv;
+ if ((ifnum_to_use < 0) || (ifnum_to_use == ipmi_ifnum))
+ return 0;
+
+ ipmi_po_smi_gone(ipmi_ifnum);
+ ipmi_po_new_smi(ifnum_to_use, NULL);
+ return 0;
+}
+
+module_param_call(ifnum_to_use, set_param_ifnum, param_get_int,
+ &ifnum_to_use, 0644);
+MODULE_PARM_DESC(ifnum_to_use, "The interface number to use for the watchdog "
+ "timer. Setting to -1 defaults to the first registered "
+ "interface");
+
/* parameter definition to allow user to flag power cycle */
module_param(poweroff_powercycle, int, 0644);
MODULE_PARM_DESC(poweroff_powercycle, " Set to non-zero to enable power cycle instead of power down. Power cycle is contingent on hardware support, otherwise it defaults back to power down.");
@@ -440,15 +474,6 @@
/ sizeof(struct poweroff_function))
-/* Our local state. */
-static int ready = 0;
-static ipmi_user_t ipmi_user;
-static void (*specific_poweroff_func)(ipmi_user_t user) = NULL;
-
-/* Holds the old poweroff function so we can restore it on removal. */
-static void (*old_poweroff_func)(void);
-
-
/* Called on a powerdown request. */
static void ipmi_poweroff_function (void)
{
@@ -473,6 +498,9 @@
if (ready)
return;
+ if ((ifnum_to_use >= 0) && (ifnum_to_use != if_num))
+ return;
+
rv = ipmi_create_user(if_num, &ipmi_poweroff_handler, NULL,
&ipmi_user);
if (rv) {
@@ -481,6 +509,8 @@
return;
}
+ ipmi_ifnum = if_num;
+
/*
* Do a get device ide and store some results, since this is
* used by several functions.
@@ -541,9 +571,15 @@
static void ipmi_po_smi_gone(int if_num)
{
- /* This can never be called, because once poweroff driver is
- registered, the interface can't go away until the power
- driver is unregistered. */
+ if (!ready)
+ return;
+
+ if (ipmi_ifnum != if_num)
+ return;
+
+ ready = 0;
+ ipmi_destroy_user(ipmi_user);
+ pm_power_off = old_poweroff_func;
}
static struct ipmi_smi_watcher smi_watcher =