dect
/
linux-2.6
Archived
13
0
Fork 0
Code Releases Activity

PCI Hotplug: serialize pci_hp_register and pci_hp_deregister 

Convert the pci_hotplug_slot_list_lock, which only protected the
list of hotplug slots, to a pci_hp_mutex which now protects both
interfaces.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This commit is contained in:
Kenji Kaneshige 2008-10-20 17:40:57 -06:00 committed by Jesse Barnes
parent 828f37683e
commit 95cb909396
1 changed files with 28 additions and 23 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

51
drivers/pci/hotplug/pci_hotplug_core.c
View File

@ -37,6 +37,7 @@
#include <linux/init.h> #include <linux/init.h>
#include <linux/mount.h> #include <linux/mount.h>
#include <linux/namei.h> #include <linux/namei.h>
#include <linux/mutex.h>
#include <linux/pci.h> #include <linux/pci.h>
#include <linux/pci_hotplug.h> #include <linux/pci_hotplug.h>
#include <asm/uaccess.h> #include <asm/uaccess.h>
@ -61,7 +62,7 @@ static int debug;
////////////////////////////////////////////////////////////////// //////////////////////////////////////////////////////////////////
static LIST_HEAD(pci_hotplug_slot_list); static LIST_HEAD(pci_hotplug_slot_list);
static DEFINE_SPINLOCK(pci_hotplug_slot_list_lock); static DEFINE_MUTEX(pci_hp_mutex);
/* these strings match up with the values in pci_bus_speed */ /* these strings match up with the values in pci_bus_speed */
static char *pci_bus_speed_strings[] = { static char *pci_bus_speed_strings[] = {
@ -530,16 +531,12 @@ static struct hotplug_slot *get_slot_from_name (const char *name)
struct hotplug_slot *slot; struct hotplug_slot *slot;
struct list_head *tmp; struct list_head *tmp;
spin_lock(&pci_hotplug_slot_list_lock);
list_for_each (tmp, &pci_hotplug_slot_list) { list_for_each (tmp, &pci_hotplug_slot_list) {
slot = list_entry (tmp, struct hotplug_slot, slot_list); slot = list_entry (tmp, struct hotplug_slot, slot_list);
if (strcmp(slot->name, name) == 0) if (strcmp(slot->name, name) == 0)
goto out; return slot;
} }
slot = NULL; return NULL;
out:
spin_unlock(&pci_hotplug_slot_list_lock);
return slot;
} }
/** /**
@ -570,9 +567,13 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr,
return -EINVAL; return -EINVAL;
} }
mutex_lock(&pci_hp_mutex);
/* Check if we have already registered a slot with the same name. */ /* Check if we have already registered a slot with the same name. */
if (get_slot_from_name(name)) if (get_slot_from_name(name)) {
return -EEXIST; result = -EEXIST;
goto out;
}
/* /*
* No problems if we call this interface from both ACPI_PCI_SLOT * No problems if we call this interface from both ACPI_PCI_SLOT
@ -580,13 +581,15 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr,
* pci_slot, the interface will simply bump the refcount. * pci_slot, the interface will simply bump the refcount.
*/ */
pci_slot = pci_create_slot(bus, slot_nr, name, slot); pci_slot = pci_create_slot(bus, slot_nr, name, slot);
if (IS_ERR(pci_slot)) if (IS_ERR(pci_slot)) {
return PTR_ERR(pci_slot); result = PTR_ERR(pci_slot);
goto cleanup;
}
if (pci_slot->hotplug) { if (pci_slot->hotplug) {
dbg("%s: already claimed\n", __func__); dbg("%s: already claimed\n", __func__);
pci_destroy_slot(pci_slot); result = -EBUSY;
return -EBUSY; goto cleanup;
} }
slot->pci_slot = pci_slot; slot->pci_slot = pci_slot;
@ -597,21 +600,21 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr,
*/ */
if (strcmp(kobject_name(&pci_slot->kobj), name)) { if (strcmp(kobject_name(&pci_slot->kobj), name)) {
result = kobject_rename(&pci_slot->kobj, name); result = kobject_rename(&pci_slot->kobj, name);
if (result) { if (result)
pci_destroy_slot(pci_slot); goto cleanup;
return result;
}
} }
spin_lock(&pci_hotplug_slot_list_lock);
list_add(&slot->slot_list, &pci_hotplug_slot_list); list_add(&slot->slot_list, &pci_hotplug_slot_list);
spin_unlock(&pci_hotplug_slot_list_lock);
result = fs_add_slot(pci_slot); result = fs_add_slot(pci_slot);
kobject_uevent(&pci_slot->kobj, KOBJ_ADD); kobject_uevent(&pci_slot->kobj, KOBJ_ADD);
dbg("Added slot %s to the list\n", name); dbg("Added slot %s to the list\n", name);
out:
mutex_unlock(&pci_hp_mutex);
return result; return result;
cleanup:
pci_destroy_slot(pci_slot);
goto out;
} }
/** /**
@ -631,13 +634,14 @@ int pci_hp_deregister(struct hotplug_slot *hotplug)
if (!hotplug) if (!hotplug)
return -ENODEV; return -ENODEV;
mutex_lock(&pci_hp_mutex);
temp = get_slot_from_name(hotplug->name); temp = get_slot_from_name(hotplug->name);
if (temp != hotplug) if (temp != hotplug) {
mutex_unlock(&pci_hp_mutex);
return -ENODEV; return -ENODEV;
}
spin_lock(&pci_hotplug_slot_list_lock);
list_del(&hotplug->slot_list); list_del(&hotplug->slot_list);
spin_unlock(&pci_hotplug_slot_list_lock);
slot = hotplug->pci_slot; slot = hotplug->pci_slot;
fs_remove_slot(slot); fs_remove_slot(slot);
@ -646,6 +650,7 @@ int pci_hp_deregister(struct hotplug_slot *hotplug)
hotplug->release(hotplug); hotplug->release(hotplug);
slot->hotplug = NULL; slot->hotplug = NULL;
pci_destroy_slot(slot); pci_destroy_slot(slot);
mutex_unlock(&pci_hp_mutex);
return 0; return 0;
} }