From 3c0ee63a64a20351ed6c16ec797e1f8c850741ea Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Tue, 21 Oct 2008 13:25:28 +1100 Subject: md: use sysfs_notify_dirent to notify changes to md/dev-xxx/state The 'state' file for a device reports, for example, when the device has failed. Changes should be reported to userspace ASAP without the possibility of blocking on low-memory. sysfs_notify does have that possibility (as it takes a mutex which can be held across a kmalloc) so use sysfs_notify_dirent instead. Signed-off-by: NeilBrown --- drivers/md/md.c | 21 ++++++++++++--------- include/linux/raid/md_k.h | 3 +++ 2 files changed, 15 insertions(+), 9 deletions(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index feea72dc4b69..8b303477c77b 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -1462,6 +1462,8 @@ static int bind_rdev_to_array(mdk_rdev_t * rdev, mddev_t * mddev) kobject_del(&rdev->kobj); goto fail; } + rdev->sysfs_state = sysfs_get_dirent(rdev->kobj.sd, "state"); + list_add_rcu(&rdev->same_set, &mddev->disks); bd_claim_by_disk(rdev->bdev, rdev->bdev->bd_holder, mddev->gendisk); return 0; @@ -1491,7 +1493,8 @@ static void unbind_rdev_from_array(mdk_rdev_t * rdev) printk(KERN_INFO "md: unbind<%s>\n", bdevname(rdev->bdev,b)); rdev->mddev = NULL; sysfs_remove_link(&rdev->kobj, "block"); - + sysfs_put(rdev->sysfs_state); + rdev->sysfs_state = NULL; /* We need to delay this, otherwise we can deadlock when * writing to 'remove' to "dev/state". We also need * to delay it due to rcu usage. @@ -1926,8 +1929,8 @@ state_store(mdk_rdev_t *rdev, const char *buf, size_t len) err = 0; } - if (!err) - sysfs_notify(&rdev->kobj, NULL, "state"); + if (!err && rdev->sysfs_state) + sysfs_notify_dirent(rdev->sysfs_state); return err ? err : len; } static struct rdev_sysfs_entry rdev_state = @@ -2022,7 +2025,7 @@ slot_store(mdk_rdev_t *rdev, const char *buf, size_t len) rdev->raid_disk = -1; return err; } else - sysfs_notify(&rdev->kobj, NULL, "state"); + sysfs_notify_dirent(rdev->sysfs_state); sprintf(nm, "rd%d", rdev->raid_disk); if (sysfs_create_link(&rdev->mddev->kobj, &rdev->kobj, nm)) printk(KERN_WARNING @@ -2039,7 +2042,7 @@ slot_store(mdk_rdev_t *rdev, const char *buf, size_t len) clear_bit(Faulty, &rdev->flags); clear_bit(WriteMostly, &rdev->flags); set_bit(In_sync, &rdev->flags); - sysfs_notify(&rdev->kobj, NULL, "state"); + sysfs_notify_dirent(rdev->sysfs_state); } return len; } @@ -3583,7 +3586,7 @@ static int do_md_run(mddev_t * mddev) return -EINVAL; } } - sysfs_notify(&rdev->kobj, NULL, "state"); + sysfs_notify_dirent(rdev->sysfs_state); } md_probe(mddev->unit, NULL, NULL); @@ -4302,7 +4305,7 @@ static int add_new_disk(mddev_t * mddev, mdu_disk_info_t *info) if (err) export_rdev(rdev); else - sysfs_notify(&rdev->kobj, NULL, "state"); + sysfs_notify_dirent(rdev->sysfs_state); md_update_sb(mddev, 1); if (mddev->degraded) @@ -6113,7 +6116,7 @@ void md_check_recovery(mddev_t *mddev) rdev_for_each(rdev, rtmp, mddev) if (test_and_clear_bit(StateChanged, &rdev->flags)) - sysfs_notify(&rdev->kobj, NULL, "state"); + sysfs_notify_dirent(rdev->sysfs_state); if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) && @@ -6223,7 +6226,7 @@ void md_check_recovery(mddev_t *mddev) void md_wait_for_blocked_rdev(mdk_rdev_t *rdev, mddev_t *mddev) { - sysfs_notify(&rdev->kobj, NULL, "state"); + sysfs_notify_dirent(rdev->sysfs_state); wait_event_timeout(rdev->blocked_wait, !test_bit(Blocked, &rdev->flags), msecs_to_jiffies(5000)); diff --git a/include/linux/raid/md_k.h b/include/linux/raid/md_k.h index b16ad867e944..8fc909ef6787 100644 --- a/include/linux/raid/md_k.h +++ b/include/linux/raid/md_k.h @@ -115,6 +115,9 @@ struct mdk_rdev_s * in superblock. */ struct work_struct del_work; /* used for delayed sysfs removal */ + + struct sysfs_dirent *sysfs_state; /* handle for 'state' + * sysfs entry */ }; struct mddev_s -- cgit v1.2.3-59-g8ed1b