From 262bf54144ebcb78cd0d057d2705dc5fb7bba7ac Mon Sep 17 00:00:00 2001 From: "Ed L. Cashin" Date: Fri, 8 Feb 2008 04:20:03 -0800 Subject: aoe: user can ask driver to forget previously detected devices When an AoE device is detected, the kernel is informed, and a new block device is created. If the device is unused, the block device corresponding to remote device that is no longer available may be removed from the system by telling the aoe driver to "flush" its list of devices. Without this patch, software like GPFS and LVM may attempt to read from AoE devices that were discovered earlier but are no longer present, blocking until the I/O attempt times out. Signed-off-by: Ed L. Cashin Cc: Greg KH Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/block/aoe/aoedev.c | 87 ++++++++++++++++++++++++++++++++++++---------- 1 file changed, 68 insertions(+), 19 deletions(-) (limited to 'drivers/block/aoe/aoedev.c') diff --git a/drivers/block/aoe/aoedev.c b/drivers/block/aoe/aoedev.c index a4d625aefea..e26f6f4a28a 100644 --- a/drivers/block/aoe/aoedev.c +++ b/drivers/block/aoe/aoedev.c @@ -9,6 +9,10 @@ #include #include "aoe.h" +static void dummy_timer(ulong); +static void aoedev_freedev(struct aoedev *); +static void freetgt(struct aoetgt *t); + static struct aoedev *devlist; static spinlock_t devlist_lock; @@ -108,6 +112,70 @@ aoedev_downdev(struct aoedev *d) d->flags &= ~DEVFL_UP; } +static void +aoedev_freedev(struct aoedev *d) +{ + struct aoetgt **t, **e; + + if (d->gd) { + aoedisk_rm_sysfs(d); + del_gendisk(d->gd); + put_disk(d->gd); + } + t = d->targets; + e = t + NTARGETS; + for (; t < e && *t; t++) + freetgt(*t); + if (d->bufpool) + mempool_destroy(d->bufpool); + kfree(d); +} + +int +aoedev_flush(const char __user *str, size_t cnt) +{ + ulong flags; + struct aoedev *d, **dd; + struct aoedev *rmd = NULL; + char buf[16]; + int all = 0; + + if (cnt >= 3) { + if (cnt > sizeof buf) + cnt = sizeof buf; + if (copy_from_user(buf, str, cnt)) + return -EFAULT; + all = !strncmp(buf, "all", 3); + } + + flush_scheduled_work(); + spin_lock_irqsave(&devlist_lock, flags); + dd = &devlist; + while ((d = *dd)) { + spin_lock(&d->lock); + if ((!all && (d->flags & DEVFL_UP)) + || (d->flags & (DEVFL_GDALLOC|DEVFL_NEWSIZE)) + || d->nopen) { + spin_unlock(&d->lock); + dd = &d->next; + continue; + } + *dd = d->next; + aoedev_downdev(d); + d->flags |= DEVFL_TKILL; + spin_unlock(&d->lock); + d->next = rmd; + rmd = d; + } + spin_unlock_irqrestore(&devlist_lock, flags); + while ((d = rmd)) { + rmd = d->next; + del_timer_sync(&d->timer); + aoedev_freedev(d); /* must be able to sleep */ + } + return 0; +} + /* find it or malloc it */ struct aoedev * aoedev_by_sysminor_m(ulong sysminor) @@ -161,25 +229,6 @@ freetgt(struct aoetgt *t) kfree(t); } -static void -aoedev_freedev(struct aoedev *d) -{ - struct aoetgt **t, **e; - - if (d->gd) { - aoedisk_rm_sysfs(d); - del_gendisk(d->gd); - put_disk(d->gd); - } - t = d->targets; - e = t + NTARGETS; - for (; t < e && *t; t++) - freetgt(*t); - if (d->bufpool) - mempool_destroy(d->bufpool); - kfree(d); -} - void aoedev_exit(void) { -- cgit v1.2.3