From aa8d7c2fbe619d8c0837296d2eaf4c14cebac198 Mon Sep 17 00:00:00 2001 From: Alasdair G Kergon Date: Fri, 6 Jan 2006 00:20:06 -0800 Subject: [PATCH] device-mapper: make lock_fs optional Devices only needs syncing when creating snapshots, so make this optional when suspending a device. Signed-off-by: Alasdair G Kergon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/md/dm.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) (limited to 'drivers/md/dm.c') diff --git a/drivers/md/dm.c b/drivers/md/dm.c index fc335e09d072..0e481512f918 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -55,6 +55,7 @@ union map_info *dm_get_mapinfo(struct bio *bio) */ #define DMF_BLOCK_IO 0 #define DMF_SUSPENDED 1 +#define DMF_FROZEN 2 struct mapped_device { struct rw_semaphore io_lock; @@ -1021,6 +1022,8 @@ static int lock_fs(struct mapped_device *md) return r; } + set_bit(DMF_FROZEN, &md->flags); + /* don't bdput right now, we don't want the bdev * to go away while it is locked. */ @@ -1029,8 +1032,12 @@ static int lock_fs(struct mapped_device *md) static void unlock_fs(struct mapped_device *md) { + if (!test_bit(DMF_FROZEN, &md->flags)) + return; + thaw_bdev(md->suspended_bdev, md->frozen_sb); md->frozen_sb = NULL; + clear_bit(DMF_FROZEN, &md->flags); } /* @@ -1040,7 +1047,7 @@ static void unlock_fs(struct mapped_device *md) * dm_bind_table, dm_suspend must be called to flush any in * flight bios and ensure that any further io gets deferred. */ -int dm_suspend(struct mapped_device *md) +int dm_suspend(struct mapped_device *md, int do_lockfs) { struct dm_table *map = NULL; DECLARE_WAITQUEUE(wait, current); @@ -1064,9 +1071,11 @@ int dm_suspend(struct mapped_device *md) } /* Flush I/O to the device. */ - r = lock_fs(md); - if (r) - goto out; + if (do_lockfs) { + r = lock_fs(md); + if (r) + goto out; + } /* * First we set the BLOCK_IO flag so no more ios will be mapped. -- cgit v1.2.2