From aa8d7c2fbe619d8c0837296d2eaf4c14cebac198 Mon Sep 17 00:00:00 2001 From: Alasdair G Kergon Date: Fri, 6 Jan 2006 00:20:06 -0800 Subject: [PATCH] [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-ioctl.c | 4 ++-- drivers/md/dm.c | 17 +++++++++++++---- drivers/md/dm.h | 2 +- 3 files changed, 16 insertions(+), 7 deletions(-) diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c index 3e327db..dbc07af 100644 --- a/drivers/md/dm-ioctl.c +++ b/drivers/md/dm-ioctl.c @@ -700,7 +700,7 @@ static int do_suspend(struct dm_ioctl *param) return -ENXIO; if (!dm_suspended(md)) - r = dm_suspend(md); + r = dm_suspend(md, 1); if (!r) r = __dev_status(md, param); @@ -738,7 +738,7 @@ static int do_resume(struct dm_ioctl *param) if (new_map) { /* Suspend if it isn't already suspended */ if (!dm_suspended(md)) - dm_suspend(md); + dm_suspend(md, 1); r = dm_swap_table(md, new_map); if (r) { diff --git a/drivers/md/dm.c b/drivers/md/dm.c index fc335e0..0e48151 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. diff --git a/drivers/md/dm.h b/drivers/md/dm.h index 95a0cfb..4eaf075 100644 --- a/drivers/md/dm.h +++ b/drivers/md/dm.h @@ -69,7 +69,7 @@ void dm_put(struct mapped_device *md); /* * A device can still be used while suspended, but I/O is deferred. */ -int dm_suspend(struct mapped_device *md); +int dm_suspend(struct mapped_device *md, int with_lockfs); int dm_resume(struct mapped_device *md); /* -- 2.7.4