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authorAlasdair G Kergon <agk@redhat.com>2006-01-06 00:20:06 -0800
committerLinus Torvalds <torvalds@g5.osdl.org>2006-01-06 08:34:01 -0800
commitaa8d7c2fbe619d8c0837296d2eaf4c14cebac198 (patch)
tree88b63e397b0c2dbdf2b8feb3920d565d352412d6 /drivers/md/dm.c
parente39e2e95eb8bd536b61654e8fda1516d0a6a3cd1 (diff)
[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 <agk@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'drivers/md/dm.c')
-rw-r--r--drivers/md/dm.c17
1 files changed, 13 insertions, 4 deletions
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.