From d1782a3b0a15d9ac497a8f47931c4536bfe8d18e Mon Sep 17 00:00:00 2001 From: Alasdair G Kergon Date: Thu, 5 May 2005 16:16:03 -0700 Subject: [PATCH] device-mapper: store bdev while frozen Store the struct block_device while device is frozen, saving us one call to bdget_disk(). Signed-Off-By: Alasdair G Kergon From: Christoph Hellwig Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/md/dm.c | 23 ++++++++--------------- 1 file changed, 8 insertions(+), 15 deletions(-) (limited to 'drivers/md/dm.c') diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 243ff6884e83..ea180af6d227 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -97,6 +97,7 @@ struct mapped_device { * freeze/thaw support require holding onto a super block */ struct super_block *frozen_sb; + struct block_device *frozen_bdev; }; #define MIN_IOS 256 @@ -990,19 +991,17 @@ int dm_swap_table(struct mapped_device *md, struct dm_table *table) */ static int __lock_fs(struct mapped_device *md) { - struct block_device *bdev; - if (test_and_set_bit(DMF_FS_LOCKED, &md->flags)) return 0; - bdev = bdget_disk(md->disk, 0); - if (!bdev) { + md->frozen_bdev = bdget_disk(md->disk, 0); + if (!md->frozen_bdev) { DMWARN("bdget failed in __lock_fs"); return -ENOMEM; } WARN_ON(md->frozen_sb); - md->frozen_sb = freeze_bdev(bdev); + md->frozen_sb = freeze_bdev(md->frozen_bdev); /* don't bdput right now, we don't want the bdev * to go away while it is locked. We'll bdput * in __unlock_fs @@ -1012,21 +1011,15 @@ static int __lock_fs(struct mapped_device *md) static int __unlock_fs(struct mapped_device *md) { - struct block_device *bdev; - if (!test_and_clear_bit(DMF_FS_LOCKED, &md->flags)) return 0; - bdev = bdget_disk(md->disk, 0); - if (!bdev) { - DMWARN("bdget failed in __unlock_fs"); - return -ENOMEM; - } + thaw_bdev(md->frozen_bdev, md->frozen_sb); + bdput(md->frozen_bdev); - thaw_bdev(bdev, md->frozen_sb); md->frozen_sb = NULL; - bdput(bdev); - bdput(bdev); + md->frozen_bdev = NULL; + return 0; } -- cgit v1.2.2 From 3dcee8064bd36c547b45514dfd33df4c12695428 Mon Sep 17 00:00:00 2001 From: Alasdair G Kergon Date: Thu, 5 May 2005 16:16:04 -0700 Subject: [PATCH] device-mapper: __unlock_fs void Make __unlock_fs() void. From: Christoph Hellwig Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/md/dm.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) (limited to 'drivers/md/dm.c') diff --git a/drivers/md/dm.c b/drivers/md/dm.c index ea180af6d227..0e4c8d3ca9fb 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1009,18 +1009,16 @@ static int __lock_fs(struct mapped_device *md) return 0; } -static int __unlock_fs(struct mapped_device *md) +static void __unlock_fs(struct mapped_device *md) { if (!test_and_clear_bit(DMF_FS_LOCKED, &md->flags)) - return 0; + return; thaw_bdev(md->frozen_bdev, md->frozen_sb); bdput(md->frozen_bdev); md->frozen_sb = NULL; md->frozen_bdev = NULL; - - return 0; } /* -- cgit v1.2.2 From dfbe03f6d09fcebf85ae2a2cbb4ceee9b0985e67 Mon Sep 17 00:00:00 2001 From: Alasdair G Kergon Date: Thu, 5 May 2005 16:16:04 -0700 Subject: [PATCH] device-mapper: let freeze_bdev return error Allow freeze_bdev() to return an error. Signed-Off-By: Alasdair G Kergon From: Christoph Hellwig Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/md/dm.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) (limited to 'drivers/md/dm.c') diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 0e4c8d3ca9fb..9687a084b5ff 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -991,22 +991,38 @@ int dm_swap_table(struct mapped_device *md, struct dm_table *table) */ static int __lock_fs(struct mapped_device *md) { + int error = -ENOMEM; + if (test_and_set_bit(DMF_FS_LOCKED, &md->flags)) return 0; md->frozen_bdev = bdget_disk(md->disk, 0); if (!md->frozen_bdev) { DMWARN("bdget failed in __lock_fs"); - return -ENOMEM; + goto out; } WARN_ON(md->frozen_sb); + md->frozen_sb = freeze_bdev(md->frozen_bdev); + if (IS_ERR(md->frozen_sb)) { + error = PTR_ERR(md->frozen_sb); + goto out_bdput; + } + /* don't bdput right now, we don't want the bdev * to go away while it is locked. We'll bdput * in __unlock_fs */ return 0; + +out_bdput: + bdput(md->frozen_bdev); + md->frozen_sb = NULL; + md->frozen_bdev = NULL; +out: + clear_bit(DMF_FS_LOCKED, &md->flags); + return error; } static void __unlock_fs(struct mapped_device *md) -- cgit v1.2.2 From 354e007121de546e50b5592c2557575117435522 Mon Sep 17 00:00:00 2001 From: Alasdair G Kergon Date: Thu, 5 May 2005 16:16:05 -0700 Subject: [PATCH] device-mapper: handle __lock_fs error Handle error from __lock_fs() Signed-Off-By: Alasdair G Kergon From: Christoph Hellwig Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/md/dm.c | 22 ++++++++++++++-------- 1 file changed, 14 insertions(+), 8 deletions(-) (limited to 'drivers/md/dm.c') diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 9687a084b5ff..83f53a46c2d4 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1048,6 +1048,7 @@ int dm_suspend(struct mapped_device *md) { struct dm_table *map; DECLARE_WAITQUEUE(wait, current); + int error; /* Flush I/O to the device. */ down_read(&md->lock); @@ -1056,25 +1057,29 @@ int dm_suspend(struct mapped_device *md) return -EINVAL; } + error = __lock_fs(md); + if (error) { + up_read(&md->lock); + return error; + } + map = dm_get_table(md); if (map) dm_table_presuspend_targets(map); - __lock_fs(md); up_read(&md->lock); /* - * First we set the BLOCK_IO flag so no more ios will be - * mapped. + * First we set the BLOCK_IO flag so no more ios will be mapped. + * + * If the flag is already set we know another thread is trying to + * suspend as well, so we leave the fs locked for this thread. */ down_write(&md->lock); if (test_bit(DMF_BLOCK_IO, &md->flags)) { - /* - * If we get here we know another thread is - * trying to suspend as well, so we leave the fs - * locked for this thread. - */ up_write(&md->lock); + if (map) + dm_table_put(map); return -EINVAL; } @@ -1107,6 +1112,7 @@ int dm_suspend(struct mapped_device *md) /* were we interrupted ? */ if (atomic_read(&md->pending)) { + /* FIXME Undo the presuspend_targets */ __unlock_fs(md); clear_bit(DMF_BLOCK_IO, &md->flags); up_write(&md->lock); -- cgit v1.2.2 From b84b0287a8ba618568a8bc9ac8847ac332abe90d Mon Sep 17 00:00:00 2001 From: Alasdair G Kergon Date: Thu, 5 May 2005 16:16:06 -0700 Subject: [PATCH] device-mapper: tidy dm_suspend Tidy dm_suspend. Signed-Off-By: Alasdair G Kergon From: Christoph Hellwig Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/md/dm.c | 43 +++++++++++++++++++++++-------------------- 1 file changed, 23 insertions(+), 20 deletions(-) (limited to 'drivers/md/dm.c') diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 83f53a46c2d4..f6b03957efc7 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1048,20 +1048,16 @@ int dm_suspend(struct mapped_device *md) { struct dm_table *map; DECLARE_WAITQUEUE(wait, current); - int error; + int error = -EINVAL; /* Flush I/O to the device. */ down_read(&md->lock); - if (test_bit(DMF_BLOCK_IO, &md->flags)) { - up_read(&md->lock); - return -EINVAL; - } + if (test_bit(DMF_BLOCK_IO, &md->flags)) + goto out_read_unlock; error = __lock_fs(md); - if (error) { - up_read(&md->lock); - return error; - } + if (error) + goto out_read_unlock; map = dm_get_table(md); if (map) @@ -1075,15 +1071,14 @@ int dm_suspend(struct mapped_device *md) * If the flag is already set we know another thread is trying to * suspend as well, so we leave the fs locked for this thread. */ + error = -EINVAL; down_write(&md->lock); - if (test_bit(DMF_BLOCK_IO, &md->flags)) { - up_write(&md->lock); + if (test_and_set_bit(DMF_BLOCK_IO, &md->flags)) { if (map) dm_table_put(map); - return -EINVAL; + goto out_write_unlock; } - set_bit(DMF_BLOCK_IO, &md->flags); add_wait_queue(&md->wait, &wait); up_write(&md->lock); @@ -1111,13 +1106,9 @@ int dm_suspend(struct mapped_device *md) remove_wait_queue(&md->wait, &wait); /* were we interrupted ? */ - if (atomic_read(&md->pending)) { - /* FIXME Undo the presuspend_targets */ - __unlock_fs(md); - clear_bit(DMF_BLOCK_IO, &md->flags); - up_write(&md->lock); - return -EINTR; - } + error = -EINTR; + if (atomic_read(&md->pending)) + goto out_unfreeze; set_bit(DMF_SUSPENDED, &md->flags); @@ -1128,6 +1119,18 @@ int dm_suspend(struct mapped_device *md) up_write(&md->lock); return 0; + +out_unfreeze: + /* FIXME Undo dm_table_presuspend_targets */ + __unlock_fs(md); + clear_bit(DMF_BLOCK_IO, &md->flags); +out_write_unlock: + up_write(&md->lock); + return error; + +out_read_unlock: + up_read(&md->lock); + return error; } int dm_resume(struct mapped_device *md) -- cgit v1.2.2