From 637842cfdbe2b981f7088f7633e630570f58efaf Mon Sep 17 00:00:00 2001 From: David Teigland Date: Fri, 6 Jan 2006 00:20:00 -0800 Subject: [PATCH] device-mapper: add dm_find_md Abstract dm_find_md() from dm_get_mdptr() to allow use elsewhere. Signed-off-by: Alasdair G Kergon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/md/dm.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) (limited to 'drivers/md/dm.c') diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 930b9fc2795..27cd234cf68 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -902,10 +902,9 @@ int dm_create_with_minor(unsigned int minor, struct mapped_device **result) return create_aux(minor, 1, result); } -void *dm_get_mdptr(dev_t dev) +static struct mapped_device *dm_find_md(dev_t dev) { struct mapped_device *md; - void *mdptr = NULL; unsigned minor = MINOR(dev); if (MAJOR(dev) != _major || minor >= (1 << MINORBITS)) @@ -914,12 +913,22 @@ void *dm_get_mdptr(dev_t dev) down(&_minor_lock); md = idr_find(&_minor_idr, minor); - - if (md && (dm_disk(md)->first_minor == minor)) - mdptr = md->interface_ptr; + if (!md || (dm_disk(md)->first_minor != minor)) + md = NULL; up(&_minor_lock); + return md; +} + +void *dm_get_mdptr(dev_t dev) +{ + struct mapped_device *md; + void *mdptr = NULL; + + md = dm_find_md(dev); + if (md) + mdptr = md->interface_ptr; return mdptr; } -- cgit v1.2.3-70-g09d2 From d229a9589ff3b988d3f999cdcfa350f97a372673 Mon Sep 17 00:00:00 2001 From: David Teigland Date: Fri, 6 Jan 2006 00:20:01 -0800 Subject: [PATCH] device-mapper: add dm_get_md Add dm_get_dev() to get a mapped device given its dev_t. Signed-off-by: Alasdair G Kergon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/md/dm.c | 10 ++++++++++ drivers/md/dm.h | 1 + 2 files changed, 11 insertions(+) (limited to 'drivers/md/dm.c') diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 27cd234cf68..9e8c1edd89d 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -921,6 +921,16 @@ static struct mapped_device *dm_find_md(dev_t dev) return md; } +struct mapped_device *dm_get_md(dev_t dev) +{ + struct mapped_device *md = dm_find_md(dev); + + if (md) + dm_get(md); + + return md; +} + void *dm_get_mdptr(dev_t dev) { struct mapped_device *md; diff --git a/drivers/md/dm.h b/drivers/md/dm.h index e38c3fc1a1d..ab078a24939 100644 --- a/drivers/md/dm.h +++ b/drivers/md/dm.h @@ -58,6 +58,7 @@ int dm_create(struct mapped_device **md); int dm_create_with_minor(unsigned int minor, struct mapped_device **md); void dm_set_mdptr(struct mapped_device *md, void *ptr); void *dm_get_mdptr(dev_t dev); +struct mapped_device *dm_get_md(dev_t dev); /* * Reference counting for md. -- cgit v1.2.3-70-g09d2 From e39e2e95eb8bd536b61654e8fda1516d0a6a3cd1 Mon Sep 17 00:00:00 2001 From: Alasdair G Kergon Date: Fri, 6 Jan 2006 00:20:05 -0800 Subject: [PATCH] device-mapper: rename frozen_bdev Rename frozen_bdev to suspended_bdev and move the bdget outside lockfs. (This prepares for making lockfs optional.) Signed-off-by: Alasdair G Kergon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/md/dm.c | 51 +++++++++++++++++++++++++-------------------------- 1 file changed, 25 insertions(+), 26 deletions(-) (limited to 'drivers/md/dm.c') diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 9e8c1edd89d..fc335e09d07 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -97,7 +97,7 @@ struct mapped_device { * freeze/thaw support require holding onto a super block */ struct super_block *frozen_sb; - struct block_device *frozen_bdev; + struct block_device *suspended_bdev; }; #define MIN_IOS 256 @@ -836,9 +836,9 @@ static void __set_size(struct mapped_device *md, sector_t size) { set_capacity(md->disk, size); - down(&md->frozen_bdev->bd_inode->i_sem); - i_size_write(md->frozen_bdev->bd_inode, (loff_t)size << SECTOR_SHIFT); - up(&md->frozen_bdev->bd_inode->i_sem); + down(&md->suspended_bdev->bd_inode->i_sem); + i_size_write(md->suspended_bdev->bd_inode, (loff_t)size << SECTOR_SHIFT); + up(&md->suspended_bdev->bd_inode->i_sem); } static int __bind(struct mapped_device *md, struct dm_table *t) @@ -1010,43 +1010,27 @@ out: */ static int lock_fs(struct mapped_device *md) { - int r = -ENOMEM; - - md->frozen_bdev = bdget_disk(md->disk, 0); - if (!md->frozen_bdev) { - DMWARN("bdget failed in lock_fs"); - goto out; - } + int r; WARN_ON(md->frozen_sb); - md->frozen_sb = freeze_bdev(md->frozen_bdev); + md->frozen_sb = freeze_bdev(md->suspended_bdev); if (IS_ERR(md->frozen_sb)) { r = PTR_ERR(md->frozen_sb); - goto out_bdput; + md->frozen_sb = NULL; + return r; } /* don't bdput right now, we don't want the bdev - * to go away while it is locked. We'll bdput - * in unlock_fs + * to go away while it is locked. */ return 0; - -out_bdput: - bdput(md->frozen_bdev); - md->frozen_sb = NULL; - md->frozen_bdev = NULL; -out: - return r; } static void unlock_fs(struct mapped_device *md) { - thaw_bdev(md->frozen_bdev, md->frozen_sb); - bdput(md->frozen_bdev); - + thaw_bdev(md->suspended_bdev, md->frozen_sb); md->frozen_sb = NULL; - md->frozen_bdev = NULL; } /* @@ -1072,6 +1056,13 @@ int dm_suspend(struct mapped_device *md) /* This does not get reverted if there's an error later. */ dm_table_presuspend_targets(map); + md->suspended_bdev = bdget_disk(md->disk, 0); + if (!md->suspended_bdev) { + DMWARN("bdget failed in dm_suspend"); + r = -ENOMEM; + goto out; + } + /* Flush I/O to the device. */ r = lock_fs(md); if (r) @@ -1124,6 +1115,11 @@ int dm_suspend(struct mapped_device *md) r = 0; out: + if (r && md->suspended_bdev) { + bdput(md->suspended_bdev); + md->suspended_bdev = NULL; + } + dm_table_put(map); up(&md->suspend_lock); return r; @@ -1154,6 +1150,9 @@ int dm_resume(struct mapped_device *md) unlock_fs(md); + bdput(md->suspended_bdev); + md->suspended_bdev = NULL; + clear_bit(DMF_SUSPENDED, &md->flags); dm_table_unplug_all(map); -- cgit v1.2.3-70-g09d2 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-ioctl.c | 4 ++-- drivers/md/dm.c | 17 +++++++++++++---- drivers/md/dm.h | 2 +- 3 files changed, 16 insertions(+), 7 deletions(-) (limited to 'drivers/md/dm.c') diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c index 3e327db5731..dbc07afd446 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 fc335e09d07..0e481512f91 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 95a0cfbe5b4..4eaf075da21 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); /* -- cgit v1.2.3-70-g09d2