linux.git/drivers/md, branch v3.10-rc2

dm thin: fix metadata dev resize detection

2013-05-19T17:57:50+00:00

Fix detection of the need to resize the dm thin metadata device.

The code incorrectly tried to extend the metadata device when it
didn't need to due to a merging error with patch 24347e9 ("dm thin:
detect metadata device resizing").

  device-mapper: transaction manager: couldn't open metadata space map
  device-mapper: thin metadata: tm_open_with_sm failed
  device-mapper: thin: aborting transaction failed
  device-mapper: thin: switching pool to failure mode

Signed-off-by: Alasdair G Kergon

dm cache: set config value

2013-05-10T13:37:21+00:00

Share configuration option processing code between the dm cache
ctr and message functions.

Signed-off-by: Joe Thornber 
Signed-off-by: Alasdair G Kergon

dm cache: move config fns

2013-05-10T13:37:21+00:00

Move process_config_option() in dm-cache-target.c to make the
next patch more readable.

Signed-off-by: Alasdair G Kergon

dm thin: generate event when metadata threshold passed

2013-05-10T13:37:21+00:00

Generate a dm event when the amount of remaining thin pool metadata
space falls below a certain level.

The threshold is taken to be a quarter of the size of the metadata
device with a minimum threshold of 4MB.

Signed-off-by: Joe Thornber 
Signed-off-by: Alasdair G Kergon

dm persistent metadata: add space map threshold callback

2013-05-10T13:37:20+00:00

Add a threshold callback to dm persistent data space maps.

Signed-off-by: Joe Thornber 
Signed-off-by: Alasdair G Kergon

dm persistent data: add threshold callback to space map

2013-05-10T13:37:20+00:00

Add a threshold callback function to the persistent data space map
interface for a subsequent patch to use.

dm-thin and dm-cache are interested in knowing when they're getting
low on metadata or data blocks.  This patch introduces a new method
for registering a callback against a threshold.

Signed-off-by: Joe Thornber 
Signed-off-by: Alasdair G Kergon

dm thin: detect metadata device resizing

2013-05-10T13:37:19+00:00

Allow the dm thin pool metadata device to be extended.

Whenever a pool is resumed, detect whether the size of the metadata
device has increased, and if so, extend the metadata to use the new
space.

Signed-off-by: Joe Thornber 
Signed-off-by: Alasdair G Kergon

dm persistent data: support space map resizing

2013-05-10T13:37:19+00:00

Support extending a dm persistent data metadata space map.

The extend itself is implemented by switching back to the boostrap
allocator and pointing to the new space.  The extra bitmap indexes are
then allocated from the new space, and finally we switch back to the
proper space map ops and tweak the reference counts.

Signed-off-by: Joe Thornber 
Signed-off-by: Alasdair G Kergon

dm thin: open dev read only when possible

2013-05-10T13:37:19+00:00

If a thin pool is created in read-only-metadata mode then only open the
metadata device read-only.

Previously it was always opened with FMODE_READ | FMODE_WRITE.

(Note that dm_get_device() still allows read-only dm devices to be used
read-write at the moment: If I create a read-only linear device for the
metadata, via dmsetup load --readonly, then I can still create a rw pool
out of it.)

Signed-off-by: Joe Thornber 
Signed-off-by: Alasdair G Kergon

dm thin: refactor data dev resize

2013-05-10T13:37:18+00:00

Refactor device size functions in preparation for similar metadata
device resizing functions.

Signed-off-by: Joe Thornber 
Signed-off-by: Alasdair G Kergon