linux-stable.git/drivers/md/persistent-data, branch linux-3.8.y

dm thin: fix discard corruption

2013-03-28T19:17:48+00:00

commit f046f89a99ccfd9408b94c653374ff3065c7edb3 upstream.

Fix a bug in dm_btree_remove that could leave leaf values with incorrect
reference counts.  The effect of this was that removal of a shared block
could result in the space maps thinking the block was no longer used.
More concretely, if you have a thin device and a snapshot of it, sending
a discard to a shared region of the thin could corrupt the snapshot.

Thinp uses a 2-level nested btree to store it's mappings.  This first
level is indexed by thin device, and the second level by logical
block.

Often when we're removing an entry in this mapping tree we need to
rebalance nodes, which can involve shadowing them, possibly creating a
copy if the block is shared.  If we do create a copy then children of
that node need to have their reference counts incremented.  In this
way reference counts percolate down the tree as shared trees diverge.

The rebalance functions were incrementing the children at the
appropriate time, but they were always assuming the children were
internal nodes.  This meant the leaf values (in our case packed
block/flags entries) were not being incremented.

Signed-off-by: Joe Thornber 
Signed-off-by: Alasdair G Kergon 
Signed-off-by: Greg Kroah-Hartman

Merge tag 'dm-3.8-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm

2012-12-22T01:08:06+00:00

Pull dm update from Alasdair G Kergon:
 "Miscellaneous device-mapper fixes, cleanups and performance
  improvements.

  Of particular note:
   - Disable broken WRITE SAME support in all targets except linear and
     striped.  Use it when kcopyd is zeroing blocks.
   - Remove several mempools from targets by moving the data into the
     bio's new front_pad area(which dm calls 'per_bio_data').
   - Fix a race in thin provisioning if discards are misused.
   - Prevent userspace from interfering with the ioctl parameters and
     use kmalloc for the data buffer if it's small instead of vmalloc.
   - Throttle some annoying error messages when I/O fails."

* tag 'dm-3.8-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm: (36 commits)
  dm stripe: add WRITE SAME support
  dm: remove map_info
  dm snapshot: do not use map_context
  dm thin: dont use map_context
  dm raid1: dont use map_context
  dm flakey: dont use map_context
  dm raid1: rename read_record to bio_record
  dm: move target request nr to dm_target_io
  dm snapshot: use per_bio_data
  dm verity: use per_bio_data
  dm raid1: use per_bio_data
  dm: introduce per_bio_data
  dm kcopyd: add WRITE SAME support to dm_kcopyd_zero
  dm linear: add WRITE SAME support
  dm: add WRITE SAME support
  dm: prepare to support WRITE SAME
  dm ioctl: use kmalloc if possible
  dm ioctl: remove PF_MEMALLOC
  dm persistent data: improve improve space map block alloc failure message
  dm thin: use DMERR_LIMIT for errors
  ...

dm persistent data: improve improve space map block alloc failure message

2012-12-21T20:23:36+00:00

Improve space map error message when unable to allocate a new
metadata block.

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

dm persistent data: use DMERR_LIMIT for errors

2012-12-21T20:23:34+00:00

Nearly all of persistent-data is in the IO path so throttle error
messages with DMERR_LIMIT to limit the amount logged when
something has gone wrong.

Signed-off-by: Mike Snitzer 
Signed-off-by: Alasdair G Kergon

dm block manager: reinstate message when validator fails

2012-12-21T20:23:34+00:00

Reinstate a useful error message when the block manager buffer validator fails.
This was mistakenly eliminated when the block manager was converted to use
dm-bufio.

Signed-off-by: Mike Snitzer 
Signed-off-by: Alasdair G Kergon

dm persistent data: fix nested btree deletion

2012-12-21T20:23:32+00:00

When deleting nested btrees, the code forgets to delete the innermost
btree.  The thin-metadata code serendipitously compensates for this by
claiming there is one extra layer in the tree.

This patch corrects both problems.

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

dm persistent data: rename node to btree_node

2012-12-21T20:23:30+00:00

This patch fixes a compilation failure on sparc32 by renaming struct node.

struct node is already defined in include/linux/node.h. On sparc32, it
happens to be included through other dependencies and persistent-data
doesn't compile because of conflicting declarations.

Signed-off-by: Mikulas Patocka 
Cc: stable@vger.kernel.org
Signed-off-by: Alasdair G Kergon

md: Fix typo in drivers/md

2012-10-29T21:57:50+00:00

Correct spelling typo in drivers/md.

Signed-off-by: Masanari Iida 
Signed-off-by: Jiri Kosina

dm persistent data: convert to use le32_add_cpu

2012-10-12T15:59:47+00:00

Convert cpu_to_le32(le32_to_cpu(E1) + E2) to use le32_add_cpu().

dpatch engine is used to auto generate this patch.
(https://github.com/weiyj/dpatch)

Signed-off-by: Wei Yongjun 
Signed-off-by: Alasdair G Kergon

dm persistent data: introduce dm_bm_set_read_only

2012-07-27T14:08:15+00:00

Introduce dm_bm_set_read_only to switch the block manager into a
read-only mode.  To be used when dm-thin degrades due to io errors on
the metadata device.

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