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author | Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> | 2012-06-20 12:52:57 -0700 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-07-16 09:03:51 -0700 |
commit | 615fb8b018599cfe16b466b1a1c98cf1c3ecaf0e (patch) | |
tree | 6fcd1e66ea44c39f678743441c97a2c41b9a2e6b /Documentation/PCI/00-INDEX | |
parent | a4ab3b05fe0320bad00a1ba320d6fd4b9cd29643 (diff) |
nilfs2: ensure proper cache clearing for gc-inodes
commit fbb24a3a915f105016f1c828476be11aceac8504 upstream.
A gc-inode is a pseudo inode used to buffer the blocks to be moved by
garbage collection.
Block caches of gc-inodes must be cleared every time a garbage collection
function (nilfs_clean_segments) completes. Otherwise, stale blocks
buffered in the caches may be wrongly reused in successive calls of the GC
function.
For user files, this is not a problem because their gc-inodes are
distinguished by a checkpoint number as well as an inode number. They
never buffer different blocks if either an inode number, a checkpoint
number, or a block offset differs.
However, gc-inodes of sufile, cpfile and DAT file can store different data
for the same block offset. Thus, the nilfs_clean_segments function can
move incorrect block for these meta-data files if an old block is cached.
I found this is really causing meta-data corruption in nilfs.
This fixes the issue by ensuring cache clear of gc-inodes and resolves
reported GC problems including checkpoint file corruption, b-tree
corruption, and the following warning during GC.
nilfs_palloc_freev: entry number 307234 already freed.
...
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Tested-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'Documentation/PCI/00-INDEX')
0 files changed, 0 insertions, 0 deletions