Chris Mason [Wed, 9 Apr 2008 20:28:12 +0000 (16:28 -0400)]
Btrfs: Do metadata checksums for reads via a workqueue
Before, metadata checksumming was done by the callers of read_tree_block,
which would set EXTENT_CSUM bits in the extent tree to show that a given
range of pages was already checksummed and didn't need to be verified
again.
But, those bits could go away via try_to_releasepage, and the end
result was bogus checksum failures on pages that never left the cache.
The new code validates checksums when the page is read. It is a little
tricky because metadata blocks can span pages and a single read may
end up going via multiple bios.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Chris Mason [Fri, 4 Apr 2008 19:40:00 +0000 (15:40 -0400)]
Btrfs: Don't allow written blocks from this transaction to be reallocated
When a block is freed, it can be immediately reused if it is from
the current transaction. But, an extra check is required to make sure
the block had not been written yet. If it were reused after being written,
the transid in the block header might match the transid of the
next time the block was allocated.
The parent node records the transaction ID of the block it is pointing to,
and this is used as part of validating the block on reads. So, there
can only be one version of a block per transaction.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Chris Mason [Tue, 1 Apr 2008 17:48:14 +0000 (13:48 -0400)]
Btrfs: Verify checksums on tree blocks found without read_tree_block
Checksums were only verified by btrfs_read_tree_block, which meant the
functions to probe the page cache for blocks were not validating checksums.
Normally this is fine because the buffers will only be in cache if they
have already been validated.
But, there is a window while the buffer is being read from disk where
it could be up to date in the cache but not yet verified. This patch
makes sure all buffers go through checksum verification before they
are used.
This is safer, and it prevents modification of buffers before they go
through the csum code.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Chris Mason [Tue, 1 Apr 2008 15:26:07 +0000 (11:26 -0400)]
Btrfs: Keep fs_mutex during reads done by snapshot deletion
There was an optimization to drop the fs_mutex when doing snapshot deletion
reads, but this can lead to false positives on checksumming errors. Keep
the lock for now.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Chris Mason [Tue, 1 Apr 2008 15:21:32 +0000 (11:21 -0400)]
Reorder the flags field in struct btrfs_header and record a flag on writeout
This allows detection of blocks that have already been written in the
running transaction so they can be recowed instead of modified again.
It is step one in trusting the transid field of the block pointers.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Greg KH [Wed, 20 Feb 2008 19:14:16 +0000 (14:14 -0500)]
btrfs: fixes for kobject changes in mainline
Here's a patch against the unstable tree that gets the code to build
against Linus's current tree (2.6.24-git12). This is needed as the
kobject/kset api has changed there.
I tried to make the smallest changes needed, and it builds and loads
successfully, but I don't have a btrfs volume anywhere (yet) to try to
see if things still work properly :)
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Chris Mason <chris.mason@oracle.com>
Chris Mason [Wed, 20 Feb 2008 17:07:25 +0000 (12:07 -0500)]
Btrfs: checksum file data at bio submission time instead of during writepage
When we checkum file data during writepage, the checksumming is done one
page at a time, making it difficult to do bulk metadata modifications
to insert checksums for large ranges of the file at once.
This patch changes btrfs to checksum on a per-bio basis instead. The
bios are checksummed before they are handed off to the block layer, so
each bio is contiguous and only has pages from the same inode.
Checksumming on a bio basis allows us to insert and modify the file
checksum items in large groups. It also allows the checksumming to
be done more easily by async worker threads.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
David Miller [Fri, 15 Feb 2008 15:40:52 +0000 (10:40 -0500)]
Btrfs: unaligned access fixes
Btrfs set/get macros lose type information needed to avoid
unaligned accesses on sparc64.
ere is a patch for the kernel bits which fixes most of the
unaligned accesses on sparc64.
btrfs_name_hash is modified to return the hash value instead
of getting a return location via a (potentially unaligned)
pointer.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Yan [Fri, 1 Feb 2008 19:58:07 +0000 (14:58 -0500)]
Call btrfs_cow_block while lowering tree level.
When freeing root block of a tree, btrfs_free_extent' parameter
'ref_generation' is from root block itseft. When freeing non-root
block, 'ref_generation' is from its parent. so when converting a
non-root block to root block, we must guarantee its generation is
equal to its parent's generation.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Yan [Wed, 30 Jan 2008 19:39:54 +0000 (14:39 -0500)]
btrfs_drop_extent fixe for inline items > 8K
When truncating a inline extent, btrfs_drop_extents doesn't properly
handle the case "key.offset > inline_limit". This bug can only happen
when max line size is larger than 8K.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Chris Mason [Tue, 29 Jan 2008 14:59:12 +0000 (09:59 -0500)]
Btrfs: extent_io and extent_state optimizations
The end_bio routines are changed to take a pointer to the extent state
struct, and the state tree is walked in order to set/clear appropriate
bits as IO completes. This greatly reduces the number of rbtree searches
done by the end_bio handlers, and reduces lock contention.
The extent_io releasepage function is changed to avoid expensive searches
for locked state.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Chris Mason [Thu, 24 Jan 2008 21:13:08 +0000 (16:13 -0500)]
Btrfs: Split the extent_map code into two parts
There is now extent_map for mapping offsets in the file to disk and
extent_io for state tracking, IO submission and extent_bufers.
The new extent_map code shifts from [start,end] pairs to [start,len], and
pushes the locking out into the caller. This allows a few performance
optimizations and is easier to use.
A number of extent_map usage bugs were fixed, mostly with failing
to remove extent_map entries when changing the file.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Yan [Tue, 22 Jan 2008 17:46:56 +0000 (12:46 -0500)]
Fix for btrfs_find_free_objectid
btrfs_find_free_objectid may return a used objectid due to arithmetic
underflow. This bug may happen when parameter 'root' is tree root, so
it may cause serious problems when creating snapshot or sub-volume.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
projects / linux-beck.git / log