When writing into preallocated regions there is a case where XFS can oops
or hang doing the unwritten extent conversion on I/O completion. It turns
out that the problem is related to the btree cursor being invalid.
When we do an insert into the tree, we may need to split blocks in the
tree. When we only split at the leaf level (i.e. level 0), everything
works just fine. However, if we have a multi-level split in the btreee,
the cursor passed to the insert function is no longer valid once the
insert is complete.
The leaf level split is handled correctly because all the operations at
level 0 are done using the original cursor, hence it is updated correctly.
However, when we need to update the next level up the tree, we don't use
that cursor - we use a cloned cursor that points to the index in the next
level up where we need to do the insert.
Hence if we need to split a second level, the changes to the tree are
reflected in the cloned cursor and not the original cursor. This
clone-and-move-up-a-level-on-split behaviour recurses all the way to the
top of the tree.
The complexity here is that these cloned cursors do not point to the
original index that was inserted - they point to the newly allocated block
(the right block) and the original cursor pointer to that level may still
point to the left block. Hence, without deep examination of the cloned
cursor and buffers, we cannot update the original cursor with the new path
from the cloned cursor.
In these cases the original cursor could be pointing to the wrong block(s)
and hence a subsequent modification to the tree using that cursor will
lead to corruption of the tree.
The crash case occurs when the tree changes height - we insert a new level
in the tree, and the cursor does not have a buffer in it's path for that
level. Hence any attempt to walk back up the cursor to the root block will
result in a null pointer dereference.
To make matters even more complex, the BMAP BT is rooted in an inode, so
we can have a change of height in the btree *without a root split*. That
is, if the root block in the inode is full when we split a leaf node, we
cannot fit the pointer to the new block in the root, so we allocate a new
block, migrate all the ptrs out of the inode into the new block and point
the inode root block at the newly allocated block. This changes the height
of the tree without a root split having occurred and hence invalidates the
path in the original cursor.
The patch below prevents xfs_bmbt_insert() from returning with an invalid
cursor by detecting the cases that invalidate the original cursor and
refresh it by do a lookup into the btree for the original index we were
inserting at.
Note that the INOBT, AGFBNO and AGFCNT btree implementations also have
this bug, but the cursor is currently always destroyed or revalidated
after an insert for those trees. Hence this patch only address the problem
in the BMBT code.
SGI-PV: 979339
SGI-Modid: xfs-linux-melb:xfs-kern:30701a
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
remove beX_add functions and replace all uses with beX_add_cpu
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Reviewed-by: Dave Chinner <dgc@sgi.com>
Cc: Timothy Shimmin <tes@sgi.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use XFS_IS_REALTIME_INODE in more places, and #define it to 0 if
CONFIG_XFS_RT is off. This should be safe because mount checks in
xfs_rtmount_init:
so if we get mounted w/o CONFIG_XFS_RT, no realtime inodes should be
encountered after that.
Defining XFS_IS_REALTIME_INODE to 0 saves a bit of stack space,
presumeably gcc can optimize around the various "if (0)" type checks:
xfs_alloc_file_space -8 xfs_bmap_adjacent -16 xfs_bmapi -8
xfs_bmap_rtalloc -16 xfs_bunmapi -28 xfs_free_file_space -64 xfs_imap +8
<-- ? hmm. xfs_iomap_write_direct -12 xfs_qm_dqusage_adjust -4
xfs_qm_vop_chown_reserve -4
SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:30014a
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
In sgi mod# xfs-linux-melb:xfs-kern:29319a, the variable renaming was not
complete and variable 'b' was left unchanged for non-lbd 32 bit machines.
SGI-PV: 968563
SGI-Modid: xfs-linux-melb:xfs-kern:29469a
Signed-off-by: Michal Piotrowski <michal.k.k.piotrowski@gmail.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
xfs_bmbt_set_all/xfs_bmbt_disk_set_all are identical to
xfs_bmbt_set_allf/xfs_bmbt_disk_set_allf except that the former take a
xfs_bmbt_irec_t and the latter take the individual extent fields as scalar
values.
This patch reimplements xfs_bmbt_set_all/xfs_bmbt_disk_set_all as trivial
wrappers around xfs_bmbt_set_allf/xfs_bmbt_disk_set_allf and cleans up the
variable naming in xfs_bmbt_set_allf/xfs_bmbt_disk_set_allf to have some
meaning instead of one char variable names.
SGI-PV: 968563
SGI-Modid: xfs-linux-melb:xfs-kern:29319a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
currently xfs_bmbt_rec_t is used both for ondisk extents as well as
host-endian ones. This patch adds a new xfs_bmbt_rec_host_t for the native
endian ones and cleans up the fallout. There have been various endianess
issues in the tracing / debug printf code that are fixed by this patch.
SGI-PV: 968563
SGI-Modid: xfs-linux-melb:xfs-kern:29318a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
Remove the hardcoded "fnames" for tracing, and just embed them in tracing
macros via __FUNCTION__. Kills a lot of #ifdefs too.
SGI-PV: 967353
SGI-Modid: xfs-linux-melb:xfs-kern:29099a
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
Patch provided by Eric Sandeen (sandeen@sandeen.net).
SGI-PV: 960897
SGI-Modid: xfs-linux-melb:xfs-kern:28038a
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
It makes it incrementally clearer to read the code when the top of a macro
spaghetti-pile only receives the 3 arguments it uses, rather than 2 extra
ones which are not used. Also when you start pulling this thread out of
the sweater (i.e. remove unused args from XFS_BTREE_*_ADDR), a couple
other third arms etc fall off too. If they're not used in the macro, then
they sometimes don't need to be passed to the function calling the macro
either, etc....
Patch provided by Eric Sandeen (sandeen@sandeen.net).
SGI-PV: 960197
SGI-Modid: xfs-linux-melb:xfs-kern:28037a
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
gcc-4.1 and more recent aggressively inline static functions which
increases XFS stack usage by ~15% in critical paths. Prevent this from
occurring by adding noinline to the STATIC definition.
Also uninline some functions that are too large to be inlined and were
causing problems with CONFIG_FORCED_INLINING=y.
Finally, clean up all the different users of inline, __inline and
__inline__ and put them under one STATIC_INLINE macro. For debug kernels
the STATIC_INLINE macro uninlines those functions.
SGI-PV: 957159
SGI-Modid: xfs-linux-melb:xfs-kern:27585a
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: David Chatterton <chatz@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
__be64 and let the callers use the proper macros.
SGI-PV: 954580
SGI-Modid: xfs-linux-melb:xfs-kern:26560a
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nathan Scott <nathans@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
transaction within each such operation may involve multiple locking of AGF
buffer. While the freeing extent function has sorted the extents based on
AGF number before entering into transaction, however, when the file system
space is very limited, the allocation of space would try every AGF to get
space allocated, this could potentially cause out-of-order locking, thus
deadlock could happen. This fix mitigates the scarce space for allocation
by setting aside a few blocks without reservation, and avoid deadlock by
maintaining ascending order of AGF locking.
SGI-PV: 947395
SGI-Modid: xfs-linux-melb:xfs-kern:210801a
Signed-off-by: Yingping Lu <yingping@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
code to prepare for an upcoming mod which will introduce multi-level
in-core extent allocations. Although the in-core extent management is
using a new code path in this mod, the functionality remains the same.
Major changes include: - Introduce 10 new subroutines which re-orgainze
the existing code but do NOT change functionality:
xfs_iext_get_ext() xfs_iext_insert() xfs_iext_add()
xfs_iext_remove() xfs_iext_remove_inline()
xfs_iext_remove_direct() xfs_iext_realloc_direct()
xfs_iext_direct_to_inline() xfs_iext_inline_to_direct()
xfs_iext_destroy() - Remove 2 subroutines (functionality moved to new
subroutines above): xfs_iext_realloc() -replaced by xfs_iext_add()
and xfs_iext_remove() xfs_bmap_insert_exlist() - replaced by
xfs_iext_insert() xfs_bmap_delete_exlist() - replaced by
xfs_iext_remove() - Replace all hard-coded (indexed) extent assignments
with a call to xfs_iext_get_ext() - Replace all extent record pointer
arithmetic (ep++, ep--, base + lastx,..) with calls to
xfs_iext_get_ext() - Update comments to remove the idea of a single
"extent list" and introduce "extent record" terminology instead
SGI-PV: 928864
SGI-Modid: xfs-linux-melb:xfs-kern:207390a
Signed-off-by: Mandy Kirkconnell <alkirkco@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Harvey Harrison