The brelse() function tests whether its argument is NULL
and then returns immediately.
Thus remove the tests which are not needed around the shown calls.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/0d713702-072f-a89c-20ec-ca70aa83a432@web.de
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Fix the bug when calculating the physical block number of the first
block in the split extent.
This bug will cause xfstests shared/298 failure on ext4 with bigalloc
enabled occasionally. Ext4 error messages indicate that previously freed
blocks are being freed again, and the following fsck will fail due to
the inconsistency of block bitmap and bg descriptor.
The following is an example case:
1. First, Initialize a ext4 filesystem with cluster size '16K', block size
'4K', in which case, one cluster contains four blocks.
2. Create one file (e.g., xxx.img) on this ext4 filesystem. Now the extent
tree of this file is like:
...
36864:[0]4:220160
36868:[0]14332:145408
51200:[0]2:231424
...
3. Then execute PUNCH_HOLE fallocate on this file. The hole range is
like:
..
ext4_ext_remove_space: dev 254,16 ino 12 since 49506 end 49506 depth 1
ext4_ext_remove_space: dev 254,16 ino 12 since 49544 end 49546 depth 1
ext4_ext_remove_space: dev 254,16 ino 12 since 49605 end 49607 depth 1
...
4. Then the extent tree of this file after punching is like
...
49507:[0]37:158047
49547:[0]58:158087
...
5. Detailed procedure of punching hole [49544, 49546]
5.1. The block address space:
```
lblk ~49505 49506 49507~49543 49544~49546 49547~
---------+------+-------------+----------------+--------
extent | hole | extent | hole | extent
---------+------+-------------+----------------+--------
pblk ~158045 158046 158047~158083 158084~158086 158087~
```
5.2. The detailed layout of cluster 39521:
```
cluster 39521
<------------------------------->
hole extent
<----------------------><--------
lblk 49544 49545 49546 49547
+-------+-------+-------+-------+
| | | | |
+-------+-------+-------+-------+
pblk 158084 1580845 158086 158087
```
5.3. The ftrace output when punching hole [49544, 49546]:
- ext4_ext_remove_space (start 49544, end 49546)
- ext4_ext_rm_leaf (start 49544, end 49546, last_extent [49507(158047), 40], partial [pclu 39522 lblk 0 state 2])
- ext4_remove_blocks (extent [49507(158047), 40], from 49544 to 49546, partial [pclu 39522 lblk 0 state 2]
- ext4_free_blocks: (block 158084 count 4)
- ext4_mballoc_free (extent 1/6753/1)
5.4. Ext4 error message in dmesg:
EXT4-fs error (device vdb): mb_free_blocks:1457: group 1, block 158084:freeing already freed block (bit 6753); block bitmap corrupt.
EXT4-fs error (device vdb): ext4_mb_generate_buddy:747: group 1, block bitmap and bg descriptor inconsistent: 19550 vs 19551 free clusters
In this case, the whole cluster 39521 is freed mistakenly when freeing
pblock 158084~158086 (i.e., the first three blocks of this cluster),
although pblock 158087 (the last remaining block of this cluster) has
not been freed yet.
The root cause of this isuue is that, the pclu of the partial cluster is
calculated mistakenly in ext4_ext_remove_space(). The correct
partial_cluster.pclu (i.e., the cluster number of the first block in the
next extent, that is, lblock 49597 (pblock 158086)) should be 39521 rather
than 39522.
Fixes: f4226d9ea4 ("ext4: fix partial cluster initialization")
Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Eric Whitney <enwlinux@gmail.com>
Cc: stable@kernel.org # v3.19+
Link: https://lore.kernel.org/r/1590121124-37096-1-git-send-email-jefflexu@linux.alibaba.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
By moving FIEMAP_FLAG_SYNC handling to fiemap_prep we ensure it is
handled once instead of duplicated, but can still be done under fs locks,
like xfs/iomap intended with its duplicate handling. Also make sure the
error value of filemap_write_and_wait is propagated to user space.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Link: https://lore.kernel.org/r/20200523073016.2944131-8-hch@lst.de
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Replace fiemap_check_flags with a fiemap_prep helper that also takes the
inode and mapped range, and performs the sanity check and truncation
previously done in fiemap_check_range. This way the validation is inside
the file system itself and thus properly works for the stacked overlayfs
case as well.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Link: https://lore.kernel.org/r/20200523073016.2944131-7-hch@lst.de
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
iomap_fiemap already calls fiemap_check_flags first thing, so this
additional check is redundant.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200523073016.2944131-3-hch@lst.de
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The fiemap and EXT4_IOC_GET_ES_CACHE cases share almost no code, so split
them into entirely separate functions.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200523073016.2944131-2-hch@lst.de
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Add an extra validation of the len parameter, as for ext4 some files
might have smaller file size limits than others. This also means the
redundant size check in ext4_ioctl_get_es_cache can go away, as all
size checking is done in the shared fiemap handler.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200505154324.3226743-3-hch@lst.de
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The path performing block allocations in ext4_ext_map_blocks() contains
code trimming the length of a new extent that is repeated later
in the function. This code is both redundant and unnecessary as the
exact length of the new extent has already been calculated. Rewrite the
instantiation of the map struct in this case to use the available
values, avoiding the overhead of unnecessary conversions and improving
clarity. Add another map struct instantiation tailored specifically to
the separate case for an existing written extent. Remove an old comment
that no longer appears applicable to the current code.
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Link: https://lore.kernel.org/r/20200510155805.18808-1-enwlinux@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
ext_debug() msgs could be helpful, provided those could be enabled
without recompiling kernel and also if we could selectively enable
only required prints for case by case debugging.
So make ext_debug() implementation use pr_debug().
Also change ext_debug() to be defined with CONFIG_EXT4_DEBUG.
So EXT_DEBUG macro now mostly remain for below 3 functions.
ext4_ext_show_path/leaf/move() (whose print msgs use ext_debug()
which again could be dynamically enabled using pr_debug())
This also changes the ext_debug() to take inode as a parameter
to add inode no. in all of it's msgs.
Prints additional info like process name / pid, superblock id etc.
This also removes any explicit function names passed in ext_debug().
Since ext_debug() on it's own prints file, func and line no.
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/d31dc189b0aeda9384fe7665e36da7cd8c61571f.1589086800.git.riteshh@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
ext4_map_blocks() has ext_debug msg early at the start of function.
We also get ext_debug msg if we could allocate a block from
ext4_ext_map_blocks(). But there is no ext_debug() msg in case of
block allocation failure. So add one along with error code.
Also add more info in ext_debug() msg like how many blocks were allocated
v/s how many were requested in ext4_ext_map_blocks().
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/1610ec2aa932396be00f9d552fe29da473ead176.1589086800.git.riteshh@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
We can't fail in the truncate path without requiring an fsck.
Add work around for this by using a combination of retry loops
and the __GFP_NOFAIL flag.
From: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Anna Pendleton <pendleton@google.com>
Reviewed-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20200507175028.15061-1-pendleton@google.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
If ext4_ext_convert_to_initialized() fails when called within
ext4_ext_handle_unwritten_extents(), immediately error out through the
exit point at function end. Fix the error handling in the event
ext4_ext_convert_to_initialized() returns 0, which it shouldn't do when
converting an existing extent. The current code returns the passed in
value of allocated (which is likely non-zero) while failing to set
m_flags, m_pblk, and m_len.
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Link: https://lore.kernel.org/r/20200430185320.23001-5-enwlinux@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
If the call to ext4_split_convert_extents() fails in the
EXT4_GET_BLOCKS_PRE_IO case within ext4_ext_handle_unwritten_extents(),
error out through the exit point at function end rather than jumping
through an intermediate point. Fix the error handling in the event
ext4_split_convert_extents() returns 0, which it shouldn't do when
splitting an existing extent. The current code returns the passed in
value of allocated (which is likely non-zero) while failing to set
m_flags, m_pblk, and m_len.
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Link: https://lore.kernel.org/r/20200430185320.23001-4-enwlinux@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Remove the redundant code assigning values to ext4_map_blocks components
in ext4_ext_handle_unwritten_extents() for the EXT4_GET_BLOCKS_CONVERT
case, using the code at the function exit instead. Clean up and reorder
that code to eliminate more redundancy and improve readability.
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Link: https://lore.kernel.org/r/20200430185320.23001-3-enwlinux@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
There's no call to ext4_map_blocks() in the current ext4 code with a
flags argument that combines EXT4_GET_BLOCKS_CONVERT and
EXT4_GET_BLOCKS_ZERO. Remove the code that corresponds to this case
from ext4_ext_handle_unwritten_extents().
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/20200430185320.23001-2-enwlinux@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Don't ignore return values from ext4_ext_dirty, since the errors
indicate valid failures below Ext4. In all of the other instances of
ext4_ext_dirty calls, the error return value is handled in some
way. This patch makes those remaining couple of places to handle
ext4_ext_dirty errors as well. In case of ext4_split_extent_at(), the
ignorance of return value is intentional. The reason is that we are
already in error path and there isn't much we can do if ext4_ext_dirty
returns error. This patch adds a comment for that case explaining why
we ignore the return value.
In the longer run, we probably should
make sure that errors from other mark_dirty routines are handled as
well.
Ran gce-xfstests smoke tests and verified that there were no
regressions.
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200427013438.219117-2-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
ext4_mark_inode_dirty() can fail for real reasons. Ignoring its return
value may lead ext4 to ignore real failures that would result in
corruption / crashes. Harden ext4_mark_inode_dirty error paths to fail
as soon as possible and return errors to the caller whenever
appropriate.
One of the possible scnearios when this bug could affected is that
while creating a new inode, its directory entry gets added
successfully but while writing the inode itself mark_inode_dirty
returns error which is ignored. This would result in inconsistency
that the directory entry points to a non-existent inode.
Ran gce-xfstests smoke tests and verified that there were no
regressions.
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20200427013438.219117-1-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The eofblocks code was removed in the 5.7 release by "ext4: remove
EOFBLOCKS_FL and associated code" (4337ecd1fe). The ext4_map_blocks()
flag used to trigger it can now be removed as well.
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200415203140.30349-2-enwlinux@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
We do not want to create initialized extents beyond end of file because
for e2fsck it is impossible to distinguish them from a case of corrupted
file size / extent tree and so it complains like:
Inode 12, i_size is 147456, should be 163840. Fix? no
Code in ext4_ext_convert_to_initialized() and
ext4_split_convert_extents() try to make sure it does not create
initialized extents beyond inode size however they check against
inode->i_size which is wrong. They should instead check against
EXT4_I(inode)->i_disksize which is the current inode size on disk.
That's what e2fsck is going to see in case of crash before all dirty
data is written. This bug manifests as generic/456 test failure (with
recent enough fstests where fsx got fixed to properly pass
FALLOC_KEEP_SIZE_FL flags to the kernel) when run with dioread_lock
mount option.
CC: stable@vger.kernel.org
Fixes: 21ca087a38 ("ext4: Do not zero out uninitialized extents beyond i_size")
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/20200331105016.8674-1-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Using a separate function, ext4_set_errno() to set the errno is
problematic because it doesn't do the right thing once
s_last_error_errorcode is non-zero. It's also less racy to set all of
the error information all at once. (Also, as a bonus, it shrinks code
size slightly.)
Link: https://lore.kernel.org/r/20200329020404.686965-1-tytso@mit.edu
Fixes: 878520ac45 ("ext4: save the error code which triggered...")
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
We can use the variable allocated_clusters rather than map_from_clusters
to control reserved block/cluster accounting in ext4_ext_map_blocks.
This eliminates a variable and associated code and improves readability
a little.
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Link: https://lore.kernel.org/r/20200311205125.25061-1-enwlinux@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Now that the eofblocks code has been removed, we don't need to assign
0 to err before calling ext4_ext_insert_extent() since it will assign
a return value to ret anyway. The variable free_on_err can be
eliminated and replaced by a reference to allocated_clusters which
clearly conveys the idea that newly allocated blocks should be freed
when recovering from an extent insertion failure. The error handling
code itself should be restructured so that it errors out immediately on
an insertion failure in the case where no new blocks have been allocated
(bigalloc) rather than proceeding further into the mapping code. The
initializer for fb_flags can also be rearranged for improved
readability. Finally, insert a missing space in nearby code.
No known bugs are addressed by this patch - it's simply a cleanup.
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Link: https://lore.kernel.org/r/20200311205033.25013-1-enwlinux@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This patch moves ext4_fiemap to use iomap framework.
For xattr a new 'ext4_iomap_xattr_ops' is added.
Reported-by: kbuild test robot <lkp@intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Link: https://lore.kernel.org/r/b9f45c885814fcdd0631747ff0fe08886270828c.1582880246.git.riteshh@linux.ibm.com
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This patch avoids the memory alloc & free path when depth is 0,
since anyway there is no extra caching done in that case.
So on checking depth 0, simply return early.
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/93da0d0f073c73358e85bb9849d8a5378d1da539.1582880246.git.riteshh@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Although convert_initialized_extent() can potentially return an error
code with a negative value, its returned value is assigned to an
unsigned variable containing a block count in ext4_ext_map_blocks() and
then returned to that function's caller. The code currently works,
though the way this happens is obscure. The code would be more
readable if it followed the error handling convention used elsewhere
in ext4_ext_map_blocks().
This patch does not address any known test failure or bug report - it's
simply a cleanup. It also addresses a nearby coding standard issue.
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Link: https://lore.kernel.org/r/20200218202656.21561-1-enwlinux@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
There are no forward references for ext4_split_extent() in extents.c,
so delete its unnecessary declaration.
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Link: https://lore.kernel.org/r/20200212162141.22381-1-enwlinux@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The EXT4_EOFBLOCKS_FL inode flag is used to indicate whether a file
contains unwritten blocks past i_size. It's set when ext4_fallocate
is called with the KEEP_SIZE flag to extend a file with an unwritten
extent. However, this flag hasn't been useful functionally since
March, 2012, when a decision was made to remove it from ext4.
All traces of EXT4_EOFBLOCKS_FL were removed from e2fsprogs version
1.42.2 by commit 010dc7b90d97 ("e2fsck: remove EXT4_EOFBLOCKS_FL flag
handling") at that time. Now that enough time has passed to make
e2fsprogs versions containing this modification common, this patch now
removes the code associated with EXT4_EOFBLOCKS_FL from the kernel as
well.
This change has two implications. First, because pre-1.42.2 e2fsck
versions only look for a problem if EXT4_EOFBLOCKS_FL is set, and
because that bit will never be set by newer kernels containing this
patch, old versions of e2fsck won't have a compatibility problem with
files created by newer kernels.
Second, newer kernels will not clear EXT4_EOFBLOCKS_FL inode flag bits
belonging to a file written by an older kernel. If set, it will remain
in that state until the file is deleted. Because e2fsck versions since
1.42.2 don't check the flag at all, no adverse effect is expected.
However, pre-1.42.2 e2fsck versions that do check the flag may report
that it is set when it ought not to be after a file has been truncated
or had its unwritten blocks written. In this case, the old version of
e2fsck will offer to clear the flag. No adverse effect would then
occur whether the user chooses to clear the flag or not.
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Link: https://lore.kernel.org/r/20200211210216.24960-1-enwlinux@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Extents are cached in read_extent_tree_block(); as a result, extents
are not cached for inodes with depth == 0 when we try to find the
extent using ext4_find_extent(). The result of the lookup is cached
in ext4_map_blocks() but is only a subset of the extent on disk. As a
result, the contents of extents status cache can get very badly
fragmented for certain workloads, such as a random 4k read workload.
File size of /mnt/test is 33554432 (8192 blocks of 4096 bytes)
ext: logical_offset: physical_offset: length: expected: flags:
0: 0.. 8191: 40960.. 49151: 8192: last,eof
$ perf record -e 'ext4:ext4_es_*' /root/bin/fio --name=t --direct=0 --rw=randread --bs=4k --filesize=32M --size=32M --filename=/mnt/test
$ perf script | grep ext4_es_insert_extent | head -n 10
fio 131 [000] 13.975421: ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [494/1) mapped 41454 status W
fio 131 [000] 13.975939: ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [6064/1) mapped 47024 status W
fio 131 [000] 13.976467: ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [6907/1) mapped 47867 status W
fio 131 [000] 13.976937: ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [3850/1) mapped 44810 status W
fio 131 [000] 13.977440: ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [3292/1) mapped 44252 status W
fio 131 [000] 13.977931: ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [6882/1) mapped 47842 status W
fio 131 [000] 13.978376: ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [3117/1) mapped 44077 status W
fio 131 [000] 13.978957: ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [2896/1) mapped 43856 status W
fio 131 [000] 13.979474: ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [7479/1) mapped 48439 status W
Fix this by caching the extents for inodes with depth == 0 in
ext4_find_extent().
[ Renamed ext4_es_cache_extents() to ext4_cache_extents() since this
newly added function is not in extents_cache.c, and to avoid
potential visual confusion with ext4_es_cache_extent(). -TYT ]
Signed-off-by: Dmitry Monakhov <dmonakhov@gmail.com>
Link: https://lore.kernel.org/r/20191106122502.19986-1-dmonakhov@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
For clarity, add braces to the loop in ext4_ext_drop_refs().
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191231180444.46586-9-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Clean up some code that was using 2-character indents.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191231180444.46586-8-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Support for unwritten extents was added to ext4 a long time ago, so
remove a misleading comment that says they're a future feature.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191231180444.46586-7-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Don't mention the nonexistent return value, and mention both types of
merges that are attempted.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191231180444.46586-6-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Make the following functions static since they're only used in
extents.c:
__ext4_ext_dirty()
ext4_can_extents_be_merged()
ext4_collapse_range()
ext4_insert_range()
Also remove the prototype for ext4_ext_writepage_trans_blocks(), as this
function is not defined anywhere.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191231180444.46586-5-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
ext4_fallocate() is only used in the file_operations for regular files.
Also, the VFS only allows fallocate() on regular files and block
devices, but block devices always use blkdev_fallocate(). For both of
these reasons, S_ISREG() is always true in ext4_fallocate().
Therefore the S_ISREG() checks in ext4_zero_range(),
ext4_collapse_range(), ext4_insert_range(), and ext4_punch_hole() are
redundant. Remove them.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191231180444.46586-4-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
- Fix some comments.
- Consistently access i_size directly rather than using i_size_read(),
since in all relevant cases we're under inode_lock().
- Simplify the alignment checks by using the IS_ALIGNED() macro.
- In ext4_insert_range(), do the check against s_maxbytes in a way
that is safe against signed overflow. (This doesn't currently matter
for ext4 due to ext4's limited max file size, but this is something
other filesystems have gotten wrong. We might as well do it safely.)
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191231180444.46586-3-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Remove the ext4_ind_calc_metadata_amount() and
ext4_ext_calc_metadata_amount() functions, which have been unused since
commit 71d4f7d032 ("ext4: remove metadata reservation checks").
Also remove the i_da_metadata_calc_last_lblock and
i_da_metadata_calc_len fields from struct ext4_inode_info, as these were
only used by these removed functions.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191231180444.46586-2-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
For encrypted files, commit 36086d43f6 ("ext4 crypto: fix bugs in
ext4_encrypted_zeroout()") disabled the optimization where when a write
occurs to the middle of an unwritten extent, the head and/or tail of the
extent (when they aren't too large) are zeroed out, turned into an
initialized extent, and merged with the part being written to. This
optimization helps prevent fragmentation of the extent tree.
However, disabling this optimization also made fscrypt_zeroout_range()
nearly impossible to test, as now it's only reachable via the very rare
case in ext4_split_extent_at() where allocating a new extent tree block
fails due to ENOSPC. 'gce-xfstests -c ext4/encrypt -g auto' doesn't
even hit this at all.
It's preferable to avoid really rare cases that are hard to test.
That commit also cited data corruption in xfstest generic/127 as a
reason to disable the extent zeroout optimization, but that's no longer
reproducible anymore. It also cited fscrypt_zeroout_range() having poor
performance, but I've written a patch to fix that.
Therefore, re-enable the extent zeroout optimization on encrypted files.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191226161114.53606-1-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
When ext4 encryption support was first added, ZERO_RANGE was disallowed,
supposedly because test failures (e.g. ext4/001) were seen when enabling
it, and at the time there wasn't enough time/interest to debug it.
However, there's actually no reason why ZERO_RANGE can't work on
encrypted files. And it fact it *does* work now. Whole blocks in the
zeroed range are converted to unwritten extents, as usual; encryption
makes no difference for that part. Partial blocks are zeroed in the
pagecache and then ->writepages() encrypts those blocks as usual.
ext4_block_zero_page_range() handles reading and decrypting the block if
needed before actually doing the pagecache write.
Also, f2fs has always supported ZERO_RANGE on encrypted files.
As far as I can tell, the reason that ext4/001 was failing in v4.1 was
actually because of one of the bugs fixed by commit 36086d43f6 ("ext4
crypto: fix bugs in ext4_encrypted_zeroout()"). The bug made
ext4_encrypted_zeroout() always return a positive value, which caused
unwritten extents in encrypted files to sometimes not be marked as
initialized after being written to. This bug was not actually in
ZERO_RANGE; it just happened to trigger during the extents manipulation
done in ext4/001 (and probably other tests too).
So, let's enable ZERO_RANGE on encrypted files on ext4.
Tested with:
gce-xfstests -c ext4/encrypt -g auto
gce-xfstests -c ext4/encrypt_1k -g auto
Got the same set of test failures both with and without this patch.
But with this patch 6 fewer tests are skipped: ext4/001, generic/008,
generic/009, generic/033, generic/096, and generic/511.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191226154216.4808-1-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This allows the cause of an ext4_error() report to be categorized
based on whether it was triggered due to an I/O error, or an memory
allocation error, or other possible causes. Most errors are caused by
a detected file system inconsistency, so the default code stored in
the superblock will be EXT4_ERR_EFSCORRUPTED.
Link: https://lore.kernel.org/r/20191204032335.7683-1-tytso@mit.edu
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
So far we have reserved only relatively high fixed amount of revoke
credits for each transaction. We over-reserved by large amount for most
cases but when freeing large directories or files with data journalling,
the fixed amount is not enough. In fact the worst case estimate is
inconveniently large (maximum extent size) for freeing of one extent.
We fix this by doing proper estimate of the amount of blocks that need
to be revoked when removing blocks from the inode due to truncate or
hole punching and otherwise reserve just a small amount of revoke
credits for each transaction to accommodate freeing of xattrs block or
so.
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-23-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Provide ext4_journal_ensure_credits_fn() function to ensure transaction
has given amount of credits and call helper function to prepare for
restarting a transaction. This allows to remove some boilerplate code
from various places, add proper error handling for the case where
transaction extension or restart fails, and reduces following changes
needed for proper revoke record reservation tracking.
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-10-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This patch introduces a new direct I/O write path which makes use of
the iomap infrastructure.
All direct I/O writes are now passed from the ->write_iter() callback
through to the new direct I/O handler ext4_dio_write_iter(). This
function is responsible for calling into the iomap infrastructure via
iomap_dio_rw().
Code snippets from the existing direct I/O write code within
ext4_file_write_iter() such as, checking whether the I/O request is
unaligned asynchronous I/O, or whether the write will result in an
overwrite have effectively been moved out and into the new direct I/O
->write_iter() handler.
The block mapping flags that are eventually passed down to
ext4_map_blocks() from the *_get_block_*() suite of routines have been
taken out and introduced within ext4_iomap_alloc().
For inode extension cases, ext4_handle_inode_extension() is
effectively the function responsible for performing such metadata
updates. This is called after iomap_dio_rw() has returned so that we
can safely determine whether we need to potentially truncate any
allocated blocks that may have been prepared for this direct I/O
write. We don't perform the inode extension, or truncate operations
from the ->end_io() handler as we don't have the original I/O 'length'
available there. The ->end_io() however is responsible fo converting
allocated unwritten extents to written extents.
In the instance of a short write, we fallback and complete the
remainder of the I/O using buffered I/O via
ext4_buffered_write_iter().
The existing buffer_head direct I/O implementation has been removed as
it's now redundant.
[ Fix up ext4_dio_write_iter() per Jan's comments at
https://lore.kernel.org/r/20191105135932.GN22379@quack2.suse.cz -- TYT ]
Signed-off-by: Matthew Bobrowski <mbobrowski@mbobrowski.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/e55db6f12ae6ff017f36774135e79f3e7b0333da.1572949325.git.mbobrowski@mbobrowski.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This patch adds the support for blocksize < pagesize for
dioread_nolock feature.
Since in case of blocksize < pagesize, we can have multiple
small buffers of page as unwritten extents, we need to
maintain a vector of these unwritten extents which needs
the conversion after the IO is complete. Thus, we maintain
a list of tuple <offset, size> pair (io_end_vec) for this &
traverse this list to do the unwritten to written conversion.
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/20191016073711.4141-5-riteshh@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This patch just brings in the API for conversion of unwritten io_end_vec
extents which will be required for blocksize < pagesize support
for dioread_nolock feature.
No functional changes in this patch.
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/20191016073711.4141-3-riteshh@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
