summaryrefslogtreecommitdiffstats
path: root/fs/ext4/extents.c
Commit message (Collapse)AuthorAgeFilesLines
* ext4: fix bigalloc cluster freeing when hole punching under loadEric Whitney2019-04-051-7/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 7bd75230b43727b258a4f7a59d62114cffe1b6c8 ] Ext4 may not free clusters correctly when punching holes in bigalloc file systems under high load conditions. If it's not possible to extend and restart the journal in ext4_ext_rm_leaf() when preparing to remove blocks from a punched region, a retry of the entire punch operation is triggered in ext4_ext_remove_space(). This causes a partial cluster to be set to the first cluster in the extent found to the right of the punched region. However, if the punch operation prior to the retry had made enough progress to delete one or more extents and a partial cluster candidate for freeing had already been recorded, the retry would overwrite the partial cluster. The loss of this information makes it impossible to correctly free the original partial cluster in all cases. This bug can cause generic/476 to fail when run as part of xfstests-bld's bigalloc and bigalloc_1k test cases. The failure is reported when e2fsck detects bad iblocks counts greater than expected in units of whole clusters and also detects a number of negative block bitmap differences equal to the iblocks discrepancy in cluster units. Signed-off-by: Eric Whitney <enwlinux@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Sasha Levin <sashal@kernel.org>
* ext4: adjust reserved cluster count when removing extentsEric Whitney2018-10-011-111/+173
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Modify ext4_ext_remove_space() and the code it calls to correct the reserved cluster count for pending reservations (delayed allocated clusters shared with allocated blocks) when a block range is removed from the extent tree. Pending reservations may be found for the clusters at the ends of written or unwritten extents when a block range is removed. If a physical cluster at the end of an extent is freed, it's necessary to increment the reserved cluster count to maintain correct accounting if the corresponding logical cluster is shared with at least one delayed and unwritten extent as found in the extents status tree. Add a new function, ext4_rereserve_cluster(), to reapply a reservation on a delayed allocated cluster sharing blocks with a freed allocated cluster. To avoid ENOSPC on reservation, a flag is applied to ext4_free_blocks() to briefly defer updating the freeclusters counter when an allocated cluster is freed. This prevents another thread from allocating the freed block before the reservation can be reapplied. Redefine the partial cluster object as a struct to carry more state information and to clarify the code using it. Adjust the conditional code structure in ext4_ext_remove_space to reduce the indentation level in the main body of the code to improve readability. Signed-off-by: Eric Whitney <enwlinux@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: reduce reserved cluster count by number of allocated clustersEric Whitney2018-10-011-160/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | Ext4 does not always reduce the reserved cluster count by the number of clusters allocated when mapping a delayed extent. It sometimes adds back one or more clusters after allocation if delalloc blocks adjacent to the range allocated by ext4_ext_map_blocks() share the clusters newly allocated for that range. However, this overcounts the number of clusters needed to satisfy future mapping requests (holding one or more reservations for clusters that have already been allocated) and premature ENOSPC and quota failures, etc., result. Ext4 also does not reduce the reserved cluster count when allocating clusters for non-delayed allocated writes that have previously been reserved for delayed writes. This also results in overcounts. To make it possible to handle reserved cluster accounting for fallocated regions in the same manner as used for other non-delayed writes, do the reserved cluster accounting for them at the time of allocation. In the current code, this is only done later when a delayed extent sharing the fallocated region is finally mapped. Address comment correcting handling of unsigned long long constant from Jan Kara's review of RFC version of this patch. Signed-off-by: Eric Whitney <enwlinux@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: fix reserved cluster accounting at delayed write timeEric Whitney2018-10-011-0/+79
| | | | | | | | | | | | | | The code in ext4_da_map_blocks sometimes reserves space for more delayed allocated clusters than it should, resulting in premature ENOSPC, exceeded quota, and inaccurate free space reporting. Fix this by checking for written and unwritten blocks shared in the same cluster with the newly delayed allocated block. A cluster reservation should not be made for a cluster for which physical space has already been allocated. Signed-off-by: Eric Whitney <enwlinux@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: generalize extents status tree search functionsEric Whitney2018-10-011-40/+12
| | | | | | | | | | | | | | | | | | Ext4 contains a few functions that are used to search for delayed extents or blocks in the extents status tree. Rather than duplicate code to add new functions to search for extents with different status values, such as written or a combination of delayed and unwritten, generalize the existing code to search for caller-specified extents status values. Also, move this code into extents_status.c where it is better associated with the data structures it operates upon, and where it can be more readily used to implement new extents status tree functions that might want a broader scope for i_es_lock. Three missing static specifiers in RFC version of patch reported and fixed by Fengguang Wu <fengguang.wu@intel.com>. Signed-off-by: Eric Whitney <enwlinux@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: handle layout changes to pinned DAX mappingsRoss Zwisler2018-07-291-0/+17
| | | | | | | | | | | Follow the lead of xfs_break_dax_layouts() and add synchronization between operations in ext4 which remove blocks from an inode (hole punch, truncate down, etc.) and pages which are pinned due to DAX DMA operations. Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Lukas Czerner <lczerner@redhat.com>
* Merge tag 'ext4_for_linus_stable' of ↵Linus Torvalds2018-07-081-0/+6
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 bugfixes from Ted Ts'o: "Bug fixes for ext4; most of which relate to vulnerabilities where a maliciously crafted file system image can result in a kernel OOPS or hang. At least one fix addresses an inline data bug could be triggered by userspace without the need of a crafted file system (although it does require that the inline data feature be enabled)" * tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: ext4: check superblock mapped prior to committing ext4: add more mount time checks of the superblock ext4: add more inode number paranoia checks ext4: avoid running out of journal credits when appending to an inline file jbd2: don't mark block as modified if the handle is out of credits ext4: never move the system.data xattr out of the inode body ext4: clear i_data in ext4_inode_info when removing inline data ext4: include the illegal physical block in the bad map ext4_error msg ext4: verify the depth of extent tree in ext4_find_extent() ext4: only look at the bg_flags field if it is valid ext4: make sure bitmaps and the inode table don't overlap with bg descriptors ext4: always check block group bounds in ext4_init_block_bitmap() ext4: always verify the magic number in xattr blocks ext4: add corruption check in ext4_xattr_set_entry() ext4: add warn_on_error mount option
| * ext4: verify the depth of extent tree in ext4_find_extent()Theodore Ts'o2018-06-141-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | If there is a corupted file system where the claimed depth of the extent tree is -1, this can cause a massive buffer overrun leading to sadness. This addresses CVE-2018-10877. https://bugzilla.kernel.org/show_bug.cgi?id=199417 Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
* | treewide: kzalloc() -> kcalloc()Kees Cook2018-06-121-4/+4
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The kzalloc() function has a 2-factor argument form, kcalloc(). This patch replaces cases of: kzalloc(a * b, gfp) with: kcalloc(a * b, gfp) as well as handling cases of: kzalloc(a * b * c, gfp) with: kzalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kzalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kzalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kzalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kzalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kzalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(char) * COUNT + COUNT , ...) | kzalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kzalloc + kcalloc ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kzalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kzalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kzalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kzalloc(C1 * C2 * C3, ...) | kzalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kzalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kzalloc(sizeof(THING) * C2, ...) | kzalloc(sizeof(TYPE) * C2, ...) | kzalloc(C1 * C2 * C3, ...) | kzalloc(C1 * C2, ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - (E1) * E2 + E1, E2 , ...) | - kzalloc + kcalloc ( - (E1) * (E2) + E1, E2 , ...) | - kzalloc + kcalloc ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
* ext4: prevent right-shifting extents beyond EXT_MAX_BLOCKSEric Biggers2018-04-121-5/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | During the "insert range" fallocate operation, extents starting at the range offset are shifted "right" (to a higher file offset) by the range length. But, as shown by syzbot, it's not validated that this doesn't cause extents to be shifted beyond EXT_MAX_BLOCKS. In that case ->ee_block can wrap around, corrupting the extent tree. Fix it by returning an error if the space between the end of the last extent and EXT4_MAX_BLOCKS is smaller than the range being inserted. This bug can be reproduced by running the following commands when the current directory is on an ext4 filesystem with a 4k block size: fallocate -l 8192 file fallocate --keep-size -o 0xfffffffe000 -l 4096 -n file fallocate --insert-range -l 8192 file Then after unmounting the filesystem, e2fsck reports corruption. Reported-by: syzbot+06c885be0edcdaeab40c@syzkaller.appspotmail.com Fixes: 331573febb6a ("ext4: Add support FALLOC_FL_INSERT_RANGE for fallocate") Cc: stable@vger.kernel.org # v4.2+ Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: fix comments in ext4_swap_extents()zhenwei.pi2018-03-261-2/+2
| | | | | | | | "mark_unwritten" in comment and "unwritten" in the function arguments is mismatched. Signed-off-by: zhenwei.pi <zhenwei.pi@youruncloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: remove EXT4_STATE_DIOREAD_LOCK flagNikolay Borisov2018-03-221-14/+5
| | | | | | | | | | | | Commit 16c54688592c ("ext4: Allow parallel DIO reads") reworked the way locking happens around parallel dio reads. This resulted in obviating the need for EXT4_STATE_DIOREAD_LOCK flag and accompanying logic. Currently this amounts to dead code so let's remove it. No functional changes Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz>
* ext4: fix up remaining files with SPDX cleanupsTheodore Ts'o2017-12-171-13/+1
| | | | | | | | | | | | | | | | | | | | A number of ext4 source files were skipped due because their copyright permission statements didn't match the expected text used by the automated conversion utilities. I've added SPDX tags for the rest. While looking at some of these files, I've noticed that we have quite a bit of variation on the licenses that were used --- in particular some of the Red Hat licenses on the jbd2 files use a GPL2+ license, and we have some files that have a LGPL-2.1 license (which was quite surprising). I've not attempted to do any license changes. Even if it is perfectly legal to relicense to GPL 2.0-only for consistency's sake, that should be done with ext4 developer community discussion. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: fix fdatasync(2) after fallocate(2) operationEryu Guan2017-12-031-0/+1
| | | | | | | | | | | | | | | | | | | | | | Currently, fallocate(2) with KEEP_SIZE followed by a fdatasync(2) then crash, we'll see wrong allocated block number (stat -c %b), the blocks allocated beyond EOF are all lost. fstests generic/468 exposes this bug. Commit 67a7d5f561f4 ("ext4: fix fdatasync(2) after extent manipulation operations") fixed all the other extent manipulation operation paths such as hole punch, zero range, collapse range etc., but forgot the fallocate case. So similarly, fix it by recording the correct journal tid in ext4 inode in fallocate(2) path, so that ext4_sync_file() will wait for the right tid to be committed on fdatasync(2). This addresses the test failure in xfstests test generic/468. Signed-off-by: Eryu Guan <eguan@redhat.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@vger.kernel.org
* ext4: fix interaction between i_size, fallocate, and delalloc after a crashTheodore Ts'o2017-10-061-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If there are pending writes subject to delayed allocation, then i_size will show size after the writes have completed, while i_disksize contains the value of i_size on the disk (since the writes have not been persisted to disk). If fallocate(2) is called with the FALLOC_FL_KEEP_SIZE flag, either with or without the FALLOC_FL_ZERO_RANGE flag set, and the new size after the fallocate(2) is between i_size and i_disksize, then after a crash, if a journal commit has resulted in the changes made by the fallocate() call to be persisted after a crash, but the delayed allocation write has not resolved itself, i_size would not be updated, and this would cause the following e2fsck complaint: Inode 12, end of extent exceeds allowed value (logical block 33, physical block 33441, len 7) This can only take place on a sparse file, where the fallocate(2) call is allocating blocks in a range which is before a pending delayed allocation write which is extending i_size. Since this situation is quite rare, and the window in which the crash must take place is typically < 30 seconds, in practice this condition will rarely happen. Nevertheless, it can be triggered in testing, and in particular by xfstests generic/456. Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reported-by: Amir Goldstein <amir73il@gmail.com> Cc: stable@vger.kernel.org
* ext4: fix copy paste error in ext4_swap_extents()Maninder Singh2017-08-061-1/+1
| | | | | | | | | This bug was found by a static code checker tool for copy paste problems. Signed-off-by: Maninder Singh <maninder1.s@samsung.com> Signed-off-by: Vaneet Narang <v.narang@samsung.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: remove unused mode parameterTahsin Erdogan2017-08-051-5/+4
| | | | | | | ext4_alloc_file_blocks() does not use its mode parameter. Remove it. Signed-off-by: Tahsin Erdogan <tahsin@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: call journal revoke when freeing ea_inode blocksTahsin Erdogan2017-06-211-1/+2
| | | | | | | | | | ea_inode contents are treated as metadata, that's why it is journaled during initial writes. Failing to call revoke during freeing could cause user data to be overwritten with original ea_inode contents during journal replay. Signed-off-by: Tahsin Erdogan <tahsin@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: fix fdatasync(2) after extent manipulation operationsJan Kara2017-05-291-0/+5
| | | | | | | | | | | | | | | | | Currently, extent manipulation operations such as hole punch, range zeroing, or extent shifting do not record the fact that file data has changed and thus fdatasync(2) has a work to do. As a result if we crash e.g. after a punch hole and fdatasync, user can still possibly see the punched out data after journal replay. Test generic/392 fails due to these problems. Fix the problem by properly marking that file data has changed in these operations. CC: stable@vger.kernel.org Fixes: a4bb6b64e39abc0e41ca077725f2a72c868e7622 Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: fix data corruption with EXT4_GET_BLOCKS_ZEROJan Kara2017-05-261-43/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When ext4_map_blocks() is called with EXT4_GET_BLOCKS_ZERO to zero-out allocated blocks and these blocks are actually converted from unwritten extent the following race can happen: CPU0 CPU1 page fault page fault ... ... ext4_map_blocks() ext4_ext_map_blocks() ext4_ext_handle_unwritten_extents() ext4_ext_convert_to_initialized() - zero out converted extent ext4_zeroout_es() - inserts extent as initialized in status tree ext4_map_blocks() ext4_es_lookup_extent() - finds initialized extent write data ext4_issue_zeroout() - zeroes out new extent overwriting data This problem can be reproduced by generic/340 for the fallocated case for the last block in the file. Fix the problem by avoiding zeroing out the area we are mapping with ext4_map_blocks() in ext4_ext_convert_to_initialized(). It is pointless to zero out this area in the first place as the caller asked us to convert the area to initialized because he is just going to write data there before the transaction finishes. To achieve this we delete the special case of zeroing out full extent as that will be handled by the cases below zeroing only the part of the extent that needs it. We also instruct ext4_split_extent() that the middle of extent being split contains data so that ext4_split_extent_at() cannot zero out full extent in case of ENOSPC. CC: stable@vger.kernel.org Fixes: 12735f881952c32b31bc4e433768f18489f79ec9 Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: do not polute the extents cache while shifting extentsRoman Pen2017-01-081-3/+6
| | | | | | | | | | | | | | | | | | Inside ext4_ext_shift_extents() function ext4_find_extent() is called without EXT4_EX_NOCACHE flag, which should prevent cache population. This leads to oudated offsets in the extents tree and wrong blocks afterwards. Patch fixes the problem providing EXT4_EX_NOCACHE flag for each ext4_find_extents() call inside ext4_ext_shift_extents function. Fixes: 331573febb6a2 Signed-off-by: Roman Pen <roman.penyaev@profitbricks.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: Namjae Jeon <namjae.jeon@samsung.com> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: stable@vger.kernel.org
* ext4: Include forgotten start block on fallocate insert rangeRoman Pen2017-01-081-6/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While doing 'insert range' start block should be also shifted right. The bug can be easily reproduced by the following test: ptr = malloc(4096); assert(ptr); fd = open("./ext4.file", O_CREAT | O_TRUNC | O_RDWR, 0600); assert(fd >= 0); rc = fallocate(fd, 0, 0, 8192); assert(rc == 0); for (i = 0; i < 2048; i++) *((unsigned short *)ptr + i) = 0xbeef; rc = pwrite(fd, ptr, 4096, 0); assert(rc == 4096); rc = pwrite(fd, ptr, 4096, 4096); assert(rc == 4096); for (block = 2; block < 1000; block++) { rc = fallocate(fd, FALLOC_FL_INSERT_RANGE, 4096, 4096); assert(rc == 0); for (i = 0; i < 2048; i++) *((unsigned short *)ptr + i) = block; rc = pwrite(fd, ptr, 4096, 4096); assert(rc == 4096); } Because start block is not included in the range the hole appears at the wrong offset (just after the desired offset) and the following pwrite() overwrites already existent block, keeping hole untouched. Simple way to verify wrong behaviour is to check zeroed blocks after the test: $ hexdump ./ext4.file | grep '0000 0000' The root cause of the bug is a wrong range (start, stop], where start should be inclusive, i.e. [start, stop]. This patch fixes the problem by including start into the range. But not to break left shift (range collapse) stop points to the beginning of the a block, not to the end. The other not obvious change is an iterator check on validness in a main loop. Because iterator is unsigned the following corner case should be considered with care: insert a block at 0 offset, when stop variables overflows and never becomes less than start, which is 0. To handle this special case iterator is set to NULL to indicate that end of the loop is reached. Fixes: 331573febb6a2 Signed-off-by: Roman Pen <roman.penyaev@profitbricks.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: Namjae Jeon <namjae.jeon@samsung.com> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: stable@vger.kernel.org
* Replace <asm/uaccess.h> with <linux/uaccess.h> globallyLinus Torvalds2016-12-241-1/+1
| | | | | | | | | | | | | This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>' sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'for-4.10/fs-unmap' of git://git.kernel.dk/linux-blockLinus Torvalds2016-12-141-11/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull fs meta data unmap optimization from Jens Axboe: "A series from Jan Kara, providing a more efficient way for unmapping meta data from in the buffer cache than doing it block-by-block. Provide a general helper that existing callers can use" * 'for-4.10/fs-unmap' of git://git.kernel.dk/linux-block: fs: Remove unmap_underlying_metadata fs: Add helper to clean bdev aliases under a bh and use it ext2: Use clean_bdev_aliases() instead of iteration ext4: Use clean_bdev_aliases() instead of iteration direct-io: Use clean_bdev_aliases() instead of handmade iteration fs: Provide function to unmap metadata for a range of blocks
| * ext4: Use clean_bdev_aliases() instead of iterationJan Kara2016-11-041-11/+2
| | | | | | | | | | | | | | Use clean_bdev_aliases() instead of iterating through blocks one by one. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@fb.com>
* | ext4: remove another test in ext4_alloc_file_blocks()Dan Carpenter2016-12-031-1/+1
| | | | | | | | | | | | | | | | | | | | Before commit c3fe493ccdb1 ('ext4: remove unneeded test in ext4_alloc_file_blocks()') then it was possible for "depth" to be -1 but now, it's not possible that it is negative. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz>
* | ext4: use current_time() for inode timestampsDeepa Dinamani2016-11-141-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | CURRENT_TIME_SEC and CURRENT_TIME are not y2038 safe. current_time() will be transitioned to be y2038 safe along with vfs. current_time() returns timestamps according to the granularities set in the super_block. The granularity check in ext4_current_time() to call current_time() or CURRENT_TIME_SEC is not required. Use current_time() directly to obtain timestamps unconditionally, and remove ext4_current_time(). Quota files are assumed to be on the same filesystem. Hence, use current_time() for these files as well. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Arnd Bergmann <arnd@arndb.de>
* | ext4: allow ext4_ext_truncate() to return an errorTheodore Ts'o2016-11-131-8/+7
|/ | | | | | | | Return errors to the caller instead of declaring the file system corrupted. Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz>
* ext4: create EXT4_MAX_BLOCKS() macroFabian Frederick2016-09-151-12/+3
| | | | | | | | Create a macro to calculate length + offset -> maximum blocks This adds more readability. Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: remove unneeded test in ext4_alloc_file_blocks()Fabian Frederick2016-09-151-7/+2
| | | | | | | | | | | | ext4_alloc_file_blocks() is called from ext4_zero_range() and ext4_fallocate() both already testing EXT4_INODE_EXTENTS We can call ext_depth(inode) unconditionnally. [ Added BUG_ON check to make sure ext4_alloc_file_blocks() won't get called for a indirect-mapped inode in the future. -- tytso ] Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: fix memory leak in ext4_insert_range()Fabian Frederick2016-09-151-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | Running xfstests generic/013 with kmemleak gives the following: unreferenced object 0xffff8801d3d27de0 (size 96): comm "fsstress", pid 4941, jiffies 4294860168 (age 53.485s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 01 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff818eaaf3>] kmemleak_alloc+0x23/0x40 [<ffffffff81179805>] __kmalloc+0xf5/0x1d0 [<ffffffff8122ef5c>] ext4_find_extent+0x1ec/0x2f0 [<ffffffff8123530c>] ext4_insert_range+0x34c/0x4a0 [<ffffffff81235942>] ext4_fallocate+0x4e2/0x8b0 [<ffffffff81181334>] vfs_fallocate+0x134/0x210 [<ffffffff8118203f>] SyS_fallocate+0x3f/0x60 [<ffffffff818efa9b>] entry_SYSCALL_64_fastpath+0x13/0x8f [<ffffffffffffffff>] 0xffffffffffffffff Problem seems mitigated by dropping refs and freeing path when there's no path[depth].p_ext Cc: stable@vger.kernel.org Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: verify extent header depthVegard Nossum2016-07-151-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Although the extent tree depth of 5 should enough be for the worst case of 2*32 extents of length 1, the extent tree code does not currently to merge nodes which are less than half-full with a sibling node, or to shrink the tree depth if possible. So it's possible, at least in theory, for the tree depth to be greater than 5. However, even in the worst case, a tree depth of 32 is highly unlikely, and if the file system is maliciously corrupted, an insanely large eh_depth can cause memory allocation failures that will trigger kernel warnings (here, eh_depth = 65280): JBD2: ext4.exe wants too many credits credits:195849 rsv_credits:0 max:256 ------------[ cut here ]------------ WARNING: CPU: 0 PID: 50 at fs/jbd2/transaction.c:293 start_this_handle+0x569/0x580 CPU: 0 PID: 50 Comm: ext4.exe Not tainted 4.7.0-rc5+ #508 Stack: 604a8947 625badd8 0002fd09 00000000 60078643 00000000 62623910 601bf9bc 62623970 6002fc84 626239b0 900000125 Call Trace: [<6001c2dc>] show_stack+0xdc/0x1a0 [<601bf9bc>] dump_stack+0x2a/0x2e [<6002fc84>] __warn+0x114/0x140 [<6002fdff>] warn_slowpath_null+0x1f/0x30 [<60165829>] start_this_handle+0x569/0x580 [<60165d4e>] jbd2__journal_start+0x11e/0x220 [<60146690>] __ext4_journal_start_sb+0x60/0xa0 [<60120a81>] ext4_truncate+0x131/0x3a0 [<60123677>] ext4_setattr+0x757/0x840 [<600d5d0f>] notify_change+0x16f/0x2a0 [<600b2b16>] do_truncate+0x76/0xc0 [<600c3e56>] path_openat+0x806/0x1300 [<600c55c9>] do_filp_open+0x89/0xf0 [<600b4074>] do_sys_open+0x134/0x1e0 [<600b4140>] SyS_open+0x20/0x30 [<6001ea68>] handle_syscall+0x88/0x90 [<600295fd>] userspace+0x3fd/0x500 [<6001ac55>] fork_handler+0x85/0x90 ---[ end trace 08b0b88b6387a244 ]--- [ Commit message modified and the extent tree depath check changed from 5 to 32 -- tytso ] Cc: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: check for extents that wrap aroundVegard Nossum2016-06-301-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | An extent with lblock = 4294967295 and len = 1 will pass the ext4_valid_extent() test: ext4_lblk_t last = lblock + len - 1; if (len == 0 || lblock > last) return 0; since last = 4294967295 + 1 - 1 = 4294967295. This would later trigger the BUG_ON(es->es_lblk + es->es_len < es->es_lblk) in ext4_es_end(). We can simplify it by removing the - 1 altogether and changing the test to use lblock + len <= lblock, since now if len = 0, then lblock + 0 == lblock and it fails, and if len > 0 then lblock + len > lblock in order to pass (i.e. it doesn't overflow). Fixes: 5946d0893 ("ext4: check for overlapping extents in ext4_valid_extent_entries()") Fixes: 2f974865f ("ext4: check for zero length extent explicitly") Cc: Eryu Guan <guaneryu@gmail.com> Cc: stable@vger.kernel.org Signed-off-by: Phil Turnbull <phil.turnbull@oracle.com> Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: remove unmeetable inconsisteny check from ext4_find_extent()Nicolai Stange2016-05-051-7/+0
| | | | | | | | | | | | | | | | | | | | | | | | ext4_find_extent(), stripped down to the parts relevant to this patch, reads as ppos = 0; i = depth; while (i) { --i; ++ppos; if (unlikely(ppos > depth)) { ... ret = -EFSCORRUPTED; goto err; } } Due to the loop's bounds, the condition ppos > depth can never be met. Remove this dead code. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: remove trailing \n from ext4_warning/ext4_error callsJakub Wilk2016-04-271-2/+2
| | | | | | | Messages passed to ext4_warning() or ext4_error() don't need trailing newlines, because these function add the newlines themselves. Signed-off-by: Jakub Wilk <jwilk@jwilk.net>
* ext4: fix jbd2 handle extension in ext4_ext_truncate_extend_restart()Theodore Ts'o2016-04-251-2/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | The function jbd2_journal_extend() takes as its argument the number of new credits to be added to the handle. We weren't taking into account the currently unused handle credits; worse, we would try to extend the handle by N credits when it had N credits available. In the case where jbd2_journal_extend() fails because the transaction is too large, when jbd2_journal_restart() gets called, the N credits owned by the handle gets returned to the transaction, and the transaction commit is asynchronously requested, and then start_this_handle() will be able to successfully attach the handle to the current transaction since the required credits are now available. This is mostly harmless, but since ext4_ext_truncate_extend_restart() returns EAGAIN, the truncate machinery will once again try to call ext4_ext_truncate_extend_restart(), which will do the above sequence over and over again until the transaction has committed. This was found while I was debugging a lockup in caused by running xfstests generic/074 in the data=journal case. I'm still not sure why we ended up looping forever, which suggests there may still be another bug hiding in the transaction accounting machinery, but this commit prevents us from looping in the first place. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: fix misspellings in comments.Adam Buchbinder2016-03-091-1/+1
| | | | | Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: return hole from ext4_map_blocks()Jan Kara2016-03-091-2/+9
| | | | | | | | | | | | | Currently, ext4_map_blocks() just returns 0 when it finds a hole and allocation is not requested. However we have all the information available to tell how large the hole actually is and there are callers of ext4_map_blocks() which would save some block-by-block hole iteration if they knew this information. So fill in struct ext4_map_blocks even for holes with the information we have. We keep returning 0 for holes to maintain backward compatibility of the function. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: factor out determining of hole sizeJan Kara2016-03-091-33/+47
| | | | | | | | | | | ext4_ext_put_gap_in_cache() determines hole size in the extent tree, then trims this with possible delayed allocated blocks, and inserts the result into the extent status tree. Factor out determination of the size of the hole in the extent tree as we will need this information in ext4_ext_map_blocks() as well. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: simplify io_end handling for AIO DIOJan Kara2016-03-081-29/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | When mapping blocks for direct IO, we allocate io_end structure before mapping blocks and store pointer to it in the inode. This creates a requirement that any AIO DIO using io_end must be protected by i_mutex. This created problems in the past with dioread_nolock mode which was corrupting io_end pointers. Also io_end is allocated unnecessarily in case where we don't need to convert any extents (which is a common case for example when overwriting file). We fix the problem by allocating io_end only once we return unwritten extent from block mapping function for AIO DIO (so we can save some pointless io_end allocations) and we pass pointer to it in bh->b_private which generic DIO code later passes to our end IO callback. That way we remove any need for global pointer to io_end structure and thus fix the races. The downside of this change is that the checking for unwritten IO in flight in ext4_extents_can_be_merged() is more racy since we now increment i_unwritten / set EXT4_STATE_DIO_UNWRITTEN only after dropping i_data_sem. However the check has been racy already before because ext4_writepages() already increment i_unwritten after dropping i_data_sem and reserved blocks save us from hitting ENOSPC in the worst case. Signed-off-by: Jan Kara <jack@suse.cz>
* ext4: trim unused parameter from convert_initialized_extent()Eric Whitney2016-02-221-2/+2
| | | | | | | The flags parameter is also unused. Signed-off-by: Eric Whitney <enwlinux@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: remove unused parameter "newblock" in convert_initialized_extent()Eryu Guan2016-02-121-2/+2
| | | | | | | | The "newblock" parameter is not used in convert_initialized_extent(), remove it. Signed-off-by: Eryu Guan <guaneryu@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* wrappers for ->i_mutex accessAl Viro2016-01-221-10/+10
| | | | | | | | | | | parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* ext4: implement allocation of pre-zeroed blocksJan Kara2015-12-071-0/+8
| | | | | | | | | DAX page fault path needs to get blocks that are pre-zeroed to avoid races when two concurrent page faults happen in the same block of a file. Implement support for this in ext4_map_blocks(). Signed-off-by: Jan Kara <jack@suse.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: provide ext4_issue_zeroout()Jan Kara2015-12-071-10/+2
| | | | | | | | | | Create new function ext4_issue_zeroout() to zeroout contiguous (both logically and physically) part of inode data. We will need to issue zeroout when extent structure is not readily available and this function will allow us to do it without making up fake extent structures. Signed-off-by: Jan Kara <jack@suse.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: fix races of writeback with punch hole and zero rangeJan Kara2015-12-071-0/+5
| | | | | | | | | | | | | When doing delayed allocation, update of on-disk inode size is postponed until IO submission time. However hole punch or zero range fallocate calls can end up discarding the tail page cache page and thus on-disk inode size would never be properly updated. Make sure the on-disk inode size is updated before truncating page cache. Signed-off-by: Jan Kara <jack@suse.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: fix races between buffered IO and collapse / insert rangeJan Kara2015-12-071-28/+31
| | | | | | | | | | | | | | | | Current code implementing FALLOC_FL_COLLAPSE_RANGE and FALLOC_FL_INSERT_RANGE is prone to races with buffered writes and page faults. If buffered write or write via mmap manages to squeeze between filemap_write_and_wait_range() and truncate_pagecache() in the fallocate implementations, the written data is simply discarded by truncate_pagecache() although it should have been shifted. Fix the problem by moving filemap_write_and_wait_range() call inside i_mutex and i_mmap_sem. That way we are protected against races with both buffered writes and page faults. Signed-off-by: Jan Kara <jack@suse.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: move unlocked dio protection from ext4_alloc_file_blocks()Jan Kara2015-12-071-11/+10
| | | | | | | | | | | | | | Currently ext4_alloc_file_blocks() was handling protection against unlocked DIO. However we now need to sometimes call it under i_mmap_sem and sometimes not and DIO protection ranks above it (although strictly speaking this cannot currently create any deadlocks). Also ext4_zero_range() was actually getting & releasing unlocked DIO protection twice in some cases. Luckily it didn't introduce any real bug but it was a land mine waiting to be stepped on. So move DIO protection out from ext4_alloc_file_blocks() into the two callsites. Signed-off-by: Jan Kara <jack@suse.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: fix races between page faults and hole punchingJan Kara2015-12-071-24/+30
| | | | | | | | | | | | | | | | | | | | | | Currently, page faults and hole punching are completely unsynchronized. This can result in page fault faulting in a page into a range that we are punching after truncate_pagecache_range() has been called and thus we can end up with a page mapped to disk blocks that will be shortly freed. Filesystem corruption will shortly follow. Note that the same race is avoided for truncate by checking page fault offset against i_size but there isn't similar mechanism available for punching holes. Fix the problem by creating new rw semaphore i_mmap_sem in inode and grab it for writing over truncate, hole punching, and other functions removing blocks from extent tree and for read over page faults. We cannot easily use i_data_sem for this since that ranks below transaction start and we need something ranking above it so that it can be held over the whole truncate / hole punching operation. Also remove various workarounds we had in the code to reduce race window when page fault could have created pages with stale mapping information. Signed-off-by: Jan Kara <jack@suse.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* Merge branch 'for-linus' of ↵Linus Torvalds2015-11-071-3/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial updates from Jiri Kosina: "Trivial stuff from trivial tree that can be trivially summed up as: - treewide drop of spurious unlikely() before IS_ERR() from Viresh Kumar - cosmetic fixes (that don't really affect basic functionality of the driver) for pktcdvd and bcache, from Julia Lawall and Petr Mladek - various comment / printk fixes and updates all over the place" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: bcache: Really show state of work pending bit hwmon: applesmc: fix comment typos Kconfig: remove comment about scsi_wait_scan module class_find_device: fix reference to argument "match" debugfs: document that debugfs_remove*() accepts NULL and error values net: Drop unlikely before IS_ERR(_OR_NULL) mm: Drop unlikely before IS_ERR(_OR_NULL) fs: Drop unlikely before IS_ERR(_OR_NULL) drivers: net: Drop unlikely before IS_ERR(_OR_NULL) drivers: misc: Drop unlikely before IS_ERR(_OR_NULL) UBI: Update comments to reflect UBI_METAONLY flag pktcdvd: drop null test before destroy functions
OpenPOWER on IntegriCloud