kernel/linux.git/fs/ext4/fast_commit.h, branch v6.6.132

ext4: add missing validation of fast-commit record lengths

2022-12-09T02:49:24+00:00

Validate the inode and filename lengths in fast-commit journal records so that a malicious fast-commit journal cannot cause a crash by having invalid values for these. Also validate EXT4_FC_TAG_DEL_RANGE. Fixes: aa75f4d3daae ("ext4: main fast-commit commit path") Cc: # v5.10+ Signed-off-by: Eric Biggers Link: https://lore.kernel.org/r/20221106224841.279231-5-ebiggers@kernel.org Signed-off-by: Theodore Ts'o

ext4: disable fast-commit of encrypted dir operations

2022-12-09T02:49:24+00:00

fast-commit of create, link, and unlink operations in encrypted directories is completely broken because the unencrypted filenames are being written to the fast-commit journal instead of the encrypted filenames. These operations can't be replayed, as encryption keys aren't present at journal replay time. It is also an information leak. Until if/when we can get this working properly, make encrypted directory operations ineligible for fast-commit. Note that fast-commit operations on encrypted regular files continue to be allowed, as they seem to work. Fixes: aa75f4d3daae ("ext4: main fast-commit commit path") Cc: # v5.10+ Signed-off-by: Eric Biggers Link: https://lore.kernel.org/r/20221106224841.279231-2-ebiggers@kernel.org Signed-off-by: Theodore Ts'o

ext4: introduce EXT4_FC_TAG_BASE_LEN helper

2022-10-01T03:46:54+00:00

Introduce EXT4_FC_TAG_BASE_LEN helper for calculate length of struct ext4_fc_tl. Signed-off-by: Ye Bin Link: https://lore.kernel.org/r/20220924075233.2315259-2-yebin10@huawei.com Signed-off-by: Theodore Ts'o

Merge tag 'flexible-array-transformations-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux

2022-03-24T18:39:32+00:00

Pull flexible-array transformations from Gustavo Silva: "Treewide patch that replaces zero-length arrays with flexible-array members. This has been baking in linux-next for a whole development cycle" * tag 'flexible-array-transformations-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux: treewide: Replace zero-length arrays with flexible-array members

ext4: remove unused enum EXT4_FC_COMMIT_FAILED

2022-03-13T02:26:08+00:00

Below commit removed all references of EXT4_FC_COMMIT_FAILED. commit 0915e464cb274 ("ext4: simplify updating of fast commit stats") Just remove it since it is not used anymore. Signed-off-by: Ritesh Harjani Reviewed-by: Jan Kara Reviewed-by: Harshad Shirwadkar Link: https://lore.kernel.org/r/c941357e476be07a1138c7319ca5faab7fb80fc6.1647057583.git.riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o

ext4: improve fast_commit performance and scalability

2022-03-03T04:11:15+00:00

Currently ext4_fc_commit_dentry_updates() is of quadratic time complexity, which is causing performance bottlenecks with high threads/file/dir count with fs_mark. This patch makes commit dentry updates (and hence ext4_fc_commit()) path to linear time complexity. Hence improves the performance of workloads which does fsync on multiple threads/open files one-by-one. Absolute numbers in avg file creates per sec (from fs_mark in 1K order) ======================================================================= no. Order without-patch(K) with-patch(K) Diff(%) 1 1 16.90 17.51 +3.60 2 2,2 32.08 31.80 -0.87 3 3,3 53.97 55.01 +1.92 4 4,4 78.94 76.90 -2.58 5 5,5 95.82 95.37 -0.46 6 6,6 87.92 103.38 +17.58 7 6,10 0.73 126.13 +17178.08 8 6,14 2.33 143.19 +6045.49 workload type ============== For e.g. 7th row order of 6,10 (2^6 == 64 && 2^10 == 1024) echo /run/riteshh/mnt/{1..64} |sed -E 's/[[:space:]]+/ -d /g' \ | xargs -I {} bash -c "sudo fs_mark -L 100 -D 1024 -n 1024 -s0 -S5 -d {}" Perf profile (w/o patches) ============================= 87.15% [kernel] [k] ext4_fc_commit --> Heavy contention/bottleneck 1.98% [kernel] [k] perf_event_interrupt 0.96% [kernel] [k] power_pmu_enable 0.91% [kernel] [k] update_sd_lb_stats.constprop.0 0.67% [kernel] [k] ktime_get Signed-off-by: Ritesh Harjani Reviewed-by: Harshad Shirwadkar Link: https://lore.kernel.org/r/930f35d4fd5f83e2673c868781d9ebf15e91bf4e.1645426817.git.riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o

treewide: Replace zero-length arrays with flexible-array members

2022-02-17T13:00:39+00:00

There is a regular need in the kernel to provide a way to declare having a dynamically sized set of trailing elements in a structure. Kernel code should always use “flexible array members”[1] for these cases. The older style of one-element or zero-length arrays should no longer be used[2]. This code was transformed with the help of Coccinelle: (next-20220214$ spatch --jobs $(getconf _NPROCESSORS_ONLN) --sp-file script.cocci --include-headers --dir . > output.patch) @@ identifier S, member, array; type T1, T2; @@ struct S { ... T1 member; T2 array[ - 0 ]; }; UAPI and wireless changes were intentionally excluded from this patch and will be sent out separately. [1] https://en.wikipedia.org/wiki/Flexible_array_member [2] https://www.kernel.org/doc/html/v5.16/process/deprecated.html#zero-length-and-one-element-arrays Link: https://github.com/KSPP/linux/issues/78 Reviewed-by: Kees Cook Signed-off-by: Gustavo A. R. Silva

ext4: simplify updating of fast commit stats

2021-12-23T23:13:25+00:00

Move fast commit stats updating logic to a separate function from ext4_fc_commit(). This significantly improves readability of ext4_fc_commit(). Signed-off-by: Harshad Shirwadkar Link: https://lore.kernel.org/r/20211223202140.2061101-4-harshads@google.com Signed-off-by: Theodore Ts'o

ext4: fix fast commit alignment issues

2021-06-06T14:10:23+00:00

Fast commit recovery data on disk may not be aligned. So, when the recovery code reads it, this patch makes sure that fast commit info found on-disk is first memcpy-ed into an aligned variable before accessing it. As a consequence of it, we also remove some macros that could resulted in unaligned accesses. Cc: stable@kernel.org Fixes: 8016e29f4362 ("ext4: fast commit recovery path") Signed-off-by: Harshad Shirwadkar Link: https://lore.kernel.org/r/20210519215920.2037527-1-harshads@google.com Signed-off-by: Theodore Ts'o

ext4: make fast_commit.h byte identical with e2fsprogs/fast_commit.h

2020-12-17T18:30:45+00:00

This patch makes fast_commit.h byte by byte identical with e2fsprogs/fast_commit.h. This will help us ensure that there are no on-disk format inconsistencies between e2fsck and kernel ext4. Signed-off-by: Harshad Shirwadkar Link: https://lore.kernel.org/r/20201120202232.2240293-1-harshadshirwadkar@gmail.com Signed-off-by: Theodore Ts'o