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2020-08-21Merge tag 'ext4_for_linus' of ↵Linus Torvalds1-10/+13
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "Improvements to ext4's block allocator performance for very large file systems, especially when the file system or files which are highly fragmented. There is a new mount option, prefetch_block_bitmaps which will pull in the block bitmaps and set up the in-memory buddy bitmaps when the file system is initially mounted. Beyond that, a lot of bug fixes and cleanups. In particular, a number of changes to make ext4 more robust in the face of write errors or file system corruptions" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (46 commits) ext4: limit the length of per-inode prealloc list ext4: reorganize if statement of ext4_mb_release_context() ext4: add mb_debug logging when there are lost chunks ext4: Fix comment typo "the the". jbd2: clean up checksum verification in do_one_pass() ext4: change to use fallthrough macro ext4: remove unused parameter of ext4_generic_delete_entry function mballoc: replace seq_printf with seq_puts ext4: optimize the implementation of ext4_mb_good_group() ext4: delete invalid comments near ext4_mb_check_limits() ext4: fix typos in ext4_mb_regular_allocator() comment ext4: fix checking of directory entry validity for inline directories fs: prevent BUG_ON in submit_bh_wbc() ext4: correctly restore system zone info when remount fails ext4: handle add_system_zone() failure in ext4_setup_system_zone() ext4: fold ext4_data_block_valid_rcu() into the caller ext4: check journal inode extents more carefully ext4: don't allow overlapping system zones ext4: handle error of ext4_setup_system_zone() on remount ext4: delete the invalid BUGON in ext4_mb_load_buddy_gfp() ...
2020-08-19ext4: limit the length of per-inode prealloc listbrookxu1-0/+3
In the scenario of writing sparse files, the per-inode prealloc list may be very long, resulting in high overhead for ext4_mb_use_preallocated(). To circumvent this problem, we limit the maximum length of per-inode prealloc list to 512 and allow users to modify it. After patching, we observed that the sys ratio of cpu has dropped, and the system throughput has increased significantly. We created a process to write the sparse file, and the running time of the process on the fixed kernel was significantly reduced, as follows: Running time on unfixed kernel: [root@TENCENT64 ~]# time taskset 0x01 ./sparse /data1/sparce.dat real 0m2.051s user 0m0.008s sys 0m2.026s Running time on fixed kernel: [root@TENCENT64 ~]# time taskset 0x01 ./sparse /data1/sparce.dat real 0m0.471s user 0m0.004s sys 0m0.395s Signed-off-by: Chunguang Xu <brookxu@tencent.com> Link: https://lore.kernel.org/r/d7a98178-056b-6db5-6bce-4ead23f4a257@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-08-06ext4: use generic names for generic ioctlsEric Biggers1-10/+10
Don't define EXT4_IOC_* aliases to ioctls that already have a generic FS_IOC_* name. These aliases are unnecessary, and they make it unclear which ioctls are ext4-specific and which are generic. Exception: leave EXT4_IOC_GETVERSION_OLD and EXT4_IOC_SETVERSION_OLD as-is for now, since renaming them to FS_IOC_GETVERSION and FS_IOC_SETVERSION would probably make them more likely to be confused with EXT4_IOC_GETVERSION and EXT4_IOC_SETVERSION which also exist. Signed-off-by: Eric Biggers <ebiggers@google.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20200714230909.56349-1-ebiggers@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-08-05Merge tag 'docs-5.9' of git://git.lwn.net/linuxLinus Torvalds1-2/+2
Pull documentation updates from Jonathan Corbet: "It's been a busy cycle for documentation - hopefully the busiest for a while to come. Changes include: - Some new Chinese translations - Progress on the battle against double words words and non-HTTPS URLs - Some block-mq documentation - More RST conversions from Mauro. At this point, that task is essentially complete, so we shouldn't see this kind of churn again for a while. Unless we decide to switch to asciidoc or something...:) - Lots of typo fixes, warning fixes, and more" * tag 'docs-5.9' of git://git.lwn.net/linux: (195 commits) scripts/kernel-doc: optionally treat warnings as errors docs: ia64: correct typo mailmap: add entry for <alobakin@marvell.com> doc/zh_CN: add cpu-load Chinese version Documentation/admin-guide: tainted-kernels: fix spelling mistake MAINTAINERS: adjust kprobes.rst entry to new location devices.txt: document rfkill allocation PCI: correct flag name docs: filesystems: vfs: correct flag name docs: filesystems: vfs: correct sync_mode flag names docs: path-lookup: markup fixes for emphasis docs: path-lookup: more markup fixes docs: path-lookup: fix HTML entity mojibake CREDITS: Replace HTTP links with HTTPS ones docs: process: Add an example for creating a fixes tag doc/zh_CN: add Chinese translation prefer section doc/zh_CN: add clearing-warn-once Chinese version doc/zh_CN: add admin-guide index doc:it_IT: process: coding-style.rst: Correct __maybe_unused compiler label futex: MAINTAINERS: Re-add selftests directory ...
2020-07-08ext4: add inline encryption supportEric Biggers1-0/+7
Wire up ext4 to support inline encryption via the helper functions which fs/crypto/ now provides. This includes: - Adding a mount option 'inlinecrypt' which enables inline encryption on encrypted files where it can be used. - Setting the bio_crypt_ctx on bios that will be submitted to an inline-encrypted file. Note: submit_bh_wbc() in fs/buffer.c also needed to be patched for this part, since ext4 sometimes uses ll_rw_block() on file data. - Not adding logically discontiguous data to bios that will be submitted to an inline-encrypted file. - Not doing filesystem-layer crypto on inline-encrypted files. Co-developed-by: Satya Tangirala <satyat@google.com> Signed-off-by: Satya Tangirala <satyat@google.com> Reviewed-by: Theodore Ts'o <tytso@mit.edu> Link: https://lore.kernel.org/r/20200702015607.1215430-5-satyat@google.com Signed-off-by: Eric Biggers <ebiggers@google.com>
2020-07-05Replace HTTP links with HTTPS ones: Documentation/admin-guideAlexander A. Klimov1-2/+2
Rationale: Reduces attack surface on kernel devs opening the links for MITM as HTTPS traffic is much harder to manipulate. Deterministic algorithm: For each file: If not .svg: For each line: If doesn't contain `\bxmlns\b`: For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`: If both the HTTP and HTTPS versions return 200 OK and serve the same content: Replace HTTP with HTTPS. Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de> Link: https://lore.kernel.org/r/20200627072935.62652-1-grandmaster@al2klimov.de Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-01-18docs: ext4.rst: add encryption and verity to features listEric Biggers1-0/+2
Mention encryption and verity in the ext4 features list. Signed-off-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20191226154007.4569-1-ebiggers@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-12-22ext4: clarify impact of 'commit' mount optionJan Kara1-8/+11
The description of 'commit' mount option dates back to ext3 times. Update the description to match current meaning for ext4. Reported-by: Paul Richards <paul.richards@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20191218111210.14161-1-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-04-25docs: ext4.rst: document case-insensitive directoriesGabriel Krisman Bertazi1-0/+38
Introduces the case-insensitive features on ext4 for system administrators. Explain the minimum of design decisions that are important for sysadmins wanting to enable this feature. Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2018-10-06docs: move ext4 administrative docs to admin-guide/Darrick J. Wong1-0/+574
Move the ext4 mount option and other administrative stuff to the Linux administrator's guide. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>