BMC/Intel-BMC/linux.git/fs/btrfs/sysfs.c, branch dev-4.17

btrfs: replace GPL boilerplate by SPDX -- sources

2018-04-12T14:29:51+00:00

Remove GPL boilerplate text (long, short, one-line) and keep the rest, ie. personal, company or original source copyright statements. Add the SPDX header. Signed-off-by: David Sterba

btrfs: defer adding raid type kobject until after chunk relocation

2018-03-30T23:41:12+00:00

Any time the first block group of a new type is created, we add a new kobject to sysfs to hold the attributes for that type. Kobject-internal allocations always use GFP_KERNEL, making them prone to fs-reclaim races. While it appears as if this can occur any time a block group is created, the only times the first block group of a new type can be created in memory is at mount and when we create the first new block group during raid conversion. This patch adds a new list to track pending kobject additions and then handles them after we do chunk relocation. Between relocating the target chunk (or forcing allocation of a new chunk in the case of data) and removing the old chunk, we're in a safe place for fs-reclaim to occur. We're holding the volume mutex, which is already held across page faults, and the delete_unused_bgs_mutex, which will only stall the cleaner thread. Signed-off-by: Jeff Mahoney Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: add more __cold annotations

2018-03-26T13:09:39+00:00

The __cold functions are placed to a special section, as they're expected to be called rarely. This could help i-cache prefetches or help compiler to decide which branches are more/less likely to be taken without any other annotations needed. Though we can't add more __exit annotations, it's still possible to add __cold (that's also added with __exit). That way the following function categories are tagged: - printf wrappers, error messages - exit helpers Signed-off-by: David Sterba

Revert "btrfs: use proper endianness accessors for super_copy"

2018-03-16T13:49:44+00:00

This reverts commit 3c181c12c431fe33b669410d663beb9cceefcd1b. The offending patch was merged in 4.16-rc4 and was promptly applied to stable kernels 4.14.25 and 4.15.8. The patch causes a corruption in several superblock items on big-endian machines because of messed up endianity conversions. The damage is manually repairable. A filesystem cannot be mounted again after it has been unmounted once. We do a full revert and not a fixup so stable can pick that patch ASAP. Fixes: 3c181c12c431 ("btrfs: use proper endianness accessors for super_copy") Link: https://lkml.kernel.org/r/1521139304@msgid.manchmal.in-ulm.de CC: stable@vger.kernel.org # 4.14+ Reported-by: Christoph Biedl Signed-off-by: David Sterba

btrfs: use proper endianness accessors for super_copy

2018-03-01T15:17:27+00:00

The fs_info::super_copy is a byte copy of the on-disk structure and all members must use the accessor macros/functions to obtain the right value. This was missing in update_super_roots and in sysfs readers. Moving between opposite endianness hosts will report bogus numbers in sysfs, and mount may fail as the root will not be restored correctly. If the filesystem is always used on a same endian host, this will not be a problem. Fix this by using the btrfs_set_super...() functions to set fs_info::super_copy values, and for the sysfs, use the cached fs_info::nodesize/sectorsize values. CC: stable@vger.kernel.org Fixes: df93589a17378 ("btrfs: export more from FS_INFO to sysfs") Signed-off-by: Anand Jain Reviewed-by: Liu Bo Reviewed-by: David Sterba [ update changelog ] Signed-off-by: David Sterba

Btrfs: add __init macro to btrfs init functions

2018-01-22T15:08:11+00:00

Adding __init macro gives kernel a hint that this function is only used during the initialization phase and its memory resources can be freed up after. Signed-off-by: Liu Bo Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: prefix sysfs attribute struct names

2017-10-30T11:27:58+00:00

Currently struct names for sysfs are generated only based on the attribute names. This means that attribute names cannot be reused in multiple places throughout the complete btrfs sysfs hierarchy. E.g. allocation/data/total_bytes and allocation/data/single/total_bytes result in the same struct name btrfs_attr_total_bytes. A workaround for this case was made in the past by ad hoc creating an extra macro wrapper, BTRFS_RAID_ATTR, that inserts some extra text in the struct name. Instead of polluting sysfs.h with such kind of extra macro definitions, and only doing so when there are collisions, use a prefix which gets inserted in the struct name, so we keep everything nicely grouped together by default. Current collections of attributes are: * (the toplevel, empty prefix) * allocation * space_info * raid * features Signed-off-by: Hans van Kranenburg Reviewed-by: David Sterba Signed-off-by: David Sterba

Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2017-09-15T01:54:01+00:00

Pull mount flag updates from Al Viro: "Another chunk of fmount preparations from dhowells; only trivial conflicts for that part. It separates MS_... bits (very grotty mount(2) ABI) from the struct super_block ->s_flags (kernel-internal, only a small subset of MS_... stuff). This does *not* convert the filesystems to new constants; only the infrastructure is done here. The next step in that series is where the conflicts would be; that's the conversion of filesystems. It's purely mechanical and it's better done after the merge, so if you could run something like list=$(for i in MS_RDONLY MS_NOSUID MS_NODEV MS_NOEXEC MS_SYNCHRONOUS MS_MANDLOCK MS_DIRSYNC MS_NOATIME MS_NODIRATIME MS_SILENT MS_POSIXACL MS_KERNMOUNT MS_I_VERSION MS_LAZYTIME; do git grep -l $i fs drivers/staging/lustre drivers/mtd ipc mm include/linux; done|sort|uniq|grep -v '^fs/namespace.c$') sed -i -e 's/\/SB_RDONLY/g' \ -e 's/\/SB_NOSUID/g' \ -e 's/\/SB_NODEV/g' \ -e 's/\/SB_NOEXEC/g' \ -e 's/\/SB_SYNCHRONOUS/g' \ -e 's/\/SB_MANDLOCK/g' \ -e 's/\/SB_DIRSYNC/g' \ -e 's/\/SB_NOATIME/g' \ -e 's/\/SB_NODIRATIME/g' \ -e 's/\/SB_SILENT/g' \ -e 's/\/SB_POSIXACL/g' \ -e 's/\/SB_KERNMOUNT/g' \ -e 's/\/SB_I_VERSION/g' \ -e 's/\/SB_LAZYTIME/g' \ $list and commit it with something along the lines of 'convert filesystems away from use of MS_... constants' as commit message, it would save a quite a bit of headache next cycle" * 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: VFS: Differentiate mount flags (MS_*) from internal superblock flags VFS: Convert sb->s_flags & MS_RDONLY to sb_rdonly(sb) vfs: Add sb_rdonly(sb) to query the MS_RDONLY flag on s_flags

btrfs: Add zstd support

2017-08-15T16:02:09+00:00

Add zstd compression and decompression support to BtrFS. zstd at its fastest level compresses almost as well as zlib, while offering much faster compression and decompression, approaching lzo speeds. I benchmarked btrfs with zstd compression against no compression, lzo compression, and zlib compression. I benchmarked two scenarios. Copying a set of files to btrfs, and then reading the files. Copying a tarball to btrfs, extracting it to btrfs, and then reading the extracted files. After every operation, I call `sync` and include the sync time. Between every pair of operations I unmount and remount the filesystem to avoid caching. The benchmark files can be found in the upstream zstd source repository under `contrib/linux-kernel/{btrfs-benchmark.sh,btrfs-extract-benchmark.sh}` [1] [2]. I ran the benchmarks on a Ubuntu 14.04 VM with 2 cores and 4 GiB of RAM. The VM is running on a MacBook Pro with a 3.1 GHz Intel Core i7 processor, 16 GB of RAM, and a SSD. The first compression benchmark is copying 10 copies of the unzipped Silesia corpus [3] into a BtrFS filesystem mounted with `-o compress-force=Method`. The decompression benchmark times how long it takes to `tar` all 10 copies into `/dev/null`. The compression ratio is measured by comparing the output of `df` and `du`. See the benchmark file [1] for details. I benchmarked multiple zstd compression levels, although the patch uses zstd level 1. | Method | Ratio | Compression MB/s | Decompression speed | |---------|-------|------------------|---------------------| | None | 0.99 | 504 | 686 | | lzo | 1.66 | 398 | 442 | | zlib | 2.58 | 65 | 241 | | zstd 1 | 2.57 | 260 | 383 | | zstd 3 | 2.71 | 174 | 408 | | zstd 6 | 2.87 | 70 | 398 | | zstd 9 | 2.92 | 43 | 406 | | zstd 12 | 2.93 | 21 | 408 | | zstd 15 | 3.01 | 11 | 354 | The next benchmark first copies `linux-4.11.6.tar` [4] to btrfs. Then it measures the compression ratio, extracts the tar, and deletes the tar. Then it measures the compression ratio again, and `tar`s the extracted files into `/dev/null`. See the benchmark file [2] for details. | Method | Tar Ratio | Extract Ratio | Copy (s) | Extract (s)| Read (s) | |--------|-----------|---------------|----------|------------|----------| | None | 0.97 | 0.78 | 0.981 | 5.501 | 8.807 | | lzo | 2.06 | 1.38 | 1.631 | 8.458 | 8.585 | | zlib | 3.40 | 1.86 | 7.750 | 21.544 | 11.744 | | zstd 1 | 3.57 | 1.85 | 2.579 | 11.479 | 9.389 | [1] https://github.com/facebook/zstd/blob/dev/contrib/linux-kernel/btrfs-benchmark.sh [2] https://github.com/facebook/zstd/blob/dev/contrib/linux-kernel/btrfs-extract-benchmark.sh [3] http://sun.aei.polsl.pl/~sdeor/index.php?page=silesia [4] https://cdn.kernel.org/pub/linux/kernel/v4.x/linux-4.11.6.tar.xz zstd source repository: https://github.com/facebook/zstd Signed-off-by: Nick Terrell Signed-off-by: Chris Mason

VFS: Convert sb->s_flags & MS_RDONLY to sb_rdonly(sb)

2017-07-17T07:45:34+00:00

Firstly by applying the following with coccinelle's spatch: @@ expression SB; @@ -SB->s_flags & MS_RDONLY +sb_rdonly(SB) to effect the conversion to sb_rdonly(sb), then by applying: @@ expression A, SB; @@ ( -(!sb_rdonly(SB)) && A +!sb_rdonly(SB) && A | -A != (sb_rdonly(SB)) +A != sb_rdonly(SB) | -A == (sb_rdonly(SB)) +A == sb_rdonly(SB) | -!(sb_rdonly(SB)) +!sb_rdonly(SB) | -A && (sb_rdonly(SB)) +A && sb_rdonly(SB) | -A || (sb_rdonly(SB)) +A || sb_rdonly(SB) | -(sb_rdonly(SB)) != A +sb_rdonly(SB) != A | -(sb_rdonly(SB)) == A +sb_rdonly(SB) == A | -(sb_rdonly(SB)) && A +sb_rdonly(SB) && A | -(sb_rdonly(SB)) || A +sb_rdonly(SB) || A ) @@ expression A, B, SB; @@ ( -(sb_rdonly(SB)) ? 1 : 0 +sb_rdonly(SB) | -(sb_rdonly(SB)) ? A : B +sb_rdonly(SB) ? A : B ) to remove left over excess bracketage and finally by applying: @@ expression A, SB; @@ ( -(A & MS_RDONLY) != sb_rdonly(SB) +(bool)(A & MS_RDONLY) != sb_rdonly(SB) | -(A & MS_RDONLY) == sb_rdonly(SB) +(bool)(A & MS_RDONLY) == sb_rdonly(SB) ) to make comparisons against the result of sb_rdonly() (which is a bool) work correctly. Signed-off-by: David Howells