1. 02 Aug, 2018 2 commits
  2. 01 Aug, 2018 1 commit
    • Linus Torvalds's avatar
      squashfs metadata 2: electric boogaloo · cdbb65c4
      Linus Torvalds authored
      Anatoly continues to find issues with fuzzed squashfs images.
      
      This time, corrupt, missing, or undersized data for the page filling
      wasn't checked for, because the squashfs_{copy,read}_cache() functions
      did the squashfs_copy_data() call without checking the resulting data
      size.
      
      Which could result in the page cache pages being incompletely filled in,
      and no error indication to the user space reading garbage data.
      
      So make a helper function for the "fill in pages" case, because the
      exact same incomplete sequence existed in two places.
      
      [ I should have made a squashfs branch for these things, but I didn't
        intend to start doing them in the first place.
      
        My historical connection through cramfs is why I got into looking at
        these issues at all, and every time I (continue to) think it's a
        one-off.
      
        Because _this_ time is always the last time. Right?   - Linus ]
      Reported-by: 's avatarAnatoly Trosinenko <anatoly.trosinenko@gmail.com>
      Tested-by: 's avatarWilly Tarreau <w@1wt.eu>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: Phillip Lougher <phillip@squashfs.org.uk>
      Signed-off-by: 's avatarLinus Torvalds <torvalds@linux-foundation.org>
      cdbb65c4
  3. 31 Jul, 2018 1 commit
  4. 29 Jul, 2018 1 commit
  5. 27 Nov, 2017 1 commit
    • Linus Torvalds's avatar
      Rename superblock flags (MS_xyz -> SB_xyz) · 1751e8a6
      Linus Torvalds authored
      This is a pure automated search-and-replace of the internal kernel
      superblock flags.
      
      The s_flags are now called SB_*, with the names and the values for the
      moment mirroring the MS_* flags that they're equivalent to.
      
      Note how the MS_xyz flags are the ones passed to the mount system call,
      while the SB_xyz flags are what we then use in sb->s_flags.
      
      The script to do this was:
      
          # places to look in; re security/*: it generally should *not* be
          # touched (that stuff parses mount(2) arguments directly), but
          # there are two places where we really deal with superblock flags.
          FILES="drivers/mtd drivers/staging/lustre fs ipc mm \
                  include/linux/fs.h include/uapi/linux/bfs_fs.h \
                  security/apparmor/apparmorfs.c security/apparmor/include/lib.h"
          # the list of MS_... constants
          SYMS="RDONLY NOSUID NODEV NOEXEC SYNCHRONOUS REMOUNT MANDLOCK \
                DIRSYNC NOATIME NODIRATIME BIND MOVE REC VERBOSE SILENT \
                POSIXACL UNBINDABLE PRIVATE SLAVE SHARED RELATIME KERNMOUNT \
                I_VERSION STRICTATIME LAZYTIME SUBMOUNT NOREMOTELOCK NOSEC BORN \
                ACTIVE NOUSER"
      
          SED_PROG=
          for i in $SYMS; do SED_PROG="$SED_PROG -e s/MS_$i/SB_$i/g"; done
      
          # we want files that contain at least one of MS_...,
          # with fs/namespace.c and fs/pnode.c excluded.
          L=$(for i in $SYMS; do git grep -w -l MS_$i $FILES; done| sort|uniq|grep -v '^fs/namespace.c'|grep -v '^fs/pnode.c')
      
          for f in $L; do sed -i $f $SED_PROG; done
      Requested-by: 's avatarAl Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: 's avatarLinus Torvalds <torvalds@linux-foundation.org>
      1751e8a6
  6. 02 Nov, 2017 1 commit
    • Greg Kroah-Hartman's avatar
      License cleanup: add SPDX GPL-2.0 license identifier to files with no license · b2441318
      Greg Kroah-Hartman authored
      Many source files in the tree are missing licensing information, which
      makes it harder for compliance tools to determine the correct license.
      
      By default all files without license information are under the default
      license of the kernel, which is GPL version 2.
      
      Update the files which contain no license information with the 'GPL-2.0'
      SPDX license identifier.  The SPDX identifier is a legally binding
      shorthand, which can be used instead of the full boiler plate text.
      
      This patch is based on work done by Thomas Gleixner and Kate Stewart and
      Philippe Ombredanne.
      
      How this work was done:
      
      Patches were generated and checked against linux-4.14-rc6 for a subset of
      the use cases:
       - file had no licensing information it it.
       - file was a */uapi/* one with no licensing information in it,
       - file was a */uapi/* one with existing licensing information,
      
      Further patches will be generated in subsequent months to fix up cases
      where non-standard license headers were used, and references to license
      had to be inferred by heuristics based on keywords.
      
      The analysis to determine which SPDX License Identifier to be applied to
      a file was done in a spreadsheet of side by side results from of the
      output of two independent scanners (ScanCode & Windriver) producing SPDX
      tag:value files created by Philippe Ombredanne.  Philippe prepared the
      base worksheet, and did an initial spot review of a few 1000 files.
      
      The 4.13 kernel was the starting point of the analysis with 60,537 files
      assessed.  Kate Stewart did a file by file comparison of the scanner
      results in the spreadsheet to determine which SPDX license identifier(s)
      to be applied to the file. She confirmed any determination that was not
      immediately clear with lawyers working with the Linux Foundation.
      
      Criteria used to select files for SPDX license identifier tagging was:
       - Files considered eligible had to be source code files.
       - Make and config files were included as candidates if they contained >5
         lines of source
       - File already had some variant of a license header in it (even if <5
         lines).
      
      All documentation files were explicitly excluded.
      
      The following heuristics were used to determine which SPDX license
      identifiers to apply.
      
       - when both scanners couldn't find any license traces, file was
         considered to have no license information in it, and the top level
         COPYING file license applied.
      
         For non */uapi/* files that summary was:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|-------
         GPL-2.0                                              11139
      
         and resulted in the first patch in this series.
      
         If that file was a */uapi/* path one, it was "GPL-2.0 WITH
         Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|-------
         GPL-2.0 WITH Linux-syscall-note                        930
      
         and resulted in the second patch in this series.
      
       - if a file had some form of licensing information in it, and was one
         of the */uapi/* ones, it was denoted with the Linux-syscall-note if
         any GPL family license was found in the file or had no licensing in
         it (per prior point).  Results summary:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|------
         GPL-2.0 WITH Linux-syscall-note                       270
         GPL-2.0+ WITH Linux-syscall-note                      169
         ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
         ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
         LGPL-2.1+ WITH Linux-syscall-note                      15
         GPL-1.0+ WITH Linux-syscall-note                       14
         ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
         LGPL-2.0+ WITH Linux-syscall-note                       4
         LGPL-2.1 WITH Linux-syscall-note                        3
         ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
         ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1
      
         and that resulted in the third patch in this series.
      
       - when the two scanners agreed on the detected license(s), that became
         the concluded license(s).
      
       - when there was disagreement between the two scanners (one detected a
         license but the other didn't, or they both detected different
         licenses) a manual inspection of the file occurred.
      
       - In most cases a manual inspection of the information in the file
         resulted in a clear resolution of the license that should apply (and
         which scanner probably needed to revisit its heuristics).
      
       - When it was not immediately clear, the license identifier was
         confirmed with lawyers working with the Linux Foundation.
      
       - If there was any question as to the appropriate license identifier,
         the file was flagged for further research and to be revisited later
         in time.
      
      In total, over 70 hours of logged manual review was done on the
      spreadsheet to determine the SPDX license identifiers to apply to the
      source files by Kate, Philippe, Thomas and, in some cases, confirmation
      by lawyers working with the Linux Foundation.
      
      Kate also obtained a third independent scan of the 4.13 code base from
      FOSSology, and compared selected files where the other two scanners
      disagreed against that SPDX file, to see if there was new insights.  The
      Windriver scanner is based on an older version of FOSSology in part, so
      they are related.
      
      Thomas did random spot checks in about 500 files from the spreadsheets
      for the uapi headers and agreed with SPDX license identifier in the
      files he inspected. For the non-uapi files Thomas did random spot checks
      in about 15000 files.
      
      In initial set of patches against 4.14-rc6, 3 files were found to have
      copy/paste license identifier errors, and have been fixed to reflect the
      correct identifier.
      
      Additionally Philippe spent 10 hours this week doing a detailed manual
      inspection and review of the 12,461 patched files from the initial patch
      version early this week with:
       - a full scancode scan run, collecting the matched texts, detected
         license ids and scores
       - reviewing anything where there was a license detected (about 500+
         files) to ensure that the applied SPDX license was correct
       - reviewing anything where there was no detection but the patch license
         was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
         SPDX license was correct
      
      This produced a worksheet with 20 files needing minor correction.  This
      worksheet was then exported into 3 different .csv files for the
      different types of files to be modified.
      
      These .csv files were then reviewed by Greg.  Thomas wrote a script to
      parse the csv files and add the proper SPDX tag to the file, in the
      format that the file expected.  This script was further refined by Greg
      based on the output to detect more types of files automatically and to
      distinguish between header and source .c files (which need different
      comment types.)  Finally Greg ran the script using the .csv files to
      generate the patches.
      Reviewed-by: 's avatarKate Stewart <kstewart@linuxfoundation.org>
      Reviewed-by: 's avatarPhilippe Ombredanne <pombredanne@nexb.com>
      Reviewed-by: 's avatarThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: 's avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b2441318
  7. 09 Sep, 2017 1 commit
    • Sean Purcell's avatar
      squashfs: Add zstd support · 87bf54bb
      Sean Purcell authored
      Add zstd compression and decompression support to SquashFS. zstd is a
      great fit for SquashFS because it can compress at ratios approaching xz,
      while decompressing twice as fast as zlib. For SquashFS in particular,
      it can decompress as fast as lzo and lz4. It also has the flexibility
      to turn down the compression ratio for faster compression times.
      
      The compression benchmark is run on the file tree from the SquashFS archive
      found in ubuntu-16.10-desktop-amd64.iso [1]. It uses `mksquashfs` with the
      default block size (128 KB) and and various compression algorithms/levels.
      xz and zstd are also benchmarked with 256 KB blocks. The decompression
      benchmark times how long it takes to `tar` the file tree into `/dev/null`.
      See the benchmark file in the upstream zstd source repository located under
      `contrib/linux-kernel/squashfs-benchmark.sh` [2] for details.
      
      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.
      
      | Method         | Ratio | Compression MB/s | Decompression MB/s |
      |----------------|-------|------------------|--------------------|
      | gzip           |  2.92 |               15 |                128 |
      | lzo            |  2.64 |              9.5 |                217 |
      | lz4            |  2.12 |               94 |                218 |
      | xz             |  3.43 |              5.5 |                 35 |
      | xz 256 KB      |  3.53 |              5.4 |                 40 |
      | zstd 1         |  2.71 |               96 |                210 |
      | zstd 5         |  2.93 |               69 |                198 |
      | zstd 10        |  3.01 |               41 |                225 |
      | zstd 15        |  3.13 |             11.4 |                224 |
      | zstd 16 256 KB |  3.24 |              8.1 |                210 |
      
      This patch was written by Sean Purcell <me@seanp.xyz>, but I will be
      taking over the submission process.
      
      [1] http://releases.ubuntu.com/16.10/
      [2] https://github.com/facebook/zstd/blob/dev/contrib/linux-kernel/squashfs-benchmark.sh
      
      zstd source repository: https://github.com/facebook/zstdSigned-off-by: 's avatarSean Purcell <me@seanp.xyz>
      Signed-off-by: 's avatarNick Terrell <terrelln@fb.com>
      Signed-off-by: 's avatarChris Mason <clm@fb.com>
      Acked-by: 's avatarPhillip Lougher <phillip@squashfs.org.uk>
      87bf54bb
  8. 25 Feb, 2017 1 commit
  9. 09 Dec, 2016 1 commit
  10. 01 Nov, 2016 1 commit
  11. 08 Oct, 2016 1 commit
  12. 07 Jun, 2016 1 commit
  13. 09 May, 2016 1 commit
  14. 11 Apr, 2016 1 commit
  15. 04 Apr, 2016 2 commits
    • Kirill A. Shutemov's avatar
      mm, fs: remove remaining PAGE_CACHE_* and page_cache_{get,release} usage · ea1754a0
      Kirill A. Shutemov authored
      Mostly direct substitution with occasional adjustment or removing
      outdated comments.
      Signed-off-by: 's avatarKirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Acked-by: 's avatarMichal Hocko <mhocko@suse.com>
      Signed-off-by: 's avatarLinus Torvalds <torvalds@linux-foundation.org>
      ea1754a0
    • Kirill A. Shutemov's avatar
      mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros · 09cbfeaf
      Kirill A. Shutemov authored
      PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
      ago with promise that one day it will be possible to implement page
      cache with bigger chunks than PAGE_SIZE.
      
      This promise never materialized.  And unlikely will.
      
      We have many places where PAGE_CACHE_SIZE assumed to be equal to
      PAGE_SIZE.  And it's constant source of confusion on whether
      PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
      especially on the border between fs and mm.
      
      Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
      breakage to be doable.
      
      Let's stop pretending that pages in page cache are special.  They are
      not.
      
      The changes are pretty straight-forward:
      
       - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
      
       - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
      
       - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};
      
       - page_cache_get() -> get_page();
      
       - page_cache_release() -> put_page();
      
      This patch contains automated changes generated with coccinelle using
      script below.  For some reason, coccinelle doesn't patch header files.
      I've called spatch for them manually.
      
      The only adjustment after coccinelle is revert of changes to
      PAGE_CAHCE_ALIGN definition: we are going to drop it later.
      
      There are few places in the code where coccinelle didn't reach.  I'll
      fix them manually in a separate patch.  Comments and documentation also
      will be addressed with the separate patch.
      
      virtual patch
      
      @@
      expression E;
      @@
      - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
      + E
      
      @@
      expression E;
      @@
      - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
      + E
      
      @@
      @@
      - PAGE_CACHE_SHIFT
      + PAGE_SHIFT
      
      @@
      @@
      - PAGE_CACHE_SIZE
      + PAGE_SIZE
      
      @@
      @@
      - PAGE_CACHE_MASK
      + PAGE_MASK
      
      @@
      expression E;
      @@
      - PAGE_CACHE_ALIGN(E)
      + PAGE_ALIGN(E)
      
      @@
      expression E;
      @@
      - page_cache_get(E)
      + get_page(E)
      
      @@
      expression E;
      @@
      - page_cache_release(E)
      + put_page(E)
      Signed-off-by: 's avatarKirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Acked-by: 's avatarMichal Hocko <mhocko@suse.com>
      Signed-off-by: 's avatarLinus Torvalds <torvalds@linux-foundation.org>
      09cbfeaf
  16. 15 Jan, 2016 1 commit
    • Vladimir Davydov's avatar
      kmemcg: account certain kmem allocations to memcg · 5d097056
      Vladimir Davydov authored
      Mark those kmem allocations that are known to be easily triggered from
      userspace as __GFP_ACCOUNT/SLAB_ACCOUNT, which makes them accounted to
      memcg.  For the list, see below:
      
       - threadinfo
       - task_struct
       - task_delay_info
       - pid
       - cred
       - mm_struct
       - vm_area_struct and vm_region (nommu)
       - anon_vma and anon_vma_chain
       - signal_struct
       - sighand_struct
       - fs_struct
       - files_struct
       - fdtable and fdtable->full_fds_bits
       - dentry and external_name
       - inode for all filesystems. This is the most tedious part, because
         most filesystems overwrite the alloc_inode method.
      
      The list is far from complete, so feel free to add more objects.
      Nevertheless, it should be close to "account everything" approach and
      keep most workloads within bounds.  Malevolent users will be able to
      breach the limit, but this was possible even with the former "account
      everything" approach (simply because it did not account everything in
      fact).
      
      [akpm@linux-foundation.org: coding-style fixes]
      Signed-off-by: 's avatarVladimir Davydov <vdavydov@virtuozzo.com>
      Acked-by: 's avatarJohannes Weiner <hannes@cmpxchg.org>
      Acked-by: 's avatarMichal Hocko <mhocko@suse.com>
      Cc: Tejun Heo <tj@kernel.org>
      Cc: Greg Thelen <gthelen@google.com>
      Cc: Christoph Lameter <cl@linux.com>
      Cc: Pekka Enberg <penberg@kernel.org>
      Cc: David Rientjes <rientjes@google.com>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Signed-off-by: 's avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: 's avatarLinus Torvalds <torvalds@linux-foundation.org>
      5d097056
  17. 06 Jan, 2016 1 commit
  18. 30 Dec, 2015 1 commit
  19. 14 Dec, 2015 1 commit
  20. 09 Dec, 2015 2 commits
    • Al Viro's avatar
      replace ->follow_link() with new method that could stay in RCU mode · 6b255391
      Al Viro authored
      new method: ->get_link(); replacement of ->follow_link().  The differences
      are:
      	* inode and dentry are passed separately
      	* might be called both in RCU and non-RCU mode;
      the former is indicated by passing it a NULL dentry.
      	* when called that way it isn't allowed to block
      and should return ERR_PTR(-ECHILD) if it needs to be called
      in non-RCU mode.
      
      It's a flagday change - the old method is gone, all in-tree instances
      converted.  Conversion isn't hard; said that, so far very few instances
      do not immediately bail out when called in RCU mode.  That'll change
      in the next commits.
      Signed-off-by: 's avatarAl Viro <viro@zeniv.linux.org.uk>
      6b255391
    • Al Viro's avatar
      don't put symlink bodies in pagecache into highmem · 21fc61c7
      Al Viro authored
      kmap() in page_follow_link_light() needed to go - allowing to hold
      an arbitrary number of kmaps for long is a great way to deadlocking
      the system.
      
      new helper (inode_nohighmem(inode)) needs to be used for pagecache
      symlinks inodes; done for all in-tree cases.  page_follow_link_light()
      instrumented to yell about anything missed.
      Signed-off-by: 's avatarAl Viro <viro@zeniv.linux.org.uk>
      21fc61c7
  21. 07 Dec, 2015 1 commit
  22. 14 Nov, 2015 2 commits
  23. 23 Jun, 2015 1 commit
  24. 15 Apr, 2015 1 commit
  25. 27 Nov, 2014 2 commits
  26. 07 Aug, 2014 2 commits
  27. 04 Jun, 2014 1 commit
  28. 13 Mar, 2014 1 commit
    • Theodore Ts'o's avatar
      fs: push sync_filesystem() down to the file system's remount_fs() · 02b9984d
      Theodore Ts'o authored
      Previously, the no-op "mount -o mount /dev/xxx" operation when the
      file system is already mounted read-write causes an implied,
      unconditional syncfs().  This seems pretty stupid, and it's certainly
      documented or guaraunteed to do this, nor is it particularly useful,
      except in the case where the file system was mounted rw and is getting
      remounted read-only.
      
      However, it's possible that there might be some file systems that are
      actually depending on this behavior.  In most file systems, it's
      probably fine to only call sync_filesystem() when transitioning from
      read-write to read-only, and there are some file systems where this is
      not needed at all (for example, for a pseudo-filesystem or something
      like romfs).
      Signed-off-by: 's avatar"Theodore Ts'o" <tytso@mit.edu>
      Cc: linux-fsdevel@vger.kernel.org
      Cc: Christoph Hellwig <hch@infradead.org>
      Cc: Artem Bityutskiy <dedekind1@gmail.com>
      Cc: Adrian Hunter <adrian.hunter@intel.com>
      Cc: Evgeniy Dushistov <dushistov@mail.ru>
      Cc: Jan Kara <jack@suse.cz>
      Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
      Cc: Anders Larsen <al@alarsen.net>
      Cc: Phillip Lougher <phillip@squashfs.org.uk>
      Cc: Kees Cook <keescook@chromium.org>
      Cc: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz>
      Cc: Petr Vandrovec <petr@vandrovec.name>
      Cc: xfs@oss.sgi.com
      Cc: linux-btrfs@vger.kernel.org
      Cc: linux-cifs@vger.kernel.org
      Cc: samba-technical@lists.samba.org
      Cc: codalist@coda.cs.cmu.edu
      Cc: linux-ext4@vger.kernel.org
      Cc: linux-f2fs-devel@lists.sourceforge.net
      Cc: fuse-devel@lists.sourceforge.net
      Cc: cluster-devel@redhat.com
      Cc: linux-mtd@lists.infradead.org
      Cc: jfs-discussion@lists.sourceforge.net
      Cc: linux-nfs@vger.kernel.org
      Cc: linux-nilfs@vger.kernel.org
      Cc: linux-ntfs-dev@lists.sourceforge.net
      Cc: ocfs2-devel@oss.oracle.com
      Cc: reiserfs-devel@vger.kernel.org
      02b9984d
  29. 24 Nov, 2013 1 commit
  30. 20 Nov, 2013 5 commits
    • Phillip Lougher's avatar
      Squashfs: Check stream is not NULL in decompressor_multi.c · ed4f381e
      Phillip Lougher authored
      Fix static checker complaint that stream is not checked in
      squashfs_decompressor_destroy().
      Reported-by: 's avatarDan Carpenter <dan.carpenter@oracle.com>
      Signed-off-by: 's avatarPhillip Lougher <phillip@squashfs.org.uk>
      Reviewed-by: 's avatarMinchan Kim <minchan@kernel.org>
      ed4f381e
    • Phillip Lougher's avatar
      Squashfs: Directly decompress into the page cache for file data · 0d455c12
      Phillip Lougher authored
      This introduces an implementation of squashfs_readpage_block()
      that directly decompresses into the page cache.
      
      This uses the previously added page handler abstraction to push
      down the necessary kmap_atomic/kunmap_atomic operations on the
      page cache buffers into the decompressors.  This enables
      direct copying into the page cache without using the slow
      kmap/kunmap calls.
      
      The code detects when multiple threads are racing in
      squashfs_readpage() to decompress the same block, and avoids
      this regression by falling back to using an intermediate
      buffer.
      
      This patch enhances the performance of Squashfs significantly
      when multiple processes are accessing the filesystem simultaneously
      because it not only reduces memcopying, but it more importantly
      eliminates the lock contention on the intermediate buffer.
      
      Using single-thread decompression.
      
              dd if=file1 of=/dev/null bs=4096 &
              dd if=file2 of=/dev/null bs=4096 &
              dd if=file3 of=/dev/null bs=4096 &
              dd if=file4 of=/dev/null bs=4096
      
      Before:
      
      629145600 bytes (629 MB) copied, 45.8046 s, 13.7 MB/s
      
      After:
      
      629145600 bytes (629 MB) copied, 9.29414 s, 67.7 MB/s
      Signed-off-by: 's avatarPhillip Lougher <phillip@squashfs.org.uk>
      Reviewed-by: 's avatarMinchan Kim <minchan@kernel.org>
      0d455c12
    • Phillip Lougher's avatar
      Squashfs: Restructure squashfs_readpage() · 5f55dbc0
      Phillip Lougher authored
      Restructure squashfs_readpage() splitting it into separate
      functions for datablocks, fragments and sparse blocks.
      
      Move the memcpying (from squashfs cache entry) implementation of
      squashfs_readpage_block into file_cache.c
      
      This allows different implementations to be supported.
      Signed-off-by: 's avatarPhillip Lougher <phillip@squashfs.org.uk>
      Reviewed-by: 's avatarMinchan Kim <minchan@kernel.org>
      5f55dbc0
    • Phillip Lougher's avatar
      Squashfs: Generalise paging handling in the decompressors · 846b730e
      Phillip Lougher authored
      Further generalise the decompressors by adding a page handler
      abstraction.  This adds helpers to allow the decompressors
      to access and process the output buffers in an implementation
      independant manner.
      
      This allows different types of output buffer to be passed
      to the decompressors, with the implementation specific
      aspects handled at decompression time, but without the
      knowledge being held in the decompressor wrapper code.
      
      This will allow the decompressors to handle Squashfs
      cache buffers, and page cache pages.
      
      This patch adds the abstraction and an implementation for
      the caches.
      Signed-off-by: 's avatarPhillip Lougher <phillip@squashfs.org.uk>
      Reviewed-by: 's avatarMinchan Kim <minchan@kernel.org>
      846b730e
    • Phillip Lougher's avatar
      Squashfs: add multi-threaded decompression using percpu variable · d208383d
      Phillip Lougher authored
      Add a multi-threaded decompression implementation which uses
      percpu variables.
      
      Using percpu variables has advantages and disadvantages over
      implementations which do not use percpu variables.
      
      Advantages:
        * the nature of percpu variables ensures decompression is
          load-balanced across the multiple cores.
        * simplicity.
      
      Disadvantages: it limits decompression to one thread per core.
      Signed-off-by: 's avatarPhillip Lougher <phillip@squashfs.org.uk>
      d208383d