08 May, 2007

1 commit

  • Ensure pages are uptodate after returning from read_cache_page, which allows
    us to cut out most of the filesystem-internal PageUptodate calls.

    I didn't have a great look down the call chains, but this appears to fixes 7
    possible use-before uptodate in hfs, 2 in hfsplus, 1 in jfs, a few in
    ecryptfs, 1 in jffs2, and a possible cleared data overwritten with readpage in
    block2mtd. All depending on whether the filler is async and/or can return
    with a !uptodate page.

    Signed-off-by: Nick Piggin
    Cc: Hugh Dickins
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Nick Piggin
     

13 Feb, 2007

2 commits

  • This patch is inspired by Arjan's "Patch series to mark struct
    file_operations and struct inode_operations const".

    Compile tested with gcc & sparse.

    Signed-off-by: Josef 'Jeff' Sipek
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Josef 'Jeff' Sipek
     
  • Many struct inode_operations in the kernel can be "const". Marking them const
    moves these to the .rodata section, which avoids false sharing with potential
    dirty data. In addition it'll catch accidental writes at compile time to
    these shared resources.

    Signed-off-by: Arjan van de Ven
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Arjan van de Ven
     

09 Dec, 2006

1 commit


08 Dec, 2006

1 commit

  • Steve Grubb's fzfuzzer tool (http://people.redhat.com/sgrubb/files/
    fsfuzzer-0.6.tar.gz) generates corrupt Cramfs filesystems which cause
    Cramfs to kernel oops in cramfs_uncompress_block(). The cause of the oops
    is an unchecked corrupted block length field read by cramfs_readpage().

    This patch adds a sanity check to cramfs_readpage() which checks that the
    block length field is sensible. The (PAGE_CACHE_SIZE << 1) size check is
    intentional, even though the uncompressed data is not going to be larger
    than PAGE_CACHE_SIZE, gzip sometimes generates compressed data larger than
    the original source data. Mkcramfs checks that the compressed size is
    always less than or equal to PAGE_CACHE_SIZE << 1. Of course Cramfs could
    use the original uncompressed data in this case, but it doesn't.

    Signed-off-by: Phillip Lougher
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Phillip Lougher
     

30 Sep, 2006

2 commits


27 Sep, 2006

2 commits


29 Jun, 2006

1 commit


23 Jun, 2006

3 commits

  • Add read_mapping_page() which is used for callers that pass
    mapping->a_ops->readpage as the filler for read_cache_page. This removes
    some duplication from filesystem code.

    Signed-off-by: Pekka Enberg
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Pekka Enberg
     
  • Give the statfs superblock operation a dentry pointer rather than a superblock
    pointer.

    This complements the get_sb() patch. That reduced the significance of
    sb->s_root, allowing NFS to place a fake root there. However, NFS does
    require a dentry to use as a target for the statfs operation. This permits
    the root in the vfsmount to be used instead.

    linux/mount.h has been added where necessary to make allyesconfig build
    successfully.

    Interest has also been expressed for use with the FUSE and XFS filesystems.

    Signed-off-by: David Howells
    Acked-by: Al Viro
    Cc: Nathan Scott
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    David Howells
     
  • Extend the get_sb() filesystem operation to take an extra argument that
    permits the VFS to pass in the target vfsmount that defines the mountpoint.

    The filesystem is then required to manually set the superblock and root dentry
    pointers. For most filesystems, this should be done with simple_set_mnt()
    which will set the superblock pointer and then set the root dentry to the
    superblock's s_root (as per the old default behaviour).

    The get_sb() op now returns an integer as there's now no need to return the
    superblock pointer.

    This patch permits a superblock to be implicitly shared amongst several mount
    points, such as can be done with NFS to avoid potential inode aliasing. In
    such a case, simple_set_mnt() would not be called, and instead the mnt_root
    and mnt_sb would be set directly.

    The patch also makes the following changes:

    (*) the get_sb_*() convenience functions in the core kernel now take a vfsmount
    pointer argument and return an integer, so most filesystems have to change
    very little.

    (*) If one of the convenience function is not used, then get_sb() should
    normally call simple_set_mnt() to instantiate the vfsmount. This will
    always return 0, and so can be tail-called from get_sb().

    (*) generic_shutdown_super() now calls shrink_dcache_sb() to clean up the
    dcache upon superblock destruction rather than shrink_dcache_anon().

    This is required because the superblock may now have multiple trees that
    aren't actually bound to s_root, but that still need to be cleaned up. The
    currently called functions assume that the whole tree is rooted at s_root,
    and that anonymous dentries are not the roots of trees which results in
    dentries being left unculled.

    However, with the way NFS superblock sharing are currently set to be
    implemented, these assumptions are violated: the root of the filesystem is
    simply a dummy dentry and inode (the real inode for '/' may well be
    inaccessible), and all the vfsmounts are rooted on anonymous[*] dentries
    with child trees.

    [*] Anonymous until discovered from another tree.

    (*) The documentation has been adjusted, including the additional bit of
    changing ext2_* into foo_* in the documentation.

    [akpm@osdl.org: convert ipath_fs, do other stuff]
    Signed-off-by: David Howells
    Acked-by: Al Viro
    Cc: Nathan Scott
    Cc: Roland Dreier
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    David Howells
     

29 Mar, 2006

1 commit

  • This is a conversion to make the various file_operations structs in fs/
    const. Basically a regexp job, with a few manual fixups

    The goal is both to increase correctness (harder to accidentally write to
    shared datastructures) and reducing the false sharing of cachelines with
    things that get dirty in .data (while .rodata is nicely read only and thus
    cache clean)

    Signed-off-by: Arjan van de Ven
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Arjan van de Ven
     

27 Mar, 2006

1 commit

  • Semaphore to mutex conversion.

    The conversion was generated via scripts, and the result was validated
    automatically via a script as well.

    Signed-off-by: Ingo Molnar
    Cc: Eric Van Hensbergen
    Cc: Robert Love
    Cc: Thomas Gleixner
    Cc: David Woodhouse
    Cc: Neil Brown
    Cc: Trond Myklebust
    Cc: Dave Kleikamp
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ingo Molnar
     

07 Mar, 2006

1 commit

  • Fix handling of cramfs images created by util-linux containing empty
    regular files. Images created by cramfstools 1.x were ok.

    Fill out inode contents in cramfs_iget5_set() instead of get_cramfs_inode()
    to prevent issues if cramfs_iget5_test() is called with I_LOCK|I_NEW still
    set.

    Signed-off-by: Dave Johnson
    Cc: Olaf Hering
    Cc: Chris Mason
    Cc: Andreas Gruenbacher
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Dave Johnson