Eric Lee / linux-smarc-t335x-v3.2

26 Jul, 2011

1 commit

22 Jul, 2011

1 commit

  • cc6d34971   Squashfs: Make ZLIB compression support optional ... Browse Code »

    Squashfs now supports XZ and LZO compression in addition to ZLIB.
    As such it no longer makes sense to always include ZLIB support.
    In particular embedded systems may only use LZO or XZ compression, and
    the ability to exclude ZLIB support will reduce kernel size.

    Signed-off-by: Phillip Lougher

    Phillip Lougher
     

20 Jul, 2011

2 commits

30 May, 2011

1 commit

29 May, 2011

1 commit

27 May, 2011

1 commit

  • bc9bc72e2   Merge git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-linus ... Browse Code »

    * git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-linus:
    Squashfs: update email address
    Squashfs: add extra sanity checks at mount time
    Squashfs: add sanity checks to fragment reading at mount time
    Squashfs: add sanity checks to lookup table reading at mount time
    Squashfs: add sanity checks to id reading at mount time
    Squashfs: add sanity checks to xattr reading at mount time
    Squashfs: reverse order of filesystem table reading
    Squashfs: move table allocation into squashfs_read_table()

    Linus Torvalds
     

26 May, 2011

8 commits

10 May, 2011

1 commit

31 Mar, 2011

1 commit

23 Mar, 2011

1 commit

16 Mar, 2011

1 commit

  • 44cff8a9e   Squashfs: handle corruption of directory structure ... Browse Code »

    Handle the rare case where a directory metadata block is uncompressed and
    corrupted, leading to a kernel oops in directory scanning (memcpy).
    Normally corruption is detected at the decompression stage and dealt with
    then, however, this will not happen if:

    - metadata isn't compressed (users can optionally request no metadata
    compression), or
    - the compressed metadata block was larger than the original, in which
    case the uncompressed version was used, or
    - the data was corrupt after decompression

    This patch fixes this by adding some sanity checks against known maximum
    values.

    Signed-off-by: Phillip Lougher

    Phillip Lougher
     

01 Mar, 2011

5 commits

26 Jan, 2011

1 commit

  • 3689456b4   squashfs: fix use of uninitialised variable in zlib & xz decompressors ... Browse Code »

    Fix potential use of uninitialised variable caused by recent
    decompressor code optimisations.

    In zlib_uncompress (zlib_wrapper.c) we have

    int zlib_err, zlib_init = 0;
    ...
    do {
    ...
    if (avail == 0) {
    offset = 0;
    put_bh(bh[k++]);
    continue;
    }
    ...
    zlib_err = zlib_inflate(stream, Z_SYNC_FLUSH);
    ...
    } while (zlib_err == Z_OK);

    If continue is executed (avail == 0) then the while condition will be
    evaluated testing zlib_err, which is uninitialised first time around the
    loop.

    Fix this by getting rid of the 'if (avail == 0)' condition test, this
    edge condition should not be being handled in the decompressor code, and
    instead handle it generically in the caller code.

    Similarly for xz_wrapper.c.

    Incidentally, on most architectures (bar Mips and Parisc), no
    uninitialised variable warning is generated by gcc, this is because the
    while condition test on continue is optimised out and not performed
    (when executing continue zlib_err has not been changed since entering
    the loop, and logically if the while condition was true previously, then
    it's still true).

    Signed-off-by: Phillip Lougher
    Reported-by: Jesper Juhl
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Phillip Lougher
     

14 Jan, 2011

7 commits

07 Jan, 2011

1 commit

  • fa0d7e3de   fs: icache RCU free inodes ... Browse Code »

    RCU free the struct inode. This will allow:

    - Subsequent store-free path walking patch. The inode must be consulted for
    permissions when walking, so an RCU inode reference is a must.
    - sb_inode_list_lock to be moved inside i_lock because sb list walkers who want
    to take i_lock no longer need to take sb_inode_list_lock to walk the list in
    the first place. This will simplify and optimize locking.
    - Could remove some nested trylock loops in dcache code
    - Could potentially simplify things a bit in VM land. Do not need to take the
    page lock to follow page->mapping.

    The downsides of this is the performance cost of using RCU. In a simple
    creat/unlink microbenchmark, performance drops by about 10% due to inability to
    reuse cache-hot slab objects. As iterations increase and RCU freeing starts
    kicking over, this increases to about 20%.

    In cases where inode lifetimes are longer (ie. many inodes may be allocated
    during the average life span of a single inode), a lot of this cache reuse is
    not applicable, so the regression caused by this patch is smaller.

    The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU,
    however this adds some complexity to list walking and store-free path walking,
    so I prefer to implement this at a later date, if it is shown to be a win in
    real situations. I haven't found a regression in any non-micro benchmark so I
    doubt it will be a problem.

    Signed-off-by: Nick Piggin

    Nick Piggin
     

29 Oct, 2010

4 commits

23 Oct, 2010

1 commit

  • 092e0e7e5   Merge branch 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl ... Browse Code »

    * 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl:
    vfs: make no_llseek the default
    vfs: don't use BKL in default_llseek
    llseek: automatically add .llseek fop
    libfs: use generic_file_llseek for simple_attr
    mac80211: disallow seeks in minstrel debug code
    lirc: make chardev nonseekable
    viotape: use noop_llseek
    raw: use explicit llseek file operations
    ibmasmfs: use generic_file_llseek
    spufs: use llseek in all file operations
    arm/omap: use generic_file_llseek in iommu_debug
    lkdtm: use generic_file_llseek in debugfs
    net/wireless: use generic_file_llseek in debugfs
    drm: use noop_llseek

    Linus Torvalds
     

15 Oct, 2010

1 commit

  • 6038f373a   llseek: automatically add .llseek fop ... Browse Code »

    All file_operations should get a .llseek operation so we can make
    nonseekable_open the default for future file operations without a
    .llseek pointer.

    The three cases that we can automatically detect are no_llseek, seq_lseek
    and default_llseek. For cases where we can we can automatically prove that
    the file offset is always ignored, we use noop_llseek, which maintains
    the current behavior of not returning an error from a seek.

    New drivers should normally not use noop_llseek but instead use no_llseek
    and call nonseekable_open at open time. Existing drivers can be converted
    to do the same when the maintainer knows for certain that no user code
    relies on calling seek on the device file.

    The generated code is often incorrectly indented and right now contains
    comments that clarify for each added line why a specific variant was
    chosen. In the version that gets submitted upstream, the comments will
    be gone and I will manually fix the indentation, because there does not
    seem to be a way to do that using coccinelle.

    Some amount of new code is currently sitting in linux-next that should get
    the same modifications, which I will do at the end of the merge window.

    Many thanks to Julia Lawall for helping me learn to write a semantic
    patch that does all this.

    ===== begin semantic patch =====
    // This adds an llseek= method to all file operations,
    // as a preparation for making no_llseek the default.
    //
    // The rules are
    // - use no_llseek explicitly if we do nonseekable_open
    // - use seq_lseek for sequential files
    // - use default_llseek if we know we access f_pos
    // - use noop_llseek if we know we don't access f_pos,
    // but we still want to allow users to call lseek
    //
    @ open1 exists @
    identifier nested_open;
    @@
    nested_open(...)
    {

    }

    @ open exists@
    identifier open_f;
    identifier i, f;
    identifier open1.nested_open;
    @@
    int open_f(struct inode *i, struct file *f)
    {

    }

    @ read disable optional_qualifier exists @
    identifier read_f;
    identifier f, p, s, off;
    type ssize_t, size_t, loff_t;
    expression E;
    identifier func;
    @@
    ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
    {

    }

    @ read_no_fpos disable optional_qualifier exists @
    identifier read_f;
    identifier f, p, s, off;
    type ssize_t, size_t, loff_t;
    @@
    ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
    {
    ... when != off
    }

    @ write @
    identifier write_f;
    identifier f, p, s, off;
    type ssize_t, size_t, loff_t;
    expression E;
    identifier func;
    @@
    ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
    {

    }

    @ write_no_fpos @
    identifier write_f;
    identifier f, p, s, off;
    type ssize_t, size_t, loff_t;
    @@
    ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
    {
    ... when != off
    }

    @ fops0 @
    identifier fops;
    @@
    struct file_operations fops = {
    ...
    };

    @ has_llseek depends on fops0 @
    identifier fops0.fops;
    identifier llseek_f;
    @@
    struct file_operations fops = {
    ...
    .llseek = llseek_f,
    ...
    };

    @ has_read depends on fops0 @
    identifier fops0.fops;
    identifier read_f;
    @@
    struct file_operations fops = {
    ...
    .read = read_f,
    ...
    };

    @ has_write depends on fops0 @
    identifier fops0.fops;
    identifier write_f;
    @@
    struct file_operations fops = {
    ...
    .write = write_f,
    ...
    };

    @ has_open depends on fops0 @
    identifier fops0.fops;
    identifier open_f;
    @@
    struct file_operations fops = {
    ...
    .open = open_f,
    ...
    };

    // use no_llseek if we call nonseekable_open
    ////////////////////////////////////////////
    @ nonseekable1 depends on !has_llseek && has_open @
    identifier fops0.fops;
    identifier nso ~= "nonseekable_open";
    @@
    struct file_operations fops = {
    ... .open = nso, ...
    +.llseek = no_llseek, /* nonseekable */
    };

    @ nonseekable2 depends on !has_llseek @
    identifier fops0.fops;
    identifier open.open_f;
    @@
    struct file_operations fops = {
    ... .open = open_f, ...
    +.llseek = no_llseek, /* open uses nonseekable */
    };

    // use seq_lseek for sequential files
    /////////////////////////////////////
    @ seq depends on !has_llseek @
    identifier fops0.fops;
    identifier sr ~= "seq_read";
    @@
    struct file_operations fops = {
    ... .read = sr, ...
    +.llseek = seq_lseek, /* we have seq_read */
    };

    // use default_llseek if there is a readdir
    ///////////////////////////////////////////
    @ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    identifier readdir_e;
    @@
    // any other fop is used that changes pos
    struct file_operations fops = {
    ... .readdir = readdir_e, ...
    +.llseek = default_llseek, /* readdir is present */
    };

    // use default_llseek if at least one of read/write touches f_pos
    /////////////////////////////////////////////////////////////////
    @ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    identifier read.read_f;
    @@
    // read fops use offset
    struct file_operations fops = {
    ... .read = read_f, ...
    +.llseek = default_llseek, /* read accesses f_pos */
    };

    @ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    identifier write.write_f;
    @@
    // write fops use offset
    struct file_operations fops = {
    ... .write = write_f, ...
    + .llseek = default_llseek, /* write accesses f_pos */
    };

    // Use noop_llseek if neither read nor write accesses f_pos
    ///////////////////////////////////////////////////////////

    @ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    identifier read_no_fpos.read_f;
    identifier write_no_fpos.write_f;
    @@
    // write fops use offset
    struct file_operations fops = {
    ...
    .write = write_f,
    .read = read_f,
    ...
    +.llseek = noop_llseek, /* read and write both use no f_pos */
    };

    @ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    identifier write_no_fpos.write_f;
    @@
    struct file_operations fops = {
    ... .write = write_f, ...
    +.llseek = noop_llseek, /* write uses no f_pos */
    };

    @ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    identifier read_no_fpos.read_f;
    @@
    struct file_operations fops = {
    ... .read = read_f, ...
    +.llseek = noop_llseek, /* read uses no f_pos */
    };

    @ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    @@
    struct file_operations fops = {
    ...
    +.llseek = noop_llseek, /* no read or write fn */
    };
    ===== End semantic patch =====

    Signed-off-by: Arnd Bergmann
    Cc: Julia Lawall
    Cc: Christoph Hellwig

    Arnd Bergmann
     

05 Oct, 2010

1 commit

  • 3dbc4b32d   BKL: Remove BKL from squashfs ... Browse Code »

    The BKL is only used in put_super and fill_super, which are both protected
    by the superblocks s_umount rw_semaphore. Therefore it is safe to remove
    the BKL entirely.

    Signed-off-by: Arnd Bergmann
    Cc: Phillip Lougher

    Arnd Bergmann