15 Mar, 2011

3 commits


17 Nov, 2010

1 commit


29 Oct, 2010

1 commit


15 Oct, 2010

1 commit

  • 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
     

01 Sep, 2010

1 commit


23 Jul, 2010

1 commit

  • All these files use the big kernel lock in a trivial
    way to serialize their private file operations,
    typically resulting from an earlier semi-automatic
    pushdown from VFS.

    None of these drivers appears to want to lock against
    other code, and they all use the BKL as the top-level
    lock in their file operations, meaning that there
    is no lock-order inversion problem.

    Consequently, we can remove the BKL completely,
    replacing it with a per-file mutex in every case.
    Using a scripted approach means we can avoid
    typos.

    file=$1
    name=$2
    if grep -q lock_kernel ${file} ; then
    if grep -q 'include.*linux.mutex.h' ${file} ; then
    sed -i '/include.*/d' ${file}
    else
    sed -i 's/include.*.*$/include /g' ${file}
    fi
    sed -i ${file} \
    -e "/^#include.*linux.mutex.h/,$ {
    1,/^\(static\|int\|long\)/ {
    /^\(static\|int\|long\)/istatic DEFINE_MUTEX(${name}_mutex);

    } }" \
    -e "s/\(un\)*lock_kernel\>[ ]*()/mutex_\1lock(\&${name}_mutex)/g" \
    -e '/[ ]*cycle_kernel_lock();/d'
    else
    sed -i -e '/include.*\/d' ${file} \
    -e '/cycle_kernel_lock()/d'
    fi

    Signed-off-by: Arnd Bergmann
    Signed-off-by: Greg Kroah-Hartman

    Arnd Bergmann
     

09 Jul, 2010

1 commit


19 Jun, 2010

1 commit


19 May, 2010

1 commit


12 May, 2010

4 commits


30 Mar, 2010

1 commit

  • …it slab.h inclusion from percpu.h

    percpu.h is included by sched.h and module.h and thus ends up being
    included when building most .c files. percpu.h includes slab.h which
    in turn includes gfp.h making everything defined by the two files
    universally available and complicating inclusion dependencies.

    percpu.h -> slab.h dependency is about to be removed. Prepare for
    this change by updating users of gfp and slab facilities include those
    headers directly instead of assuming availability. As this conversion
    needs to touch large number of source files, the following script is
    used as the basis of conversion.

    http://userweb.kernel.org/~tj/misc/slabh-sweep.py

    The script does the followings.

    * Scan files for gfp and slab usages and update includes such that
    only the necessary includes are there. ie. if only gfp is used,
    gfp.h, if slab is used, slab.h.

    * When the script inserts a new include, it looks at the include
    blocks and try to put the new include such that its order conforms
    to its surrounding. It's put in the include block which contains
    core kernel includes, in the same order that the rest are ordered -
    alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
    doesn't seem to be any matching order.

    * If the script can't find a place to put a new include (mostly
    because the file doesn't have fitting include block), it prints out
    an error message indicating which .h file needs to be added to the
    file.

    The conversion was done in the following steps.

    1. The initial automatic conversion of all .c files updated slightly
    over 4000 files, deleting around 700 includes and adding ~480 gfp.h
    and ~3000 slab.h inclusions. The script emitted errors for ~400
    files.

    2. Each error was manually checked. Some didn't need the inclusion,
    some needed manual addition while adding it to implementation .h or
    embedding .c file was more appropriate for others. This step added
    inclusions to around 150 files.

    3. The script was run again and the output was compared to the edits
    from #2 to make sure no file was left behind.

    4. Several build tests were done and a couple of problems were fixed.
    e.g. lib/decompress_*.c used malloc/free() wrappers around slab
    APIs requiring slab.h to be added manually.

    5. The script was run on all .h files but without automatically
    editing them as sprinkling gfp.h and slab.h inclusions around .h
    files could easily lead to inclusion dependency hell. Most gfp.h
    inclusion directives were ignored as stuff from gfp.h was usually
    wildly available and often used in preprocessor macros. Each
    slab.h inclusion directive was examined and added manually as
    necessary.

    6. percpu.h was updated not to include slab.h.

    7. Build test were done on the following configurations and failures
    were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
    distributed build env didn't work with gcov compiles) and a few
    more options had to be turned off depending on archs to make things
    build (like ipr on powerpc/64 which failed due to missing writeq).

    * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
    * powerpc and powerpc64 SMP allmodconfig
    * sparc and sparc64 SMP allmodconfig
    * ia64 SMP allmodconfig
    * s390 SMP allmodconfig
    * alpha SMP allmodconfig
    * um on x86_64 SMP allmodconfig

    8. percpu.h modifications were reverted so that it could be applied as
    a separate patch and serve as bisection point.

    Given the fact that I had only a couple of failures from tests on step
    6, I'm fairly confident about the coverage of this conversion patch.
    If there is a breakage, it's likely to be something in one of the arch
    headers which should be easily discoverable easily on most builds of
    the specific arch.

    Signed-off-by: Tejun Heo <tj@kernel.org>
    Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
    Cc: Ingo Molnar <mingo@redhat.com>
    Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

    Tejun Heo
     

04 Mar, 2010

2 commits

  • This patch does following improvements:

    1. Follow kernel style for comments
    2. Reorganize code for readability improvement
    3. Use PCI helper macros
    4. Use __devinit, __devexit, __devexit_p at necessary places
    5. Mark functions and data as static when it is not exported

    Signed-off-by: Ameya Palande
    Cc: Naren Sankar
    Cc: Jarod Wilson
    Cc: Scott Davilla
    Cc: Manu Abraham
    Signed-off-by: Greg Kroah-Hartman

    Ameya Palande
     
  • This patch supersedes the earlier ones sent by Manu Abraham to add
    the Broadcom Crystal HD driver to the staging tree, per discussion
    with him about it. I've been working with Broadcom's Naren Sankar
    on this driver for a number of months, and had already talked Naren
    about submitting this on Broadcom's behalf, didn't expect anyone
    else to jump on submitting it as quickly as Manu did. ;)

    This version is a one-shot deal, incorporating the original driver,
    Manu's coding style clean-ups, udev device creation support from
    Edgar 'gimli' Hucek, and a number of other small tweaks from myself
    and Scott Davilla, the other individual who has been working closely
    on this code with Naren and I.

    I've tested this iteration of the code lightly on a mini pci-e board
    in a ThinkPad T61p running x86_64 Fedora 12, with the expected results,
    and will test further on other systems with other variants of the card
    (I have three varieties of this device currently in hand). Scott has
    also tested on assorted primarily i686 varieties of Ubuntu, and Naren
    has tested with both Fedora and Ubuntu, iirc.

    Note: only the 70012 is currently supported by this driver, 70015
    support will follow later. Also note that Blu-Ray support isn't
    enabled (at the firmware level), due to misc fun related to the
    BD encryption scheme, DRM, etc. :\

    I *do* have a git tree containing the driver, lib, gst plugin and
    firmware that I'm working from at the moment[*], as there are inter-
    dependencies between the driver and lib, and the driver can be used
    with kernels going a ways back (I've only tested back to 2.6.18 as
    it exists in Red Hat Enterprise Linux 5). I'm exporting from there,
    into a linux-next tree, then generating patches from there. The goal
    is to feed everything upstream as quickly as possible, but there are
    users who want this code for earlier kernels too...

    The firmware will be submitted for inclusion in dwmw2's linux-firmware
    tree once there is a suitable redistribution-no-modification type of
    license on it (I believe Naren is working with Broadcom legal to get
    that in place).

    Changelog from initial Broadcom release to here:

    commit d20475d444610c5683d09e63f707f5bb22359062
    Author: Jarod Wilson
    Date: Mon Jan 4 13:55:16 2010 -0500

    include: lib doesn't build w/o the removed stdint include

    So add it back...

    Signed-off-by: Jarod Wilson

    commit c181070a330530b792d2b80e3ec6ab12a5a57394
    Author: Scott Davilla
    Date: Mon Jan 4 13:38:37 2010 -0500

    include: don't define VOID if its already defined

    Signed-off-by: Scott Davilla
    Signed-off-by: Jarod Wilson

    commit 33d8a2b691e81212e398f53770578d79650bf0bc
    Author: Jarod Wilson
    Date: Mon Jan 4 13:12:10 2010 -0500

    driver: create crystalhd device using udev

    Based on:
    http://sourceforge.net/apps/trac/archvdr/browser/trunk/archvdr/crystalhd/use_udev.patch

    Signed-off-by: Edgar ( gimli ) Hucek

    Formatting tweaks, error-handling path fixups and any bugs added by Jarod.

    Signed-off-by: Jarod Wilson

    commit c44c64dea5537814796fcbe2d9db0209383c78b9
    Author: Manu Abraham
    Date: Mon Jan 4 10:32:47 2010 -0500

    crystalhd: coding style cleanups

    Signed-off-by: Manu Abraham
    Signed-off-by: Jarod Wilson

    commit cffa6da7467ff697a656d1dfff54bb0513a053dc
    Author: Jarod Wilson
    Date: Mon Jan 4 10:17:27 2010 -0500

    crystalhd: run dos2unix over everything, this is linux source...

    Signed-off-by: Jarod Wilson

    commit 7fa38a282db7af5a5746055f7c6cef8a9b8ee138
    Author: Jarod Wilson
    Date: Mon Jan 4 10:02:33 2010 -0500

    crystalhd: initial import of released Broadcom code

    Straight import of:
    http://www.broadcom.com/docs/support/crystalhd/crystalhd_linux_20091229.zip

    Unfortunately, we're unable to publicly publish all the history that got
    us from the initial internal code to what was released here, but such is
    life, we can just be happy we've got this open-sourced now. :)

    Signed-off-by: Jarod Wilson

    Signed-off-by: Naren Sankar
    Signed-off-by: Scott Davilla
    Signed-off-by: Manu Abraham
    Signed-off-by: Jarod Wilson
    Signed-off-by: Greg Kroah-Hartman

    Jarod Wilson