04 Jan, 2012

1 commit

  • These new callbacks notify the dlm user about lock recovery.
    GFS2, and possibly others, need to be aware of when the dlm
    will be doing lock recovery for a failed lockspace member.

    In the past, this coordination has been done between dlm and
    file system daemons in userspace, which then direct their
    kernel counterparts. These callbacks allow the same
    coordination directly, and more simply.

    Signed-off-by: David Teigland

    David Teigland
     

19 Nov, 2010

1 commit

  • If ocfs2_live_connection_list is empty, ocfs2_connection_find() will return
    a pointer to the LIST_HEAD, cast as a ocfs2_live_connection. This can cause
    an oops when ocfs2_control_send_down() dereferences c->oc_conn:

    Call Trace:
    [] ocfs2_control_message+0x28c/0x2b0 [ocfs2_stack_user]
    [] ocfs2_control_write+0x35/0xb0 [ocfs2_stack_user]
    [] vfs_write+0xb8/0x1a0
    [] ? do_page_fault+0x153/0x3b0
    [] sys_write+0x51/0x80
    [] system_call_fastpath+0x16/0x1b

    Fix by explicitly returning NULL if no match is found.

    Signed-off-by: dann frazier
    Signed-off-by: Joel Becker

    dann frazier
     

23 Oct, 2010

1 commit

  • * '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

  • 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

  • The BKL in ocfs2/dlmfs is used in put_super, fill_super and remount_fs
    that are all three protected by the superblocks s_umount rw_semaphore.

    The use in ocfs2_control_open is evidently unrelated and the function
    is protected by ocfs2_control_lock.

    Therefore it is safe to remove the BKL entirely.

    Signed-off-by: Arnd Bergmann
    Cc: Mark Fasheh
    Cc: Joel Becker

    Arnd Bergmann
     

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
     

27 Feb, 2010

4 commits

  • With the full ocfs2_locking_protocol hanging off of the
    ocfs2_cluster_connection, ast wrappers can get the ast/bast pointers
    there. They don't need to get them from their plugin structure.

    The user plugin still needs the maximum locking protocol version,
    though. This changes the plugin structure so that it only holds the max
    version, not the entire ocfs2_locking_protocol pointer.

    Signed-off-by: Joel Becker

    Joel Becker
     
  • With the ocfs2_cluster_connection hanging off of the ocfs2_dlm_lksb, we
    have access to it in the ast and bast wrapper functions. Attach the
    ocfs2_locking_protocol to the conn.

    Now, instead of refering to a static variable for ast/bast pointers, the
    wrappers can look at the connection. This means different connections
    can have different ast/bast pointers, and it reduces the need for the
    static pointer.

    Signed-off-by: Joel Becker

    Joel Becker
     
  • We're going to want it in the ast functions, so we convert union
    ocfs2_dlm_lksb to struct ocfs2_dlm_lksb and let it carry the connection.

    Signed-off-by: Joel Becker

    Joel Becker
     
  • The stackglue ast and bast functions tried to maintain the fiction that
    their arguments were void pointers. In reality, stack_user.c had to
    know that the argument was an ocfs2_lock_res in order to get the status
    off of the lksb. That's ugly.

    This changes stackglue to always pass the lksb as the argument to ast
    and bast functions. The caller can always use container_of() to get the
    ocfs2_lock_res or user_dlm_lock_res. The net effect to the caller is
    zero. They still get back the lockres in their ast. stackglue gets
    cleaner, and now can use the lksb itself.

    Signed-off-by: Joel Becker

    Joel Becker
     

18 Dec, 2009

1 commit


23 Jun, 2009

1 commit

  • The Lock Value Block (LVB) of a DLM lock can be lost when nodes die and
    the DLM cannot reconstruct its state. Clients of the DLM need to know
    this.

    ocfs2's internal DLM, o2dlm, explicitly zeroes out the LVB when it loses
    track of the state. This is not a standard behavior, but ocfs2 has
    always relied on it. Thus, an o2dlm LVB is always "valid".

    ocfs2 now supports both o2dlm and fs/dlm via the stack glue. When
    fs/dlm loses track of an LVBs state, it sets a flag
    (DLM_SBF_VALNOTVALID) on the Lock Status Block (LKSB). The contents of
    the LVB may be garbage or merely stale.

    ocfs2 doesn't want to try to guess at the validity of the stale LVB.
    Instead, it should be checking the VALNOTVALID flag. As this is the
    'standard' way of treating LVBs, we will promote this behavior.

    We add a stack glue API ocfs2_dlm_lvb_valid(). It returns non-zero when
    the LVB is valid. o2dlm will always return valid, while fs/dlm will
    check VALNOTVALID.

    Signed-off-by: Joel Becker
    Acked-by: Mark Fasheh

    Joel Becker
     

02 Dec, 2008

1 commit


14 Oct, 2008

1 commit

  • This is actually pretty easy since fs/dlm already handles the bulk of the
    work. The Ocfs2 userspace cluster stack module already uses fs/dlm as the
    underlying lock manager, so I only had to add the right calls.

    Cluster-aware POSIX locks ("plocks") can be turned off by the same means at
    UNIX locks - mount with 'noflocks', or create a local-only Ocfs2 volume.
    Internally, the file system uses two sets of file_operations, depending on
    whether cluster aware plocks is required. This turns out to be easier than
    implementing local-only versions of ->lock.

    Signed-off-by: Mark Fasheh

    Mark Fasheh
     

18 Jul, 2008

1 commit

  • * 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2:
    [PATCH] ocfs2: fix oops in mmap_truncate testing
    configfs: call drop_link() to cleanup after create_link() failure
    configfs: Allow ->make_item() and ->make_group() to return detailed errors.
    configfs: Fix failing mkdir() making racing rmdir() fail
    configfs: Fix deadlock with racing rmdir() and rename()
    configfs: Make configfs_new_dirent() return error code instead of NULL
    configfs: Protect configfs_dirent s_links list mutations
    configfs: Introduce configfs_dirent_lock
    ocfs2: Don't snprintf() without a format.
    ocfs2: Fix CONFIG_OCFS2_DEBUG_FS #ifdefs
    ocfs2/net: Silence build warnings on sparc64
    ocfs2: Handle error during journal load
    ocfs2: Silence an error message in ocfs2_file_aio_read()
    ocfs2: use simple_read_from_buffer()
    ocfs2: fix printk format warnings with OCFS2_FS_STATS=n
    [PATCH 2/2] ocfs2: Instrument fs cluster locks
    [PATCH 1/2] ocfs2: Add CONFIG_OCFS2_FS_STATS config option

    Linus Torvalds
     

15 Jul, 2008

2 commits


03 Jul, 2008

1 commit


17 Jun, 2008

1 commit


31 May, 2008

1 commit


01 May, 2008

1 commit


18 Apr, 2008

7 commits