Add sysfs_dirent->s_parent.  With this patch, each sd points to and
holds a reference to its parent.  This allows walking sysfs tree
without referencing sd->s_dentry which can go away anytime if the user
doesn't control when it's deleted.

sd->s_parent is initialized and parent is referenced in
sysfs_attach_dirent().  Reference to parent is released when the sd is
released, so as long as reference to a sd is held, s_parent can be
followed.

dentry walk in sysfs_readdir() is convereted to s_parent walk.

This will be used to reimplement symlink such that it uses only
sysfs_dirent tree.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Currently there are four functions to create sysfs_dirent -
__sysfs_new_dirent(), sysfs_new_dirent(), __sysfs_make_dirent() and
sysfs_make_dirent().  Other than sysfs_make_dirent(), no function has
two users if calls to implement other functions are excluded.

This patch consolidates sysfs_dirent creation functions into the
following two.

* sysfs_new_dirent() : allocate and initialize
* sysfs_attach_dirent() : attach to sysfs_dirent hierarchy and/or
			  associate with dentry

This simplifies interface and gives callers more flexibility.  This is
in preparation of object reference simplification.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Error handling in sysfs_rename_dir() was broken.

* When lookup_one_len() fails, 0 is returned.

* If parent inode check fails, returns with inode mutex and rename
  rwsem held.

This patch fixes the above bugs and flattens error handling such that
it's more readable and easier to modify.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Flatten cleanup paths in sysfs_add_link() and create_dir() to improve
readability and ease further changes to these functions.  This is in
preparation of object reference simplification.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Error handling in fs/sysfs/bin.c:write() was wrong because size_t
count is used to receive return value from flush_write() which is
negative on failure.

This patch updates write() such that int variable is used instead.
read() is updated the same way for consistency.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Make sysfs_put() ignore NULL sd instead of oopsing.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

sysfs used simple incrementing allocator which is not guaranteed to be
unique.  This patch makes sysfs use ida to give each sd a unique and
packed inode number.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

There is no reason this function should be inlined and soon to follow
sysfs object reference simplification will make it heavier.  Move it
to dir.c.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Implement debugfs_rename() to allow renaming files/directories in debugfs.
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Many places in kernel use seq_file API to iterate over a regular list_head.
The code for such iteration is identical in all the places, so it's worth
introducing a common helpers.

This makes code about 300 lines smaller:

The first version of this patch made the helper functions static inline
in the seq_file.h header. This patch moves them to the fs/seq_file.c as
Andrew proposed. The vmlinux .text section sizes are as follows:

2.6.22-rc1-mm1:              0x001794d5
with the previous version:   0x00179505
with this patch:             0x00179135

The config file used was make allnoconfig with the "y" inclusion of all
the possible options to make the files modified by the patch compile plus
drivers I have on the test node.

This patch:

Many places in kernel use seq_file API to iterate over a regular list_head.
The code for such iteration is identical in all the places, so it's worth
introducing a common helpers.
Signed-off-by: NPavel Emelianov <xemul@openvz.org>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

On Tue, 2007-07-10 at 10:06 +0100, Christoph Hellwig wrote:
> > -#define GFS2_LARGE_FH_SIZE 10
> > -
> > -struct gfs2_fh_obj {
> > -   struct gfs2_inum_host this;
> > -   u32 imode;
> > -};
> > +#define GFS2_LARGE_FH_SIZE 8
>
> Because gfs2_decode_fh only accepts file handles with GFS2_LARGE_FH_SIZE
> or GFS2_LARGE_FH_SIZE you don't accept filehandles sent out by and older
> gfs version anymore.  Stale filehandles because of a new kernel version
> are a big no-no, so please add back code to handle the old filehandles
> on the decode side.
>

This should fix that problem I think since its only relating to end of
the fh we can just ignore that field in order to accept the older
format.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Wendy Cheng <wcheng@redhat.com>

CDL formated DASDs are now detected correctly even if no VOL1 label is
on the disk. This prevents possible loss of data.
Signed-off-by: NStefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

As per Andrew Mortons request, here's a set of documentation for
the generic pipe_buf_operations hooks, the pipe, and pipe_buffer
structures.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

The name 'pin' was badly chosen, it doesn't pin a pipe buffer
in the most commonly used sense in the kernel. So change the
name to 'confirm', after debating this issue with Hugh
Dickins a bit.

A good return from ->confirm() means that the buffer is really
there, and that the contents are good.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

There are now zero users of .sendfile() in the kernel, so kill
it from the file_operations structure and in do_sendfile().
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

This patch removes xip_file_sendfile, the sendfile implementation for
xip without replacement. Those customers that use xip on s390 are not
using sendfile() as far as we know, and so far s390 is the only platform
this could potentially be used on so far.
Having sendfile is not a popular feature for execute in place file
systems, however we have a working implementation of splice_read() based
on fs/splice.c if anyone asks for it.
At this point in time, it does not seem preferable to merge
splice_read() for xip because it causes extra maintenence effort due to
code duplication and it requires struct page behind the xip memory
segment. We'd like to get rid of that in favor of supporting flash based
embedded platforms (Monta Vista work) soon.
Signed-off-by: NCarsten Otte <cotte@de.ibm.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Also add fs/splice.c as a kerneldoc target with a smaller blurb that
should be expanded to better explain the overview of splice.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

do_sendfile() prefers splice over sendfile, so it should not trigger
(directly, at least).
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

relay needs this for proper consumption handling, and the network
receive support needs it as well to lookup the sk_buff on pipe
release.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

We need to move even more stuff into the header so that folks can use
the splice_to_pipe() implementation instead of open-coding a lot of
pipe knowledge (see relay implementation), so move to our own header
file finally.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Acked-by: NTrond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

They can use generic_file_splice_read() instead. Since sys_sendfile() now
prefers that, there should be no change in behaviour.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

This patch makes sendfile prefer to use ->splice_read(), if it's
available in the file_operations structure.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

A bit of a cheat, it actually just copies the data to userspace. But
this makes the interface nice and symmetric and enables people to build
on splice, with room for future improvement in performance.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

For direct splicing (or private splicing), the output may not be a file.
So abstract out the handling into a specified actor function and put
the data in the splice_desc structure earlier, so we can build on top
of that.

This is the first step in better splice handling for drivers, and also
for implementing vmsplice _to_ user memory.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

bio_{,un}map_user no longer have any modular users.
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

scheduler debugging core: implement /proc/sched_debug and
/proc/<PID>/sched files for scheduler debugging.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

update delay-accounting to use CFS's precise stats.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

make use of CFS's precise accounting to drive /proc/<pid>/stat statistics.

this code was co-authored by:

 Balbir Singh <balbir@linux.vnet.ibm.com>
 Dmitry Adamushko <dmitry.adamushko@gmail.com>
 Ingo Molnar <mingo@elte.hu>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NDmitry Adamushko <dmitry.adamushko@gmail.com>

remove the SleepAVG field from /proc/<pid>/status, as
with the removal of the sleep-average code this value
no longer makes sense.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This reverts part of an earlier patch which tried to reclaim
gfs2_bufdata structures too early and resulted in a "use after free"
case (this bit from me). Also a change to not write out log headers
unless we really need to (in the case of flushing nothing we don't need
a header) from Bob.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>
Signed-off-by: NBob Peterson <rpeterso@redhat.com>

Add two more output fields (lkb_flags and rsb nodeid) to the new debugfs
file that dumps one lock per line.  Also, dump all locks instead of just
mastered locks.  Accordingly, use a suffix of _locks instead of _master.
Signed-off-by: NDavid Teigland <teigland@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

GFS2 has been passing i_mode within NFS File Handle. Other than the
wrong assumption that there is always room for this extra 16 bit value,
the current gfs2_get_dentry doesn't really need the i_mode to work
correctly. Note that GFS2 NFS code does go thru the same lookup code
path as direct file access route (where the mode is obtained from name
lookup) but gfs2_get_dentry() is coded for different purpose. It is not
used during lookup time. It is part of the file access procedure call.
When the call is invoked, if on-disk inode is not in-memory, it has to
be read-in. This makes i_mode passing a useless overhead.
Signed-off-by: NS. Wendy Cheng <wcheng@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

GFS2 lookup code doesn't ask for inode shared glock. This implies during
in-memory inode creation for existing file, GFS2 will not disk-read in
the inode contents. This leaves no_formal_ino un-initialized during
lookup time. The un-initialized no_formal_ino is subsequently encoded
into file handle. Clients will get ESTALE error whenever it tries to
access these files.
Signed-off-by: NS. Wendy Cheng <wcheng@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

The kernel threads in gfs2, namely gfs2_scand, gfs2_logd, gfs2_quotad,
gfs2_glockd, gfs2_recoverd weren't doing anything when the suspend
mechanism was trying to freeze them.

I put in calls to refrigerator() in the loops for all the daemons and
suspend works as expected.
Signed-off-by: NAbhijith Das <adas@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This patch is for bugzilla bug #245663.  This crosswrites a fix from
gfs1 (bz #210369) so that the mount options are reset properly upon
remount.  This was tested on system trin-10.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This should have been part of the NFS patch #1 but somehow I missed it
when packaging the patches. It is not a critical issue as the others (I
hope). RHEL 5.1 31.el5 kernel runs fine without this change.

Our truncate code is chopped into two parts, one for vfs inode changes
(in vmtruncate()) and one of gfs inode (in gfs2_truncatei()). These two
operatons are, unfortunately, not atomic. So it could happens that
vmtruncate() succeeds (inode->i_size is changed) but gfs2_truncatei
fails (say kernel temporarily out of memory). This would leave gfs inode
i_di.di_size out of sync with vfs inode i_size. It will later confuse
gfs2_commit_write() if a write is issued. Last time I checked, it will
cause file corruption.
Signed-off-by: NS. Wendy Cheng <wcheng@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This patch fixes Red Hat bz#245892

Opening a tcp connection from a cluster member to another cluster member
targeting the dlm port it is enough to stop every dlm operation in the cluster.
This means that GFS and rgmanager will hang.
Signed-Off-By: NPatrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>