Wire up *at syscalls.

This patch has been tested on ppc64 (using glibc's testsuite, both 32bit
and 64bit), and compile-tested for ppc32 (I have currently no ppc32 system
available, but I expect no problems).
Signed-off-by: NAndreas Schwab <schwab@suse.de>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Use the new find_get_pages_contig() to potentially look up the entire
splice range in one single call. This speeds up generic_file_splice_read()
quite a bit.
Signed-off-by: NJens Axboe <axboe@suse.de>

Avoids doing useless work, when the file is fully cached.
Signed-off-by: NJens Axboe <axboe@suse.de>

This patch addresses a flaw in LSM, where there is no mediation of readv()
and writev() in for 32-bit compatible apps using a 64-bit kernel.

This bug was discovered and fixed initially in the native readv/writev
code [1], but was not fixed in the compat code.  Thanks to Al for spotting
this one.

  [1] http://lwn.net/Articles/154282/Signed-off-by: NJames Morris <jmorris@namei.org>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

All modifications of ->i_flags in inodes that might be visible to
somebody else must be under ->i_mutex.  That patch fixes ext3 ioctl()
setting S_APPEND and friends.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

sbi->s_group_desc is an array of pointers to buffer_head.  memcpy() of
buffer size from address of buffer_head is a bad idea - it will generate
junk in any case, may oops if buffer_head is close to the end of slab
page and next page is not mapped and isn't what was intended there.
IOW, ->b_data is missing in that call.  Fortunately, result doesn't go
into the primary on-disk data structures, so only backup ones get crap
written to them; that had allowed this bug to remain unnoticed until
now.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

We need these for people writing their own ->splice_read/write hooks.
Signed-off-by: NJens Axboe <axboe@suse.de>

sys_splice() moves data to/from pipes with a file input/output. sys_vmsplice()
moves data to a pipe, with the input being a user address range instead.

This uses an approach suggested by Linus, where we can hold partial ranges
inside the pages[] map. Hopefully this will be useful for network
receive support as well.
Signed-off-by: NJens Axboe <axboe@suse.de>

BKL does not protect against races if the task may sleep between
checking and setting a value.  So move checking of file->private_data
near to setting it in fuse_fill_super().

Found by Al Viro.
Signed-off-by: NMiklos Szeredi <miklos@szeredi.hu>

A deadlock was possible, when the last reference to the superblock was
held due to a background request containing a file reference.

Releasing the file would release the vfsmount which in turn would
release the superblock.  Since sbput_sem is held during the fput() and
fuse_put_super() tries to acquire this same semaphore, a deadlock
results.

The solution is to move the fput() outside the region protected by
sbput_sem.
Signed-off-by: NMiklos Szeredi <miklos@szeredi.hu>

This reverts 73ce8355 commit.

It was wrong, because it didn't take into account the requirement,
that iput() for background requests must be performed synchronously
with ->put_super(), otherwise active inodes may remain after unmount.

The right solution is to keep the sbput_sem and perform iput() within
the locked region, but move fput() outside sbput_sem.
Signed-off-by: NMiklos Szeredi <miklos@szeredi.hu>

Make the move_from_pipe() actors return number of bytes processed, then
move_from_pipe() can decide more cleverly when to move on to the next
buffer.

This fixes problems with pipe offset and differing file offset.
Signed-off-by: NJens Axboe <axboe@suse.de>

Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NJens Axboe <axboe@suse.de>

Signed-off-by: NDave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Signed-off-by: NSteve French <sfrench@us.ibm.com>

reiserfs_cache_default_acl() should return whether we successfully found
the acl or not.  We have to return correct value even if reiserfs_get_acl()
returns error code and not just 0.  Otherwise callers such as
reiserfs_mkdir() can unnecessarily lock the xattrs and later functions such
as reiserfs_new_inode() fail to notice that we have already taken the lock
and try to take it again with obvious consequences.
Signed-off-by: NJan Kara <jack@suse.cz>
Cc: <reiserfs-dev@namesys.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

in directory

Also includes first part of fix to compensate for servers which forget
to return . and .. as well as updates to changelog and cifs readme.
Signed-off-by: NSteve French <sfrench@us.ibm.com>

thread creation and teardown.

It does not move the cifsd thread handling to kthread due to problems
found in testing with wakeup of threads blocked in the socket peek api,
but the other cifs kernel threads now use kthread.
Also cleanup cifs_init to properly unwind when thread creation fails.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Unless Posix paths have been negotiated, the backslash, "\", is not a valid
character in a path component.
Signed-off-by: NDave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: NSteve French  <sfrench@us.ibm.com>

building of full path) to avoid hang rename/readdir hang

Reported by Alan Tyson
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Signed-off-by: NJens Axboe <axboe@suse.de>

Local variable res was initialized to 0 - no check needed here.
Signed-off-by: NCarsten Otte <cotte@de.ibm.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Convert a for-loop that explicitly references "NR_CPUS" into the
potentially more efficient for_each_possible_cpu() construct.
Signed-off-by: NJohn Hawkes <hawkes@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

If the call to nfs_intent_set_file() fails to open a file in
nfs4_proc_create(), we should return an error.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

There are places in the kernel where we look up files in fd tables and
access the file structure without holding refereces to the file.  So, we
need special care to avoid the race between looking up files in the fd
table and tearing down of the file in another CPU.  Otherwise, one might
see a NULL f_dentry or such torn down version of the file.  This patch
fixes those special places where such a race may happen.
Signed-off-by: NDipankar Sarma <dipankar@in.ibm.com>
Acked-by: N"Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

In kernel bugzilla #6248 (http://bugzilla.kernel.org/show_bug.cgi?id=6248),
Adrian Bunk <bunk@stusta.de> notes that CONFIG_HUGETLBFS is missing Kconfig
help text.
Signed-off-by: NArthur Othieno <apgo@patchbomb.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

While we can currently walk through thread groups, process groups, and
sessions with just the rcu_read_lock, this opens the door to walking the
entire task list.

We already have all of the other RCU guarantees so there is no cost in
doing this, this should be enough so that proc can stop taking the
tasklist lock during readdir.

prev_task was killed because it has no users, and using it will miss new
tasks when doing an rcu traversal.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Since ->map() no longer locks the page, we need to adjust the handling
of those pages (and stealing) a little. This now passes full regressions
again.
Signed-off-by: NJens Axboe <axboe@suse.de>

- We need to adjust *ppos for writes as well.
- Copy back modified offset value if one was passed in, similar to
  what sendfile does.
Signed-off-by: NJens Axboe <axboe@suse.de>

We need to ensure that we only drop a lock that is ordered last, to avoid
ABBA deadlocks with competing processes.
Signed-off-by: NJens Axboe <axboe@suse.de>

- generic_file_splice_read() more readable and correct
- Don't bail on page allocation with NONBLOCK set, just don't allow
  direct blocking on IO (eg lock_page).
Signed-off-by: NJens Axboe <axboe@suse.de>

We need to check i_size after doing a blocking readpage.
Signed-off-by: NJens Axboe <axboe@suse.de>

Came up through a quick grep for other cases similar to the ftruncate()
one in commit 0a489cb3.

Also, add a comment, so that people who read the code understand why we
do what looks like a no-op.

(Again, this won't actually matter to any sane user, since libc will
save and restore the register gcc stomps on, but it's still wrong to
stomp on it)
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Gcc thinks it owns the incoming argument stack, but that's not true for
"asmlinkage" functions, and it corrupts the caller-set-up argument stack
when it pushes the third argument onto the stack.  Which can result in
%ebx getting corrupted in user space.

Now, normally nobody sane would ever notice, since libc will save and
restore %ebx anyway over the system call, but it's still wrong.

I'd much rather have "asmlinkage" tell gcc directly that it doesn't own
the stack, but no such attribute exists, so we're stuck with our hacky
manual "prevent_tail_call()" macro once more (we've had the same issue
before with sys_waitpid() and sys_wait4()).

Thanks to Hans-Werner Hilse <hilse@sub.uni-goettingen.de> for reporting
the issue and testing the fix.
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Missed unlock_super()call is added in error condition code path.
Signed-off-by: NLeonid Ananiev <leonid.i.ananiev@intel.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

As noted further on the this file, some block devices have a / in their
name, so fix the "block:..." symlink name the same as the /sys/block name.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

[BLOCK] delay all uevents until partition table is scanned

Here we delay the annoucement of all block device events until the
disk's partition table is scanned and all partition devices are already
created and sysfs is populated.

We have a bunch of old bugs for removable storage handling where we
probe successfully for a filesystem on the raw disk, but at the
same time the kernel recognizes a partition table and creates partition
devices.
Currently there is no sane way to tell if partitions will show up or not
at the time the disk device is announced to userspace. With the delayed
events we can simply skip any probe for a filesystem on the raw disk when
we find already present partitions.
Signed-off-by: NKay Sievers <kay.sievers@suse.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

It works like this:
  Open the file
  Read all the contents.
  Call poll requesting POLLERR or POLLPRI (so select/exceptfds works)
  When poll returns,
     close the file and go to top of loop.
   or lseek to start of file and go back to the 'read'.

Events are signaled by an object manager calling
   sysfs_notify(kobj, dir, attr);

If the dir is non-NULL, it is used to find a subdirectory which
contains the attribute (presumably created by sysfs_create_group).

This has a cost of one int  per attribute, one wait_queuehead per kobject,
one int per open file.

The name "sysfs_notify" may be confused with the inotify
functionality.  Maybe it would be nice to support inotify for sysfs
attributes as well?

This patch also uses sysfs_notify to allow /sys/block/md*/md/sync_action
to be pollable
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>