Both iput() and put_rpccred() might allocate memory under certain
circumstances, so make sure that we don't recurse and deadlock...
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

There is no danger of deadlock should the allocation trigger page
writeback.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

There is no point in looping if we're out of memory.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

We do not want to have the state recovery thread kick off and wait for a
memory reclaim, since that may deadlock when the writebacks end up
waiting for the state recovery thread to complete.

The safe thing is therefore to use GFP_NOFS in all open, close,
delegation return, lock, etc. operations that may be called by the
state recovery thread.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

I'm about to change task->tk_start from a jiffies value to a ktime_t
value in order to make RPC RTT reporting more precise.

Recently (commit dc96aef9) nfs4_renew_done() started to reference
task->tk_start so that a jiffies value no longer had to be passed
from nfs4_proc_async_renew().  This allowed the calldata to point to
an nfs_client instead.

Changing task->tk_start to a ktime_t value makes it effectively
useless for renew timestamps, so we need to restore the pre-dc96aef9
logic that provided a jiffies "start" timestamp to nfs4_renew_done().

Both an nfs_client pointer and a timestamp need to be passed to
nfs4_renew_done(), so create a new nfs_renewdata structure that
contains both, resembling what is already done for delegreturn,
lock, and unlock.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Clean up:

fs/nfs/iostat.h: In function ‘nfs_add_server_stats’:
fs/nfs/iostat.h:41: warning: comparison between signed and unsigned integer expressions
fs/nfs/iostat.h:41: warning: comparison between signed and unsigned integer expressions
fs/nfs/iostat.h:41: warning: comparison between signed and unsigned integer expressions
fs/nfs/iostat.h:41: warning: comparison between signed and unsigned integer expressions

Commit fce22848 replaced the open-coded per-cpu logic in several
functions in fs/nfs/iostat.h with a single invocation of
this_cpu_ptr().  This macro assumes its second argument is signed,
not unsigned.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Clean up: fscache_uniq takes a string, so it should be included
with the other string mount option definitions, by convention.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Seen with -Wextra:

/home/cel/linux/fs/nfs/fscache.c: In function ‘__nfs_readpages_from_fscache’:
/home/cel/linux/fs/nfs/fscache.c:479: warning: comparison between signed and unsigned integer expressions

The comparison implicitly converts "int" to "unsigned", making it
safe.  But there's no need for the implicit type conversions here, and
the dfprintk() already uses a "%u" formatter for "npages."  Better to
reduce confusion.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Reviewed-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

If the server has given us a delegation on a file, we _know_ that we can
cache the attribute information even when the user has specified 'noac'.
Reviewed-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

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

Use the new helper functions instead of open coding.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Keep a global count of how many referrals that the current task has
traversed on a path lookup. Return ELOOP if the count exceeds
MAX_NESTED_LINKS.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

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

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

Move the O_EXCL open handling into _nfs4_do_open() where it belongs. Doing
so also allows us to reuse the struct fattr from the opendata.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

All we really want is the ability to retrieve the root file handle. We no
longer need the ability to walk down the path, since that is now done in
nfs_follow_remote_path().
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

NFS Filehandles and struct fattr are really too large to be allocated on
the stack. This patch adds in a couple of helper functions to allocate them
dynamically instead.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

inotify_new_group() receives a get_uid-ed user_struct and saves the
reference on group->inotify_data.user.  The problem is that free_uid() is
never called on it.

Issue seem to be introduced by 63c882a0 (inotify: reimplement inotify
using fsnotify) after 2.6.30.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Eric Paris <eparis@parisplace.org>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NEric Paris <eparis@redhat.com>

There is a race in the inotify add/rm watch code.  A task can find and
remove a mark which doesn't have all of it's references.  This can
result in a use after free/double free situation.

Task A					Task B
------------				-----------
inotify_new_watch()
 allocate a mark (refcnt == 1)
 add it to the idr
					inotify_rm_watch()
					 inotify_remove_from_idr()
					  fsnotify_put_mark()
					      refcnt hits 0, free
 take reference because we are on idr
 [at this point it is a use after free]
 [time goes on]
 refcnt may hit 0 again, double free

The fix is to take the reference BEFORE the object can be found in the
idr.
Signed-off-by: NEric Paris <eparis@redhat.com>
Cc: <stable@kernel.org>

inotify_add_watch explictly frees the unused inode mark, but it can just
use the generic code.  Just do that.
Signed-off-by: NEric Paris <eparis@redhat.com>