nfs: rename the nfs_async_rename_done tracepoint

We do async renames in other cases besides sillyrenames now. This
tracepoint name is now misleading.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS: Fix a race in nfs_call_unlink()

We should check that the filehandles match before transferring the
sillyrename data to the newly looked-up dentry in case the name was
reused on the server.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFSv4.1 mark qualified async operations as MOVEABLE tasks

Mark async operations such as RENAME, REMOVE, COMMIT MOVEABLE
for the nfsv4.1+ sessions.

Fixes: 85e39feead948 ("NFSv4.1 identify and mark RPC tasks that can move between transports")
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS: Ensure rpc_run_task() cannot fail in nfs_async_rename()

Ensure the call to rpc_run_task() cannot fail by preallocating the
rpc_task.

Fixes: 910ad38697d9 ("NFS: Fix memory allocation in rpc_alloc_task()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: Fix open coded versions of nfs_set_cache_invalid()

nfs_set_cache_invalid() has code to handle delegations, and other
optimisations, so let's use it when appropriate.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS: Avoid referencing the cred twice in async rename/unlink

In both async rename and rename, we take a reference to the
cred in the call arguments.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

fsnotify: move fsnotify_nameremove() hook out of d_delete()

d_delete() was piggy backed for the fsnotify_nameremove() hook when
in fact not all callers of d_delete() care about fsnotify events.

For all callers of d_delete() that may be interested in fsnotify events,
we made sure to call one of fsnotify_{unlink,rmdir}() hooks before
calling d_delete().

Now we can move the fsnotify_nameremove() call from d_delete() to the
fsnotify_{unlink,rmdir}() hooks.

Two explicit calls to fsnotify_nameremove() from nfs/afs sillyrename
are also removed. This will cause a change of behavior - nfs/afs will
NOT generate an fsnotify delete event when renaming over a positive
dentry. This change is desirable, because it is consistent with the
behavior of all other filesystems.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

NFS: Fix up documentation warnings

Fix up some compiler warnings about function parameters, etc not being
correctly described or formatted.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: remove unnecessary test for IS_ERR(cred)

As gte_current_cred() cannot return an error,
this test is not necessary.
It hasn't been necessary for years, but it wasn't so obvious
before.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS/NFSD/SUNRPC: replace generic creds with 'struct cred'.

SUNRPC has two sorts of credentials, both of which appear as
"struct rpc_cred".
There are "generic credentials" which are supplied by clients
such as NFS and passed in 'struct rpc_message' to indicate
which user should be used to authorize the request, and there
are low-level credentials such as AUTH_NULL, AUTH_UNIX, AUTH_GSS
which describe the credential to be sent over the wires.

This patch replaces all the generic credentials by 'struct cred'
pointers - the credential structure used throughout Linux.

For machine credentials, there is a special 'struct cred *' pointer
which is statically allocated and recognized where needed as
having a special meaning. A look-up of a low-level cred will
map this to a machine credential.

Signed-off-by: NeilBrown <neilb@suse.com>
Acked-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS: Fix up sillyrename()

Ensure that we register the fact that the inode ctime has changed.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFSv4: Fix sillyrename to return the delegation when appropriate

Ensure that we pass down the inode of the file being deleted so
that we can return any delegation being held.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS: Add a delegation return into nfs4_proc_unlink_setup()

Ensure that when we do finally delete the file, then we return the
delegation.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

NFS: Move delegation recall into the NFSv4 callback for rename_setup()

Move the delegation recall out of the generic code, and into the NFSv4
specific callback.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

NFS: nfs_rename() - revalidate directories on -ERESTARTSYS

An interrupted rename will leave the old dentry behind if the rename
succeeds. Fix this by forcing a lookup the next time through
->d_revalidate.

A previous attempt at solving this problem took the approach to complete
the work of the rename asynchronously, however that approach was wrong
since it would allow the d_move() to occur after the directory's i_mutex
had been dropped by the original process.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

qstr: constify instances in nfs

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

nfs: per-name sillyunlink exclusion

use d_alloc_parallel() for sillyunlink/lookup exclusion and
explicit rwsem (nfs_rmdir() being a writer and nfs_call_unlink() -
a reader) for rmdir/sillyunlink one.

That ought to make lookup/readdir/!O_CREAT atomic_open really
parallel on NFS.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

nfs: missing wakeup in nfs_unblock_sillyrename()

will be needed as soon as lookups are not serialized by ->i_mutex

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

VFS: normal filesystems (and lustre): d_inode() annotations

that's the bulk of filesystem drivers dealing with inodes of their own

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

nfs: emit a fsnotify_nameremove call in sillyrename codepath

If a file is sillyrenamed, then the generic vfs_unlink code will skip
emitting fsnotify events for it.

This patch has the sillyrename code do that instead.

In truth this is a little bit odd since we aren't actually removing the
dentry per-se, but renaming it. Still, this is probably the right thing
to do since it's what userland apps expect to see when an unlink()
occurs or some file is renamed on top of the dentry.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Tested-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

nfs: make nfs_async_rename non-static

...and move the prototype for nfs_sillyrename to internal.h.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Tested-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

nfs: abstract out code needed to complete a sillyrename

The async rename code is currently "polluted" with some parts that are
really just for sillyrenames. Add a new "complete" operation vector to
the nfs_renamedata to separate out the stuff that just needs to be done
for a sillyrename.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Tested-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

nfs: Remove useless 'error' assignment

the 'error' variable was been assigned twice in vain.

Signed-off-by: Geyslan G. Bem <geyslan@gmail.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

nfs: use %p[dD] instead of open-coded (and often racy) equivalents

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

NFS: Ensure that rmdir() waits for sillyrenames to complete

If an NFS client does

mkdir("dir");
fd = open("dir/file");
unlink("dir/file");
close(fd);
rmdir("dir");

then the asynchronous nature of the sillyrename operation means that
we can end up getting EBUSY for the rmdir() in the above test. Fix
that by ensuring that we wait for any in-progress sillyrenames
before sending the rmdir() to the server.

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

NFS: Add tracepoints for debugging NFS rename and sillyrename issues

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

NFS: Clean up nfs_sillyrename()

Optimise for the case where we only do one lookup.
Clean up the code so it is obvious that silly[] is not a dynamic array.

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

helper for reading ->d_count

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

NFS: Don't allow NFS silly-renamed files to be deleted, no signal

Commit 73ca100 broke the code that prevents the client from deleting
a silly renamed dentry. This affected "delete on last close"
semantics as after that commit, nothing prevented removal of
silly-renamed files. As a result, a process holding a file open
could easily get an ESTALE on the file in a directory where some
other process issued 'rm -rf some_dir_containing_the_file' twice.
Before the commit, any attempt at unlinking silly renamed files would
fail inside may_delete() with -EBUSY because of the
DCACHE_NFSFS_RENAMED flag. The following testcase demonstrates
the problem:
tail -f /nfsmnt/dir/file &
rm -rf /nfsmnt/dir
rm -rf /nfsmnt/dir
# second removal does not fail, 'tail' process receives ESTALE

The problem with the above commit is that it unhashes the old and
new dentries from the lookup path, even in the normal case when
a signal is not encountered and it would have been safe to call
d_move. Unfortunately the old dentry has the special
DCACHE_NFSFS_RENAMED flag set on it. Unhashing has the
side-effect that future lookups call d_alloc(), allocating a new
dentry without the special flag for any silly-renamed files. As a
result, subsequent calls to unlink silly renamed files do not fail
but allow the removal to go through. This will result in ESTALE
errors for any other process doing operations on the file.

To fix this, go back to using d_move on success.
For the signal case, it's unclear what we may safely do beyond d_drop.

Reported-by: Dave Wysochanski <dwysocha@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Cc: stable@vger.kernel.org

nfs: remove kfree() redundant null checks

smatch analysis:

fs/nfs/getroot.c:130 nfs_get_root() info: redundant null
check on name calling kfree()

fs/nfs/unlink.c:272 nfs_async_unlink() info: redundant null
check on devname_garbage calling kfree()

Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: linux-nfs@vger.kernel.org
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Revert "NFS: add nfs_sb_deactive_async to avoid deadlock"

This reverts commit 324d003b0cd82151adbaecefef57b73f7959a469.

The deadlock turned out to be caused by a workqueue limitation that has
now been worked around in the RPC code (see comment in rpc_free_task).

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

NFS: add nfs_sb_deactive_async to avoid deadlock

Use nfs_sb_deactive_async instead of nfs_sb_deactive when in a workqueue
context. This avoids a deadlock where rpc_shutdown_client loops forever
in a workqueue kworker context, trying to kill all RPC tasks associated with
the client, while one or more of these tasks have already been assigned to the
same kworker (and will never run rpc_exit_task).

This approach is needed because RPC tasks that have already been assigned
to a kworker by queue_work cannot be canceled, as explained in the comment
for workqueue.c:insert_wq_barrier.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
[Trond: add module_get/put.]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Create a return_delegation rpc op

Delegations are a v4 feature, so push return_delegation out of the
generic client by creating a new rpc_op and renaming the old function to
be in the nfs v4 "namespace"

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Remove nfs4_setup_sequence from generic rename code

This is an NFS v4 specific operation, so it belongs in the NFS v4 code
and not the generic client.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Remove nfs4_setup_sequence from generic unlink code

This is an NFS v4 specific operation, so it belongs in the NFS v4 code
and not the generic client.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Fix a number of sparse warnings

Fix a number of "warning: symbol 'foo' was not declared. Should it be
static?" conditions.

Fix 2 cases of "warning: Using plain integer as NULL pointer"

fs/nfs/delegation.c:263:31: warning: restricted fmode_t degrades to integer
- We want to allow upgrades to a WRITE delegation, but should otherwise
consider servers that hand out duplicate delegations to be borken.

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

NFSv41: Add a new helper nfs4_init_sequence()

Clean up

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

NFS: Get rid of nfs_restart_rpc()

It can trivially be replaced with rpc_restart_call_prepare.

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

nfs: don't use d_move in nfs_async_rename_done

If the task that initiated the sillyrename ends up being killed by a
fatal signal, then it will eventually return back to userspace and end
up releasing the i_mutex. d_move however needs to be done while holding
the i_mutex.

Instead of using d_move here, just unhash the old and new dentries to
prevent them from being found by lookups. With this change though, the
dentries are now incorrect post-rename and do not reflect the actual
name of the file on the server. I'm proceeding under the assumption
that since they are unhashed that this isn't really a problem.

In order for the sillydelete to still work though, the dname must be
copied earlier when setting up the sillydelete info, and the name must
be recopied if the sillydelete info has to be moved to a new dentry.

Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

nfs: document nfsv4 sillyrename issues

Somebody working on this code asked what the deal was with NFSv4, since
this comment notes that it's v2/v3's statelessness that requires
sillyrename. Shouldn't hurt to document the answer.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

nfs: store devname at disconnected NFS roots

part 2: make sure that disconnected roots have corresponding mnt_devname
values stashed into them.

Have nfs*_get_root() stuff a copy of devname into ->d_fsdata of the
found root, provided that it is disconnected.

Have ->d_release() free it when dentry goes away.

Have the places where NFS uses ->d_fsdata for sillyrename (and that
can *never* happen to a disconnected root - dentry will be attached
to its parent) free old devname copies if they find those.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

SUNRPC: Close a race in __rpc_wait_for_completion_task()

Although they run as rpciod background tasks, under normal operation
(i.e. no SIGKILL), functions like nfs_sillyrename(), nfs4_proc_unlck()
and nfs4_do_close() want to be fully synchronous. This means that when we
exit, we want all references to the rpc_task to be gone, and we want
any dentry references etc. held by that task to be released.

For this reason these functions call __rpc_wait_for_completion_task(),
followed by rpc_put_task() in the expectation that the latter will be
releasing the last reference to the rpc_task, and thus ensuring that the
callback_ops->rpc_release() has been called synchronously.

This patch fixes a race which exists due to the fact that
rpciod calls rpc_complete_task() (in order to wake up the callers of
__rpc_wait_for_completion_task()) and then subsequently calls
rpc_put_task() without ensuring that these two steps are done atomically.

In order to avoid adding new spin locks, the patch uses the existing
waitqueue spin lock to order the rpc_task reference count releases between
the waiting process and rpciod.
The common case where nobody is waiting for completion is optimised for by
checking if the RPC_TASK_ASYNC flag is cleared and/or if the rpc_task
reference count is 1: in those cases we drop trying to grab the spin lock,
and immediately free up the rpc_task.

Those few processes that need to put the rpc_task from inside an
asynchronous context and that do not care about ordering are given a new
helper: rpc_put_task_async().

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

fs: dcache scale dentry refcount

Make d_count non-atomic and protect it with d_lock. This allows us to ensure a
0 refcount dentry remains 0 without dcache_lock. It is also fairly natural when
we start protecting many other dentry members with d_lock.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>

NFSv4: Convert a few commas into semicolons...

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

a couple of open-coded ihold() introduced by nfs merge

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

NFSv4.1: keep seq_res.sr_slot as pointer rather than an index

Having to explicitly initialize sr_slotid to NFS4_MAX_SLOT_TABLE
resulted in numerous bugs. Keeping the current slot as a pointer
to the slot table is more straight forward and robust as it's
implicitly set up to NULL wherever the seq_res member is initialized
to zeroes.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Fix a use-after-free case in nfs_async_rename()

The call to nfs_async_rename_release() after rpc_run_task() is incorrect.
The rpc_run_task() is always guaranteed to call the ->rpc_release() method.

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

nfs: make sillyrename an async operation

A synchronous rename can be interrupted by a SIGKILL. If that happens
during a sillyrename operation, it's possible for the rename call to
be sent to the server, but the task exits before processing the
reply. If this happens, the sillyrenamed file won't get cleaned up
during nfs_dentry_iput and the server is left with a dangling .nfs* file
hanging around.

Fix this problem by turning sillyrename into an asynchronous operation
and have the task doing the sillyrename just wait on the reply. If the
task is killed before the sillyrename completes, it'll still proceed
to completion.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

nfs: move nfs_sillyrename to unlink.c

...since that's where most of the sillyrenaming code lives. A comment
block is added to the beginning as well to clarify how sillyrenaming
works. Also, make nfs_async_unlink static as nfs_sillyrename is the only
caller.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFSv4.1: Make nfs4_setup_sequence take a nfs_server argument

In anticipation of the day when we have per-filesystem sessions, and also
in order to allow the session to change in the event of a filesystem
migration event.

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

NFS: Reduce stack footprint of nfs_proc_remove()

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

NFS: Fix up the declaration of nfs4_restart_rpc when NFSv4 not configured

Also rename it: it is used in generic code, and so should not have a 'nfs4'
prefix.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFSv41: Clean up slot table management

We no longer need to maintain a distinction between nfs41_sequence_done and
nfs41_sequence_free_slot.

This fixes a number of slot table leakages in the NFSv4.1 code.

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

nfs41: call free slot from nfs4_restart_rpc

nfs41_sequence_free_slot can be called multiple times on SEQUENCE operation
errors.
No reason to inline nfs4_restart_rpc

Reported-by: Trond Myklebust <trond.myklebust@netapp.com>

nfs_writeback_done and nfs_readpage_retry call nfs4_restart_rpc outside the
error handler, and the slot is not freed prior to restarting in the rpc_prepare
state during session reset.

Fix this by moving the call to nfs41_sequence_free_slot from the error
path of nfs41_sequence_done into nfs4_restart_rpc, and by removing the test
for NFS4CLNT_SESSION_SETUP.
Always free slot and goto the rpc prepare state on async errors.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

nfs41: use rpc prepare call state for session reset

[nfs41: change nfs4_restart_rpc argument]
[nfs41: check for session not minorversion]
[nfs41: trigger the state manager for session reset]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[always define nfs4_restart_rpc]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

nfs41: unlink sequence setup/done support

Implement the rpc_call_prepare methods for
asynchronuos nfs rpcs, call nfs41_setup_sequence from
respective rpc_call_validate_args methods.

Call nfs4_sequence_done from respective rpc_call_done methods.

Note that we need to pass a pointer to the nfs_server in calls data
for passing on to nfs4_sequence_done.

Signed-off-by: Andy Adamson<andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[pnfs: client data server write validate and release]
Signed-off-by: Andy Adamson<andros@umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: separate free slot from sequence done]
[nfs41: sequence res use slotid]
[nfs41: remove SEQ4_STATUS_USE_TK_STATUS]
[nfs41: nfs4_sequence_free_slot use nfs_client for data server]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

nfs41: set up seq_res.sr_slotid

Initialize nfs4_sequence_res sr_slotid to NFS4_MAX_SLOT_TABLE.

[was nfs41: sequence res use slotid]
Signed-off-by: Andy Adamson <andros@netapp.com>
[pulled definition of struct nfs4_sequence_res.sr_slotid to here]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Clean up nfs_sb_active/nfs_sb_deactive

Instead of causing umount requests to block on server->active_wq while the
asynchronous sillyrename deletes are executing, we can use the sb->s_active
counter to obtain a reference to the super_block, and then release that
reference in nfs_async_unlink_release().

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

NFS: Ensure we call nfs_sb_deactive() after releasing the directory inode

In order to avoid the "Busy inodes after unmount" error message, we need to
ensure that nfs_async_unlink_release() releases the super block after the
call to nfs_free_unlinkdata().

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

SUNRPC: Add a helper rpcauth_lookup_generic_cred()

The NFSv4 protocol allows clients to negotiate security protocols on the
fly in the case where an administrator on the server changes the export
settings and/or in the case where we may have a filesystem migration event.

Instead of having the NFS client code cache credentials that are tied to a
particular AUTH method it is therefore preferable to have a generic credential
that can be converted into whatever AUTH is in use by the RPC client when
the read/write/sillyrename/... is put on the wire.

We do this by means of the new "generic" credential, which basically just
caches the minimal information that is needed to look up an RPCSEC_GSS,
AUTH_SYS, or AUTH_NULL credential.

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

NFS/SUNRPC: Convert all users of rpc_call_setup()

Replace use of rpc_call_setup() with rpc_init_task(), and in cases where we
need to initialise task->tk_action, with rpc_call_start().

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

SUNRPC: Clean up rpc_run_task

Make it use the new task initialiser structure instead of acting as a
wrapper.

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

NFS: Stop sillyname renames and unmounts from racing

Added an active/deactive mechanism to the nfs_server structure
allowing async operations to hold off umount until the
operations are done.

Signed-off-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Sillyrename: in the case of a race, check aliases are really positive

In nfs_do_call_unlink() we check that we haven't raced, and that lookup()
hasn't created an aliased dentry to our sillydeleted dentry. If somebody
has deleted the file on the server and the lookup() resulted in a negative
dentry, then ignore...

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

NFS: Fix a sillyrename race...

Ensure that readdir revalidates its data cache after blocking on
sillyrename.

Also fix a typo in nfs_do_call_unlink(): swap the ^= for an |=. The result
is the same, since we've already checked that the flag is unset, but it
makes the code more readable.

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

NFS: Fix a typo in nfs_call_unlink()

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

Avoid compile error in fs/nfs/unlink.c

Erez Zadok reports that certain configurations fail to build due to
schedule() TASK_[UN]INTERRUPTIBLE not being declared. Add proper
include files to fix.

Cc: Erez Zadok <ezk@cs.sunysb.edu>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

NFS: Fix a race in sillyrename

lookup() and sillyrename() can race one another because the sillyrename()
completion cannot take the parent directory's inode->i_mutex since the
latter may be held by whoever is calling dput().

We therefore have little option but to add extra locking to ensure that
nfs_lookup() and nfs_atomic_open() do not race with the sillyrename
completion.
If somebody has looked up the sillyrenamed file in the meantime, we just
transfer the sillydelete information to the new dentry.

Please refer to the bug-report at
http://bugzilla.linux-nfs.org/show_bug.cgi?id=150

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

NFS: Remove nfs_begin_data_update/nfs_end_data_update

The lower level routines in fs/nfs/proc.c, fs/nfs/nfs3proc.c and
fs/nfs/nfs4proc.c should already be dealing with the revalidation issues.

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

SUNRPC: Clean up the sillyrename code

Fix a couple of bugs:
- Don't rely on the parent dentry still being valid when the call completes.
Fixes a race with shrink_dcache_for_umount_subtree()

- Don't remove the file if the filehandle has been labelled as stale.

Fix a couple of inefficiencies
- Remove the global list of sillyrenamed files. Instead we can cache the
sillyrename information in the dentry->d_fsdata
- Move common code from unlink_setup/unlink_done into fs/nfs/unlink.c

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

NFS: kzalloc conversion in fs/nfs

this converts fs/nfs to kzalloc() usage.
compile tested with make allyesconfig

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

SUNRPC: Further cleanups

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

RPC: Clean up RPC task structure

Shrink the RPC task structure. Instead of storing separate pointers
for task->tk_exit and task->tk_release, put them in a structure.

Also pass the user data pointer as a parameter instead of passing it via
task->tk_calldata. This enables us to nest callbacks.

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

[PATCH] kfree cleanup: fs

This is the fs/ part of the big kfree cleanup patch.

Remove pointless checks for NULL prior to calling kfree() in fs/.

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!