call->async_workfn() can take an afs_call* arg rather than a work_struct* as
the functions assigned there are now called from afs_async_workfn() which has
to call container_of() anyway.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Nathaniel Wesley Filardo <nwf@cs.jhu.edu>
Reviewed-by: Tejun Heo <tj@kernel.org>
At present, it is not possible to successfully unload the kafs module if there
are outstanding async outgoing calls (those made with afs_make_call()). This
appears to be due to the changes introduced by:
commit 059499453a
Author: Tejun Heo <tj@kernel.org>
Date: Fri Mar 7 10:24:50 2014 -0500
Subject: afs: don't use PREPARE_WORK
which didn't go far enough. The problem is due to:
(1) The aforementioned commit introduced a separate handler function pointer
in the call, call->async_workfn, in addition to the original workqueue
item, call->async_work, for asynchronous operations because workqueues
subsystem cannot handle the workqueue item pointer being changed whilst
the item is queued or being processed.
(2) afs_async_workfn() was introduced in that commit to be the callback for
call->async_work. Its sole purpose is to run whatever call->async_workfn
points to.
(3) call->async_workfn is only used from afs_async_workfn(), which is only
set on async_work by afs_collect_incoming_call() - ie. for incoming
calls.
(4) call->async_workfn is *not* set by afs_make_call() when outgoing calls are
made, and call->async_work is set afs_process_async_call() - and not
afs_async_workfn().
(5) afs_process_async_call() now changes call->async_workfn rather than
call->async_work to point to afs_delete_async_call() to clean up, but this
is only effective for incoming calls because call->async_work does not
point to afs_async_workfn() for outgoing calls.
(6) Because, for incoming calls, call->async_work remains pointing to
afs_process_async_call() this results in an infinite loop.
Instead, make the workqueue uniformly vector through call->async_workfn, via
afs_async_workfn() and simply initialise call->async_workfn to point to
afs_process_async_call() in afs_make_call().
Signed-off-by: Nathaniel Wesley Filardo <nwf@cs.jhu.edu>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Tejun Heo <tj@kernel.org>
Split afs_end_call() into two pieces, one of which is identical to code in
afs_process_async_call(). Replace the latter with a call to the first part of
afs_end_call().
Signed-off-by: Nathaniel Wesley Filardo <nwf@cs.jhu.edu>
Signed-off-by: David Howells <dhowells@redhat.com>
Fix the cache manager RPC service handlers. The afs_send_empty_reply() and
afs_send_simple_reply() functions:
(a) Kill the call and free up the buffers associated with it if they fail.
(b) Return with call intact if it they succeed.
However, none of the callers actually check the result or clean up if
successful - and may use the now non-existent data if it fails.
This was detected by Dan Carpenter using a static checker:
The patch 08e0e7c82e: "[AF_RXRPC]: Make the in-kernel AFS
filesystem use AF_RXRPC." from Apr 26, 2007, leads to the following
static checker warning:
"fs/afs/cmservice.c:155 SRXAFSCB_CallBack()
warn: 'call' was already freed."
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Howells <dhowells@redhat.com>
PREPARE_[DELAYED_]WORK() are being phased out. They have few users
and a nasty surprise in terms of reentrancy guarantee as workqueue
considers work items to be different if they don't have the same work
function.
afs_call->async_work is multiplexed with multiple work functions.
Introduce afs_async_workfn() which invokes afs_call->async_workfn and
always use it as the work function and update the users to set the
->async_workfn field instead of overriding the work function using
PREPARE_WORK().
It would probably be best to route this with other related updates
through the workqueue tree.
Compile tested.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Cc: linux-afs@lists.infradead.org
When writing files to afs I sometimes hit a BUG:
kernel BUG at fs/afs/rxrpc.c:179!
With a backtrace of:
afs_free_call
afs_make_call
afs_fs_store_data
afs_vnode_store_data
afs_write_back_from_locked_page
afs_writepages_region
afs_writepages
The cause is:
ASSERT(skb_queue_empty(&call->rx_queue));
Looking at a tcpdump of the session the abort happens because we
are exceeding our disk quota:
rx abort fs reply store-data error diskquota exceeded (32)
So the abort error is valid. We hit the BUG because we haven't
freed all the resources for the call.
By freeing any skbs in call->rx_queue before calling afs_free_call
we avoid hitting leaking memory and avoid hitting the BUG.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
flush_scheduled_work() is going away. afs needs to make sure all the
works it has queued have finished before being unloaded and there can
be arbitrary number of pending works. Add afs_wq and use it as the
flush domain instead of the system workqueue.
Also, convert cancel_delayed_work() + flush_scheduled_work() to
cancel_delayed_work_sync() in afs_mntpt_kill_timer().
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: linux-afs@lists.infradead.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We can clean up the work queue on this error path. This function is
called from afs_init().
Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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>
This patch contains the following possible cleanups:
- make the following needlessly global functions static:
- rxrpc.c: afs_send_pages()
- vlocation.c: afs_vlocation_queue_for_updates()
- write.c: afs_writepages_region()
- make the following needlessly global variables static:
- mntpt.c: afs_mntpt_expiry_timeout
- proc.c: afs_vlocation_states[]
- server.c: afs_server_timeout
- vlocation.c: afs_vlocation_timeout
- vlocation.c: afs_vlocation_update_timeout
- #if 0 the following unused function:
- cell.c: afs_get_cell_maybe()
- #if 0 the following unused variables:
- callback.c: afs_vnode_update_timeout
- cmservice.c: struct afs_cm_workqueue
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix afs_send_simple_reply() to accept a greater-than-zero return value from
rxrpc_kernel_send_data() as being a successful return rather than thinking it
an error and aborting the call.
rxrpc_kernel_send_data() previously returned zero incorrectly when it worked
successfully, but has been patched to return the number of bytes it
transmitted.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Further fixes for AFS write support:
(1) The afs_send_pages() outer loop must do an extra iteration if it ends
with 'first == last' because 'last' is inclusive in the page set
otherwise it fails to send the last page and complete the RxRPC op under
some circumstances.
(2) Similarly, the outer loop in afs_pages_written_back() must also do an
extra iteration if it ends with 'first == last', otherwise it fails to
clear PG_writeback on the last page under some circumstances.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Implement support for writing to regular AFS files, including:
(1) write
(2) truncate
(3) fsync, fdatasync
(4) chmod, chown, chgrp, utime.
AFS writeback attempts to batch writes into as chunks as large as it can manage
up to the point that it writes back 65535 pages in one chunk or it meets a
locked page.
Furthermore, if a page has been written to using a particular key, then should
another write to that page use some other key, the first write will be flushed
before the second is allowed to take place. If the first write fails due to a
security error, then the page will be scrapped and reread before the second
write takes place.
If a page is dirty and the callback on it is broken by the server, then the
dirty data is not discarded (same behaviour as NFS).
Shared-writable mappings are not supported by this patch.
[akpm@linux-foundation.org: fix a bunch of warnings]
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fixes for various arch compilation problems:
(*) Missing module exports.
(*) Variable name collision when rxkad and af_rxrpc both built in
(rxrpc_debug).
(*) Large constant representation problem (AFS_UUID_TO_UNIX_TIME).
(*) Configuration dependencies.
(*) printk() format warnings.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add support for the CB.GetCapabilities operation with which the fileserver can
ask the client for the following information:
(1) The list of network interfaces it has available as IPv4 address + netmask
plus the MTUs.
(2) The client's UUID.
(3) The extended capabilities of the client, for which the only current one
is unified error mapping (abort code interpretation).
To support this, the patch adds the following routines to AFS:
(1) A function to iterate through all the network interfaces using RTNETLINK
to extract IPv4 addresses and MTUs.
(2) A function to iterate through all the network interfaces using RTNETLINK
to pull out the MAC address of the lowest index interface to use in UUID
construction.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add security support to the AFS filesystem. Kerberos IV tickets are added as
RxRPC keys are added to the session keyring with the klog program. open() and
other VFS operations then find this ticket with request_key() and either use
it immediately (eg: mkdir, unlink) or attach it to a file descriptor (open).
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make the in-kernel AFS filesystem use AF_RXRPC instead of the old RxRPC code.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
