Now that the reference counting on the callback thread is working as
expected, it uncovers another problem. Peter Staubach noticed while
testing that patch on an older kernel that he would occasionally see
this printk in rpc_register fire:
"RPC: failed to contact portmap (errno -512).
The NFSv4 callback thread is signaled by nfs_callback_down(), but never
flushes that signal. All of the shutdown processing is done with that
signal pending. This makes it fail the call to unregister the port with
the portmapper.
In actuality, this rpc_register call isn't necessary at all since the
port isn't actually registered with the portmapper anymore. Regardless,
there doesn't seem to be any reason to leave the signal pending while
the thread is being shut down and flushing it should generally silence
that printk.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Commit b2e895dbd8 #if 0'ed this code stating:
<-- snip -->
[PATCH] revert blockdev direct io back to 2.6.19 version
Andrew Vasquez is reporting as-iosched oopses and a 65% throughput
slowdown due to the recent special-casing of direct-io against
blockdevs. We don't know why either of these things are occurring.
The patch minimally reverts us back to the 2.6.19 code for a 2.6.20
release.
<-- snip -->
It has since been dead code, and unless someone wants to revive it now
it's time to remove it.
This patch also makes bio_release_pages() static again and removes the
ki_bio_count member from struct kiocb, reverting changes that had been
done for this dead code.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Jens Axboe <axboe@carl.home.kernel.dk>
This patch makes the needlessly global struct def_blk_aops static.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Jens Axboe <axboe@carl.home.kernel.dk>
Change -I include directives to find headers in the out-of-tree spot. This
allows a directory containing only xfs files to be built as:
SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:29878a
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Donald Douwsma <donaldd@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Makefile (and Kbuild) would include Makefile-linux-26 I doubt XFS will
really still compile on 2.4; so drop that. This moves Makefile-linux-26
into Makefile and drops Kbuild. Also having wrappers as both Kbuild and
Makefile seemed redundant anyways.
The patch is relatively large because it renames a file, but no functional
changes.
SGI-PV: 971050
SGI-Modid: xfs-linux-melb:xfs-kern:29781a
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Donald Douwsma <donaldd@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Extract the common code to remove a dentry from the lru into a new function
dentry_lru_remove().
Two call sites used list_del() instead of list_del_init(). AFAIK the
performance of both is the same. dentry_lru_remove() does a list_del_init().
As a result dentry->d_lru is now always empty when a dentry is freed.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
d_path() is used on a <dentry,vfsmount> pair. Lets use a struct path to
reflect this.
[akpm@linux-foundation.org: fix build in mm/memory.c]
Signed-off-by: Jan Blunck <jblunck@suse.de>
Acked-by: Bryan Wu <bryan.wu@analog.com>
Acked-by: Christoph Hellwig <hch@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
seq_path() is always called with a dentry and a vfsmount from a struct path.
Make seq_path() take it directly as an argument.
Signed-off-by: Jan Blunck <jblunck@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I'm embedding struct path into struct svc_expkey.
Signed-off-by: Jan Blunck <jblunck@suse.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
get_dcookie() is always called with a dentry and a vfsmount from a struct
path. Make get_dcookie() take it directly as an argument.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Jan Blunck <jblunck@suse.de>
Acked-by: Christoph Hellwig <hch@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
proc_get_link() is always called with a dentry and a vfsmount from a struct
path. Make proc_get_link() take it directly as an argument.
Signed-off-by: Jan Blunck <jblunck@suse.de>
Acked-by: Christoph Hellwig <hch@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Neil Brown <neilb@suse.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Move and update d_path() kernel API documentation.
Signed-off-by: Jan Blunck <jblunck@suse.de>
Acked-by: Christoph Hellwig <hch@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
All callers to __d_path pass the dentry and vfsmount of a struct path to
__d_path. Pass the struct path directly, instead.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Jan Blunck <jblunck@suse.de>
Acked-by: Christoph Hellwig <hch@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In nearly all cases the set_fs_{root,pwd}() calls work on a struct
path. Change the function to reflect this and use path_get() here.
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Use struct path in fs_struct.
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Jan Blunck <jblunck@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This introduces the symmetric function to path_put() for getting a reference
to the dentry and vfsmount of a struct path in the right order.
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use path_put() in a few places instead of {mnt,d}put()
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
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>
* Add path_put() functions for releasing a reference to the dentry and
vfsmount of a struct path in the right order
* Switch from path_release(nd) to path_put(&nd->path)
* Rename dput_path() to path_put_conditional()
[akpm@linux-foundation.org: fix cifs]
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: <linux-fsdevel@vger.kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Steven French <sfrench@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the central patch of a cleanup series. In most cases there is no good
reason why someone would want to use a dentry for itself. This series reflects
that fact and embeds a struct path into nameidata.
Together with the other patches of this series
- it enforced the correct order of getting/releasing the reference count on
<dentry,vfsmount> pairs
- it prepares the VFS for stacking support since it is essential to have a
struct path in every place where the stack can be traversed
- it reduces the overall code size:
without patch series:
text data bss dec hex filename
5321639 858418 715768 6895825 6938d1 vmlinux
with patch series:
text data bss dec hex filename
5320026 858418 715768 6894212 693284 vmlinux
This patch:
Switch from nd->{dentry,mnt} to nd->path.{dentry,mnt} everywhere.
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix cifs]
[akpm@linux-foundation.org: fix smack]
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
path_release_on_umount() should only be called from sys_umount(). I merged the
function into sys_umount() instead of having in in namei.c.
Signed-off-by: Jan Blunck <jblunck@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The warning issued by fs/binfmt_flat.c when the format handler is given a
non-FLAT and non-script executable is annoying to say the least when working
with FDPIC ELF objects. If you build a kernel that supports both FLAT and
FDPIC ELFs on no-mmu, every time you execute an FDPIC ELF, the kernel spits
out this message. While I understand a lot of newcomers to the no-mmu world
screw up generation of FLAT binaries, this warning is not usable for systems
that support more than just FLAT.
Signed-off-by: Jie Zhang <jie.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: Bernd Schmidt <bernds_cb1@t-online.de>
Acked-by: Greg Ungerer <gerg@snapgear.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
inotify_max_user_instances, inotify_max_user_watches,
inotify_max_queued_events can all be made static.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The error field in nfs_readdir_descriptor_t is never used outside of the
function in which it is set. Remove the field and change the place that
does use it to use an existing local variable.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The warning message for a v4 server returning various bad sequence-ids is
missing spaces.
Signed-off-by: Dan Muntz <dmuntz@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The compat_sys_mount() system call throws EINVAL for text-based NFSv4
mounts.
The text-based mount interface assumes that any mount option blob that
doesn't set the version field to "1" is a C string (ie not a legacy
mount request). The compat_sys_mount() call treats blobs that don't
set the version field to "1" as an error. We just relax the check in
compat_sys_mount() a bit to allow C strings to be passed down to the NFSv4
client.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The reference counting for the NFSv4 callback thread stays artificially
high. When this thread comes down, it doesn't properly tear down the
svc_serv, causing a memory leak. In my testing on an older kernel on
x86_64, memory would leak out of the 8k kmalloc slab. So, we're leaking
at least a page of memory every time the thread comes down.
svc_create() creates the svc_serv with a sv_nrthreads count of 1, and
then svc_create_thread() increments that count. Whenever the callback
thread is started it has a sv_nrthreads count of 2. When coming down, it
calls svc_exit_thread() which decrements that count and if it hits 0, it
tears everything down. That never happens here since the count is always
at 2 when the thread exits.
The problem is that nfs_callback_up() should be calling svc_destroy() on
the svc_serv on both success and failure. This is how lockd_up_proto()
handles the reference counting, and doing that here fixes the leak.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
In commit 742ba02a51 (udf: create common
function for changing free space counter) by accident I reversed safety
condition which lead to null pointer dereference in case of media error and
wrong counting of free space in normal situation
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Jan Kara <jack@suse.cz>
Acked-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch cleaning up UDF directory offset handling missed modifications in dir.c
(because I've submitted an old version :(). Fix it.
Signed-off-by: Jan Kara <jack@suse.cz>
Reported-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Tested-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix the warning message regarding smbfs to
"smbfs is deprecated and will be removed from the 2.6.27 kernel. Please migrate to cifs"
instead of
"smbfs is deprecated and will be removedfrom the 2.6.27 kernel. Please migrate to cifs"
Signed-off-by: Sergio Luis <sergio@uece.br>
Screwed-up-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Steven French <sfrench@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
remove beX_add functions and replace all uses with beX_add_cpu
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Reviewed-by: Dave Chinner <dgc@sgi.com>
Cc: Timothy Shimmin <tes@sgi.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://linux-nfs.org/~bfields/linux:
SUNPRC: Fix printk format warning
nfsd: clean up svc_reserve_auth()
NLM: don't requeue block if it was invalidated while GRANT_MSG was in flight
NLM: don't reattempt GRANT_MSG when there is already an RPC in flight
NLM: have server-side RPC clients default to soft RPC tasks
NLM: set RPC_CLNT_CREATE_NOPING for NLM RPC clients
It's possible for lockd to catch a SIGKILL while a GRANT_MSG callback
is in flight. If this happens we don't want lockd to insert the block
back into the nlm_blocked list.
This helps that situation, but there's still a possible race. Fixing
that will mean adding real locking for nlm_blocked.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
With the current scheme in nlmsvc_grant_blocked, we can end up with more
than one GRANT_MSG callback for a block in flight. Right now, we requeue
the block unconditionally so that a GRANT_MSG callback is done again in
30s. If the client is unresponsive, it can take more than 30s for the
call already in flight to time out.
There's no benefit to having more than one GRANT_MSG RPC queued up at a
time, so put it on the list with a timeout of NLM_NEVER before doing the
RPC call. If the RPC call submission fails, we requeue it with a short
timeout. If it works, then nlmsvc_grant_callback will end up requeueing
it with a shorter timeout after it completes.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Now that it no longer does an RPC ping, lockd always ends up queueing
an RPC task for the GRANT_MSG callback. But, it also requeues the block
for later attempts. Since these are hard RPC tasks, if the client we're
calling back goes unresponsive the GRANT_MSG callbacks can stack up in
the RPC queue.
Fix this by making server-side RPC clients default to soft RPC tasks.
lockd requeues the block anyway, so this should be OK.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
It's currently possible for an unresponsive NLM client to completely
lock up a server's lockd. The scenario is something like this:
1) client1 (or a process on the server) takes a lock on a file
2) client2 tries to take a blocking lock on the same file and
awaits the callback
3) client2 goes unresponsive (plug pulled, network partition, etc)
4) client1 releases the lock
...at that point the server's lockd will try to queue up a GRANT_MSG
callback for client2, but first it requeues the block with a timeout of
30s. nlm_async_call will attempt to bind the RPC client to client2 and
will call rpc_ping. rpc_ping entails a sync RPC call and if client2 is
unresponsive it will take around 60s for that to time out. Once it times
out, it's already time to retry the block and the whole process repeats.
Once in this situation, nlmsvc_retry_blocked will never return until
the host starts responding again. lockd won't service new calls.
Fix this by skipping the RPC ping on NLM RPC clients. This makes
nlm_async_call return quickly when called.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Commit 8811930dc7 ("splice: missing user
pointer access verification") added the proper access_ok() calls to
copy_from_user_mmap_sem() which ensures we can copy the struct iovecs
from userspace to the kernel.
But we also must check whether we can access the actual memory region
pointed to by the struct iovec to fix the access checks properly.
Signed-off-by: Bastian Blank <waldi@debian.org>
Acked-by: Oliver Pinter <oliver.pntr@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This flag is simply a generic "this is a crash/burn test filesystem"
marker. If it is set, then filesystem code which is "in development"
will be allowed to mount the filesystem. Filesystem code which is not
considered ready for prime-time will check for this flag, and if it is
not set, it will refuse to touch the filesystem.
As we start rolling ext4 out to distro's like Fedora, et. al, this makes
it less likely that a user might accidentally start using ext4 on a
production filesystem; a bad thing, since that will essentially make it
be unfsckable until e2fsprogs catches up.
Signed-off-by: Theodore Tso <tytso@MIT.EDU>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Multiblock allocator calls BUG_ON in many case if the free and used
blocks count obtained looking at the bitmap is different from what
the allocator internally accounted for. Use ext4_error in such case
and don't panic the system.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
struct ext4_allocation_context is rather large, and this bloats
the stack of many functions which use it. Allocating it from
a named slab cache will alleviate this.
For example, with this change (on top of the noinline patch sent earlier):
-ext4_mb_new_blocks 200
+ext4_mb_new_blocks 40
-ext4_mb_free_blocks 344
+ext4_mb_free_blocks 168
-ext4_mb_release_inode_pa 216
+ext4_mb_release_inode_pa 40
-ext4_mb_release_group_pa 192
+ext4_mb_release_group_pa 24
Most of these stack-allocated structs are actually used only for
mballoc history; and in those cases often a smaller struct would do.
So changing that may be another way around it, at least for those
functions, if preferred. For now, in those cases where the ac
is only for history, an allocation failure simply skips the history
recording, and does not cause any other failures.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
In JBD2 jbd2_journal_write_commit_record(), clear the buffer_ordered
flag for the bh after barried IO has succeed. This prevents later, if
the same buffer head were submitted to the underlying device, which has
been reconfigured to not support barrier request, the JBD2 commit code
could treat it as a normal IO (without barrier).
This is a port from JBD/ext3 fix from Neil Brown.
More details from Neil:
Some devices - notably dm and md - can change their behaviour in
response to BIO_RW_BARRIER requests. They might start out accepting
such requests but on reconfiguration, they find out that they cannot
any more. JBD2 deal with this by always testing if BIO_RW_BARRIER
requests fail with EOPNOTSUPP, and retrying the write
requests without the barrier (probably after waiting for any pending
writes to complete).
However there is a bug in the handling this in JBD2 for ext4 .
When ext4/JBD2 to submit a BIO_RW_BARRIER request,
it sets the buffer_ordered flag on the buffer head.
If the request completes successfully, the flag STAYS SET.
Other code might then write the same buffer_head after the device has
been reconfigured to not accept barriers. This write will then fail,
but the "other code" is not ready to handle EOPNOTSUPP errors and the
error will be treated as fatal.
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
We cannot start transaction in ext4_direct_IO() and just let it last
during the whole write because dio_get_page() acquires mmap_sem which
ranks above transaction start (e.g. because we have dependency chain
mmap_sem->PageLock->journal_start, or because we update atime while
holding mmap_sem) and thus deadlocks could happen. We solve the problem
by starting a transaction separately for each ext4_get_block() call.
We *could* have a problem that we allocate a block and before its data
are written out the machine crashes and thus we expose stale data. But
that does not happen because for hole-filling generic code falls back to
buffered writes and for file extension, we add inode to orphan list and
thus in case of crash, journal replay will truncate inode back to the
original size.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
In order to prevent a circular locking dependency when an unlink
operation is racing with an ext4 migration, we delay taking i_data_sem
until just before switch the inode format, and use i_mutex to prevent
writes and truncates during the first part of the migration operation.
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
When xfs_file_readdir() exactly fills a buffer, it can move it's index
past the end of the buffer and dereference it even though the result of
the dereference is never used. On some platforms this causes an oops.
SGI-PV: 976923
SGI-Modid: xfs-linux-melb:xfs-kern:30458a
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Jeff Layton