In order to open code and expose the result pointer assignment.
Alternatively, we can open code the call to xdr_reserve_space
and do the BUG_ON an the error case at the call site.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This is already done by xdr_reserve_space and since encode_compound_hdr
is adding a byte count to "12" which is already word aligned, the xdr
level rounding will work just as well.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Although this file is only ever written and not read by
userspace, it seems that the utils are opening this
file O_RDWR, so we need to allow that.
Also fixes the whitespace which seemed to be broken.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: David Teigland <teigland@redhat.com>
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2: (22 commits)
ocfs2: Fix possible deadlock when extending quota file
ocfs2: keep index within status_map[]
ocfs2: Initialize the cluster we're writing to in a non-sparse extend
ocfs2: Remove redundant BUG_ON in __dlm_queue_ast()
ocfs2/quota: Release lock for error in ocfs2_quota_write.
ocfs2: Define credit counts for quota operations
ocfs2: Remove syncjiff field from quota info
ocfs2: Fix initialization of blockcheck stats
ocfs2: Zero out padding of on disk dquot structure
ocfs2: Initialize blocks allocated to local quota file
ocfs2: Mark buffer uptodate before calling ocfs2_journal_access_dq()
ocfs2: Make global quota files blocksize aligned
ocfs2: Use ocfs2_rec_clusters in ocfs2_adjust_adjacent_records.
ocfs2: Fix deadlock on umount
ocfs2: Add extra credits and access the modified bh in update_edge_lengths.
ocfs2: Fail ocfs2_get_block() immediately when a block needs allocation
ocfs2: Fix error return in ocfs2_write_cluster()
ocfs2: Fix compilation warning for fs/ocfs2/xattr.c
ocfs2: Initialize count in aio_write before generic_write_checks
ocfs2: log the actual return value of ocfs2_file_aio_write()
...
* 'for-linus' of git://oss.sgi.com/xfs/xfs:
xfs: fix spin_is_locked assert on uni-processor builds
xfs: check for dinode realtime flag corruption
use XFS_CORRUPTION_ERROR in xfs_btree_check_sblock
xfs: switch to NOFS allocation under i_lock in xfs_attr_rmtval_get
xfs: switch to NOFS allocation under i_lock in xfs_readlink_bmap
xfs: switch to NOFS allocation under i_lock in xfs_attr_rmtval_set
xfs: switch to NOFS allocation under i_lock in xfs_buf_associate_memory
xfs: switch to NOFS allocation under i_lock in xfs_dir_cilookup_result
xfs: switch to NOFS allocation under i_lock in xfs_da_buf_make
xfs: switch to NOFS allocation under i_lock in xfs_da_state_alloc
xfs: switch to NOFS allocation under i_lock in xfs_getbmap
xfs: avoid memory allocation under m_peraglock in growfs code
We can't call nfs_readdata_release()/nfs_writedata_release() without
first initialising and referencing args.context. Doing so inside
nfs_direct_read_schedule_segment()/nfs_direct_write_schedule_segment()
causes an Oops.
We should rather be calling nfs_readdata_free()/nfs_writedata_free() in
those cases.
Looking at the O_DIRECT code, the "struct nfs_direct_req" is already
referencing the nfs_open_context for us. Since the readdata and writedata
structures carry a reference to that, we can simplify things by getting rid
of the extra nfs_open_context references, so that we can replace all
instances of nfs_readdata_release()/nfs_writedata_release().
Reported-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Without SMP or preemption spin_is_locked always returns false,
so we can't do an assert with it. Instead use assert_spin_locked,
which does the right thing on all builds.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
Reported-by: Johannes Engel <jcnengel@googlemail.com>
Tested-by: Johannes Engel <jcnengel@googlemail.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
Ramon tested XFS with a modified version of fsfuzzer and hit a NULL
pointer dereference in __xfs_get_blocks due to the RT device target
pointer being NULL.
To fix this reject inode with the realtime bit set on a a filesystem
without an RT subvolume during inode read.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Reported-by: Ramon de Carvalho Valle <ramon@risesecurity.org>
Tested-by: Ramon de Carvalho Valle <ramon@risesecurity.org>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
In Red Hat Bug 512552
- Can't write to XFS mount during raid5 resync
a user ran into corruption while resyncing a raid, and we failed
a consistency test, but didn't get much more info; it'd be nice
to call XFS_CORRUPTION_ERROR here so we can see the buffer
contents.
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
xfs_attr_rmtval_get is always called with i_lock held, but i_lock is taken
in reclaim context so all allocations under it must avoid recursions into
the filesystem.
Reported by the new reclaim context tracing in lockdep.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
xfs_readlink_bmap is called with i_lock held, but i_lock is taken in
reclaim context so all allocations under it must avoid recursions into
the filesystem.
Reported by the new reclaim context tracing in lockdep.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
xfs_attr_rmtval_set is always called with i_lock held, and i_lock is taken
in reclaim context so all allocations under it must avoid recursions into
the filesystem.
Reported by the new reclaim context tracing in lockdep.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
xfs_buf_associate_memory is used for setting up the spare buffer for the
log wrap case in xlog_sync which can happen under i_lock when called from
xfs_fsync. The i_lock mutex is taken in reclaim context so all allocations
under it must avoid recursions into the filesystem. There are a couple
more uses of xfs_buf_associate_memory in the log recovery code that are
also affected by this, but I'd rather keep the code simple than passing on
a gfp_mask argument. Longer term we should just stop requiring the memoery
allocation in xlog_sync by some smaller rework of the buffer layer.
Reported by the new reclaim context tracing in lockdep.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
xfs_dir_cilookup_result is always called with i_lock held, but i_lock is taken
in reclaim context so all allocations under it must avoid recursions into the
filesystem.
Reported by the new reclaim context tracing in lockdep.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
i_lock is taken in the reclaim context so all allocations under it
must avoid recursions into the filesystem.
Reported by the new reclaim context tracing in lockdep.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
xfs_da_state_alloc is always called with i_lock held, but i_lock is taken in
reclaim context so all allocations under it must avoid recursions into the
filesystem.
Reported by the new reclaim context tracing in lockdep.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
xfs_getbmap allocates memory with i_lock held, but i_lock is taken in
reclaim context so all allocations under it must avoid recursions into
the filesystem.
Reported by the new reclaim context tracing in lockdep.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
Allocate the memory for the larger m_perag array before taking the
per-AG lock as the per-AG lock can be taken under the i_lock which
can be taken from reclaim context.
Reported by the new reclaim context tracing in lockdep.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
In OCFS2, allocator locks rank above transaction start. Thus we
cannot extend quota file from inside a transaction less we could
deadlock.
We solve the problem by starting transaction not already in
ocfs2_acquire_dquot() but only in ocfs2_local_read_dquot() and
ocfs2_global_read_dquot() and we allocate blocks to quota files before starting
the transaction. In case we crash, quota files will just have a few blocks
more but that's no problem since we just use them next time we extend the
quota file.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
Subject: [PATCH] nfs: remove superfluous BUG_ON()s
Remove duplicated BUG_ON()s from nfs[4]_create_server()
(we make the same checks earlier in both functions).
This takes care of the following entries from Dan's list:
fs/nfs/client.c +1078 nfs_create_server(47) warning: variable derefenced before check 'server->nfs_client'
fs/nfs/client.c +1079 nfs_create_server(48) warning: variable derefenced before check 'server->nfs_client->rpc_ops'
fs/nfs/client.c +1363 nfs4_create_server(43) warning: variable derefenced before check 'server->nfs_client'
fs/nfs/client.c +1364 nfs4_create_server(44) warning: variable derefenced before check 'server->nfs_
Reported-by: Dan Carpenter <error27@gmail.com>
Cc: corbet@lwn.net
Cc: eteo@redhat.com
Cc: Julia Lawall <julia@diku.dk>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Hi.
I have a proposal for possibly resolving this issue.
I believe that this situation occurs due to the way that the
Linux NFS client handles writes which modify partial pages.
The Linux NFS client handles partial page modifications by
allocating a page from the page cache, copying the data from
the user level into the page, and then keeping track of the
offset and length of the modified portions of the page. The
page is not marked as up to date because there are portions
of the page which do not contain valid file contents.
When a read call comes in for a portion of the page, the
contents of the page must be read in the from the server.
However, since the page may already contain some modified
data, that modified data must be written to the server
before the file contents can be read back in the from server.
And, since the writing and reading can not be done atomically,
the data must be written and committed to stable storage on
the server for safety purposes. This means either a
FILE_SYNC WRITE or a UNSTABLE WRITE followed by a COMMIT.
This has been discussed at length previously.
This algorithm could be described as modify-write-read. It
is most efficient when the application only updates pages
and does not read them.
My proposed solution is to add a heuristic to decide whether
to do this modify-write-read algorithm or switch to a read-
modify-write algorithm when initially allocating the page
in the write system call path. The heuristic uses the modes
that the file was opened with, the offset in the page to
read from, and the size of the region to read.
If the file was opened for reading in addition to writing
and the page would not be filled completely with data from
the user level, then read in the old contents of the page
and mark it as Uptodate before copying in the new data. If
the page would be completely filled with data from the user
level, then there would be no reason to read in the old
contents because they would just be copied over.
This would optimize for applications which randomly access
and update portions of files. The linkage editor for the
C compiler is an example of such a thing.
I tested the attached patch by using rpmbuild to build the
current Fedora rawhide kernel. The kernel without the
patch generated about 269,500 WRITE requests. The modified
kernel containing the patch generated about 261,000 WRITE
requests. Thus, about 8,500 fewer WRITE requests were
generated. I suspect that many of these additional
WRITE requests were probably FILE_SYNC requests to WRITE
a single page, but I didn't test this theory.
The difference between this patch and the previous one was
to remove the unneeded PageDirty() test. I then retested to
ensure that the resulting system continued to behave as
desired.
Thanx...
ps
Signed-off-by: Peter Staubach <staubach@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
[un]register_chrdev() assume minor range 0-255. This patch adds __
prefixed versions which take @minorbase and @count explicitly.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The problem is minor, but without ->cred_guard_mutex held we can race
with exec() and get the new ->mm but check old creds.
Now we do not need to re-check task->mm after ptrace_may_access(), it
can't be changed to the new mm under us.
Strictly speaking, this also fixes another very minor problem. Unless
security check fails or the task exits mm_for_maps() should never
return NULL, the caller should get either old or new ->mm.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
mm_for_maps() takes ->mmap_sem after security checks, this looks
strange and obfuscates the locking rules. Move this lock to its
single caller, m_start().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
It would be nice to kill __ptrace_may_access(). It requires task_lock(),
but this lock is only needed to read mm->flags in the middle.
Convert mm_for_maps() to use ptrace_may_access(), this also simplifies
the code a little bit.
Also, we do not need to take ->mmap_sem in advance. In fact I think
mm_for_maps() should not play with ->mmap_sem at all, the caller should
take this lock.
With or without this patch, without ->cred_guard_mutex held we can race
with exec() and get the new ->mm but check old creds.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
The problem is minor, but without ->cred_guard_mutex held we can race
with exec() and get the new ->mm but check old creds.
Now we do not need to re-check task->mm after ptrace_may_access(), it
can't be changed to the new mm under us.
Strictly speaking, this also fixes another very minor problem. Unless
security check fails or the task exits mm_for_maps() should never
return NULL, the caller should get either old or new ->mm.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
mm_for_maps() takes ->mmap_sem after security checks, this looks
strange and obfuscates the locking rules. Move this lock to its
single caller, m_start().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
For events that are rare, such as referral DNS lookups, it makes limited
sense to have a daemon constantly listening for upcalls on a channel. An
alternative in those cases might simply be to run the app that fills the
cache using call_usermodehelper_exec() and friends.
The following patch allows the cache_detail to specify alternative upcall
mechanisms for these particular cases.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
In write_failover_ip(), replace the sscanf() with a call to the common
sunrpc.ko presentation address parser.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: Use shared rpc_set_port() function instead of nlm_clear_port().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: Use the common routine now provided in sunrpc.ko for parsing mount
addresses.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Introduce a set of functions in the kernel's RPC implementation for
converting between a socket address and either a standard
presentation address string or an RPC universal address.
The universal address functions will be used to encode and decode
RPCB_FOO and NFSv4 SETCLIENTID arguments. The other functions are
part of a previous promise to deliver shared functions that can be
used by upper-layer protocols to display and manipulate IP
addresses.
The kernel's current address printf formatters were designed
specifically for kernel to user-space APIs that require a particular
string format for socket addresses, thus are somewhat limited for the
purposes of sunrpc.ko. The formatter for IPv6 addresses, %pI6, does
not support short-handing or scope IDs. Also, these printf formatters
are unique per address family, so a separate formatter string is
required for printing AF_INET and AF_INET6 addresses.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Commit a14017db added support in the kernel's NFS mount client to
decode the authentication flavor list returned by mountd.
The NFS client can now use this list to determine whether the
authentication flavor requested by the user is actually supported
by the server.
Note we don't actually negotiate the security flavor if none was
specified by the user. Instead, we try to use AUTH_SYS, and fail if
the server does not support it. This prevents us from negotiating
an inappropriate security flavor (some servers list AUTH_NULL first).
If the server does not support AUTH_SYS, the user must provide an
appropriate security flavor by specifying the "sec=" mount option.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Previous logic in the NFS mount parsing code path assumed
auth_flavor_len was set to zero for simple authentication flavors
(like AUTH_UNIX), and 1 for compound flavors (like AUTH_GSS).
At some earlier point (maybe even before the option parsers were
merged?) specific checks for auth_flavor_len being zero were removed
from the functions that validate the mount option that sets the mount
point's authentication flavor.
Since we are populating an array for authentication flavors, the
auth_flavor_len should always be set to the number of flavors. Let's
eliminate some cleverness here, and prepare for new logic that needs
to know the number of flavors in the auth_flavors[] array.
(auth_flavors[] is an array because at some point we want to allow a
list of acceptable authentication flavors to be specified via the sec=
mount option. For now it remains a single element array).
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
After certain failure modes of an NFS mount, an NFS client should send
a MOUNTPROC_UMNT request to remove the just-added mount entry from the
server's mount table. While no-one should rely on the accuracy of the
server's mount table, sending a UMNT is simply being a good internet
neighbor.
Since NFS mount processing is handled in the kernel now, we will need
a function in the kernel's mountd client that can post a MOUNTRPC_UMNT
request, in order to handle these failure modes.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The new minorversion= mount option (commit 3fd5be9e) was merged at
the same time as the recent sloppy parser fixes (commit a5a16bae),
so minorversion= still uses the old value parsing logic.
If the minorversion= option specifies a bogus value, it should fail
with "bad value" not "bad option."
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
