Pull vfs documentation typo fix from Al Viro.
* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
typo fix: it's d_make_root, not d_make_inode...
Clearify d_make_root() usage, error handling and cleanup
requirements.
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
A recent documentation conversion renamed this file but forgot
to update the links.
Fixes: af96c1e304 ("docs: filesystems: vfs: Convert vfs.txt to RST")
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Pull misc dcache updates from Al Viro:
"Most of this pile is putting name length into struct name_snapshot and
making use of it.
The beginning of this series ("ovl_lookup_real_one(): don't bother
with strlen()") ought to have been split in two (separate switch of
name_snapshot to struct qstr from overlayfs reaping the trivial
benefits of that), but I wanted to avoid a rebase - by the time I'd
spotted that it was (a) in -next and (b) close to 5.1-final ;-/"
* 'work.dcache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
audit_compare_dname_path(): switch to const struct qstr *
audit_update_watch(): switch to const struct qstr *
inotify_handle_event(): don't bother with strlen()
fsnotify: switch send_to_group() and ->handle_event to const struct qstr *
fsnotify(): switch to passing const struct qstr * for file_name
switch fsnotify_move() to passing const struct qstr * for old_name
ovl_lookup_real_one(): don't bother with strlen()
sysv: bury the broken "quietly truncate the long filenames" logics
nsfs: unobfuscate
unexport d_alloc_pseudo()
Pull vfs stable fodder fixes from Al Viro:
- acct_on() fix for deadlock caught by overlayfs folks
- autofs RCU use-after-free SNAFU (->d_manage() can be called
locklessly, so we need to RCU-delay freeing the objects it looks at)
- (hopefully) the end of "do we need freeing this dentry RCU-delayed"
whack-a-mole.
* 'stable-fodder' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
autofs: fix use-after-free in lockless ->d_manage()
dcache: sort the freeing-without-RCU-delay mess for good.
acct_on(): don't mess with freeze protection
A lot of ->destroy_inode() instances end with call_rcu() of a callback
that does RCU-delayed part of freeing. Introduce a new method for
doing just that, with saner signature.
Rules:
->destroy_inode ->free_inode
f g immediate call of f(),
RCU-delayed call of g()
f NULL immediate call of f(),
no RCU-delayed calls
NULL g RCU-delayed call of g()
NULL NULL RCU-delayed default freeing
IOW, NULL ->free_inode gives the same behaviour as now.
Note that NULL, NULL is equivalent to NULL, free_inode_nonrcu; we could
mandate the latter form, but that would have very little benefit beyond
making rules a bit more symmetric. It would break backwards compatibility,
require extra boilerplate and expected semantics for (NULL, NULL) pair
would have no use whatsoever...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
No modular uses since introducion of alloc_file_pseudo(),
and the only non-modular user not in alloc_file_pseudo()
had actually been wrong - should've been d_alloc_anon().
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
For lockless accesses to dentries we don't have pinned we rely
(among other things) upon having an RCU delay between dropping
the last reference and actually freeing the memory.
On the other hand, for things like pipes and sockets we neither
do that kind of lockless access, nor want to deal with the
overhead of an RCU delay every time a socket gets closed.
So delay was made optional - setting DCACHE_RCUACCESS in ->d_flags
made sure it would happen. We tried to avoid setting it unless
we knew we need it. Unfortunately, that had led to recurring
class of bugs, in which we missed the need to set it.
We only really need it for dentries that are created by
d_alloc_pseudo(), so let's not bother with trying to be smart -
just make having an RCU delay the default. The ones that do
*not* get it set the replacement flag (DCACHE_NORCU) and we'd
better use that sparingly. d_alloc_pseudo() is the only
such user right now.
FWIW, the race that finally prompted that switch had been
between __lock_parent() of immediate subdirectory of what's
currently the root of a disconnected tree (e.g. from
open-by-handle in progress) racing with d_splice_alias()
elsewhere picking another alias for the same inode, either
on outright corrupted fs image, or (in case of open-by-handle
on NFS) that subdirectory having been just moved on server.
It's not easy to hit, so the sky is not falling, but that's
not the first race on similar missed cases and the logics
for settinf DCACHE_RCUACCESS has gotten ridiculously
convoluted.
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Rework the vfs_clone_file_range and vfs_dedupe_file_range infrastructure to use
a common .remap_file_range method and supply generic bounds and sanity checking
functions that are shared with the data write path. The current VFS
infrastructure has problems with rlimit, LFS file sizes, file time stamps,
maximum filesystem file sizes, stripping setuid bits, etc and so they are
addressed in these commits.
We also introduce the ability for the ->remap_file_range methods to return short
clones so that clones for vfs_copy_file_range() don't get rejected if the entire
range can't be cloned. It also allows filesystems to sliently skip deduplication
of partial EOF blocks if they are not capable of doing so without requiring
errors to be thrown to userspace.
All existing filesystems are converted to user the new .remap_file_range method,
and both XFS and ocfs2 are modified to make use of the new generic checking
infrastructure.
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Merge tag 'xfs-4.20-merge-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull vfs dedup fixes from Dave Chinner:
"This reworks the vfs data cloning infrastructure.
We discovered many issues with these interfaces late in the 4.19 cycle
- the worst of them (data corruption, setuid stripping) were fixed for
XFS in 4.19-rc8, but a larger rework of the infrastructure fixing all
the problems was needed. That rework is the contents of this pull
request.
Rework the vfs_clone_file_range and vfs_dedupe_file_range
infrastructure to use a common .remap_file_range method and supply
generic bounds and sanity checking functions that are shared with the
data write path. The current VFS infrastructure has problems with
rlimit, LFS file sizes, file time stamps, maximum filesystem file
sizes, stripping setuid bits, etc and so they are addressed in these
commits.
We also introduce the ability for the ->remap_file_range methods to
return short clones so that clones for vfs_copy_file_range() don't get
rejected if the entire range can't be cloned. It also allows
filesystems to sliently skip deduplication of partial EOF blocks if
they are not capable of doing so without requiring errors to be thrown
to userspace.
Existing filesystems are converted to user the new remap_file_range
method, and both XFS and ocfs2 are modified to make use of the new
generic checking infrastructure"
* tag 'xfs-4.20-merge-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (28 commits)
xfs: remove [cm]time update from reflink calls
xfs: remove xfs_reflink_remap_range
xfs: remove redundant remap partial EOF block checks
xfs: support returning partial reflink results
xfs: clean up xfs_reflink_remap_blocks call site
xfs: fix pagecache truncation prior to reflink
ocfs2: remove ocfs2_reflink_remap_range
ocfs2: support partial clone range and dedupe range
ocfs2: fix pagecache truncation prior to reflink
ocfs2: truncate page cache for clone destination file before remapping
vfs: clean up generic_remap_file_range_prep return value
vfs: hide file range comparison function
vfs: enable remap callers that can handle short operations
vfs: plumb remap flags through the vfs dedupe functions
vfs: plumb remap flags through the vfs clone functions
vfs: make remap_file_range functions take and return bytes completed
vfs: remap helper should update destination inode metadata
vfs: pass remap flags to generic_remap_checks
vfs: pass remap flags to generic_remap_file_range_prep
vfs: combine the clone and dedupe into a single remap_file_range
...
Combine the clone_file_range and dedupe_file_range operations into a
single remap_file_range file operation dispatch since they're
fundamentally the same operation. The differences between the two can
be made in the prep functions.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Short version: it does the right thing when given NULL or ERR_PTR(...)
and its calling conventions are chosen to have minimal PITA when
used in ->lookup() instances.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Explicit locking in the fallback case provides a safe state of the
table. Getting rid of blocking semantics makes __fd_install usable
again in non-sleepable contexts, which easies backporting efforts.
There is a side effect of slightly nicer assembly for the common case
as might_sleep can now be removed.
Signed-off-by: Mateusz Guzik <mguzik@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Differentiate the MS_* flags passed to mount(2) from the internal flags set
in the super_block's s_flags. s_flags are now called SB_*, with the names
and the values for the moment mirroring the MS_* flags that they're
equivalent to.
In this patch, just the headers are altered and some kernel code where
blind automated conversion isn't necessarily correct.
Note that this shows up some interesting issues:
(1) Some MS_* flags get translated to MNT_* flags (such as MS_NODEV ->
MNT_NODEV) without passing this on to the filesystem, but some
filesystems set such flags anyway.
(2) The ->remount_fs() methods of some filesystems adjust the *flags
argument by setting MS_* flags in it, such as MS_NOATIME - but these
flags are then scrubbed by do_remount_sb() (only the occupants of
MS_RMT_MASK are permitted: MS_RDONLY, MS_SYNCHRONOUS, MS_MANDLOCK,
MS_I_VERSION and MS_LAZYTIME)
I'm not sure what's the best way to solve all these cases.
Suggested-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Following the recent merge of statx, correct the documented prototype
for the ->getattr() inode operation, and add an entry to the porting
file.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
If i_op->readlink is NULL, but i_op->get_link is set then vfs_readlink()
defaults to calling generic_readlink().
The IOP_DEFAULT_READLINK flag indicates that the above conditions are met
and the default action can be taken.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Pull more vfs updates from Al Viro:
">rename2() work from Miklos + current_time() from Deepa"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
fs: Replace current_fs_time() with current_time()
fs: Replace CURRENT_TIME_SEC with current_time() for inode timestamps
fs: Replace CURRENT_TIME with current_time() for inode timestamps
fs: proc: Delete inode time initializations in proc_alloc_inode()
vfs: Add current_time() api
vfs: add note about i_op->rename changes to porting
fs: rename "rename2" i_op to "rename"
vfs: remove unused i_op->rename
fs: make remaining filesystems use .rename2
libfs: support RENAME_NOREPLACE in simple_rename()
fs: support RENAME_NOREPLACE for local filesystems
ncpfs: fix unused variable warning
inode_change_ok() will be resposible for clearing capabilities and IMA
extended attributes and as such will need dentry. Give it as an argument
to inode_change_ok() instead of an inode. Also rename inode_change_ok()
to setattr_prepare() to better relect that it does also some
modifications in addition to checks.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
smack ->d_instantiate() uses ->setxattr(), so to be able to call it before
we'd hashed the new dentry and attached it to inode, we need ->setxattr()
instances getting the inode as an explicit argument rather than obtaining
it from dentry.
Similar change for ->getxattr() had been done in commit ce23e64. Unlike
->getxattr() (which is used by both selinux and smack instances of
->d_instantiate()) ->setxattr() is used only by smack one and unfortunately
it got missed back then.
Reported-by: Seung-Woo Kim <sw0312.kim@samsung.com>
Tested-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
New method: ->iterate_shared(). Same arguments as in ->iterate(),
called with the directory locked only shared. Once all filesystems
switch, the old one will be gone.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
ta-da!
The main issue is the lack of down_write_killable(), so the places
like readdir.c switched to plain inode_lock(); once killable
variants of rwsem primitives appear, that'll be dealt with.
lockdep side also might need more work
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
We'll need to verify that there's neither a hashed nor in-lookup
dentry with desired parent/name before adding to in-lookup set.
One possible solution would be to hold the parent's ->d_lock through
both checks, but while the in-lookup set is relatively small at any
time, dcache is not. And holding the parent's ->d_lock through
something like __d_lookup_rcu() would suck too badly.
So we leave the parent's ->d_lock alone, which means that we watch
out for the following scenario:
* we verify that there's no hashed match
* existing in-lookup match gets hashed by another process
* we verify that there's no in-lookup matches and decide
that everything's fine.
Solution: per-directory kinda-sorta seqlock, bumped around the times
we hash something that used to be in-lookup or move (and hash)
something in place of in-lookup. Then the above would turn into
* read the counter
* do dcache lookup
* if no matches found, check for in-lookup matches
* if there had been none of those either, check if the
counter has changed; repeat if it has.
The "kinda-sorta" part is due to the fact that we don't have much spare
space in inode. There is a spare word (shared with i_bdev/i_cdev/i_pipe),
so the counter part is not a problem, but spinlock is a different story.
We could use the parent's ->d_lock, and it would be less painful in
terms of contention, for __d_add() it would be rather inconvenient to
grab; we could do that (using lock_parent()), but...
Fortunately, we can get serialization on the counter itself, and it
might be a good idea in general; we can use cmpxchg() in a loop to
get from even to odd and smp_store_release() from odd to even.
This commit adds the counter and updating logics; the readers will be
added in the next commit.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
inode_nohighmem() is sufficient to make sure that page_get_link()
won't try to allocate a highmem page. Moreover, it is sufficient
to make sure that page_symlink/__page_symlink won't do the same
thing. However, any filesystem that manually preseeds the symlink's
page cache upon symlink(2) needs to make sure that the page it
inserts there won't be a highmem one.
Fortunately, only nfs and shmem have run afoul of that...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
new method: ->get_link(); replacement of ->follow_link(). The differences
are:
* inode and dentry are passed separately
* might be called both in RCU and non-RCU mode;
the former is indicated by passing it a NULL dentry.
* when called that way it isn't allowed to block
and should return ERR_PTR(-ECHILD) if it needs to be called
in non-RCU mode.
It's a flagday change - the old method is gone, all in-tree instances
converted. Conversion isn't hard; said that, so far very few instances
do not immediately bail out when called in RCU mode. That'll change
in the next commits.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
kmap() in page_follow_link_light() needed to go - allowing to hold
an arbitrary number of kmaps for long is a great way to deadlocking
the system.
new helper (inode_nohighmem(inode)) needs to be used for pagecache
symlinks inodes; done for all in-tree cases. page_follow_link_light()
instrumented to yell about anything missed.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull more vfs updates from Al Viro:
"Assorted VFS fixes and related cleanups (IMO the most interesting in
that part are f_path-related things and Eric's descriptor-related
stuff). UFS regression fixes (it got broken last cycle). 9P fixes.
fs-cache series, DAX patches, Jan's file_remove_suid() work"
[ I'd say this is much more than "fixes and related cleanups". The
file_table locking rule change by Eric Dumazet is a rather big and
fundamental update even if the patch isn't huge. - Linus ]
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (49 commits)
9p: cope with bogus responses from server in p9_client_{read,write}
p9_client_write(): avoid double p9_free_req()
9p: forgetting to cancel request on interrupted zero-copy RPC
dax: bdev_direct_access() may sleep
block: Add support for DAX reads/writes to block devices
dax: Use copy_from_iter_nocache
dax: Add block size note to documentation
fs/file.c: __fget() and dup2() atomicity rules
fs/file.c: don't acquire files->file_lock in fd_install()
fs:super:get_anon_bdev: fix race condition could cause dev exceed its upper limitation
vfs: avoid creation of inode number 0 in get_next_ino
namei: make set_root_rcu() return void
make simple_positive() public
ufs: use dir_pages instead of ufs_dir_pages()
pagemap.h: move dir_pages() over there
remove the pointless include of lglock.h
fs: cleanup slight list_entry abuse
xfs: Correctly lock inode when removing suid and file capabilities
fs: Call security_ops->inode_killpriv on truncate
fs: Provide function telling whether file_remove_privs() will do anything
...
Mateusz Guzik reported :
Currently obtaining a new file descriptor results in locking fdtable
twice - once in order to reserve a slot and second time to fill it.
Holding the spinlock in __fd_install() is needed in case a resize is
done, or to prevent a resize.
Mateusz provided an RFC patch and a micro benchmark :
http://people.redhat.com/~mguzik/pipebench.c
A resize is an unlikely operation in a process lifetime,
as table size is at least doubled at every resize.
We can use RCU instead of the spinlock.
__fd_install() must wait if a resize is in progress.
The resize must block new __fd_install() callers from starting,
and wait that ongoing install are finished (synchronize_sched())
resize should be attempted by a single thread to not waste resources.
rcu_sched variant is used, as __fd_install() and expand_fdtable() run
from process context.
It gives us a ~30% speedup using pipebench on a dual Intel(R) Xeon(R)
CPU E5-2696 v2 @ 2.50GHz
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Mateusz Guzik <mguzik@redhat.com>
Acked-by: Mateusz Guzik <mguzik@redhat.com>
Tested-by: Mateusz Guzik <mguzik@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The main thing here is Ingo's big subdirectory documenting feature support
for each architecture. Beyond that, it's the usual pile of fixes, tweaks,
and small additions.
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Merge tag 'docs-for-linus' of git://git.lwn.net/linux-2.6
Pull documentation updates from Jonathan Corbet:
"The main thing here is Ingo's big subdirectory documenting feature
support for each architecture. Beyond that, it's the usual pile of
fixes, tweaks, and small additions"
* tag 'docs-for-linus' of git://git.lwn.net/linux-2.6: (79 commits)
doc:md: fix typo in md.txt.
Documentation/mic/mpssd: don't build x86 userspace when cross compiling
Documentation/prctl: don't build tsc tests when cross compiling
Documentation/vDSO: don't build tests when cross compiling
Doc:ABI/testing: Fix typo in sysfs-bus-fcoe
Doc: Docbook: Change wikipedia's URL from http to https in scsi.tmpl
Doc: Change wikipedia's URL from http to https
Documentation/kernel-parameters: add missing pciserial to the earlyprintk
Doc:pps: Fix typo in pps.txt
kbuild : Fix documentation of INSTALL_HDR_PATH
Documentation: filesystems: updated struct file_operations documentation in vfs.txt
kbuild: edit explanation of clean-files variable
Doc: ja_JP: Fix typo in HOWTO
Move freefall program from Documentation/ to tools/
Documentation: ARM: EXYNOS: Describe boot loaders interface
Doc:nfc: Fix typo in nfc-hci.txt
vfs: Minor documentation fix
Doc: networking: txtimestamp: fix printf format warning
Documentation, intel_pstate: Improve legacy mode internal governors description
Documentation: extend use case for EXPORT_SYMBOL_GPL()
...
The check_acl inode operation and the IPERM_FLAG_RCU flag are long gone; update
the documentation.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
All places outside of core VFS that checked ->read and ->write for being NULL or
called the methods directly are gone now, so NULL {read,write} with non-NULL
{read,write}_iter will do the right thing in all cases.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Reclaim will be leaving shadow entries in the page cache radix tree upon
evicting the real page. As those pages are found from the LRU, an
iput() can lead to the inode being freed concurrently. At this point,
reclaim must no longer install shadow pages because the inode freeing
code needs to ensure the page tree is really empty.
Add an address_space flag, AS_EXITING, that the inode freeing code sets
under the tree lock before doing the final truncate. Reclaim will check
for this flag before installing shadow pages.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Bob Liu <bob.liu@oracle.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Luigi Semenzato <semenzato@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Metin Doslu <metin@citusdata.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Ozgun Erdogan <ozgun@citusdata.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Roman Gushchin <klamm@yandex-team.ru>
Cc: Ryan Mallon <rmallon@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For a long time no filesystem has been using vfs_follow_link, and as seen
by recent filesystem submissions any new use is accidental as well.
Remove vfs_follow_link, document the replacement in
Documentation/filesystems/porting and also rename __vfs_follow_link
to match its only caller better.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
iterate_dir(): new helper, replacing vfs_readdir().
struct dir_context: contains the readdir callback (and will get more stuff
in it), embedded into whatever data that callback wants to deal with;
eventually, we'll be passing it to ->readdir() replacement instead of
(data,filldir) pair.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The following set of operations on a NFS client and server will cause
server# mkdir a
client# cd a
server# mv a a.bak
client# sleep 30 # (or whatever the dir attrcache timeout is)
client# stat .
stat: cannot stat `.': Stale NFS file handle
Obviously, we should not be getting an ESTALE error back there since the
inode still exists on the server. The problem is that the lookup code
will call d_revalidate on the dentry that "." refers to, because NFS has
FS_REVAL_DOT set.
nfs_lookup_revalidate will see that the parent directory has changed and
will try to reverify the dentry by redoing a LOOKUP. That of course
fails, so the lookup code returns ESTALE.
The problem here is that d_revalidate is really a bad fit for this case.
What we really want to know at this point is whether the inode is still
good or not, but we don't really care what name it goes by or whether
the dcache is still valid.
Add a new d_op->d_weak_revalidate operation and have complete_walk call
that instead of d_revalidate. The intent there is to allow for a
"weaker" d_revalidate that just checks to see whether the inode is still
good. This is also gives us an opportunity to kill off the FS_REVAL_DOT
special casing.
[AV: changed method name, added note in porting, fixed confusion re
having it possibly called from RCU mode (it won't be)]
Cc: NeilBrown <neilb@suse.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The '->write_super' superblock method is gone, and this patch removes all the
references to 'write_super' from various pieces of the kernel documentation.
Cc: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
