Commit Graph

868 Commits

Author SHA1 Message Date
Al Viro
e55f1d1d13 Merge remote-tracking branch 'jk/vfs' into work.misc 2016-10-08 11:06:08 -04:00
Andreas Gruenbacher
fd50ecaddf vfs: Remove {get,set,remove}xattr inode operations
These inode operations are no longer used; remove them.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-10-07 21:48:36 -04:00
Linus Torvalds
d1f5323370 Merge branch 'work.splice_read' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull VFS splice updates from Al Viro:
 "There's a bunch of branches this cycle, both mine and from other folks
  and I'd rather send pull requests separately.

  This one is the conversion of ->splice_read() to ITER_PIPE iov_iter
  (and introduction of such). Gets rid of a lot of code in fs/splice.c
  and elsewhere; there will be followups, but these are for the next
  cycle...  Some pipe/splice-related cleanups from Miklos in the same
  branch as well"

* 'work.splice_read' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  pipe: fix comment in pipe_buf_operations
  pipe: add pipe_buf_steal() helper
  pipe: add pipe_buf_confirm() helper
  pipe: add pipe_buf_release() helper
  pipe: add pipe_buf_get() helper
  relay: simplify relay_file_read()
  switch default_file_splice_read() to use of pipe-backed iov_iter
  switch generic_file_splice_read() to use of ->read_iter()
  new iov_iter flavour: pipe-backed
  fuse_dev_splice_read(): switch to add_to_pipe()
  skb_splice_bits(): get rid of callback
  new helper: add_to_pipe()
  splice: lift pipe_lock out of splice_to_pipe()
  splice: switch get_iovec_page_array() to iov_iter
  splice_to_pipe(): don't open-code wakeup_pipe_readers()
  consistent treatment of EFAULT on O_DIRECT read/write
2016-10-07 15:36:58 -07:00
Miklos Szeredi
ca76f5b6bd pipe: add pipe_buf_steal() helper
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-10-05 18:23:59 -04:00
Miklos Szeredi
fba597db42 pipe: add pipe_buf_confirm() helper
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-10-05 18:23:59 -04:00
Miklos Szeredi
a779638cf6 pipe: add pipe_buf_release() helper
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-10-05 18:23:58 -04:00
Miklos Szeredi
7bf2d1df80 pipe: add pipe_buf_get() helper
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-10-05 18:23:57 -04:00
Al Viro
d82718e348 fuse_dev_splice_read(): switch to add_to_pipe()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-10-03 20:40:56 -04:00
Al Viro
8924feff66 splice: lift pipe_lock out of splice_to_pipe()
* splice_to_pipe() stops at pipe overflow and does *not* take pipe_lock
* ->splice_read() instances do the same
* vmsplice_to_pipe() and do_splice() (ultimate callers of splice_to_pipe())
  arrange for waiting, looping, etc. themselves.

That should make pipe_lock the outermost one.

Unfortunately, existing rules for the amount passed by vmsplice_to_pipe()
and do_splice() are quite ugly _and_ userland code can be easily broken
by changing those.  It's not even "no more than the maximal capacity of
this pipe" - it's "once we'd fed pipe->nr_buffers pages into the pipe,
leave instead of waiting".

Considering how poorly these rules are documented, let's try "wait for some
space to appear, unless given SPLICE_F_NONBLOCK, then push into pipe
and if we run into overflow, we are done".

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-10-03 20:40:55 -04:00
Miklos Szeredi
63401ccdb2 fuse: limit xattr returned size
Don't let userspace filesystem give bogus values for the size of xattr and
xattr list.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-10-03 11:06:05 +02:00
Miklos Szeredi
4680a7ee5d fuse: remove duplicate cs->offset assignment
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-10-01 07:32:33 +02:00
Miklos Szeredi
acbe5fda1f fuse: don't use fuse_ioctl_copy_user() helper
The two invocations share little code.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-10-01 07:32:33 +02:00
Al Viro
3daa9c5165 fuse_ioctl_copy_user(): don't open-code copy_page_{to,from}_iter()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-10-01 07:32:33 +02:00
Seth Forshee
703c73629f fuse: Use generic xattr ops
In preparation for posix acl support, rework fuse to use xattr handlers and
the generic setxattr/getxattr/listxattr callbacks.  Split the xattr code
out into it's own file, and promote symbols to module-global scope as
needed.

Functionally these changes have no impact, as fuse still uses a single
handler for all xattrs which uses the old callbacks.

Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-10-01 07:32:32 +02:00
Miklos Szeredi
29433a2991 fuse: get rid of fc->flags
Only two flags: "default_permissions" and "allow_other".  All other flags
are handled via bitfields.  So convert these two as well.  They don't
change during the lifetime of the filesystem, so this is quite safe.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-10-01 07:32:32 +02:00
Miklos Szeredi
cb3ae6d25a fuse: listxattr: verify xattr list
Make sure userspace filesystem is returning a well formed list of xattr
names (zero or more nonzero length, null terminated strings).

[Michael Theall: only verify in the nonzero size case]

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: <stable@vger.kernel.org>
2016-10-01 07:32:32 +02:00
Miklos Szeredi
bcb6f6d2b9 fuse: use timespec64
And check for valid nsec value before passing into timespec64_to_jiffies().

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-10-01 07:32:32 +02:00
Miklos Szeredi
f75fdf22b0 fuse: don't use ->d_time
Store in memory pointed to by ->d_fsdata.  Use ->d_init() to allocate the
storage.  Need to use RCU freeing because the data is used in RCU lookup
mode.

We could cast ->d_fsdata directly on 64bit archs, but I don't think this is
worth the extra complexity.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-10-01 07:32:32 +02:00
Seth Forshee
60bcc88ad1 fuse: Add posix ACL support
Add a new INIT flag, FUSE_POSIX_ACL, for negotiating ACL support with
userspace.  When it is set in the INIT response, ACL support will be
enabled.  ACL support also implies "default_permissions".

When ACL support is enabled, the kernel will cache and have responsibility
for enforcing ACLs.  ACL xattrs will be passed to userspace, which is
responsible for updating the ACLs in the filesystem, keeping the file mode
in sync, and inheritance of default ACLs when new filesystem nodes are
created.

Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-10-01 07:32:32 +02:00
Miklos Szeredi
5e940c1dd3 fuse: handle killpriv in userspace fs
Only userspace filesystem can do the killing of suid/sgid without races.
So introduce an INIT flag and negotiate support for this.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-10-01 07:32:32 +02:00
Miklos Szeredi
a09f99edde fuse: fix killing s[ug]id in setattr
Fuse allowed VFS to set mode in setattr in order to clear suid/sgid on
chown and truncate, and (since writeback_cache) write.  The problem with
this is that it'll potentially restore a stale mode.

The poper fix would be to let the filesystems do the suid/sgid clearing on
the relevant operations.  Possibly some are already doing it but there's no
way we can detect this.

So fix this by refreshing and recalculating the mode.  Do this only if
ATTR_KILL_S[UG]ID is set to not destroy performance for writes.  This is
still racy but the size of the window is reduced.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: <stable@vger.kernel.org>
2016-10-01 07:32:32 +02:00
Miklos Szeredi
5e2b8828ff fuse: invalidate dir dentry after chmod
Without "default_permissions" the userspace filesystem's lookup operation
needs to perform the check for search permission on the directory.

If directory does not allow search for everyone (this is quite rare) then
userspace filesystem has to set entry timeout to zero to make sure
permissions are always performed.

Changing the mode bits of the directory should also invalidate the
(previously cached) dentry to make sure the next lookup will have a chance
of updating the timeout, if needed.

Reported-by: Jean-Pierre André <jean-pierre.andre@wanadoo.fr>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: <stable@vger.kernel.org>
2016-10-01 07:32:32 +02:00
Deepa Dinamani
c2050a454c fs: Replace current_fs_time() with current_time()
current_fs_time() uses struct super_block* as an argument.
As per Linus's suggestion, this is changed to take struct
inode* as a parameter instead. This is because the function
is primarily meant for vfs inode timestamps.
Also the function was renamed as per Arnd's suggestion.

Change all calls to current_fs_time() to use the new
current_time() function instead. current_fs_time() will be
deleted.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-09-27 21:06:22 -04:00
Deepa Dinamani
078cd8279e fs: Replace CURRENT_TIME with current_time() for inode timestamps
CURRENT_TIME macro is not appropriate for filesystems as it
doesn't use the right granularity for filesystem timestamps.
Use current_time() instead.

CURRENT_TIME is also not y2038 safe.

This is also in preparation for the patch that transitions
vfs timestamps to use 64 bit time and hence make them
y2038 safe. As part of the effort current_time() will be
extended to do range checks. Hence, it is necessary for all
file system timestamps to use current_time(). Also,
current_time() will be transitioned along with vfs to be
y2038 safe.

Note that whenever a single call to current_time() is used
to change timestamps in different inodes, it is because they
share the same time granularity.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Felipe Balbi <balbi@kernel.org>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Acked-by: David Sterba <dsterba@suse.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-09-27 21:06:21 -04:00
Miklos Szeredi
2773bf00ae fs: rename "rename2" i_op to "rename"
Generated patch:

sed -i "s/\.rename2\t/\.rename\t\t/" `git grep -wl rename2`
sed -i "s/\brename2\b/rename/g" `git grep -wl rename2`

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-09-27 11:03:58 +02:00
Jan Kara
31051c85b5 fs: Give dentry to inode_change_ok() instead of inode
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>
2016-09-22 10:56:19 +02:00
Jan Kara
6249033076 fuse: Propagate dentry down to inode_change_ok()
To avoid clearing of capabilities or security related extended
attributes too early, inode_change_ok() will need to take dentry instead
of inode. Propagate it down to fuse_do_setattr().

Acked-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2016-09-22 10:56:19 +02:00
Miklos Szeredi
8fba54aebb fuse: direct-io: don't dirty ITER_BVEC pages
When reading from a loop device backed by a fuse file it deadlocks on
lock_page().

This is because the page is already locked by the read() operation done on
the loop device.  In this case we don't want to either lock the page or
dirty it.

So do what fs/direct-io.c does: only dirty the page for ITER_IOVEC vectors.

Reported-by: Sheng Yang <sheng@yasker.org>
Fixes: aa4d86163e ("block: loop: switch to VFS ITER_BVEC")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: <stable@vger.kernel.org> # v4.1+
Reviewed-by: Sheng Yang <sheng@yasker.org>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
Tested-by: Sheng Yang <sheng@yasker.org>
Tested-by: Ashish Samant <ashish.samant@oracle.com>
2016-08-24 18:17:04 +02:00
Linus Torvalds
835c92d43b Merge branch 'work.const-qstr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull qstr constification updates from Al Viro:
 "Fairly self-contained bunch - surprising lot of places passes struct
  qstr * as an argument when const struct qstr * would suffice; it
  complicates analysis for no good reason.

  I'd prefer to feed that separately from the assorted fixes (those are
  in #for-linus and with somewhat trickier topology)"

* 'work.const-qstr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  qstr: constify instances in adfs
  qstr: constify instances in lustre
  qstr: constify instances in f2fs
  qstr: constify instances in ext2
  qstr: constify instances in vfat
  qstr: constify instances in procfs
  qstr: constify instances in fuse
  qstr constify instances in fs/dcache.c
  qstr: constify instances in nfs
  qstr: constify instances in ocfs2
  qstr: constify instances in autofs4
  qstr: constify instances in hfs
  qstr: constify instances in hfsplus
  qstr: constify instances in logfs
  qstr: constify dentry_init_security
2016-08-06 09:49:02 -04:00
Al Viro
13983d062f qstr: constify instances in fuse
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-07-30 12:25:26 -04:00
Linus Torvalds
27ae0c41ed Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse updates from Miklos Szeredi:
 "This fixes error propagation from writeback to fsync/close for
  writeback cache mode as well as adding a missing capability flag to
  the INIT message.  The rest are cleanups.

  (The commits are recent but all the code actually sat in -next for a
  while now.  The recommits are due to conflict avoidance and the
  addition of Cc: stable@...)"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: use filemap_check_errors()
  mm: export filemap_check_errors() to modules
  fuse: fix wrong assignment of ->flags in fuse_send_init()
  fuse: fuse_flush must check mapping->flags for errors
  fuse: fsync() did not return IO errors
  fuse: don't mess with blocking signals
  new helper: wait_event_killable_exclusive()
  fuse: improve aio directIO write performance for size extending writes
2016-07-29 12:29:15 -07:00
Miklos Szeredi
4a7f4e88fe fuse: use filemap_check_errors()
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-07-29 14:10:57 +02:00
Wei Fang
9446385f05 fuse: fix wrong assignment of ->flags in fuse_send_init()
FUSE_HAS_IOCTL_DIR should be assigned to ->flags, it may be a typo.

Signed-off-by: Wei Fang <fangwei1@huawei.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 69fe05c90e ("fuse: add missing INIT flags")
Cc: <stable@vger.kernel.org>
2016-07-29 14:10:57 +02:00
Maxim Patlasov
9ebce595f6 fuse: fuse_flush must check mapping->flags for errors
fuse_flush() calls write_inode_now() that triggers writeback, but actual
writeback will happen later, on fuse_sync_writes(). If an error happens,
fuse_writepage_end() will set error bit in mapping->flags. So, we have to
check mapping->flags after fuse_sync_writes().

Signed-off-by: Maxim Patlasov <mpatlasov@virtuozzo.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 4d99ff8f12 ("fuse: Turn writeback cache on")
Cc: <stable@vger.kernel.org> # v3.15+
2016-07-29 14:10:57 +02:00
Alexey Kuznetsov
ac7f052b9e fuse: fsync() did not return IO errors
Due to implementation of fuse writeback filemap_write_and_wait_range() does
not catch errors. We have to do this directly after fuse_sync_writes()

Signed-off-by: Alexey Kuznetsov <kuznet@virtuozzo.com>
Signed-off-by: Maxim Patlasov <mpatlasov@virtuozzo.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 4d99ff8f12 ("fuse: Turn writeback cache on")
Cc: <stable@vger.kernel.org> # v3.15+
2016-07-29 14:10:57 +02:00
Linus Torvalds
1c88e19b0f Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton:
 "The rest of MM"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (101 commits)
  mm, compaction: simplify contended compaction handling
  mm, compaction: introduce direct compaction priority
  mm, thp: remove __GFP_NORETRY from khugepaged and madvised allocations
  mm, page_alloc: make THP-specific decisions more generic
  mm, page_alloc: restructure direct compaction handling in slowpath
  mm, page_alloc: don't retry initial attempt in slowpath
  mm, page_alloc: set alloc_flags only once in slowpath
  lib/stackdepot.c: use __GFP_NOWARN for stack allocations
  mm, kasan: switch SLUB to stackdepot, enable memory quarantine for SLUB
  mm, kasan: account for object redzone in SLUB's nearest_obj()
  mm: fix use-after-free if memory allocation failed in vma_adjust()
  zsmalloc: Delete an unnecessary check before the function call "iput"
  mm/memblock.c: fix index adjustment error in __next_mem_range_rev()
  mem-hotplug: alloc new page from a nearest neighbor node when mem-offline
  mm: optimize copy_page_to/from_iter_iovec
  mm: add cond_resched() to generic_swapfile_activate()
  Revert "mm, mempool: only set __GFP_NOMEMALLOC if there are free elements"
  mm, compaction: don't isolate PageWriteback pages in MIGRATE_SYNC_LIGHT mode
  mm: hwpoison: remove incorrect comments
  make __section_nr() more efficient
  ...
2016-07-28 16:36:48 -07:00
Mel Gorman
11fb998986 mm: move most file-based accounting to the node
There are now a number of accounting oddities such as mapped file pages
being accounted for on the node while the total number of file pages are
accounted on the zone.  This can be coped with to some extent but it's
confusing so this patch moves the relevant file-based accounted.  Due to
throttling logic in the page allocator for reliable OOM detection, it is
still necessary to track dirty and writeback pages on a per-zone basis.

[mgorman@techsingularity.net: fix NR_ZONE_WRITE_PENDING accounting]
  Link: http://lkml.kernel.org/r/1468404004-5085-5-git-send-email-mgorman@techsingularity.net
Link: http://lkml.kernel.org/r/1467970510-21195-20-git-send-email-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28 16:07:41 -07:00
Linus Torvalds
554828ee0d Merge branch 'salted-string-hash'
This changes the vfs dentry hashing to mix in the parent pointer at the
_beginning_ of the hash, rather than at the end.

That actually improves both the hash and the code generation, because we
can move more of the computation to the "static" part of the dcache
setup, and do less at lookup runtime.

It turns out that a lot of other hash users also really wanted to mix in
a base pointer as a 'salt' for the hash, and so the slightly extended
interface ends up working well for other cases too.

Users that want a string hash that is purely about the string pass in a
'salt' pointer of NULL.

* merge branch 'salted-string-hash':
  fs/dcache.c: Save one 32-bit multiply in dcache lookup
  vfs: make the string hashes salt the hash
2016-07-28 12:26:31 -07:00
Miklos Szeredi
0f7d93416d Merge branch 'for-miklos' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs into for-next 2016-07-21 11:14:30 +02:00
Al Viro
7d3a07fcb8 fuse: don't mess with blocking signals
just use wait_event_killable{,_exclusive}().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-07-19 03:08:27 -04:00
Al Viro
00699ad857 Use the right predicate in ->atomic_open() instances
->atomic_open() can be given an in-lookup dentry *or* a negative one
found in dcache.  Use d_in_lookup() to tell one from another, rather
than d_unhashed().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-07-05 16:02:23 -04:00
Ashish Sangwan
7879c4e58b fuse: improve aio directIO write performance for size extending writes
While sending the blocking directIO in fuse, the write request is broken
into sub-requests, each of default size 128k and all the requests are sent
in non-blocking background mode if async_dio mode is supported by libfuse.
The process which issue the write wait for the completion of all the
sub-requests. Sending multiple requests parallely gives a chance to perform
parallel writes in the user space fuse implementation if it is
multi-threaded and hence improves the performance.

When there is a size extending aio dio write, we switch to blocking mode so
that we can properly update the size of the file after completion of the
writes. However, in this situation all the sub-requests are sent in
serialized manner where the next request is sent only after receiving the
reply of the current request. Hence the multi-threaded user space
implementation is not utilized properly.

This patch changes the size extending aio dio behavior to exactly follow
blocking dio. For multi threaded fuse implementation having 10 threads and
using buffer size of 64MB to perform async directIO, we are getting double
the speed.

Signed-off-by: Ashish Sangwan <ashishsangwan2@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-06-30 13:14:10 +02:00
Miklos Szeredi
5c672ab3f0 fuse: serialize dirops by default
Negotiate with userspace filesystems whether they support parallel readdir
and lookup.  Disable parallelism by default for fear of breaking fuse
filesystems.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 9902af79c0 ("parallel lookups: actual switch to rwsem")
Fixes: d9b3dbdcfd ("fuse: switch to ->iterate_shared()")
2016-06-30 13:10:49 +02:00
Linus Torvalds
8387ff2577 vfs: make the string hashes salt the hash
We always mixed in the parent pointer into the dentry name hash, but we
did it late at lookup time.  It turns out that we can simplify that
lookup-time action by salting the hash with the parent pointer early
instead of late.

A few other users of our string hashes also wanted to mix in their own
pointers into the hash, and those are updated to use the same mechanism.

Hash users that don't have any particular initial salt can just use the
NULL pointer as a no-salt.

Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-06-10 20:21:46 -07:00
Al Viro
3767e255b3 switch ->setxattr() to passing dentry and inode separately
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>
2016-05-27 20:09:16 -04:00
Linus Torvalds
c2e7b20705 Merge branch 'work.preadv2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs cleanups from Al Viro:
 "More cleanups from Christoph"

* 'work.preadv2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  nfsd: use RWF_SYNC
  fs: add RWF_DSYNC aand RWF_SYNC
  ceph: use generic_write_sync
  fs: simplify the generic_write_sync prototype
  fs: add IOCB_SYNC and IOCB_DSYNC
  direct-io: remove the offset argument to dio_complete
  direct-io: eliminate the offset argument to ->direct_IO
  xfs: eliminate the pos variable in xfs_file_dio_aio_write
  filemap: remove the pos argument to generic_file_direct_write
  filemap: remove pos variables in generic_file_read_iter
2016-05-17 15:05:23 -07:00
Al Viro
0e0162bb8c Merge branch 'ovl-fixes' into for-linus
Backmerge to resolve a conflict in ovl_lookup_real();
"ovl_lookup_real(): use lookup_one_len_unlocked()" instead,
but it was too late in the cycle to rebase.
2016-05-17 02:17:59 -04:00
Al Viro
d9b3dbdcfd fuse: switch to ->iterate_shared()
Switch dcache pre-seeding on readdir to d_alloc_parallel();
nothing else is needed.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-02 19:49:31 -04:00
Al Viro
84695ffee7 Merge getxattr prototype change into work.lookups
The rest of work.xattr stuff isn't needed for this branch
2016-05-02 19:45:47 -04:00
Christoph Hellwig
c8b8e32d70 direct-io: eliminate the offset argument to ->direct_IO
Including blkdev_direct_IO and dax_do_io.  It has to be ki_pos to actually
work, so eliminate the superflous argument.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-01 19:58:39 -04:00
Christoph Hellwig
1af5bb491f filemap: remove the pos argument to generic_file_direct_write
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-01 19:58:39 -04:00
Ashish Samant
2c932d4c91 fuse: Fix return value from fuse_get_user_pages()
fuse_get_user_pages() should return error or 0. Otherwise fuse_direct_io
read will not return 0 to indicate that read has completed.

Fixes: 742f992708 ("fuse: return patrial success from fuse_direct_io()")
Signed-off-by: Ashish Samant <ashish.samant@oracle.com>
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-04-25 13:01:04 +02:00
Al Viro
ce23e64013 ->getxattr(): pass dentry and inode as separate arguments
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-04-11 00:48:00 -04:00
Kirill A. Shutemov
09cbfeaf1a mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized.  And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE.  And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special.  They are
not.

The changes are pretty straight-forward:

 - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

 - page_cache_get() -> get_page();

 - page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below.  For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach.  I'll
fix them manually in a separate patch.  Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-04 10:41:08 -07:00
Ashish Samant
742f992708 fuse: return patrial success from fuse_direct_io()
If a user calls writev/readv in direct io mode with partially valid data
in the iovec array such that any vector other than the first one in the
array contains invalid data, we currently return the error for the invalid
iovec.

Instead, we should return the number of bytes already written/read and not
the error as we do in the non direct_io case.

Reported-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Signed-off-by: Ashish Samant <ashish.samant@oracle.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-03-16 14:38:31 +01:00
Seth Forshee
744742d692 fuse: Add reference counting for fuse_io_priv
The 'reqs' member of fuse_io_priv serves two purposes. First is to track
the number of oustanding async requests to the server and to signal that
the io request is completed. The second is to be a reference count on the
structure to know when it can be freed.

For sync io requests these purposes can be at odds.  fuse_direct_IO() wants
to block until the request is done, and since the signal is sent when
'reqs' reaches 0 it cannot keep a reference to the object. Yet it needs to
use the object after the userspace server has completed processing
requests. This leads to some handshaking and special casing that it
needlessly complicated and responsible for at least one race condition.

It's much cleaner and safer to maintain a separate reference count for the
object lifecycle and to let 'reqs' just be a count of outstanding requests
to the userspace server. Then we can know for sure when it is safe to free
the object without any handshaking or special cases.

The catch here is that most of the time these objects are stack allocated
and should not be freed. Initializing these objects with a single reference
that is never released prevents accidental attempts to free the objects.

Fixes: 9d5722b777 ("fuse: handle synchronous iocbs internally")
Cc: stable@vger.kernel.org # v4.1+
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-03-14 15:02:51 +01:00
Robert Doebbelin
7cabc61e01 fuse: do not use iocb after it may have been freed
There's a race in fuse_direct_IO(), whereby is_sync_kiocb() is called on an
iocb that could have been freed if async io has already completed.  The fix
in this case is simple and obvious: cache the result before starting io.

It was discovered by KASan:

kernel: ==================================================================
kernel: BUG: KASan: use after free in fuse_direct_IO+0xb1a/0xcc0 at addr ffff88036c414390

Signed-off-by: Robert Doebbelin <robert@quobyte.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: bcba24ccdc ("fuse: enable asynchronous processing direct IO")
Cc: <stable@vger.kernel.org> # 3.10+
2016-03-14 15:02:50 +01:00
Al Viro
5955102c99 wrappers for ->i_mutex access
parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
inode_foo(inode) being mutex_foo(&inode->i_mutex).

Please, use those for access to ->i_mutex; over the coming cycle
->i_mutex will become rwsem, with ->lookup() done with it held
only shared.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 18:04:28 -05:00
Linus Torvalds
5c89e9ea7e Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse updates from Miklos Szeredi:
 "This adds SEEK_HOLE and SEEK_DATA support in lseek"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: add support for SEEK_HOLE and SEEK_DATA in lseek
2016-01-21 12:14:24 -08:00
Vladimir Davydov
5d097056c9 kmemcg: account certain kmem allocations to memcg
Mark those kmem allocations that are known to be easily triggered from
userspace as __GFP_ACCOUNT/SLAB_ACCOUNT, which makes them accounted to
memcg.  For the list, see below:

 - threadinfo
 - task_struct
 - task_delay_info
 - pid
 - cred
 - mm_struct
 - vm_area_struct and vm_region (nommu)
 - anon_vma and anon_vma_chain
 - signal_struct
 - sighand_struct
 - fs_struct
 - files_struct
 - fdtable and fdtable->full_fds_bits
 - dentry and external_name
 - inode for all filesystems. This is the most tedious part, because
   most filesystems overwrite the alloc_inode method.

The list is far from complete, so feel free to add more objects.
Nevertheless, it should be close to "account everything" approach and
keep most workloads within bounds.  Malevolent users will be able to
breach the limit, but this was possible even with the former "account
everything" approach (simply because it did not account everything in
fact).

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Greg Thelen <gthelen@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-14 16:00:49 -08:00
Linus Torvalds
32fb378437 Merge branch 'work.symlinks' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs RCU symlink updates from Al Viro:
 "Replacement of ->follow_link/->put_link, allowing to stay in RCU mode
  even if the symlink is not an embedded one.

  No changes since the mailbomb on Jan 1"

* 'work.symlinks' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  switch ->get_link() to delayed_call, kill ->put_link()
  kill free_page_put_link()
  teach nfs_get_link() to work in RCU mode
  teach proc_self_get_link()/proc_thread_self_get_link() to work in RCU mode
  teach shmem_get_link() to work in RCU mode
  teach page_get_link() to work in RCU mode
  replace ->follow_link() with new method that could stay in RCU mode
  don't put symlink bodies in pagecache into highmem
  namei: page_getlink() and page_follow_link_light() are the same thing
  ufs: get rid of ->setattr() for symlinks
  udf: don't duplicate page_symlink_inode_operations
  logfs: don't duplicate page_symlink_inode_operations
  switch befs long symlinks to page_symlink_operations
2016-01-11 13:13:23 -08:00
Al Viro
fceef393a5 switch ->get_link() to delayed_call, kill ->put_link()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-30 13:01:03 -05:00
Al Viro
cd3417c8fc kill free_page_put_link()
all callers are better off with kfree_put_link()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-29 16:03:53 -05:00
Linus Torvalds
732c4a9e14 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse fixes from Miklos Szeredi:
 "Two bugfixes, both bound for -stable"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: break infinite loop in fuse_fill_write_pages()
  cuse: fix memory leak
2015-12-11 10:56:41 -08:00
Al Viro
6b2553918d replace ->follow_link() with new method that could stay in RCU mode
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>
2015-12-08 22:41:54 -05:00
Ravishankar N
0b5da8db14 fuse: add support for SEEK_HOLE and SEEK_DATA in lseek
A useful performance improvement for accessing virtual machine images
via FUSE mount.

See https://bugzilla.redhat.com/show_bug.cgi?id=1220173 for a use-case
for glusterFS.

Signed-off-by: Ravishankar N <ravishankar@redhat.com>
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
2015-11-10 10:32:37 +01:00
Roman Gushchin
3ca8138f01 fuse: break infinite loop in fuse_fill_write_pages()
I got a report about unkillable task eating CPU. Further
investigation shows, that the problem is in the fuse_fill_write_pages()
function. If iov's first segment has zero length, we get an infinite
loop, because we never reach iov_iter_advance() call.

Fix this by calling iov_iter_advance() before repeating an attempt to
copy data from userspace.

A similar problem is described in 124d3b7041 ("fix writev regression:
pan hanging unkillable and un-straceable"). If zero-length segmend
is followed by segment with invalid address,
iov_iter_fault_in_readable() checks only first segment (zero-length),
iov_iter_copy_from_user_atomic() skips it, fails at second and
returns zero -> goto again without skipping zero-length segment.

Patch calls iov_iter_advance() before goto again: we'll skip zero-length
segment at second iteraction and iov_iter_fault_in_readable() will detect
invalid address.

Special thanks to Konstantin Khlebnikov, who helped a lot with the commit
description.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Maxim Patlasov <mpatlasov@parallels.com>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Roman Gushchin <klamm@yandex-team.ru>
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Fixes: ea9b9907b8 ("fuse: implement perform_write")
Cc: <stable@vger.kernel.org>
2015-11-10 10:32:37 +01:00
Miklos Szeredi
2c5816b4be cuse: fix memory leak
The problem is that fuse_dev_alloc() acquires an extra reference to cc.fc,
and the original ref count is never dropped.

Reported-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Fixes: cc080e9e9b ("fuse: introduce per-instance fuse_dev structure")
Cc: <stable@vger.kernel.org> # v4.2+
2015-11-10 10:32:36 +01:00
Benjamin Coddington
4f6563677a Move locks API users to locks_lock_inode_wait()
Instead of having users check for FL_POSIX or FL_FLOCK to call the correct
locks API function, use the check within locks_lock_inode_wait().  This
allows for some later cleanup.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
2015-10-22 14:57:36 -04:00
Jann Horn
8ed1f0e22f fs/fuse: fix ioctl type confusion
fuse_dev_ioctl() performed fuse_get_dev() on a user-supplied fd,
leading to a type confusion issue. Fix it by checking file->f_op.

Signed-off-by: Jann Horn <jann@thejh.net>
Acked-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-08-16 12:35:44 -07:00
Linus Torvalds
1dc51b8288 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
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
  ...
2015-07-04 19:36:06 -07:00
Linus Torvalds
0cbee99269 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull user namespace updates from Eric Biederman:
 "Long ago and far away when user namespaces where young it was realized
  that allowing fresh mounts of proc and sysfs with only user namespace
  permissions could violate the basic rule that only root gets to decide
  if proc or sysfs should be mounted at all.

  Some hacks were put in place to reduce the worst of the damage could
  be done, and the common sense rule was adopted that fresh mounts of
  proc and sysfs should allow no more than bind mounts of proc and
  sysfs.  Unfortunately that rule has not been fully enforced.

  There are two kinds of gaps in that enforcement.  Only filesystems
  mounted on empty directories of proc and sysfs should be ignored but
  the test for empty directories was insufficient.  So in my tree
  directories on proc, sysctl and sysfs that will always be empty are
  created specially.  Every other technique is imperfect as an ordinary
  directory can have entries added even after a readdir returns and
  shows that the directory is empty.  Special creation of directories
  for mount points makes the code in the kernel a smidge clearer about
  it's purpose.  I asked container developers from the various container
  projects to help test this and no holes were found in the set of mount
  points on proc and sysfs that are created specially.

  This set of changes also starts enforcing the mount flags of fresh
  mounts of proc and sysfs are consistent with the existing mount of
  proc and sysfs.  I expected this to be the boring part of the work but
  unfortunately unprivileged userspace winds up mounting fresh copies of
  proc and sysfs with noexec and nosuid clear when root set those flags
  on the previous mount of proc and sysfs.  So for now only the atime,
  read-only and nodev attributes which userspace happens to keep
  consistent are enforced.  Dealing with the noexec and nosuid
  attributes remains for another time.

  This set of changes also addresses an issue with how open file
  descriptors from /proc/<pid>/ns/* are displayed.  Recently readlink of
  /proc/<pid>/fd has been triggering a WARN_ON that has not been
  meaningful since it was added (as all of the code in the kernel was
  converted) and is not now actively wrong.

  There is also a short list of issues that have not been fixed yet that
  I will mention briefly.

  It is possible to rename a directory from below to above a bind mount.
  At which point any directory pointers below the renamed directory can
  be walked up to the root directory of the filesystem.  With user
  namespaces enabled a bind mount of the bind mount can be created
  allowing the user to pick a directory whose children they can rename
  to outside of the bind mount.  This is challenging to fix and doubly
  so because all obvious solutions must touch code that is in the
  performance part of pathname resolution.

  As mentioned above there is also a question of how to ensure that
  developers by accident or with purpose do not introduce exectuable
  files on sysfs and proc and in doing so introduce security regressions
  in the current userspace that will not be immediately obvious and as
  such are likely to require breaking userspace in painful ways once
  they are recognized"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  vfs: Remove incorrect debugging WARN in prepend_path
  mnt: Update fs_fully_visible to test for permanently empty directories
  sysfs: Create mountpoints with sysfs_create_mount_point
  sysfs: Add support for permanently empty directories to serve as mount points.
  kernfs: Add support for always empty directories.
  proc: Allow creating permanently empty directories that serve as mount points
  sysctl: Allow creating permanently empty directories that serve as mountpoints.
  fs: Add helper functions for permanently empty directories.
  vfs: Ignore unlocked mounts in fs_fully_visible
  mnt: Modify fs_fully_visible to deal with locked ro nodev and atime
  mnt: Refactor the logic for mounting sysfs and proc in a user namespace
2015-07-03 15:20:57 -07:00
Linus Torvalds
a7ba4bf5e7 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse updates from Miklos Szeredi:
 "This is the start of improving fuse scalability.

  An input queue and a processing queue is split out from the monolithic
  fuse connection, each of those having their own spinlock.  The end of
  the patchset adds the ability to clone a fuse connection.  This means,
  that instead of having to read/write requests/answers on a single fuse
  device fd, the fuse daemon can have multiple distinct file descriptors
  open.  Each of those can be used to receive requests and send answers,
  currently the only constraint is that a request must be answered on
  the same fd as it was read from.

  This can be extended further to allow binding a device clone to a
  specific CPU or NUMA node.

  Based on a patchset by Srinivas Eeda and Ashish Samant.  Thanks to
  Ashish for the review of this series"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: (40 commits)
  fuse: update MAINTAINERS entry
  fuse: separate pqueue for clones
  fuse: introduce per-instance fuse_dev structure
  fuse: device fd clone
  fuse: abort: no fc->lock needed for request ending
  fuse: no fc->lock for pqueue parts
  fuse: no fc->lock in request_end()
  fuse: cleanup request_end()
  fuse: request_end(): do once
  fuse: add req flag for private list
  fuse: pqueue locking
  fuse: abort: group pqueue accesses
  fuse: cleanup fuse_dev_do_read()
  fuse: move list_del_init() from request_end() into callers
  fuse: duplicate ->connected in pqueue
  fuse: separate out processing queue
  fuse: simplify request_wait()
  fuse: no fc->lock for iqueue parts
  fuse: allow interrupt queuing without fc->lock
  fuse: iqueue locking
  ...
2015-07-02 11:21:26 -07:00
Eric W. Biederman
f9bb48825a sysfs: Create mountpoints with sysfs_create_mount_point
This allows for better documentation in the code and
it allows for a simpler and fully correct version of
fs_fully_visible to be written.

The mount points converted and their filesystems are:
/sys/hypervisor/s390/       s390_hypfs
/sys/kernel/config/         configfs
/sys/kernel/debug/          debugfs
/sys/firmware/efi/efivars/  efivarfs
/sys/fs/fuse/connections/   fusectl
/sys/fs/pstore/             pstore
/sys/kernel/tracing/        tracefs
/sys/fs/cgroup/             cgroup
/sys/kernel/security/       securityfs
/sys/fs/selinux/            selinuxfs
/sys/fs/smackfs/            smackfs

Cc: stable@vger.kernel.org
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-01 10:36:47 -05:00
Miklos Szeredi
c3696046be fuse: separate pqueue for clones
Make each fuse device clone refer to a separate processing queue.  The only
constraint on userspace code is that the request answer must be written to
the same device clone as it was read off.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2015-07-01 16:26:09 +02:00
Miklos Szeredi
cc080e9e9b fuse: introduce per-instance fuse_dev structure
Allow fuse device clones to refer to be distinguished.  This patch just
adds the infrastructure by associating a separate "struct fuse_dev" with
each clone.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:08 +02:00
Miklos Szeredi
00c570f4ba fuse: device fd clone
Allow an open fuse device to be "cloned".  Userspace can create a clone by:

      newfd = open("/dev/fuse", O_RDWR)
      ioctl(newfd, FUSE_DEV_IOC_CLONE, &oldfd);

At this point newfd will refer to the same fuse connection as oldfd.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:08 +02:00
Miklos Szeredi
ee314a870e fuse: abort: no fc->lock needed for request ending
In fuse_abort_conn() when all requests are on private lists we no longer
need fc->lock protection.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:08 +02:00
Miklos Szeredi
46c34a348b fuse: no fc->lock for pqueue parts
Remove fc->lock protection from processing queue members, now protected by
fpq->lock.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:07 +02:00
Miklos Szeredi
efe2800fac fuse: no fc->lock in request_end()
No longer need to call request_end() with the connection lock held.  We
still protect the background counters and queue with fc->lock, so acquire
it if necessary.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:07 +02:00
Miklos Szeredi
1e6881c36e fuse: cleanup request_end()
Now that we atomically test having already done everything we no longer
need other protection.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:07 +02:00
Miklos Szeredi
365ae710df fuse: request_end(): do once
When the connection is aborted it is possible that request_end() will be
called twice.  Use atomic test and set to do the actual ending only once.

test_and_set_bit() also provides the necessary barrier semantics so no
explicit smp_wmb() is necessary.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:06 +02:00
Miklos Szeredi
77cd9d488b fuse: add req flag for private list
When an unlocked request is aborted, it is moved from fpq->io to a private
list.  Then, after unlocking fpq->lock, the private list is processed and
the requests are finished off.

To protect the private list, we need to mark the request with a flag, so if
in the meantime the request is unlocked the list is not corrupted.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:06 +02:00
Miklos Szeredi
45a91cb1a4 fuse: pqueue locking
Add a fpq->lock for protecting members of struct fuse_pqueue and FR_LOCKED
request flag.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:06 +02:00
Miklos Szeredi
24b4d33d46 fuse: abort: group pqueue accesses
Rearrange fuse_abort_conn() so that processing queue accesses are grouped
together.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:05 +02:00
Miklos Szeredi
82cbdcd320 fuse: cleanup fuse_dev_do_read()
- locked list_add() + list_del_init() cancel out

 - common handling of case when request is ended here in the read phase

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:05 +02:00
Miklos Szeredi
f377cb799e fuse: move list_del_init() from request_end() into callers
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2015-07-01 16:26:04 +02:00
Miklos Szeredi
e96edd94d0 fuse: duplicate ->connected in pqueue
This will allow checking ->connected just with the processing queue lock.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:04 +02:00
Miklos Szeredi
3a2b5b9cd9 fuse: separate out processing queue
This is just two fields: fc->io and fc->processing.

This patch just rearranges the fields, no functional change.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:04 +02:00
Miklos Szeredi
5250921bb0 fuse: simplify request_wait()
wait_event_interruptible_exclusive_locked() will do everything
request_wait() does, so replace it.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:03 +02:00
Miklos Szeredi
fd22d62ed0 fuse: no fc->lock for iqueue parts
Remove fc->lock protection from input queue members, now protected by
fiq->waitq.lock.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:03 +02:00
Miklos Szeredi
8f7bb368db fuse: allow interrupt queuing without fc->lock
Interrupt is only queued after the request has been sent to userspace.
This is either done in request_wait_answer() or fuse_dev_do_read()
depending on which state the request is in at the time of the interrupt.
If it's not yet sent, then queuing the interrupt is postponed until the
request is read.  Otherwise (the request has already been read and is
waiting for an answer) the interrupt is queued immedidately.

We want to call queue_interrupt() without fc->lock protection, in which
case there can be a race between the two functions:

 - neither of them queue the interrupt (thinking the other one has already
   done it).

 - both of them queue the interrupt

The first one is prevented by adding memory barriers, the second is
prevented by checking (under fiq->waitq.lock) if the interrupt has already
been queued.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2015-07-01 16:26:03 +02:00
Miklos Szeredi
4ce6081260 fuse: iqueue locking
Use fiq->waitq.lock for protecting members of struct fuse_iqueue and
FR_PENDING request flag, previously protected by fc->lock.

Following patches will remove fc->lock protection from these members.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:02 +02:00
Miklos Szeredi
ef75925886 fuse: dev read: split list_move
Different lists will need different locks.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:02 +02:00
Miklos Szeredi
8c91189a2a fuse: abort: group iqueue accesses
Rearrange fuse_abort_conn() so that input queue accesses are grouped
together.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:02 +02:00
Miklos Szeredi
e16714d875 fuse: duplicate ->connected in iqueue
This will allow checking ->connected just with the input queue lock.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:01 +02:00
Miklos Szeredi
f88996a933 fuse: separate out input queue
The input queue contains normal requests (fc->pending), forgets
(fc->forget_*) and interrupts (fc->interrupts).  There's also fc->waitq and
fc->fasync for waking up the readers of the fuse device when a request is
available.

The fc->reqctr is also moved to the input queue (assigned to the request
when the request is added to the input queue.

This patch just rearranges the fields, no functional change.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:01 +02:00
Miklos Szeredi
33e14b4dfd fuse: req state use flags
Use flags for representing the state in fuse_req.  This is needed since
req->list will be protected by different locks in different states, hence
we'll want the state itself to be split into distinct bits, each protected
with the relevant lock in that state.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2015-07-01 16:26:01 +02:00
Miklos Szeredi
7a3b2c7547 fuse: simplify req states
FUSE_REQ_INIT is actually the same state as FUSE_REQ_PENDING and
FUSE_REQ_READING and FUSE_REQ_WRITING can be merged into a common
FUSE_REQ_IO state.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:00 +02:00
Miklos Szeredi
c47752673a fuse: don't hold lock over request_wait_answer()
Only hold fc->lock over sections of request_wait_answer() that actually
need it.  If wait_event_interruptible() returns zero, it means that the
request finished.  Need to add memory barriers, though, to make sure that
all relevant data in the request is synchronized.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2015-07-01 16:26:00 +02:00
Miklos Szeredi
7d2e0a099c fuse: simplify unique ctr
Since it's a 64bit counter, it's never gonna wrap around.  Remove code
dealing with that possibility.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:00 +02:00
Miklos Szeredi
41f982747e fuse: rework abort
Splice fc->pending and fc->processing lists into a common kill list while
holding fc->lock.

By the time we release fc->lock, pending and processing lists are empty and
the io list contains only locked requests.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:59 +02:00
Miklos Szeredi
b716d42538 fuse: fold helpers into abort
Fold end_io_requests() and end_queued_requests() into fuse_abort_conn().

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:59 +02:00
Miklos Szeredi
dc00809a53 fuse: use per req lock for lock/unlock_request()
Reuse req->waitq.lock for protecting FR_ABORTED and FR_LOCKED flags.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:58 +02:00
Miklos Szeredi
825d6d3395 fuse: req use bitops
Finer grained locking will mean there's no single lock to protect
modification of bitfileds in fuse_req.

So move to using bitops.  Can use the non-atomic variants for those which
happen while the request definitely has only one reference.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:58 +02:00
Miklos Szeredi
0d8e84b043 fuse: simplify request abort
- don't end the request while req->locked is true

 - make unlock_request() return an error if the connection was aborted

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:58 +02:00
Miklos Szeredi
ccd0a0bd16 fuse: call fuse_abort_conn() in dev release
fuse_abort_conn() does all the work done by fuse_dev_release() and more.
"More" consists of:

	end_io_requests(fc);
	wake_up_all(&fc->waitq);
	kill_fasync(&fc->fasync, SIGIO, POLL_IN);

All of which should be no-op (WARN_ON's added).

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:57 +02:00
Miklos Szeredi
f0139aa819 fuse: fold fuse_request_send_nowait() into single caller
And the same with fuse_request_send_nowait_locked().

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:57 +02:00
Miklos Szeredi
de15522646 fuse: check conn_error earlier
fc->conn_error is set once in FUSE_INIT reply and never cleared.  Check it
in request allocation, there's no sense in doing all the preparation if
sending will surely fail.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:57 +02:00
Miklos Szeredi
5437f24172 fuse: account as waiting before queuing for background
Move accounting of fc->num_waiting to the point where the request actually
starts waiting.  This is earlier than the current queue_request() for
background requests, since they might be waiting on the fc->bg_queue before
being queued on fc->pending.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:56 +02:00
Miklos Szeredi
73e0e73844 fuse: reset waiting
Reset req->waiting in fuse_put_request().  This is needed for correct
accounting in fc->num_waiting for reserved requests.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2015-07-01 16:25:56 +02:00
Miklos Szeredi
42dc6211c5 fuse: fix background request if not connected
request_end() expects fc->num_background and fc->active_background to have
been incremented, which is not the case in fuse_request_send_nowait()
failure path.  So instead just call the ->end() callback (which is actually
set by all callers).

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:56 +02:00
Miklos Szeredi
0ad0b3255a fuse: initialize fc->release before calling it
fc->release is called from fuse_conn_put() which was used in the error
cleanup before fc->release was initialized.

[Jeremiah Mahler <jmmahler@gmail.com>: assign fc->release after calling
fuse_conn_init(fc) instead of before.]

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Fixes: a325f9b922 ("fuse: update fuse_conn_init() and separate out fuse_conn_kill()")
Cc: <stable@vger.kernel.org> #v2.6.31+
2015-07-01 16:25:55 +02:00
Linus Torvalds
e4bc13adfd Merge branch 'for-4.2/writeback' of git://git.kernel.dk/linux-block
Pull cgroup writeback support from Jens Axboe:
 "This is the big pull request for adding cgroup writeback support.

  This code has been in development for a long time, and it has been
  simmering in for-next for a good chunk of this cycle too.  This is one
  of those problems that has been talked about for at least half a
  decade, finally there's a solution and code to go with it.

  Also see last weeks writeup on LWN:

        http://lwn.net/Articles/648292/"

* 'for-4.2/writeback' of git://git.kernel.dk/linux-block: (85 commits)
  writeback, blkio: add documentation for cgroup writeback support
  vfs, writeback: replace FS_CGROUP_WRITEBACK with SB_I_CGROUPWB
  writeback: do foreign inode detection iff cgroup writeback is enabled
  v9fs: fix error handling in v9fs_session_init()
  bdi: fix wrong error return value in cgwb_create()
  buffer: remove unusued 'ret' variable
  writeback: disassociate inodes from dying bdi_writebacks
  writeback: implement foreign cgroup inode bdi_writeback switching
  writeback: add lockdep annotation to inode_to_wb()
  writeback: use unlocked_inode_to_wb transaction in inode_congested()
  writeback: implement unlocked_inode_to_wb transaction and use it for stat updates
  writeback: implement [locked_]inode_to_wb_and_lock_list()
  writeback: implement foreign cgroup inode detection
  writeback: make writeback_control track the inode being written back
  writeback: relocate wb[_try]_get(), wb_put(), inode_{attach|detach}_wb()
  mm: vmscan: disable memcg direct reclaim stalling if cgroup writeback support is in use
  writeback: implement memcg writeback domain based throttling
  writeback: reset wb_domain->dirty_limit[_tstmp] when memcg domain size changes
  writeback: implement memcg wb_domain
  writeback: update wb_over_bg_thresh() to use wb_domain aware operations
  ...
2015-06-25 16:00:17 -07:00
Jan Kara
5fa8e0a1c6 fs: Rename file_remove_suid() to file_remove_privs()
file_remove_suid() is a misnomer since it removes also file capabilities
stored in xattrs and sets S_NOSEC flag. Also should_remove_suid() tells
something else than whether file_remove_suid() call is necessary which
leads to bugs.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-23 18:01:08 -04:00
Tejun Heo
93f78d8828 writeback: move backing_dev_info->bdi_stat[] into bdi_writeback
Currently, a bdi (backing_dev_info) embeds single wb (bdi_writeback)
and the role of the separation is unclear.  For cgroup support for
writeback IOs, a bdi will be updated to host multiple wb's where each
wb serves writeback IOs of a different cgroup on the bdi.  To achieve
that, a wb should carry all states necessary for servicing writeback
IOs for a cgroup independently.

This patch moves bdi->bdi_stat[] into wb.

* enum bdi_stat_item is renamed to wb_stat_item and the prefix of all
  enums is changed from BDI_ to WB_.

* BDI_STAT_BATCH() -> WB_STAT_BATCH()

* [__]{add|inc|dec|sum}_wb_stat(bdi, ...) -> [__]{add|inc}_wb_stat(wb, ...)

* bdi_stat[_error]() -> wb_stat[_error]()

* bdi_writeout_inc() -> wb_writeout_inc()

* stat init is moved to bdi_wb_init() and bdi_wb_exit() is added and
  frees stat.

* As there's still only one bdi_writeback per backing_dev_info, all
  uses of bdi->stat[] are mechanically replaced with bdi->wb.stat[]
  introducing no behavior changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:33:34 -06:00
Al Viro
ecc087ff14 new helper: free_page_put_link()
similar to kfree_put_link()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-05-11 08:13:13 -04:00
Al Viro
5f2c4179e1 switch ->put_link() from dentry to inode
only one instance looks at that argument at all; that sole
exception wants inode rather than dentry.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-05-11 08:13:12 -04:00
Al Viro
6e77137b36 don't pass nameidata to ->follow_link()
its only use is getting passed to nd_jump_link(), which can obtain
it from current->nameidata

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-05-10 22:20:15 -04:00
Al Viro
680baacbca new ->follow_link() and ->put_link() calling conventions
a) instead of storing the symlink body (via nd_set_link()) and returning
an opaque pointer later passed to ->put_link(), ->follow_link() _stores_
that opaque pointer (into void * passed by address by caller) and returns
the symlink body.  Returning ERR_PTR() on error, NULL on jump (procfs magic
symlinks) and pointer to symlink body for normal symlinks.  Stored pointer
is ignored in all cases except the last one.

Storing NULL for opaque pointer (or not storing it at all) means no call
of ->put_link().

b) the body used to be passed to ->put_link() implicitly (via nameidata).
Now only the opaque pointer is.  In the cases when we used the symlink body
to free stuff, ->follow_link() now should store it as opaque pointer in addition
to returning it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-05-10 22:19:45 -04:00
David Howells
2b0143b5c9 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>
2015-04-15 15:06:57 -04:00
Al Viro
2ba48ce513 mirror O_APPEND and O_DIRECT into iocb->ki_flags
... avoiding write_iter/fcntl races.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11 22:30:22 -04:00
Al Viro
3309dd04cb switch generic_write_checks() to iocb and iter
... returning -E... upon error and amount of data left in iter after
(possible) truncation upon success.  Note, that normal case gives
a non-zero (positive) return value, so any tests for != 0 _must_ be
updated.

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

Conflicts:
	fs/ext4/file.c
2015-04-11 22:30:21 -04:00
Al Viro
6b775b18ee fuse: ->direct_IO() doesn't need generic_write_checks()
already done by caller.  We used to call __fuse_direct_write(), which
called generic_write_checks(); now the former got expanded, bringing
the latter to the surface.  It used to be called all along and calling
it from there had been wrong all along...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11 22:29:50 -04:00
Al Viro
0fa6b005af generic_write_checks(): drop isblk argument
all remaining callers are passing 0; some just obscure that fact.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11 22:29:48 -04:00
Omar Sandoval
22c6186ece direct_IO: remove rw from a_ops->direct_IO()
Now that no one is using rw, remove it completely.

Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11 22:29:45 -04:00
Omar Sandoval
6f67376318 direct_IO: use iov_iter_rw() instead of rw everywhere
The rw parameter to direct_IO is redundant with iov_iter->type, and
treated slightly differently just about everywhere it's used: some users
do rw & WRITE, and others do rw == WRITE where they should be doing a
bitwise check. Simplify this with the new iov_iter_rw() helper, which
always returns either READ or WRITE.

Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11 22:29:45 -04:00
Al Viro
6c09e94a32 fuse: use iov_iter_get_pages() for non-splice path
store reference to iter instead of that to iovec

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11 22:29:41 -04:00
Al Viro
fbdbacca61 fuse: switch to ->read_iter/->write_iter
we just change the calling conventions here; more work to follow.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11 22:29:41 -04:00
Al Viro
5d5d568975 make new_sync_{read,write}() static
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>
2015-04-11 22:29:40 -04:00
Al Viro
812408fb51 expand __fuse_direct_write() in both callers
it's actually shorter that way *and* later we'll want iocb in scope
of generic_write_check() caller.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11 22:27:53 -04:00
Al Viro
1531626364 fuse: switch fuse_direct_io_file_operations to ->{read,write}_iter()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11 22:27:53 -04:00
Al Viro
cfa86a7412 cuse: switch to iov_iter
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11 22:27:52 -04:00
Al Viro
c0fec3a98b Merge branch 'iocb' into for-next 2015-04-11 22:24:41 -04:00
Christoph Hellwig
e2e40f2c1e fs: move struct kiocb to fs.h
struct kiocb now is a generic I/O container, so move it to fs.h.
Also do a #include diet for aio.h while we're at it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-25 20:28:11 -04:00
Tom Van Braeckel
94e4fe2cab fuse: explicitly set /dev/fuse file's private_data
The misc subsystem (which is used for /dev/fuse) initializes private_data to
point to the misc device when a driver has registered a custom open file
operation, and initializes it to NULL when a custom open file operation has
*not* been provided.

This subtle quirk is confusing, to the point where kernel code registers
*empty* file open operations to have private_data point to the misc device
structure. And it leads to bugs, where the addition or removal of a custom open
file operation surprisingly changes the initial contents of a file's
private_data structure.

So to simplify things in the misc subsystem, a patch [1] has been proposed to
*always* set the private_data to point to the misc device, instead of only
doing this when a custom open file operation has been registered.

But before this patch can be applied we need to modify drivers that make the
assumption that a misc device file's private_data is initialized to NULL
because they didn't register a custom open file operation, so they don't rely
on this assumption anymore. FUSE uses private_data to store the fuse_conn and
errors out if this is not initialized to NULL at mount time.

Hence, we now set a file's private_data to NULL explicitly, to be independent
of whatever value the misc subsystem initializes it to by default.

[1] https://lkml.org/lkml/2014/12/4/939

Reported-by: Giedrius Statkevicius <giedriuswork@gmail.com>
Reported-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Tom Van Braeckel <tomvanbraeckel@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2015-03-19 15:29:22 +01:00
Christoph Hellwig
04b2fa9f8f fs: split generic and aio kiocb
Most callers in the kernel want to perform synchronous file I/O, but
still have to bloat the stack with a full struct kiocb.  Split out
the parts needed in filesystem code from those in the aio code, and
only allocate those needed to pass down argument on the stack.  The
aio code embedds the generic iocb in the one it allocates and can
easily get back to it by using container_of.

Also add a ->ki_complete method to struct kiocb, this is used to call
into the aio code and thus removes the dependency on aio for filesystems
impementing asynchronous operations.  It will also allow other callers
to substitute their own completion callback.

We also add a new ->ki_flags field to work around the nasty layering
violation recently introduced in commit 5e33f6 ("usb: gadget: ffs: add
eventfd notification about ffs events").

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-13 12:10:27 -04:00
Christoph Hellwig
9d5722b777 fuse: handle synchronous iocbs internally
Based on a patch from Maxim Patlasov <MPatlasov@parallels.com>.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-13 12:10:15 -04:00
Miklos Szeredi
aa991b3b26 fuse: set stolen page uptodate
Regular pipe buffers' ->steal method (generic_pipe_buf_steal()) doesn't set
PG_uptodate.

Don't warn on this condition, just set the uptodate flag.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: stable@vger.kernel.org
2015-02-26 11:45:47 +01:00
Miklos Szeredi
0d2783626a fuse: notify: don't move pages
fuse_try_move_page() is not prepared for replacing pages that have already
been read.

Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: stable@vger.kernel.org
2015-02-26 11:45:47 +01:00
David Howells
e36cb0b89c VFS: (Scripted) Convert S_ISLNK/DIR/REG(dentry->d_inode) to d_is_*(dentry)
Convert the following where appropriate:

 (1) S_ISLNK(dentry->d_inode) to d_is_symlink(dentry).

 (2) S_ISREG(dentry->d_inode) to d_is_reg(dentry).

 (3) S_ISDIR(dentry->d_inode) to d_is_dir(dentry).  This is actually more
     complicated than it appears as some calls should be converted to
     d_can_lookup() instead.  The difference is whether the directory in
     question is a real dir with a ->lookup op or whether it's a fake dir with
     a ->d_automount op.

In some circumstances, we can subsume checks for dentry->d_inode not being
NULL into this, provided we the code isn't in a filesystem that expects
d_inode to be NULL if the dirent really *is* negative (ie. if we're going to
use d_inode() rather than d_backing_inode() to get the inode pointer).

Note that the dentry type field may be set to something other than
DCACHE_MISS_TYPE when d_inode is NULL in the case of unionmount, where the VFS
manages the fall-through from a negative dentry to a lower layer.  In such a
case, the dentry type of the negative union dentry is set to the same as the
type of the lower dentry.

However, if you know d_inode is not NULL at the call site, then you can use
the d_is_xxx() functions even in a filesystem.

There is one further complication: a 0,0 chardev dentry may be labelled
DCACHE_WHITEOUT_TYPE rather than DCACHE_SPECIAL_TYPE.  Strictly, this was
intended for special directory entry types that don't have attached inodes.

The following perl+coccinelle script was used:

use strict;

my @callers;
open($fd, 'git grep -l \'S_IS[A-Z].*->d_inode\' |') ||
    die "Can't grep for S_ISDIR and co. callers";
@callers = <$fd>;
close($fd);
unless (@callers) {
    print "No matches\n";
    exit(0);
}

my @cocci = (
    '@@',
    'expression E;',
    '@@',
    '',
    '- S_ISLNK(E->d_inode->i_mode)',
    '+ d_is_symlink(E)',
    '',
    '@@',
    'expression E;',
    '@@',
    '',
    '- S_ISDIR(E->d_inode->i_mode)',
    '+ d_is_dir(E)',
    '',
    '@@',
    'expression E;',
    '@@',
    '',
    '- S_ISREG(E->d_inode->i_mode)',
    '+ d_is_reg(E)' );

my $coccifile = "tmp.sp.cocci";
open($fd, ">$coccifile") || die $coccifile;
print($fd "$_\n") || die $coccifile foreach (@cocci);
close($fd);

foreach my $file (@callers) {
    chomp $file;
    print "Processing ", $file, "\n";
    system("spatch", "--sp-file", $coccifile, $file, "--in-place", "--no-show-diff") == 0 ||
	die "spatch failed";
}

[AV: overlayfs parts skipped]

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-22 11:38:41 -05:00
Linus Torvalds
6bec003528 Merge branch 'for-3.20/bdi' of git://git.kernel.dk/linux-block
Pull backing device changes from Jens Axboe:
 "This contains a cleanup of how the backing device is handled, in
  preparation for a rework of the life time rules.  In this part, the
  most important change is to split the unrelated nommu mmap flags from
  it, but also removing a backing_dev_info pointer from the
  address_space (and inode), and a cleanup of other various minor bits.

  Christoph did all the work here, I just fixed an oops with pages that
  have a swap backing.  Arnd fixed a missing export, and Oleg killed the
  lustre backing_dev_info from staging.  Last patch was from Al,
  unexporting parts that are now no longer needed outside"

* 'for-3.20/bdi' of git://git.kernel.dk/linux-block:
  Make super_blocks and sb_lock static
  mtd: export new mtd_mmap_capabilities
  fs: make inode_to_bdi() handle NULL inode
  staging/lustre/llite: get rid of backing_dev_info
  fs: remove default_backing_dev_info
  fs: don't reassign dirty inodes to default_backing_dev_info
  nfs: don't call bdi_unregister
  ceph: remove call to bdi_unregister
  fs: remove mapping->backing_dev_info
  fs: export inode_to_bdi and use it in favor of mapping->backing_dev_info
  nilfs2: set up s_bdi like the generic mount_bdev code
  block_dev: get bdev inode bdi directly from the block device
  block_dev: only write bdev inode on close
  fs: introduce f_op->mmap_capabilities for nommu mmap support
  fs: kill BDI_CAP_SWAP_BACKED
  fs: deduplicate noop_backing_dev_info
2015-02-12 13:50:21 -08:00
Kirill A. Shutemov
d83a08db5b mm: drop vm_ops->remap_pages and generic_file_remap_pages() stub
Nobody uses it anymore.

[akpm@linux-foundation.org: fix filemap_xip.c]
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-10 14:30:30 -08:00
Christoph Hellwig
b83ae6d421 fs: remove mapping->backing_dev_info
Now that we never use the backing_dev_info pointer in struct address_space
we can simply remove it and save 4 to 8 bytes in every inode.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Reviewed-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-01-20 14:03:05 -07:00
Christoph Hellwig
de1414a654 fs: export inode_to_bdi and use it in favor of mapping->backing_dev_info
Now that we got rid of the bdi abuse on character devices we can always use
sb->s_bdi to get at the backing_dev_info for a file, except for the block
device special case.  Export inode_to_bdi and replace uses of
mapping->backing_dev_info with it to prepare for the removal of
mapping->backing_dev_info.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-01-20 14:03:04 -07:00
Miklos Szeredi
9759bd5189 fuse: add memory barrier to INIT
Theoretically we need to order setting of various fields in fc with
fc->initialized.

No known bug reports related to this yet.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2015-01-06 10:45:35 +01:00
Miklos Szeredi
21f621741a fuse: fix LOOKUP vs INIT compat handling
Analysis from Marc:

 "Commit 7078187a79 ("fuse: introduce fuse_simple_request() helper")
  from the above pull request triggers some EIO errors for me in some tests
  that rely on fuse

  Looking at the code changes and a bit of debugging info I think there's a
  general problem here that fuse_get_req checks and possibly waits for
  fc->initialized, and this was always called first.  But this commit
  changes the ordering and in many places fc->minor is now possibly used
  before fuse_get_req, and we can't be sure that fc has been initialized.
  In my case fuse_lookup_init sets req->out.args[0].size to the wrong size
  because fc->minor at that point is still 0, leading to the EIO error."

Fix by moving the compat adjustments into fuse_simple_request() to after
fuse_get_req().

This is also more readable than the original, since now compatibility is
handled in a single function instead of cluttering each operation.

Reported-by: Marc Dionne <marc.c.dionne@gmail.com>
Tested-by: Marc Dionne <marc.c.dionne@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Fixes: 7078187a79 ("fuse: introduce fuse_simple_request() helper")
2015-01-06 10:45:35 +01:00
Linus Torvalds
c103b21c20 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse update from Miklos Szeredi:
 "The first part makes sure we don't hold up umount with pending async
  requests.  In addition to being a cleanup, this is a small behavioral
  change (for the better) and unlikely to break anything.

  The second part prepares for a cleanup of the fuse device I/O code by
  adding a helper for simple request submission, with some savings in
  line numbers already realized"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: use file_inode() in fuse_file_fallocate()
  fuse: introduce fuse_simple_request() helper
  fuse: reduce max out args
  fuse: hold inode instead of path after release
  fuse: flush requests on umount
  fuse: don't wake up reserved req in fuse_conn_kill()
2014-12-17 09:41:32 -08:00
Miklos Szeredi
1c68271cf1 fuse: use file_inode() in fuse_file_fallocate()
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 10:04:51 +01:00
Miklos Szeredi
7078187a79 fuse: introduce fuse_simple_request() helper
The following pattern is repeated many times:

	req = fuse_get_req_nopages(fc);
	/* Initialize req->(in|out).args */
	fuse_request_send(fc, req);
	err = req->out.h.error;
	fuse_put_request(req);

Create a new replacement helper:

	/* Initialize args */
	err = fuse_simple_request(fc, &args);

In addition to reducing the code size, this will ease moving from the
complex arg-based to a simpler page-based I/O on the fuse device.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:05 +01:00