Commit Graph

107 Commits

Author SHA1 Message Date
Miklos Szeredi 4aa7c6346b vfs: add i_op->dentry_open()
Add a new inode operation i_op->dentry_open().  This is for stacked filesystems
that want to return a struct file from a different filesystem.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-10-24 00:14:35 +02:00
Jeff Layton c45198eda2 locks: move freeing of leases outside of i_lock
There was only one place where we still could free a file_lock while
holding the i_lock -- lease_modify. Add a new list_head argument to the
lm_change operation, pass in a private list when calling it, and fix
those callers to dispose of the list once the lock has been dropped.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2014-10-07 14:06:13 -04:00
Jeff Layton f82b4b6780 locks: move i_lock acquisition into generic_*_lease handlers
Now that we have a saner internal API for managing leases, we no longer
need to mandate that the inode->i_lock be held over most of the lease
code. Push it down into generic_add_lease and generic_delete_lease.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2014-10-07 14:06:13 -04:00
Jeff Layton e6f5c78930 locks: plumb a "priv" pointer into the setlease routines
In later patches, we're going to add a new lock_manager_operation to
finish setting up the lease while still holding the i_lock.  To do
this, we'll need to pass a little bit of info in the fcntl setlease
case (primarily an fasync structure). Plumb the extra pointer into
there in advance of that.

We declare this pointer as a void ** to make it clear that this is
private info, and that the caller isn't required to set this unless
the lm_setup specifically requires it.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2014-10-07 14:06:12 -04:00
Jeff Layton 2ece173e47 locks: update Locking documentation to clarify fl_release_private behavior
Acked-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
2014-08-14 10:08:20 -04:00
Al Viro 293bc9822f new methods: ->read_iter() and ->write_iter()
Beginning to introduce those.  Just the callers for now, and it's
clumsier than it'll eventually become; once we finish converting
aio_read and aio_write instances, the things will get nicer.

For now, these guys are in parallel to ->aio_read() and ->aio_write();
they take iocb and iov_iter, with everything in iov_iter already
validated.  File offset is passed in iocb->ki_pos, iov/nr_segs -
in iov_iter.

Main concerns in that series are stack footprint and ability to
split the damn thing cleanly.

[fix from Peter Ujfalusi <peter.ujfalusi@ti.com> folded]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-05-06 17:36:00 -04:00
Al Viro d8d3d94b80 pass iov_iter to ->direct_IO()
unmodified, for now

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-05-06 17:32:44 -04:00
Linus Torvalds 5166701b36 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
 "The first vfs pile, with deep apologies for being very late in this
  window.

  Assorted cleanups and fixes, plus a large preparatory part of iov_iter
  work.  There's a lot more of that, but it'll probably go into the next
  merge window - it *does* shape up nicely, removes a lot of
  boilerplate, gets rid of locking inconsistencie between aio_write and
  splice_write and I hope to get Kent's direct-io rewrite merged into
  the same queue, but some of the stuff after this point is having
  (mostly trivial) conflicts with the things already merged into
  mainline and with some I want more testing.

  This one passes LTP and xfstests without regressions, in addition to
  usual beating.  BTW, readahead02 in ltp syscalls testsuite has started
  giving failures since "mm/readahead.c: fix readahead failure for
  memoryless NUMA nodes and limit readahead pages" - might be a false
  positive, might be a real regression..."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
  missing bits of "splice: fix racy pipe->buffers uses"
  cifs: fix the race in cifs_writev()
  ceph_sync_{,direct_}write: fix an oops on ceph_osdc_new_request() failure
  kill generic_file_buffered_write()
  ocfs2_file_aio_write(): switch to generic_perform_write()
  ceph_aio_write(): switch to generic_perform_write()
  xfs_file_buffered_aio_write(): switch to generic_perform_write()
  export generic_perform_write(), start getting rid of generic_file_buffer_write()
  generic_file_direct_write(): get rid of ppos argument
  btrfs_file_aio_write(): get rid of ppos
  kill the 5th argument of generic_file_buffered_write()
  kill the 4th argument of __generic_file_aio_write()
  lustre: don't open-code kernel_recvmsg()
  ocfs2: don't open-code kernel_recvmsg()
  drbd: don't open-code kernel_recvmsg()
  constify blk_rq_map_user_iov() and friends
  lustre: switch to kernel_sendmsg()
  ocfs2: don't open-code kernel_sendmsg()
  take iov_iter stuff to mm/iov_iter.c
  process_vm_access: tidy up a bit
  ...
2014-04-12 14:49:50 -07:00
Kirill A. Shutemov 8c6e50b029 mm: introduce vm_ops->map_pages()
Here's new version of faultaround patchset.  It took a while to tune it
and collect performance data.

First patch adds new callback ->map_pages to vm_operations_struct.

->map_pages() is called when VM asks to map easy accessible pages.
Filesystem should find and map pages associated with offsets from
"pgoff" till "max_pgoff".  ->map_pages() is called with page table
locked and must not block.  If it's not possible to reach a page without
blocking, filesystem should skip it.  Filesystem should use do_set_pte()
to setup page table entry.  Pointer to entry associated with offset
"pgoff" is passed in "pte" field in vm_fault structure.  Pointers to
entries for other offsets should be calculated relative to "pte".

Currently VM use ->map_pages only on read page fault path.  We try to
map FAULT_AROUND_PAGES a time.  FAULT_AROUND_PAGES is 16 for now.
Performance data for different FAULT_AROUND_ORDER is below.

TODO:
 - implement ->map_pages() for shmem/tmpfs;
 - modify get_user_pages() to be able to use ->map_pages() and implement
   mmap(MAP_POPULATE|MAP_NONBLOCK) on top.

=========================================================================
Tested on 4-socket machine (120 threads) with 128GiB of RAM.

Few real-world workloads. The sweet spot for FAULT_AROUND_ORDER here is
somewhere between 3 and 5. Let's say 4 :)

Linux build (make -j60)
FAULT_AROUND_ORDER		Baseline	1		3		4		5		7		9
	minor-faults		283,301,572	247,151,987	212,215,789	204,772,882	199,568,944	194,703,779	193,381,485
	time, seconds		151.227629483	153.920996480	151.356125472	150.863792049	150.879207877	151.150764954	151.450962358
Linux rebuild (make -j60)
FAULT_AROUND_ORDER		Baseline	1		3		4		5		7		9
	minor-faults		5,396,854	4,148,444	2,855,286	2,577,282	2,361,957	2,169,573	2,112,643
	time, seconds		27.404543757	27.559725591	27.030057426	26.855045126	26.678618635	26.974523490	26.761320095
Git test suite (make -j60 test)
FAULT_AROUND_ORDER		Baseline	1		3		4		5		7		9
	minor-faults		129,591,823	99,200,751	66,106,718	57,606,410	51,510,808	45,776,813	44,085,515
	time, seconds		66.087215026	64.784546905	64.401156567	65.282708668	66.034016829	66.793780811	67.237810413

Two synthetic tests: access every word in file in sequential/random order.
It doesn't improve much after FAULT_AROUND_ORDER == 4.

Sequential access 16GiB file
FAULT_AROUND_ORDER		Baseline	1		3		4		5		7		9
 1 thread
	minor-faults		4,195,437	2,098,275	525,068		262,251		131,170		32,856		8,282
	time, seconds		7.250461742	6.461711074	5.493859139	5.488488147	5.707213983	5.898510832	5.109232856
 8 threads
	minor-faults		33,557,540	16,892,728	4,515,848	2,366,999	1,423,382	442,732		142,339
	time, seconds		16.649304881	9.312555263	6.612490639	6.394316732	6.669827501	6.75078944	6.371900528
 32 threads
	minor-faults		134,228,222	67,526,810	17,725,386	9,716,537	4,763,731	1,668,921	537,200
	time, seconds		49.164430543	29.712060103	12.938649729	10.175151004	11.840094583	9.594081325	9.928461797
 60 threads
	minor-faults		251,687,988	126,146,952	32,919,406	18,208,804	10,458,947	2,733,907	928,217
	time, seconds		86.260656897	49.626551828	22.335007632	17.608243696	16.523119035	16.339489186	16.326390902
 120 threads
	minor-faults		503,352,863	252,939,677	67,039,168	35,191,827	19,170,091	4,688,357	1,471,862
	time, seconds		124.589206333	79.757867787	39.508707872	32.167281632	29.972989292	28.729834575	28.042251622
Random access 1GiB file
 1 thread
	minor-faults		262,636		132,743		34,369		17,299		8,527		3,451		1,222
	time, seconds		15.351890914	16.613802482	16.569227308	15.179220992	16.557356122	16.578247824	15.365266994
 8 threads
	minor-faults		2,098,948	1,061,871	273,690		154,501		87,110		25,663		7,384
	time, seconds		15.040026343	15.096933500	14.474757288	14.289129964	14.411537468	14.296316837	14.395635804
 32 threads
	minor-faults		8,390,734	4,231,023	1,054,432	528,847		269,242		97,746		26,881
	time, seconds		20.430433109	21.585235358	22.115062928	14.872878951	14.880856305	14.883370649	14.821261690
 60 threads
	minor-faults		15,733,258	7,892,809	1,973,393	988,266		594,789		164,994		51,691
	time, seconds		26.577302548	25.692397770	18.728863715	20.153026398	21.619101933	17.745086260	17.613215273
 120 threads
	minor-faults		31,471,111	15,816,616	3,959,209	1,978,685	1,008,299	264,635		96,010
	time, seconds		41.835322703	40.459786095	36.085306105	35.313894834	35.814445675	36.552633793	34.289210594

Touch only one page in page table in 16GiB file
FAULT_AROUND_ORDER		Baseline	1		3		4		5		7		9
 1 thread
	minor-faults		8,372		8,324		8,270		8,260		8,249		8,239		8,237
	time, seconds		0.039892712	0.045369149	0.051846126	0.063681685	0.079095975	0.17652406	0.541213386
 8 threads
	minor-faults		65,731		65,681		65,628		65,620		65,608		65,599		65,596
	time, seconds		0.124159196	0.488600638	0.156854426	0.191901957	0.242631486	0.543569456	1.677303984
 32 threads
	minor-faults		262,388		262,341		262,285		262,276		262,266		262,257		263,183
	time, seconds		0.452421421	0.488600638	0.565020946	0.648229739	0.789850823	1.651584361	5.000361559
 60 threads
	minor-faults		491,822		491,792		491,723		491,711		491,701		491,691		491,825
	time, seconds		0.763288616	0.869620515	0.980727360	1.161732354	1.466915814	3.04041448	9.308612938
 120 threads
	minor-faults		983,466		983,655		983,366		983,372		983,363		984,083		984,164
	time, seconds		1.595846553	1.667902182	2.008959376	2.425380942	2.941368804	5.977807890	18.401846125

This patch (of 2):

Introduce new vm_ops callback ->map_pages() and uses it for mapping easy
accessible pages around fault address.

On read page fault, if filesystem provides ->map_pages(), we try to map up
to FAULT_AROUND_PAGES pages around page fault address in hope to reduce
number of minor page faults.

We call ->map_pages first and use ->fault() as fallback if page by the
offset is not ready to be mapped (cold page cache or something).

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ning Qu <quning@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07 16:35:52 -07:00
Al Viro c186afb4db switch ->is_partially_uptodate() to saner arguments
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-01 23:19:19 -04:00
Miklos Szeredi 520c8b1650 vfs: add renameat2 syscall
Add new renameat2 syscall, which is the same as renameat with an added
flags argument.

Pass flags to vfs_rename() and to i_op->rename() as well.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: J. Bruce Fields <bfields@redhat.com>
2014-04-01 17:08:42 +02:00
Stefan Weil 507da6a1f3 doc: Fix typo (acces_process_vm -> access_process_vm)
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-12-19 15:12:21 +01:00
Linus Torvalds 790eac5640 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull second set of VFS changes from Al Viro:
 "Assorted f_pos race fixes, making do_splice_direct() safe to call with
  i_mutex on parent, O_TMPFILE support, Jeff's locks.c series,
  ->d_hash/->d_compare calling conventions changes from Linus, misc
  stuff all over the place."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
  Document ->tmpfile()
  ext4: ->tmpfile() support
  vfs: export lseek_execute() to modules
  lseek_execute() doesn't need an inode passed to it
  block_dev: switch to fixed_size_llseek()
  cpqphp_sysfs: switch to fixed_size_llseek()
  tile-srom: switch to fixed_size_llseek()
  proc_powerpc: switch to fixed_size_llseek()
  ubi/cdev: switch to fixed_size_llseek()
  pci/proc: switch to fixed_size_llseek()
  isapnp: switch to fixed_size_llseek()
  lpfc: switch to fixed_size_llseek()
  locks: give the blocked_hash its own spinlock
  locks: add a new "lm_owner_key" lock operation
  locks: turn the blocked_list into a hashtable
  locks: convert fl_link to a hlist_node
  locks: avoid taking global lock if possible when waking up blocked waiters
  locks: protect most of the file_lock handling with i_lock
  locks: encapsulate the fl_link list handling
  locks: make "added" in __posix_lock_file a bool
  ...
2013-07-03 09:10:19 -07:00
Al Viro 48bde8d362 Document ->tmpfile()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-07-03 16:23:29 +04:00
Linus Torvalds 9e239bb939 Lots of bug fixes, cleanups and optimizations. In the bug fixes
category, of note is a fix for on-line resizing file systems where the
 block size is smaller than the page size (i.e., file systems 1k blocks
 on x86, or more interestingly file systems with 4k blocks on Power or
 ia64 systems.)
 
 In the cleanup category, the ext4's punch hole implementation was
 significantly improved by Lukas Czerner, and now supports bigalloc
 file systems.  In addition, Jan Kara significantly cleaned up the
 write submission code path.  We also improved error checking and added
 a few sanity checks.
 
 In the optimizations category, two major optimizations deserve
 mention.  The first is that ext4_writepages() is now used for
 nodelalloc and ext3 compatibility mode.  This allows writes to be
 submitted much more efficiently as a single bio request, instead of
 being sent as individual 4k writes into the block layer (which then
 relied on the elevator code to coalesce the requests in the block
 queue).  Secondly, the extent cache shrink mechanism, which was
 introduce in 3.9, no longer has a scalability bottleneck caused by the
 i_es_lru spinlock.  Other optimizations include some changes to reduce
 CPU usage and to avoid issuing empty commits unnecessarily.
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 update from Ted Ts'o:
 "Lots of bug fixes, cleanups and optimizations.  In the bug fixes
  category, of note is a fix for on-line resizing file systems where the
  block size is smaller than the page size (i.e., file systems 1k blocks
  on x86, or more interestingly file systems with 4k blocks on Power or
  ia64 systems.)

  In the cleanup category, the ext4's punch hole implementation was
  significantly improved by Lukas Czerner, and now supports bigalloc
  file systems.  In addition, Jan Kara significantly cleaned up the
  write submission code path.  We also improved error checking and added
  a few sanity checks.

  In the optimizations category, two major optimizations deserve
  mention.  The first is that ext4_writepages() is now used for
  nodelalloc and ext3 compatibility mode.  This allows writes to be
  submitted much more efficiently as a single bio request, instead of
  being sent as individual 4k writes into the block layer (which then
  relied on the elevator code to coalesce the requests in the block
  queue).  Secondly, the extent cache shrink mechanism, which was
  introduce in 3.9, no longer has a scalability bottleneck caused by the
  i_es_lru spinlock.  Other optimizations include some changes to reduce
  CPU usage and to avoid issuing empty commits unnecessarily."

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (86 commits)
  ext4: optimize starting extent in ext4_ext_rm_leaf()
  jbd2: invalidate handle if jbd2_journal_restart() fails
  ext4: translate flag bits to strings in tracepoints
  ext4: fix up error handling for mpage_map_and_submit_extent()
  jbd2: fix theoretical race in jbd2__journal_restart
  ext4: only zero partial blocks in ext4_zero_partial_blocks()
  ext4: check error return from ext4_write_inline_data_end()
  ext4: delete unnecessary C statements
  ext3,ext4: don't mess with dir_file->f_pos in htree_dirblock_to_tree()
  jbd2: move superblock checksum calculation to jbd2_write_superblock()
  ext4: pass inode pointer instead of file pointer to punch hole
  ext4: improve free space calculation for inline_data
  ext4: reduce object size when !CONFIG_PRINTK
  ext4: improve extent cache shrink mechanism to avoid to burn CPU time
  ext4: implement error handling of ext4_mb_new_preallocation()
  ext4: fix corruption when online resizing a fs with 1K block size
  ext4: delete unused variables
  ext4: return FIEMAP_EXTENT_UNKNOWN for delalloc extents
  jbd2: remove debug dependency on debug_fs and update Kconfig help text
  jbd2: use a single printk for jbd_debug()
  ...
2013-07-02 09:39:34 -07:00
Jeff Layton 7b2296afb3 locks: give the blocked_hash its own spinlock
There's no reason we have to protect the blocked_hash and file_lock_list
with the same spinlock. With the tests I have, breaking it in two gives
a barely measurable performance benefit, but it seems reasonable to make
this locking as granular as possible.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29 12:57:46 +04:00
Jeff Layton 3999e49364 locks: add a new "lm_owner_key" lock operation
Currently, the hashing that the locking code uses to add these values
to the blocked_hash is simply calculated using fl_owner field. That's
valid in most cases except for server-side lockd, which validates the
owner of a lock based on fl_owner and fl_pid.

In the case where you have a small number of NFS clients doing a lot
of locking between different processes, you could end up with all
the blocked requests sitting in a very small number of hash buckets.

Add a new lm_owner_key operation to the lock_manager_operations that
will generate an unsigned long to use as the key in the hashtable.
That function is only implemented for server-side lockd, and simply
XORs the fl_owner and fl_pid.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29 12:57:45 +04:00
Jeff Layton 1c8c601a8c locks: protect most of the file_lock handling with i_lock
Having a global lock that protects all of this code is a clear
scalability problem. Instead of doing that, move most of the code to be
protected by the i_lock instead. The exceptions are the global lists
that the ->fl_link sits on, and the ->fl_block list.

->fl_link is what connects these structures to the
global lists, so we must ensure that we hold those locks when iterating
over or updating these lists.

Furthermore, sound deadlock detection requires that we hold the
blocked_list state steady while checking for loops. We also must ensure
that the search and update to the list are atomic.

For the checking and insertion side of the blocked_list, push the
acquisition of the global lock into __posix_lock_file and ensure that
checking and update of the  blocked_list is done without dropping the
lock in between.

On the removal side, when waking up blocked lock waiters, take the
global lock before walking the blocked list and dequeue the waiters from
the global list prior to removal from the fl_block list.

With this, deadlock detection should be race free while we minimize
excessive file_lock_lock thrashing.

Finally, in order to avoid a lock inversion problem when handling
/proc/locks output we must ensure that manipulations of the fl_block
list are also protected by the file_lock_lock.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29 12:57:42 +04:00
Linus Torvalds da53be12bb Don't pass inode to ->d_hash() and ->d_compare()
Instances either don't look at it at all (the majority of cases) or
only want it to find the superblock (which can be had as dentry->d_sb).
A few cases that want more are actually safe with dentry->d_inode -
the only precaution needed is the check that it hadn't been replaced with
NULL by rmdir() or by overwriting rename(), which case should be simply
treated as cache miss.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29 12:57:36 +04:00
Al Viro 2233f31aad [readdir] ->readdir() is gone
everything's converted to ->iterate()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29 12:57:04 +04:00
Lukas Czerner d47992f86b mm: change invalidatepage prototype to accept length
Currently there is no way to truncate partial page where the end
truncate point is not at the end of the page. This is because it was not
needed and the functionality was enough for file system truncate
operation to work properly. However more file systems now support punch
hole feature and it can benefit from mm supporting truncating page just
up to the certain point.

Specifically, with this functionality truncate_inode_pages_range() can
be changed so it supports truncating partial page at the end of the
range (currently it will BUG_ON() if 'end' is not at the end of the
page).

This commit changes the invalidatepage() address space operation
prototype to accept range to be invalidated and update all the instances
for it.

We also change the block_invalidatepage() in the same way and actually
make a use of the new length argument implementing range invalidation.

Actual file system implementations will follow except the file systems
where the changes are really simple and should not change the behaviour
in any way .Implementation for truncate_page_range() which will be able
to accept page unaligned ranges will follow as well.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Hugh Dickins <hughd@google.com>
2013-05-21 23:17:23 -04:00
Jeff Layton ecf3d1f1aa vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op
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>
2013-02-26 02:46:09 -05:00
Marco Stornelli b9f61c3c0c documentation: drop vmtruncate
Removed vmtruncate

Signed-off-by: Marco Stornelli <marco.stornelli@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20 18:47:08 -05:00
Artem Bityutskiy 34e5053fbe Documentation: get rid of write_super
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>
2012-08-04 01:25:20 +04:00
Linus Torvalds a0e881b7c1 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull second vfs pile from Al Viro:
 "The stuff in there: fsfreeze deadlock fixes by Jan (essentially, the
  deadlock reproduced by xfstests 068), symlink and hardlink restriction
  patches, plus assorted cleanups and fixes.

  Note that another fsfreeze deadlock (emergency thaw one) is *not*
  dealt with - the series by Fernando conflicts a lot with Jan's, breaks
  userland ABI (FIFREEZE semantics gets changed) and trades the deadlock
  for massive vfsmount leak; this is going to be handled next cycle.
  There probably will be another pull request, but that stuff won't be
  in it."

Fix up trivial conflicts due to unrelated changes next to each other in
drivers/{staging/gdm72xx/usb_boot.c, usb/gadget/storage_common.c}

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (54 commits)
  delousing target_core_file a bit
  Documentation: Correct s_umount state for freeze_fs/unfreeze_fs
  fs: Remove old freezing mechanism
  ext2: Implement freezing
  btrfs: Convert to new freezing mechanism
  nilfs2: Convert to new freezing mechanism
  ntfs: Convert to new freezing mechanism
  fuse: Convert to new freezing mechanism
  gfs2: Convert to new freezing mechanism
  ocfs2: Convert to new freezing mechanism
  xfs: Convert to new freezing code
  ext4: Convert to new freezing mechanism
  fs: Protect write paths by sb_start_write - sb_end_write
  fs: Skip atime update on frozen filesystem
  fs: Add freezing handling to mnt_want_write() / mnt_drop_write()
  fs: Improve filesystem freezing handling
  switch the protection of percpu_counter list to spinlock
  nfsd: Push mnt_want_write() outside of i_mutex
  btrfs: Push mnt_want_write() outside of i_mutex
  fat: Push mnt_want_write() outside of i_mutex
  ...
2012-08-01 10:26:23 -07:00
J. Bruce Fields 068535f1fe locks: remove unused lm_release_private
In commit 3b6e2723f3 ("locks: prevent side-effects of
locks_release_private before file_lock is initialized") we removed the
last user of lm_release_private without removing the field itself.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-01 09:01:46 -07:00
Mel Gorman 62c230bc17 mm: add support for a filesystem to activate swap files and use direct_IO for writing swap pages
Currently swapfiles are managed entirely by the core VM by using ->bmap to
allocate space and write to the blocks directly.  This effectively ensures
that the underlying blocks are allocated and avoids the need for the swap
subsystem to locate what physical blocks store offsets within a file.

If the swap subsystem is to use the filesystem information to locate the
blocks, it is critical that information such as block groups, block
bitmaps and the block descriptor table that map the swap file were
resident in memory.  This patch adds address_space_operations that the VM
can call when activating or deactivating swap backed by a file.

  int swap_activate(struct file *);
  int swap_deactivate(struct file *);

The ->swap_activate() method is used to communicate to the file that the
VM relies on it, and the address_space should take adequate measures such
as reserving space in the underlying device, reserving memory for mempools
and pinning information such as the block descriptor table in memory.  The
->swap_deactivate() method is called on sys_swapoff() if ->swap_activate()
returned success.

After a successful swapfile ->swap_activate, the swapfile is marked
SWP_FILE and swapper_space.a_ops will proxy to
sis->swap_file->f_mappings->a_ops using ->direct_io to write swapcache
pages and ->readpage to read.

It is perfectly possible that direct_IO be used to read the swap pages but
it is an unnecessary complication.  Similarly, it is possible that
->writepage be used instead of direct_io to write the pages but filesystem
developers have stated that calling writepage from the VM is undesirable
for a variety of reasons and using direct_IO opens up the possibility of
writing back batches of swap pages in the future.

[a.p.zijlstra@chello.nl: Original patch]
Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric B Munson <emunson@mgebm.net>
Cc: Eric Paris <eparis@redhat.com>
Cc: James Morris <jmorris@namei.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: Neil Brown <neilb@suse.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Xiaotian Feng <dfeng@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 18:42:47 -07:00
Valerie Aurora 06fd516c1a Documentation: Correct s_umount state for freeze_fs/unfreeze_fs
freeze_fs/unfreeze_fs ops are called with s_umount held for write, not read.

Signed-off-by: Valerie Aurora <val@vaaconsulting.com>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-31 09:45:55 +04:00
Al Viro ebfc3b49a7 don't pass nameidata to ->create()
boolean "does it have to be exclusive?" flag is passed instead;
Local filesystem should just ignore it - the object is guaranteed
not to be there yet.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:34:47 +04:00
Al Viro 00cd8dd3bf stop passing nameidata to ->lookup()
Just the flags; only NFS cares even about that, but there are
legitimate uses for such argument.  And getting rid of that
completely would require splitting ->lookup() into a couple
of methods (at least), so let's leave that alone for now...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:34:32 +04:00
Al Viro 0b728e1911 stop passing nameidata * to ->d_revalidate()
Just the lookup flags.  Die, bastard, die...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:34:14 +04:00
Al Viro 30d9049474 kill struct opendata
Just pass struct file *.  Methods are happier that way...
There's no need to return struct file * from finish_open() now,
so let it return int.  Next: saner prototypes for parts in
namei.c

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:33:39 +04:00
Al Viro d95852777b make ->atomic_open() return int
Change of calling conventions:
old		new
NULL		1
file		0
ERR_PTR(-ve)	-ve

Caller *knows* that struct file *; no need to return it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:33:35 +04:00
Al Viro 47237687d7 ->atomic_open() prototype change - pass int * instead of bool *
... and let finish_open() report having opened the file via that sucker.
Next step: don't modify od->filp at all.

[AV: FILE_CREATE was already used by cifs; Miklos' fix folded]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:33:31 +04:00
Miklos Szeredi d18e9008c3 vfs: add i_op->atomic_open()
Add a new inode operation which is called on the last component of an open.
Using this the filesystem can look up, possibly create and open the file in one
atomic operation.  If it cannot perform this (e.g. the file type turned out to
be wrong) it may signal this by returning NULL instead of an open struct file
pointer.

i_op->atomic_open() is only called if the last component is negative or needs
lookup.  Handling cached positive dentries here doesn't add much value: these
can be opened using f_op->open().  If the cached file turns out to be invalid,
the open can be retried, this time using ->atomic_open() with a fresh dentry.

For now leave the old way of using open intents in lookup and revalidate in
place.  This will be removed once all the users are converted.

David Howells noticed that if ->atomic_open() opens the file but does not create
it, handle_truncate() will be called on it even if it is not a regular file.
Fix this by checking the file type in this case too.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:33:04 +04:00
Linus Torvalds 1193755ac6 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs changes from Al Viro.
 "A lot of misc stuff.  The obvious groups:
   * Miklos' atomic_open series; kills the damn abuse of
     ->d_revalidate() by NFS, which was the major stumbling block for
     all work in that area.
   * ripping security_file_mmap() and dealing with deadlocks in the
     area; sanitizing the neighborhood of vm_mmap()/vm_munmap() in
     general.
   * ->encode_fh() switched to saner API; insane fake dentry in
     mm/cleancache.c gone.
   * assorted annotations in fs (endianness, __user)
   * parts of Artem's ->s_dirty work (jff2 and reiserfs parts)
   * ->update_time() work from Josef.
   * other bits and pieces all over the place.

  Normally it would've been in two or three pull requests, but
  signal.git stuff had eaten a lot of time during this cycle ;-/"

Fix up trivial conflicts in Documentation/filesystems/vfs.txt (the
'truncate_range' inode method was removed by the VM changes, the VFS
update adds an 'update_time()' method), and in fs/btrfs/ulist.[ch] (due
to sparse fix added twice, with other changes nearby).

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (95 commits)
  nfs: don't open in ->d_revalidate
  vfs: retry last component if opening stale dentry
  vfs: nameidata_to_filp(): don't throw away file on error
  vfs: nameidata_to_filp(): inline __dentry_open()
  vfs: do_dentry_open(): don't put filp
  vfs: split __dentry_open()
  vfs: do_last() common post lookup
  vfs: do_last(): add audit_inode before open
  vfs: do_last(): only return EISDIR for O_CREAT
  vfs: do_last(): check LOOKUP_DIRECTORY
  vfs: do_last(): make ENOENT exit RCU safe
  vfs: make follow_link check RCU safe
  vfs: do_last(): use inode variable
  vfs: do_last(): inline walk_component()
  vfs: do_last(): make exit RCU safe
  vfs: split do_lookup()
  Btrfs: move over to use ->update_time
  fs: introduce inode operation ->update_time
  reiserfs: get rid of resierfs_sync_super
  reiserfs: mark the superblock as dirty a bit later
  ...
2012-06-01 10:34:35 -07:00
Josef Bacik c3b2da3148 fs: introduce inode operation ->update_time
Btrfs has to make sure we have space to allocate new blocks in order to modify
the inode, so updating time can fail.  We've gotten around this by having our
own file_update_time but this is kind of a pain, and Christoph has indicated he
would like to make xfs do something different with atime updates.  So introduce
->update_time, where we will deal with i_version an a/m/c time updates and
indicate which changes need to be made.  The normal version just does what it
has always done, updates the time and marks the inode dirty, and then
filesystems can choose to do something different.

I've gone through all of the users of file_update_time and made them check for
errors with the exception of the fault code since it's complicated and I wasn't
quite sure what to do there, also Jan is going to be pushing the file time
updates into page_mkwrite for those who have it so that should satisfy btrfs and
make it not a big deal to check the file_update_time() return code in the
generic fault path. Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
2012-06-01 12:07:25 -04:00
Hugh Dickins 17cf28afea mm/fs: remove truncate_range
Remove vmtruncate_range(), and remove the truncate_range method from
struct inode_operations: only tmpfs ever supported it, and tmpfs has now
converted over to using the fallocate method of file_operations.

Update Documentation accordingly, adding (setlease and) fallocate lines.
And while we're in mm.h, remove duplicate declarations of shmem_lock() and
shmem_file_setup(): everyone is now using the ones in shmem_fs.h.

Based-on-patch-by: Cong Wang <amwang@redhat.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Cong Wang <amwang@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-29 16:22:23 -07:00
Al Viro 34c80b1d93 vfs: switch ->show_options() to struct dentry *
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-06 23:19:54 -05:00
Al Viro 1a67aafb5f switch ->mknod() to umode_t
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:54:54 -05:00
Al Viro 4acdaf27eb switch ->create() to umode_t
vfs_create() ignores everything outside of 16bit subset of its
mode argument; switching it to umode_t is obviously equivalent
and it's the only caller of the method

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:54:53 -05:00
Al Viro 18bb1db3e7 switch vfs_mkdir() and ->mkdir() to umode_t
vfs_mkdir() gets int, but immediately drops everything that might not
fit into umode_t and that's the only caller of ->mkdir()...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:54:53 -05:00
Sage Weil f0023bc617 vfs: add d_prune dentry operation
This adds a d_prune dentry operation that is called by the VFS prior to
pruning (i.e. unhashing and killing) a hashed dentry from the dcache.
Wrap dentry_lru_del() and use the new _prune() helper in the cases where we
are about to unhash and kill the dentry.

This will be used by Ceph to maintain a flag indicating whether the
complete contents of a directory are contained in the dcache, allowing it
to satisfy lookups and readdir without addition server communication.

Renumber a few DCACHE_* #defines to group DCACHE_OP_PRUNE with the other
DCACHE_OP_ bits.

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2011-11-02 12:53:43 +01:00
Linus Torvalds 2dad3206db Merge branch 'for-3.1' of git://linux-nfs.org/~bfields/linux
* 'for-3.1' of git://linux-nfs.org/~bfields/linux:
  nfsd: don't break lease on CLAIM_DELEGATE_CUR
  locks: rename lock-manager ops
  nfsd4: update nfsv4.1 implementation notes
  nfsd: turn on reply cache for NFSv4
  nfsd4: call nfsd4_release_compoundargs from pc_release
  nfsd41: Deny new lock before RECLAIM_COMPLETE done
  fs: locks: remove init_once
  nfsd41: check the size of request
  nfsd41: error out when client sets maxreq_sz or maxresp_sz too small
  nfsd4: fix file leak on open_downgrade
  nfsd4: remember to put RW access on stateid destruction
  NFSD: Added TEST_STATEID operation
  NFSD: added FREE_STATEID operation
  svcrpc: fix list-corrupting race on nfsd shutdown
  rpc: allow autoloading of gss mechanisms
  svcauth_unix.c: quiet sparse noise
  svcsock.c: include sunrpc.h to quiet sparse noise
  nfsd: Remove deprecated nfsctl system call and related code.
  NFSD: allow OP_DESTROY_CLIENTID to be only op in COMPOUND

Fix up trivial conflicts in Documentation/feature-removal-schedule.txt
2011-07-25 22:49:19 -07:00
Christoph Hellwig 4e34e719e4 fs: take the ACL checks to common code
Replace the ->check_acl method with a ->get_acl method that simply reads an
ACL from disk after having a cache miss.  This means we can replace the ACL
checking boilerplate code with a single implementation in namei.c.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-25 14:30:23 -04:00
Josef Bacik 02c24a8218 fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers
Btrfs needs to be able to control how filemap_write_and_wait_range() is called
in fsync to make it less of a painful operation, so push down taking i_mutex and
the calling of filemap_write_and_wait() down into the ->fsync() handlers.  Some
file systems can drop taking the i_mutex altogether it seems, like ext3 and
ocfs2.  For correctness sake I just pushed everything down in all cases to make
sure that we keep the current behavior the same for everybody, and then each
individual fs maintainer can make up their mind about what to do from there.
Thanks,

Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 20:47:59 -04:00
J. Bruce Fields 8fb47a4fbf locks: rename lock-manager ops
Both the filesystem and the lock manager can associate operations with a
lock.  Confusingly, one of them (fl_release_private) actually has the
same name in both operation structures.

It would save some confusion to give the lock-manager ops different
names.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2011-07-20 20:23:19 -04:00
Al Viro 7e40145eb1 ->permission() sanitizing: don't pass flags to ->check_acl()
not used in the instances anymore.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 01:43:21 -04:00
Christoph Hellwig aa38572954 fs: pass exact type of data dirties to ->dirty_inode
Tell the filesystem if we just updated timestamp (I_DIRTY_SYNC) or
anything else, so that the filesystem can track internally if it
needs to push out a transaction for fdatasync or not.

This is just the prototype change with no user for it yet.  I plan
to push large XFS changes for the next merge window, and getting
this trivial infrastructure in this window would help a lot to avoid
tree interdependencies.

Also remove incorrect comments that ->dirty_inode can't block.  That
has been changed a long time ago, and many implementations rely on it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-05-27 07:04:40 -04:00
Dave Chinner f283c86afe fs: remove inode_lock from iput_final and prune_icache
Now that inode state changes are protected by the inode->i_lock and
the inode LRU manipulations by the inode_lru_lock, we can remove the
inode_lock from prune_icache and the initial part of iput_final().

instead of using the inode_lock to protect the inode during
iput_final, use the inode->i_lock instead. This protects the inode
against new references being taken while we change the inode state
to I_FREEING, as well as preventing prune_icache from grabbing the
inode while we are manipulating it. Hence we no longer need the
inode_lock in iput_final prior to setting I_FREEING on the inode.

For prune_icache, we no longer need the inode_lock to protect the
LRU list, and the inodes themselves are protected against freeing
races by the inode->i_lock. Hence we can lift the inode_lock from
prune_icache as well.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-03-24 21:16:32 -04:00