Commit Graph

102 Commits

Author SHA1 Message Date
Andreas Gruenbacher 0ebbe4f974 gfs2: Fix the gfs2_invalidatepage description
The comment incorrectly states that the function always returns 0.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2018-12-11 17:50:35 +01:00
Andreas Gruenbacher 977767a7e1 gfs2: Clean up gfs2_is_{ordered,writeback}
The gfs2_is_ordered and gfs2_is_writeback checks are weird in that they
implicitly check for !gfs2_is_jdata.  This makes understanding how to
use those functions correctly a challenge.  Clean this up by making
gfs2_is_ordered and gfs2_is_writeback take a super block instead of an
inode and by removing the implicit !gfs2_is_jdata checks.  Update the
callers accordingly.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2018-12-11 17:50:35 +01:00
Matthew Wilcox 10bbd23585 pagevec: Use xa_mark_t
Removes sparse warnings.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:39 -04:00
Andreas Gruenbacher f95cbb44ab gfs2: use iomap_readpage for blocksize == PAGE_SIZE
We only use iomap_readpage for pages that don't have buffer heads
attached yet: iomap_readpage would otherwise read pages from disk that
are marked buffer_uptodate() but not PageUptodate().  Those pages may
actually contain data more recent than what's on disk.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Bob Peterson <rpeterso@redhat.com>
2018-07-25 00:08:49 +02:00
Andreas Gruenbacher 025d0e7f73 gfs2: Remove gfs2_write_{begin,end}
Now that generic_file_write_iter is no longer used, there are no
remaining users of these address space operations.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Bob Peterson <rpeterso@redhat.com>
2018-07-02 16:27:38 +01:00
Andreas Gruenbacher 967bcc91b0 gfs2: iomap direct I/O support
The page unmapping previously done in gfs2_direct_IO is now done
generically in iomap_dio_rw.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Bob Peterson <rpeterso@redhat.com>
2018-07-02 16:27:32 +01:00
Andreas Gruenbacher 64bc06bb32 gfs2: iomap buffered write support
With the traditional page-based writes, blocks are allocated separately
for each page written to.  With iomap writes, we can allocate a lot more
blocks at once, with a fraction of the allocation overhead for each
page.

Split calculating the number of blocks that can be allocated at a given
position (gfs2_alloc_size) off from gfs2_iomap_alloc: that size
determines the number of blocks to allocate and reserve in the journal.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Bob Peterson <rpeterso@redhat.com>
2018-07-02 16:27:17 +01:00
Andreas Gruenbacher 845802b112 gfs2: Remove ordered write mode handling from gfs2_trans_add_data
In journaled data mode, we need to add each buffer head to the current
transaction.  In ordered write mode, we only need to add the inode to
the ordered inode list.  So far, both cases are handled in
gfs2_trans_add_data.  This makes the code look misleading and is
inefficient for small block sizes as well.  Handle both cases separately
instead.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-06-04 07:50:16 -05:00
Andreas Gruenbacher d6382a3505 gfs2: gfs2_stuffed_write_end cleanup
First, change the sanity check in gfs2_stuffed_write_end to check for
the actual write size instead of the requested write size.

Second, use the existing teardown code in gfs2_write_end instead of
duplicating it in gfs2_stuffed_write_end.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-06-04 07:45:53 -05:00
Andreas Gruenbacher 7b5747f43f GFS2: Fix allocation error bug with recursive rgrp glocking
Before this patch function gfs2_write_begin, upon discovering an
error, called gfs2_trim_blocks while the rgrp glock was still held.
That's because gfs2_inplace_release is not called until later.
This patch reorganizes the logic a bit so gfs2_inplace_release
is called to release the lock prior to the call to gfs2_trim_blocks,
thus preventing the glock recursion.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-06-04 07:33:17 -05:00
Bob Peterson b9e03f1861 GFS2: Only set PageChecked for jdata pages
Before this patch, GFS2 was setting the PageChecked flag for ordered
write pages. This is unnecessary. The ext3 file system only does it
for jdata, and it's only used in jdata circumstances. It only muddies
the already murky waters of writing pages in the aops.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-03-08 09:26:20 -07:00
Bob Peterson 805c090750 GFS2: Log the reason for log flushes in every log header
This patch just adds the capability for GFS2 to track which function
called gfs2_log_flush. This should make it easier to diagnose
problems based on the sequence of events found in the journals.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
2018-01-23 07:39:20 -07:00
Bob Peterson c1696fb85d GFS2: Introduce new gfs2_log_header_v2
This patch adds a new structure called gfs2_log_header_v2 which is used
to store expanded fields into previously unused areas of the log headers
(i.e., this change is backwards compatible).  Some of these are used for
debug purposes so we can backtrack when problems occur.  Others are
reserved for future expansion.

This patch is based on a prototype from Steve Whitehouse.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2018-01-23 07:38:53 -07:00
Andreas Gruenbacher 88b65ce5fd gfs2: Minor gfs2_page_add_databufs cleanup
The to parameter of gfs2_page_add_databufs is passed inconsistently:
once as from + len, once as from + len - 1.  Just pass len instead.

In addition, once we're past the end, we can immediately break out of
the loop.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-01-18 14:18:55 -07:00
Andreas Gruenbacher 235628c5c7 gfs2: Add gfs2_max_stuffed_size
Add a small inline function for computing the maximum size of a stuffed
inode instead of open coding that in several places throughout the code.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-01-18 14:18:53 -07:00
Andreas Gruenbacher 9db115a0e3 gfs2: Typo fixes
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-01-18 14:18:49 -07:00
Andreas Gruenbacher 9aa0159327 gfs2: Remove unused gfs2_write_jdata_pagevec parameter
As a follow-up to commit d2bc5b3c67, remove the end parameter which is
now unused.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2017-11-27 10:54:55 -06:00
Mel Gorman 8667982014 mm, pagevec: remove cold parameter for pagevecs
Every pagevec_init user claims the pages being released are hot even in
cases where it is unlikely the pages are hot.  As no one cares about the
hotness of pages being released to the allocator, just ditch the
parameter.

No performance impact is expected as the overhead is marginal.  The
parameter is removed simply because it is a bit stupid to have a useless
parameter copied everywhere.

Link: http://lkml.kernel.org/r/20171018075952.10627-6-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15 18:21:06 -08:00
Jan Kara 67fd707f46 mm: remove nr_pages argument from pagevec_lookup_{,range}_tag()
All users of pagevec_lookup() and pagevec_lookup_range() now pass
PAGEVEC_SIZE as a desired number of pages.  Just drop the argument.

Link: http://lkml.kernel.org/r/20171009151359.31984-15-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15 18:21:04 -08:00
Jan Kara d2bc5b3c67 gfs2: use pagevec_lookup_range_tag()
We want only pages from given range in gfs2_write_cache_jdata().  Use
pagevec_lookup_range_tag() instead of pagevec_lookup_tag() and remove
unnecessary code.

Link: http://lkml.kernel.org/r/20171009151359.31984-9-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15 18:21:04 -08:00
Abhi Das b066a4eebd gfs2: forcibly flush ail to relieve memory pressure
On systems with low memory, it is possible for gfs2 to infinitely
loop in balance_dirty_pages() under heavy IO (creating sparse files).

balance_dirty_pages() attempts to write out the dirty pages via
gfs2_writepages() but none are found because these dirty pages are
being used by the journaling code in the ail. Normally, the journal
has an upper threshold which when hit triggers an automatic flush
of the ail. But this threshold can be higher than the number of
allowable dirty pages and result in the ail never being flushed.

This patch forces an ail flush when gfs2_writepages() fails to write
anything. This is a good indication that the ail might be holding
some dirty pages.

Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2017-08-10 10:51:03 -05:00
Linus Torvalds 9763dd6f81 We've got eight GFS2 patches for this merge window:
1. Andy Price submitted a patch to make gfs2_write_full_page a
    static function.
 2. Dan Carpenter submitted a patch to fix a ERR_PTR thinko.
 
 I've also got a few patches, three of which fix bugs related to
 deleting very large files, which cause GFS2 to run out of
 journal space:
 
 3. The first one prevents GFS2 delete operation from requesting too
    much journal space.
 4. The second one fixes a problem whereby GFS2 can hang because it
    wasn't taking journal space demand into its calculations.
 5. The third one wakes up IO waiters when a flush is done to restart
    processes stuck waiting for journal space to become available.
 
 The other three patches are a performance improvement related to
 spin_lock contention between multiple writers:
 
 6. The "tr_touched" variable was switched to a flag to be more atomic
    and eliminate the possibility of some races.
 7. Function meta_lo_add was moved inline with its only caller to make
    the code more readable and efficient.
 8. Contention on the gfs2_log_lock spinlock was greatly reduced by
    avoiding the lock altogether in cases where we don't really need
    it: buffers that already appear in the appropriate metadata list
    for the journal. Many thanks to Steve Whitehouse for the ideas and
    principles behind these patches.
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Merge tag 'gfs2-4.11.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2

Pull GFS2 updates from Robert Peterson:
 "We've got eight GFS2 patches for this merge window:

   - Andy Price submitted a patch to make gfs2_write_full_page a static
     function.

   - Dan Carpenter submitted a patch to fix a ERR_PTR thinko.

  Three patches fix bugs related to deleting very large files, which
  cause GFS2 to run out of journal space:

   - The first one prevents GFS2 delete operation from requesting too
     much journal space.

   - The second one fixes a problem whereby GFS2 can hang because it
     wasn't taking journal space demand into its calculations.

   - The third one wakes up IO waiters when a flush is done to restart
     processes stuck waiting for journal space to become available.

  The final three patches are a performance improvement related to
  spin_lock contention between multiple writers:

   - The "tr_touched" variable was switched to a flag to be more atomic
     and eliminate the possibility of some races.

   - Function meta_lo_add was moved inline with its only caller to make
     the code more readable and efficient.

   - Contention on the gfs2_log_lock spinlock was greatly reduced by
     avoiding the lock altogether in cases where we don't really need
     it: buffers that already appear in the appropriate metadata list
     for the journal. Many thanks to Steve Whitehouse for the ideas and
     principles behind these patches"

* tag 'gfs2-4.11.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: Make gfs2_write_full_page static
  GFS2: Reduce contention on gfs2_log_lock
  GFS2: Inline function meta_lo_add
  GFS2: Switch tr_touched to flag in transaction
  GFS2: Wake up io waiters whenever a flush is done
  GFS2: Made logd daemon take into account log demand
  GFS2: Limit number of transaction blocks requested for truncates
  GFS2: Fix reference to ERR_PTR in gfs2_glock_iter_next
2017-02-21 07:46:34 -08:00
Andrew Price c548a1c175 gfs2: Make gfs2_write_full_page static
It only gets called from aops.c and doesn't appear in any headers.

Signed-off-by: Andrew Price <anprice@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2017-02-03 08:23:47 -05:00
Al Viro 43388b21e7 fix gfs2_stuffed_write_end() on short copies
a) the page is uptodate - ->write_begin() would either fail (in which
case we don't reach ->write_end()), or unstuff the inode, or find the
page already uptodate, or do a successful call of stuffed_readpage(),
which would've made it uptodate

b) zeroing the tail in pagecache is wrong.  kill -9 at the right time
while writing unmodified file contents to the same file should _not_
leave us in a situation when read() from the file will be reporting
it full of zeroes.  Especially since that effect will be transient -
at some later point the page will be evicted and then we'll be back
to the real file contents.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-12-10 14:25:18 -05:00
Andreas Gruenbacher 1c185c02f4 gfs2: Remove dirty buffer warning from gfs2_releasepage
Unlike what its documentation suggests, the releasepage address space
operation can currently be called on dirty pages via shrink_active_list.
This may eventually be changed when the remaining code relying on the
current behavior has been fixed, but until then, it makes no sense to
warn on dirty buffers in gfs2_releasepage.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2016-08-18 08:57:04 -05:00
Fabian Frederick 47a9a52794 GFS2: use BIT() macro
Replace 1 << value shift by more explicit BIT() macro

Also fixes two bare unsigned definitions:

WARNING: Prefer 'unsigned int' to bare use of 'unsigned'
+		unsigned hsize = BIT(ip->i_depth);

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2016-08-02 12:05:27 -05:00
Benjamin Marzinski fd4c5748b8 gfs2: writeout truncated pages
When gfs2 attempts to write a page to a file that is being truncated,
and notices that the page is completely outside of the file size, it
tries to invalidate it.  However, this may require a transaction for
journaled data files to revoke any buffers from the page on the active
items list. Unfortunately, this can happen inside a log flush, where a
transaction cannot be started. Also, gfs2 may need to be able to remove
the buffer from the ail1 list before it can finish the log flush.

To deal with this, when writing a page of a file with data journalling
enabled gfs2 now skips the check to see if the write is outside the file
size, and simply writes it anyway. This situation can only occur when
the truncate code still has the file locked exclusively, and hasn't
marked this block as free in the metadata (which happens later in
truc_dealloc).  After gfs2 writes this page out, the truncation code
will shortly invalidate it and write out any revokes if necessary.

To do this, gfs2 now implements its own version of block_write_full_page
without the check, and calls the newly exported __block_write_full_page.
It also no longer calls gfs2_writepage_common from gfs2_jdata_writepage.

Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2016-06-27 10:03:12 -05:00
Linus Torvalds be1332c099 We've got nine patches this time:
- Abhi Das has two patches that fix a GFS2 splice issue (and an adjustment).
 - Ben Marzinski has a patch which allows the proper unmount of a GFS2
   file system after hitting a withdraw error.
 - I have a patch to fix a problem where GFS2 would dereference an error
   value, plus three cosmetic / refactoring patches.
 - Daniel DeFreez has a patch to fix two glock reference count problems,
   where GFS2 was not properly "uninitializing" its glock holder on error
   paths.
 - Denys Vlasenko has a patch to change a function to not be inlined,
   thus reducing the memory footprint of the GFS2 module.
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Merge tag 'gfs2-4.7.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2

Pull GFS2 updates from Bob Peterson:
 "We've got nine patches this time:

   - Abhi Das has two patches that fix a GFS2 splice issue (and an
     adjustment).

   - Ben Marzinski has a patch which allows the proper unmount of a GFS2
     file system after hitting a withdraw error.

   - I have a patch to fix a problem where GFS2 would dereference an
     error value, plus three cosmetic / refactoring patches.

   - Daniel DeFreez has a patch to fix two glock reference count
     problems, where GFS2 was not properly "uninitializing" its glock
     holder on error paths.

   - Denys Vlasenko has a patch to change a function to not be inlined,
     thus reducing the memory footprint of the GFS2 module"

* tag 'gfs2-4.7.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  GFS2: Refactor gfs2_remove_from_journal
  GFS2: Remove allocation parms from gfs2_rbm_find
  gfs2: use inode_lock/unlock instead of accessing i_mutex directly
  GFS2: Add calls to gfs2_holder_uninit in two error handlers
  GFS2: Don't dereference inode in gfs2_inode_lookup until it's valid
  GFS2: fs/gfs2/glock.c: Deinline do_error, save 1856 bytes
  gfs2: Use gfs2 wrapper to sync inode before calling generic_file_splice_read()
  GFS2: Get rid of dead code in inode_go_demote_ok
  GFS2: ignore unlock failures after withdraw
2016-05-20 15:11:26 -07:00
Bob Peterson 68cd4ce2ca GFS2: Refactor gfs2_remove_from_journal
This patch makes two simple changes to function gfs2_remove_from_journal.
First, it removes the parameter that specifies the transaction.
Since it's always passed in as current->journal_info, we might as well
set that in the function rather than passing it in. Second, it changes
the meta parameter to use an enum to make the code more clear.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
2016-05-06 11:27:27 -05:00
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
Daniel DeFreez 9c7fe83530 GFS2: Add calls to gfs2_holder_uninit in two error handlers
This patch fixes two locations that do not call gfs2_holder_uninit
if gfs2_glock_nq returns an error.

Signed-off-by: Daniel DeFreez <dcdefreez@ucdavis.edu>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2016-04-19 19:59:11 -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
Bob Peterson 2df6f47150 GFS2: Fix direct IO write rounding error
The fsx test in xfstests was failing because it was using direct IO
writes which were using a bad calculation. It was using
loff_t lstart = offset & (PAGE_CACHE_SIZE - 1); when it should be
loff_t lstart = offset & ~(PAGE_CACHE_SIZE - 1);
Thus, the write at offset 0x67e00 was calculating lstart to be
0xe00, the address of our corruption. Instead, it should have been
0x67000. This patch fixes the calculation.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
2016-03-15 10:46:28 -04:00
Bob Peterson b54e9a0b92 GFS2: Extract quota data from reservations structure (revert 5407e24)
This patch basically reverts the majority of patch 5407e24.
That patch eliminated the gfs2_qadata structure in favor of just
using the reservations structure. The problem with doing that is that
it increases the size of the reservations structure. That is not an
issue until it comes time to fold the reservations structure into the
inode in memory so we know it's always there. By separating out the
quota structure again, we aren't punishing the non-quota users by
making all the inodes bigger, requiring more slab space. This patch
creates a new slab area to allocate the quota stuff so it's managed
a little more sanely.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2015-11-24 08:38:44 -06:00
Linus Torvalds 546fac6073 GFS2: merge window
Here is a list of patches we've accumulated for GFS2 for the current upstream
 merge window. We have a good mixture this time. Here are some of the features:
 
 1. Fix a problem with RO mounts writing to the journal.
 2. Further improvements to quotas on GFS2.
 3. Added support for rename2 and RENAME_EXCHANGE on GFS2.
 4. Increase performance by making glock lru_list less of a bottleneck.
 5. Increase performance by avoiding unnecessary buffer_head releases.
 6. Increase performance by using average glock round trip time from all CPUs.
 7. Fixes for some compiler warnings and minor white space issues.
 8. Other misc. bug fixes
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Merge tag 'gfs2-merge-window' of git://git.kernel.org:/pub/scm/linux/kernel/git/gfs2/linux-gfs2

Pull GFS2 updates from Bob Peterson:
 "Here are the patches we've accumulated for GFS2 for the current
  upstream merge window.  We have a good mixture this time.  Here are
  some of the features:

   - Fix a problem with RO mounts writing to the journal.

   - Further improvements to quotas on GFS2.

   - Added support for rename2 and RENAME_EXCHANGE on GFS2.

   - Increase performance by making glock lru_list less of a bottleneck.

   - Increase performance by avoiding unnecessary buffer_head releases.

   - Increase performance by using average glock round trip time from all CPUs.

   - Fixes for some compiler warnings and minor white space issues.

   - Other misc bug fixes"

* tag 'gfs2-merge-window' of git://git.kernel.org:/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  GFS2: Don't brelse rgrp buffer_heads every allocation
  GFS2: Don't add all glocks to the lru
  gfs2: Don't support fallocate on jdata	files
  gfs2: s64 cast for negative quota value
  gfs2: limit quota log messages
  gfs2: fix quota updates on block boundaries
  gfs2: fix shadow warning in gfs2_rbm_find()
  gfs2: kerneldoc warning fixes
  gfs2: convert simple_str to kstr
  GFS2: make sure S_NOSEC flag isn't overwritten
  GFS2: add support for rename2 and RENAME_EXCHANGE
  gfs2: handle NULL rgd in set_rgrp_preferences
  GFS2: inode.c: indent with TABs, not spaces
  GFS2: mark the journal idle to fix ro mounts
  GFS2: Average in only non-zero round-trip times for congestion stats
  GFS2: Use average srttb value in congestion calculations
2015-06-27 09:47:46 -07:00
Fabian Frederick 1272574bf9 gfs2: kerneldoc warning fixes
Fixes the following kernel-doc warnings:
Warning(fs/gfs2/aops.c:180): No description found for parameter 'wbc'
Warning(fs/gfs2/aops.c:236): No description found for parameter 'end'
Warning(fs/gfs2/aops.c:236): No description found for parameter 'done_index'
Warning(fs/gfs2/aops.c:236): Excess function parameter 'writepage' description in 'gfs2_write_jdata_pagevec'
Warning(fs/gfs2/aops.c:346): Excess function parameter 'writepage' description in 'gfs2_write_cache_jdata'
Warning(fs/gfs2/aops.c:346): Excess function parameter 'data' description in 'gfs2_write_cache_jdata'
Warning(fs/gfs2/aops.c:605): No description found for parameter 'file'
Warning(fs/gfs2/aops.c:605): No description found for parameter 'mapping'
Warning(fs/gfs2/aops.c:605): No description found for parameter 'pages'
Warning(fs/gfs2/aops.c:605): No description found for parameter 'nr_pages'
Warning(fs/gfs2/aops.c:870): No description found for parameter 'copied'

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2015-05-05 13:29:54 -05:00
Linus Torvalds 4fc8adcfec Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull third hunk of vfs changes from Al Viro:
 "This contains the ->direct_IO() changes from Omar + saner
  generic_write_checks() + dealing with fcntl()/{read,write}() races
  (mirroring O_APPEND/O_DIRECT into iocb->ki_flags and instead of
  repeatedly looking at ->f_flags, which can be changed by fcntl(2),
  check ->ki_flags - which cannot) + infrastructure bits for dhowells'
  d_inode annotations + Christophs switch of /dev/loop to
  vfs_iter_write()"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (30 commits)
  block: loop: switch to VFS ITER_BVEC
  configfs: Fix inconsistent use of file_inode() vs file->f_path.dentry->d_inode
  VFS: Make pathwalk use d_is_reg() rather than S_ISREG()
  VFS: Fix up debugfs to use d_is_dir() in place of S_ISDIR()
  VFS: Combine inode checks with d_is_negative() and d_is_positive() in pathwalk
  NFS: Don't use d_inode as a variable name
  VFS: Impose ordering on accesses of d_inode and d_flags
  VFS: Add owner-filesystem positive/negative dentry checks
  nfs: generic_write_checks() shouldn't be done on swapout...
  ocfs2: use __generic_file_write_iter()
  mirror O_APPEND and O_DIRECT into iocb->ki_flags
  switch generic_write_checks() to iocb and iter
  ocfs2: move generic_write_checks() before the alignment checks
  ocfs2_file_write_iter: stop messing with ppos
  udf_file_write_iter: reorder and simplify
  fuse: ->direct_IO() doesn't need generic_write_checks()
  ext4_file_write_iter: move generic_write_checks() up
  xfs_file_aio_write_checks: switch to iocb/iov_iter
  generic_write_checks(): drop isblk argument
  blkdev_write_iter: expand generic_file_checks() call in there
  ...
2015-04-16 23:27:56 -04:00
Linus Torvalds 80dcc31fbe GFS2: merge window
Here is a list of patches we've accumulated for GFS2 for the current upstream
 merge window. Most of the patches fix GFS2 quotas, which were not properly
 enforced. There's another that adds me as a GFS2 co-maintainer, and a
 couple patches that fix a kernel panic doing splice_write on GFS2 as well
 as a few correctness patches.
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Merge tag 'gfs2-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2

Pull GFS2 updates from Bob Peterson:
 "Here is a list of patches we've accumulated for GFS2 for the current
  upstream merge window.

  Most of the patches fix GFS2 quotas, which were not properly enforced.
  There's another that adds me as a GFS2 co-maintainer, and a couple
  patches that fix a kernel panic doing splice_write on GFS2 as well as
  a few correctness patches"

* tag 'gfs2-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: fix quota refresh race in do_glock()
  gfs2: incorrect check for debugfs returns
  gfs2: allow fallocate to max out quotas/fs efficiently
  gfs2: allow quota_check and inplace_reserve to return available blocks
  gfs2: perform quota checks against allocation parameters
  GFS2: Move gfs2_file_splice_write outside of #ifdef
  GFS2: Allocate reservation during splice_write
  GFS2: gfs2_set_acl(): Cache "no acl" as well
  Add myself (Bob Peterson) as a maintainer of GFS2
2015-04-14 16:09:18 -07:00
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
Omar Sandoval 17f8c842d2 Remove rw from {,__,do_}blockdev_direct_IO()
Most filesystems call through to these at some point, so we'll start
here.

Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11 22:29:44 -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
Abhi Das b8fbf471ed gfs2: perform quota checks against allocation parameters
Use struct gfs2_alloc_parms as an argument to gfs2_quota_check()
and gfs2_quota_lock_check() to check for quota violations while
accounting for the new blocks requested by the current operation
in ap->target.

Previously, the number of new blocks requested during an operation
were not accounted for during quota_check and would allow these
operations to exceed quota. This was not very apparent since most
operations allocated only 1 block at a time and quotas would get
violated in the next operation. i.e. quota excess would only be by
1 block or so. With fallocate, (where we allocate a bunch of blocks
at once) the quota excess is non-trivial and is addressed by this
patch.

Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
2015-03-18 12:46:54 -05:00
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
Linus Torvalds 16b9057804 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
 "This the bunch that sat in -next + lock_parent() fix.  This is the
  minimal set; there's more pending stuff.

  In particular, I really hope to get acct.c fixes merged this cycle -
  we need that to deal sanely with delayed-mntput stuff.  In the next
  pile, hopefully - that series is fairly short and localized
  (kernel/acct.c, fs/super.c and fs/namespace.c).  In this pile: more
  iov_iter work.  Most of prereqs for ->splice_write with sane locking
  order are there and Kent's dio rewrite would also fit nicely on top of
  this pile"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (70 commits)
  lock_parent: don't step on stale ->d_parent of all-but-freed one
  kill generic_file_splice_write()
  ceph: switch to iter_file_splice_write()
  shmem: switch to iter_file_splice_write()
  nfs: switch to iter_splice_write_file()
  fs/splice.c: remove unneeded exports
  ocfs2: switch to iter_file_splice_write()
  ->splice_write() via ->write_iter()
  bio_vec-backed iov_iter
  optimize copy_page_{to,from}_iter()
  bury generic_file_aio_{read,write}
  lustre: get rid of messing with iovecs
  ceph: switch to ->write_iter()
  ceph_sync_direct_write: stop poking into iov_iter guts
  ceph_sync_read: stop poking into iov_iter guts
  new helper: copy_page_from_iter()
  fuse: switch to ->write_iter()
  btrfs: switch to ->write_iter()
  ocfs2: switch to ->write_iter()
  xfs: switch to ->write_iter()
  ...
2014-06-12 10:30:18 -07:00
Mel Gorman 2457aec637 mm: non-atomically mark page accessed during page cache allocation where possible
aops->write_begin may allocate a new page and make it visible only to have
mark_page_accessed called almost immediately after.  Once the page is
visible the atomic operations are necessary which is noticable overhead
when writing to an in-memory filesystem like tmpfs but should also be
noticable with fast storage.  The objective of the patch is to initialse
the accessed information with non-atomic operations before the page is
visible.

The bulk of filesystems directly or indirectly use
grab_cache_page_write_begin or find_or_create_page for the initial
allocation of a page cache page.  This patch adds an init_page_accessed()
helper which behaves like the first call to mark_page_accessed() but may
called before the page is visible and can be done non-atomically.

The primary APIs of concern in this care are the following and are used
by most filesystems.

	find_get_page
	find_lock_page
	find_or_create_page
	grab_cache_page_nowait
	grab_cache_page_write_begin

All of them are very similar in detail to the patch creates a core helper
pagecache_get_page() which takes a flags parameter that affects its
behavior such as whether the page should be marked accessed or not.  Then
old API is preserved but is basically a thin wrapper around this core
function.

Each of the filesystems are then updated to avoid calling
mark_page_accessed when it is known that the VM interfaces have already
done the job.  There is a slight snag in that the timing of the
mark_page_accessed() has now changed so in rare cases it's possible a page
gets to the end of the LRU as PageReferenced where as previously it might
have been repromoted.  This is expected to be rare but it's worth the
filesystem people thinking about it in case they see a problem with the
timing change.  It is also the case that some filesystems may be marking
pages accessed that previously did not but it makes sense that filesystems
have consistent behaviour in this regard.

The test case used to evaulate this is a simple dd of a large file done
multiple times with the file deleted on each iterations.  The size of the
file is 1/10th physical memory to avoid dirty page balancing.  In the
async case it will be possible that the workload completes without even
hitting the disk and will have variable results but highlight the impact
of mark_page_accessed for async IO.  The sync results are expected to be
more stable.  The exception is tmpfs where the normal case is for the "IO"
to not hit the disk.

The test machine was single socket and UMA to avoid any scheduling or NUMA
artifacts.  Throughput and wall times are presented for sync IO, only wall
times are shown for async as the granularity reported by dd and the
variability is unsuitable for comparison.  As async results were variable
do to writback timings, I'm only reporting the maximum figures.  The sync
results were stable enough to make the mean and stddev uninteresting.

The performance results are reported based on a run with no profiling.
Profile data is based on a separate run with oprofile running.

async dd
                                    3.15.0-rc3            3.15.0-rc3
                                       vanilla           accessed-v2
ext3    Max      elapsed     13.9900 (  0.00%)     11.5900 ( 17.16%)
tmpfs	Max      elapsed      0.5100 (  0.00%)      0.4900 (  3.92%)
btrfs   Max      elapsed     12.8100 (  0.00%)     12.7800 (  0.23%)
ext4	Max      elapsed     18.6000 (  0.00%)     13.3400 ( 28.28%)
xfs	Max      elapsed     12.5600 (  0.00%)      2.0900 ( 83.36%)

The XFS figure is a bit strange as it managed to avoid a worst case by
sheer luck but the average figures looked reasonable.

        samples percentage
ext3       86107    0.9783  vmlinux-3.15.0-rc4-vanilla        mark_page_accessed
ext3       23833    0.2710  vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed
ext3        5036    0.0573  vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed
ext4       64566    0.8961  vmlinux-3.15.0-rc4-vanilla        mark_page_accessed
ext4        5322    0.0713  vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed
ext4        2869    0.0384  vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed
xfs        62126    1.7675  vmlinux-3.15.0-rc4-vanilla        mark_page_accessed
xfs         1904    0.0554  vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed
xfs          103    0.0030  vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed
btrfs      10655    0.1338  vmlinux-3.15.0-rc4-vanilla        mark_page_accessed
btrfs       2020    0.0273  vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed
btrfs        587    0.0079  vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed
tmpfs      59562    3.2628  vmlinux-3.15.0-rc4-vanilla        mark_page_accessed
tmpfs       1210    0.0696  vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed
tmpfs         94    0.0054  vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed

[akpm@linux-foundation.org: don't run init_page_accessed() against an uninitialised pointer]
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Jan Kara <jack@suse.cz>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Tested-by: Prabhakar Lad <prabhakar.csengg@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 16:54:10 -07:00
Benjamin Marzinski 24972557b1 GFS2: remove transaction glock
GFS2 has a transaction glock, which must be grabbed for every
transaction, whose purpose is to deal with freezing the filesystem.
Aside from this involving a large amount of locking, it is very easy to
make the current fsfreeze code hang on unfreezing.

This patch rewrites how gfs2 handles freezing the filesystem. The
transaction glock is removed. In it's place is a freeze glock, which is
cached (but not held) in a shared state by every node in the cluster
when the filesystem is mounted. This lock only needs to be grabbed on
freezing, and actions which need to be safe from freezing, like
recovery.

When a node wants to freeze the filesystem, it grabs this glock
exclusively.  When the freeze glock state changes on the nodes (either
from shared to unlocked, or shared to exclusive), the filesystem does a
special log flush.  gfs2_log_flush() does all the work for flushing out
the and shutting down the incore log, and then it tries to grab the
freeze glock in a shared state again.  Since the filesystem is stuck in
gfs2_log_flush, no new transaction can start, and nothing can be written
to disk. Unfreezing the filesytem simply involes dropping the freeze
glock, allowing gfs2_log_flush() to grab and then release the shared
lock, so it is cached for next time.

However, in order for the unfreezing ioctl to occur, gfs2 needs to get a
shared lock on the filesystem root directory inode to check permissions.
If that glock has already been grabbed exclusively, fsfreeze will be
unable to get the shared lock and unfreeze the filesystem.

In order to allow the unfreeze, this patch makes gfs2 grab a shared lock
on the filesystem root directory during the freeze, and hold it until it
unfreezes the filesystem.  The functions which need to grab a shared
lock in order to allow the unfreeze ioctl to be issued now use the lock
grabbed by the freeze code instead.

The freeze and unfreeze code take care to make sure that this shared
lock will not be dropped while another process is using it.

Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-05-14 10:04:34 +01:00
Al Viro 31b140398c switch {__,}blockdev_direct_IO() to iov_iter
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-05-06 17:32:46 -04:00
Al Viro a6cbcd4a4a get rid of pointless iov_length() in ->direct_IO()
all callers have iov_length(iter->iov, iter->nr_segs) == iov_iter_count(iter)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-05-06 17:32:45 -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