Commit Graph

203 Commits

Author SHA1 Message Date
Andreas Gruenbacher d0a22a4b03 gfs2: Fix iomap write page reclaim deadlock
Since commit 64bc06bb32 ("gfs2: iomap buffered write support"), gfs2 is doing
buffered writes by starting a transaction in iomap_begin, writing a range of
pages, and ending that transaction in iomap_end.  This approach suffers from
two problems:

  (1) Any allocations necessary for the write are done in iomap_begin, so when
  the data aren't journaled, there is no need for keeping the transaction open
  until iomap_end.

  (2) Transactions keep the gfs2 log flush lock held.  When
  iomap_file_buffered_write calls balance_dirty_pages, this can end up calling
  gfs2_write_inode, which will try to flush the log.  This requires taking the
  log flush lock which is already held, resulting in a deadlock.

Fix both of these issues by not keeping transactions open from iomap_begin to
iomap_end.  Instead, start a small transaction in page_prepare and end it in
page_done when necessary.

Reported-by: Edwin Török <edvin.torok@citrix.com>
Fixes: 64bc06bb32 ("gfs2: iomap buffered write support")
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2019-05-07 23:39:15 +02:00
Andreas Gruenbacher fbb27873f2 gfs2: Rename gfs2_trans_{add_unrevoke => remove_revoke}
Rename gfs2_trans_add_unrevoke to gfs2_trans_remove_revoke: there is no
such thing as an "unrevoke" object; all this function does is remove
existing revoke objects plus some bookkeeping.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-05-07 23:39:14 +02:00
Bob Peterson 7c70b89695 gfs2: clean_journal improperly set sd_log_flush_head
This patch fixes regressions in 588bff95c9.
Due to that patch, function clean_journal was setting the value of
sd_log_flush_head, but that's only valid if it is replaying the node's
own journal. If it's replaying another node's journal, that's completely
wrong and will lead to multiple problems. This patch tries to clean up
the mess by passing the value of the logical journal block number into
gfs2_write_log_header so the function can treat non-owned journals
generically. For the local journal, the journal extent map is used for
best performance. For other nodes from other journals, new function
gfs2_lblk_to_dblk is called to figure it out using gfs2_iomap_get.

This patch also tries to establish more consistency when passing journal
block parameters by changing several unsigned int types to a consistent
u32.

Fixes: 588bff95c9 ("GFS2: Reduce code redundancy writing log headers")
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-05-07 23:39:04 +02:00
Linus Torvalds b4b52b881c Wimplicit-fallthrough patches for 5.2-rc1
Hi Linus,
 
 This is my very first pull-request.  I've been working full-time as
 a kernel developer for more than two years now. During this time I've
 been fixing bugs reported by Coverity all over the tree and, as part
 of my work, I'm also contributing to the KSPP. My work in the kernel
 community has been supervised by Greg KH and Kees Cook.
 
 OK. So, after the quick introduction above, please, pull the following
 patches that mark switch cases where we are expecting to fall through.
 These patches are part of the ongoing efforts to enable -Wimplicit-fallthrough.
 They have been ignored for a long time (most of them more than 3 months,
 even after pinging multiple times), which is the reason why I've created
 this tree. Most of them have been baking in linux-next for a whole development
 cycle. And with Stephen Rothwell's help, we've had linux-next nag-emails
 going out for newly introduced code that triggers -Wimplicit-fallthrough
 to avoid gaining more of these cases while we work to remove the ones
 that are already present.
 
 I'm happy to let you know that we are getting close to completing this
 work.  Currently, there are only 32 of 2311 of these cases left to be
 addressed in linux-next.  I'm auditing every case; I take a look into
 the code and analyze it in order to determine if I'm dealing with an
 actual bug or a false positive, as explained here:
 
 https://lore.kernel.org/lkml/c2fad584-1705-a5f2-d63c-824e9b96cf50@embeddedor.com/
 
 While working on this, I've found and fixed the following missing
 break/return bugs, some of them introduced more than 5 years ago:
 
 84242b82d8
 7850b51b6c
 5e420fe635
 09186e5034
 b5be853181
 7264235ee7
 cc5034a5d2
 479826cc86
 5340f23df8
 df997abeeb
 2f10d82373
 307b00c5e6
 5d25ff7a54
 a7ed5b3e7d
 c24bfa8f21
 ad0eaee619
 9ba8376ce1
 dc586a60a1
 a8e9b186f1
 4e57562b48
 60747828ea
 c5b974bee9
 cc44ba9116
 2c930e3d0a
 
 Once this work is finish, we'll be able to universally enable
 "-Wimplicit-fallthrough" to avoid any of these kinds of bugs from
 entering the kernel again.
 
 Thanks
 
 Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
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Merge tag 'Wimplicit-fallthrough-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux

Pull Wimplicit-fallthrough updates from Gustavo A. R. Silva:
 "Mark switch cases where we are expecting to fall through.

  This is part of the ongoing efforts to enable -Wimplicit-fallthrough.

  Most of them have been baking in linux-next for a whole development
  cycle. And with Stephen Rothwell's help, we've had linux-next
  nag-emails going out for newly introduced code that triggers
  -Wimplicit-fallthrough to avoid gaining more of these cases while we
  work to remove the ones that are already present.

  We are getting close to completing this work. Currently, there are
  only 32 of 2311 of these cases left to be addressed in linux-next. I'm
  auditing every case; I take a look into the code and analyze it in
  order to determine if I'm dealing with an actual bug or a false
  positive, as explained here:

      https://lore.kernel.org/lkml/c2fad584-1705-a5f2-d63c-824e9b96cf50@embeddedor.com/

  While working on this, I've found and fixed the several missing
  break/return bugs, some of them introduced more than 5 years ago.

  Once this work is finished, we'll be able to universally enable
  "-Wimplicit-fallthrough" to avoid any of these kinds of bugs from
  entering the kernel again"

* tag 'Wimplicit-fallthrough-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux: (27 commits)
  memstick: mark expected switch fall-throughs
  drm/nouveau/nvkm: mark expected switch fall-throughs
  NFC: st21nfca: Fix fall-through warnings
  NFC: pn533: mark expected switch fall-throughs
  block: Mark expected switch fall-throughs
  ASN.1: mark expected switch fall-through
  lib/cmdline.c: mark expected switch fall-throughs
  lib: zstd: Mark expected switch fall-throughs
  scsi: sym53c8xx_2: sym_nvram: Mark expected switch fall-through
  scsi: sym53c8xx_2: sym_hipd: mark expected switch fall-throughs
  scsi: ppa: mark expected switch fall-through
  scsi: osst: mark expected switch fall-throughs
  scsi: lpfc: lpfc_scsi: Mark expected switch fall-throughs
  scsi: lpfc: lpfc_nvme: Mark expected switch fall-through
  scsi: lpfc: lpfc_nportdisc: Mark expected switch fall-through
  scsi: lpfc: lpfc_hbadisc: Mark expected switch fall-throughs
  scsi: lpfc: lpfc_els: Mark expected switch fall-throughs
  scsi: lpfc: lpfc_ct: Mark expected switch fall-throughs
  scsi: imm: mark expected switch fall-throughs
  scsi: csiostor: csio_wr: mark expected switch fall-through
  ...
2019-05-07 12:48:10 -07:00
Andreas Gruenbacher df0db3ecdb iomap: Add a page_prepare callback
Move the page_done callback into a separate iomap_page_ops structure and
add a page_prepare calback to be called before the next page is written
to.  In gfs2, we'll want to start a transaction in page_prepare and end
it in page_done.  Other filesystems that implement data journaling will
require the same kind of mechanism.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-05-01 07:47:37 -07:00
Gustavo A. R. Silva 0a4c92657f fs: mark expected switch fall-throughs
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

This patch fixes the following warnings:

fs/affs/affs.h:124:38: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/configfs/dir.c:1692:11: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/configfs/dir.c:1694:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ceph/file.c:249:3: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/hash.c:233:15: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/hash.c:246:15: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext2/inode.c:1237:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext2/inode.c:1244:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/indirect.c:1182:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/indirect.c:1188:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/indirect.c:1432:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/indirect.c:1440:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/f2fs/node.c:618:8: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/f2fs/node.c:620:8: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/btrfs/ref-verify.c:522:15: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/gfs2/bmap.c:711:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/gfs2/bmap.c:722:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/jffs2/fs.c:339:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/nfsd/nfs4proc.c:429:12: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ufs/util.h:62:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ufs/util.h:43:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/fcntl.c:770:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/seq_file.c:319:10: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/libfs.c:148:11: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/libfs.c:150:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/signalfd.c:178:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/locks.c:1473:16: warning: this statement may fall through [-Wimplicit-fallthrough=]

Warning level 3 was used: -Wimplicit-fallthrough=3

This patch is part of the ongoing efforts to enabling
-Wimplicit-fallthrough.

Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2019-04-08 18:21:02 -05:00
Bob Peterson bc0205612b gfs2: take jdata unstuff into account in do_grow
Before this patch, function do_grow would not reserve enough journal
blocks in the transaction to unstuff jdata files while growing them.
This patch adds the logic to add one more block if the file to grow
is jdata.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
2018-12-18 10:49:02 -06:00
Abhi Das 98583b3e87 gfs2: add more timing info to journal recovery process
Tells you how many milliseconds map_journal_extents and find_jhead
take.

Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2018-12-11 17:50:36 +01:00
Linus Torvalds e6a2562fe2 Merge tag 'gfs2-4.20.fixes3' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2
Pull bfs2 fixes from Andreas Gruenbacher:
 "Fix two bugs leading to leaked buffer head references:

   - gfs2: Put bitmap buffers in put_super
   - gfs2: Fix iomap buffer head reference counting bug

  And one bug leading to significant slow-downs when deleting large
  files:

   - gfs2: Fix metadata read-ahead during truncate (2)"

* tag 'gfs2-4.20.fixes3' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: Fix iomap buffer head reference counting bug
  gfs2: Fix metadata read-ahead during truncate (2)
  gfs2: Put bitmap buffers in put_super
2018-11-16 11:38:14 -06:00
Andreas Gruenbacher c26b5aa8ef gfs2: Fix iomap buffer head reference counting bug
GFS2 passes the inode buffer head (dibh) from gfs2_iomap_begin to
gfs2_iomap_end in iomap->private.  It sets that private pointer in
gfs2_iomap_get.  Users of gfs2_iomap_get other than gfs2_iomap_begin
would have to release iomap->private, but this isn't done correctly,
leading to a leak of buffer head references.

To fix this, move the code for setting iomap->private from
gfs2_iomap_get to gfs2_iomap_begin.

Fixes: 64bc06bb32 ("gfs2: iomap buffered write support")
Cc: stable@vger.kernel.org # v4.19+
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-11-16 11:35:09 -06:00
Andreas Gruenbacher e7445ceddf gfs2: Fix metadata read-ahead during truncate (2)
The previous attempt to fix for metadata read-ahead during truncate was
incorrect: for files with a height > 2 (1006989312 bytes with a block
size of 4096 bytes), read-ahead requests were not being issued for some
of the indirect blocks discovered while walking the metadata tree,
leading to significant slow-downs when deleting large files.  Fix that.

In addition, only issue read-ahead requests in the first pass through
the meta-data tree, while deallocating data blocks.

Fixes: c3ce5aa9b0 ("gfs2: Fix metadata read-ahead during truncate")
Cc: stable@vger.kernel.org # v4.16+
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2018-11-09 10:55:33 +00:00
Linus Torvalds bfd93a87ea We've got 18 patches for this merge window, none of which are very major.
1. Andreas Gruenbacher contributed several patches to clean up the gfs2
    block allocator to prepare for future performance enhancements.
 2. Andy Price contributed a patch to fix a use-after-free problem.
 3. I contributed some patches that fix gfs2's broken rgrplvb mount option.
 4. I contributed some cleanup patches and error message improvements.
 5. Steve Whitehouse and Abhi Das sent a patch to enable getlabel support.
 6. Tim Smith contributed a patch to flush the glock delete workqueue at exit.
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Merge tag 'gfs2-4.20.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2

Pull gfs2 updates from Bob Peterson:
 "We've got 18 patches for this merge window, none of which are very
  major:

   - clean up the gfs2 block allocator to prepare for future performance
     enhancements (Andreas Gruenbacher)

   - fix a use-after-free problem (Andy Price)

   - patches that fix gfs2's broken rgrplvb mount option (me)

   - cleanup patches and error message improvements (me)

   - enable getlabel support (Steve Whitehouse and Abhi Das)

   - flush the glock delete workqueue at exit (Tim Smith)"

* tag 'gfs2-4.20.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: Fix minor typo: couln't versus couldn't.
  gfs2: write revokes should traverse sd_ail1_list in reverse
  gfs2: Pass resource group to rgblk_free
  gfs2: Remove unnecessary gfs2_rlist_alloc parameter
  gfs2: Fix marking bitmaps non-full
  gfs2: Fix some minor typos
  gfs2: Rename bitmap.bi_{len => bytes}
  gfs2: Remove unused RGRP_RSRV_MINBYTES definition
  gfs2: Move rs_{sizehint, rgd_gh} fields into the inode
  gfs2: Clean up out-of-bounds check in gfs2_rbm_from_block
  gfs2: Always check the result of gfs2_rbm_from_block
  gfs2: getlabel support
  GFS2: Flush the GFS2 delete workqueue before stopping the kernel threads
  gfs2: Don't leave s_fs_info pointing to freed memory in init_sbd
  gfs2: Use fs_* functions instead of pr_* function where we can
  gfs2: slow the deluge of io error messages
  gfs2: Don't set GFS2_RDF_UPTODATE when the lvb is updated
  gfs2: improve debug information when lvb mismatches are found
2018-10-24 17:30:39 +01:00
Andreas Gruenbacher fee5150c48 gfs2: Fix iomap buffered write support for journaled files (2)
It turns out that the fix in commit 6636c3cc56 is bad; the assertion
that the iomap code no longer creates buffer heads is incorrect for
filesystems that set the IOMAP_F_BUFFER_HEAD flag.

Instead, what's happening is that gfs2_iomap_begin_write treats all
files that have the jdata flag set as journaled files, which is
incorrect as long as those files are inline ("stuffed").  We're handling
stuffed files directly via the page cache, which is why we ended up with
pages without buffer heads in gfs2_page_add_databufs.

Fix this by handling stuffed journaled files correctly in
gfs2_iomap_begin_write.

This reverts commit 6636c3cc5690c11631e6366cf9a28fb99c8b25bb.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2018-10-12 17:14:42 +02:00
Andreas Gruenbacher 0ddeded4ae gfs2: Pass resource group to rgblk_free
Function rgblk_free can only deal with one resource group at a time, so
pass that resource group is as a parameter.  Several of the callers
already have the resource group at hand, so we only need additional
lookup code in a few places.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Steven Whitehouse <swhiteho@redhat.com>
2018-10-12 07:33:07 -05:00
Andreas Gruenbacher dc480feb45 gfs2: Fix iomap buffered write support for journaled files
Commit 64bc06bb32 broke buffered writes to journaled files (chattr
+j): we'll try to journal the buffer heads of the page being written to
in gfs2_iomap_journaled_page_done.  However, the iomap code no longer
creates buffer heads, so we'll BUG() in gfs2_page_add_databufs.  Fix
that by creating buffer heads ourself when needed.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2018-10-09 18:20:13 +02:00
Andreas Gruenbacher 776125785a gfs2: Special-case rindex for gfs2_grow
To speed up the common case of appending to a file,
gfs2_write_alloc_required presumes that writing beyond the end of a file
will always require additional blocks to be allocated.  This assumption
is incorrect for preallocates files, but there are no negative
consequences as long as *some* space is still left on the filesystem.

One special file that always has some space preallocated beyond the end
of the file is the rindex: when growing a filesystem, gfs2_grow adds one
or more new resource groups and appends records describing those
resource groups to the rindex; the preallocated space ensures that this
is always possible.

However, when a filesystem is completely full, gfs2_write_alloc_required
will indicate that an additional allocation is required, and appending
the next record to the rindex will fail even though space for that
record has already been preallocated.  To fix that, skip the incorrect
optimization in gfs2_write_alloc_required, but for the rindex only.
Other writes to preallocated space beyond the end of the file are still
allowed to fail on completely full filesystems.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Bob Peterson <rpeterso@redhat.com>
2018-07-25 22:56:14 +02:00
Andreas Gruenbacher 0ed91eca11 Merge branch 'iomap-4.19-merge' into linux-gfs2/for-next
Merge xfs branch 'iomap-4.19-merge' into linux-gfs2/for-next.  This
brings in readpage and direct I/O support for inline data.

The IOMAP_F_BUFFER_HEAD flag introduced in commit "iomap: add initial
support for writes without buffer heads" needs to be set for gfs2 as
well, so do that in the merge.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2018-07-25 00:08:20 +02:00
Andreas Gruenbacher a3479c7fc0 Merge branch 'iomap-write' into linux-gfs2/for-next
Pull in the gfs2 iomap-write changes: Tweak the existing code to
properly support iomap write and eliminate an unnecessary special case
in gfs2_block_map.  Implement iomap write support for buffered and
direct I/O.  Simplify some of the existing code and eliminate code that
is no longer used:

  gfs2: Remove gfs2_write_{begin,end}
  gfs2: iomap direct I/O support
  gfs2: gfs2_extent_length cleanup
  gfs2: iomap buffered write support
  gfs2: Further iomap cleanups

This is based on the following changes on the xfs 'iomap-4.19-merge'
branch:

  iomap: add private pointer to struct iomap
  iomap: add a page_done callback
  iomap: generic inline data handling
  iomap: complete partial direct I/O writes synchronously
  iomap: mark newly allocated buffer heads as new
  fs: factor out a __generic_write_end helper

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2018-07-24 20:02:40 +02:00
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 bcfe94139a gfs2: gfs2_extent_length cleanup
Now that gfs2_extent_length is no longer used for determining the size
of a hole and always with an upper size limit, the function can be
simplified.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Bob Peterson <rpeterso@redhat.com>
2018-07-02 16:27:24 +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 d505a96a3b gfs2: Further iomap cleanups
In gfs2_iomap_alloc, set the type of newly allocated extents to
IOMAP_MAPPED so that iomap_to_bh will set the bh states correctly:
otherwise, the bhs would not be marked as mapped, confusing
__mpage_writepage.  This means that we need to check for the IOMAP_F_NEW
flag in fallocate_chunk now.

Further clean up gfs2_iomap_get and implement gfs2_stuffed_iomap here
directly.  For reads beyond the end of the file, return holes instead of
failing with -ENOENT so that we can get rid of that special case in
gfs2_block_map.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Bob Peterson <rpeterso@redhat.com>
2018-07-02 16:26:01 +01:00
Andreas Gruenbacher 00251a16d7 gfs2: Minor clarification to __gfs2_punch_hole
Rename end_off to end_len to make the code less confusing.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-06-21 07:40:00 -05:00
Linus Torvalds 6567af78ac Changes for 4.18:
- Strengthen inode number and structure validation when allocating inodes.
 - Reduce pointless buffer allocations during cache miss
 - Use FUA for pure data O_DSYNC directio writes
 - Various iomap refactorings
 - Strengthen quota metadata verification to avoid unfixable broken quota
 - Make AGFL block freeing a deferred operation to avoid blowing out
   transaction reservations when running complex operations
 - Get rid of the log item descriptors to reduce log overhead
 - Fix various reflink bugs where inodes were double-joined to
   transactions
 - Don't issue discards when trimming unwritten extents
 - Refactor incore dquot initialization and retrieval interfaces
 - Fix some locking problmes in the quota scrub code
 - Strengthen btree structure checks in scrub code
 - Rewrite swapfile activation to use iomap and support unwritten extents
 - Make scrub exit to userspace sooner when corruptions or
   cross-referencing problems are found
 - Make scrub invoke the data fork scrubber directly on metadata inodes
 - Don't do background reclamation of post-eof and cow blocks when the fs
   is suspended
 - Fix secondary superblock buffer lifespan hinting
 - Refactor growfs to use table-dispatched functions instead of long
   stringy functions
 - Move growfs code to libxfs
 - Implement online fs label getting and setting
 - Introduce online filesystem repair (in a very limited capacity)
 - Fix unit conversion problems in the realtime freemap iteration
   functions
 - Various refactorings and cleanups in preparation to remove buffer
   heads in a future release
 - Reimplement the old bmap call with iomap
 - Remove direct buffer head accesses from seek hole/data
 - Various bug fixes
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Merge tag 'xfs-4.18-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull xfs updates from Darrick Wong:
 "New features this cycle include the ability to relabel mounted
  filesystems, support for fallocated swapfiles, and using FUA for pure
  data O_DSYNC directio writes. With this cycle we begin to integrate
  online filesystem repair and refactor the growfs code in preparation
  for eventual subvolume support, though the road ahead for both
  features is quite long.

  There are also numerous refactorings of the iomap code to remove
  unnecessary log overhead, to disentangle some of the quota code, and
  to prepare for buffer head removal in a future upstream kernel.

  Metadata validation continues to improve, both in the hot path
  veifiers and the online filesystem check code. I anticipate sending a
  second pull request in a few days with more metadata validation
  improvements.

  This series has been run through a full xfstests run over the weekend
  and through a quick xfstests run against this morning's master, with
  no major failures reported.

  Summary:

   - Strengthen inode number and structure validation when allocating
     inodes.

   - Reduce pointless buffer allocations during cache miss

   - Use FUA for pure data O_DSYNC directio writes

   - Various iomap refactorings

   - Strengthen quota metadata verification to avoid unfixable broken
     quota

   - Make AGFL block freeing a deferred operation to avoid blowing out
     transaction reservations when running complex operations

   - Get rid of the log item descriptors to reduce log overhead

   - Fix various reflink bugs where inodes were double-joined to
     transactions

   - Don't issue discards when trimming unwritten extents

   - Refactor incore dquot initialization and retrieval interfaces

   - Fix some locking problmes in the quota scrub code

   - Strengthen btree structure checks in scrub code

   - Rewrite swapfile activation to use iomap and support unwritten
     extents

   - Make scrub exit to userspace sooner when corruptions or
     cross-referencing problems are found

   - Make scrub invoke the data fork scrubber directly on metadata
     inodes

   - Don't do background reclamation of post-eof and cow blocks when the
     fs is suspended

   - Fix secondary superblock buffer lifespan hinting

   - Refactor growfs to use table-dispatched functions instead of long
     stringy functions

   - Move growfs code to libxfs

   - Implement online fs label getting and setting

   - Introduce online filesystem repair (in a very limited capacity)

   - Fix unit conversion problems in the realtime freemap iteration
     functions

   - Various refactorings and cleanups in preparation to remove buffer
     heads in a future release

   - Reimplement the old bmap call with iomap

   - Remove direct buffer head accesses from seek hole/data

   - Various bug fixes"

* tag 'xfs-4.18-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (121 commits)
  fs: use ->is_partially_uptodate in page_cache_seek_hole_data
  fs: remove the buffer_unwritten check in page_seek_hole_data
  fs: move page_cache_seek_hole_data to iomap.c
  xfs: use iomap_bmap
  iomap: add an iomap-based bmap implementation
  iomap: add a iomap_sector helper
  iomap: use __bio_add_page in iomap_dio_zero
  iomap: move IOMAP_F_BOUNDARY to gfs2
  iomap: fix the comment describing IOMAP_NOWAIT
  iomap: inline data should be an iomap type, not a flag
  mm: split ->readpages calls to avoid non-contiguous pages lists
  mm: return an unsigned int from __do_page_cache_readahead
  mm: give the 'ret' variable a better name __do_page_cache_readahead
  block: add a lower-level bio_add_page interface
  xfs: fix error handling in xfs_refcount_insert()
  xfs: fix xfs_rtalloc_rec units
  xfs: strengthen rtalloc query range checks
  xfs: xfs_rtbuf_get should check the bmapi_read results
  xfs: xfs_rtword_t should be unsigned, not signed
  dax: change bdev_dax_supported() to support boolean returns
  ...
2018-06-05 13:24:20 -07:00
Andreas Gruenbacher 628e366df1 gfs2: Iomap cleanups and improvements
Clean up gfs2_iomap_alloc and gfs2_iomap_get.  Document how
gfs2_iomap_alloc works: it now needs to be called separately after
gfs2_iomap_get where necessary; this will be used later by iomap write.
Move gfs2_iomap_ops into bmap.c.

Introduce a new gfs2_iomap_get_alloc helper and use it in
fallocate_chunk: gfs2_iomap_begin will become unsuitable for fallocate
with proper iomap write support.

In gfs2_block_map and fallocate_chunk, zero-initialize struct iomap.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-06-04 07:56:51 -05:00
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 7841b9f084 gfs2: hole_size improvement
Reimplement function hole_size based on a generic function for walking
the metadata tree and rename hole_size to gfs2_hole_size.  While
previously, multiple invocations of hole_size were sometimes needed to
walk across the entire hole, the new implementation always returns the
entire hole at once (provided that the caller is interested in the total
size).

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-06-04 07:39:23 -05:00
Andreas Gruenbacher 07e23d68f6 gfs2: Update find_metapath comment
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-06-04 07:32:44 -05:00
Christoph Hellwig 7ee66c03e4 iomap: move IOMAP_F_BOUNDARY to gfs2
Just define a range of fs specific flags and use that in gfs2 instead of
exposing this internal flag globally.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-06-01 18:37:32 -07:00
Christoph Hellwig 19319b5321 iomap: inline data should be an iomap type, not a flag
Inline data is fundamentally different from our normal mapped case in that
it doesn't even have a block address.  So instead of having a flag for it
it should be an entirely separate iomap range type.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-06-01 18:37:32 -07:00
Andreas Gruenbacher 9a38662ba4 gfs2: Remove sdp->sd_jheightsize
GFS2 keeps two arrarys in the superblock that define the maximum size of
an inode depending on the inode's height: sdp->sd_heightsize defines the
heights in units of sb->s_blocksize; sdp->sd_jheightsize defines them in
units of sb->s_blocksize - sizeof(struct gfs2_meta_header).  These
arrays are used to determine when additional layers of indirect blocks
are needed.  The second array is used for directories which have an
additional gfs2_meta_header at the beginning of each block.

Distinguishing between these two cases makes no sense: the height
required for representing N blocks will come out the same no matter if
the calculation is done in gross (sb->s_blocksize) or net
(sb->s_blocksize - sizeof(struct gfs2_meta_header)) units.

Stuffed directories don't have an additional gfs2_meta_header, but the
stuffed case is handled separately for both files and directories,
anyway.

Remove the unncessary sdp->sd_jheightsize array.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-04-16 09:25:21 -07:00
Bob Peterson 3e7aafc39c GFS2: Minor improvements to comments and documentation
This patch simply fixes some comments and the gfs2-glocks.txt file:
Places where i_rwsem was called i_mutex, and adding i_rw_mutex.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-04-12 10:07:51 -07:00
Andreas Gruenbacher fffb64127a gfs2: Zero out fallocated blocks in fallocate_chunk
Instead of zeroing out fallocated blocks in gfs2_iomap_alloc, zero them
out in fallocate_chunk, much higher up the call stack.  This gets rid of
gfs2's abuse of the IOMAP_ZERO flag as well as the gfs2 specific zeronew
buffer flag.  I can't think of a reason why zeroing out the blocks in
gfs2_iomap_alloc would have any benefits: there is no additional locking
at that level that would add protection to the newly allocated blocks.

While at it, change fallocate over from gs2_block_map to gfs2_iomap_begin.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
2018-03-29 06:50:32 -07:00
Andreas Gruenbacher bb491ce67a gfs2: Check for the end of metadata in punch_hole
When punching a hole or truncating an inode down to a given size, also
check if the truncate point / start of the hole is within the range we
have metadata for.  Otherwise, we can end up freeing blocks that
shouldn't be freed, corrupting the inode, or crashing the machine when
trying to punch a hole into the void.

When growing an inode via truncate, we set the new size but we don't
allocate additional levels of indirect blocks and grow the inode height.
When shrinking that inode again, the new size may still point beyond the
end of the inode's metadata.

Fixes xfstest generic/476.

Debugged-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-03-23 11:43:02 -07:00
Andreas Gruenbacher d39d18e0ef gfs2: Improve gfs2_block_map comment
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-03-08 09:26:20 -07:00
Andreas Gruenbacher 3b5da96e45 gfs2: Fixes to "Implement iomap for block_map" (2)
It turns out that commit 3229c18c0d6b2 'Fixes to "Implement iomap for
block_map"' introduced another bug in gfs2_iomap_begin that can cause
gfs2_block_map to set bh->b_size of an actual buffer to 0.  This can
lead to arbitrary incorrect behavior including crashes or disk
corruption.  Revert the incorrect part of that commit.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-03-07 11:40:38 -07:00
Andreas Gruenbacher 49edd5bf42 gfs2: Fixes to "Implement iomap for block_map"
It turns out that commit 3974320ca6 "Implement iomap for block_map"
introduced a few bugs that trigger occasional failures with xfstest
generic/476:

In gfs2_iomap_begin, we jump to do_alloc when we determine that we are
beyond the end of the allocated metadata (height > ip->i_height).
There, we can end up calling hole_size with a metapath that doesn't
match the current metadata tree, which doesn't make sense.  After
untangling the code at do_alloc, fix this by checking if the block we
are looking for is within the range of allocated metadata.

In addition, add a BUG() in case gfs2_iomap_begin is accidentally called
for reading stuffed files: this is handled separately.  Make sure we
don't truncate iomap->length for reads beyond the end of the file; in
that case, the entire range counts as a hole.

Finally, revert to taking a bitmap write lock when doing allocations.
It's unclear why that change didn't lead to any failures during testing.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-02-13 13:38:10 -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 4e56a6411f gfs2: Implement fallocate(FALLOC_FL_PUNCH_HOLE)
Implement the top-level bits of punching a hole into a file.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-01-18 21:15:58 +01:00
Andreas Gruenbacher 10d2cf94c2 gfs2: Turn trunc_dealloc into punch_hole
Add an upper bound to the range of blocks to deallocate blocks to
function trunc_dealloc so that this function can be used for truncating
a file as well as for punching a hole into a file.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-01-18 21:15:57 +01:00
Andreas Gruenbacher 5cf26b1e88 gfs2: Generalize truncate code
Pull the code for computing the range of metapointers to iterate out of
gfs2_metapath_ra (for readahead), sweep_bh_for_rgrps (for deallocating
metapointers within a block), and trunc_dealloc (for walking the
metadata tree).

In sweep_bh_for_rgrps, move the code for looking up the resource group
descriptor of the current resource group out of the inner loop.  The
metatype check moves to trunc_dealloc.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-01-18 21:15:37 +01:00
Andreas Gruenbacher bdba0d5ec1 Turn gfs2_block_truncate_page into gfs2_block_zero_range
Turn gfs2_block_truncate_page into a function that zeroes a range within
a block rather than only the end of a block.  This will be used for
cleaning the end of the first partial block and the start of the last
partial block when punching a hole in a file.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-01-17 06:35:53 -07:00
Andreas Gruenbacher cb7f0903ef gfs2: Improve non-recursive delete algorithm
In rare cases, the current non-recursive delete algorithm doesn't
deallocate empty intermediary indirect blocks.  This should have very
little practical effect, but deallocating all blocks correctly should
still be preferable as it is cleaner and easier to validate.

The fix consists of using the first block to deallocate to compute the
start marker of the truncate point instead of the last block that needs
to be kept.  With that change, computing which indirect blocks are still
needed becomes relatively easy.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-01-17 06:35:52 -07:00
Andreas Gruenbacher c3ce5aa9b0 gfs2: Fix metadata read-ahead during truncate
The metadata read-ahead algorithm broke when switching from recursive to
non-recursive delete: the current algorithm reads ahead blocks at height
N - 1 while deallocating the blocks at hight N.  However, deallocating
the blocks at height N requires a complete walk of the metadata tree,
not only down to height N - 1.  Consequently, all blocks below height
N - 1 will be accessed without read-ahead.

Fix this by issuing read-aheads as early as possible, after each
metapath lookup.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-01-17 06:35:50 -07:00
Andreas Gruenbacher e8b43fe0c1 gfs2: Clean up {lookup,fillup}_metapath
Split out the entire lookup loop from lookup_metapath and
fillup_metapath.  Make both functions return the actual height in
mp->mp_aheight, and return 0 on success.  Handle lookup errors properly
in trunc_dealloc.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-01-17 06:35:48 -07:00
Andreas Gruenbacher e7fdf00406 gfs2: Remove minor gfs2_journaled_truncate inefficiencies
First, this function truncates the file in chunks.  When the original
file size isn't block aligned, each chunk that is truncated will remain
be misaligned.  This is inefficient.

Second, this function doesn't recognize where holes are, so it loops
through them.  For each chunk of a hole, it creates a new transaction.
At least avoid creating another transactions whe the current one is
still empty.  (An better fix would be to skip large holes, of course.)

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-01-17 06:35:47 -07:00
Andreas Gruenbacher 8b5860a35c gfs2: truncate: Remove unnecessary oldsize parameters
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-01-17 06:35:45 -07:00
Andreas Gruenbacher 80990f404d gfs2: Clean up trunc_start error path
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-01-17 06:35:42 -07:00
Steven Whitehouse 90bcab998d gfs2: Add gfs2_blk2rgrpd comment and fix incorrect use
Document when to use gfs2_blk2rgrpd for "inexact" resource group
matching.  Based on that, fix an incorrect use of gfs2_blk2rgrpd in
sweep_bh_for_rgrps.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2018-01-17 06:34:24 -07:00
Bob Peterson 3974320ca6 GFS2: Implement iomap for block_map
This patch implements iomap for block mapping, and switches the
block_map function to use it under the covers.

The additional IOMAP_F_BOUNDARY iomap flag indicates when iomap has
reached a "metadata boundary" and fetching the next mapping is likely to
incur an additional I/O.  This flag is used for setting the bh buffer
boundary flag.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2017-10-31 14:26:33 +01:00