Commit Graph

180 Commits

Author SHA1 Message Date
Mauro Carvalho Chehab
2bf31d9442 jbd2: fix kernel-doc markups
Kernel-doc markup should use this format:
        identifier - description

They should not have any type before that, as otherwise
the parser won't do the right thing.

Also, some identifiers have different names between their
prototypes and the kernel-doc markup.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/72f5c6628f5f278d67625f60893ffbc2ca28d46e.1605521731.git.mchehab+huawei@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-11-19 22:38:29 -05:00
Theodore Ts'o
05d5233df8 jbd2: fix up sparse warnings in checkpoint code
Add missing __acquires() and __releases() annotations.  Also, in an
"this should never happen" WARN_ON check, if it *does* actually
happen, we need to release j_state_lock since this function is always
supposed to release that lock.  Otherwise, things will quickly grind
to a halt after the WARN_ON trips.

Fixes: 96f1e09745 ("jbd2: avoid long hold times of j_state_lock...")
Cc: stable@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-11-07 00:09:08 -05:00
zhangyi (F)
529a781ee0 jbd2: remove unused parameter in jbd2_journal_try_to_free_buffers()
Parameter gfp_mask in jbd2_journal_try_to_free_buffers() is no longer
used after commit <536fc240e7147> ("jbd2: clean up
jbd2_journal_try_to_free_buffers()"), so just remove it.

Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20200620025427.1756360-6-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-08-07 14:12:35 -04:00
zhangyi (F)
c044f3d836 jbd2: abort journal if free a async write error metadata buffer
If we free a metadata buffer which has been failed to async write out
in the background, the jbd2 checkpoint procedure will not detect this
failure in jbd2_log_do_checkpoint(), so it may lead to filesystem
inconsistency after cleanup journal tail. This patch abort the journal
if free a buffer has write_io_error flag to prevent potential further
inconsistency.

Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20200620025427.1756360-5-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-08-07 14:12:34 -04:00
Lukas Czerner
24dc986491 jbd2: make sure jh have b_transaction set in refile/unfile_buffer
Callers of __jbd2_journal_unfile_buffer() and
__jbd2_journal_refile_buffer() assume that the b_transaction is set. In
fact if it's not, we can end up with journal_head refcounting errors
leading to crash much later that might be very hard to track down. Add
asserts to make sure that is the case.

We also make sure that b_next_transaction is NULL in
__jbd2_journal_unfile_buffer() since the callers expect that as well and
we should not get into that stage in this state anyway, leading to
problems later on if we do.

Tested with fstests.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200617092549.6712-1-lczerner@redhat.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-08-06 00:11:15 -04:00
Jan Kara
14ff628630 jbd2: avoid leaking transaction credits when unreserving handle
When reserved transaction handle is unused, we subtract its reserved
credits in __jbd2_journal_unreserve_handle() called from
jbd2_journal_stop(). However this function forgets to remove reserved
credits from transaction->t_outstanding_credits and thus the transaction
space that was reserved remains effectively leaked. The leaked
transaction space can be quite significant in some cases and leads to
unnecessarily small transactions and thus reducing throughput of the
journalling machinery. E.g. fsmark workload creating lots of 4k files
was observed to have about 20% lower throughput due to this when ext4 is
mounted with dioread_nolock mount option.

Subtract reserved credits from t_outstanding_credits as well.

CC: stable@vger.kernel.org
Fixes: 8f7d89f368 ("jbd2: transaction reservation support")
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200520133119.1383-3-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-06-03 23:16:53 -04:00
Qian Cai
6c5d911249 jbd2: fix data races at struct journal_head
journal_head::b_transaction and journal_head::b_next_transaction could
be accessed concurrently as noticed by KCSAN,

 LTP: starting fsync04
 /dev/zero: Can't open blockdev
 EXT4-fs (loop0): mounting ext3 file system using the ext4 subsystem
 EXT4-fs (loop0): mounted filesystem with ordered data mode. Opts: (null)
 ==================================================================
 BUG: KCSAN: data-race in __jbd2_journal_refile_buffer [jbd2] / jbd2_write_access_granted [jbd2]

 write to 0xffff99f9b1bd0e30 of 8 bytes by task 25721 on cpu 70:
  __jbd2_journal_refile_buffer+0xdd/0x210 [jbd2]
  __jbd2_journal_refile_buffer at fs/jbd2/transaction.c:2569
  jbd2_journal_commit_transaction+0x2d15/0x3f20 [jbd2]
  (inlined by) jbd2_journal_commit_transaction at fs/jbd2/commit.c:1034
  kjournald2+0x13b/0x450 [jbd2]
  kthread+0x1cd/0x1f0
  ret_from_fork+0x27/0x50

 read to 0xffff99f9b1bd0e30 of 8 bytes by task 25724 on cpu 68:
  jbd2_write_access_granted+0x1b2/0x250 [jbd2]
  jbd2_write_access_granted at fs/jbd2/transaction.c:1155
  jbd2_journal_get_write_access+0x2c/0x60 [jbd2]
  __ext4_journal_get_write_access+0x50/0x90 [ext4]
  ext4_mb_mark_diskspace_used+0x158/0x620 [ext4]
  ext4_mb_new_blocks+0x54f/0xca0 [ext4]
  ext4_ind_map_blocks+0xc79/0x1b40 [ext4]
  ext4_map_blocks+0x3b4/0x950 [ext4]
  _ext4_get_block+0xfc/0x270 [ext4]
  ext4_get_block+0x3b/0x50 [ext4]
  __block_write_begin_int+0x22e/0xae0
  __block_write_begin+0x39/0x50
  ext4_write_begin+0x388/0xb50 [ext4]
  generic_perform_write+0x15d/0x290
  ext4_buffered_write_iter+0x11f/0x210 [ext4]
  ext4_file_write_iter+0xce/0x9e0 [ext4]
  new_sync_write+0x29c/0x3b0
  __vfs_write+0x92/0xa0
  vfs_write+0x103/0x260
  ksys_write+0x9d/0x130
  __x64_sys_write+0x4c/0x60
  do_syscall_64+0x91/0xb05
  entry_SYSCALL_64_after_hwframe+0x49/0xbe

 5 locks held by fsync04/25724:
  #0: ffff99f9911093f8 (sb_writers#13){.+.+}, at: vfs_write+0x21c/0x260
  #1: ffff99f9db4c0348 (&sb->s_type->i_mutex_key#15){+.+.}, at: ext4_buffered_write_iter+0x65/0x210 [ext4]
  #2: ffff99f5e7dfcf58 (jbd2_handle){++++}, at: start_this_handle+0x1c1/0x9d0 [jbd2]
  #3: ffff99f9db4c0168 (&ei->i_data_sem){++++}, at: ext4_map_blocks+0x176/0x950 [ext4]
  #4: ffffffff99086b40 (rcu_read_lock){....}, at: jbd2_write_access_granted+0x4e/0x250 [jbd2]
 irq event stamp: 1407125
 hardirqs last  enabled at (1407125): [<ffffffff980da9b7>] __find_get_block+0x107/0x790
 hardirqs last disabled at (1407124): [<ffffffff980da8f9>] __find_get_block+0x49/0x790
 softirqs last  enabled at (1405528): [<ffffffff98a0034c>] __do_softirq+0x34c/0x57c
 softirqs last disabled at (1405521): [<ffffffff97cc67a2>] irq_exit+0xa2/0xc0

 Reported by Kernel Concurrency Sanitizer on:
 CPU: 68 PID: 25724 Comm: fsync04 Tainted: G L 5.6.0-rc2-next-20200221+ #7
 Hardware name: HPE ProLiant DL385 Gen10/ProLiant DL385 Gen10, BIOS A40 07/10/2019

The plain reads are outside of jh->b_state_lock critical section which result
in data races. Fix them by adding pairs of READ|WRITE_ONCE().

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Qian Cai <cai@lca.pw>
Link: https://lore.kernel.org/r/20200222043111.2227-1-cai@lca.pw
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-02-29 13:40:02 -05:00
wangyan
8eedabfd66 jbd2: fix ocfs2 corrupt when clearing block group bits
I found a NULL pointer dereference in ocfs2_block_group_clear_bits().
The running environment:
	kernel version: 4.19
	A cluster with two nodes, 5 luns mounted on two nodes, and do some
	file operations like dd/fallocate/truncate/rm on every lun with storage
	network disconnection.

The fallocate operation on dm-23-45 caused an null pointer dereference.

The information of NULL pointer dereference as follows:
	[577992.878282] JBD2: Error -5 detected when updating journal superblock for dm-23-45.
	[577992.878290] Aborting journal on device dm-23-45.
	...
	[577992.890778] JBD2: Error -5 detected when updating journal superblock for dm-24-46.
	[577992.890908] __journal_remove_journal_head: freeing b_committed_data
	[577992.890916] (fallocate,88392,52):ocfs2_extend_trans:474 ERROR: status = -30
	[577992.890918] __journal_remove_journal_head: freeing b_committed_data
	[577992.890920] (fallocate,88392,52):ocfs2_rotate_tree_right:2500 ERROR: status = -30
	[577992.890922] __journal_remove_journal_head: freeing b_committed_data
	[577992.890924] (fallocate,88392,52):ocfs2_do_insert_extent:4382 ERROR: status = -30
	[577992.890928] (fallocate,88392,52):ocfs2_insert_extent:4842 ERROR: status = -30
	[577992.890928] __journal_remove_journal_head: freeing b_committed_data
	[577992.890930] (fallocate,88392,52):ocfs2_add_clusters_in_btree:4947 ERROR: status = -30
	[577992.890933] __journal_remove_journal_head: freeing b_committed_data
	[577992.890939] __journal_remove_journal_head: freeing b_committed_data
	[577992.890949] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020
	[577992.890950] Mem abort info:
	[577992.890951]   ESR = 0x96000004
	[577992.890952]   Exception class = DABT (current EL), IL = 32 bits
	[577992.890952]   SET = 0, FnV = 0
	[577992.890953]   EA = 0, S1PTW = 0
	[577992.890954] Data abort info:
	[577992.890955]   ISV = 0, ISS = 0x00000004
	[577992.890956]   CM = 0, WnR = 0
	[577992.890958] user pgtable: 4k pages, 48-bit VAs, pgdp = 00000000f8da07a9
	[577992.890960] [0000000000000020] pgd=0000000000000000
	[577992.890964] Internal error: Oops: 96000004 [#1] SMP
	[577992.890965] Process fallocate (pid: 88392, stack limit = 0x00000000013db2fd)
	[577992.890968] CPU: 52 PID: 88392 Comm: fallocate Kdump: loaded Tainted: G        W  OE     4.19.36 #1
	[577992.890969] Hardware name: Huawei TaiShan 2280 V2/BC82AMDD, BIOS 0.98 08/25/2019
	[577992.890971] pstate: 60400009 (nZCv daif +PAN -UAO)
	[577992.891054] pc : _ocfs2_free_suballoc_bits+0x63c/0x968 [ocfs2]
	[577992.891082] lr : _ocfs2_free_suballoc_bits+0x618/0x968 [ocfs2]
	[577992.891084] sp : ffff0000c8e2b810
	[577992.891085] x29: ffff0000c8e2b820 x28: 0000000000000000
	[577992.891087] x27: 00000000000006f3 x26: ffffa07957b02e70
	[577992.891089] x25: ffff807c59d50000 x24: 00000000000006f2
	[577992.891091] x23: 0000000000000001 x22: ffff807bd39abc30
	[577992.891093] x21: ffff0000811d9000 x20: ffffa07535d6a000
	[577992.891097] x19: ffff000001681638 x18: ffffffffffffffff
	[577992.891098] x17: 0000000000000000 x16: ffff000080a03df0
	[577992.891100] x15: ffff0000811d9708 x14: 203d207375746174
	[577992.891101] x13: 73203a524f525245 x12: 20373439343a6565
	[577992.891103] x11: 0000000000000038 x10: 0101010101010101
	[577992.891106] x9 : ffffa07c68a85d70 x8 : 7f7f7f7f7f7f7f7f
	[577992.891109] x7 : 0000000000000000 x6 : 0000000000000080
	[577992.891110] x5 : 0000000000000000 x4 : 0000000000000002
	[577992.891112] x3 : ffff000001713390 x2 : 2ff90f88b1c22f00
	[577992.891114] x1 : ffff807bd39abc30 x0 : 0000000000000000
	[577992.891116] Call trace:
	[577992.891139]  _ocfs2_free_suballoc_bits+0x63c/0x968 [ocfs2]
	[577992.891162]  _ocfs2_free_clusters+0x100/0x290 [ocfs2]
	[577992.891185]  ocfs2_free_clusters+0x50/0x68 [ocfs2]
	[577992.891206]  ocfs2_add_clusters_in_btree+0x198/0x5e0 [ocfs2]
	[577992.891227]  ocfs2_add_inode_data+0x94/0xc8 [ocfs2]
	[577992.891248]  ocfs2_extend_allocation+0x1bc/0x7a8 [ocfs2]
	[577992.891269]  ocfs2_allocate_extents+0x14c/0x338 [ocfs2]
	[577992.891290]  __ocfs2_change_file_space+0x3f8/0x610 [ocfs2]
	[577992.891309]  ocfs2_fallocate+0xe4/0x128 [ocfs2]
	[577992.891316]  vfs_fallocate+0x11c/0x250
	[577992.891317]  ksys_fallocate+0x54/0x88
	[577992.891319]  __arm64_sys_fallocate+0x28/0x38
	[577992.891323]  el0_svc_common+0x78/0x130
	[577992.891325]  el0_svc_handler+0x38/0x78
	[577992.891327]  el0_svc+0x8/0xc

My analysis process as follows:
ocfs2_fallocate
  __ocfs2_change_file_space
    ocfs2_allocate_extents
      ocfs2_extend_allocation
        ocfs2_add_inode_data
          ocfs2_add_clusters_in_btree
            ocfs2_insert_extent
              ocfs2_do_insert_extent
                ocfs2_rotate_tree_right
                  ocfs2_extend_rotate_transaction
                    ocfs2_extend_trans
                      jbd2_journal_restart
                        jbd2__journal_restart
                          /* handle->h_transaction is NULL,
                           * is_handle_aborted(handle) is true
                           */
                          handle->h_transaction = NULL;
                          start_this_handle
                            return -EROFS;
            ocfs2_free_clusters
              _ocfs2_free_clusters
                _ocfs2_free_suballoc_bits
                  ocfs2_block_group_clear_bits
                    ocfs2_journal_access_gd
                      __ocfs2_journal_access
                        jbd2_journal_get_undo_access
                          /* I think jbd2_write_access_granted() will
                           * return true, because do_get_write_access()
                           * will return -EROFS.
                           */
                          if (jbd2_write_access_granted(...)) return 0;
                          do_get_write_access
                            /* handle->h_transaction is NULL, it will
                             * return -EROFS here, so do_get_write_access()
                             * was not called.
                             */
                            if (is_handle_aborted(handle)) return -EROFS;
                    /* bh2jh(group_bh) is NULL, caused NULL
                       pointer dereference */
                    undo_bg = (struct ocfs2_group_desc *)
                                bh2jh(group_bh)->b_committed_data;

If handle->h_transaction == NULL, then jbd2_write_access_granted()
does not really guarantee that journal_head will stay around,
not even speaking of its b_committed_data. The bh2jh(group_bh)
can be removed after ocfs2_journal_access_gd() and before call
"bh2jh(group_bh)->b_committed_data". So, we should move
is_handle_aborted() check from do_get_write_access() into
jbd2_journal_get_undo_access() and jbd2_journal_get_write_access()
before the call to jbd2_write_access_granted().

Link: https://lore.kernel.org/r/f72a623f-b3f1-381a-d91d-d22a1c83a336@huawei.com
Signed-off-by: Yan Wang <wangyan122@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jun Piao <piaojun@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@kernel.org
2020-02-21 19:32:07 -05:00
zhangyi (F)
6a66a7ded1 jbd2: move the clearing of b_modified flag to the journal_unmap_buffer()
There is no need to delay the clearing of b_modified flag to the
transaction committing time when unmapping the journalled buffer, so
just move it to the journal_unmap_buffer().

Link: https://lore.kernel.org/r/20200213063821.30455-2-yi.zhang@huawei.com
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
2020-02-13 12:06:17 -05:00
Shijie Luo
8d6ce13679 ext4,jbd2: fix comment and code style
Fix comment and remove unneccessary blank.

Signed-off-by: Shijie Luo <luoshijie1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200123064325.36358-1-luoshijie1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-01-25 02:24:53 -05:00
wangyan
0c1cba6cca jbd2: delete the duplicated words in the comments
Delete the duplicated words "is" in the comments

Signed-off-by: Yan Wang <wangyan122@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/12087f77-ab4d-c7ba-53b4-893dbf0026f0@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-01-25 02:23:29 -05:00
Linus Torvalds
50b8b3f85a This merge window saw the the following new featuers added to ext4:
* Direct I/O via iomap (required the iomap-for-next branch from Darrick
    as a prereq).
  * Support for using dioread-nolock where the block size < page size.
  * Support for encryption for file systems where the block size < page size.
  * Rework of journal credits handling so a revoke-heavy workload will
    not cause the journal to run out of space.
  * Replace bit-spinlocks with spinlocks in jbd2
 
 Also included were some bug fixes and cleanups, mostly to clean up
 corner cases from fuzzed file systems and error path handling.
 -----BEGIN PGP SIGNATURE-----
 
 iQEzBAABCAAdFiEEK2m5VNv+CHkogTfJ8vlZVpUNgaMFAl3dHxoACgkQ8vlZVpUN
 gaMZswf5AbtQhTEJDXO7Pc1ull38GIGFgAv7uAth0TymLC3h1/FEYWW0crEPFsDr
 1Eei55UUVOYrMMUKQ4P7wlLX0cIh3XDPMWnRFuqBoV5/ZOsH/ZSbkY//TG2Xze/v
 9wXIH/RKQnzbRtXffJ1+DnvmXJk+HFm1R1gjl0nfyUXGrnlSfqJxhLSczyd6bJJq
 ehi/tso5UC/4EQsAIdWp7VWsAdaHcZ7ogHqDoy8dXpM1equ408iml7VlKr8R+Nr7
 5ANpCISXChSlLLYm0NYN5vhO8upF5uDxWLdCtxVPL5kFdM2m/ELjXw9h9C+78l7C
 EWJGlGlxvx07Px+e+bfStEsoixpWBg==
 =0eko
 -----END PGP SIGNATURE-----

Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
 "This merge window saw the the following new featuers added to ext4:

   - Direct I/O via iomap (required the iomap-for-next branch from
     Darrick as a prereq).

   - Support for using dioread-nolock where the block size < page size.

   - Support for encryption for file systems where the block size < page
     size.

   - Rework of journal credits handling so a revoke-heavy workload will
     not cause the journal to run out of space.

   - Replace bit-spinlocks with spinlocks in jbd2

  Also included were some bug fixes and cleanups, mostly to clean up
  corner cases from fuzzed file systems and error path handling"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (59 commits)
  ext4: work around deleting a file with i_nlink == 0 safely
  ext4: add more paranoia checking in ext4_expand_extra_isize handling
  jbd2: make jbd2_handle_buffer_credits() handle reserved handles
  ext4: fix a bug in ext4_wait_for_tail_page_commit
  ext4: bio_alloc with __GFP_DIRECT_RECLAIM never fails
  ext4: code cleanup for get_next_id
  ext4: fix leak of quota reservations
  ext4: remove unused variable warning in parse_options()
  ext4: Enable encryption for subpage-sized blocks
  fs/buffer.c: support fscrypt in block_read_full_page()
  ext4: Add error handling for io_end_vec struct allocation
  jbd2: Fine tune estimate of necessary descriptor blocks
  jbd2: Provide trace event for handle restarts
  ext4: Reserve revoke credits for freed blocks
  jbd2: Make credit checking more strict
  jbd2: Rename h_buffer_credits to h_total_credits
  jbd2: Reserve space for revoke descriptor blocks
  jbd2: Drop jbd2_space_needed()
  jbd2: Account descriptor blocks into t_outstanding_credits
  jbd2: Factor out common parts of stopping and restarting a handle
  ...
2019-11-30 10:53:02 -08:00
Theodore Ts'o
a6d4040846 Merge branch 'jk/jbd2-revoke-overflow' 2019-11-05 16:02:20 -05:00
Jan Kara
19014d6971 jbd2: Fine tune estimate of necessary descriptor blocks
Currently we reserve j_max_transaction_buffers / 32 for transaction
descriptor blocks. Now that revoke descriptors are accounted for
separately this estimate is unnecessarily high and we can actually
compute much tighter estimate. In the common case of 32k journal blocks
and 4k blocksize this actually reduces the amount of reserved descriptor
blocks from 256 to ~25 which allows us to fit more real data into a
transaction.

Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-25-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-11-05 16:00:49 -05:00
Jan Kara
0094f981bb jbd2: Provide trace event for handle restarts
Provide trace event for handle restarts to ease debugging.

Reviewed-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-24-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-11-05 16:00:49 -05:00
Jan Kara
d090707eda jbd2: Make credit checking more strict
Make checking of available credits in jbd2_journal_dirty_metadata() more
strict. There should be always enough credits in the handle to write all
potential revoke descriptors. Also we warn in case there are not enough
credits since this is a bug in the filesystem.

Reviewed-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-22-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-11-05 16:00:49 -05:00
Jan Kara
933f1c1e0b jbd2: Rename h_buffer_credits to h_total_credits
The credit counter now contains both buffer and revoke descriptor block
credits. Rename to counter to h_total_credits to reflect that. No
functional change.

Reviewed-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-21-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-11-05 16:00:48 -05:00
Jan Kara
fdc3ef882a jbd2: Reserve space for revoke descriptor blocks
Extend functions for starting, extending, and restarting transaction
handles to take number of revoke records handle must be able to
accommodate. These functions then make sure transaction has enough
credits to be able to store resulting revoke descriptor blocks. Also
revoke code tracks number of revoke records created by a handle to catch
situation where some place didn't reserve enough space for revoke
records. Similarly to standard transaction credits, space for unused
reserved revoke records is released when the handle is stopped.

On the ext4 side we currently take a simplistic approach of reserving
space for 1024 revoke records for any transaction. This grows amount of
credits reserved for each handle only by a few and is enough for any
normal workload so that we don't hit warnings in jbd2. We will refine
the logic in following commits.

Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-20-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-11-05 16:00:48 -05:00
Jan Kara
77444ac4f9 jbd2: Drop jbd2_space_needed()
The function is now just a trivial wrapper returning
journal->j_max_transaction_buffers. Drop it.

Reviewed-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-19-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-11-05 16:00:48 -05:00
Jan Kara
9f356e5a4f jbd2: Account descriptor blocks into t_outstanding_credits
Currently, journal descriptor blocks were not accounted in
transaction->t_outstanding_credits and we were just leaving some slack
space in the journal for them (in jbd2_log_space_left() and
jbd2_space_needed()). This is making proper accounting (and reservation
we want to add) of descriptor blocks difficult so switch to accounting
descriptor blocks in transaction->t_outstanding_credits and just reserve
the same amount of credits in t_outstanding credits for journal
descriptor blocks when creating transaction.

Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-18-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-11-05 16:00:48 -05:00
Jan Kara
ec8b6f600e jbd2: Factor out common parts of stopping and restarting a handle
jbd2__journal_restart() has quite some code that is common with
jbd2_journal_stop(). Factor this functionality into stop_this_handle()
helper and use it from both functions. Note that this also drops
t_handle_lock protection from jbd2__journal_restart() as
jbd2_journal_stop() does the same thing without it.

Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-17-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-11-05 16:00:48 -05:00
Jan Kara
5559b2d81b jbd2: Drop pointless wakeup from jbd2_journal_stop()
When we drop last handle from a transaction and journal->j_barrier_count
> 0, jbd2_journal_stop() wakes up journal->j_wait_transaction_locked
wait queue. This looks pointless - wait for outstanding handles always
happens on journal->j_wait_updates waitqueue.
journal->j_wait_transaction_locked is used to wait for transaction state
changes and by start_this_handle() for waiting until
journal->j_barrier_count drops to 0. The first case is clearly
irrelevant here since only jbd2 thread changes transaction state. The
second case looks related but jbd2_journal_unlock_updates() is
responsible for the wakeup in this case. So just drop the wakeup.

Reviewed-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-16-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-11-05 16:00:48 -05:00
Jan Kara
150549ed2f jbd2: Drop pointless check from jbd2_journal_stop()
If a transaction is larger than journal->j_max_transaction_buffers, that
is a bug and not a trigger for transaction commit. Also the very next
attempt to start new handle will start transaction commit anyway. So
just remove the pointless check. Arguably, we could start transaction
commit whenever the transaction size is *close* to
journal->j_max_transaction_buffers. This has a potential to reduce
latency of the next jbd2_journal_start() at the cost of somewhat smaller
transactions. However for this to have any effect, it would mean that
there isn't someone already waiting in jbd2_journal_start() which means
metadata load for the fs is pretty light anyway so probably this
optimization is not worth it.

Reviewed-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-15-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-11-05 16:00:48 -05:00
Jan Kara
dfaf5ffda2 jbd2: Reorganize jbd2_journal_stop()
Move code in jbd2_journal_stop() around a bit. It removes some
unnecessary code duplication and will make factoring out parts common
with jbd2__journal_restart() easier.

Reviewed-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-14-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-11-05 16:00:48 -05:00
Thomas Gleixner
464170647b jbd2: Make state lock a spinlock
Bit-spinlocks are problematic on PREEMPT_RT if functions which might sleep
on RT, e.g. spin_lock(), alloc/free(), are invoked inside the lock held
region because bit spinlocks disable preemption even on RT.

A first attempt was to replace state lock with a spinlock placed in struct
buffer_head and make the locking conditional on PREEMPT_RT and
DEBUG_BIT_SPINLOCKS.

Jan pointed out that there is a 4 byte hole in struct journal_head where a
regular spinlock fits in and he would not object to convert the state lock
to a spinlock unconditionally.

Aside of solving the RT problem, this also gains lockdep coverage for the
journal head state lock (bit-spinlocks are not covered by lockdep as it's
hard to fit a lockdep map into a single bit).

The trivial change would have been to convert the jbd_*lock_bh_state()
inlines, but that comes with the downside that these functions take a
buffer head pointer which needs to be converted to a journal head pointer
which adds another level of indirection.

As almost all functions which use this lock have a journal head pointer
readily available, it makes more sense to remove the lock helper inlines
and write out spin_*lock() at all call sites.

Fixup all locking comments as well.

Suggested-by: Jan Kara <jack@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jan Kara <jack@suse.com>
Cc: linux-ext4@vger.kernel.org
Link: https://lore.kernel.org/r/20190809124233.13277-7-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-21 09:16:46 -04:00
Jan Kara
2e710ff03f jbd2: Don't call __bforget() unnecessarily
jbd2_journal_forget() jumps to 'not_jbd' branch which calls __bforget()
in cases where the buffer is clean which is pointless. In case of failed
assertion, it can be even argued that it is safer not to touch buffer's
dirty bits. Also logically it makes more sense to just jump to 'drop'
and that will make logic also simpler when we switch bh_state_lock to a
spinlock.

Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20190809124233.13277-6-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-21 09:16:46 -04:00
Jan Kara
6d69843e5d jbd2: Drop unnecessary branch from jbd2_journal_forget()
We have cleared both dirty & jbddirty bits from the bh. So there's no
difference between bforget() and brelse(). Thus there's no point jumping
to no_jbd branch.

Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20190809124233.13277-5-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-21 09:16:46 -04:00
Jan Kara
93108ebb84 jbd2: Move dropping of jh reference out of un/re-filing functions
__jbd2_journal_unfile_buffer() and __jbd2_journal_refile_buffer() drop
transaction's jh reference when they remove jh from a transaction. This
will be however inconvenient once we move state lock into journal_head
itself as we still need to unlock it and we'd need to grab jh reference
just for that. Move dropping of jh reference out of these functions into
the few callers.

Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20190809124233.13277-4-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-21 09:16:46 -04:00
Thomas Gleixner
d84560f74d jbd2: Simplify journal_unmap_buffer()
journal_unmap_buffer() checks first whether the buffer head is a journal.
If so it takes locks and then invokes jbd2_journal_grab_journal_head()
followed by another check whether this is journal head buffer.

The double checking is pointless.

Replace the initial check with jbd2_journal_grab_journal_head() which
alredy checks whether the buffer head is actually a journal.

Allows also early access to the journal head pointer for the upcoming
conversion of state lock to a regular spinlock.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: linux-ext4@vger.kernel.org
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20190809124233.13277-2-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-21 09:16:45 -04:00
Qian Cai
5facae4f35 locking/lockdep: Remove unused @nested argument from lock_release()
Since the following commit:

  b4adfe8e05 ("locking/lockdep: Remove unused argument in __lock_release")

@nested is no longer used in lock_release(), so remove it from all
lock_release() calls and friends.

Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: airlied@linux.ie
Cc: akpm@linux-foundation.org
Cc: alexander.levin@microsoft.com
Cc: daniel@iogearbox.net
Cc: davem@davemloft.net
Cc: dri-devel@lists.freedesktop.org
Cc: duyuyang@gmail.com
Cc: gregkh@linuxfoundation.org
Cc: hannes@cmpxchg.org
Cc: intel-gfx@lists.freedesktop.org
Cc: jack@suse.com
Cc: jlbec@evilplan.or
Cc: joonas.lahtinen@linux.intel.com
Cc: joseph.qi@linux.alibaba.com
Cc: jslaby@suse.com
Cc: juri.lelli@redhat.com
Cc: maarten.lankhorst@linux.intel.com
Cc: mark@fasheh.com
Cc: mhocko@kernel.org
Cc: mripard@kernel.org
Cc: ocfs2-devel@oss.oracle.com
Cc: rodrigo.vivi@intel.com
Cc: sean@poorly.run
Cc: st@kernel.org
Cc: tj@kernel.org
Cc: tytso@mit.edu
Cc: vdavydov.dev@gmail.com
Cc: vincent.guittot@linaro.org
Cc: viro@zeniv.linux.org.uk
Link: https://lkml.kernel.org/r/1568909380-32199-1-git-send-email-cai@lca.pw
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-09 12:46:10 +02:00
Joseph Qi
963abb9aeb jbd2: remove jbd2_journal_inode_add_[write|wait]
Since ext4/ocfs2 are using jbd2_inode dirty range scoping APIs now,
jbd2_journal_inode_add_[write|wait] are not used any more, remove them.

Link: http://lkml.kernel.org/r/1562977611-8412-2-git-send-email-joseph.qi@linux.alibaba.com
Signed-off-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: Ross Zwisler <zwisler@google.com>
Acked-by: Changwei Ge <chge@linux.alibaba.com>
Cc: Gang He <ghe@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Joseph Qi <jiangqi903@gmail.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-09-24 15:54:07 -07:00
Xiaoguang Wang
4c273352bb jbd2: add missing tracepoint for reserved handle
This issue was found when I use ebpf to trace every jbd2
handle's running info in dioread_nolock case.

Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-08-24 23:10:17 -04:00
Ross Zwisler
6ba0e7dc64 jbd2: introduce jbd2_inode dirty range scoping
Currently both journal_submit_inode_data_buffers() and
journal_finish_inode_data_buffers() operate on the entire address space
of each of the inodes associated with a given journal entry.  The
consequence of this is that if we have an inode where we are constantly
appending dirty pages we can end up waiting for an indefinite amount of
time in journal_finish_inode_data_buffers() while we wait for all the
pages under writeback to be written out.

The easiest way to cause this type of workload is do just dd from
/dev/zero to a file until it fills the entire filesystem.  This can
cause journal_finish_inode_data_buffers() to wait for the duration of
the entire dd operation.

We can improve this situation by scoping each of the inode dirty ranges
associated with a given transaction.  We do this via the jbd2_inode
structure so that the scoping is contained within jbd2 and so that it
follows the lifetime and locking rules for that structure.

This allows us to limit the writeback & wait in
journal_submit_inode_data_buffers() and
journal_finish_inode_data_buffers() respectively to the dirty range for
a given struct jdb2_inode, keeping us from waiting forever if the inode
in question is still being appended to.

Signed-off-by: Ross Zwisler <zwisler@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@vger.kernel.org
2019-06-20 17:24:56 -04:00
Chengguang Xu
0d52154bb0 jbd2: fix potential double free
When failing from creating cache jbd2_inode_cache, we will destroy the
previously created cache jbd2_handle_cache twice.  This patch fixes
this by moving each cache initialization/destruction to its own
separate, individual function.

Signed-off-by: Chengguang Xu <cgxu519@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
2019-05-10 21:15:47 -04:00
Liu Song
0df6f46995 jbd2: jbd2_get_transaction does not need to return a value
In jbd2_get_transaction, a new transaction is initialized,
and set to the j_running_transaction. No need for a return
value, so remove it.

Also, adjust some comments to match the actual operation
of this function.

Signed-off-by: Liu Song <liu.song11@zte.com.cn>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2019-03-01 00:36:57 -05:00
zhangyi (F)
01215d3edb jbd2: fix compile warning when using JBUFFER_TRACE
The jh pointer may be used uninitialized in the two cases below and the
compiler complain about it when enabling JBUFFER_TRACE macro, fix them.

In file included from fs/jbd2/transaction.c:19:0:
fs/jbd2/transaction.c: In function ‘jbd2_journal_get_undo_access’:
./include/linux/jbd2.h:1637:38: warning: ‘jh’ is used uninitialized in this function [-Wuninitialized]
 #define JBUFFER_TRACE(jh, info) do { printk("%s: %d\n", __func__, jh->b_jcount);} while (0)
                                      ^
fs/jbd2/transaction.c:1219:23: note: ‘jh’ was declared here
  struct journal_head *jh;
                       ^
In file included from fs/jbd2/transaction.c:19:0:
fs/jbd2/transaction.c: In function ‘jbd2_journal_dirty_metadata’:
./include/linux/jbd2.h:1637:38: warning: ‘jh’ may be used uninitialized in this function [-Wmaybe-uninitialized]
 #define JBUFFER_TRACE(jh, info) do { printk("%s: %d\n", __func__, jh->b_jcount);} while (0)
                                      ^
fs/jbd2/transaction.c:1332:23: note: ‘jh’ was declared here
  struct journal_head *jh;
                       ^

Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
Reviewed-by: Jan Kara <jack@suse.cz>
2019-02-21 11:24:09 -05:00
zhangyi (F)
597599268e jbd2: discard dirty data when forgetting an un-journalled buffer
We do not unmap and clear dirty flag when forgetting a buffer without
journal or does not belongs to any transaction, so the invalid dirty
data may still be written to the disk later. It's fine if the
corresponding block is never used before the next mount, and it's also
fine that we invoke clean_bdev_aliases() related functions to unmap
the block device mapping when re-allocating such freed block as data
block. But this logic is somewhat fragile and risky that may lead to
data corruption if we forget to clean bdev aliases. So, It's better to
discard dirty data during forget time.

We have been already handled all the cases of forgetting journalled
buffer, this patch deal with the remaining two cases.

- buffer is not journalled yet,
- buffer is journalled but doesn't belongs to any transaction.

We invoke __bforget() instead of __brelese() when forgetting an
un-journalled buffer in jbd2_journal_forget(). After this patch we can
remove all clean_bdev_aliases() related calls in ext4.

Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2019-02-10 23:26:06 -05:00
zhangyi (F)
904cdbd41d jbd2: clear dirty flag when revoking a buffer from an older transaction
Now, we capture a data corruption problem on ext4 while we're truncating
an extent index block. Imaging that if we are revoking a buffer which
has been journaled by the committing transaction, the buffer's jbddirty
flag will not be cleared in jbd2_journal_forget(), so the commit code
will set the buffer dirty flag again after refile the buffer.

fsx                               kjournald2
                                  jbd2_journal_commit_transaction
jbd2_journal_revoke                commit phase 1~5...
 jbd2_journal_forget
   belongs to older transaction    commit phase 6
   jbddirty not clear               __jbd2_journal_refile_buffer
                                     __jbd2_journal_unfile_buffer
                                      test_clear_buffer_jbddirty
                                       mark_buffer_dirty

Finally, if the freed extent index block was allocated again as data
block by some other files, it may corrupt the file data after writing
cached pages later, such as during unmount time. (In general,
clean_bdev_aliases() related helpers should be invoked after
re-allocation to prevent the above corruption, but unfortunately we
missed it when zeroout the head of extra extent blocks in
ext4_ext_handle_unwritten_extents()).

This patch mark buffer as freed and set j_next_transaction to the new
transaction when it already belongs to the committing transaction in
jbd2_journal_forget(), so that commit code knows it should clear dirty
bits when it is done with the buffer.

This problem can be reproduced by xfstests generic/455 easily with
seeds (3246 3247 3248 3249).

Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@vger.kernel.org
2019-02-10 23:23:04 -05:00
Colin Ian King
561405f031 jbd2: clean up indentation issue, replace spaces with tab
There is a statement that is indented with spaces, replace it with
a tab.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2018-12-04 00:20:10 -05:00
Jan Kara
96f1e09745 jbd2: avoid long hold times of j_state_lock while committing a transaction
We can hold j_state_lock for writing at the beginning of
jbd2_journal_commit_transaction() for a rather long time (reportedly for
30 ms) due cleaning revoke bits of all revoked buffers under it. The
handling of revoke tables as well as cleaning of t_reserved_list, and
checkpoint lists does not need j_state_lock for anything. It is only
needed to prevent new handles from joining the transaction. Generally
T_LOCKED transaction state prevents new handles from joining the
transaction - except for reserved handles which have to allowed to join
while we wait for other handles to complete.

To prevent reserved handles from joining the transaction while cleaning
up lists, add new transaction state T_SWITCH and watch for it when
starting reserved handles. With this we can just drop the lock for
operations that don't need it.

Reported-and-tested-by: Adrian Hunter <adrian.hunter@intel.com>
Suggested-by: "Theodore Y. Ts'o" <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2018-12-03 23:16:07 -05:00
Theodore Ts'o
e09463f220 jbd2: don't mark block as modified if the handle is out of credits
Do not set the b_modified flag in block's journal head should not
until after we're sure that jbd2_journal_dirty_metadat() will not
abort with an error due to there not being enough space reserved in
the jbd2 handle.

Otherwise, future attempts to modify the buffer may lead a large
number of spurious errors and warnings.

This addresses CVE-2018-10883.

https://bugzilla.kernel.org/show_bug.cgi?id=200071

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
2018-06-16 20:21:45 -04:00
Wang Long
8bdd5b60e0 jbd2: remove NULL check before calling kmem_cache_destroy()
The kmem_cache_destroy() function already checks for null pointers, so
we can remove the check at the call site.

This patch also sets jbd2_handle_cache and jbd2_inode_cache to be NULL
after freeing them in jbd2_journal_destroy_handle_cache().

Signed-off-by: Wang Long <wanglong19@meituan.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2018-05-20 22:38:26 -04:00
Theodore Ts'o
b2569260d5 ext4: set h_journal if there is a failure starting a reserved handle
If ext4 tries to start a reserved handle via
jbd2_journal_start_reserved(), and the journal has been aborted, this
can result in a NULL pointer dereference.  This is because the fields
h_journal and h_transaction in the handle structure share the same
memory, via a union, so jbd2_journal_start_reserved() will clear
h_journal before calling start_this_handle().  If this function fails
due to an aborted handle, h_journal will still be NULL, and the call
to jbd2_journal_free_reserved() will pass a NULL journal to
sub_reserve_credits().

This can be reproduced by running "kvm-xfstests -c dioread_nolock
generic/475".

Cc: stable@kernel.org # 3.11
Fixes: 8f7d89f368 ("jbd2: transaction reservation support")
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Jan Kara <jack@suse.cz>
2018-04-18 11:49:31 -04:00
Tobin C. Harding
f69120ce6c jbd2: fix sphinx kernel-doc build warnings
Sphinx emits various (26) warnings when building make target 'htmldocs'.
Currently struct definitions contain duplicate documentation, some as
kernel-docs and some as standard c89 comments.  We can reduce
duplication while cleaning up the kernel docs.

Move all kernel-docs to right above each struct member.  Use the set of
all existing comments (kernel-doc and c89).  Add documentation for
missing struct members and function arguments.

Signed-off-by: Tobin C. Harding <me@tobin.cc>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2018-01-10 00:27:29 -05:00
Theodore Ts'o
f516676857 ext4: fix up remaining files with SPDX cleanups
A number of ext4 source files were skipped due because their copyright
permission statements didn't match the expected text used by the
automated conversion utilities.  I've added SPDX tags for the rest.

While looking at some of these files, I've noticed that we have quite
a bit of variation on the licenses that were used --- in particular
some of the Red Hat licenses on the jbd2 files use a GPL2+ license,
and we have some files that have a LGPL-2.1 license (which was quite
surprising).

I've not attempted to do any license changes.  Even if it is perfectly
legal to relicense to GPL 2.0-only for consistency's sake, that should
be done with ext4 developer community discussion.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-12-17 22:00:59 -05:00
Linus Torvalds
650fc870a2 There has been a fair amount of activity in the docs tree this time
around.  Highlights include:
 
  - Conversion of a bunch of security documentation into RST
 
  - The conversion of the remaining DocBook templates by The Amazing
    Mauro Machine.  We can now drop the entire DocBook build chain.
 
  - The usual collection of fixes and minor updates.
 -----BEGIN PGP SIGNATURE-----
 
 iQIcBAABAgAGBQJZWkGAAAoJEI3ONVYwIuV6rf0P/0B3JTiVPKS/WUx53+jzbAi4
 1BN7dmmuMxE1bWpgdEq+ac4aKxm07iAojuntuMj0qz/ZB1WARcmvEqqzI5i4wfq9
 5MrLduLkyuWfr4MOPseKJ2VK83p8nkMOiO7jmnBsilu7fE4nF+5YY9j4cVaArfMy
 cCQvAGjQzvej2eiWMGUSLHn4QFKh00aD7cwKyBVsJ08b27C9xL0J2LQyCDZ4yDgf
 37/MH3puEd3HX/4qAwLonIxT3xrIrrbDturqLU7OSKcWTtGZNrYyTFbwR3RQtqWd
 H8YZVg2Uyhzg9MYhkbQ2E5dEjUP4mkegcp6/JTINH++OOPpTbdTJgirTx7VTkSf1
 +kL8t7+Ayxd0FH3+77GJ5RMj8LUK6rj5cZfU5nClFQKWXP9UL3IelQ3Nl+SpdM8v
 ZAbR2KjKgH9KS6+cbIhgFYlvY+JgPkOVruwbIAc7wXVM3ibk1sWoBOFEujcbueWh
 yDpQv3l1UX0CKr3jnevJoW26LtEbGFtC7gSKZ+3btyeSBpWFGlii42KNycEGwUW0
 ezlwryDVHzyTUiKllNmkdK4v73mvPsZHEjgmme4afKAIiUilmcUF4XcqD86hISFT
 t+UJLA/zEU+0sJe26o2nK6GNJzmo4oCtVyxfhRe26Ojs1n80xlYgnZRfuIYdd31Z
 nwLBnwDCHAOyX91WXp9G
 =cVjZ
 -----END PGP SIGNATURE-----

Merge tag 'docs-4.13' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "There has been a fair amount of activity in the docs tree this time
  around. Highlights include:

   - Conversion of a bunch of security documentation into RST

   - The conversion of the remaining DocBook templates by The Amazing
     Mauro Machine. We can now drop the entire DocBook build chain.

   - The usual collection of fixes and minor updates"

* tag 'docs-4.13' of git://git.lwn.net/linux: (90 commits)
  scripts/kernel-doc: handle DECLARE_HASHTABLE
  Documentation: atomic_ops.txt is core-api/atomic_ops.rst
  Docs: clean up some DocBook loose ends
  Make the main documentation title less Geocities
  Docs: Use kernel-figure in vidioc-g-selection.rst
  Docs: fix table problems in ras.rst
  Docs: Fix breakage with Sphinx 1.5 and upper
  Docs: Include the Latex "ifthen" package
  doc/kokr/howto: Only send regression fixes after -rc1
  docs-rst: fix broken links to dynamic-debug-howto in kernel-parameters
  doc: Document suitability of IBM Verse for kernel development
  Doc: fix a markup error in coding-style.rst
  docs: driver-api: i2c: remove some outdated information
  Documentation: DMA API: fix a typo in a function name
  Docs: Insert missing space to separate link from text
  doc/ko_KR/memory-barriers: Update control-dependencies example
  Documentation, kbuild: fix typo "minimun" -> "minimum"
  docs: Fix some formatting issues in request-key.rst
  doc: ReSTify keys-trusted-encrypted.txt
  doc: ReSTify keys-request-key.txt
  ...
2017-07-03 21:13:25 -07:00
Tahsin Erdogan
b4709067ac jbd2: preserve original nofs flag during journal restart
When a transaction starts, start_this_handle() saves current
PF_MEMALLOC_NOFS value so that it can be restored at journal stop time.
Journal restart is a special case that calls start_this_handle() without
stopping the transaction. start_this_handle() isn't aware that the
original value is already stored so it overwrites it with current value.

For instance, a call sequence like below leaves PF_MEMALLOC_NOFS flag set
at the end:

  jbd2_journal_start()
  jbd2__journal_restart()
  jbd2_journal_stop()

Make jbd2__journal_restart() restore the original value before calling
start_this_handle().

Fixes: 81378da64d ("jbd2: mark the transaction context with the scope GFP_NOFS context")
Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2017-05-21 22:32:23 -04:00
Mauro Carvalho Chehab
df1b560a4a fs: jbd2: escape a string with special chars on a kernel-doc
kernel-doc will try to interpret a foo() string, except if
properly escaped.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-05-16 08:44:11 -03:00
Mauro Carvalho Chehab
91e4775d0f fs: jbd2: make jbd2_journal_start() kernel-doc parseable
kernel-doc script expects that a function documentation to
be just before the function, otherwise it will be ignored.

So, move the kernel-doc markup to the right place.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-05-16 08:44:09 -03:00
Michal Hocko
81378da64d jbd2: mark the transaction context with the scope GFP_NOFS context
now that we have memalloc_nofs_{save,restore} api we can mark the whole
transaction context as implicitly GFP_NOFS.  All allocations will
automatically inherit GFP_NOFS this way.  This means that we do not have
to mark any of those requests with GFP_NOFS and moreover all the
ext4_kv[mz]alloc(GFP_NOFS) are also safe now because even the hardcoded
GFP_KERNEL allocations deep inside the vmalloc will be NOFS now.

[akpm@linux-foundation.org: tweak comments]
Link: http://lkml.kernel.org/r/20170306131408.9828-7-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Chris Mason <clm@fb.com>
Cc: David Sterba <dsterba@suse.cz>
Cc: Brian Foster <bfoster@redhat.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Nikolay Borisov <nborisov@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-03 15:52:09 -07:00