Skip to content

K
Kernel

openeuler / Kernel
1 年多 前同步成功

通知 8
Star 0
Fork 0
K
Kernel
切换分支/标签
  1. 13 7月, 2022 2 次提交
  3. 10 7月, 2022 3 次提交
    • D
      xfs: use XFS_IFORK_Q to determine the presence of an xattr fork · e45d7cb2
      由 Darrick J. Wong 提交于 
      Modify xfs_ifork_ptr to return a NULL pointer if the caller asks for the
attribute fork but i_forkoff is zero.  This eliminates the ambiguity
between i_forkoff and i_af.if_present, which should make it easier to
understand the lifetime of attr forks.

While we're at it, remove the if_present checks around calls to
xfs_idestroy_fork and xfs_ifork_zap_attr since they can both handle attr
forks that have already been torn down.
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
      e45d7cb2
    • D
      xfs: make inode attribute forks a permanent part of struct xfs_inode · 2ed5b09b
      由 Darrick J. Wong 提交于 
      Syzkaller reported a UAF bug a while back:

==================================================================
BUG: KASAN: use-after-free in xfs_ilock_attr_map_shared+0xe3/0xf6 fs/xfs/xfs_inode.c:127
Read of size 4 at addr ffff88802cec919c by task syz-executor262/2958

CPU: 2 PID: 2958 Comm: syz-executor262 Not tainted
5.15.0-0.30.3-20220406_1406 #3
Hardware name: Red Hat KVM, BIOS 1.13.0-2.module+el8.3.0+7860+a7792d29
04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x82/0xa9 lib/dump_stack.c:106
 print_address_description.constprop.9+0x21/0x2d5 mm/kasan/report.c:256
 __kasan_report mm/kasan/report.c:442 [inline]
 kasan_report.cold.14+0x7f/0x11b mm/kasan/report.c:459
 xfs_ilock_attr_map_shared+0xe3/0xf6 fs/xfs/xfs_inode.c:127
 xfs_attr_get+0x378/0x4c2 fs/xfs/libxfs/xfs_attr.c:159
 xfs_xattr_get+0xe3/0x150 fs/xfs/xfs_xattr.c:36
 __vfs_getxattr+0xdf/0x13d fs/xattr.c:399
 cap_inode_need_killpriv+0x41/0x5d security/commoncap.c:300
 security_inode_need_killpriv+0x4c/0x97 security/security.c:1408
 dentry_needs_remove_privs.part.28+0x21/0x63 fs/inode.c:1912
 dentry_needs_remove_privs+0x80/0x9e fs/inode.c:1908
 do_truncate+0xc3/0x1e0 fs/open.c:56
 handle_truncate fs/namei.c:3084 [inline]
 do_open fs/namei.c:3432 [inline]
 path_openat+0x30ab/0x396d fs/namei.c:3561
 do_filp_open+0x1c4/0x290 fs/namei.c:3588
 do_sys_openat2+0x60d/0x98c fs/open.c:1212
 do_sys_open+0xcf/0x13c fs/open.c:1228
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3a/0x7e arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0x0
RIP: 0033:0x7f7ef4bb753d
Code: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48
89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73
01 c3 48 8b 0d 1b 79 2c 00 f7 d8 64 89 01 48
RSP: 002b:00007f7ef52c2ed8 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 0000000000404148 RCX: 00007f7ef4bb753d
RDX: 00007f7ef4bb753d RSI: 0000000000000000 RDI: 0000000020004fc0
RBP: 0000000000404140 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0030656c69662f2e
R13: 00007ffd794db37f R14: 00007ffd794db470 R15: 00007f7ef52c2fc0
 </TASK>

Allocated by task 2953:
 kasan_save_stack+0x19/0x38 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 __kasan_slab_alloc+0x68/0x7c mm/kasan/common.c:467
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook mm/slab.h:519 [inline]
 slab_alloc_node mm/slub.c:3213 [inline]
 slab_alloc mm/slub.c:3221 [inline]
 kmem_cache_alloc+0x11b/0x3eb mm/slub.c:3226
 kmem_cache_zalloc include/linux/slab.h:711 [inline]
 xfs_ifork_alloc+0x25/0xa2 fs/xfs/libxfs/xfs_inode_fork.c:287
 xfs_bmap_add_attrfork+0x3f2/0x9b1 fs/xfs/libxfs/xfs_bmap.c:1098
 xfs_attr_set+0xe38/0x12a7 fs/xfs/libxfs/xfs_attr.c:746
 xfs_xattr_set+0xeb/0x1a9 fs/xfs/xfs_xattr.c:59
 __vfs_setxattr+0x11b/0x177 fs/xattr.c:180
 __vfs_setxattr_noperm+0x128/0x5e0 fs/xattr.c:214
 __vfs_setxattr_locked+0x1d4/0x258 fs/xattr.c:275
 vfs_setxattr+0x154/0x33d fs/xattr.c:301
 setxattr+0x216/0x29f fs/xattr.c:575
 __do_sys_fsetxattr fs/xattr.c:632 [inline]
 __se_sys_fsetxattr fs/xattr.c:621 [inline]
 __x64_sys_fsetxattr+0x243/0x2fe fs/xattr.c:621
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3a/0x7e arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0x0

Freed by task 2949:
 kasan_save_stack+0x19/0x38 mm/kasan/common.c:38
 kasan_set_track+0x1c/0x21 mm/kasan/common.c:46
 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:360
 ____kasan_slab_free mm/kasan/common.c:366 [inline]
 ____kasan_slab_free mm/kasan/common.c:328 [inline]
 __kasan_slab_free+0xe2/0x10e mm/kasan/common.c:374
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1700 [inline]
 slab_free_freelist_hook mm/slub.c:1726 [inline]
 slab_free mm/slub.c:3492 [inline]
 kmem_cache_free+0xdc/0x3ce mm/slub.c:3508
 xfs_attr_fork_remove+0x8d/0x132 fs/xfs/libxfs/xfs_attr_leaf.c:773
 xfs_attr_sf_removename+0x5dd/0x6cb fs/xfs/libxfs/xfs_attr_leaf.c:822
 xfs_attr_remove_iter+0x68c/0x805 fs/xfs/libxfs/xfs_attr.c:1413
 xfs_attr_remove_args+0xb1/0x10d fs/xfs/libxfs/xfs_attr.c:684
 xfs_attr_set+0xf1e/0x12a7 fs/xfs/libxfs/xfs_attr.c:802
 xfs_xattr_set+0xeb/0x1a9 fs/xfs/xfs_xattr.c:59
 __vfs_removexattr+0x106/0x16a fs/xattr.c:468
 cap_inode_killpriv+0x24/0x47 security/commoncap.c:324
 security_inode_killpriv+0x54/0xa1 security/security.c:1414
 setattr_prepare+0x1a6/0x897 fs/attr.c:146
 xfs_vn_change_ok+0x111/0x15e fs/xfs/xfs_iops.c:682
 xfs_vn_setattr_size+0x5f/0x15a fs/xfs/xfs_iops.c:1065
 xfs_vn_setattr+0x125/0x2ad fs/xfs/xfs_iops.c:1093
 notify_change+0xae5/0x10a1 fs/attr.c:410
 do_truncate+0x134/0x1e0 fs/open.c:64
 handle_truncate fs/namei.c:3084 [inline]
 do_open fs/namei.c:3432 [inline]
 path_openat+0x30ab/0x396d fs/namei.c:3561
 do_filp_open+0x1c4/0x290 fs/namei.c:3588
 do_sys_openat2+0x60d/0x98c fs/open.c:1212
 do_sys_open+0xcf/0x13c fs/open.c:1228
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3a/0x7e arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0x0

The buggy address belongs to the object at ffff88802cec9188
 which belongs to the cache xfs_ifork of size 40
The buggy address is located 20 bytes inside of
 40-byte region [ffff88802cec9188, ffff88802cec91b0)
The buggy address belongs to the page:
page:00000000c3af36a1 refcount:1 mapcount:0 mapping:0000000000000000
index:0x0 pfn:0x2cec9
flags: 0xfffffc0000200(slab|node=0|zone=1|lastcpupid=0x1fffff)
raw: 000fffffc0000200 ffffea00009d2580 0000000600000006 ffff88801a9ffc80
raw: 0000000000000000 0000000080490049 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88802cec9080: fb fb fb fc fc fa fb fb fb fb fc fc fb fb fb fb
 ffff88802cec9100: fb fc fc fb fb fb fb fb fc fc fb fb fb fb fb fc
>ffff88802cec9180: fc fa fb fb fb fb fc fc fa fb fb fb fb fc fc fb
                            ^
 ffff88802cec9200: fb fb fb fb fc fc fb fb fb fb fb fc fc fb fb fb
 ffff88802cec9280: fb fb fc fc fa fb fb fb fb fc fc fa fb fb fb fb
==================================================================

The root cause of this bug is the unlocked access to xfs_inode.i_afp
from the getxattr code paths while trying to determine which ILOCK mode
to use to stabilize the xattr data.  Unfortunately, the VFS does not
acquire i_rwsem when vfs_getxattr (or listxattr) call into the
filesystem, which means that getxattr can race with a removexattr that's
tearing down the attr fork and crash:

xfs_attr_set:                          xfs_attr_get:
xfs_attr_fork_remove:                  xfs_ilock_attr_map_shared:

xfs_idestroy_fork(ip->i_afp);
kmem_cache_free(xfs_ifork_cache, ip->i_afp);

                                       if (ip->i_afp &&

ip->i_afp = NULL;

                                           xfs_need_iread_extents(ip->i_afp))
                                       <KABOOM>

ip->i_forkoff = 0;

Regrettably, the VFS is much more lax about i_rwsem and getxattr than
is immediately obvious -- not only does it not guarantee that we hold
i_rwsem, it actually doesn't guarantee that we *don't* hold it either.
The getxattr system call won't acquire the lock before calling XFS, but
the file capabilities code calls getxattr with and without i_rwsem held
to determine if the "security.capabilities" xattr is set on the file.

Fixing the VFS locking requires a treewide investigation into every code
path that could touch an xattr and what i_rwsem state it expects or sets
up.  That could take years or even prove impossible; fortunately, we
can fix this UAF problem inside XFS.

An earlier version of this patch used smp_wmb in xfs_attr_fork_remove to
ensure that i_forkoff is always zeroed before i_afp is set to null and
changed the read paths to use smp_rmb before accessing i_forkoff and
i_afp, which avoided these UAF problems.  However, the patch author was
too busy dealing with other problems in the meantime, and by the time he
came back to this issue, the situation had changed a bit.

On a modern system with selinux, each inode will always have at least
one xattr for the selinux label, so it doesn't make much sense to keep
incurring the extra pointer dereference.  Furthermore, Allison's
upcoming parent pointer patchset will also cause nearly every inode in
the filesystem to have extended attributes.  Therefore, make the inode
attribute fork structure part of struct xfs_inode, at a cost of 40 more
bytes.

This patch adds a clunky if_present field where necessary to maintain
the existing logic of xattr fork null pointer testing in the existing
codebase.  The next patch switches the logic over to XFS_IFORK_Q and it
all goes away.
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
      2ed5b09b
    • D
      xfs: convert XFS_IFORK_PTR to a static inline helper · 732436ef
      由 Darrick J. Wong 提交于 
      We're about to make this logic do a bit more, so convert the macro to a
static inline function for better typechecking and fewer shouty macros.
No functional changes here.
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
      732436ef
  5. 21 4月, 2022 1 次提交
  7. 11 4月, 2022 1 次提交
  9. 15 3月, 2022 1 次提交
  11. 02 2月, 2022 2 次提交
  13. 25 11月, 2021 1 次提交
  15. 23 10月, 2021 2 次提交
  17. 20 8月, 2021 1 次提交
  19. 07 8月, 2021 2 次提交
    • D
      xfs: per-cpu deferred inode inactivation queues · ab23a776
      由 Dave Chinner 提交于 
      Move inode inactivation to background work contexts so that it no
longer runs in the context that releases the final reference to an
inode. This will allow process work that ends up blocking on
inactivation to continue doing work while the filesytem processes
the inactivation in the background.

A typical demonstration of this is unlinking an inode with lots of
extents. The extents are removed during inactivation, so this blocks
the process that unlinked the inode from the directory structure. By
moving the inactivation to the background process, the userspace
applicaiton can keep working (e.g. unlinking the next inode in the
directory) while the inactivation work on the previous inode is
done by a different CPU.

The implementation of the queue is relatively simple. We use a
per-cpu lockless linked list (llist) to queue inodes for
inactivation without requiring serialisation mechanisms, and a work
item to allow the queue to be processed by a CPU bound worker
thread. We also keep a count of the queue depth so that we can
trigger work after a number of deferred inactivations have been
queued.

The use of a bound workqueue with a single work depth allows the
workqueue to run one work item per CPU. We queue the work item on
the CPU we are currently running on, and so this essentially gives
us affine per-cpu worker threads for the per-cpu queues. THis
maintains the effective CPU affinity that occurs within XFS at the
AG level due to all objects in a directory being local to an AG.
Hence inactivation work tends to run on the same CPU that last
accessed all the objects that inactivation accesses and this
maintains hot CPU caches for unlink workloads.

A depth of 32 inodes was chosen to match the number of inodes in an
inode cluster buffer. This hopefully allows sequential
allocation/unlink behaviours to defering inactivation of all the
inodes in a single cluster buffer at a time, further helping
maintain hot CPU and buffer cache accesses while running
inactivations.

A hard per-cpu queue throttle of 256 inode has been set to avoid
runaway queuing when inodes that take a long to time inactivate are
being processed. For example, when unlinking inodes with large
numbers of extents that can take a lot of processing to free.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
[djwong: tweak comments and tracepoints, convert opflags to state bits]
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>
      ab23a776
    • D
      xfs: detach dquots from inode if we don't need to inactivate it · 62af7d54
      由 Darrick J. Wong 提交于 
      If we don't need to inactivate an inode, we can detach the dquots and
move on to reclamation.  This isn't strictly required here; it's a
preparation patch for deferred inactivation per reviewer request[1] to
move the creation of xfs_inode_needs_inactivation into a separate
change.  Eventually this !need_inactive chunk will turn into the code
path for inodes that skip xfs_inactive and go straight to memory
reclaim.

[1] https://lore.kernel.org/linux-xfs/20210609012838.GW2945738@locust/T/#mca6d958521cb88bbc1bfe1a30767203328d410b5Signed-off-by: NDarrick J. Wong <djwong@kernel.org>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
      62af7d54
  21. 13 7月, 2021 2 次提交
  23. 02 6月, 2021 1 次提交
  25. 08 4月, 2021 12 次提交
  27. 26 3月, 2021 2 次提交
    • D
      xfs: initialise attr fork on inode create · e6a688c3
      由 Dave Chinner 提交于 
      When we allocate a new inode, we often need to add an attribute to
the inode as part of the create. This can happen as a result of
needing to add default ACLs or security labels before the inode is
made visible to userspace.

This is highly inefficient right now. We do the create transaction
to allocate the inode, then we do an "add attr fork" transaction to
modify the just created empty inode to set the inode fork offset to
allow attributes to be stored, then we go and do the attribute
creation.

This means 3 transactions instead of 1 to allocate an inode, and
this greatly increases the load on the CIL commit code, resulting in
excessive contention on the CIL spin locks and performance
degradation:

 18.99%  [kernel]                [k] __pv_queued_spin_lock_slowpath
  3.57%  [kernel]                [k] do_raw_spin_lock
  2.51%  [kernel]                [k] __raw_callee_save___pv_queued_spin_unlock
  2.48%  [kernel]                [k] memcpy
  2.34%  [kernel]                [k] xfs_log_commit_cil

The typical profile resulting from running fsmark on a selinux enabled
filesytem is adds this overhead to the create path:

  - 15.30% xfs_init_security
     - 15.23% security_inode_init_security
	- 13.05% xfs_initxattrs
	   - 12.94% xfs_attr_set
	      - 6.75% xfs_bmap_add_attrfork
		 - 5.51% xfs_trans_commit
		    - 5.48% __xfs_trans_commit
		       - 5.35% xfs_log_commit_cil
			  - 3.86% _raw_spin_lock
			     - do_raw_spin_lock
				  __pv_queued_spin_lock_slowpath
		 - 0.70% xfs_trans_alloc
		      0.52% xfs_trans_reserve
	      - 5.41% xfs_attr_set_args
		 - 5.39% xfs_attr_set_shortform.constprop.0
		    - 4.46% xfs_trans_commit
		       - 4.46% __xfs_trans_commit
			  - 4.33% xfs_log_commit_cil
			     - 2.74% _raw_spin_lock
				- do_raw_spin_lock
				     __pv_queued_spin_lock_slowpath
			       0.60% xfs_inode_item_format
		      0.90% xfs_attr_try_sf_addname
	- 1.99% selinux_inode_init_security
	   - 1.02% security_sid_to_context_force
	      - 1.00% security_sid_to_context_core
		 - 0.92% sidtab_entry_to_string
		    - 0.90% sidtab_sid2str_get
			 0.59% sidtab_sid2str_put.part.0
	   - 0.82% selinux_determine_inode_label
	      - 0.77% security_transition_sid
		   0.70% security_compute_sid.part.0

And fsmark creation rate performance drops by ~25%. The key point to
note here is that half the additional overhead comes from adding the
attribute fork to the newly created inode. That's crazy, considering
we can do this same thing at inode create time with a couple of
lines of code and no extra overhead.

So, if we know we are going to add an attribute immediately after
creating the inode, let's just initialise the attribute fork inside
the create transaction and chop that whole chunk of code out of
the create fast path. This completely removes the performance
drop caused by enabling SELinux, and the profile looks like:

     - 8.99% xfs_init_security
         - 9.00% security_inode_init_security
            - 6.43% xfs_initxattrs
               - 6.37% xfs_attr_set
                  - 5.45% xfs_attr_set_args
                     - 5.42% xfs_attr_set_shortform.constprop.0
                        - 4.51% xfs_trans_commit
                           - 4.54% __xfs_trans_commit
                              - 4.59% xfs_log_commit_cil
                                 - 2.67% _raw_spin_lock
                                    - 3.28% do_raw_spin_lock
                                         3.08% __pv_queued_spin_lock_slowpath
                                   0.66% xfs_inode_item_format
                        - 0.90% xfs_attr_try_sf_addname
                  - 0.60% xfs_trans_alloc
            - 2.35% selinux_inode_init_security
               - 1.25% security_sid_to_context_force
                  - 1.21% security_sid_to_context_core
                     - 1.19% sidtab_entry_to_string
                        - 1.20% sidtab_sid2str_get
                           - 0.86% sidtab_sid2str_put.part.0
                              - 0.62% _raw_spin_lock_irqsave
                                 - 0.77% do_raw_spin_lock
                                      __pv_queued_spin_lock_slowpath
               - 0.84% selinux_determine_inode_label
                  - 0.83% security_transition_sid
                       0.86% security_compute_sid.part.0

Which indicates the XFS overhead of creating the selinux xattr has
been halved. This doesn't fix the CIL lock contention problem, just
means it's not a limiting factor for this workload. Lock contention
in the security subsystems is going to be an issue soon, though...
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
[djwong: fix compilation error when CONFIG_SECURITY=n]
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>
Reviewed-by: NGao Xiang <hsiangkao@redhat.com>
      e6a688c3
    • D
      xfs: prevent metadata files from being inactivated · 383e32b0
      由 Darrick J. Wong 提交于 
      Files containing metadata (quota records, rt bitmap and summary info)
are fully managed by the filesystem, which means that all resource
cleanup must be explicit, not automatic.  This means that they should
never be subjected automatic to post-eof truncation, nor should they be
freed automatically even if the link count drops to zero.

In other words, xfs_inactive() should leave these files alone.  Add the
necessary predicate functions to make this happen.  This adds a second
layer of prevention for the kinds of fs corruption that was fixed by
commit f4c32e87.  If we ever decide to support removing metadata
files, we should make all those metadata updates explicit.

Rearrange the order of #includes to fix compiler errors, since
xfs_mount.h is supposed to be included before xfs_inode.h

Followup-to: f4c32e87 ("xfs: fix realtime bitmap/summary file truncation when growing rt volume")
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
      383e32b0
  29. 24 1月, 2021 1 次提交
  31. 13 12月, 2020 1 次提交
  33. 16 9月, 2020 1 次提交
  35. 07 9月, 2020 1 次提交
    • D
      xfs: xfs_iflock is no longer a completion · 718ecc50
      由 Dave Chinner 提交于 
      With the recent rework of the inode cluster flushing, we no longer
ever wait on the the inode flush "lock". It was never a lock in the
first place, just a completion to allow callers to wait for inode IO
to complete. We now never wait for flush completion as all inode
flushing is non-blocking. Hence we can get rid of all the iflock
infrastructure and instead just set and check a state flag.

Rename the XFS_IFLOCK flag to XFS_IFLUSHING, convert all the
xfs_iflock_nowait() test-and-set operations on that flag, and
replace all the xfs_ifunlock() calls to clear operations.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      718ecc50
  37. 07 7月, 2020 3 次提交
    • D
      xfs: rework xfs_iflush_cluster() dirty inode iteration · 5717ea4d
      由 Dave Chinner 提交于 
      Now that we have all the dirty inodes attached to the cluster
buffer, we don't actually have to do radix tree lookups to find
them. Sure, the radix tree is efficient, but walking a linked list
of just the dirty inodes attached to the buffer is much better.

We are also no longer dependent on having a locked inode passed into
the function to determine where to start the lookup. This means we
can drop it from the function call and treat all inodes the same.

We also make xfs_iflush_cluster skip inodes marked with
XFS_IRECLAIM. This we avoid races with inodes that reclaim is
actively referencing or are being re-initialised by inode lookup. If
they are actually dirty, they'll get written by a future cluster
flush....

We also add a shutdown check after obtaining the flush lock so that
we catch inodes that are dirty in memory and may have inconsistent
state due to the shutdown in progress. We abort these inodes
directly and so they remove themselves directly from the buffer list
and the AIL rather than having to wait for the buffer to be failed
and callbacks run to be processed correctly.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      5717ea4d
    • D
      xfs: xfs_iflush() is no longer necessary · 90c60e16
      由 Dave Chinner 提交于 
      Now we have a cached buffer on inode log items, we don't need
to do buffer lookups when flushing inodes anymore - all we need
to do is lock the buffer and we are ready to go.

This largely gets rid of the need for xfs_iflush(), which is
essentially just a mechanism to look up the buffer and flush the
inode to it. Instead, we can just call xfs_iflush_cluster() with a
few modifications to ensure it also flushes the inode we already
hold locked.

This allows the AIL inode item pushing to be almost entirely
non-blocking in XFS - we won't block unless memory allocation
for the cluster inode lookup blocks or the block device queues are
full.

Writeback during inode reclaim becomes a little more complex because
we now have to lock the buffer ourselves, but otherwise this change
is largely a functional no-op that removes a whole lot of code.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      90c60e16
    • D
      xfs: move helpers that lock and unlock two inodes against userspace IO · e2aaee9c
      由 Darrick J. Wong 提交于 
      Move the double-inode locking helpers to xfs_inode.c since they're not
specific to reflink.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
      e2aaee9c