Commit Graph

130 Commits

Author SHA1 Message Date
Darrick J. Wong 3eeac33116 xfs: allow unlinked symlinks and dirs with zero size
commit 1ec9307fc066dd8a140d5430f8a7576aa9d78cd3 upstream.

For a very very long time, inode inactivation has set the inode size to
zero before unmapping the extents associated with the data fork.
Unfortunately, commit 3c6f46eacd changed the inode verifier to
prohibit zero-length symlinks and directories.  If an inode happens to
get logged in this state and the system crashes before freeing the
inode, log recovery will also fail on the broken inode.

Therefore, allow zero-size symlinks and directories as long as the link
count is zero; nobody will be able to open these files by handle so
there isn't any risk of data exposure.

Fixes: 3c6f46eacd ("xfs: sanity check directory inode di_size")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
Acked-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-10-22 15:46:24 +02:00
Darrick J. Wong 0aca73915d xfs: allow symlinks with short remote targets
commit 38de567906d95c397d87f292b892686b7ec6fbc3 upstream.

An internal user complained about log recovery failing on a symlink
("Bad dinode after recovery") with the following (excerpted) format:

core.magic = 0x494e
core.mode = 0120777
core.version = 3
core.format = 2 (extents)
core.nlinkv2 = 1
core.nextents = 1
core.size = 297
core.nblocks = 1
core.naextents = 0
core.forkoff = 0
core.aformat = 2 (extents)
u3.bmx[0] = [startoff,startblock,blockcount,extentflag]
0:[0,12,1,0]

This is a symbolic link with a 297-byte target stored in a disk block,
which is to say this is a symlink with a remote target.  The forkoff is
0, which is to say that there's 512 - 176 == 336 bytes in the inode core
to store the data fork.

Eventually, testing of generic/388 failed with the same inode corruption
message during inode recovery.  In writing a debugging patch to call
xfs_dinode_verify on dirty inode log items when we're committing
transactions, I observed that xfs/298 can reproduce the problem quite
quickly.

xfs/298 creates a symbolic link, adds some extended attributes, then
deletes them all.  The test failure occurs when the final removexattr
also deletes the attr fork because that does not convert the remote
symlink back into a shortform symlink.  That is how we trip this test.
The only reason why xfs/298 only triggers with the debug patch added is
that it deletes the symlink, so the final iflush shows the inode as
free.

I wrote a quick fstest to emulate the behavior of xfs/298, except that
it leaves the symlinks on the filesystem after inducing the "corrupt"
state.  Kernels going back at least as far as 4.18 have written out
symlink inodes in this manner and prior to 1eb70f54c4 they did not
object to reading them back in.

Because we've been writing out inodes this way for quite some time, the
only way to fix this is to relax the check for symbolic links.
Directories don't have this problem because di_size is bumped to
blocksize during the sf->data conversion.

Fixes: 1eb70f54c4 ("xfs: validate inode fork size against fork format")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
Acked-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-10-22 15:46:24 +02:00
Dave Chinner b28b234276 xfs: inode recovery does not validate the recovered inode
commit 038ca189c0d2c1570b4d922f25b524007c85cf94 upstream.

Discovered when trying to track down a weird recovery corruption
issue that wasn't detected at recovery time.

The specific corruption was a zero extent count field when big
extent counts are in use, and it turns out the dinode verifier
doesn't detect that specific corruption case, either. So fix it too.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
Acked-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-16 19:10:45 +01:00
Jeff Layton a0a415e34b xfs: convert to ctime accessor functions
In later patches, we're going to change how the inode's ctime field is
used. Switch to using accessor functions instead of raw accesses of
inode->i_ctime.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-80-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-07-24 10:30:06 +02:00
Darrick J. Wong 6d200bdc01 xfs: make attr forks permanent
This series fixes a use-after-free bug that syzbot uncovered.  The UAF
 itself is a result of a race condition between getxattr and removexattr
 because callers to getxattr do not necessarily take any sort of locks
 before calling into the filesystem.
 
 Although the race condition itself can be fixed through clever use of a
 memory barrier, further consideration of the use cases of extended
 attributes shows that most files always have at least one attribute, so
 we might as well make them permanent.
 
 v2: Minor tweaks suggested by Dave, and convert some more macros to
 helper functions.
 
 Signed-off-by: Darrick J. Wong <djwong@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEUzaAxoMeQq6m2jMV+H93GTRKtOsFAmLQRsAACgkQ+H93GTRK
 tOseOw/+JdSH2MU2xx+XoE5M/fStzGpw0UsoOqDo8kUPKDt3z12NwuczlL4OAiuw
 XFrN/1IAnxBsTD9YxFYbqoCPNi/VR81ajfWV7JqD2B1Joj0aATsxGDdNUYJnxCdU
 HMlMqP5o77XvArwkxFbgxYi7UGdAeNwXxqUJcJ8FopQo2lb8+SG6XzpLgGKnyrKT
 FRNKXNObplhtzOs/Bv8qYAxJulmmjkktFJXhK2OAUJlIDjFwFY9Wo2T4QuOVe9w+
 NXFOYyu0BqWLpDZQkYKWoCnF0GNsUavS8DP6zZYW3qJ6mX/f1jmtfbOLAkHNhlh8
 uHy/3k3SeQhKztTqM28sPioe6mdj2xocorDCCVBgGXgWxVF6aWeM/PS4tMTWN/Bg
 TWd1egERpeVC0Ymkm0LTCIDNuLqxsknK1G6sxXhwrQ8cw/70Gl08ePwgdyZ6hpD9
 Q61iJQofcI7MJX189a2VSbbHRzFnZIA+uVK4oyhmdEkQVKTHgmzwHVP660oAv9bD
 Y5hqkWEoyKTaaCsOWRAPVXG3k03lq+TNcaGggZgwFx11Gw4oMEx5hMUztoP54xX4
 aEXb1HWcCmMxy8llnFY/82baW98ucwl8FwWF1qhNIPT40mYx9IobDmvkCtNrAoOC
 41U7O8CxxPlt7XKxoRhafQOAhzp0ZzuhCdbaFIUENV7pTAJtq5Q=
 =W3Ad
 -----END PGP SIGNATURE-----

Merge tag 'make-attr-fork-permanent-5.20_2022-07-14' of git://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux into xfs-5.20-mergeB

xfs: make attr forks permanent

This series fixes a use-after-free bug that syzbot uncovered.  The UAF
itself is a result of a race condition between getxattr and removexattr
because callers to getxattr do not necessarily take any sort of locks
before calling into the filesystem.

Although the race condition itself can be fixed through clever use of a
memory barrier, further consideration of the use cases of extended
attributes shows that most files always have at least one attribute, so
we might as well make them permanent.

v2: Minor tweaks suggested by Dave, and convert some more macros to
helper functions.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>

* tag 'make-attr-fork-permanent-5.20_2022-07-14' of git://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux:
  xfs: replace inode fork size macros with functions
  xfs: replace XFS_IFORK_Q with a proper predicate function
  xfs: use XFS_IFORK_Q to determine the presence of an xattr fork
  xfs: make inode attribute forks a permanent part of struct xfs_inode
  xfs: convert XFS_IFORK_PTR to a static inline helper
2022-07-14 09:46:37 -07:00
Dave Chinner 4fcc94d653 xfs: track the iunlink list pointer in the xfs_inode
Having direct access to the i_next_unlinked pointer in unlinked
inodes greatly simplifies the processing of inodes on the unlinked
list. We no longer need to look up the inode buffer just to find
next inode in the list if the xfs_inode is in memory. These
improvements will be realised over upcoming patches as other
dependencies on the inode buffer for unlinked list processing are
removed.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2022-07-14 11:38:54 +10:00
Darrick J. Wong e45d7cb235 xfs: use XFS_IFORK_Q to determine the presence of an xattr fork
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: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-07-09 15:17:21 -07:00
Darrick J. Wong 2ed5b09b3e xfs: make inode attribute forks a permanent part of struct xfs_inode
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: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-07-09 15:17:21 -07:00
Dave Chinner 2d6ca8321c xfs: Pre-calculate per-AG agino geometry
There is a lot of overhead in functions like xfs_verify_agino() that
repeatedly calculate the geometry limits of an AG. These can be
pre-calculated as they are static and the verification context has
a per-ag context it can quickly reference.

In the case of xfs_verify_agino(), we now always have a perag
context handy, so we can store the minimum and maximum agino values
in the AG in the perag. This means we don't have to calculate
it on every call and it can be inlined in callers if we move it
to xfs_ag.h.

xfs_verify_agino_or_null() gets the same perag treatment.

xfs_agino_range() is moved to xfs_ag.c as it's not really a type
function, and it's use is largely restricted as the first and last
aginos can be grabbed straight from the perag in most cases.

Note that we leave the original xfs_verify_agino in place in
xfs_types.c as a static function as other callers in that file do
not have per-ag contexts so still need to go the long way. It's been
renamed to xfs_verify_agno_agino() to indicate it takes both an agno
and an agino to differentiate it from new function.

$ size --totals fs/xfs/built-in.a
	   text    data     bss     dec     hex filename
before	1482185	 329588	    572	1812345	 1ba779	(TOTALS)
after	1481937	 329588	    572	1812097	 1ba681	(TOTALS)

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2022-07-07 19:13:10 +10:00
Dave Chinner 1eb70f54c4 xfs: validate inode fork size against fork format
xfs_repair catches fork size/format mismatches, but the in-kernel
verifier doesn't, leading to null pointer failures when attempting
to perform operations on the fork. This can occur in the
xfs_dir_is_empty() where the in-memory fork format does not match
the size and so the fork data pointer is accessed incorrectly.

Note: this causes new failures in xfs/348 which is testing mode vs
ftype mismatches. We now detect a regular file that has been changed
to a directory or symlink mode as being corrupt because the data
fork is for a symlink or directory should be in local form when
there are only 3 bytes of data in the data fork. Hence the inode
verify for the regular file now fires w/ -EFSCORRUPTED because
the inode fork format does not match the format the corrupted mode
says it should be in.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-05-04 12:13:53 +10:00
Chandan Babu R 83a21c1844 xfs: Directory's data fork extent counter can never overflow
The maximum file size that can be represented by the data fork extent counter
in the worst case occurs when all extents are 1 block in length and each block
is 1KB in size.

With XFS_MAX_EXTCNT_DATA_FORK_SMALL representing maximum extent count and with
1KB sized blocks, a file can reach upto,
(2^31) * 1KB = 2TB

This is much larger than the theoretical maximum size of a directory
i.e. XFS_DIR2_SPACE_SIZE * 3 = ~96GB.

Since a directory's inode can never overflow its data fork extent counter,
this commit removes all the overflow checks associated with
it. xfs_dinode_verify() now performs a rough check to verify if a diretory's
data fork is larger than 96GB.

Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandan.babu@oracle.com>
2022-04-13 07:02:07 +00:00
Chandan Babu R 52a4a14842 xfs: Introduce per-inode 64-bit extent counters
This commit introduces new fields in the on-disk inode format to support
64-bit data fork extent counters and 32-bit attribute fork extent
counters. The new fields will be used only when an inode has
XFS_DIFLAG2_NREXT64 flag set. Otherwise we continue to use the regular 32-bit
data fork extent counters and 16-bit attribute fork extent counters.

Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Chandan Babu R <chandan.babu@oracle.com>
Suggested-by: Dave Chinner <dchinner@redhat.com>
2022-04-11 04:11:20 +00:00
Chandan Babu R df9ad5cc7a xfs: Introduce macros to represent new maximum extent counts for data/attr forks
This commit defines new macros to represent maximum extent counts allowed by
filesystems which have support for large per-inode extent counters.

Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Chandan Babu R <chandan.babu@oracle.com>
2022-04-11 04:11:19 +00:00
Chandan Babu R dd95a6ce31 xfs: Introduce xfs_dfork_nextents() helper
This commit replaces the macro XFS_DFORK_NEXTENTS() with the helper function
xfs_dfork_nextents(). As of this commit, xfs_dfork_nextents() returns the same
value as XFS_DFORK_NEXTENTS(). A future commit which extends inode's extent
counter fields will add more logic to this helper.

This commit also replaces direct accesses to xfs_dinode->di_[a]nextents
with calls to xfs_dfork_nextents().

No functional changes have been made.

Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Chandan Babu R <chandan.babu@oracle.com>
2022-04-11 04:11:18 +00:00
Chandan Babu R bb1d50494c xfs: Use xfs_extnum_t instead of basic data types
xfs_extnum_t is the type to use to declare variables which have values
obtained from xfs_dinode->di_[a]nextents. This commit replaces basic
types (e.g. uint32_t) with xfs_extnum_t for such variables.

Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Chandan Babu R <chandan.babu@oracle.com>
2022-04-11 04:11:17 +00:00
Chandan Babu R 9feb8f1966 xfs: Introduce xfs_iext_max_nextents() helper
xfs_iext_max_nextents() returns the maximum number of extents possible for one
of data, cow or attribute fork. This helper will be extended further in a
future commit when maximum extent counts associated with data/attribute forks
are increased.

Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Chandan Babu R <chandan.babu@oracle.com>
2022-04-11 04:11:17 +00:00
Chandan Babu R 95f0b95e2b xfs: Define max extent length based on on-disk format definition
The maximum extent length depends on maximum block count that can be stored in
a BMBT record. Hence this commit defines MAXEXTLEN based on
BMBT_BLOCKCOUNT_BITLEN.

While at it, the commit also renames MAXEXTLEN to XFS_MAX_BMBT_EXTLEN.

Suggested-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Chandan Babu R <chandan.babu@oracle.com>
2022-04-11 04:11:17 +00:00
Christoph Hellwig de38db7239 xfs: remove the xfs_dinode_t typedef
Remove the few leftover instances of the xfs_dinode_t typedef.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-10-14 09:19:33 -07:00
Dave Chinner 9343ee7690 xfs: convert bp->b_bn references to xfs_buf_daddr()
Stop directly referencing b_bn in code outside the buffer cache, as
b_bn is supposed to be used only as an internal cache index.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-08-19 10:07:15 -07:00
Dave Chinner 04fcad80cd xfs: introduce xfs_buf_daddr()
Introduce a helper function xfs_buf_daddr() to extract the disk
address of the buffer from the struct xfs_buf. This will replace
direct accesses to bp->b_bn and bp->b_maps[0].bm_bn, as well as
the XFS_BUF_ADDR() macro.

This patch introduces the helper function and replaces all uses of
XFS_BUF_ADDR() as this is just a simple sed replacement.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-08-19 10:07:14 -07:00
Dave Chinner cf28e17c91 xfs: kill xfs_sb_version_has_v3inode()
All callers to xfs_dinode_good_version() and XFS_DINODE_SIZE() in
both the kernel and userspace have a xfs_mount structure available
which means they can use mount features checks instead looking
directly are the superblock.

Convert these functions to take a mount and use a xfs_has_v3inodes()
check and move it out of the libxfs/xfs_format.h file as it really
doesn't have anything to do with the definition of the on-disk
format.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-08-19 10:07:14 -07:00
Dave Chinner ebd9027d08 xfs: convert xfs_sb_version_has checks to use mount features
This is a conversion of the remaining xfs_sb_version_has..(sbp)
checks to use xfs_has_..(mp) feature checks.

This was largely done with a vim replacement macro that did:

:0,$s/xfs_sb_version_has\(.*\)&\(.*\)->m_sb/xfs_has_\1\2/g<CR>

A couple of other variants were also used, and the rest touched up
by hand.

$ size -t fs/xfs/built-in.a
	   text    data     bss     dec     hex filename
before	1127533  311352     484 1439369  15f689 (TOTALS)
after	1125360  311352     484 1437196  15ee0c (TOTALS)

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-08-19 10:07:14 -07:00
Dave Chinner 38c26bfd90 xfs: replace xfs_sb_version checks with feature flag checks
Convert the xfs_sb_version_hasfoo() to checks against
mp->m_features. Checks of the superblock itself during disk
operations (e.g. in the read/write verifiers and the to/from disk
formatters) are not converted - they operate purely on the
superblock state. Everything else should use the mount features.

Large parts of this conversion were done with sed with commands like
this:

for f in `git grep -l xfs_sb_version_has fs/xfs/*.c`; do
	sed -i -e 's/xfs_sb_version_has\(.*\)(&\(.*\)->m_sb)/xfs_has_\1(\2)/' $f
done

With manual cleanups for things like "xfs_has_extflgbit" and other
little inconsistencies in naming.

The result is ia lot less typing to check features and an XFS binary
size reduced by a bit over 3kB:

$ size -t fs/xfs/built-in.a
	text	   data	    bss	    dec	    hex	filenam
before	1130866  311352     484 1442702  16038e (TOTALS)
after	1127727  311352     484 1439563  15f74b (TOTALS)

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-08-19 10:07:12 -07:00
Darrick J. Wong 83193e5ebb xfs: correct the narrative around misaligned rtinherit/extszinherit dirs
While auditing the realtime growfs code, I realized that the GROWFSRT
ioctl (and by extension xfs_growfs) has always allowed sysadmins to
change the realtime extent size when adding a realtime section to the
filesystem.  Since we also have always allowed sysadmins to set
RTINHERIT and EXTSZINHERIT on directories even if there is no realtime
device, this invalidates the premise laid out in the comments added in
commit 603f000b15.

In other words, this is not a case of inadequate metadata validation.
This is a case of nearly forgotten (and apparently untested) but
supported functionality.  Update the comments to reflect what we've
learned, and remove the log message about correcting the misalignment.

Fixes: 603f000b15 ("xfs: validate extsz hints against rt extent size when rtinherit is set")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2021-07-15 09:58:42 -07:00
Darrick J. Wong a7bcb147fe xfs: clean up open-coded fs block unit conversions
Replace some open-coded fs block unit conversions with the standard
conversion macro.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
2021-06-01 12:53:59 -07:00
Darrick J. Wong 603f000b15 xfs: validate extsz hints against rt extent size when rtinherit is set
The RTINHERIT bit can be set on a directory so that newly created
regular files will have the REALTIME bit set to store their data on the
realtime volume.  If an extent size hint (and EXTSZINHERIT) are set on
the directory, the hint will also be copied into the new file.

As pointed out in previous patches, for realtime files we require the
extent size hint be an integer multiple of the realtime extent, but we
don't perform the same validation on a directory with both RTINHERIT and
EXTSZINHERIT set, even though the only use-case of that combination is
to propagate extent size hints into new realtime files.  This leads to
inode corruption errors when the bad values are propagated.

Because there may be existing filesystems with such a configuration, we
cannot simply amend the inode verifier to trip on these directories and
call it a day because that will cause previously "working" filesystems
to start throwing errors abruptly.  Note that it's valid to have
directories with rtinherit set even if there is no realtime volume, in
which case the problem does not manifest because rtinherit is ignored if
there's no realtime device; and it's possible that someone set the flag,
crashed, repaired the filesystem (which clears the hint on the realtime
file) and continued.

Therefore, mitigate this issue in several ways: First, if we try to
write out an inode with both rtinherit/extszinherit set and an unaligned
extent size hint, turn off the hint to correct the error.  Second, if
someone tries to misconfigure a directory via the fssetxattr ioctl, fail
the ioctl.  Third, reverify both extent size hint values when we
propagate heritable inode attributes from parent to child, to prevent
misconfigurations from spreading.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2021-05-24 18:01:04 -07:00
Darrick J. Wong 6b69e48589 xfs: standardize extent size hint validation
While chasing a bug involving invalid extent size hints being propagated
into newly created realtime files, I noticed that the xfs_ioctl_setattr
checks for the extent size hints weren't the same as the ones now
encoded in libxfs and used for validation in repair and mkfs.

Because the checks in libxfs are more stringent than the ones in the
ioctl, it's possible for a live system to set inode flags that
immediately result in corruption warnings.  Specifically, it's possible
to set an extent size hint on an rtinherit directory without checking if
the hint is aligned to the realtime extent size, which makes no sense
since that combination is used only to seed new realtime files.

Replace the open-coded and inadequate checks with the libxfs verifier
versions and update the code comments a bit.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2021-05-24 18:01:04 -07:00
Christoph Hellwig e98d5e882b xfs: move the di_crtime field to struct xfs_inode
Move the crtime field from struct xfs_icdinode into stuct xfs_inode and
remove the now entirely unused struct xfs_icdinode.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:05 -07:00
Christoph Hellwig 3e09ab8fdc xfs: move the di_flags2 field to struct xfs_inode
In preparation of removing the historic icinode struct, move the flags2
field into the containing xfs_inode structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:05 -07:00
Christoph Hellwig db07349da2 xfs: move the di_flags field to struct xfs_inode
In preparation of removing the historic icinode struct, move the flags
field into the containing xfs_inode structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:05 -07:00
Christoph Hellwig 7821ea302d xfs: move the di_forkoff field to struct xfs_inode
In preparation of removing the historic icinode struct, move the
forkoff field into the containing xfs_inode structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:05 -07:00
Christoph Hellwig ee7b83fd36 xfs: use a union for i_cowextsize and i_flushiter
The i_cowextsize field is only used for v3 inodes, and the i_flushiter
field is only used for v1/v2 inodes.  Use a union to pack the inode a
littler better after adding a few missing guards around their usage.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:05 -07:00
Christoph Hellwig 965e0a1ad2 xfs: move the di_flushiter field to struct xfs_inode
In preparation of removing the historic icinode struct, move the
flushiter field into the containing xfs_inode structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:04 -07:00
Christoph Hellwig b33ce57d3e xfs: move the di_cowextsize field to struct xfs_inode
In preparation of removing the historic icinode struct, move the
cowextsize field into the containing xfs_inode structure.  Also
switch to use the xfs_extlen_t instead of a uint32_t.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:04 -07:00
Christoph Hellwig 031474c28a xfs: move the di_extsize field to struct xfs_inode
In preparation of removing the historic icinode struct, move the extsize
field into the containing xfs_inode structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:04 -07:00
Christoph Hellwig 6e73a545f9 xfs: move the di_nblocks field to struct xfs_inode
In preparation of removing the historic icinode struct, move the nblocks
field into the containing xfs_inode structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:03 -07:00
Christoph Hellwig 13d2c10b05 xfs: move the di_size field to struct xfs_inode
In preparation of removing the historic icinode struct, move the on-disk
size field into the containing xfs_inode structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:03 -07:00
Christoph Hellwig ceaf603c70 xfs: move the di_projid field to struct xfs_inode
In preparation of removing the historic icinode struct, move the projid
field into the containing xfs_inode structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:03 -07:00
Christoph Hellwig 9b3beb028f xfs: remove the di_dmevmask and di_dmstate fields from struct xfs_icdinode
The legacy DMAPI fields were never set by upstream Linux XFS, and have no
way to be read using the kernel APIs.  So instead of bloating the in-core
inode for them just copy them from the on-disk inode into the log when
logging the inode.  The only caveat is that we need to make sure to zero
the fields for newly read or deleted inodes, which is solved using a new
flag in the inode.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:03 -07:00
Christoph Hellwig af9dcddef6 xfs: split xfs_imap_to_bp
Split looking up the dinode from xfs_imap_to_bp, which can be
significantly simplified as a result.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:02 -07:00
Eric Sandeen 207ddc0ef4 xfs: don't catch dax+reflink inodes as corruption in verifier
We don't yet support dax on reflinked files, but that is in the works.

Further, having the flag set does not automatically mean that the inode
is actually "in the CPU direct access state," which depends on several
other conditions in addition to the flag being set.

As such, we should not catch this as corruption in the verifier - simply
not actually enabling S_DAX on reflinked files is enough for now.

Fixes: 4f435ebe7d ("xfs: don't mix reflink and DAX mode for now")
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
[darrick: fix the scrubber too]
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-12-09 09:49:38 -08:00
Darrick J. Wong f93e5436f0 xfs: widen ondisk inode timestamps to deal with y2038+
Redesign the ondisk inode timestamps to be a simple unsigned 64-bit
counter of nanoseconds since 14 Dec 1901 (i.e. the minimum time in the
32-bit unix time epoch).  This enables us to handle dates up to 2486,
which solves the y2038 problem.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Gao Xiang <hsiangkao@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2020-09-15 20:52:41 -07:00
Darrick J. Wong 5a0bb066f6 xfs: redefine xfs_timestamp_t
Redefine xfs_timestamp_t as a __be64 typedef in preparation for the
bigtime functionality.  Preserve the legacy structure format so that we
can let the compiler take care of masking and shifting.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Gao Xiang <hsiangkao@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2020-09-15 20:52:41 -07:00
Darrick J. Wong 88947ea0ba xfs: move xfs_log_dinode_to_disk to the log recovery code
Move this function to xfs_inode_item_recover.c since there's only one
caller of it.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Gao Xiang <hsiangkao@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2020-09-15 20:52:40 -07:00
Dave Chinner e2705b0304 xfs: remove xfs_inobp_check()
This debug code is called on every xfs_iflush() call, which then
checks every inode in the buffer for non-zero unlinked list field.
Hence it checks every inode in the cluster buffer every time a
single inode on that cluster it flushed. This is resulting in:

-   38.91%     5.33%  [kernel]  [k] xfs_iflush
   - 17.70% xfs_iflush
      - 9.93% xfs_inobp_check
           4.36% xfs_buf_offset

10% of the CPU time spent flushing inodes is repeatedly checking
unlinked fields in the buffer. We don't need to do this.

The other place we call xfs_inobp_check() is
xfs_iunlink_update_dinode(), and this is after we've done this
assert for the agino we are about to write into that inode:

	ASSERT(xfs_verify_agino_or_null(mp, agno, next_agino));

which means we've already checked that the agino we are about to
write is not 0 on debug kernels. The inode buffer verifiers do
everything else we need, so let's just remove this debug code.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-07-07 07:15:09 -07:00
Dave Chinner 298f7bec50 xfs: pin inode backing buffer to the inode log item
When we dirty an inode, we are going to have to write it disk at
some point in the near future. This requires the inode cluster
backing buffer to be present in memory. Unfortunately, under severe
memory pressure we can reclaim the inode backing buffer while the
inode is dirty in memory, resulting in stalling the AIL pushing
because it has to do a read-modify-write cycle on the cluster
buffer.

When we have no memory available, the read of the cluster buffer
blocks the AIL pushing process, and this causes all sorts of issues
for memory reclaim as it requires inode writeback to make forwards
progress. Allocating a cluster buffer causes more memory pressure,
and results in more cluster buffers to be reclaimed, resulting in
more RMW cycles to be done in the AIL context and everything then
backs up on AIL progress. Only the synchronous inode cluster
writeback in the the inode reclaim code provides some level of
forwards progress guarantees that prevent OOM-killer rampages in
this situation.

Fix this by pinning the inode backing buffer to the inode log item
when the inode is first dirtied (i.e. in xfs_trans_log_inode()).
This may mean the first modification of an inode that has been held
in cache for a long time may block on a cluster buffer read, but
we can do that in transaction context and block safely until the
buffer has been allocated and read.

Once we have the cluster buffer, the inode log item takes a
reference to it, pinning it in memory, and attaches it to the log
item for future reference. This means we can always grab the cluster
buffer from the inode log item when we need it.

When the inode is finally cleaned and removed from the AIL, we can
drop the reference the inode log item holds on the cluster buffer.
Once all inodes on the cluster buffer are clean, the cluster buffer
will be unpinned and it will be available for memory reclaim to
reclaim again.

This avoids the issues with needing to do RMW cycles in the AIL
pushing context, and hence allows complete non-blocking inode
flushing to be performed by the AIL pushing context.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-07-07 07:15:07 -07:00
Keyur Patel 06734e3c95 xfs: Couple of typo fixes in comments
./xfs/libxfs/xfs_inode_buf.c:56: unnecssary ==> unnecessary
./xfs/libxfs/xfs_inode_buf.c:59: behavour ==> behaviour
./xfs/libxfs/xfs_inode_buf.c:206: unitialized ==> uninitialized

Signed-off-by: Keyur Patel <iamkeyur96@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-07-06 10:46:56 -07:00
Christoph Hellwig ef8385128d xfs: cleanup xfs_idestroy_fork
Move freeing the dynamically allocated attr and COW fork, as well
as zeroing the pointers where actually needed into the callers, and
just pass the xfs_ifork structure to xfs_idestroy_fork.  Also simplify
the kmem_free calls by not checking for NULL first.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-05-19 09:40:59 -07:00
Christoph Hellwig f7e67b20ec xfs: move the fork format fields into struct xfs_ifork
Both the data and attr fork have a format that is stored in the legacy
idinode.  Move it into the xfs_ifork structure instead, where it uses
up padding.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-05-19 09:40:58 -07:00
Christoph Hellwig daf83964a3 xfs: move the per-fork nextents fields into struct xfs_ifork
There are there are three extents counters per inode, one for each of
the forks.  Two are in the legacy icdinode and one is directly in
struct xfs_inode.  Switch to a single counter in the xfs_ifork structure
where it uses up padding at the end of the structure.  This simplifies
various bits of code that just wants the number of extents counter and
can now directly dereference it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-05-19 09:40:58 -07:00