Commit Graph

41956 Commits

Author SHA1 Message Date
Brian Foster
502a4e72b8 xfs: add fs geometry bit for sparse inode chunks
Define an fs geometry bit for sparse inode chunks such that the
characteristic of the fs can be identified by userspace.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-05-29 08:58:32 +10:00
Brian Foster
e5376fc15a xfs: sparse inode chunks feature helpers and mount requirements
The sparse inode chunks feature uses the helper function to enable the
allocation of sparse inode chunks. The incompatible feature bit is set
on disk at mkfs time to prevent mount from unsupported kernels.

Also, enforce the inode alignment requirements required for sparse inode
chunks at mount time. When enabled, full inode chunks (and all inode
record) alignment is increased from cluster size to inode chunk size.
Sparse inode alignment must match the cluster size of the fs. Both
superblock alignment fields are set as such by mkfs when sparse inode
support is enabled.

Finally, warn that sparse inode chunks is an experimental feature until
further notice.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-05-29 08:57:27 +10:00
Brian Foster
066a18845f xfs: use sparse chunk alignment for min. inode allocation requirement
xfs_ialloc_ag_select() iterates through the allocation groups looking
for free inodes or free space to determine whether to allow an inode
allocation to proceed. If no free inodes are available, it assumes that
an AG must have an extent longer than mp->m_ialloc_blks.

Sparse inode chunk support currently allows for allocations smaller than
the traditional inode chunk size specified in m_ialloc_blks. The current
minimum sparse allocation is set in the superblock sb_spino_align field
at mkfs time. Create a new m_ialloc_min_blks field in xfs_mount and use
this to represent the minimum supported allocation size for inode
chunks. Initialize m_ialloc_min_blks at mount time based on whether
sparse inodes are supported.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-05-29 08:55:20 +10:00
Brian Foster
fb4f2b4e5a xfs: add sparse inode chunk alignment superblock field
Add sb_spino_align to the superblock to specify sparse inode chunk
alignment. This also currently represents the minimum allowable sparse
chunk allocation size.

Signed-off-by: Brian Foster <bfoster@redhat.com>
2015-05-29 08:54:03 +10:00
Brian Foster
bfe46d4eb9 xfs: support min/max agbno args in block allocator
The block allocator supports various arguments to tweak block allocation
behavior and set allocation requirements. The sparse inode chunk feature
introduces a new requirement not supported by the current arguments.
Sparse inode allocations must convert or merge into an inode record that
describes a fixed length chunk (64 inodes x inodesize). Full inode chunk
allocations by definition always result in valid inode records. Sparse
chunk allocations are smaller and the associated records can refer to
blocks not owned by the inode chunk. This model can result in invalid
inode records in certain cases.

For example, if a sparse allocation occurs near the start of an AG, the
aligned inode record for that chunk might refer to agbno 0. If an
allocation occurs towards the end of the AG and the AG size is not
aligned, the inode record could refer to blocks beyond the end of the
AG. While neither of these scenarios directly result in corruption, they
both insert invalid inode records and at minimum cause repair to
complain, are unlikely to merge into full chunks over time and set land
mines for other areas of code.

To guarantee sparse inode chunk allocation creates valid inode records,
support the ability to specify an agbno range limit for
XFS_ALLOCTYPE_NEAR_BNO block allocations. The min/max agbno's are
specified in the allocation arguments and limit the block allocation
algorithms to that range. The starting 'agbno' hint is clamped to the
range if the specified agbno is out of range. If no sufficient extent is
available within the range, the allocation fails. For backwards
compatibility, the min/max fields can be initialized to 0 to disable
range limiting (e.g., equivalent to min=0,max=agsize).

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-05-29 08:53:00 +10:00
Brian Foster
999633d304 xfs: update free inode record logic to support sparse inode records
xfs_difree_inobt() uses logic in a couple places that assume inobt
records refer to fully allocated chunks. Specifically, the use of
mp->m_ialloc_inos can cause problems for inode chunks that are sparsely
allocated. Sparse inode chunks can, by definition, define a smaller
number of inodes than a full inode chunk.

Fix the logic that determines whether an inode record should be removed
from the inobt to use the ir_free mask rather than ir_freecount. Fix the
agi counters modification to use ir_freecount to add the actual number
of inodes freed rather than assuming a full inode chunk.

Also make sure that we preserve the behavior to not remove inode chunks
if the block size is large enough for multiple inode chunks (e.g.,
bsize=64k, isize=512). This behavior was previously implicit in that in
such configurations, ir.freecount of a single record never matches
m_ialloc_inos. Hence, add some comments as well.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-05-29 08:51:37 +10:00
Brian Foster
d4cc540b08 xfs: create individual inode alloc. helper
Inode allocation from sparse inode records must filter the ir_free mask
against ir_holemask.  In preparation for this requirement, create a
helper to allocate an individual inode from an inode record.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-05-29 08:50:21 +10:00
Yunlei He
498c5e9fcd f2fs: add default mount options to remount
I use f2fs filesystem with /data partition on my Android phone
by the default mount options. When I remount /data in order to
adding discard option to run some benchmarks, I find the default
options such as background_gc, user_xattr and acl turned off.

So I introduce a function named default_options in super.c. It do
some default setting, and both mount and remount operations will
call this function to complete default setting.

Signed-off-by: Yunlei He <heyunlei@huawei.com>
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:58 -07:00
Jaegeuk Kim
d690358b2b f2fs crypto: remove checking key context during lookup
No matter what the key is valid or not, readdir shows the dir entries correctly.
So, lookup should not failed.
But, we expect further accesses should be denied from open, rename, link, and so
on.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:57 -07:00
Jaegeuk Kim
edf3fb8e9e f2fs crypto: fix missing key when reading a page
1. mount $mnt
2. cp data $mnt/
3. umount $mnt
4. log out
5. log in
6. cat $mnt/data

-> panic, due to no i_crypt_info.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:56 -07:00
Jaegeuk Kim
cbaf042a3c f2fs crypto: add symlink encryption
This patch implements encryption support for symlink.

Signed-off-by: Uday Savagaonkar <savagaon@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:55 -07:00
Jaegeuk Kim
e7d5545285 f2fs crypto: add filename encryption for roll-forward recovery
This patch adds a bit flag to indicate whether or not i_name in the inode
is encrypted.

If this name is encrypted, we can't do recover_dentry during roll-forward.
So, f2fs_sync_file() needs to do checkpoint, if this will be needed in future.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:55 -07:00
Jaegeuk Kim
6e22c691ba f2fs crypto: add filename encryption for f2fs_lookup
This patch implements filename encryption support for f2fs_lookup.

Note that, f2fs_find_entry should be outside of f2fs_(un)lock_op().

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:54 -07:00
Jaegeuk Kim
d8c6822a05 f2fs crypto: add filename encryption for f2fs_readdir
This patch implements filename encryption support for f2fs_readdir.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:53 -07:00
Jaegeuk Kim
9ea97163c6 f2fs crypto: add filename encryption for f2fs_add_link
This patch adds filename encryption support for f2fs_add_link.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:52 -07:00
Jaegeuk Kim
4375a33664 f2fs crypto: add encryption support in read/write paths
This patch adds encryption support in read and write paths.

Note that, in f2fs, we need to consider cleaning operation.
In cleaning procedure, we must avoid encrypting and decrypting written blocks.
So, this patch implements move_encrypted_block().

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:52 -07:00
Jaegeuk Kim
fcc85a4d86 f2fs crypto: activate encryption support for fs APIs
This patch activates the following APIs for encryption support.

The rules quoted by ext4 are:
 - An unencrypted directory may contain encrypted or unencrypted files
   or directories.
 - All files or directories in a directory must be protected using the
   same key as their containing directory.
 - Encrypted inode for regular file should not have inline_data.
 - Encrypted symlink and directory may have inline_data and inline_dentry.

This patch activates the following APIs.
1. f2fs_link              : validate context
2. f2fs_lookup            :      ''
3. f2fs_rename            :      ''
4. f2fs_create/f2fs_mkdir : inherit its dir's context
5. f2fs_direct_IO         : do buffered io for regular files
6. f2fs_open              : check encryption info
7. f2fs_file_mmap         :      ''
8. f2fs_setattr           :      ''
9. f2fs_file_write_iter   :      ''           (Called by sys_io_submit)
10. f2fs_fallocate        : do not support fcollapse
11. f2fs_evict_inode      : free_encryption_info

Signed-off-by: Michael Halcrow <mhalcrow@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:51 -07:00
Jaegeuk Kim
6b3bd08f93 f2fs crypto: filename encryption facilities
This patch adds filename encryption infra.
Most of codes are copied from ext4 part, but changed to adjust f2fs
directory structure.

Signed-off-by: Uday Savagaonkar <savagaon@google.com>
Signed-off-by: Ildar Muslukhov <ildarm@google.com>
Signed-off-by: Michael Halcrow <mhalcrow@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:50 -07:00
Jaegeuk Kim
0adda907f2 f2fs crypto: add encryption key management facilities
This patch copies from encrypt_key.c in ext4, and modifies for f2fs.

Use GFP_NOFS, since _f2fs_get_encryption_info is called under f2fs_lock_op.

Signed-off-by: Michael Halcrow <mhalcrow@google.com>
Signed-off-by: Ildar Muslukhov <muslukhovi@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:49 -07:00
Jaegeuk Kim
57e5055b0a f2fs crypto: add f2fs encryption facilities
Most of parts were copied from ext4, except:

 - add f2fs_restore_and_release_control_page which returns control page and
   restore control page
 - remove ext4_encrypted_zeroout()
 - remove sbi->s_file_encryption_mode & sbi->s_dir_encryption_mode
 - add f2fs_end_io_crypto_work for mpage_end_io

Signed-off-by: Michael Halcrow <mhalcrow@google.com>
Signed-off-by: Ildar Muslukhov <ildarm@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:49 -07:00
Jaegeuk Kim
f424f664f0 f2fs crypto: add encryption policy and password salt support
This patch adds encryption policy and password salt support through ioctl
implementation.

It adds three ioctls:
 F2FS_IOC_SET_ENCRYPTION_POLICY,
 F2FS_IOC_GET_ENCRYPTION_POLICY,
 F2FS_IOC_GET_ENCRYPTION_PWSALT, which use xattr operations.

Note that, these definition and codes are taken from ext4 crypto support.
For f2fs, xattr operations and on-disk flags for superblock and inode were
changed.

Signed-off-by: Michael Halcrow <mhalcrow@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Ildar Muslukhov <muslukhovi@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:48 -07:00
Jaegeuk Kim
b93531dd7b f2fs crypto: add encryption xattr support
This patch add some definition for enrcyption xattr.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:47 -07:00
Jaegeuk Kim
d33793fb89 f2fs crypto: add f2fs encryption Kconfig
This patch adds f2fs encryption config.

This patch integrates:

"ext4 crypto: require CONFIG_CRYPTO_CTR if ext4 encryption is enabled

On arm64 this is apparently needed for CTS mode to function correctly.
Otherwise attempts to use CTS return ENOENT."

Signed-off-by: Michael Halcrow <mhalcrow@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:46 -07:00
Jaegeuk Kim
cde4de1205 f2fs crypto: declare some definitions for f2fs encryption feature
This definitions will be used by inode and superblock for encyption.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:45 -07:00
Jaegeuk Kim
7f63eb77af f2fs: report unwritten area in f2fs_fiemap
This patch slightly changes f2fs_fiemap function to report unwritten area.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:45 -07:00
Jaegeuk Kim
3589a9190b f2fs: avoid value overflow in showing current status
This patch fixes overflow when do cat /sys/kernel/debug/f2fs/status.
If a section is relatively large, dist value can be overflowed.

Reported-by: Yossi Goldfill <ygoldfill@radianmemory.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:44 -07:00
Chao Yu
75cd4e098d f2fs: support FALLOC_FL_ZERO_RANGE
Now, FALLOC_FL_ZERO_RANGE flag in ->fallocate is supported in ext4/xfs.

In commit, the semantics of this flag is descripted as following:"
1) Make sure that both offset and len are block size aligned.
2) Update the i_size of inode by len bytes.
3) Compute the file's logical block number against offset. If the computed
   block number is not the starting block of the extent, split the extent
   such that the block number is the starting block of the extent.
4) Shift all the extents which are lying between
   [offset, last allocated extent] towards right by len bytes. This step
   will make a hole of len bytes at offset."

This patch implements fallocate's FALLOC_FL_ZERO_RANGE for f2fs.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:43 -07:00
Chao Yu
b4ace33703 f2fs: support FALLOC_FL_COLLAPSE_RANGE
Now, FALLOC_FL_COLLAPSE_RANGE flag in ->fallocate is supported in ext4/xfs.

In commit, the semantics of this flag is descripted as following:"
1) It collapses the range lying between offset and length by removing any
   data blocks which are present in this range and than updates all the
   logical offsets of extents beyond "offset + len" to nullify the hole
   created by removing blocks. In short, it does not leave a hole.
2) It should be used exclusively. No other fallocate flag in combination.
3) Offset and length supplied to fallocate should be fs block size aligned
   in case of xfs and ext4.
4) Collaspe range does not work beyond i_size."

This patch implements fallocate's FALLOC_FL_COLLAPSE_RANGE for f2fs.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:42 -07:00
Chao Yu
19f106bc03 f2fs: introduce f2fs_replace_block() for reuse
Introduce a generic function replace_block base on recover_data_page,
and export it. So with it we can operate file's meta data which is in
CP/SSA area when we invoke fallocate with FALLOC_FL_COLLAPSE_RANGE
flag.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:42 -07:00
Chao Yu
d5b692b786 f2fs: do not re-lookup nat cache with same nid
In set_node_addr, we try to lookup cached nat entry of inode and then
set flag in it.

But previously in this function, we have already grabbed nat entry with
current node id, if the node id is the same as the one of inode, we
do not need to lookup it in cache again.

So this patch adds condition judgment for reducing unneeded lookup.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:41 -07:00
Chao Yu
402f721d2f f2fs: remove unneeded f2fs_make_empty declaration
Remove f2fs_make_empty() declaration, since the main body of this function
is move into do_make_empty_dir() and the function is obsolete now.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:40 -07:00
Jaegeuk Kim
836b5a6356 f2fs: issue discard with finally produced len and minlen
This patch determines to issue discard commands by comparing given minlen and
the length of produced final candidates.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:39 -07:00
Jaegeuk Kim
a66cdd9855 f2fs: introduce discard_map for f2fs_trim_fs
This patch adds a bitmap for discard issues from f2fs_trim_fs.
There-in rule is to issue discard commands only for invalidated blocks
after mount.
Once mount is done, f2fs_trim_fs trims out whole invalid area.
After ehn, it will not issue and discrads redundantly.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:39 -07:00
Jaegeuk Kim
d6c67a4fee f2fs: revmove spin_lock for write_orphan_inodes
This patch removes spin_lock, since this is covered by f2fs_lock_op already.
And, we should avoid to use page operations inside spin_lock.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:38 -07:00
Jaegeuk Kim
43f3eae1d3 f2fs: split find_data_page according to specific purposes
This patch splits find_data_page as follows.

1. f2fs_gc
 - use get_read_data_page() with read only

2. find_in_level
 - use find_data_page without locked page

3. truncate_partial_page
 - In the case cache_only mode, just drop cached page.
 - Ohterwise, use get_lock_data_page() and guarantee to truncate

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:37 -07:00
Jaegeuk Kim
2fb2c95496 f2fs: fix counting the number of inline_data inodes
This patch fixes to count the missing symlink case.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:36 -07:00
Jaegeuk Kim
2dcf51ab2f f2fs: add need_dentry_mark
This patch introduces need_dentry_mark() to clean up and avoid redundant
node locks.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:36 -07:00
Jaegeuk Kim
01f28610a1 f2fs: fix race on allocating and deallocating a dentry block
There are two threads:
 f2fs_delete_entry()              get_new_data_page()
                                  f2fs_reserve_block()
				  dn.blkaddr = XXX
 lock_page(dentry_block)
 truncate_hole()
 dn.blkaddr = NULL
 unlock_page(dentry_block)
                                  lock_page(dentry_block)
                                  fill the block from XXX address
                                  add new dentries
                                  unlock_page(dentry_block)

Later, f2fs_write_data_page() will truncate the dentry_block, since
its block address is NULL.

The reason for this was due to the wrong lock order.
In this case, we should do f2fs_reserve_block() after locking its dentry block.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:35 -07:00
Jaegeuk Kim
eaa693f4dc f2fs: introduce dot and dotdot name check
This patch adds an inline function to check dot and dotdot names.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:34 -07:00
Jaegeuk Kim
c879f90da9 f2fs: move get_page for gc victims
This patch moves getting victim page into move_data_page.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:33 -07:00
Jaegeuk Kim
05ca3632e5 f2fs: add sbi and page pointer in f2fs_io_info
This patch adds f2fs_sb_info and page pointers in f2fs_io_info structure.
With this change, we can reduce a lot of parameters for IO functions.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:32 -07:00
Jaegeuk Kim
01b960e94a f2fs: add f2fs_may_inline_{data, dentry}
This patch adds f2fs_may_inline_data and f2fs_may_inline_dentry.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:32 -07:00
Jaegeuk Kim
06957e8fe6 f2fs: clean up f2fs_lookup
This patch cleans up to avoid deep indentation.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:31 -07:00
Jaegeuk Kim
f1e8866016 f2fs: expose f2fs_mpage_readpages
This patch implements f2fs_mpage_readpages for further optimization on
encryption support.

The basic code was taken from fs/mpage.c, and changed to be simple by adjusting
that block_size is equal to page_size in f2fs.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:30 -07:00
Jaegeuk Kim
26d815ad75 f2fs: introduce f2fs_commit_super
This patch introduces f2fs_commit_super to write updated superblock.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:29 -07:00
Jaegeuk Kim
003a3e1d60 f2fs: add f2fs_map_blocks
This patch introduces f2fs_map_blocks structure likewise ext4_map_blocks.
Now, f2fs uses f2fs_map_blocks when handling get_block.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:29 -07:00
Jaegeuk Kim
76f105a2db f2fs: add feature facility in superblock
This patch introduces a feature in superblock, which will indicate any new
features for f2fs.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:28 -07:00
Jaegeuk Kim
b5492af78c f2fs: move existing definitions into f2fs.h
This patch moves some inode-related definitions from node.h to f2fs.h to
add new features.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:27 -07:00
Brian Foster
22419ac9fe xfs: fix broken i_nlink accounting for whiteout tmpfile inode
XFS uses the internal tmpfile() infrastructure for the whiteout inode
used for RENAME_WHITEOUT operations. For tmpfile inodes, XFS allocates
the inode, drops di_nlink, adds the inode to the agi unlinked list,
calls d_tmpfile() which correspondingly drops i_nlink of the vfs inode,
and then finishes the common inode setup (e.g., clear I_NEW and unlock).

The d_tmpfile() call was originally made inxfs_create_tmpfile(), but was
pulled up out of that function as part of the following commit to
resolve a deadlock issue:

	330033d6 xfs: fix tmpfile/selinux deadlock and initialize security

As a result, callers of xfs_create_tmpfile() are responsible for either
calling d_tmpfile() or fixing up i_nlink appropriately. The whiteout
tmpfile allocation helper does neither. As a result, the vfs ->i_nlink
becomes inconsistent with the on-disk ->di_nlink once xfs_rename() links
it back into the source dentry and calls xfs_bumplink().

Update the assert in xfs_rename() to help detect this problem in the
future and update xfs_rename_alloc_whiteout() to decrement the link
count as part of the manual tmpfile inode setup.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-05-29 08:14:55 +10:00
Dave Chinner
cddc116228 xfs: xfs_iozero can return positive errno
It was missed when we converted everything in XFs to use negative error
numbers, so fix it now. Bug introduced in 3.17 by commit 2451337 ("xfs: global
error sign conversion"), and should go back to stable kernels.

Thanks to Brian Foster for noticing it.

cc: <stable@vger.kernel.org> # 3.17, 3.18, 3.19, 4.0
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-05-29 07:40:32 +10:00