Commit Graph

44162 Commits

Author SHA1 Message Date
Jaegeuk Kim
b5a7aef1ef fscrypto/f2fs: allow fs-specific key prefix for fs encryption
This patch allows fscrypto to handle a second key prefix given by filesystem.
The main reason is to provide backward compatibility, since previously f2fs
used "f2fs:" as a crypto prefix instead of "fscrypt:".
Later, ext4 should also provide key_prefix() to give "ext4:".

One concern decribed by Ted would be kinda double check overhead of prefixes.
In x86, for example, validate_user_key consumes 8 ms after boot-up, which turns
out derive_key_aes() consumed most of the time to load specific crypto module.
After such the cold miss, it shows almost zero latencies, which treats as a
negligible overhead.
Note that request_key() detects wrong prefix in prior to derive_key_aes() even.

Cc: Ted Tso <tytso@mit.edu>
Cc: stable@vger.kernel.org # v4.6
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-07 10:32:33 -07:00
Chao Yu
09210c973a f2fs: avoid panic when truncating to max filesize
The following panic occurs when truncating inode which has inline
xattr to max filesize.

[<ffffffffa013d3be>] get_dnode_of_data+0x4e/0x580 [f2fs]
[<ffffffffa013aca1>] ? read_node_page+0x51/0x90 [f2fs]
[<ffffffffa013ad99>] ? get_node_page.part.34+0xb9/0x170 [f2fs]
[<ffffffffa01235b1>] truncate_blocks+0x131/0x3f0 [f2fs]
[<ffffffffa01238e3>] f2fs_truncate+0x73/0x100 [f2fs]
[<ffffffffa01239d2>] f2fs_setattr+0x62/0x2a0 [f2fs]
[<ffffffff811a72c8>] notify_change+0x158/0x300
[<ffffffff8118a42b>] do_truncate+0x6b/0xa0
[<ffffffff8118e539>] ? __sb_start_write+0x49/0x100
[<ffffffff8118a798>] do_sys_ftruncate.constprop.12+0x118/0x170
[<ffffffff8118a82e>] SyS_ftruncate+0xe/0x10
[<ffffffff8169efcf>] tracesys+0xe1/0xe6
[<ffffffffa0139ae0>] get_node_path+0x210/0x220 [f2fs]
 <ffff880206a89ce8>
--[ end trace 5fea664dfbcc6625 ]---

The reason is truncate_blocks tries to truncate all node and data blocks
start from specified block offset with value of (max filesize / block
size), but actually, our valid max block offset is (max filesize / block
size) - 1, so f2fs detects such invalid block offset with BUG_ON in
truncation path.

This patch lets f2fs skip truncating data which is exceeding max
filesize.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-07 10:32:33 -07:00
Chao Yu
43473f9645 f2fs: fix incorrect mapping in ->bmap
Currently, generic_block_bmap is used in f2fs_bmap, its semantics is when
the mapping is been found, return position of target physical block,
otherwise return zero.

But, previously, when there is no mapping info for specified logical block,
f2fs_bmap will map target physical block to a uninitialized variable, which
should be wrong. Fix it.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-07 10:32:32 -07:00
Jaegeuk Kim
fb58ae2206 f2fs: remove an obsolete variable
This patch removes an obsolete variable used in add_free_nid.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-07 10:32:31 -07:00
Jaegeuk Kim
29234b1d6d f2fs: don't worry about inode leak in evict_inode
Even if an inode failed to release its blocks, it should be kept in an orphan
inode list, so it will be released later.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-07 10:32:30 -07:00
Chao Yu
f51b4ce6c1 f2fs: shrink size of struct seg_entry
Restructure struct seg_entry to eliminate holes in it, after that,
in 32-bits machine, it reduces size from 32 bytes to 24 bytes; in
64-bits machine, it reduces size from 56 bytes to 40 bytes.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-07 10:32:29 -07:00
Chao Yu
bd933d4fae f2fs: reuse get_extent_info
Reuse get_extent_info for readability.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-07 10:32:29 -07:00
Chao Yu
e3bc808ca8 f2fs: remove unneeded memset when updating xattr
Each of fields in struct f2fs_xattr_entry will be assigned later,
so previously we don't need to memset the struct.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-07 10:32:28 -07:00
Chao Yu
ae8d1db34f f2fs: remove unneeded readahead in find_fsync_dnodes
In find_fsync_dnodes, get_tmp_page will read dnode page synchronously,
previously, ra_meta_page did the same work, which is redundant, remove
it.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-07 10:32:27 -07:00
Jaegeuk Kim
4c0c294934 f2fs: retry to truncate blocks in -ENOMEM case
This patch modifies to retry truncating node blocks in -ENOMEM case.

Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-07 10:32:26 -07:00
Jaegeuk Kim
74ef924167 f2fs: fix leak of orphan inode objects
When unmounting filesystem, we should release all the ino entries.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-07 10:32:25 -07:00
Jaegeuk Kim
221149c00e f2fs: revisit error handling flows
This patch fixes a couple of bugs regarding to orphan inodes when handling
errors.

This tries to
 - call alloc_nid_done with add_orphan_inode in handle_failed_inode
 - let truncate blocks in f2fs_evict_inode
 - not make a bad inode due to i_mode change

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-07 10:32:25 -07:00
Jaegeuk Kim
cb78942b82 f2fs: inject ENOSPC failures
This patch injects ENOSPC failures.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-07 10:32:24 -07:00
Jaegeuk Kim
c41f3cc3ae f2fs: inject page allocation failures
This patch adds page allocation failures.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-07 10:32:23 -07:00
Jaegeuk Kim
2c63fead9e f2fs: inject kmalloc failure
This patch injects kmalloc failure given a fault injection rate.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-07 10:32:22 -07:00
Jaegeuk Kim
73faec4d99 f2fs: add mount option to select fault injection ratio
This patch adds a mount option to select fault ratio.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-07 10:32:22 -07:00
Jaegeuk Kim
300e129c15 f2fs: use f2fs_grab_cache_page instead of grab_cache_page
This patch converts grab_cache_page to f2fs_grab_cache_page.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-07 10:32:21 -07:00
Jaegeuk Kim
0414b004a8 f2fs: introduce f2fs_kmalloc to wrap kmalloc
This patch adds f2fs_kmalloc.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-07 10:32:20 -07:00
Jaegeuk Kim
f00d6fa727 f2fs: add proc entry to show valid block bitmap
This patch adds a new proc entry to show segment information in more detail.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-07 10:32:19 -07:00
Jaegeuk Kim
b7a15f3dbe f2fs: introduce macros for proc entries
This adds macros to be used multiple proc entries.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-07 10:32:18 -07:00
Chao Yu
3f8ab27085 f2fs: factor out fsync inode entry operations
Factor out fsync inode entry operations into {add,del}_fsync_inode.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-03 11:20:07 -07:00
Chao Yu
c81ced05b2 f2fs: fix to clear page private flag
Commit 28bc106b23 ("f2fs: support revoking atomic written pages")
forgot to clear page private flag correctly, fix it.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-03 11:20:06 -07:00
Chao Yu
23dc974eed f2fs: fix to clear private data in page
Private data in page should be removed during ->releasepage or
->invalidatepage, otherwise garbage data would be remained in that page.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-03 11:20:05 -07:00
Yunlong Song
fe216c7a0f f2fs: fix to return 0 if err == -ENOENT in f2fs_readdir
Commit 57b62d29ad ("f2fs: fix to report
error in f2fs_readdir") causes f2fs_readdir to return -ENOENT when
get_lock_data_page returns -ENOENT. However, the original logic is to
continue when get_lock_data_page returns -ENOENT, but it forgets to
reset err to 0.

This will cause getdents64 incorretly return -ENOENT when lastdirent is
NULL in getdents64. This will lead to a wrong return value for syscall
caller.

Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-04-27 14:10:43 -07:00
Chao Yu
da011cc0da f2fs: move node pages only in victim section during GC
For foreground GC, we cache node blocks in victim section and set them
dirty, then we call sync_node_pages to flush these node pages, but
meanwhile, those node pages which does not locate in victim section
will be flushed together, so more bandwidth and continuous free space
would be occupied.

So for this condition, it's better to leave those unrelated node page
in cache for further write hit, and let CP or VM to flush them afterward.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-04-27 14:10:42 -07:00
Chao Yu
a4a13f582c f2fs: be aware of invalid filename length
The filename length in dirent of may become zero-sized after random junk
data injection, once encounter such dirent, find_target_dentry or
f2fs_add_inline_entries will run into an infinite loop. So let f2fs being
aware of that to avoid deadloop.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-04-27 14:10:42 -07:00
Jaegeuk Kim
6bfc49197e f2fs: issue cache flush on direct IO
Under direct IO path with O_(D)SYNC, it needs to set proper APPEND or UPDATE
flags, so taht f2fs_sync_file can make its data safe.

Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-04-26 14:25:05 -07:00
Jaegeuk Kim
608514deba f2fs: set fsync mark only for the last dnode
In order to give atomic writes, we should consider power failure during
sync_node_pages in fsync.
So, this patch marks fsync flag only in the last dnode block.

Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-04-26 14:24:59 -07:00
Jaegeuk Kim
c267ec1526 f2fs: report unwritten status in fsync_node_pages
The fsync_node_pages should return pass or failure so that user could know
fsync is completed or not.

Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-04-26 14:24:54 -07:00
Jaegeuk Kim
5268137564 f2fs: split sync_node_pages with fsync_node_pages
This patch splits the existing sync_node_pages into (f)sync_node_pages.
The fsync_node_pages is used for f2fs_sync_file only.

Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-04-26 14:24:48 -07:00
Jaegeuk Kim
e6e5f5610d f2fs: avoid writing 0'th page in volatile writes
The first page of volatile writes usually contains a sort of header information
which will be used for recovery.
(e.g., journal header of sqlite)

If this is written without other journal data, user needs to handle the stale
journal information.

Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-04-26 14:24:39 -07:00
Jaegeuk Kim
eca76e783c f2fs: avoid needless lock for node pages when fsyncing a file
When fsync is called, sync_node_pages finds a proper direct node pages to flush.
But, it locks unrelated direct node pages together unnecessarily.

Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-04-26 14:24:30 -07:00
Jaegeuk Kim
c27753d675 f2fs: flush dirty pages before starting atomic writes
If somebody wrote some data before atomic writes, we should flush them in order
to handle atomic data in a right period.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-04-15 08:50:25 -07:00
Jaegeuk Kim
63c52d7878 f2fs: don't invalidate atomic page if successful
If we committed atomic write successfully, we don't need to invalidate pages.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-04-15 08:50:25 -07:00
Jaegeuk Kim
58457f1c35 f2fs: give -E2BIG for no space in xattr
This patch returns -E2BIG if there is no space to add an xattr entry.
This should fix generic/026 in xfstests as well.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-04-15 08:50:25 -07:00
Jaegeuk Kim
4da7bf5a43 f2fs: remove redundant condition check
This patch resolves the redundant condition check reported by David.

Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-04-15 08:49:47 -07:00
Jaegeuk Kim
26dc3d4424 f2fs: unset atomic/volatile flag in f2fs_release_file
The atomic/volatile operation should be done in pair of start and commit
ioctl.
For example, if a killed process remains open-ended atomic operation, we should
drop its flag as well as its atomic data. Otherwise, if sqlite initiates another
operation which doesn't require atomic writes, it will lose every data, since
f2fs still treats with them as atomic writes; nobody will trigger its commit.

Reported-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-04-15 08:49:47 -07:00
Jaegeuk Kim
de5307e46d f2fs: fix dropping inmemory pages in a wrong time
When one reader closes its file while the other writer is doing atomic writes,
f2fs_release_file drops atomic data resulting in an empty commit.
This patch fixes this wrong commit problem by checking openess of the file.

 Process0                       Process1
 				open file
 start atomic write
 write data
 read data
				close file
				f2fs_release_file()
				clear atomic data
 commit atomic write

Reported-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-04-15 08:49:47 -07:00
Jaegeuk Kim
ff37355886 f2fs: add BUG_ON to avoid unnecessary flow
This patch adds BUG_ON instead of retrying loop.
In the case of node pages, we already got this inode page, but unlocked it.
By the fact that we don't truncate any node pages in operations, the page's
mapping should be unchangeable.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-04-15 08:49:47 -07:00
Jaegeuk Kim
4a6de50d54 f2fs: use PGP_LOCK to check its truncation
Previously, after trylock_page is succeeded, it doesn't check its mapping.
In order to fix that, we can just give PGP_LOCK to pagecache_get_page.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-04-15 08:49:47 -07:00
Chao Yu
675f10bde6 f2fs: fix to convert inline directory correctly
With below serials, we will lose parts of dirents:

1) mount f2fs with inline_dentry option
2) echo 1 > /sys/fs/f2fs/sdX/dir_level
3) mkdir dir
4) touch 180 files named [1-180] in dir
5) touch 181 in dir
6) echo 3 > /proc/sys/vm/drop_caches
7) ll dir

ls: cannot access 2: No such file or directory
ls: cannot access 4: No such file or directory
ls: cannot access 5: No such file or directory
ls: cannot access 6: No such file or directory
ls: cannot access 8: No such file or directory
ls: cannot access 9: No such file or directory
...
total 360
drwxr-xr-x 2 root root 4096 Feb 19 15:12 ./
drwxr-xr-x 3 root root 4096 Feb 19 15:11 ../
-rw-r--r-- 1 root root    0 Feb 19 15:12 1
-rw-r--r-- 1 root root    0 Feb 19 15:12 10
-rw-r--r-- 1 root root    0 Feb 19 15:12 100
-????????? ? ?    ?       ?            ? 101
-????????? ? ?    ?       ?            ? 102
-????????? ? ?    ?       ?            ? 103
...

The reason is: when doing the inline dir conversion, we didn't consider
that directory has hierarchical hash structure which can be configured
through sysfs interface 'dir_level'.

By default, dir_level of directory inode is 0, it means we have one bucket
in hash table located in first level, all dirents will be hashed in this
bucket, so it has no problem for us to do the duplication simply between
inline dentry page and converted normal dentry page.

However, if we configured dir_level with the value N (greater than 0), it
will expand the bucket number of first level hash table by 2^N - 1, it
hashs dirents into different buckets according their hash value, if we
still move all dirents to first bucket, it makes incorrent locating for
inline dirents, the result is, although we can iterate all dirents through
->readdir, we can't stat some of them in ->lookup which based on hash
table searching.

This patch fixes this issue by rehashing dirents into correct position
when converting inline directory.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-04-15 08:49:47 -07:00
Jaegeuk Kim
8c11a53fc2 f2fs: show current mount status
This patch remains the current mount status to f2fs status info.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-04-15 08:49:47 -07:00
Jaegeuk Kim
faa0e55bba f2fs: treat as a normal umount when remounting ro
When user remounts f2fs as read-only, we can mark the checkpoint as umount.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-04-15 08:49:47 -07:00
Jaegeuk Kim
6781eabba1 f2fs: give -EINVAL for norecovery and rw mount
Once detecting something to recover, f2fs should stop mounting, given norecovery
and rw mount options.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-04-15 08:49:47 -07:00
Jaegeuk Kim
df728b0f69 f2fs: recover superblock at RW remounts
This patch adds a sbi flag, SBI_NEED_SB_WRITE, which indicates it needs to
recover superblock when (re)mounting as RW. This is set only when f2fs is
mounted as RO.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-04-15 08:49:47 -07:00
Jaegeuk Kim
f2353d7bd4 f2fs: give RO message when recovering superblock
When one of superblocks is missing, f2fs recovers it with the valid one.
But, even if f2fs is mounted as RO, we'd better notify that too.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-04-15 08:49:47 -07:00
Linus Torvalds
dfe70581c1 for-linus-4.6-rc4
These patches fix f2fs and fscrypto based on -rc3 bug fixes in ext4 crypto,
 which have not yet been fully propagated as follows.
  - use of dget_parent and file_dentry to avoid crashes
  - disallow RCU-mode lookup in d_invalidate
  - disallow -ENOMEM in the core data encryption path
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Merge tag 'for-linus-4.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

Pull f2fs/fscrypto fixes from Jaegeuk Kim:
 "In addition to f2fs/fscrypto fixes, I've added one patch which
  prevents RCU mode lookup in d_revalidate, as Al mentioned.

  These patches fix f2fs and fscrypto based on -rc3 bug fixes in ext4
  crypto, which have not yet been fully propagated as follows.

   - use of dget_parent and file_dentry to avoid crashes
   - disallow RCU-mode lookup in d_invalidate
   - disallow -ENOMEM in the core data encryption path"

* tag 'for-linus-4.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs:
  ext4/fscrypto: avoid RCU lookup in d_revalidate
  fscrypto: don't let data integrity writebacks fail with ENOMEM
  f2fs: use dget_parent and file_dentry in f2fs_file_open
  fscrypto: use dget_parent() in fscrypt_d_revalidate()
2016-04-14 18:22:42 -07:00
Linus Torvalds
34dbbcdbf6 Make file credentials available to the seqfile interfaces
A lot of seqfile users seem to be using things like %pK that uses the
credentials of the current process, but that is actually completely
wrong for filesystem interfaces.

The unix semantics for permission checking files is to check permissions
at _open_ time, not at read or write time, and that is not just a small
detail: passing off stdin/stdout/stderr to a suid application and making
the actual IO happen in privileged context is a classic exploit
technique.

So if we want to be able to look at permissions at read time, we need to
use the file open credentials, not the current ones.  Normal file
accesses can just use "f_cred" (or any of the helper functions that do
that, like file_ns_capable()), but the seqfile interfaces do not have
any such options.

It turns out that seq_file _does_ save away the user_ns information of
the file, though.  Since user_ns is just part of the full credential
information, replace that special case with saving off the cred pointer
instead, and suddenly seq_file has all the permission information it
needs.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-14 12:56:09 -07:00
Jaegeuk Kim
03a8bb0e53 ext4/fscrypto: avoid RCU lookup in d_revalidate
As Al pointed, d_revalidate should return RCU lookup before using d_inode.
This was originally introduced by:
commit 34286d6662 ("fs: rcu-walk aware d_revalidate method").

Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: stable <stable@vger.kernel.org>
2016-04-12 20:01:35 -07:00
Jaegeuk Kim
b32e4482aa fscrypto: don't let data integrity writebacks fail with ENOMEM
This patch fixes the issue introduced by the ext4 crypto fix in a same manner.
For F2FS, however, we flush the pending IOs and wait for a while to acquire free
memory.

Fixes: c9af28fdd4 ("ext4 crypto: don't let data integrity writebacks fail with ENOMEM")
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-04-12 10:25:30 -07:00