Commit Graph

199 Commits

Author SHA1 Message Date
Chao Yu
fe76a166a1 f2fs: introduce f2fs_match_name() for cleanup
This patch introduces f2fs_match_name() for cleanup.

BTW, it avoids to fallback to normal comparison once it doesn't
match casefolded name.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-08-23 07:57:15 -07:00
Daniel Rosenberg
2c2eb7a300 f2fs: Support case-insensitive file name lookups
Modeled after commit b886ee3e77 ("ext4: Support case-insensitive file
name lookups")

"""
This patch implements the actual support for case-insensitive file name
lookups in f2fs, based on the feature bit and the encoding stored in the
superblock.

A filesystem that has the casefold feature set is able to configure
directories with the +F (F2FS_CASEFOLD_FL) attribute, enabling lookups
to succeed in that directory in a case-insensitive fashion, i.e: match
a directory entry even if the name used by userspace is not a byte per
byte match with the disk name, but is an equivalent case-insensitive
version of the Unicode string.  This operation is called a
case-insensitive file name lookup.

The feature is configured as an inode attribute applied to directories
and inherited by its children.  This attribute can only be enabled on
empty directories for filesystems that support the encoding feature,
thus preventing collision of file names that only differ by case.

* dcache handling:

For a +F directory, F2Fs only stores the first equivalent name dentry
used in the dcache. This is done to prevent unintentional duplication of
dentries in the dcache, while also allowing the VFS code to quickly find
the right entry in the cache despite which equivalent string was used in
a previous lookup, without having to resort to ->lookup().

d_hash() of casefolded directories is implemented as the hash of the
casefolded string, such that we always have a well-known bucket for all
the equivalencies of the same string. d_compare() uses the
utf8_strncasecmp() infrastructure, which handles the comparison of
equivalent, same case, names as well.

For now, negative lookups are not inserted in the dcache, since they
would need to be invalidated anyway, because we can't trust missing file
dentries.  This is bad for performance but requires some leveraging of
the vfs layer to fix.  We can live without that for now, and so does
everyone else.

* on-disk data:

Despite using a specific version of the name as the internal
representation within the dcache, the name stored and fetched from the
disk is a byte-per-byte match with what the user requested, making this
implementation 'name-preserving'. i.e. no actual information is lost
when writing to storage.

DX is supported by modifying the hashes used in +F directories to make
them case/encoding-aware.  The new disk hashes are calculated as the
hash of the full casefolded string, instead of the string directly.
This allows us to efficiently search for file names in the htree without
requiring the user to provide an exact name.

* Dealing with invalid sequences:

By default, when a invalid UTF-8 sequence is identified, ext4 will treat
it as an opaque byte sequence, ignoring the encoding and reverting to
the old behavior for that unique file.  This means that case-insensitive
file name lookup will not work only for that file.  An optional bit can
be set in the superblock telling the filesystem code and userspace tools
to enforce the encoding.  When that optional bit is set, any attempt to
create a file name using an invalid UTF-8 sequence will fail and return
an error to userspace.

* Normalization algorithm:

The UTF-8 algorithms used to compare strings in f2fs is implemented
in fs/unicode, and is based on a previous version developed by
SGI.  It implements the Canonical decomposition (NFD) algorithm
described by the Unicode specification 12.1, or higher, combined with
the elimination of ignorable code points (NFDi) and full
case-folding (CF) as documented in fs/unicode/utf8_norm.c.

NFD seems to be the best normalization method for F2FS because:

  - It has a lower cost than NFC/NFKC (which requires
    decomposing to NFD as an intermediary step)
  - It doesn't eliminate important semantic meaning like
    compatibility decompositions.

Although:

- This implementation is not completely linguistic accurate, because
different languages have conflicting rules, which would require the
specialization of the filesystem to a given locale, which brings all
sorts of problems for removable media and for users who use more than
one language.
"""

Signed-off-by: Daniel Rosenberg <drosen@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-08-23 07:57:13 -07:00
Chao Yu
10f966bbf5 f2fs: use generic EFSBADCRC/EFSCORRUPTED
f2fs uses EFAULT as error number to indicate filesystem is corrupted
all the time, but generic filesystems use EUCLEAN for such condition,
we need to change to follow others.

This patch adds two new macros as below to wrap more generic error
code macros, and spread them in code.

EFSBADCRC	EBADMSG		/* Bad CRC detected */
EFSCORRUPTED	EUCLEAN		/* Filesystem is corrupted */

Reported-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-07-02 15:40:41 -07:00
Joe Perches
dcbb4c10e6 f2fs: introduce f2fs_<level> macros to wrap f2fs_printk()
- Add and use f2fs_<level> macros
- Convert f2fs_msg to f2fs_printk
- Remove level from f2fs_printk and embed the level in the format
- Coalesce formats and align multi-line arguments
- Remove unnecessary duplicate extern f2fs_msg f2fs.h

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-07-02 15:40:40 -07:00
Chao Yu
36af5f407b f2fs: fix sparse warning
make C=2 CHECKFLAGS="-D__CHECK_ENDIAN__"

CHECK   dir.c
dir.c:842:50: warning: cast from restricted __le32
CHECK   node.c
node.c:2759:40: warning: restricted __le32 degrades to integer

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-05-30 09:48:45 -07:00
Linus Torvalds
5160bcce5c f2fs-for-5.1-rc1
We've continued mainly to fix bugs in this round, as f2fs has been shipped
 in more devices. Especially, we've focused on stabilizing checkpoint=disable
 feature, and provided some interfaces for QA.
 
 Enhancement:
  - expose FS_NOCOW_FL for pin_file
  - run discard jobs at unmount time with timeout
  - tune discarding thread to avoid idling which consumes power
  - some checking codes to address vulnerabilities
  - give random value to i_generation
  - shutdown with more flags for QA
 
 Bug fix:
  - clean up stale objects when mount is failed along with checkpoint=disable
  - fix system being stuck due to wrong count by atomic writes
  - handle some corrupted disk cases
  - fix a deadlock in f2fs_read_inline_dir
 
 We've also added some minor build errors and clean-up patches.
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Merge tag 'f2fs-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

Pull f2fs updates from Jaegeuk Kim:
 "We've continued mainly to fix bugs in this round, as f2fs has been
  shipped in more devices. Especially, we've focused on stabilizing
  checkpoint=disable feature, and provided some interfaces for QA.

  Enhancements:
   - expose FS_NOCOW_FL for pin_file
   - run discard jobs at unmount time with timeout
   - tune discarding thread to avoid idling which consumes power
   - some checking codes to address vulnerabilities
   - give random value to i_generation
   - shutdown with more flags for QA

  Bug fixes:
   - clean up stale objects when mount is failed along with
     checkpoint=disable
   - fix system being stuck due to wrong count by atomic writes
   - handle some corrupted disk cases
   - fix a deadlock in f2fs_read_inline_dir

  We've also added some minor build error fixes and clean-up patches"

* tag 'f2fs-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (53 commits)
  f2fs: set pin_file under CAP_SYS_ADMIN
  f2fs: fix to avoid deadlock in f2fs_read_inline_dir()
  f2fs: fix to adapt small inline xattr space in __find_inline_xattr()
  f2fs: fix to do sanity check with inode.i_inline_xattr_size
  f2fs: give some messages for inline_xattr_size
  f2fs: don't trigger read IO for beyond EOF page
  f2fs: fix to add refcount once page is tagged PG_private
  f2fs: remove wrong comment in f2fs_invalidate_page()
  f2fs: fix to use kvfree instead of kzfree
  f2fs: print more parameters in trace_f2fs_map_blocks
  f2fs: trace f2fs_ioc_shutdown
  f2fs: fix to avoid deadlock of atomic file operations
  f2fs: fix to dirty inode for i_mode recovery
  f2fs: give random value to i_generation
  f2fs: no need to take page lock in readdir
  f2fs: fix to update iostat correctly in IPU path
  f2fs: fix encrypted page memory leak
  f2fs: make fault injection covering __submit_flush_wait()
  f2fs: fix to retry fill_super only if recovery failed
  f2fs: silence VM_WARN_ON_ONCE in mempool_alloc
  ...
2019-03-15 13:42:53 -07:00
Chao Yu
240a59156d f2fs: fix to add refcount once page is tagged PG_private
As Gao Xiang reported in bugzilla:

https://bugzilla.kernel.org/show_bug.cgi?id=202749

f2fs may skip pageout() due to incorrect page reference count.

The problem here is that MM defined the rule [1] very clearly that
once page was set with PG_private flag, we should increment the
refcount in that page, also main flows like pageout(), migrate_page()
will assume there is one additional page reference count if
page_has_private() returns true.

But currently, f2fs won't add/del refcount when changing PG_private
flag. Anyway, f2fs should follow MM's rule to make MM's related flows
running as expected.

[1] https://lore.kernel.org/lkml/2b19b3c4-2bc4-15fa-15cc-27a13e5c7af1@aol.com/

Reported-by: Gao Xiang <gaoxiang25@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-03-12 18:59:19 -07:00
Gao Xiang
613f3dcdf0 f2fs: no need to take page lock in readdir
VFS will take inode_lock for readdir, therefore no need to
take page lock in readdir at all just as the majority of
other generic filesystems.

This patch improves concurrency since .iterate_shared
was introduced to VFS years ago.

Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-03-12 18:59:18 -07:00
Chandan Rajendra
62230e0d70 f2fs: use IS_ENCRYPTED() to check encryption status
This commit removes the f2fs specific f2fs_encrypted_inode() and makes
use of the generic IS_ENCRYPTED() macro to check for the encryption
status of an inode.

Acked-by: Chao Yu <yuchao0@huawei.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
2019-01-23 23:56:43 -05:00
Sheng Yong
720db06863 f2fs: check if file namelen exceeds max value
Dentry bitmap is not enough to detect incorrect dentries. So this patch
also checks the namelen value of a dentry.

Signed-off-by: Gong Chen <gongchen4@huawei.com>
Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-01-22 15:31:26 -08:00
Chao Yu
ddf06b753a f2fs: fix to trigger fsck if dirent.name_len is zero
While traversing dirents in f2fs_fill_dentries(), if bitmap is valid,
filename length should not be zero, otherwise, directory structure
consistency could be corrupted, in this case, let's print related
info and set SBI_NEED_FSCK to trigger fsck for repairing.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-01-22 15:31:25 -08:00
Chao Yu
bae0ee7a76 f2fs: check PageWriteback flag for ordered case
For all ordered cases in f2fs_wait_on_page_writeback(), we need to
check PageWriteback status, so let's clean up to relocate the check
into f2fs_wait_on_page_writeback().

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-12-26 15:16:56 -08:00
Jaegeuk Kim
4e240d1bab f2fs: check memory boundary by insane namelen
If namelen is corrupted to have very long value, fill_dentries can copy
wrong memory area.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-11-26 15:53:57 -08:00
Linus Torvalds
dad4f140ed Merge branch 'xarray' of git://git.infradead.org/users/willy/linux-dax
Pull XArray conversion from Matthew Wilcox:
 "The XArray provides an improved interface to the radix tree data
  structure, providing locking as part of the API, specifying GFP flags
  at allocation time, eliminating preloading, less re-walking the tree,
  more efficient iterations and not exposing RCU-protected pointers to
  its users.

  This patch set

   1. Introduces the XArray implementation

   2. Converts the pagecache to use it

   3. Converts memremap to use it

  The page cache is the most complex and important user of the radix
  tree, so converting it was most important. Converting the memremap
  code removes the only other user of the multiorder code, which allows
  us to remove the radix tree code that supported it.

  I have 40+ followup patches to convert many other users of the radix
  tree over to the XArray, but I'd like to get this part in first. The
  other conversions haven't been in linux-next and aren't suitable for
  applying yet, but you can see them in the xarray-conv branch if you're
  interested"

* 'xarray' of git://git.infradead.org/users/willy/linux-dax: (90 commits)
  radix tree: Remove multiorder support
  radix tree test: Convert multiorder tests to XArray
  radix tree tests: Convert item_delete_rcu to XArray
  radix tree tests: Convert item_kill_tree to XArray
  radix tree tests: Move item_insert_order
  radix tree test suite: Remove multiorder benchmarking
  radix tree test suite: Remove __item_insert
  memremap: Convert to XArray
  xarray: Add range store functionality
  xarray: Move multiorder_check to in-kernel tests
  xarray: Move multiorder_shrink to kernel tests
  xarray: Move multiorder account test in-kernel
  radix tree test suite: Convert iteration test to XArray
  radix tree test suite: Convert tag_tagged_items to XArray
  radix tree: Remove radix_tree_clear_tags
  radix tree: Remove radix_tree_maybe_preload_order
  radix tree: Remove split/join code
  radix tree: Remove radix_tree_update_node_t
  page cache: Finish XArray conversion
  dax: Convert page fault handlers to XArray
  ...
2018-10-28 11:35:40 -07:00
Chao Yu
2baf078185 f2fs: fix to spread clear_cold_data()
We need to drop PG_checked flag on page as well when we clear PG_uptodate
flag, in order to avoid treating the page as GCing one later.

Signed-off-by: Weichao Guo <guoweichao@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-10-22 17:54:46 -07:00
Matthew Wilcox
5ec2d99de7 f2fs: Convert to XArray
This is a straightforward conversion.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:42 -04:00
Sahitya Tummala
c75f2feb80 f2fs: do not update REQ_TIME in case of error conditions
The REQ_TIME should be updated only in case of success cases
as followed at all other places in the file system.

Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-10-16 09:37:00 -07:00
Chao Yu
7c1a000d46 f2fs: add SPDX license identifiers
Remove the verbose license text from f2fs files and replace them with
SPDX tags.  This does not change the license of any of the code.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-09-12 13:07:10 -07:00
Chao Yu
e1293bdfa0 f2fs: plug readahead IO in readdir()
Add a plug to merge readahead IO in readdir(), expecting it can
reduce bio count before submitting to block layer.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-09-11 17:09:32 -07:00
Arnd Bergmann
7fa750a163 f2fs: rework fault injection handling to avoid a warning
When CONFIG_F2FS_FAULT_INJECTION is disabled, we get a warning about an
unused label:

fs/f2fs/segment.c: In function '__submit_discard_cmd':
fs/f2fs/segment.c:1059:1: error: label 'submit' defined but not used [-Werror=unused-label]

This could be fixed by adding another #ifdef around it, but the more
reliable way of doing this seems to be to remove the other #ifdefs
where that is easily possible.

By defining time_to_inject() as a trivial stub, most of the checks for
CONFIG_F2FS_FAULT_INJECTION can go away. This also leads to nicer
formatting of the code.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-08-14 09:49:15 -07:00
Chao Yu
4d57b86dd8 f2fs: clean up symbol namespace
As Ted reported:

"Hi, I was looking at f2fs's sources recently, and I noticed that there
is a very large number of non-static symbols which don't have a f2fs
prefix.  There's well over a hundred (see attached below).

As one example, in fs/f2fs/dir.c there is:

unsigned char get_de_type(struct f2fs_dir_entry *de)

This function is clearly only useful for f2fs, but it has a generic
name.  This means that if any other file system tries to have the same
symbol name, there will be a symbol conflict and the kernel would not
successfully build.  It also means that when someone is looking f2fs
sources, it's not at all obvious whether a function such as
read_data_page(), invalidate_blocks(), is a generic kernel function
found in the fs, mm, or block layers, or a f2fs specific function.

You might want to fix this at some point.  Hopefully Kent's bcachefs
isn't similarly using genericly named functions, since that might
cause conflicts with f2fs's functions --- but just as this would be a
problem that we would rightly insist that Kent fix, this is something
that we should have rightly insisted that f2fs should have fixed
before it was integrated into the mainline kernel.

acquire_orphan_inode
add_ino_entry
add_orphan_inode
allocate_data_block
allocate_new_segments
alloc_nid
alloc_nid_done
alloc_nid_failed
available_free_memory
...."

This patch adds "f2fs_" prefix for all non-static symbols in order to:
a) avoid conflict with other kernel generic symbols;
b) to indicate the function is f2fs specific one instead of generic
one;

Reported-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-05-31 11:31:53 -07:00
Chao Yu
2e79d951ff f2fs: make set_de_type() static
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-05-31 11:31:53 -07:00
Chao Yu
aec2f729fc f2fs: clean up with clear_radix_tree_dirty_tag
Introduce clear_radix_tree_dirty_tag to include common codes for cleanup.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-05-31 11:31:52 -07:00
Matthew Wilcox
b93b016313 page cache: use xa_lock
Remove the address_space ->tree_lock and use the xa_lock newly added to
the radix_tree_root.  Rename the address_space ->page_tree to ->i_pages,
since we don't really care that it's a tree.

[willy@infradead.org: fix nds32, fs/dax.c]
  Link: http://lkml.kernel.org/r/20180406145415.GB20605@bombadil.infradead.orgLink: http://lkml.kernel.org/r/20180313132639.17387-9-willy@infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:39 -07:00
Sheng Yong
ff62af200b f2fs: introduce a new mount option test_dummy_encryption
This patch introduces a new mount option `test_dummy_encryption'
to allow fscrypt to create a fake fscrypt context. This is used
by xfstests.

Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-03-17 14:02:57 +09:00
Chao Yu
c56675750d f2fs: remove unneeded set_cold_node()
When setting COLD_BIT_SHIFT flag in node block, we only need to call
set_cold_node() in new_node_page() and recover_inode_page() during
node page initialization. So remove unneeded set_cold_node() in other
places.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-03-17 13:57:33 +09:00
Chao Yu
63189b7859 f2fs: wrap all options with f2fs_sb_info.mount_opt
This patch merges miscellaneous mount options into struct f2fs_mount_info,
After this patch, once we add new mount option, we don't need to worry
about recovery of it in remount_fs(), since we will recover the
f2fs_sb_info.mount_opt including all options.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-03-17 13:57:30 +09:00
Junling Zheng
93cf93f17c f2fs: introduce mount option for fsync mode
Commit "0a007b97aad6"(f2fs: recover directory operations by fsync)
fixed xfstest generic/342 case, but it also increased the written
data and caused the performance degradation. In most cases, there's
no need to do so heavy fsync actually.

So we introduce new mount option "fsync_mode={posix,strict}" to
control the policy of fsync. "fsync_mode=posix" is set by default,
and means that f2fs uses a light fsync, which follows POSIX semantics.
And "fsync_mode=strict" means that it's a heavy fsync, which behaves
in line with xfs, ext4 and btrfs, where generic/342 will pass, but
the performance will regress.

Signed-off-by: Junling Zheng <zhengjunling@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-03-17 13:57:28 +09:00
Yunlong Song
bdbc90fa55 f2fs: don't put dentry page in pagecache into highmem
Previous dentry page uses highmem, which will cause panic in platforms
using highmem (such as arm), since the address space of dentry pages
from highmem directly goes into the decryption path via the function
fscrypt_fname_disk_to_usr. But sg_init_one assumes the address is not
from highmem, and then cause panic since it doesn't call kmap_high but
kunmap_high is triggered at the end. To fix this problem in a simple
way, this patch avoids to put dentry page in pagecache into highmem.

Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
[Jaegeuk Kim: fix coding style]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-03-13 08:05:03 +09:00
Jaegeuk Kim
0a007b97aa f2fs: recover directory operations by fsync
This fixes generic/342 which doesn't recover renamed file which was fsynced
before. It will be done via another fsync on newly created file.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-01-02 19:27:31 -08:00
Sheng Yong
f6df8f234e f2fs: introduce sysfs readdir_ra to readahead inode block in readdir
This patch introduces a sysfs interface readdir_ra to enable/disable
readaheading inode block in f2fs_readdir. When readdir_ra is enabled,
it improves the performance of "readdir + stat".

For 300,000 files:
	time find /data/test > /dev/null
disable readdir_ra: 1m25.69s real  0m01.94s user  0m50.80s system
enable  readdir_ra: 0m18.55s real  0m00.44s user  0m15.39s system

Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-01-02 19:27:27 -08:00
Chao Yu
ab383be510 f2fs: update ctx->pos correctly when hitting hole in directory
This patch fixes to update ctx->pos correctly when hitting hole in
directory.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-10-26 10:44:20 +02:00
Chao Yu
cb7a844865 f2fs: relocate readahead codes in readdir()
Previously, for large directory, we just do readahead only once in
readdir(), readdir()'s performance may drop when traversing latter
blocks. In order to avoid this, relocate readahead codes to covering
all traverse flow.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-10-26 10:44:19 +02:00
Chao Yu
4414dea8d3 f2fs: allow readdir() to be interrupted
This patch follows ext4 to allow readdir() in large empty directory to
be interrupted. Referenced commit of ext4: 1f60fbe727 ("ext4: allow
readdir()'s of large empty directories to be interrupted").

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-10-26 10:44:18 +02:00
Chao Yu
e97a3c4c6f f2fs: trace f2fs_readdir
This patch adds trace for f2fs_readdir.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-10-26 10:44:17 +02:00
Daeho Jeong
0abd8e70d2 f2fs: clear radix tree dirty tag of pages whose dirty flag is cleared
On a senario like writing out the first dirty page of the inode
as the inline data, we only cleared dirty flags of the pages, but
didn't clear the dirty tags of those pages in the radix tree.

If we don't clear the dirty tags of the pages in the radix tree, the
inodes which contain the pages will be marked with I_DIRTY_PAGES again
and again, and writepages() for the inodes will be invoked in every
writeback period. As a result, nothing will be done in every
writepages() for the inodes and it will just consume CPU time
meaninglessly.

Signed-off-by: Daeho Jeong <daeho.jeong@samsung.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-09-11 21:32:38 -07:00
Sheng Yong
d58dfb7505 f2fs: do not set LOST_PINO for newly created dir
Since directories will be written back with checkpoint and fsync a
directory will always write CP, there is no need to set LOST_PINO
after creating a directory.

Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-07-07 10:34:45 -07:00
Linus Torvalds
70ef8f0d37 for-f2fs-4.12
In this round, we've focused on enhancing performance with regards to block
 allocation, GC, and discard/in-place-update IO controls. There are a bunch
 of clean-ups as well as minor bug fixes.
 
 = Enhancement
 - disable heap-based allocation by default
 - issue small-sized discard commands by default
 - change the policy of data hotness for logging
 - distinguish IOs in terms of size and wbc type
 - start SSR earlier to avoid foreground GC
 - enhance data structures managing discard commands
 - enhance in-place update flow
 - add some more fault injection routines
 - secure one more xattr entry
 
 = Bug fix
 - calculate victim cost for GC correctly
 - remain correct victim segment number for GC
 - race condition in nid allocator and initializer
 - stale pointer produced by atomic_writes
 - fix missing REQ_SYNC for flush commands
 - handle missing errors in more corner cases
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Merge tag 'for-f2fs-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

Pull f2fs updates from Jaegeuk Kim:
 "In this round, we've focused on enhancing performance with regards to
  block allocation, GC, and discard/in-place-update IO controls. There
  are a bunch of clean-ups as well as minor bug fixes.

  Enhancements:
   - disable heap-based allocation by default
   - issue small-sized discard commands by default
   - change the policy of data hotness for logging
   - distinguish IOs in terms of size and wbc type
   - start SSR earlier to avoid foreground GC
   - enhance data structures managing discard commands
   - enhance in-place update flow
   - add some more fault injection routines
   - secure one more xattr entry

  Bug fixes:
   - calculate victim cost for GC correctly
   - remain correct victim segment number for GC
   - race condition in nid allocator and initializer
   - stale pointer produced by atomic_writes
   - fix missing REQ_SYNC for flush commands
   - handle missing errors in more corner cases"

* tag 'for-f2fs-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (111 commits)
  f2fs: fix a mount fail for wrong next_scan_nid
  f2fs: enhance scalability of trace macro
  f2fs: relocate inode_{,un}lock in F2FS_IOC_SETFLAGS
  f2fs: Make flush bios explicitely sync
  f2fs: show available_nids in f2fs/status
  f2fs: flush dirty nats periodically
  f2fs: introduce CP_TRIMMED_FLAG to avoid unneeded discard
  f2fs: allow cpc->reason to indicate more than one reason
  f2fs: release cp and dnode lock before IPU
  f2fs: shrink size of struct discard_cmd
  f2fs: don't hold cmd_lock during waiting discard command
  f2fs: nullify fio->encrypted_page for each writes
  f2fs: sanity check segment count
  f2fs: introduce valid_ipu_blkaddr to clean up
  f2fs: lookup extent cache first under IPU scenario
  f2fs: reconstruct code to write a data page
  f2fs: introduce __wait_discard_cmd
  f2fs: introduce __issue_discard_cmd
  f2fs: enable small discard by default
  f2fs: delay awaking discard thread
  ...
2017-05-08 12:24:17 -07:00
Eric Biggers
1f73d49177 f2fs: switch to using fscrypt_match_name()
Switch f2fs directory searches to use the fscrypt_match_name() helper
function.  There should be no functional change.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-04 11:44:39 -04:00
Eric Biggers
6b06cdee81 fscrypt: avoid collisions when presenting long encrypted filenames
When accessing an encrypted directory without the key, userspace must
operate on filenames derived from the ciphertext names, which contain
arbitrary bytes.  Since we must support filenames as long as NAME_MAX,
we can't always just base64-encode the ciphertext, since that may make
it too long.  Currently, this is solved by presenting long names in an
abbreviated form containing any needed filesystem-specific hashes (e.g.
to identify a directory block), then the last 16 bytes of ciphertext.
This needs to be sufficient to identify the actual name on lookup.

However, there is a bug.  It seems to have been assumed that due to the
use of a CBC (ciphertext block chaining)-based encryption mode, the last
16 bytes (i.e. the AES block size) of ciphertext would depend on the
full plaintext, preventing collisions.  However, we actually use CBC
with ciphertext stealing (CTS), which handles the last two blocks
specially, causing them to appear "flipped".  Thus, it's actually the
second-to-last block which depends on the full plaintext.

This caused long filenames that differ only near the end of their
plaintexts to, when observed without the key, point to the wrong inode
and be undeletable.  For example, with ext4:

    # echo pass | e4crypt add_key -p 16 edir/
    # seq -f "edir/abcdefghijklmnopqrstuvwxyz012345%.0f" 100000 | xargs touch
    # find edir/ -type f | xargs stat -c %i | sort | uniq | wc -l
    100000
    # sync
    # echo 3 > /proc/sys/vm/drop_caches
    # keyctl new_session
    # find edir/ -type f | xargs stat -c %i | sort | uniq | wc -l
    2004
    # rm -rf edir/
    rm: cannot remove 'edir/_A7nNFi3rhkEQlJ6P,hdzluhODKOeWx5V': Structure needs cleaning
    ...

To fix this, when presenting long encrypted filenames, encode the
second-to-last block of ciphertext rather than the last 16 bytes.

Although it would be nice to solve this without depending on a specific
encryption mode, that would mean doing a cryptographic hash like SHA-256
which would be much less efficient.  This way is sufficient for now, and
it's still compatible with encryption modes like HEH which are strong
pseudorandom permutations.  Also, changing the presented names is still
allowed at any time because they are only provided to allow applications
to do things like delete encrypted directories.  They're not designed to
be used to persistently identify files --- which would be hard to do
anyway, given that they're encrypted after all.

For ease of backports, this patch only makes the minimal fix to both
ext4 and f2fs.  It leaves ubifs as-is, since ubifs doesn't compare the
ciphertext block yet.  Follow-on patches will clean things up properly
and make the filesystems use a shared helper function.

Fixes: 5de0b4d0cd ("ext4 crypto: simplify and speed up filename encryption")
Reported-by: Gwendal Grignou <gwendal@chromium.org>
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-04 11:44:36 -04:00
Jaegeuk Kim
6332cd32c8 f2fs: check entire encrypted bigname when finding a dentry
If user has no key under an encrypted dir, fscrypt gives digested dentries.
Previously, when looking up a dentry, f2fs only checks its hash value with
first 4 bytes of the digested dentry, which didn't handle hash collisions fully.
This patch enhances to check entire dentry bytes likewise ext4.

Eric reported how to reproduce this issue by:

 # seq -f "edir/abcdefghijklmnopqrstuvwxyz012345%.0f" 100000 | xargs touch
 # find edir -type f | xargs stat -c %i | sort | uniq | wc -l
100000
 # sync
 # echo 3 > /proc/sys/vm/drop_caches
 # keyctl new_session
 # find edir -type f | xargs stat -c %i | sort | uniq | wc -l
99999

Cc: <stable@vger.kernel.org>
Reported-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
(fixed f2fs_dentry_hash() to work even when the hash is 0)
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-04 11:44:35 -04:00
Sheng Yong
d3bb910c15 f2fs: fix multiple f2fs_add_link() having same name for inline dentry
Commit 88c5c13a50 (f2fs: fix multiple f2fs_add_link() calls having
same name) does not cover the scenario where inline dentry is enabled.
In that case, F2FS_I(dir)->task will be NULL, and __f2fs_add_link will
lookup dentries one more time.

This patch fixes it by moving the assigment of current task to a upper
level to cover both normal and inline dentry.

Cc: <stable@vger.kernel.org>
Fixes: 88c5c13a50 (f2fs: fix multiple f2fs_add_link() calls having same name)
Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-25 14:16:31 -07:00
Tomohiro Kusumi
64c24ecb3c f2fs: split make_dentry_ptr() into block and inline versions
Since callers statically know which type to use, make_dentry_ptr()
can simply be splitted into two inline functions. This way, the code
has less inlined, fewer arguments, and no cast.

Signed-off-by: Tomohiro Kusumi <tkusumi@tuxera.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-05 11:05:08 -07:00
Kinglong Mee
d03ba4cc3f f2fs: cleanup the disk level filename updating
As discuss with Jaegeuk and Chao,
"Once checkpoint is done, f2fs doesn't need to update there-in filename at all."

The disk-level filename is used only one case,
1. create a file A under a dir
2. sync A
3. godown
4. umount
5. mount (roll_forward)

Only the rename/cross_rename changes the filename, if it happens,
a. between step 1 and 2, the sync A will caused checkpoint, so that,
   the roll_forward at step 5 never happens.
b. after step 2, the roll_forward happens, file A will roll forward
   to the result as after step 1.

So that, any updating the disk filename is useless, just cleanup it.

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-03-21 22:34:33 -04:00
Jaegeuk Kim
23380b8568 f2fs: use __set{__clear}_bit_le
This patch uses __set{__clear}_bit_le for highter speed.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-03-20 10:00:16 -04:00
Linus Torvalds
25c4e6c3f0 for-f2fs-4.11
This round introduces several interesting features such as on-disk NAT bitmaps,
 IO alignment, and a discard thread. And it includes a couple of major bug fixes
 as below.
 
 == Enhancement ==
 - introduce on-disk bitmaps to avoid scanning NAT blocks when getting free nids
 - support IO alignment to prepare open-channel SSD integration in future
 - introduce a discard thread to avoid long latency during checkpoint and fstrim
 - use SSR for warm node and enable inline_xattr by default
 - introduce in-memory bitmaps to check FS consistency for debugging
 - improve write_begin by avoiding needless read IO
 
 == Bug fix ==
 - fix broken zone_reset behavior for SMR drive
 - fix wrong victim selection policy during GC
 - fix missing behavior when preparing discard commands
 - fix bugs in atomic write support and fiemap
 - workaround to handle multiple f2fs_add_link calls having same name
 
 And it includes a bunch of clean-up patches as well.
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Merge tag 'for-f2fs-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

Pull f2fs updates from Jaegeuk Kim:
 "This round introduces several interesting features such as on-disk NAT
  bitmaps, IO alignment, and a discard thread. And it includes a couple
  of major bug fixes as below.

  Enhancements:

   - introduce on-disk bitmaps to avoid scanning NAT blocks when getting
     free nids

   - support IO alignment to prepare open-channel SSD integration in
     future

   - introduce a discard thread to avoid long latency during checkpoint
     and fstrim

   - use SSR for warm node and enable inline_xattr by default

   - introduce in-memory bitmaps to check FS consistency for debugging

   - improve write_begin by avoiding needless read IO

  Bug fixes:

   - fix broken zone_reset behavior for SMR drive

   - fix wrong victim selection policy during GC

   - fix missing behavior when preparing discard commands

   - fix bugs in atomic write support and fiemap

   - workaround to handle multiple f2fs_add_link calls having same name

  ... and it includes a bunch of clean-up patches as well"

* tag 'for-f2fs-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (97 commits)
  f2fs: avoid to flush nat journal entries
  f2fs: avoid to issue redundant discard commands
  f2fs: fix a plint compile warning
  f2fs: add f2fs_drop_inode tracepoint
  f2fs: Fix zoned block device support
  f2fs: remove redundant set_page_dirty()
  f2fs: fix to enlarge size of write_io_dummy mempool
  f2fs: fix memory leak of write_io_dummy mempool during umount
  f2fs: fix to update F2FS_{CP_}WB_DATA count correctly
  f2fs: use MAX_FREE_NIDS for the free nids target
  f2fs: introduce free nid bitmap
  f2fs: new helper cur_cp_crc() getting crc in f2fs_checkpoint
  f2fs: update the comment of default nr_pages to skipping
  f2fs: drop the duplicate pval in f2fs_getxattr
  f2fs: Don't update the xattr data that same as the exist
  f2fs: kill __is_extent_same
  f2fs: avoid bggc->fggc when enough free segments are avaliable after cp
  f2fs: select target segment with closer temperature in SSR mode
  f2fs: show simple call stack in fault injection message
  f2fs: no need lock_op in f2fs_write_inline_data
  ...
2017-03-01 15:55:04 -08:00
Chao Yu
55523519bc f2fs: show simple call stack in fault injection message
Previously kernel message can show that in which function we do the
injection, but unfortunately, most of the caller are the same, for
tracking more information of injection path, it needs to show upper
caller's name. This patch supports that ability.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 09:59:55 -08:00
Jaegeuk Kim
88c5c13a50 f2fs: fix multiple f2fs_add_link() calls having same name
It turns out a stakable filesystem like sdcardfs in AOSP can trigger multiple
vfs_create() to lower filesystem. In that case, f2fs will add multiple dentries
having same name which breaks filesystem consistency.

Until upper layer fixes, let's work around by f2fs, which shows actually not
much performance regression.

Cc: <stable@vger.kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-23 11:23:25 -08:00
Eric Biggers
54475f531b fscrypt: use ENOKEY when file cannot be created w/o key
As part of an effort to clean up fscrypt-related error codes, make
attempting to create a file in an encrypted directory that hasn't been
"unlocked" fail with ENOKEY.  Previously, several error codes were used
for this case, including ENOENT, EACCES, and EPERM, and they were not
consistent between and within filesystems.  ENOKEY is a better choice
because it expresses that the failure is due to lacking the encryption
key.  It also matches the error code returned when trying to open an
encrypted regular file without the key.

I am not aware of any users who might be relying on the previous
inconsistent error codes, which were never documented anywhere.

This failure case will be exercised by an xfstest.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-12-31 16:26:20 -05:00
Chao Yu
ed6bd4b146 f2fs: report error of f2fs_fill_dentries
Report error of f2fs_fill_dentries to ->iterate_shared, otherwise when
error ocurrs, user may just list part of dirents in target directory
without any hints.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-11-23 12:11:12 -08:00