Commit Graph

330 Commits

Author SHA1 Message Date
Jaegeuk Kim
399368372e f2fs: introduce a new global lock scheme
In the previous version, f2fs uses global locks according to the usage types,
such as directory operations, block allocation, block write, and so on.

Reference the following lock types in f2fs.h.
enum lock_type {
	RENAME,		/* for renaming operations */
	DENTRY_OPS,	/* for directory operations */
	DATA_WRITE,	/* for data write */
	DATA_NEW,	/* for data allocation */
	DATA_TRUNC,	/* for data truncate */
	NODE_NEW,	/* for node allocation */
	NODE_TRUNC,	/* for node truncate */
	NODE_WRITE,	/* for node write */
	NR_LOCK_TYPE,
};

In that case, we lose the performance under the multi-threading environment,
since every types of operations must be conducted one at a time.

In order to address the problem, let's share the locks globally with a mutex
array regardless of any types.
So, let users grab a mutex and perform their jobs in parallel as much as
possbile.

For this, I propose a new global lock scheme as follows.

0. Data structure
 - f2fs_sb_info -> mutex_lock[NR_GLOBAL_LOCKS]
 - f2fs_sb_info -> node_write

1. mutex_lock_op(sbi)
 - try to get an avaiable lock from the array.
 - returns the index of the gottern lock variable.

2. mutex_unlock_op(sbi, index of the lock)
 - unlock the given index of the lock.

3. mutex_lock_all(sbi)
 - grab all the locks in the array before the checkpoint.

4. mutex_unlock_all(sbi)
 - release all the locks in the array after checkpoint.

5. block_operations()
 - call mutex_lock_all()
 - sync_dirty_dir_inodes()
 - grab node_write
 - sync_node_pages()

Note that,
 the pairs of mutex_lock_op()/mutex_unlock_op() and
 mutex_lock_all()/mutex_unlock_all() should be used together.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-09 18:21:18 +09:00
Jaegeuk Kim
b74737541c f2fs: avoid race for summary information
In order to do GC more reliably, I'd like to lock the vicitm summary page
until its GC is completed, and also prevent any checkpoint process.

Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-03 17:27:51 +09:00
Jaegeuk Kim
5ec4e49f9b f2fs: change GC bitmaps to apply the section granularity
This patch removes a bitmap for victim segments selected by foreground GC, and
modifies the other bitmap for victim segments selected by background GC.

1) foreground GC bitmap
 : We don't need to manage this, since we just only one previous victim section
   number instead of the whole victim history.
   The f2fs uses the victim section number in order not to allocate currently
   GC'ed section to current active logs.

2) background GC bitmap
 : This bitmap is used to avoid selecting victims repeatedly by background GCs.
   In addition, the victims are able to be selected by foreground GCs, since
   there is no need to read victim blocks during foreground GCs.

   By the fact that the foreground GC reclaims segments in a section unit, it'd
   be better to manage this bitmap based on the section granularity.

Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-03 17:27:49 +09:00
Jaegeuk Kim
6ead114232 f2fs: fix the recovery flow to handle errors correctly
We should handle errors during the recovery flow correctly.
For example, if we get -ENOMEM, we should report a mount failure instead of
conducting the remained mount procedure.

Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-03-27 09:16:06 +09:00
Masanari Iida
111d2495a8 f2fs: fix typo in comments
Correct spelling typo in comments

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-03-20 18:30:16 +09:00
Namjae Jeon
c0d39e65ba f2fs: fix return values from validate superblock
validate super block is not returning with proper values.
When failure from sb_bread it should reflect there is an EIO otherwise
it should return of EINVAL.
Returning, '1' is not conveying proper message as the return type.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-03-20 18:30:15 +09:00
Namjae Jeon
d3ee456dfb f2fs: notify when discard is not supported
Change f2fs so that a warning is emitted when an attempt is made to
mount a filesystem with the unsupported discard option.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-03-20 18:30:14 +09:00
Masanari Iida
434720fa98 f2fs: Fix typo in comments
Correct spelling typo in comments

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-03-19 09:44:55 +01:00
Jaegeuk Kim
5a20d339c7 f2fs: align f2fs maximum name length to linux based filesystem
The maximum filename length supported in linux is 255 characters.
So let's follow that.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-03-18 21:00:35 +09:00
Eric W. Biederman
7f78e03513 fs: Limit sys_mount to only request filesystem modules.
Modify the request_module to prefix the file system type with "fs-"
and add aliases to all of the filesystems that can be built as modules
to match.

A common practice is to build all of the kernel code and leave code
that is not commonly needed as modules, with the result that many
users are exposed to any bug anywhere in the kernel.

Looking for filesystems with a fs- prefix limits the pool of possible
modules that can be loaded by mount to just filesystems trivially
making things safer with no real cost.

Using aliases means user space can control the policy of which
filesystem modules are auto-loaded by editing /etc/modprobe.d/*.conf
with blacklist and alias directives.  Allowing simple, safe,
well understood work-arounds to known problematic software.

This also addresses a rare but unfortunate problem where the filesystem
name is not the same as it's module name and module auto-loading
would not work.  While writing this patch I saw a handful of such
cases.  The most significant being autofs that lives in the module
autofs4.

This is relevant to user namespaces because we can reach the request
module in get_fs_type() without having any special permissions, and
people get uncomfortable when a user specified string (in this case
the filesystem type) goes all of the way to request_module.

After having looked at this issue I don't think there is any
particular reason to perform any filtering or permission checks beyond
making it clear in the module request that we want a filesystem
module.  The common pattern in the kernel is to call request_module()
without regards to the users permissions.  In general all a filesystem
module does once loaded is call register_filesystem() and go to sleep.
Which means there is not much attack surface exposed by loading a
filesytem module unless the filesystem is mounted.  In a user
namespace filesystems are not mounted unless .fs_flags = FS_USERNS_MOUNT,
which most filesystems do not set today.

Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Acked-by: Kees Cook <keescook@chromium.org>
Reported-by: Kees Cook <keescook@google.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-03-03 19:36:31 -08:00
Jaegeuk Kim
437275272f f2fs: clarify and enhance the f2fs_gc flow
This patch makes clearer the ambiguous f2fs_gc flow as follows.

1. Remove intermediate checkpoint condition during f2fs_gc
 (i.e., should_do_checkpoint() and GC_BLOCKED)

2. Remove unnecessary return values of f2fs_gc because of #1.
 (i.e., GC_NODE, GC_OK, etc)

3. Simplify write_checkpoint() because of #2.

4. Clarify the main f2fs_gc flow.
 o monitor how many freed sections during one iteration of do_garbage_collect().
 o do GC more without checkpoints if we can't get enough free sections.
 o do checkpoint once we've got enough free sections through forground GCs.

5. Adopt thread-logging (Slack-Space-Recycle) scheme more aggressively on data
  log types. See. get_ssr_segement()

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-02-12 07:15:02 +09:00
majianpeng
14d7e9de05 f2fs: when check superblock failed, try to check another superblock
In f2fs, there are two superblocks. So when the first superblock was
invalidate, it should try to check another.

By Jaegeuk Kim:
 o Remove a white space for coding style
 o Clean up for code readability
 o Fix a typo

Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-02-12 07:15:01 +09:00
majianpeng
5c9b469295 f2fs: use F2FS_BLKSIZE to judge bloksize and page_cache_size
In some system PAGE_CACHE_SIZE isn't 4K. So using F2FS_BLKSIZE to judge.

By Jaegeuk Kim:
 o f2fs does not support no other 4KB page cache size.

Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-02-12 07:15:01 +09:00
Changman Lee
d6212a5f18 f2fs: add un/freeze_fs into super_operations
This patch supports ioctl FIFREEZE and FITHAW to snapshot filesystem.
Before calling f2fs_freeze, all writers would be suspended and sync_fs
would be completed. So no f2fs has to do something.
Just background gc operation should be skipped due to generate dirty
nodes and data until unfreeze.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-02-12 07:15:00 +09:00
Alejandro Martinez Ruiz
aa43507f68 f2fs: fix disable_ext_identify option spelling
There is a typo in the ->show_options function for disable_ext_identify.
Fix it to match the spelling from the documentation.

Signed-off-by: Alejandro Martinez Ruiz <alex@nowcomputing.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-02-12 07:15:00 +09:00
Jaegeuk Kim
577e349514 f2fs: prevent checkpoint once any IO failure is detected
This patch enhances the checkpoint routine to cope with IO errors.

Basically f2fs detects IO errors from end_io_write, and the errors are able to
be occurred during one of data, node, and meta page writes.

In the previous code, when an IO error is occurred during writes, f2fs sets a
flag, CP_ERROR_FLAG, in the raw ckeckpoint buffer which will be written to disk.
Afterwards, write_checkpoint() will check the flag and remount f2fs as a
read-only (ro) mode.

However, even once f2fs is remounted as a ro mode, dirty checkpoint pages are
freely able to be written to disk by flusher or kswapd in background.
In such a case, after cold reboot, f2fs would restore the checkpoint data having
CP_ERROR_FLAG, resulting in disabling write_checkpoint and remounting f2fs as
a ro mode again.

Therefore, let's prevent any checkpoint page (meta) writes once an IO error is
occurred, and remount f2fs as a ro mode right away at that moment.

Reported-by: Oliver Winker <oliver@oli1170.net>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
2013-02-12 07:15:00 +09:00
Namjae Jeon
6e6093a8f1 f2fs: add __init to functions in init_f2fs_fs
Add __init to functions in init_f2fs_fs for code consistency.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-01-22 10:48:38 +09:00
Namjae Jeon
4589d25d01 f2fs: fix the debugfs entry creation path
As the "status" debugfs entry will be maintained for entire F2FS filesystem
irrespective of the number of partitions.
So, we can move the initialization to the init part of the f2fs and destroy will
be done from exit part. After making changes, for individual partition mount -
entry creation code will not be executed.

Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-01-15 20:19:15 +09:00
Namjae Jeon
ff9234ad4e f2fs: remove redundant call to set_blocksize in f2fs_fill_super
Since, f2fs supports only 4KB blocksize, which is set at the beginning in
f2fs_fill_super. So, we do not need to again check this blocksize setting
in such case.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-01-14 09:41:30 +09:00
Jaegeuk Kim
7d82db8316 f2fs: add f2fs_balance_fs in several interfaces
The f2fs_balance_fs() is to check the number of free sections and decide whether
it needs to conduct cleaning or not. If there are not enough free sections, the
cleaning job should be started.

In order to control an amount of free sections even under high utilization, f2fs
should call f2fs_balance_fs at all the VFS interfaces that are able to produce
dirty pages.
This patch adds the function calls in the missing interfaces as follows.

1. f2fs_setxattr()
The f2fs_setxattr() produces dirty node pages so that we should call
f2fs_balance_fs() either likewise doing in other VFS interfaces such as
f2fs_lookup(), f2fs_mkdir(), and so on.

2. f2fs_sync_file()
We should guarantee serving free sections for syncing metadata during fsync.
Previously, there is no space check before triggering checkpoint and
sync_node_pages.
Therefore, if a bunch of fsync calls are triggered under 100% of FS utilization,
f2fs is able to be faced with no free sections, resulting in BUG_ON().

3. f2fs_sync_fs()
Before calling write_checkpoint(), we should guarantee that there are minimum
free sections.

4. f2fs_write_inode()
f2fs_write_inode() is also able to produce dirty node pages.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-01-11 15:09:17 +09:00
Namjae Jeon
a07ef78435 f2fs: introduce f2fs_msg to ease adding information prints
Introduced f2fs_msg function to differentiate f2fs specific messages in
the log. And, added few informative prints in the mount path, to convey
proper error in case of mount failure.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-01-04 09:42:59 +09:00
Namjae Jeon
64c576fe51 f2fs: remove unneeded variable from f2fs_sync_fs
We can directly return '0' from the function, instead of introducing a
'ret' variable.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-12-28 11:27:45 +09:00
Jaegeuk Kim
12a67146e3 f2fs: return a default value for non-void function
This patch resolves a build warning reported by kbuild test robot.

"
fs/f2fs/segment.c: In function '__get_segment_type':
fs/f2fs/segment.c:806:1: warning: control reaches end of non-void
function [-Wreturn-type]
"

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-12-28 11:24:09 +09:00
Jaegeuk Kim
30f0c75858 f2fs: should recover orphan and fsync data
The recovery routine should do all the time regardless of normal umount action.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-12-26 10:39:52 +09:00
Jaegeuk Kim
1362b5e347 f2fs: fix wrong calculation on f_files in statfs
In f2fs_statfs(), f_files should be the total number of available inodes
instead of the currently allocated inodes.
So, this patch should resolve the reported bug below.

Note that, showing 10% usage is not a bug, since f2fs reveals whole volume size
as much as possible and shows the space overhead as *used*.
This policy is fair enough with respect to other file systems.

<Reported Bug>
(loop0 is backed by 1GiB file)

$ mkfs.f2fs /dev/loop0

F2FS-tools: Ver: 1.1.0 (2012-12-11)
Info: sector size = 512
Info: total sectors = 2097152 (in 512bytes)
Info: zone aligned segment0 blkaddr: 512
Info: format successful

$ mount /dev/loop0 mnt/

$ df mnt/
Filesystem     1K-blocks  Used Available Use% Mounted on
/dev/loop0       1046528 98312    929784  10%
/home/zeta/linux-devel/mtd-bench/mnt

$ df mnt/ -i
Filesystem     Inodes   IUsed  IFree IUse% Mounted on
/dev/loop0       1 -465918 465919     - /home/zeta/linux-devel/mtd-bench/mnt

Notice IUsed is negative. Also, 10% usage on a fresh f2fs seems too
much to be correct.

Reported-and-Tested-by: Ezequiel Garcia <elezegarcia@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-12-26 10:39:51 +09:00
Namjae Jeon
154a086529 f2fs: remove unneeded memset from init_once
Since, __GFP_ZERO is used while f2fs inode allocation, so we do not
need memset for f2fs_inode_info, as this is already zeroed out.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
2012-12-11 13:43:43 +09:00
Namjae Jeon
72ce6094c0 f2fs: show error in case of invalid mount arguments
print the invalid argument/value from parse_options in case of
mount failure.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
2012-12-11 13:43:43 +09:00
Jaegeuk Kim
0a8165d7c2 f2fs: adjust kernel coding style
As pointed out by Randy Dunlap, this patch removes all usage of "/**" for comment
blocks. Instead, just use "/*".

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-12-11 13:43:42 +09:00
Jaegeuk Kim
25ca923b2a f2fs: fix endian conversion bugs reported by sparse
This patch should resolve the bugs reported by the sparse tool.
Initial reports were written by "kbuild test robot" managed by fengguang.wu.

In my local machines, I've tested also by running:
> make C=2 CF="-D__CHECK_ENDIAN__"

Accordingly, I've found lots of warnings and bugs related to the endian
conversion. And I've fixed all at this moment.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-12-11 13:43:42 +09:00
Jaegeuk Kim
aff063e266 f2fs: add super block operations
This adds the implementation of superblock operations for f2fs, which includes
- init_f2fs_fs/exit_f2fs_fs
- f2fs_mount
- super_operations of f2fs

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-12-11 13:43:40 +09:00