Commit Graph

176 Commits

Author SHA1 Message Date
Jaegeuk Kim 93dfe2ac51 f2fs: refactor bio-related operations
This patch integrates redundant bio operations on read and write IOs.

1. Move bio-related codes to the top of data.c.
2. Replace f2fs_submit_bio with f2fs_submit_merged_bio, which handles read
   bios additionally.
3. Introduce __submit_merged_bio to submit the merged bio.
4. Change f2fs_readpage to f2fs_submit_page_bio.
5. Introduce f2fs_submit_page_mbio to integrate previous submit_read_page and
   submit_write_page.

Reviewed-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Reviewed-by: Chao Yu <chao2.yu@samsung.com >
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-12-23 10:18:05 +09:00
Chao Yu 01d2d1aa06 f2fs: use true and false for boolean variable
The inode_page_locked should be a boolean variable.

struct dnode_of_data {
	struct inode *inode;            /* vfs inode pointer */
	struct page *inode_page;        /* its inode page, NULL is possible */
	struct page *node_page;         /* cached direct node page */
	nid_t nid;                      /* node id of the direct node block */
	unsigned int ofs_in_node;       /* data offset in the node page */
==>	bool inode_page_locked;         /* inode page is locked or not */
	block_t data_blkaddr;           /* block address of the node block */
};

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
[Jaegeuk Kim: add description]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-12-23 10:18:04 +09:00
Changman Lee 03232305ff f2fs: send REQ_META or REQ_PRIO when reading meta area
Let's send REQ_META or REQ_PRIO when reading meta area such as NAT/SIT
etc.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-12-23 10:18:03 +09:00
Jaegeuk Kim 7107e0a9b1 f2fs: merge read IOs at ra_nat_pages()
Change log from v1:
  o add mark_page_accessed() not to reclaim the nat pages.

This patch changes the policy of submitting read bios at ra_nat_pages.

Previously, f2fs submits small read bios with block plugging.
But, with this patch, f2fs itself merges read bios first and then submits a
large bio, which can reduce the bio handling overheads.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-12-23 10:18:02 +09:00
Gu Zheng ef86d70994 f2fs: convert inc/dec_valid_node_count to inc/dec one count
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-12-23 10:18:01 +09:00
Gu Zheng 58e674d6ab f2fs: convert remove_inode_page to void
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-12-23 10:18:01 +09:00
Chao Yu 4bf08ff6f9 f2fs: remove unnecessary TestClearPageError when wait pages writeback
In wait_on_node_pages_writeback we will test and clear error flag for all
pages in radix tree, but not necessary.
So we only do this for pages belong to the specified inode.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-11-04 12:24:01 +09:00
Jaegeuk Kim cfe58f9dcd f2fs: avoid to wait all the node blocks during fsync
Previously, f2fs_sync_file() waits for all the node blocks to be written.
But, we don't need to do that, but wait only the inode-related node blocks.

This patch adds wait_on_node_pages_writeback() in which waits inode-related
node blocks that are on writeback.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-31 16:01:03 +09:00
Jaegeuk Kim 5d56b6718a f2fs: add an option to avoid unnecessary BUG_ONs
If you want to remove unnecessary BUG_ONs, you can just turn off F2FS_CHECK_FS
in your kernel config.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-29 15:44:38 +09:00
Jaegeuk Kim 26c6b88799 f2fs: add tracepoint for set_page_dirty
This patch adds a tracepoint for set_page_dirty.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-25 16:54:40 +09:00
Jaegeuk Kim 4660f9c0fe f2fs: introduce f2fs_balance_fs_bg for some background jobs
This patch merges some background jobs into this new function.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-25 16:54:38 +09:00
Jaegeuk Kim 81eb8d6e28 f2fs: reclaim prefree segments periodically
Previously, f2fs postpones reclaiming prefree segments into free segments
as much as possible.
However, if user writes and deletes a bunch of data without any sync or fsync
calls, some flash storages can suffer from garbage collections.

So, this patch adds the reclaiming codes to f2fs_write_node_pages and background
GC thread.

If there are a lot of prefree segments, let's do checkpoint so that f2fs
submits discard commands for the prefree regions to the flash storage.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-25 16:54:37 +09:00
Haicheng Li aabe51364f f2fs: use bool for booleans
Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-25 16:54:37 +09:00
Gu Zheng 7bd59381c8 f2fs: introduce f2fs_kmem_cache_alloc to hide the unfailed, kmem cache allocation
Introduce the unfailed version of kmem_cache_alloc named f2fs_kmem_cache_alloc
to hide the retry routine and make the code a bit cleaner.

v2:
   Fix the wrong use of 'retry' tag pointed out by Gao feng.
   Use more neat code to remove redundant tag suggested by Haicheng Li.

Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-22 20:16:02 +09:00
Jaegeuk Kim 87a9bd2656 f2fs: avoid to write during the recovery
This patch enhances the recovery routine not to write any data/node/meta until
its completion.
If any writes are sent to the disk, it could contaminate the written history
that will be used for further recovery.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-18 09:44:14 +09:00
Jaegeuk Kim 423e95ccbe f2fs: merge more bios of node block writes
Previously, we experience bio traces as follows when running simple sequential
write test.

 f2fs_do_submit_bio: type = NODE, io = no sync, sector = 500104928, size = 4K
 f2fs_do_submit_bio: type = NODE, io = no sync, sector = 499922208, size = 368K
 f2fs_do_submit_bio: type = NODE, io = no sync, sector = 499914752, size = 140K

 -> total 512K

The first one is to write an indirect node block, and the others are to write
direct node blocks.

The reason why there are two separate bios for direct node blocks is:
0. initial state
------------------    ------------------
|                |    |xxxxxxxx        |
------------------    ------------------

1. write 368K
------------------    ------------------
|                |    |xxxxxxxxWWWWWWWW|
------------------    ------------------

2. write 140K
------------------    ------------------
|WWWWWWW         |    |xxxxxxxxWWWWWWWW|
------------------    ------------------

This is because f2fs_write_node_pages tries to write just 512K totally, so that
we can lose the chance to merge more bios nicely.

After this patch is applied, we can get the following bio traces.

  f2fs_do_submit_bio: type = NODE, io = no sync, sector = 500103168, size = 8K
  f2fs_do_submit_bio: type = NODE, io = no sync, sector = 500111368, size = 4K
  f2fs_do_submit_bio: type = NODE, io = no sync, sector = 500107272, size = 512K
  f2fs_do_submit_bio: type = NODE, io = no sync, sector = 500108296, size = 512K
  f2fs_do_submit_bio: type = NODE, io = no sync, sector = 500109320, size = 500K

And finally, we can improve the sequential write performance,
    from 458.775 MB/s to 479.945 MB/s on SSD.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-09-05 10:17:19 +09:00
Jaegeuk Kim 65985d935d f2fs: support the inline xattrs
0. modified inode structure
--------------------------------------
metadata (e.g., i_mtime, i_ctime, etc)
--------------------------------------
direct pointers [0 ~ 873]

inline xattrs (200 bytes by default)

indirect pointers [0 ~ 4]
--------------------------------------
node footer
--------------------------------------

1. setxattr flow
 - read_all_xattrs copies all the xattrs from inline and xattr node block.
 - handle xattr entries
 - write_all_xattrs copies modified xattrs into inline and xattr node block.

2. getxattr flow
 - read_all_xattrs copies all the xattrs from inline and xattr node block.
 - check target entries

3. Usage
 # mount -t f2fs -o inline_xattr $DEV $MNT

 Once mounted with the inline_xattr option, f2fs marks all the newly created
 files to reserve an amount of inline xattr space explicitly inside the inode
 block. Without the mount option, f2fs will not touch any existing files and
 newly created files as well.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-08-26 20:15:23 +09:00
Jaegeuk Kim 4f16fb0f9b f2fs: add the truncate_xattr_node function
The truncate_xattr_node function will be used by inline xattr.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-08-26 20:15:06 +09:00
Jaegeuk Kim de93653fe3 f2fs: reserve the xattr space dynamically
This patch enables the number of direct pointers inside on-disk inode block to
be changed dynamically according to the size of inline xattr space.

The number of direct pointers, ADDRS_PER_INODE, can be changed only if the file
has inline xattr flag.

The number of direct pointers that will be used by inline xattrs is defined as
F2FS_INLINE_XATTR_ADDRS.
Current patch assigns F2FS_INLINE_XATTR_ADDRS to 0 temporarily.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-08-26 20:15:01 +09:00
Dan Carpenter e27dae4d66 f2fs: alloc_page() doesn't return an ERR_PTR
alloc_page() returns a NULL on failure, it never returns an ERR_PTR.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-08-19 09:42:29 +09:00
Jaegeuk Kim 479bd73ac4 f2fs: should cover i_xattr_nid with its xattr node page lock
Previously, f2fs_setxattr assigns i_xattr_nid in the inode page inconsistently.

The scenario is:

= Thread 1 =         = Thread 2 =     = fi->i_xattr_nid =  = on-disk nid =

f2fs_setxattr                                   0                 0
  new_node_page                                 X                 0
                   sync_inode_page              X                 X
                   checkpoint                   X                 X -.
    grab_cache_page                             X                 X  |
--> allocate a new xattr node block or -ENOSPC      <----------------'

At this moment, the checkpoint stores inconsistent data where the inode has
i_xattr_nid but actual xattr node block is not allocated yet.

So, we should assign the real i_xattr_nid only after its xattr node block is
allocated.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-08-12 16:04:53 +09:00
Jaegeuk Kim 9c02740c01 f2fs: check the free space first in new_node_page
Let's check the free space in prior to the main process of allocating a new node
page.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-08-12 16:00:46 +09:00
Gu Zheng 41dfde135f f2fs: clean up the needless end 'return' of void function
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-08-12 11:49:22 +09:00
Gu Zheng 4559071063 f2fs: introduce help function F2FS_NODE()
Introduce help function F2FS_NODE() to simplify the conversion of node_page to
f2fs_node.

Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-07-30 15:17:02 +09:00
Linus Torvalds 3f490f7f99 This patch-set includes the following major enhancement patches.
o remount_fs callback function
  o restore parent inode number to enhance the fsync performance
  o xattr security labels
  o reduce the number of redundant lock/unlock data pages
  o avoid frequent write_inode calls
 
 The other minor bug fixes are as follows.
  o endian conversion bugs
  o various bugs in the roll-forward recovery routine
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.11 (GNU/Linux)
 
 iQIcBAABAgAGBQJR0h8YAAoJEEAUqH6CSFDSJNMP/1V+e/PaLa8YsHuw5eWPT3Fe
 RYFXJv7SXadHqgQInjwD7JOF8BC9DlUyknYUiXFUZgvKsgMHz+OTCNl+1hLTbUXt
 e6Rhn7vU/fMu3TEtj+v6g8JbpXdXH8TSbtvh9LpoczRS98GYpZuckP0BtQsVkTL3
 jIq6WD8JRkb2DvpDl7viTT0Eq0T61CSmtOwOIvfhhiVxggvDWcnR1mTM9Tymdi4J
 NKtFkjCsKP0Z/7IZZUJAczGEHjsT+O6JDwp8+KVWuZT4BSuchoX4MYAY5wX527Ne
 rZvkolbbfnAFCC3BtETr0DPOkpxnHmJ6dEveIxjZ9cux12CAFA/Ww1QAL4ygiDkd
 Avn8BBEJnfnuzeOUkE0by+9hdF9LOU3CVSxiDhWJegYB16z+c9pSBD9xvlKhKk5B
 QNsjptB6m0CftAq7vIDsryL60uJ2cSHFxPqfwAHEpNngiU/NohTFSZE0sUMbLUNh
 FI6NrHoT7yld1HcB6cvL1lnUqIENFbNhDSSDcTdlN49IJJap4oqtgCnmMMIwbUCO
 vR2/26k5W7NwG+K6XN2IX13AsayzQahxTv8in/+LV0bfjHo6/1VzzGcqAmXJbDQw
 dLrNAeWaaIJi8J/zJiENMbFKXTj8Wax9jxKsW+4towQuyEt4ADvyt1c5gX3VR42T
 x8+YEargsdBf6FAhtN+H
 =qFcy
 -----END PGP SIGNATURE-----

Merge tag 'for-f2fs-3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

Pull f2fs updates from Jaegeuk Kim:
 "This patch-set includes the following major enhancement patches:
   - remount_fs callback function
   - restore parent inode number to enhance the fsync performance
   - xattr security labels
   - reduce the number of redundant lock/unlock data pages
   - avoid frequent write_inode calls

  The other minor bug fixes are as follows.
   - endian conversion bugs
   - various bugs in the roll-forward recovery routine"

* tag 'for-f2fs-3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (56 commits)
  f2fs: fix to recover i_size from roll-forward
  f2fs: remove the unused argument "sbi" of func destroy_fsync_dnodes()
  f2fs: remove reusing any prefree segments
  f2fs: code cleanup and simplify in func {find/add}_gc_inode
  f2fs: optimize the init_dirty_segmap function
  f2fs: fix an endian conversion bug detected by sparse
  f2fs: fix crc endian conversion
  f2fs: add remount_fs callback support
  f2fs: recover wrong pino after checkpoint during fsync
  f2fs: optimize do_write_data_page()
  f2fs: make locate_dirty_segment() as static
  f2fs: remove unnecessary parameter "offset" from __add_sum_entry()
  f2fs: avoid freqeunt write_inode calls
  f2fs: optimise the truncate_data_blocks_range() range
  f2fs: use the F2FS specific flags in f2fs_ioctl()
  f2fs: sync dir->i_size with its block allocation
  f2fs: fix i_blocks translation on various types of files
  f2fs: set sb->s_fs_info before calling parse_options()
  f2fs: support xattr security labels
  f2fs: fix iget/iput of dir during recovery
  ...
2013-07-02 09:42:38 -07:00
Jaegeuk Kim 8ae8f1627f f2fs: support xattr security labels
This patch adds the support of security labels for f2fs, which will be used
by Linus Security Models (LSMs).

Quote from http://en.wikipedia.org/wiki/Linux_Security_Modules:
"Linux Security Modules (LSM) is a framework that allows the Linux kernel to
support a variety of computer security models while avoiding favoritism toward
any single security implementation. The framework is licensed under the terms of
the GNU General Public License and is standard part of the Linux kernel since
Linux 2.6. AppArmor, SELinux, Smack and TOMOYO Linux are the currently accepted
modules in the official kernel.".

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-06-11 16:01:03 +09:00
Jaegeuk Kim f356fe0cba f2fs: add debug msgs in the recovery routine
This patch adds some trivial debugging messages in the recovery process.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-05-28 15:03:02 +09:00
Jaegeuk Kim 44a83ff6a8 f2fs: update inode page after creation
I found a bug when testing power-off-recovery as follows.

[Bug Scenario]
1. create a file
2. fsync the file
3. reboot w/o any sync
4. try to recover the file
 - found its fsync mark
 - found its dentry mark
   : try to recover its dentry
    - get its file name
    - get its parent inode number
     : here we got zero value

The reason why we get the wrong parent inode number is that we didn't
synchronize the inode page with its newly created inode information perfectly.

Especially, previous f2fs stores fi->i_pino and writes it to the cached
node page in a wrong order, which incurs the zero-valued i_pino during the
recovery.

So, this patch modifies the creation flow to fix the synchronization order of
inode page with its inode.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-05-28 15:03:02 +09:00
Jaegeuk Kim 1646cfac95 f2fs: skip get_node_page if locked node page is passed
If get_dnode_of_data gets a locked node page, let's skip redundant
get_node_page calls.
This is for the futher enhancement.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-05-28 15:03:01 +09:00
Jaegeuk Kim 65e5cd0a15 f2fs: fix inconsistency of block count during recovery
Currently f2fs recovers the dentry of fsynced files.
When power-off-recovery is conducted, this newly recovered inode should increase
node block count as well as inode block count.

This patch resolves this inconsistency that results in:

1. create a file
2. write data
3. fsync
4. reboot without sync
5. mount and recover the file
6. node block count is 1 and inode block count is 2
 : fall into the inconsistent state
7. unlink the file
 : trigger the following BUG_ON

------------[ cut here ]------------
kernel BUG at /home/zeus/f2fs_test/src/fs/f2fs/f2fs.h:716!
Call Trace:
 [<ffffffffa0344100>] ? get_node_page+0x50/0x1a0 [f2fs]
 [<ffffffffa0344bfc>] remove_inode_page+0x8c/0x100 [f2fs]
 [<ffffffffa03380f0>] ? f2fs_evict_inode+0x180/0x2d0 [f2fs]
 [<ffffffffa033812e>] f2fs_evict_inode+0x1be/0x2d0 [f2fs]
 [<ffffffff811c7a67>] evict+0xa7/0x1a0
 [<ffffffff811c82b5>] iput+0x105/0x190
 [<ffffffff811c2b30>] d_kill+0xe0/0x120
 [<ffffffff811c2c57>] dput+0xe7/0x1e0
 [<ffffffff811acc3d>] __fput+0x19d/0x2d0
 [<ffffffff811acd7e>] ____fput+0xe/0x10
 [<ffffffff81070645>] task_work_run+0xb5/0xe0
 [<ffffffff81002941>] do_notify_resume+0x71/0xb0
 [<ffffffff8175f14a>] int_signal+0x12/0x17

Reported-and-Tested-by: Chris Fries <C.Fries@motorola.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-05-28 15:03:00 +09:00
Lukas Czerner d47992f86b mm: change invalidatepage prototype to accept length
Currently there is no way to truncate partial page where the end
truncate point is not at the end of the page. This is because it was not
needed and the functionality was enough for file system truncate
operation to work properly. However more file systems now support punch
hole feature and it can benefit from mm supporting truncating page just
up to the certain point.

Specifically, with this functionality truncate_inode_pages_range() can
be changed so it supports truncating partial page at the end of the
range (currently it will BUG_ON() if 'end' is not at the end of the
page).

This commit changes the invalidatepage() address space operation
prototype to accept range to be invalidated and update all the instances
for it.

We also change the block_invalidatepage() in the same way and actually
make a use of the new length argument implementing range invalidation.

Actual file system implementations will follow except the file systems
where the changes are really simple and should not change the behaviour
in any way .Implementation for truncate_page_range() which will be able
to accept page unaligned ranges will follow as well.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Hugh Dickins <hughd@google.com>
2013-05-21 23:17:23 -04:00
Jaegeuk Kim 59bbd474ab f2fs: cover free_nid management with spin_lock
After build_free_nids() searches free nid candidates from nat pages and
current journal blocks, it checks all the candidates if they are allocated
so that the nat cache has its nid with an allocated block address.

In this procedure, previously we used
    list_for_each_entry_safe(fnid, next_fnid, &nm_i->free_nid_list, list).
But, this is not covered by free_nid_list_lock, resulting in null pointer bug.

This patch moves this checking routine inside add_free_nid() in order not to use
the spin_lock.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-05-08 19:54:22 +09:00
Haicheng Li 23d3884427 f2fs: optimize scan_nat_page()
When nm_i->fcnt > 2 * MAX_FREE_NIDS, stop scanning other NAT entries.

Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
[Jaegeuk Kim: fix handling the return value of add_free_nid()]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-05-08 19:54:22 +09:00
Haicheng Li 8760952d92 f2fs: code cleanup for scan_nat_page() and build_free_nids()
This patch does two cleanups:
1. remove unused variable "fcnt" in build_free_nids().
2. make scan_nat_page() as void type and remove useless variable "fcnt".

Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-05-08 19:54:21 +09:00
Haicheng Li 95630cbadc f2fs: bugfix for alloc_nid_failed()
Directly drop the free_nid cache when nm_i->fcnt > 2 * MAX_FREE_NIDS

Since there is NOT nmi->free_nid_list_lock spinlock protection between
a sequential calling of alloc_nid() and alloc_nid_failed(), some other
threads may already add new free_nid to the free_nid_list during this
period.

We need to make sure nmi->fcnt is never > 2 * MAX_FREE_NIDS.

Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
[Jaegeuk Kim: fit the coding style]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-05-08 19:54:20 +09:00
Jaegeuk Kim ac5d156c78 f2fs: modify the number of issued pages to merge IOs
When testing f2fs on an SSD, I found some 128 page IOs followed by 1 page IO
were issued by f2fs_write_node_pages.
This means that there were some mishandling flows which degrades performance.

Previous f2fs_write_node_pages determines the number of pages to be written,
nr_to_write, as follows.

1. The bio_get_nr_vecs returns 129 pages.
2. The bio_alloc makes a room for 128 pages.
3. The initial 128 pages go into one bio.
4. The existing bio is submitted, and a new bio is prepared for the last 1 page.
5. Finally, sync_node_pages submits the last 1 page bio.

The problem is from the use of bio_get_nr_vecs, so this patch replace it
with max_hw_blocks using queue_max_sectors.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-30 12:07:32 +09:00
Haicheng Li 6cac3759ce f2fs: fix inconsistent using of NM_WOUT_THRESHOLD
try_to_free_nats() is usually called with parameter nr_shrink as
	"nm_i->nat_cnt - NM_WOUT_THRESHOLD"
by flush_nat_entries() during checkpointing process.

However, this is inconsistent with the actual threshold check as
	"if (nm_i->nat_cnt < 2 * NM_WOUT_THRESHOLD)"
, which will ignore the free_nats requests when
	NM_WOUT_THRESHOLD < nm_i->nat_cnt < 2 * NM_WOUT_THRESHOLD

So fix the threshold check condition.

Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-30 12:07:32 +09:00
Jaegeuk Kim afcb7ca01f f2fs: check truncation of mapping after lock_page
We call lock_page when we need to update a page after readpage.
Between grab and lock page, the page can be truncated by other thread.
So, we should check the page after lock_page whether it was truncated or not.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-29 11:19:32 +09:00
Jaegeuk Kim 55008d845d f2fs: enhance alloc_nid and build_free_nids flows
In order to avoid build_free_nid lock contention, let's change the order of
function calls as follows.

At first, check whether there is enough free nids.
 - If available, just get a free nid with spin_lock without any overhead.
 - Otherwise, conduct build_free_nids.
  : scan nat pages, journal nat entries, and nat cache entries.

We should consider carefullly not to serve free nids intermediately made by
build_free_nids.
We can get stable free nids only after build_free_nids is done.

Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-29 11:19:21 +09:00
Jaegeuk Kim 9198aceb53 f2fs: check nid == 0 in add_free_nid
It is more obvious that add_free_nid checks whether the free nid is zero or not.

Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-26 10:35:13 +09:00
Jaegeuk Kim c718379b6b f2fs: give a chance to merge IOs by IO scheduler
Previously, background GC submits many 4KB read requests to load victim blocks
and/or its (i)node blocks.

...
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb61, blkaddr = 0x3b964ed
f2fs_gc : block_rq_complete: 8,16 R () 499854968 + 8 [0]
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb6f, blkaddr = 0x3b964ee
f2fs_gc : block_rq_complete: 8,16 R () 499854976 + 8 [0]
f2fs_gc : f2fs_readpage: ino = 1, page_index = 0xb79, blkaddr = 0x3b964ef
f2fs_gc : block_rq_complete: 8,16 R () 499854984 + 8 [0]
...

However, by the fact that many IOs are sequential, we can give a chance to merge
the IOs by IO scheduler.
In order to do that, let's use blk_plug.

...
f2fs_gc : f2fs_iget: ino = 143
f2fs_gc : f2fs_readpage: ino = 143, page_index = 0x1c6, blkaddr = 0x2e6ee
f2fs_gc : f2fs_iget: ino = 143
f2fs_gc : f2fs_readpage: ino = 143, page_index = 0x1c7, blkaddr = 0x2e6ef
<idle> : block_rq_complete: 8,16 R () 1519616 + 8 [0]
<idle> : block_rq_complete: 8,16 R () 1519848 + 8 [0]
<idle> : block_rq_complete: 8,16 R () 1520432 + 96 [0]
<idle> : block_rq_complete: 8,16 R () 1520536 + 104 [0]
<idle> : block_rq_complete: 8,16 R () 1521008 + 112 [0]
<idle> : block_rq_complete: 8,16 R () 1521440 + 152 [0]
<idle> : block_rq_complete: 8,16 R () 1521688 + 144 [0]
<idle> : block_rq_complete: 8,16 R () 1522128 + 192 [0]
<idle> : block_rq_complete: 8,16 R () 1523256 + 328 [0]
...

Note that this issue should be addressed in checkpoint, and some readahead
flows too.

Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-26 10:35:10 +09:00
Namjae Jeon 51dd624934 f2fs: add tracepoints for truncate operation
add tracepoints for tracing the truncate operations
like truncate node/data blocks, f2fs_truncate etc.

Tracepoints are added at entry and exit of operation
to trace the success & failure of operation.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Pankaj Kumar <pankaj.km@samsung.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
[Jaegeuk: combine and modify the tracepoint structures]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-23 16:40:38 +09:00
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 49952fa182 f2fs: reduce redundant spin_lock operations
This patch reduces redundant spin_lock operations in alloc_nid_failed().
The alloc_nid_failed() does not need to delete entry and add one again
by triggering spin_lock and spin_unlock redundantly.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-03 22:19:03 +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 56ae674cc2 f2fs: remove redundant lock_page calls
In get_node_page, we do not need to call lock_page all the time.

If the node page is cached as uptodate,

1. grab_cache_page locks the page,
2. read_node_page unlocks the page, and
3. lock_page is called for further process.

Let's avoid this.

Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-03 17:27:42 +09:00
Alexandru Gheorghiu 79b5793be4 f2fs: use kmemdup
Use kmemdup instead of kzalloc and memcpy.

Signed-off-by: Alexandru Gheorghiu <gheorghiuandru@gmail.com>
Acked-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-03-31 09:12:18 +09:00
Jaegeuk Kim fa37241743 f2fs: remain nat cache entries for further free nid allocation
In the checkpoint flow, the f2fs investigates the total nat cache entries.
Previously, if an entry has NULL_ADDR, f2fs drops the entry and adds the
obsolete nid to the free nid list.
However, this free nid will be reused sooner, resulting in its nat entry miss.
In order to avoid this, we don't need to drop the nat cache entry at this moment.

Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-03-27 09:16:18 +09:00
Jaegeuk Kim 04431c44e5 f2fs: fix not to allocate max_nid
The build_free_nid should not add free nids over nm_i->max_nid.
But, there was a hole that invalid free nid was added by the following scenario.

Let's suppose nm_i->max_nid = 150 and the last NAT page has 100 ~ 200 nids.

build_free_nids
  - get_current_nat_page loads the last NAT page
  - scan_nat_page can add 100 ~ 200 nids
    -> Bug here!
So, when scanning an NAT page, we should check each candidate whether it is
over max_nid or not.

Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-03-20 18:30:13 +09:00
Jaegeuk Kim c3850aa1cb f2fs: fix return value of releasepage for node and data
If the return value of releasepage is equal to zero, the page cannot be reclaimed.
Instead, we should return 1 in order to reclaim clean pages.

Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-03-20 18:30:13 +09:00
Jaegeuk Kim 48cb76c7be f2fs: scan next nat page to reuse free nids in there
When we build new free nids, let's scan the just next NAT page instead of
skipping a couple of previously scanned pages in order to reuse free nids in
there.
Otherwise, we can use too much wide range of nids even though several nids were
deallocated, and also their node pages can be cached in the node_inode's address
space.
This means that we can retain lots of clean pages in the main memory, which
induces mm's reclaiming overhead.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-03-20 18:30:12 +09:00
Jaegeuk Kim 08d8058be6 f2fs: should check the node page was truncated first
Currently, f2fs doesn't reclaim any node pages.
However, if we found that a node page was truncated by checking its block
address with zero during f2fs_write_node_page, we should not skip that node
page and return zero to reclaim it.

Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-03-20 18:30:12 +09:00
Jaegeuk Kim 393ff91f57 f2fs: reduce unncessary locking pages during read
This patch reduces redundant locking and unlocking pages during read operations.
In f2fs_readpage, let's use wait_on_page_locked() instead of lock_page.
And then, when we need to modify any data finally, let's lock the page so that
we can avoid lock contention.

[readpage rule]
- The f2fs_readpage returns unlocked page, or released page too in error cases.
- Its caller should handle read error, -EIO, after locking the page, which
  indicates read completion.
- Its caller should check PageUptodate after grab_cache_page.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-03-20 18:30:06 +09:00
Namjae Jeon 25c0a6e529 f2fs: avoid extra ++ while returning from get_node_path
In all the breaking conditions in get_node_path, 'n' is used to
track index in offset[] array, but while breaking out also, in all
paths n++ is done.
So, remove the ++ from breaking paths. Also, avoid
reset of 'level=0' in first 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>
2013-03-18 21:00:36 +09:00
Namjae Jeon 3aa770a9c9 f2fs: optimize and change return path in lookup_free_nid_list
Optimize and change return path in lookup_free_nid_list

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
Namjae Jeon e0f56cb44b f2fs: optimize get node page readahead part
We can remove the call to find_get_page to get a page from the cache
and check for up-to-date, instead we can make use of grab_cache_page
part itself to fetch the page from the cache.
So, removing the call and moving the PageUptodate at proper place, also
taken care of moving the lock_page condition in the page_hit part.

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 21:00:34 +09:00
Changman Lee 52c2db3f95 f2fs: check the level before calling get_nid function
The caller of get_nid should be careful not to put lower value than
NODE_DIR1_BLOCK in case of level is zero.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-03-18 21:00:34 +09:00
Jaegeuk Kim 266e97a81c f2fs: introduce readahead mode of node pages
Previously, f2fs reads several node pages ahead when get_dnode_of_data is called
with RDONLY_NODE flag.
And, this flag is set by the following functions.
- get_data_block_ro
- get_lock_data_page
- do_write_data_page
- truncate_blocks
- truncate_hole

However, this readahead mechanism is initially introduced for the use of
get_data_block_ro to enhance the sequential read performance.

So, let's clarify all the cases with the additional modes as follows.

enum {
	ALLOC_NODE,	/* allocate a new node page if needed */
	LOOKUP_NODE,	/* look up a node without readahead */
	LOOKUP_NODE_RA,	/*
			 * look up a node with readahead called
			 * by get_datablock_ro.
			 */
}

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
2013-03-18 21:00:33 +09:00
Jaegeuk Kim 66d36a2944 f2fs: read with READ_SYNC when getting dnode page
The get_node_page_ra tries to:
1. grab or read a target node page for the given nid,
2. then, call ra_node_page to read other adjacent node pages in advance.

So, when we try to read a target node page by #1, we should submit bio with
READ_SYNC instead of READA.
And, in #2, READA should be used.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
2013-03-18 21:00:33 +09:00
Jaegeuk Kim 12faafe454 f2fs: fix to unlock node page when it was truncated
If the node page was truncated, its block address became zero.
This means that we don't need to write the node page, but have to unlock
NODE_WRITE, decrease the number of dirty node pages, and then unlock_page
before returning the f2fs_write_node_page with zero.

Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-03-18 21:00:09 +09:00
Jaegeuk Kim 7dd690c820 f2fs: avoid build warning
This patch removes the following build warning:
fs/f2fs/node.c: warning: 'nofs' may be used uninitialized in this function
[-Wuninitialized]:  => 738:8

Note that this is a false alarm.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-02-12 07:28:55 +09:00
Jaegeuk Kim 90b2fc64f0 Merge branch 'f2fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs into dev
Pull f2fs cleanup patches from Al Viro:

f2fs: get rid of fake on-stack dentries
f2fs: switch init_inode_metadata() to passing parent and name separately
f2fs: switch new_inode_page() from dentry to qstr
f2fs: init_dent_inode() should take qstr

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

Conflicts:
	fs/f2fs/recovery.c
2013-02-12 07:17:20 +09:00
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
Jaegeuk Kim 369a708c2a f2fs: remove the use of page_cache_release
Let's remove the use of page_cache_release() in f2fs, and instead, use
f2fs_put_page(page, 0) which is exactly same but for code readability.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-02-12 07:15:01 +09:00
Namjae Jeon a2b52a598a f2fs: reorganize code for ra_node_page
We can remove unneeded label unlock_out, avoid unnecessary jump
and reorganize the returning conditions in this function.

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>
2013-02-12 07:15:01 +09:00
Al Viro c004363dd6 f2fs: switch new_inode_page() from dentry to qstr
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-08 02:55:03 -05:00
Al Viro 53dc9a6776 f2fs: init_dent_inode() should take qstr
for one thing, it doesn't (and shouldn't) use anything else from dentry;
for another, on some call chains the dentry is fake and should
be eliminated completely.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-08 02:55:03 -05:00
Jaegeuk Kim a7fdffbd3e f2fs: avoid issuing small bios due to several dirty node pages
If some small bios of dirty node pages are supposed to be issued during the
sequential data writes, there-in well-produced consecutive data bios are able
to be split by the small node bios, resulting in performance degradation.
So, let's collect a number of dirty node pages until reaching a threshold.
And, by default, I set the threshold as 2MB, a segment size.

This improves sequential write performance on i5, 512GB SSD (830 w/ SATA2) as
follows.
Before: 231 MB/s -> After: 255 MB/s

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
2013-01-22 10:48:59 +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
Jaegeuk Kim 2b50638dec f2fs: clean up unused variables and return values
This patch cleans up a couple of unnecessary codes related to unused variables
and return values.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-12-28 11:27:52 +09:00
Jaegeuk Kim 71e9fec548 f2fs: invalidate the node page if allocation is failed
The new_node_page() is processed as the following procedure.

1. A new node page is allocated.
2. Set PageUptodate with proper footer information.
3. Check if there is a free space for allocation
 4.a. If there is no space, f2fs returns with -ENOSPC.
 4.b. Otherwise, go next.

In the case of step #4.a, f2fs remains a wrong node page in the page cache
with the uptodate flag.

Also, even though a new node page is allocated successfully, an error can be
occurred afterwards due to allocation failure of the other data structures.
In such a case, remove_inode_page() would be triggered, so that we have to
clear uptodate flag in truncate_node() too.

So, we should remove the uptodate flag, if allocation is failed.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-12-28 11:24:09 +09:00
Jaegeuk Kim 398b1ac5a5 f2fs: fix handling errors got by f2fs_write_inode
Ruslan reported that f2fs hangs with an infinite loop in f2fs_sync_file():

	while (sync_node_pages(sbi, inode->i_ino, &wbc) == 0)
		f2fs_write_inode(inode, NULL);

The reason was revealed that the cold flag is not set even thought this inode is
a normal file. Therefore, sync_node_pages() skips to write node blocks since it
only writes cold node blocks.

The cold flag is stored to the node_footer in node block, and whenever a new
node page is allocated, it is set according to its file type, file or directory.

But, after sudden-power-off, when recovering the inode page, f2fs doesn't recover
its cold flag.

So, let's assign the cold flag in more right places.

One more thing:
If f2fs_write_inode() returns an error due to whatever situations, there would
be no dirty node pages so that sync_node_pages() returns zero.
(i.e., zero means nothing was written.)

Reported-by: Ruslan N. Marchenko <me@ruff.mobi>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-12-26 10:39:52 +09:00
Namjae Jeon be4124f872 f2fs: fix the compiler warning for uninitialized use of variable
When CONFIG_CC_OPTIMIZE_FOR_SIZE is enabled in the kernel, -Os optimisation
flag is passed to gcc for compilation, and somehow while trying to optimize
the code, compiler is might not able to see the initialisation of variable
ne struct variable inside the get_node_info() function and results into
following warning:

fs/f2fs/node.c: In function 'get_node_info':
fs/f2fs/node.c:175:3: warning: 'ne.block_addr' may be used uninitialized in
this function [-Wuninitialized]
fs/f2fs/node.c:265:24: note: 'ne.block_addr' was declared here
fs/f2fs/node.c:176:3: warning: 'ne.ino' may be used uninitialized in this
function [-Wuninitialized]
fs/f2fs/node.c:265:24: note: 'ne.ino' was declared here
fs/f2fs/node.c:177:3: warning: 'ne.version' may be used uninitialized in
this function [-Wuninitialized]
fs/f2fs/node.c:265:24: note: 'ne.version' was declared here

Hence, lets initialise the ne struct variable to zero, which will remove
this warning and also doing this does not seems to making any impact on the
code behavior.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Pankaj Kumar <pankaj.km@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 e05df3b115 f2fs: add node operations
This adds specific functions to manage NAT pages, a cache for NAT entries, free
nids, direct/indirect node blocks for indexing data, and address space for node
pages.

- The key information of an NAT entry consists of a node id and a block address.

- An NAT page is composed of block addresses covered by a certain range of NAT
  entries, which is maintained by the address space of meta_inode.

- A radix tree structure is used to cache NAT entries. The index for the tree
  is a node id.

- When there is no free nid, F2FS should scan NAT entries to find new one. In
  order to avoid scanning frequently, F2FS manages a list containing a number of
  free nids in memory. Only when free nids in the list are exhausted, scanning
  process, build_free_nids(), is triggered.

- F2FS has direct and indirect node blocks for indexing data. This patch adds
  fuctions related to the node block management such as getting, allocating, and
  truncating node blocks to index data.

- In order to cache node blocks in memory, F2FS has a node_inode with an address
  space for node pages. This patch also adds the address space operations for
  node_inode.

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