linux-toradex.git/fs/f2fs, branch v3.18-rc5

f2fs: support volatile operations for transient data

2014-10-07T18:54:41+00:00

This patch adds support for volatile writes which keep data pages in memory
until f2fs_evict_inode is called by iput.

For instance, we can use this feature for the sqlite database as follows.
While supporting atomic writes for main database file, we can keep its journal
data temporarily in the page cache by the following sequence.

1. open
 -> ioctl(F2FS_IOC_START_VOLATILE_WRITE);
2. writes
 : keep all the data in the page cache.
3. flush to the database file with atomic writes
  a. ioctl(F2FS_IOC_START_ATOMIC_WRITE);
  b. writes
  c. ioctl(F2FS_IOC_COMMIT_ATOMIC_WRITE);
4. close
 -> drop the cached data

Signed-off-by: Jaegeuk Kim

f2fs: support atomic writes

2014-10-07T00:39:50+00:00

This patch introduces a very limited functionality for atomic write support.
In order to support atomic write, this patch adds two ioctls:
 o F2FS_IOC_START_ATOMIC_WRITE
 o F2FS_IOC_COMMIT_ATOMIC_WRITE

The database engine should be aware of the following sequence.
1. open
 -> ioctl(F2FS_IOC_START_ATOMIC_WRITE);
2. writes
  : all the written data will be treated as atomic pages.
3. commit
 -> ioctl(F2FS_IOC_COMMIT_ATOMIC_WRITE);
  : this flushes all the data blocks to the disk, which will be shown all or
  nothing by f2fs recovery procedure.
4. repeat to #2.

The IO pattens should be:

  ,- START_ATOMIC_WRITE                  ,- COMMIT_ATOMIC_WRITE
 CP | D D D D D D | FSYNC | D D D D | FSYNC ...
                      `- COMMIT_ATOMIC_WRITE

Signed-off-by: Jaegeuk Kim

f2fs: remove unused return value

2014-10-06T04:05:15+00:00

Don't return any value without any usage.

Signed-off-by: Jaegeuk Kim

f2fs: clean up f2fs_ioctl functions

2014-09-30T22:34:56+00:00

This patch cleans up f2fs_ioctl functions for better readability.

Signed-off-by: Jaegeuk Kim

f2fs: potential shift wrapping buf in f2fs_trim_fs()

2014-09-30T22:34:56+00:00

My static checker complains that segment is a u64 but only the lower 31
bits can be used before we hit a shift wrapping bug.

Signed-off-by: Dan Carpenter 
Signed-off-by: Jaegeuk Kim

f2fs: call f2fs_unlock_op after error was handled

2014-09-30T22:34:55+00:00

This patch relocates f2fs_unlock_op in every directory operations to be called
after any error was processed.
Otherwise, the checkpoint can be entered with valid node ids without its
dentry when -ENOSPC is occurred.

Signed-off-by: Jaegeuk Kim

f2fs: check the use of macros on block counts and addresses

2014-09-30T22:34:47+00:00

This patch cleans up the existing and new macros for readability.

Rule is like this.

         ,-----------------------------------------> MAX_BLKADDR -,
         |  ,------------- TOTAL_BLKS ----------------------------,
         |  |                                                     |
         |  ,- seg0_blkaddr   ,----- sit/nat/ssa/main blkaddress  |
block    |  | (SEG0_BLKADDR)  | | | |   (e.g., MAIN_BLKADDR)      |
address  0..x................ a b c d .............................
            |                                                     |
global seg# 0...................... m .............................
            |                       |                             |
            |                       `------- MAIN_SEGS -----------'
            `-------------- TOTAL_SEGS ---------------------------'
                                    |                             |
 seg#                               0..........xx..................

= Note =
 o GET_SEGNO_FROM_SEG0 : blk address -> global segno
 o GET_SEGNO           : blk address -> segno
 o START_BLOCK         : segno -> starting block address

Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: refactor flush_nat_entries to remove costly reorganizing ops

2014-09-30T22:30:41+00:00

Previously, f2fs tries to reorganize the dirty nat entries into multiple sets
according to its nid ranges. This can improve the flushing nat pages, however,
if there are a lot of cached nat entries, it becomes a bottleneck.

This patch introduces a new set management flow by removing dirty nat list and
adding a series of set operations when the nat entry becomes dirty.

Signed-off-by: Jaegeuk Kim

f2fs: introduce FITRIM in f2fs_ioctl

2014-09-30T22:06:09+00:00

This patch introduces FITRIM in f2fs_ioctl.
In this case, f2fs will issue small discards and prefree discards as many as
possible for the given area.

Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: introduce cp_control structure

2014-09-30T22:01:28+00:00

This patch add a new data structure to control checkpoint parameters.
Currently, it presents the reason of checkpoint such as is_umount and normal
sync.

Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim