If so many dirty dentry blocks are cached, not reached to the flush condition,
we should fall into livelock in balance_dirty_pages.
So, let's consider the mem size for the condition.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch introduce raw_nat_from_node_info() to simplfy some codes, and also
use exist function node_info_from_raw_nat() to do the same job.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

If multiple redundant fsync calls are triggered, we don't need to write its
node pages with fsync mark continuously.

So, this patch adds FI_NEED_FSYNC to track whether the latest node block is
written with the fsync mark or not.
If the mark was set, a new fsync doesn't need to write a node block.
Otherwise, we should do a new node block with the mark for roll-forward
recovery.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

The NM_WOUT_THRESHOLD is now obsolete since f2fs starts to control on a basis
of the memory footprint.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch introduces ram_thresh, a sysfs entry, which controls the memory
footprint used by the free nid list and the nat cache.

Previously, the free nid list was controlled by MAX_FREE_NIDS, while the nat
cache was managed by NM_WOUT_THRESHOLD.
However, this approach cannot be applied dynamically according to the system.

So, this patch adds ram_thresh that users can specify the threshold, which is
in order of 1 / 1024.
For example, if the total ram size is 4GB and the value is set to 10 by default,
f2fs tries to control the number of free nids and nat caches not to consume over
10 * (4GB / 1024) = 10MB.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch introduces a help function f2fs_has_xattr_block for better
readability.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

The nat cache entry maintains a status whether it is checkpointed or not.
So, if a new cache entry is loaded from the last checkpoint,
nat_entry->checkpointed should be true.
If the cache entry is modified as being dirty, nat_entry->checkpoint should
be false.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Update several comments:
1. use f2fs_{un}lock_op install of mutex_{un}lock_op.
2. update comment of get_data_block().
3. update description of node offset.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch fixes the use of XATTR_NODE_OFFSET.

o The offset should not use several MSB bits which are used by marking node
blocks.

o IS_DNODE should handle XATTR_NODE_OFFSET to avoid potential abnormality
during the fsync call.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Introduce help function F2FS_NODE() to simplify the conversion of node_page to
f2fs_node.
Signed-off-by: NGu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

If a file is linked, f2fs loose its parent inode number so that fsync calls
for the linked file should do checkpoint all the time.
But, if we can recover its parent inode number after the checkpoint, we can
adjust roll-forward mechanism for the further fsync calls, which is able to
improve the fsync performance significatly.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

There are various functions with common code which could be separated
out to make common routines. So, made new routines and in order to
retain the same call path and no major changes, written some macros
to access those routines.
Signed-off-by: NNamjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: NAmit Sahrawat <a.sahrawat@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

If (ofs % (NIDS_PER_BLOCK + 1) == 0), the node is an indirect node block.
Signed-off-by: NZhihui Zhang <zzhsuny@gmail.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

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: NNamjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

When we recover fsync'ed data after power-off-recovery, we should guarantee
that any parent inode number should be correct for each direct inode blocks.

So, let's make the following rules.

- The fsync should do checkpoint to all the inodes that were experienced hard
links.

- So, the only normal files can be recovered by roll-forward.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

As pointed out by Randy Dunlap, this patch removes all usage of "/**" for comment
blocks. Instead, just use "/*".
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

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: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This adds the following major in-memory structures in f2fs.

- f2fs_sb_info:
  contains f2fs-specific information, two special inode pointers for node and
  meta address spaces, and orphan inode management.

- f2fs_inode_info:
  contains vfs_inode and other fs-specific information.

- f2fs_nm_info:
  contains node manager information such as NAT entry cache, free nid list,
  and NAT page management.

- f2fs_node_info:
  represents a node as node id, inode number, block address, and its version.

- f2fs_sm_info:
  contains segment manager information such as SIT entry cache, free segment
  map, current active logs, dirty segment management, and segment utilization.
  The specific structures are sit_info, free_segmap_info, dirty_seglist_info,
  curseg_info.

In addition, add F2FS_SUPER_MAGIC in magic.h.
Signed-off-by: NChul Lee <chur.lee@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>