This patch adds encryption support in read and write paths.

Note that, in f2fs, we need to consider cleaning operation.
In cleaning procedure, we must avoid encrypting and decrypting written blocks.
So, this patch implements move_encrypted_block().
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch activates the following APIs for encryption support.

The rules quoted by ext4 are:
 - An unencrypted directory may contain encrypted or unencrypted files
   or directories.
 - All files or directories in a directory must be protected using the
   same key as their containing directory.
 - Encrypted inode for regular file should not have inline_data.
 - Encrypted symlink and directory may have inline_data and inline_dentry.

This patch activates the following APIs.
1. f2fs_link              : validate context
2. f2fs_lookup            :      ''
3. f2fs_rename            :      ''
4. f2fs_create/f2fs_mkdir : inherit its dir's context
5. f2fs_direct_IO         : do buffered io for regular files
6. f2fs_open              : check encryption info
7. f2fs_file_mmap         :      ''
8. f2fs_setattr           :      ''
9. f2fs_file_write_iter   :      ''           (Called by sys_io_submit)
10. f2fs_fallocate        : do not support fcollapse
11. f2fs_evict_inode      : free_encryption_info
Signed-off-by: NMichael Halcrow <mhalcrow@google.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds filename encryption infra.
Most of codes are copied from ext4 part, but changed to adjust f2fs
directory structure.
Signed-off-by: NUday Savagaonkar <savagaon@google.com>
Signed-off-by: NIldar Muslukhov <ildarm@google.com>
Signed-off-by: NMichael Halcrow <mhalcrow@google.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch copies from encrypt_key.c in ext4, and modifies for f2fs.

Use GFP_NOFS, since _f2fs_get_encryption_info is called under f2fs_lock_op.
Signed-off-by: NMichael Halcrow <mhalcrow@google.com>
Signed-off-by: NIldar Muslukhov <muslukhovi@gmail.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Most of parts were copied from ext4, except:

 - add f2fs_restore_and_release_control_page which returns control page and
   restore control page
 - remove ext4_encrypted_zeroout()
 - remove sbi->s_file_encryption_mode & sbi->s_dir_encryption_mode
 - add f2fs_end_io_crypto_work for mpage_end_io
Signed-off-by: NMichael Halcrow <mhalcrow@google.com>
Signed-off-by: NIldar Muslukhov <ildarm@google.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds encryption policy and password salt support through ioctl
implementation.

It adds three ioctls:
 F2FS_IOC_SET_ENCRYPTION_POLICY,
 F2FS_IOC_GET_ENCRYPTION_POLICY,
 F2FS_IOC_GET_ENCRYPTION_PWSALT, which use xattr operations.

Note that, these definition and codes are taken from ext4 crypto support.
For f2fs, xattr operations and on-disk flags for superblock and inode were
changed.
Signed-off-by: NMichael Halcrow <mhalcrow@google.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Signed-off-by: NIldar Muslukhov <muslukhovi@gmail.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch add some definition for enrcyption xattr.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds f2fs encryption config.

This patch integrates:

"ext4 crypto: require CONFIG_CRYPTO_CTR if ext4 encryption is enabled

On arm64 this is apparently needed for CTS mode to function correctly.
Otherwise attempts to use CTS return ENOENT."
Signed-off-by: NMichael Halcrow <mhalcrow@google.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This definitions will be used by inode and superblock for encyption.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch slightly changes f2fs_fiemap function to report unwritten area.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch fixes overflow when do cat /sys/kernel/debug/f2fs/status.
If a section is relatively large, dist value can be overflowed.
Reported-by: NYossi Goldfill <ygoldfill@radianmemory.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Now, FALLOC_FL_ZERO_RANGE flag in ->fallocate is supported in ext4/xfs.

In commit, the semantics of this flag is descripted as following:"
1) Make sure that both offset and len are block size aligned.
2) Update the i_size of inode by len bytes.
3) Compute the file's logical block number against offset. If the computed
   block number is not the starting block of the extent, split the extent
   such that the block number is the starting block of the extent.
4) Shift all the extents which are lying between
   [offset, last allocated extent] towards right by len bytes. This step
   will make a hole of len bytes at offset."

This patch implements fallocate's FALLOC_FL_ZERO_RANGE for f2fs.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Now, FALLOC_FL_COLLAPSE_RANGE flag in ->fallocate is supported in ext4/xfs.

In commit, the semantics of this flag is descripted as following:"
1) It collapses the range lying between offset and length by removing any
   data blocks which are present in this range and than updates all the
   logical offsets of extents beyond "offset + len" to nullify the hole
   created by removing blocks. In short, it does not leave a hole.
2) It should be used exclusively. No other fallocate flag in combination.
3) Offset and length supplied to fallocate should be fs block size aligned
   in case of xfs and ext4.
4) Collaspe range does not work beyond i_size."

This patch implements fallocate's FALLOC_FL_COLLAPSE_RANGE for f2fs.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Introduce a generic function replace_block base on recover_data_page,
and export it. So with it we can operate file's meta data which is in
CP/SSA area when we invoke fallocate with FALLOC_FL_COLLAPSE_RANGE
flag.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

In set_node_addr, we try to lookup cached nat entry of inode and then
set flag in it.

But previously in this function, we have already grabbed nat entry with
current node id, if the node id is the same as the one of inode, we
do not need to lookup it in cache again.

So this patch adds condition judgment for reducing unneeded lookup.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Remove f2fs_make_empty() declaration, since the main body of this function
is move into do_make_empty_dir() and the function is obsolete now.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch determines to issue discard commands by comparing given minlen and
the length of produced final candidates.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds a bitmap for discard issues from f2fs_trim_fs.
There-in rule is to issue discard commands only for invalidated blocks
after mount.
Once mount is done, f2fs_trim_fs trims out whole invalid area.
After ehn, it will not issue and discrads redundantly.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch removes spin_lock, since this is covered by f2fs_lock_op already.
And, we should avoid to use page operations inside spin_lock.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch splits find_data_page as follows.

1. f2fs_gc
 - use get_read_data_page() with read only

2. find_in_level
 - use find_data_page without locked page

3. truncate_partial_page
 - In the case cache_only mode, just drop cached page.
 - Ohterwise, use get_lock_data_page() and guarantee to truncate
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch fixes to count the missing symlink case.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch introduces need_dentry_mark() to clean up and avoid redundant
node locks.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

There are two threads:
 f2fs_delete_entry()              get_new_data_page()
                                  f2fs_reserve_block()
				  dn.blkaddr = XXX
 lock_page(dentry_block)
 truncate_hole()
 dn.blkaddr = NULL
 unlock_page(dentry_block)
                                  lock_page(dentry_block)
                                  fill the block from XXX address
                                  add new dentries
                                  unlock_page(dentry_block)

Later, f2fs_write_data_page() will truncate the dentry_block, since
its block address is NULL.

The reason for this was due to the wrong lock order.
In this case, we should do f2fs_reserve_block() after locking its dentry block.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds an inline function to check dot and dotdot names.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch moves getting victim page into move_data_page.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds f2fs_sb_info and page pointers in f2fs_io_info structure.
With this change, we can reduce a lot of parameters for IO functions.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds f2fs_may_inline_data and f2fs_may_inline_dentry.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch cleans up to avoid deep indentation.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch implements f2fs_mpage_readpages for further optimization on
encryption support.

The basic code was taken from fs/mpage.c, and changed to be simple by adjusting
that block_size is equal to page_size in f2fs.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch introduces f2fs_commit_super to write updated superblock.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch introduces f2fs_map_blocks structure likewise ext4_map_blocks.
Now, f2fs uses f2fs_map_blocks when handling get_block.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch introduces a feature in superblock, which will indicate any new
features for f2fs.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch moves some inode-related definitions from node.h to f2fs.h to
add new features.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

has_fsynced_inode() has no other caller out of node.c, make it static.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

In the punch_hole(), if offset bigger than inode size, it returns SUCCESS.
Then f2fs_fallocate() will update time and dirty mark.
In that case, inode has not been modified actually.
So I have added offset check routine that prevent to call the punch_hole().
Signed-off-by: NTaehee Yoo <ap420073@gmail.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Export is_valid_blkaddr() and use it to replace some codes for readability.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Our f2fs_acl_create is copied from posix_acl_create in ./fs/posix_acl.c and
modified to avoid deadlock bug when inline_dentry feature is enabled.

Dan Carpenter rewrites posix_acl_create in commit 2799563b281f
("fs/posix_acl.c: make posix_acl_create() safer and cleaner") to make this
function more safer, so that we can avoid potential bug in its caller,
especially for ocfs2.

Let's back port the patch to f2fs.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

The page_follow_link_light returns NULL and its error pointer was remained
in nd->path.
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This reports performance regression by Yuanhan Liu.
The basic idea was to reduce one-point mutex, but it turns out this causes
another contention like context swithes.

https://lkml.org/lkml/2015/4/21/11

Until finishing the analysis on this issue, I'd like to revert this for a while.

This reverts commit 78373b73.

This patch adds CP_RECOVERY to remain recovery information for checkpoint.
And, it makes sure writing checkpoint in this case.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>