This patch allows fscrypto to handle a second key prefix given by filesystem.
The main reason is to provide backward compatibility, since previously f2fs
used "f2fs:" as a crypto prefix instead of "fscrypt:".
Later, ext4 should also provide key_prefix() to give "ext4:".

One concern decribed by Ted would be kinda double check overhead of prefixes.
In x86, for example, validate_user_key consumes 8 ms after boot-up, which turns
out derive_key_aes() consumed most of the time to load specific crypto module.
After such the cold miss, it shows almost zero latencies, which treats as a
negligible overhead.
Note that request_key() detects wrong prefix in prior to derive_key_aes() even.

Cc: Ted Tso <tytso@mit.edu>
Cc: stable@vger.kernel.org # v4.6
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

The following panic occurs when truncating inode which has inline
xattr to max filesize.

[<ffffffffa013d3be>] get_dnode_of_data+0x4e/0x580 [f2fs]
[<ffffffffa013aca1>] ? read_node_page+0x51/0x90 [f2fs]
[<ffffffffa013ad99>] ? get_node_page.part.34+0xb9/0x170 [f2fs]
[<ffffffffa01235b1>] truncate_blocks+0x131/0x3f0 [f2fs]
[<ffffffffa01238e3>] f2fs_truncate+0x73/0x100 [f2fs]
[<ffffffffa01239d2>] f2fs_setattr+0x62/0x2a0 [f2fs]
[<ffffffff811a72c8>] notify_change+0x158/0x300
[<ffffffff8118a42b>] do_truncate+0x6b/0xa0
[<ffffffff8118e539>] ? __sb_start_write+0x49/0x100
[<ffffffff8118a798>] do_sys_ftruncate.constprop.12+0x118/0x170
[<ffffffff8118a82e>] SyS_ftruncate+0xe/0x10
[<ffffffff8169efcf>] tracesys+0xe1/0xe6
[<ffffffffa0139ae0>] get_node_path+0x210/0x220 [f2fs]
 <ffff880206a89ce8>
--[ end trace 5fea664dfbcc6625 ]---

The reason is truncate_blocks tries to truncate all node and data blocks
start from specified block offset with value of (max filesize / block
size), but actually, our valid max block offset is (max filesize / block
size) - 1, so f2fs detects such invalid block offset with BUG_ON in
truncation path.

This patch lets f2fs skip truncating data which is exceeding max
filesize.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Currently, generic_block_bmap is used in f2fs_bmap, its semantics is when
the mapping is been found, return position of target physical block,
otherwise return zero.

But, previously, when there is no mapping info for specified logical block,
f2fs_bmap will map target physical block to a uninitialized variable, which
should be wrong. Fix it.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch removes an obsolete variable used in add_free_nid.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Even if an inode failed to release its blocks, it should be kept in an orphan
inode list, so it will be released later.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Restructure struct seg_entry to eliminate holes in it, after that,
in 32-bits machine, it reduces size from 32 bytes to 24 bytes; in
64-bits machine, it reduces size from 56 bytes to 40 bytes.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Reuse get_extent_info for readability.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Each of fields in struct f2fs_xattr_entry will be assigned later,
so previously we don't need to memset the struct.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

In find_fsync_dnodes, get_tmp_page will read dnode page synchronously,
previously, ra_meta_page did the same work, which is redundant, remove
it.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch modifies to retry truncating node blocks in -ENOMEM case.
Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

When unmounting filesystem, we should release all the ino entries.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch fixes a couple of bugs regarding to orphan inodes when handling
errors.

This tries to
 - call alloc_nid_done with add_orphan_inode in handle_failed_inode
 - let truncate blocks in f2fs_evict_inode
 - not make a bad inode due to i_mode change
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch injects ENOSPC failures.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch adds page allocation failures.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch injects kmalloc failure given a fault injection rate.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch adds a mount option to select fault ratio.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch converts grab_cache_page to f2fs_grab_cache_page.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch adds f2fs_kmalloc.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch adds a new proc entry to show segment information in more detail.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This adds macros to be used multiple proc entries.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Factor out fsync inode entry operations into {add,del}_fsync_inode.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Commit 28bc106b ("f2fs: support revoking atomic written pages")
forgot to clear page private flag correctly, fix it.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Private data in page should be removed during ->releasepage or
->invalidatepage, otherwise garbage data would be remained in that page.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Commit 57b62d29 ("f2fs: fix to report
error in f2fs_readdir") causes f2fs_readdir to return -ENOENT when
get_lock_data_page returns -ENOENT. However, the original logic is to
continue when get_lock_data_page returns -ENOENT, but it forgets to
reset err to 0.

This will cause getdents64 incorretly return -ENOENT when lastdirent is
NULL in getdents64. This will lead to a wrong return value for syscall
caller.
Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

For foreground GC, we cache node blocks in victim section and set them
dirty, then we call sync_node_pages to flush these node pages, but
meanwhile, those node pages which does not locate in victim section
will be flushed together, so more bandwidth and continuous free space
would be occupied.

So for this condition, it's better to leave those unrelated node page
in cache for further write hit, and let CP or VM to flush them afterward.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

The filename length in dirent of may become zero-sized after random junk
data injection, once encounter such dirent, find_target_dentry or
f2fs_add_inline_entries will run into an infinite loop. So let f2fs being
aware of that to avoid deadloop.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

I've changed employer, update my email address to the new one.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Under direct IO path with O_(D)SYNC, it needs to set proper APPEND or UPDATE
flags, so taht f2fs_sync_file can make its data safe.
Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

In order to give atomic writes, we should consider power failure during
sync_node_pages in fsync.
So, this patch marks fsync flag only in the last dnode block.
Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

The fsync_node_pages should return pass or failure so that user could know
fsync is completed or not.
Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch splits the existing sync_node_pages into (f)sync_node_pages.
The fsync_node_pages is used for f2fs_sync_file only.
Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

The first page of volatile writes usually contains a sort of header information
which will be used for recovery.
(e.g., journal header of sqlite)

If this is written without other journal data, user needs to handle the stale
journal information.
Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

When fsync is called, sync_node_pages finds a proper direct node pages to flush.
But, it locks unrelated direct node pages together unnecessarily.
Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

If somebody wrote some data before atomic writes, we should flush them in order
to handle atomic data in a right period.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

If we committed atomic write successfully, we don't need to invalidate pages.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch returns -E2BIG if there is no space to add an xattr entry.
This should fix generic/026 in xfstests as well.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch resolves the redundant condition check reported by David.
Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

The atomic/volatile operation should be done in pair of start and commit
ioctl.
For example, if a killed process remains open-ended atomic operation, we should
drop its flag as well as its atomic data. Otherwise, if sqlite initiates another
operation which doesn't require atomic writes, it will lose every data, since
f2fs still treats with them as atomic writes; nobody will trigger its commit.
Reported-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

When one reader closes its file while the other writer is doing atomic writes,
f2fs_release_file drops atomic data resulting in an empty commit.
This patch fixes this wrong commit problem by checking openess of the file.

 Process0                       Process1
 				open file
 start atomic write
 write data
 read data
				close file
				f2fs_release_file()
				clear atomic data
 commit atomic write
Reported-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch adds BUG_ON instead of retrying loop.
In the case of node pages, we already got this inode page, but unlocked it.
By the fact that we don't truncate any node pages in operations, the page's
mapping should be unchangeable.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>