This patch fixes the issue introduced by the ext4 crypto fix in a same manner.
For F2FS, however, we flush the pending IOs and wait for a while to acquire free
memory.

Fixes: c9af28fdd4492 ("ext4 crypto: don't let data integrity writebacks fail with ENOMEM")
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch synced with the below two ext4 crypto fixes together.

In 4.6-rc1, f2fs newly introduced accessing f_path.dentry which crashes
overlayfs. To fix, now we need to use file_dentry() to access that field.

Fixes: c0a37d487884 ("ext4: use file_dentry()")
Fixes: 9dd78d8c9a7b ("ext4: use dget_parent() in ext4_file_open()")
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Pull f2fs fixes from Jaegeuk Kim.

* tag 'f2fs-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs:
  f2fs: retrieve IO write stat from the right place
  f2fs crypto: fix corrupted symlink in encrypted case
  f2fs: cover large section in sanity check of super

PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized.  And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE.  And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special.  They are
not.

The changes are pretty straight-forward:

 - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

 - page_cache_get() -> get_page();

 - page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below.  For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach.  I'll
fix them manually in a separate patch.  Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In the following patch,

    f2fs: split journal cache from curseg cache

journal cache is split from curseg cache. So IO write statistics should be
retrived from journal cache but not curseg->sum_blk. Otherwise, it will
get 0, and the stat is lost.

Signed-off-by: Shuoran Liu <liushuoran@huawei.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

In the encrypted symlink case, we should check its corrupted symname after
decrypting it.
Otherwise, we can report -ENOENT incorrectly, if encrypted symname starts with
'\0'.

Cc: stable 4.5+ <stable@vger.kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch fixes the bug which does not cover a large section case when checking
the sanity of superblock.
If f2fs detects misalignment, it will fix the superblock during the mount time,
so it doesn't need to trigger fsck.f2fs further.

Reported-by: Matthias Prager <linux@matthiasprager.de>
Reported-by: David Gnedt <david.gnedt@davizone.at>
Cc: stable 4.5+ <stable@vger.kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

If many threads calls fsync with data writes, we don't need to flush every
bios having node page writes.
The f2fs_wait_on_page_writeback will flush its bios when the page is really
needed.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

The f2fs_setxattr() prototype for CONFIG_F2FS_FS_XATTR=n has
been wrong for a long time, since 8ae8f1627f39 ("f2fs: support
xattr security labels"), but there have never been any callers,
so it did not matter.

Now, the function gets called from f2fs_ioc_keyctl(), which
causes a build failure:

fs/f2fs/file.c: In function 'f2fs_ioc_keyctl':
include/linux/stddef.h:7:14: error: passing argument 6 of 'f2fs_setxattr' makes integer from pointer without a cast [-Werror=int-conversion]
 #define NULL ((void *)0)
              ^
fs/f2fs/file.c:1599:27: note: in expansion of macro 'NULL'
     value, F2FS_KEY_SIZE, NULL, type);
                           ^
In file included from ../fs/f2fs/file.c:29:0:
fs/f2fs/xattr.h:129:19: note: expected 'int' but argument is of type 'void *'
 static inline int f2fs_setxattr(struct inode *inode, int index,
                   ^
fs/f2fs/file.c:1597:9: error: too many arguments to function 'f2fs_setxattr'
  return f2fs_setxattr(inode, F2FS_XATTR_INDEX_KEY,
         ^
In file included from ../fs/f2fs/file.c:29:0:
fs/f2fs/xattr.h:129:19: note: declared here
 static inline int f2fs_setxattr(struct inode *inode, int index,

Thsi changes the prototype of the empty stub function to match
that of the actual implementation. This will not make the key
management work when F2FS_FS_XATTR is disabled, but it gets it
to build at least.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

During ->lookup, I_NEW state of inode was been cleared in f2fs_iget,
so in error path, we don't need to clear it again.

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>