Reading past end of file returns EOF for aligned reads but -EINVAL for
unaligned reads on f2fs.  While documentation is not strict about this
corner case, most filesystem returns EOF on this case, like iomap
filesystems.  This patch consolidates the behavior for f2fs, by making
it return EOF(0).

it can be verified by a read loop on a file that does a partial read
before EOF (A file that doesn't end at an aligned address).  The
following code fails on an unaligned file on f2fs, but not on
btrfs, ext4, and xfs.

  while (done < total) {
    ssize_t delta = pread(fd, buf + done, total - done, off + done);
    if (!delta)
      break;
    ...
  }

It is arguable whether filesystems should actually return EOF or
-EINVAL, but since iomap filesystems support it, and so does the
original DIO code, it seems reasonable to consolidate on that.

Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Pull f2fs updates from Jaegeuk Kim:
 "In this round, we've added two small interfaces: (a) GC_URGENT_LOW
  mode for performance and (b) F2FS_IOC_SEC_TRIM_FILE ioctl for
  security.

  The new GC mode allows Android to run some lower priority GCs in
  background, while new ioctl discards user information without race
  condition when the account is removed.

  In addition, some patches were merged to address latency-related
  issues. We've fixed some compression-related bug fixes as well as edge
  race conditions.

  Enhancements:
   - add GC_URGENT_LOW mode in gc_urgent
   - introduce F2FS_IOC_SEC_TRIM_FILE ioctl
   - bypass racy readahead to improve read latencies
   - shrink node_write lock coverage to avoid long latency

  Bug fixes:
   - fix missing compression flag control, i_size, and mount option
   - fix deadlock between quota writes and checkpoint
   - remove inode eviction path in synchronous path to avoid deadlock
   - fix to wait GCed compressed page writeback
   - fix a kernel panic in f2fs_is_compressed_page
   - check page dirty status before writeback
   - wait page writeback before update in node page write flow
   - fix a race condition between f2fs_write_end_io and f2fs_del_fsync_node_entry

  We've added some minor sanity checks and refactored trivial code
  blocks for better readability and debugging information"

* tag 'f2fs-for-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (52 commits)
  f2fs: prepare a waiter before entering io_schedule
  f2fs: update_sit_entry: Make the judgment condition of f2fs_bug_on more intuitive
  f2fs: replace test_and_set/clear_bit() with set/clear_bit()
  f2fs: make file immutable even if releasing zero compression block
  f2fs: compress: disable compression mount option if compression is off
  f2fs: compress: add sanity check during compressed cluster read
  f2fs: use macro instead of f2fs verity version
  f2fs: fix deadlock between quota writes and checkpoint
  f2fs: correct comment of f2fs_exist_written_data
  f2fs: compress: delay temp page allocation
  f2fs: compress: fix to update isize when overwriting compressed file
  f2fs: space related cleanup
  f2fs: fix use-after-free issue
  f2fs: Change the type of f2fs_flush_inline_data() to void
  f2fs: add F2FS_IOC_SEC_TRIM_FILE ioctl
  f2fs: should avoid inode eviction in synchronous path
  f2fs: segment.h: delete a duplicated word
  f2fs: compress: fix to avoid memory leak on cc->cpages
  f2fs: use generic names for generic ioctls
  f2fs: don't keep meta inode pages used for compressed block migration
  ...

Pull uninitialized_var() macro removal from Kees Cook:
 "This is long overdue, and has hidden too many bugs over the years. The
  series has several "by hand" fixes, and then a trivial treewide
  replacement.

   - Clean up non-trivial uses of uninitialized_var()

   - Update documentation and checkpatch for uninitialized_var() removal

   - Treewide removal of uninitialized_var()"

* tag 'uninit-macro-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  compiler: Remove uninitialized_var() macro
  treewide: Remove uninitialized_var() usage
  checkpatch: Remove awareness of uninitialized_var() macro
  mm/debug_vm_pgtable: Remove uninitialized_var() usage
  f2fs: Eliminate usage of uninitialized_var() macro
  media: sur40: Remove uninitialized_var() usage
  KVM: PPC: Book3S PR: Remove uninitialized_var() usage
  clk: spear: Remove uninitialized_var() usage
  clk: st: Remove uninitialized_var() usage
  spi: davinci: Remove uninitialized_var() usage
  ide: Remove uninitialized_var() usage
  rtlwifi: rtl8192cu: Remove uninitialized_var() usage
  b43: Remove uninitialized_var() usage
  drbd: Remove uninitialized_var() usage
  x86/mm/numa: Remove uninitialized_var() usage
  docs: deprecated.rst: Add uninitialized_var()

In f2fs_read_multi_pages(), we don't have to check cluster's type
again, since overwrite or partial truncation need page lock in
cluster which has already been held by reader, so cluster's type
is stable, let's change check condition to sanity check.

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

We missed to update isize of compressed file in write_end() with
below case:

cluster size is 16KB

- write 14KB data from offset 0
- overwrite 16KB data from offset 0

Fixes: 4c8ff7095bef ("f2fs: support data compression")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Just for code style, no logic change
1. delete useless space
2. change spaces into tab

Signed-off-by: Jack Qiu <jack.qiu@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This is an effort to eliminate the uninitialized_var() macro[1].

The use of this macro is the wrong solution because it forces off ANY
analysis by the compiler for a given variable. It even masks "unused
variable" warnings.

Quoted from Linus[2]:

"It's a horrible thing to use, in that it adds extra cruft to the
source code, and then shuts up a compiler warning (even the _reliable_
warnings from gcc)."

Fix it by remove this variable since it is not needed at all.

[1] https://github.com/KSPP/linux/issues/81
[2] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/

Suggested-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Link: https://lore.kernel.org/r/20200615085132.166470-1-yanaijie@huawei.com
Signed-off-by: Kees Cook <keescook@chromium.org>

Wire up f2fs to support inline encryption via the helper functions which
fs/crypto/ now provides.  This includes:

- Adding a mount option 'inlinecrypt' which enables inline encryption
  on encrypted files where it can be used.

- Setting the bio_crypt_ctx on bios that will be submitted to an
  inline-encrypted file.

- Not adding logically discontiguous data to bios that will be submitted
  to an inline-encrypted file.

- Not doing filesystem-layer crypto on inline-encrypted files.

This patch includes a fix for a race during IPU by
Sahitya Tummala <stummala@codeaurora.org>

Signed-off-by: Satya Tangirala <satyat@google.com>
Acked-by: Jaegeuk Kim <jaegeuk@kernel.org>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Link: https://lore.kernel.org/r/20200702015607.1215430-4-satyat@google.com
Co-developed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>

If two readahead threads having same offset enter in readpages, every read
IOs are split and issued to the disk which giving lower bandwidth.

This patch tries to avoid redundant readahead calls.

Fixes one build error reported by Randy.
Fix build error when F2FS_FS_COMPRESSION is not set/enabled.
This label is needed in either case.

../fs/f2fs/data.c: In function ‘f2fs_mpage_readpages’:
../fs/f2fs/data.c:2327:5: error: label ‘next_page’ used but not defined
     goto next_page;

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

The parameter op_flag is not used in f2fs_get_read_data_page(),
but it is used in f2fs_grab_read_bio(). Obviously, op_flag is
not passed to f2fs_grab_read_bio() successfully. We need to add
parameter in f2fs_submit_page_read() to pass it.

The case:
- gc_data_segment
 - f2fs_get_read_data_page(.., op_flag = REQ_RAHEAD,..)
  - f2fs_submit_page_read
   - f2fs_grab_read_bio(.., op_flag = 0, ..)

Signed-off-by: Jia Yang <jiayang5@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>