kmalloc() returns kmalloc'ed memory, and kvmalloc() returns either
kmalloc'ed or vmalloc'ed memory.  But the f2fs wrappers, f2fs_kmalloc()
and f2fs_kvmalloc(), both return both kinds of memory.

It's redundant to have two functions that do the same thing, and also
breaking the standard naming convention is causing bugs since people
assume it's safe to kfree() memory allocated by f2fs_kmalloc().  See
e.g. the various allocations in fs/f2fs/compress.c.

Fix this by making f2fs_kmalloc() just use kmalloc().  And to avoid
re-introducing the allocation failures that the vmalloc fallback was
intended to fix, convert the largest allocations to use f2fs_kvmalloc().

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

Shutdown test is somtimes hung, since it keeps trying to flush dirty node pages
in an inifinite loop. Let's drop dirty pages at umount in that case.

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

There could be a scenario where f2fs_sync_node_pages gets
called during checkpoint, which in turn tries to flush
inline data and calls iput(). This results in deadlock as
iput() tries to hold cp_rwsem, which is already held at the
beginning by checkpoint->block_operations().

Call stack :

Thread A		Thread B
f2fs_write_checkpoint()
- block_operations(sbi)
 - f2fs_lock_all(sbi);
  - down_write(&sbi->cp_rwsem);

                        - open()
                         - igrab()
                        - write() write inline data
                        - unlink()
- f2fs_sync_node_pages()
 - if (is_inline_node(page))
  - flush_inline_data()
   - ilookup()
     page = f2fs_pagecache_get_page()
     if (!page)
      goto iput_out;
     iput_out:
			-close()
			-iput()
       iput(inode);
       - f2fs_evict_inode()
        - f2fs_truncate_blocks()
         - f2fs_lock_op()
           - down_read(&sbi->cp_rwsem);

Fixes: 2049d4fcb057 ("f2fs: avoid multiple node page writes due to inline_data")
Signed-off-by: Sayali Lokhande <sayalil@codeaurora.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

In f2fs_try_to_free_nids(), .nid_list_lock spinlock critical region will
increase as expected shrink number increase, to avoid spining other CPUs
for long time, we change to release nid caches with small batch each time
under .nid_list_lock coverage.

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

Adds to support accounting read IOs from userspace/kernel.

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

Data flush can generate heavy IO and cause long latency during
flush, so it's not appropriate to trigger it in foreground
operation.

And also, we may face below potential deadlock during data flush:
- f2fs_write_multi_pages
 - f2fs_write_raw_pages
  - f2fs_write_single_data_page
   - f2fs_balance_fs
    - f2fs_balance_fs_bg
     - f2fs_sync_dirty_inodes
      - filemap_fdatawrite   -- stuck on flush same cluster

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

In order to avoid polluting global slab cache namespace.

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

As Geert Uytterhoeven reported:

for parameter HZ/50 in congestion_wait(BLK_RW_ASYNC, HZ/50);

On some platforms, HZ can be less than 50, then unexpected 0 timeout
jiffies will be set in congestion_wait().

This patch introduces a macro DEFAULT_IO_TIMEOUT to wrap a determinate
value with msecs_to_jiffies(20) to instead HZ/50 to avoid such issue.

Quoted from Geert Uytterhoeven:

"A timeout of HZ means 1 second.
HZ/50 means 20 ms, but has the risk of being zero, if HZ < 50.

If you want to use a timeout of 20 ms, you best use msecs_to_jiffies(20),
as that takes care of the special cases, and never returns 0."

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

- rename datablock_addr() to data_blkaddr().
- wrap data_blkaddr() with f2fs_data_blkaddr() to clean up
parameters.

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

Lack of maintenance on comments may mislead developers, fix them.

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