ext4: Fix warning in ext4_da_release_space

hulk inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I58KLD


CVE: NA

---------------------------

We got issue as follows:
WARNING: CPU: 2 PID: 1936 at fs/ext4/inode.c:1511 ext4_da_release_space+0x1b9/0x266
Modules linked in:
CPU: 2 PID: 1936 Comm: dd Not tainted 5.10.0+ #344
RIP: 0010:ext4_da_release_space+0x1b9/0x266
RSP: 0018:ffff888127307848 EFLAGS: 00010292
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff843f67cc
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffed1024e60ed9
RBP: ffff888124dc8140 R08: 0000000000000083 R09: ffffed1075da6d23
R10: ffff8883aed36917 R11: ffffed1075da6d22 R12: ffff888124dc83f0
R13: ffff888124dc844c R14: ffff888124dc8168 R15: 000000000000000c
FS:  00007f6b7247d740(0000) GS:ffff8883aed00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc1a0b7dd8 CR3: 00000001065ce000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 ext4_es_remove_extent+0x187/0x230
 mpage_release_unused_pages+0x3af/0x470
 ext4_writepages+0xb9b/0x1160
 do_writepages+0xbb/0x1e0
 __filemap_fdatawrite_range+0x1b1/0x1f0
 file_write_and_wait_range+0x80/0xe0
 ext4_sync_file+0x13d/0x800
 vfs_fsync_range+0x75/0x140
 do_fsync+0x4d/0x90
 __x64_sys_fsync+0x1d/0x30
 do_syscall_64+0x33/0x40
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Above issue may happens as follows:
	process1                        process2
ext4_da_write_begin
  ext4_da_reserve_space
    ext4_es_insert_delayed_block[1/1]
                                    ext4_da_write_begin
				      ext4_es_insert_delayed_block[0/1]
ext4_writepages
  ****Delayed block allocation failed****
  mpage_release_unused_pages
    ext4_es_remove_extent[1/1]
      ext4_da_release_space [reserved 0]

ext4_da_write_begin
  ext4_es_scan_clu(inode, &ext4_es_is_delonly, lblk)
   ->As there exist [0, 1] extent, so will return true
                                   ext4_writepages
				   ****Delayed block allocation failed****
                                     mpage_release_unused_pages
				       ext4_es_remove_extent[0/1]
				         ext4_da_release_space [reserved 1]
					   ei->i_reserved_data_blocks [1->0]

  ext4_es_insert_delayed_block[1/1]

ext4_writepages
  ****Delayed block allocation failed****
  mpage_release_unused_pages
  ext4_es_remove_extent[1/1]
   ext4_da_release_space [reserved 1]
    ei->i_reserved_data_blocks[0, -1]
    ->As ei->i_reserved_data_blocks already is zero but to_free is 1,
    will trigger warning.

To solve above issue, introduce i_clu_lock to protect insert delayed
block and remove block under cluster delay allocate mode.

Signed-off-by: Ye Bin <yebin10@huawei.com>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>