[PATCH 2/2] f2fs: support to map continuous holes or preallocated address

From: Chao Yu
Date: Mon Mar 25 2024 - 15:01:20 EST


This patch supports to map continuous holes or preallocated addresses
to improve performace of lookuping mapping info during read DIO.

[testcase 1]
xfs_io -f /mnt/f2fs/hole -c "truncate 1m" -c "fsync"
xfs_io -d /mnt/f2fs/hole -c "pread -b 1m 0 1m"

[before]
f2fs_direct_IO_enter: dev = (253,16), ino = 6 pos = 0 len = 1048576 ki_flags = 20000 ki_ioprio = 0 rw = 0
f2fs_map_blocks: dev = (253,16), ino = 6, file offset = 0, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 6, file offset = 1, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 6, file offset = 2, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 6, file offset = 3, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 6, file offset = 4, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 6, file offset = 5, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 6, file offset = 6, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 6, file offset = 7, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 6, file offset = 8, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 6, file offset = 9, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 6, file offset = 10, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 6, file offset = 11, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 6, file offset = 12, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 6, file offset = 13, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 6, file offset = 14, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 6, file offset = 15, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 6, file offset = 16, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
.....
f2fs_direct_IO_exit: dev = (253,16), ino = 6 pos = 0 len = 1048576 rw = 0 ret = 1048576

[after]
f2fs_direct_IO_enter: dev = (253,16), ino = 6 pos = 0 len = 1048576 ki_flags = 20000 ki_ioprio = 0 rw = 0
f2fs_map_blocks: dev = (253,16), ino = 6, file offset = 0, start blkaddr = 0x0, len = 0x100, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_direct_IO_exit: dev = (253,16), ino = 6 pos = 0 len = 1048576 rw = 0 ret = 1048576

[testcase 2]
xfs_io -f /mnt/f2fs/preallocated -c "falloc 0 1m" -c "fsync"
xfs_io -d /mnt/f2fs/preallocated -c "pread -b 1m 0 1m"

[before]
f2fs_direct_IO_enter: dev = (253,16), ino = 11 pos = 0 len = 1048576 ki_flags = 20000 ki_ioprio = 0 rw = 0
f2fs_map_blocks: dev = (253,16), ino = 11, file offset = 0, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 11, file offset = 1, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 11, file offset = 2, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 11, file offset = 3, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 11, file offset = 4, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 11, file offset = 5, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 11, file offset = 6, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 11, file offset = 7, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 11, file offset = 8, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 11, file offset = 9, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 11, file offset = 10, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 11, file offset = 11, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 11, file offset = 12, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 11, file offset = 13, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 11, file offset = 14, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 11, file offset = 15, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_map_blocks: dev = (253,16), ino = 11, file offset = 16, start blkaddr = 0x0, len = 0x0, flags = 0, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
.....
f2fs_direct_IO_exit: dev = (253,16), ino = 11 pos = 0 len = 1048576 rw = 0 ret = 1048576

[after]
f2fs_direct_IO_enter: dev = (253,16), ino = 11 pos = 0 len = 1048576 ki_flags = 20000 ki_ioprio = 0 rw = 0
f2fs_map_blocks: dev = (253,16), ino = 11, file offset = 0, start blkaddr = 0xffffffff, len = 0x100, flags = 4, seg_type = 1, may_create = 0, multidevice = 0, flag = 3, err = 0
f2fs_direct_IO_exit: dev = (253,16), ino = 11 pos = 0 len = 1048576 rw = 0 ret = 1048576

Signed-off-by: Chao Yu <chao@xxxxxxxxxx>
---
fs/f2fs/data.c | 29 +++++++++++++++++++++++------
1 file changed, 23 insertions(+), 6 deletions(-)

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 9c000ca4f808..47e9b1bddb9b 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -1521,6 +1521,9 @@ static bool map_is_mergeable(struct f2fs_sb_info *sbi,
return true;
if (flag == F2FS_GET_BLOCK_PRE_DIO)
return true;
+ if (flag == F2FS_GET_BLOCK_DIO &&
+ map->m_pblk == NULL_ADDR && blkaddr == NULL_ADDR)
+ return true;
return false;
}

@@ -1645,6 +1648,10 @@ int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map, int flag)
goto sync_out;
}
break;
+ case F2FS_GET_BLOCK_DIO:
+ if (map->m_next_pgofs)
+ *map->m_next_pgofs = pgofs + 1;
+ break;
default:
/* for defragment case */
if (map->m_next_pgofs)
@@ -1663,7 +1670,8 @@ int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map, int flag)
/* reserved delalloc block should be mapped for fiemap. */
if (blkaddr == NEW_ADDR)
map->m_flags |= F2FS_MAP_DELALLOC;
- map->m_flags |= F2FS_MAP_MAPPED;
+ if (flag != F2FS_GET_BLOCK_DIO || !is_hole)
+ map->m_flags |= F2FS_MAP_MAPPED;

map->m_pblk = blkaddr;
map->m_len = 1;
@@ -4192,12 +4200,13 @@ static int f2fs_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
* We should never see delalloc or compressed extents here based on
* prior flushing and checks.
*/
- if (WARN_ON_ONCE(map.m_pblk == NEW_ADDR))
- return -EINVAL;
if (WARN_ON_ONCE(map.m_pblk == COMPRESS_ADDR))
return -EINVAL;

if (map.m_flags & F2FS_MAP_MAPPED) {
+ if (WARN_ON_ONCE(map.m_pblk == NEW_ADDR))
+ return -EINVAL;
+
iomap->length = blks_to_bytes(inode, map.m_len);
iomap->type = IOMAP_MAPPED;
iomap->flags |= IOMAP_F_MERGED;
@@ -4206,9 +4215,17 @@ static int f2fs_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
} else {
if (flags & IOMAP_WRITE)
return -ENOTBLK;
- iomap->length = blks_to_bytes(inode, next_pgofs) -
- iomap->offset;
- iomap->type = IOMAP_HOLE;
+
+ if (map.m_pblk == NULL_ADDR) {
+ iomap->length = blks_to_bytes(inode, next_pgofs) -
+ iomap->offset;
+ iomap->type = IOMAP_HOLE;
+ } else if (map.m_pblk == NEW_ADDR) {
+ iomap->length = blks_to_bytes(inode, map.m_len);
+ iomap->type = IOMAP_UNWRITTEN;
+ } else {
+ f2fs_bug_on(F2FS_I_SB(inode), 1);
+ }
iomap->addr = IOMAP_NULL_ADDR;
}

--
2.40.1