From: Chao Yu Date: Mon, 21 Jul 2025 02:02:31 +0000 (+0800) Subject: f2fs: don't break allocation when crossing contiguous sections X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=f0a7adfedcc8c7e0b13ffd11dd69bf0ac25b2cd3;p=users%2Fdwmw2%2Flinux.git f2fs: don't break allocation when crossing contiguous sections Commit 0638a3197c19 ("f2fs: avoid unused block when dio write in LFS mode") has fixed unused block issue for dio write in lfs mode. However, f2fs_map_blocks() may break and return smaller extent when last allocated block locates in the end of section, even allocator can allocate contiguous blocks across sections. Actually, for the case that allocator returns a block address which is not contiguous w/ current extent, we can record the block address in iomap->private, in the next round, skip reallocating for the last allocated block, then we can fix unused block issue, meanwhile, also, we can allocates contiguous physical blocks as much as possible for dio write in lfs mode. Testcase: - mkfs.f2fs -f /dev/vdb - mount -o mode=lfs /dev/vdb /mnt/f2fs - dd if=/dev/zero of=/mnt/f2fs/file bs=1M count=3; sync; - dd if=/dev/zero of=/mnt/f2fs/dio bs=2M count=1 oflag=direct; - umount /mnt/f2fs Before: f2fs_map_blocks: dev = (253,16), ino = 4, file offset = 0, start blkaddr = 0x0, len = 0x100, flags = 1, seg_type = 8, may_create = 1, multidevice = 0, flag = 5, err = 0 f2fs_map_blocks: dev = (253,16), ino = 4, file offset = 256, start blkaddr = 0x0, len = 0x100, flags = 1, seg_type = 8, may_create = 1, multidevice = 0, flag = 5, err = 0 f2fs_map_blocks: dev = (253,16), ino = 4, file offset = 512, start blkaddr = 0x0, len = 0x100, flags = 1, seg_type = 8, may_create = 1, multidevice = 0, flag = 5, err = 0 f2fs_map_blocks: dev = (253,16), ino = 5, file offset = 0, start blkaddr = 0x4700, len = 0x100, flags = 3, seg_type = 1, may_create = 1, multidevice = 0, flag = 3, err = 0 f2fs_map_blocks: dev = (253,16), ino = 5, file offset = 256, start blkaddr = 0x4800, len = 0x100, flags = 3, seg_type = 1, may_create = 1, multidevice = 0, flag = 3, err = 0 After: f2fs_map_blocks: dev = (253,16), ino = 4, file offset = 0, start blkaddr = 0x0, len = 0x100, flags = 1, seg_type = 8, may_create = 1, multidevice = 0, flag = 5, err = 0 f2fs_map_blocks: dev = (253,16), ino = 4, file offset = 256, start blkaddr = 0x0, len = 0x100, flags = 1, seg_type = 8, may_create = 1, multidevice = 0, flag = 5, err = 0 f2fs_map_blocks: dev = (253,16), ino = 4, file offset = 512, start blkaddr = 0x0, len = 0x100, flags = 1, seg_type = 8, may_create = 1, multidevice = 0, flag = 5, err = 0 f2fs_map_blocks: dev = (253,16), ino = 5, file offset = 0, start blkaddr = 0x4700, len = 0x200, flags = 3, seg_type = 1, may_create = 1, multidevice = 0, flag = 3, err = 0 Cc: Daejun Park Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim --- diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index 0acc25f996b3c..e11dd1431e5b5 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -1550,10 +1550,14 @@ int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map, int flag) unsigned int start_pgofs; int bidx = 0; bool is_hole; + bool lfs_dio_write; if (!maxblocks) return 0; + lfs_dio_write = (flag == F2FS_GET_BLOCK_DIO && f2fs_lfs_mode(sbi) && + map->m_may_create); + if (!map->m_may_create && f2fs_map_blocks_cached(inode, map, flag)) goto out; @@ -1600,7 +1604,7 @@ next_block: /* use out-place-update for direct IO under LFS mode */ if (map->m_may_create && (is_hole || (flag == F2FS_GET_BLOCK_DIO && f2fs_lfs_mode(sbi) && - !f2fs_is_pinned_file(inode)))) { + !f2fs_is_pinned_file(inode) && map->m_last_pblk != blkaddr))) { if (unlikely(f2fs_cp_error(sbi))) { err = -EIO; goto sync_out; @@ -1684,10 +1688,15 @@ next_block: if (map->m_multidev_dio) map->m_bdev = FDEV(bidx).bdev; + + if (lfs_dio_write) + map->m_last_pblk = NULL_ADDR; } else if (map_is_mergeable(sbi, map, blkaddr, flag, bidx, ofs)) { ofs++; map->m_len++; } else { + if (lfs_dio_write && !f2fs_is_pinned_file(inode)) + map->m_last_pblk = blkaddr; goto sync_out; } @@ -1712,14 +1721,6 @@ skip: dn.ofs_in_node = end_offset; } - if (flag == F2FS_GET_BLOCK_DIO && f2fs_lfs_mode(sbi) && - map->m_may_create) { - /* the next block to be allocated may not be contiguous. */ - if (GET_SEGOFF_FROM_SEG0(sbi, blkaddr) % BLKS_PER_SEC(sbi) == - CAP_BLKS_PER_SEC(sbi) - 1) - goto sync_out; - } - if (pgofs >= end) goto sync_out; else if (dn.ofs_in_node < end_offset) @@ -4162,7 +4163,7 @@ static int f2fs_iomap_begin(struct inode *inode, loff_t offset, loff_t length, unsigned int flags, struct iomap *iomap, struct iomap *srcmap) { - struct f2fs_map_blocks map = {}; + struct f2fs_map_blocks map = { NULL, }; pgoff_t next_pgofs = 0; int err; @@ -4171,6 +4172,10 @@ static int f2fs_iomap_begin(struct inode *inode, loff_t offset, loff_t length, map.m_next_pgofs = &next_pgofs; map.m_seg_type = f2fs_rw_hint_to_seg_type(F2FS_I_SB(inode), inode->i_write_hint); + if (flags & IOMAP_WRITE && iomap->private) { + map.m_last_pblk = (unsigned long)iomap->private; + iomap->private = NULL; + } /* * If the blocks being overwritten are already allocated, @@ -4209,6 +4214,9 @@ static int f2fs_iomap_begin(struct inode *inode, loff_t offset, loff_t length, iomap->flags |= IOMAP_F_MERGED; iomap->bdev = map.m_bdev; iomap->addr = F2FS_BLK_TO_BYTES(map.m_pblk); + + if (flags & IOMAP_WRITE && map.m_last_pblk) + iomap->private = (void *)map.m_last_pblk; } else { if (flags & IOMAP_WRITE) return -ENOTBLK; diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index dfddb66910b3f..97c1a2a3fbd7e 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -732,6 +732,7 @@ struct f2fs_map_blocks { block_t m_lblk; unsigned int m_len; unsigned int m_flags; + unsigned long m_last_pblk; /* last allocated block, only used for DIO in LFS mode */ pgoff_t *m_next_pgofs; /* point next possible non-hole pgofs */ pgoff_t *m_next_extent; /* point to next possible extent */ int m_seg_type;