diff options
author | Gao Xiang <hsiangkao@linux.alibaba.com> | 2022-09-23 04:49:15 +0300 |
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committer | Gao Xiang <hsiangkao@linux.alibaba.com> | 2022-09-26 18:55:43 +0300 |
commit | 5c2a64252c5dc4cfe78e5b2a531c118894e3d155 (patch) | |
tree | 356748bce348364c288493b9eeb9de8994b1a95e /fs/erofs/zmap.c | |
parent | b15b2e307c3a1970d92da77a3ef57ee53d119d8e (diff) | |
download | linux-5c2a64252c5dc4cfe78e5b2a531c118894e3d155.tar.xz |
erofs: introduce partial-referenced pclusters
Due to deduplication for compressed data, pclusters can be partially
referenced with their prefixes.
Together with the user-space implementation, it enables EROFS
variable-length global compressed data deduplication with rolling
hash.
Link: https://lore.kernel.org/r/20220923014915.4362-1-hsiangkao@linux.alibaba.com
Reviewed-by: Yue Hu <huyue2@coolpad.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Diffstat (limited to 'fs/erofs/zmap.c')
-rw-r--r-- | fs/erofs/zmap.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/fs/erofs/zmap.c b/fs/erofs/zmap.c index d1723910251c..ccdddb755be8 100644 --- a/fs/erofs/zmap.c +++ b/fs/erofs/zmap.c @@ -163,6 +163,7 @@ struct z_erofs_maprecorder { u16 delta[2]; erofs_blk_t pblk, compressedblks; erofs_off_t nextpackoff; + bool partialref; }; static int z_erofs_reload_indexes(struct z_erofs_maprecorder *m, @@ -221,6 +222,8 @@ static int legacy_load_cluster_from_disk(struct z_erofs_maprecorder *m, case Z_EROFS_VLE_CLUSTER_TYPE_PLAIN: case Z_EROFS_VLE_CLUSTER_TYPE_HEAD1: case Z_EROFS_VLE_CLUSTER_TYPE_HEAD2: + if (advise & Z_EROFS_VLE_DI_PARTIAL_REF) + m->partialref = true; m->clusterofs = le16_to_cpu(di->di_clusterofs); m->pblk = le32_to_cpu(di->di_u.blkaddr); break; @@ -684,7 +687,8 @@ static int z_erofs_do_map_blocks(struct inode *inode, err = -EOPNOTSUPP; goto unmap_out; } - + if (m.partialref) + map->m_flags |= EROFS_MAP_PARTIAL_REF; map->m_llen = end - map->m_la; if (flags & EROFS_GET_BLOCKS_FINDTAIL) { |