Commit 540787d3 authored by Gao Xiang's avatar Gao Xiang
Browse files

erofs: clean up header parsing for ztailpacking and fragments 



Simplify the logic in z_erofs_fill_inode_lazy() by combining the
handling of ztailpacking and fragments, as they are mutually exclusive.

Note that `h->h_clusterbits >> Z_EROFS_FRAGMENT_INODE_BIT` is handled
above, so no need to duplicate the check.

Reviewed-by: default avatarChao Yu <chao@kernel.org>
Signed-off-by: default avatarGao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20250224123747.1387122-2-hsiangkao@linux.alibaba.com
parent b7710262

fs/erofs/zmap.c

+14 −25
Original line number Diff line number Diff line
@@ -394,7 +394,8 @@ static int z_erofs_get_extent_decompressedlen(struct z_erofs_maprecorder *m) 
static int z_erofs_do_map_blocks(struct inode *inode,

				 struct erofs_map_blocks *map, int flags)

{

	struct erofs_inode *const vi = EROFS_I(inode);

	struct erofs_inode *vi = EROFS_I(inode);

	struct super_block *sb = inode->i_sb;

	bool fragment = vi->z_advise & Z_EROFS_ADVISE_FRAGMENT_PCLUSTER;

	bool ztailpacking = vi->z_idata_size;

	struct z_erofs_maprecorder m = {
@@ -438,7 +439,7 @@ static int z_erofs_do_map_blocks(struct inode *inode, 
		}

		/* m.lcn should be >= 1 if endoff < m.clusterofs */

		if (!m.lcn) {

			erofs_err(inode->i_sb, "invalid logical cluster 0 at nid %llu",

			erofs_err(sb, "invalid logical cluster 0 at nid %llu",

				  vi->nid);

			err = -EFSCORRUPTED;

			goto unmap_out;
@@ -454,7 +455,7 @@ static int z_erofs_do_map_blocks(struct inode *inode, 
			goto unmap_out;

		break;

	default:

		erofs_err(inode->i_sb, "unknown type %u @ offset %llu of nid %llu",

		erofs_err(sb, "unknown type %u @ offset %llu of nid %llu",

			  m.type, ofs, vi->nid);

		err = -EOPNOTSUPP;

		goto unmap_out;
@@ -473,10 +474,16 @@ static int z_erofs_do_map_blocks(struct inode *inode, 
		map->m_flags |= EROFS_MAP_META;

		map->m_pa = vi->z_fragmentoff;

		map->m_plen = vi->z_idata_size;

		if (erofs_blkoff(sb, map->m_pa) + map->m_plen > sb->s_blocksize) {

			erofs_err(sb, "invalid tail-packing pclustersize %llu",

				  map->m_plen);

			err = -EFSCORRUPTED;

			goto unmap_out;

		}

	} else if (fragment && m.lcn == vi->z_tailextent_headlcn) {

		map->m_flags |= EROFS_MAP_FRAGMENT;

	} else {

		map->m_pa = erofs_pos(inode->i_sb, m.pblk);

		map->m_pa = erofs_pos(sb, m.pblk);

		err = z_erofs_get_extent_compressedlen(&m, initial_lcn);

		if (err)

			goto unmap_out;
@@ -495,7 +502,7 @@ static int z_erofs_do_map_blocks(struct inode *inode, 
		afmt = m.headtype == Z_EROFS_LCLUSTER_TYPE_HEAD2 ?

			vi->z_algorithmtype[1] : vi->z_algorithmtype[0];

		if (!(EROFS_I_SB(inode)->available_compr_algs & (1 << afmt))) {

			erofs_err(inode->i_sb, "inconsistent algorithmtype %u for nid %llu",

			erofs_err(sb, "inconsistent algorithmtype %u for nid %llu",

				  afmt, vi->nid);

			err = -EFSCORRUPTED;

			goto unmap_out;
@@ -596,26 +603,8 @@ static int z_erofs_fill_inode_lazy(struct inode *inode) 
		goto out_put_metabuf;

	}



	if (vi->z_idata_size) {

		struct erofs_map_blocks map = {

			.buf = __EROFS_BUF_INITIALIZER

		};



		err = z_erofs_do_map_blocks(inode, &map,

					    EROFS_GET_BLOCKS_FINDTAIL);

		erofs_put_metabuf(&map.buf);



		if (erofs_blkoff(sb, map.m_pa) + map.m_plen > sb->s_blocksize) {

			erofs_err(sb, "invalid tail-packing pclustersize %llu",

				  map.m_plen);

			err = -EFSCORRUPTED;

		}

		if (err < 0)

			goto out_put_metabuf;

	}



	if (vi->z_advise & Z_EROFS_ADVISE_FRAGMENT_PCLUSTER &&

	    !(h->h_clusterbits >> Z_EROFS_FRAGMENT_INODE_BIT)) {

	if (vi->z_idata_size ||

	    (vi->z_advise & Z_EROFS_ADVISE_FRAGMENT_PCLUSTER)) {

		struct erofs_map_blocks map = {

			.buf = __EROFS_BUF_INITIALIZER

		};