Commit b7710262 authored by Gao Xiang's avatar Gao Xiang
Browse files

erofs: simplify tail inline pcluster handling 

Use `z_idata_size != 0` to indicate that ztailpacking is enabled.
`Z_EROFS_ADVISE_INLINE_PCLUSTER` cannot be ignored, as `h_idata_size`
could be non-zero prior to erofs-utils 1.6 [1].

Additionally, merge `z_idataoff` and `z_fragmentoff` since these two
features are mutually exclusive for a given inode.

[1] https://git.kernel.org/xiang/erofs-utils/c/547bea3cb71a


Reviewed-by: default avatarChao Yu <chao@kernel.org>
Signed-off-by: default avatarGao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20250225114038.3259726-1-hsiangkao@linux.alibaba.com
parent 57945027

fs/erofs/internal.h

+2 −7
Original line number Diff line number Diff line
@@ -263,13 +263,8 @@ struct erofs_inode { 
			unsigned char  z_algorithmtype[2];

			unsigned char  z_logical_clusterbits;

			unsigned long  z_tailextent_headlcn;

			union {

				struct {

					erofs_off_t    z_idataoff;

					unsigned short z_idata_size;

				};

			erofs_off_t    z_fragmentoff;

			};

			unsigned short z_idata_size;

		};

#endif	/* CONFIG_EROFS_FS_ZIP */

	};

fs/erofs/zmap.c

+10 −10
Original line number Diff line number Diff line
@@ -395,8 +395,8 @@ 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);

	bool ztailpacking = vi->z_advise & Z_EROFS_ADVISE_INLINE_PCLUSTER;

	bool fragment = vi->z_advise & Z_EROFS_ADVISE_FRAGMENT_PCLUSTER;

	bool ztailpacking = vi->z_idata_size;

	struct z_erofs_maprecorder m = {

		.inode = inode,

		.map = map,
@@ -415,9 +415,8 @@ static int z_erofs_do_map_blocks(struct inode *inode, 
	if (err)

		goto unmap_out;



	if (ztailpacking && (flags & EROFS_GET_BLOCKS_FINDTAIL))

		vi->z_idataoff = m.nextpackoff;



	if ((flags & EROFS_GET_BLOCKS_FINDTAIL) && ztailpacking)

		vi->z_fragmentoff = m.nextpackoff;

	map->m_flags = EROFS_MAP_MAPPED | EROFS_MAP_ENCODED;

	end = (m.lcn + 1ULL) << lclusterbits;
@@ -472,7 +471,7 @@ static int z_erofs_do_map_blocks(struct inode *inode, 
	}

	if (ztailpacking && m.lcn == vi->z_tailextent_headlcn) {

		map->m_flags |= EROFS_MAP_META;

		map->m_pa = vi->z_idataoff;

		map->m_pa = vi->z_fragmentoff;

		map->m_plen = vi->z_idata_size;

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

		map->m_flags |= EROFS_MAP_FRAGMENT;
@@ -565,6 +564,10 @@ static int z_erofs_fill_inode_lazy(struct inode *inode) 
	vi->z_advise = le16_to_cpu(h->h_advise);

	vi->z_algorithmtype[0] = h->h_algorithmtype & 15;

	vi->z_algorithmtype[1] = h->h_algorithmtype >> 4;

	if (vi->z_advise & Z_EROFS_ADVISE_FRAGMENT_PCLUSTER)

		vi->z_fragmentoff = le32_to_cpu(h->h_fragmentoff);

	else if (vi->z_advise & Z_EROFS_ADVISE_INLINE_PCLUSTER)

		vi->z_idata_size = le16_to_cpu(h->h_idata_size);



	headnr = 0;

	if (vi->z_algorithmtype[0] >= Z_EROFS_COMPRESSION_MAX ||
@@ -593,18 +596,16 @@ static int z_erofs_fill_inode_lazy(struct inode *inode) 
		goto out_put_metabuf;

	}



	if (vi->z_advise & Z_EROFS_ADVISE_INLINE_PCLUSTER) {

	if (vi->z_idata_size) {

		struct erofs_map_blocks map = {

			.buf = __EROFS_BUF_INITIALIZER

		};



		vi->z_idata_size = le16_to_cpu(h->h_idata_size);

		err = z_erofs_do_map_blocks(inode, &map,

					    EROFS_GET_BLOCKS_FINDTAIL);

		erofs_put_metabuf(&map.buf);



		if (!map.m_plen ||

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

		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;
@@ -619,7 +620,6 @@ static int z_erofs_fill_inode_lazy(struct inode *inode) 
			.buf = __EROFS_BUF_INITIALIZER

		};



		vi->z_fragmentoff = le32_to_cpu(h->h_fragmentoff);

		err = z_erofs_do_map_blocks(inode, &map,

					    EROFS_GET_BLOCKS_FINDTAIL);

		erofs_put_metabuf(&map.buf);