Commit 8241fdd3 authored by Gao Xiang's avatar Gao Xiang
Browse files

erofs: clean up zmap.c 



Several trivial cleanups which aren't quite necessary to split:

 - Rename lcluster load functions as well as justify full indexes
   since they are typically used for global deduplication for
   compressed data;

 - Avoid unnecessary lines, comments for simplicity.

No logic changes.

Reviewed-by: default avatarGuo Xuenan <guoxuenan@huaweicloud.com>
Reviewed-by: default avatarYue Hu <huyue2@coolpad.com>
Signed-off-by: default avatarGao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20230615064421.103178-1-hsiangkao@linux.alibaba.com
parent 19905955

fs/erofs/zmap.c

+29 −40
Original line number Diff line number Diff line
@@ -22,7 +22,7 @@ struct z_erofs_maprecorder { 
	bool partialref;

};



static int legacy_load_cluster_from_disk(struct z_erofs_maprecorder *m,

static int z_erofs_load_full_lcluster(struct z_erofs_maprecorder *m,

				      unsigned long lcn)

{

	struct inode *const inode = m->inode;
@@ -226,7 +226,7 @@ static int unpack_compacted_index(struct z_erofs_maprecorder *m, 
	return 0;

}



static int compacted_load_cluster_from_disk(struct z_erofs_maprecorder *m,

static int z_erofs_load_compact_lcluster(struct z_erofs_maprecorder *m,

					 unsigned long lcn, bool lookahead)

{

	struct inode *const inode = m->inode;
@@ -277,23 +277,23 @@ static int compacted_load_cluster_from_disk(struct z_erofs_maprecorder *m, 
	return unpack_compacted_index(m, amortizedshift, pos, lookahead);

}



static int z_erofs_load_cluster_from_disk(struct z_erofs_maprecorder *m,

static int z_erofs_load_lcluster_from_disk(struct z_erofs_maprecorder *m,

					   unsigned int lcn, bool lookahead)

{

	const unsigned int datamode = EROFS_I(m->inode)->datalayout;



	if (datamode == EROFS_INODE_COMPRESSED_FULL)

		return legacy_load_cluster_from_disk(m, lcn);



	if (datamode == EROFS_INODE_COMPRESSED_COMPACT)

		return compacted_load_cluster_from_disk(m, lcn, lookahead);



	switch (EROFS_I(m->inode)->datalayout) {

	case EROFS_INODE_COMPRESSED_FULL:

		return z_erofs_load_full_lcluster(m, lcn);

	case EROFS_INODE_COMPRESSED_COMPACT:

		return z_erofs_load_compact_lcluster(m, lcn, lookahead);

	default:

		return -EINVAL;

	}

}



static int z_erofs_extent_lookback(struct z_erofs_maprecorder *m,

				   unsigned int lookback_distance)

{

	struct super_block *sb = m->inode->i_sb;

	struct erofs_inode *const vi = EROFS_I(m->inode);

	const unsigned int lclusterbits = vi->z_logical_clusterbits;
@@ -301,21 +301,15 @@ static int z_erofs_extent_lookback(struct z_erofs_maprecorder *m, 
		unsigned long lcn = m->lcn - lookback_distance;

		int err;



		/* load extent head logical cluster if needed */

		err = z_erofs_load_cluster_from_disk(m, lcn, false);

		err = z_erofs_load_lcluster_from_disk(m, lcn, false);

		if (err)

			return err;



		switch (m->type) {

		case Z_EROFS_LCLUSTER_TYPE_NONHEAD:

			if (!m->delta[0]) {

				erofs_err(m->inode->i_sb,

					  "invalid lookback distance 0 @ nid %llu",

					  vi->nid);

				DBG_BUGON(1);

				return -EFSCORRUPTED;

			}

			lookback_distance = m->delta[0];

			if (!lookback_distance)

				goto err_bogus;

			continue;

		case Z_EROFS_LCLUSTER_TYPE_PLAIN:

		case Z_EROFS_LCLUSTER_TYPE_HEAD1:
@@ -324,16 +318,15 @@ static int z_erofs_extent_lookback(struct z_erofs_maprecorder *m, 
			m->map->m_la = (lcn << lclusterbits) | m->clusterofs;

			return 0;

		default:

			erofs_err(m->inode->i_sb,

				  "unknown type %u @ lcn %lu of nid %llu",

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

				  m->type, lcn, vi->nid);

			DBG_BUGON(1);

			return -EOPNOTSUPP;

		}

	}



	erofs_err(m->inode->i_sb, "bogus lookback distance @ nid %llu",

		  vi->nid);

err_bogus:

	erofs_err(sb, "bogus lookback distance %u @ lcn %lu of nid %llu",

		  lookback_distance, m->lcn, vi->nid);

	DBG_BUGON(1);

	return -EFSCORRUPTED;

}
@@ -365,7 +358,7 @@ static int z_erofs_get_extent_compressedlen(struct z_erofs_maprecorder *m, 
	if (m->compressedblks)

		goto out;



	err = z_erofs_load_cluster_from_disk(m, lcn, false);

	err = z_erofs_load_lcluster_from_disk(m, lcn, false);

	if (err)

		return err;
@@ -397,9 +390,8 @@ static int z_erofs_get_extent_compressedlen(struct z_erofs_maprecorder *m, 
			break;

		fallthrough;

	default:

		erofs_err(m->inode->i_sb,

			  "cannot found CBLKCNT @ lcn %lu of nid %llu",

			  lcn, vi->nid);

		erofs_err(sb, "cannot found CBLKCNT @ lcn %lu of nid %llu", lcn,

			  vi->nid);

		DBG_BUGON(1);

		return -EFSCORRUPTED;

	}
@@ -407,9 +399,7 @@ static int z_erofs_get_extent_compressedlen(struct z_erofs_maprecorder *m, 
	map->m_plen = erofs_pos(sb, m->compressedblks);

	return 0;

err_bonus_cblkcnt:

	erofs_err(m->inode->i_sb,

		  "bogus CBLKCNT @ lcn %lu of nid %llu",

		  lcn, vi->nid);

	erofs_err(sb, "bogus CBLKCNT @ lcn %lu of nid %llu", lcn, vi->nid);

	DBG_BUGON(1);

	return -EFSCORRUPTED;

}
@@ -430,7 +420,7 @@ static int z_erofs_get_extent_decompressedlen(struct z_erofs_maprecorder *m) 
			return 0;

		}



		err = z_erofs_load_cluster_from_disk(m, lcn, true);

		err = z_erofs_load_lcluster_from_disk(m, lcn, true);

		if (err)

			return err;
@@ -477,7 +467,7 @@ static int z_erofs_do_map_blocks(struct inode *inode, 
	initial_lcn = ofs >> lclusterbits;

	endoff = ofs & ((1 << lclusterbits) - 1);



	err = z_erofs_load_cluster_from_disk(&m, initial_lcn, false);

	err = z_erofs_load_lcluster_from_disk(&m, initial_lcn, false);

	if (err)

		goto unmap_out;
@@ -535,8 +525,7 @@ static int z_erofs_do_map_blocks(struct inode *inode, 
	if (flags & EROFS_GET_BLOCKS_FINDTAIL) {

		vi->z_tailextent_headlcn = m.lcn;

		/* for non-compact indexes, fragmentoff is 64 bits */

		if (fragment &&

		    vi->datalayout == EROFS_INODE_COMPRESSED_FULL)

		if (fragment && vi->datalayout == EROFS_INODE_COMPRESSED_FULL)

			vi->z_fragmentoff |= (u64)m.pblk << 32;

	}

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