Merge tag 'erofs-for-6.1-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs

Pull erofs fixes from Gao Xiang:

 - Fix invalid unmapped accesses when initializing compressed inodes

 - Fix up very rare hung on page lock after enabling compressed data
   deduplication

 - Fix up inplace decompression success rate

 - Take s_inode_list_lock to protect sb->s_inodes for fscache shared
   domain

* tag 'erofs-for-6.1-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs:
  erofs: protect s_inodes with s_inode_list_lock for fscache
  erofs: fix up inplace decompression success rate
  erofs: shouldn't churn the mapping page for duplicated copies
  erofs: fix illegal unmapped accesses in z_erofs_fill_inode_lazy()

Author: torvalds

fs/erofs/fscache.c

@@ -590,14 +590,17 @@ struct erofs_fscache *erofs_domain_register_cookie(struct super_block *sb,
 	struct super_block *psb = erofs_pseudo_mnt->mnt_sb;
 
 	mutex_lock(&erofs_domain_cookies_lock);
+	spin_lock(&psb->s_inode_list_lock);
 	list_for_each_entry(inode, &psb->s_inodes, i_sb_list) {
 		ctx = inode->i_private;
 		if (!ctx || ctx->domain != domain || strcmp(ctx->name, name))
 			continue;
 		igrab(inode);
+		spin_unlock(&psb->s_inode_list_lock);
 		mutex_unlock(&erofs_domain_cookies_lock);
 		return ctx;
 	}
+	spin_unlock(&psb->s_inode_list_lock);
 	ctx = erofs_fscache_domain_init_cookie(sb, name, need_inode);
 	mutex_unlock(&erofs_domain_cookies_lock);
 	return ctx;

fs/erofs/zdata.c

@@ -813,15 +813,14 @@ static int z_erofs_do_read_page(struct z_erofs_decompress_frontend *fe,
 	++spiltted;
 	if (fe->pcl->pageofs_out != (map->m_la & ~PAGE_MASK))
 		fe->pcl->multibases = true;
-
-	if ((map->m_flags & EROFS_MAP_FULL_MAPPED) &&
-	    !(map->m_flags & EROFS_MAP_PARTIAL_REF) &&
-	    fe->pcl->length == map->m_llen)
-		fe->pcl->partial = false;
 	if (fe->pcl->length < offset + end - map->m_la) {
 		fe->pcl->length = offset + end - map->m_la;
 		fe->pcl->pageofs_out = map->m_la & ~PAGE_MASK;
 	}
+	if ((map->m_flags & EROFS_MAP_FULL_MAPPED) &&
+	    !(map->m_flags & EROFS_MAP_PARTIAL_REF) &&
+	    fe->pcl->length == map->m_llen)
+		fe->pcl->partial = false;
 next_part:
 	/* shorten the remaining extent to update progress */
 	map->m_llen = offset + cur - map->m_la;
@@ -888,15 +887,13 @@ static void z_erofs_do_decompressed_bvec(struct z_erofs_decompress_backend *be,
 
 	if (!((bvec->offset + be->pcl->pageofs_out) & ~PAGE_MASK)) {
 		unsigned int pgnr;
-		struct page *oldpage;
 
 		pgnr = (bvec->offset + be->pcl->pageofs_out) >> PAGE_SHIFT;
 		DBG_BUGON(pgnr >= be->nr_pages);
-		oldpage = be->decompressed_pages[pgnr];
-		be->decompressed_pages[pgnr] = bvec->page;
-
-		if (!oldpage)
+		if (!be->decompressed_pages[pgnr]) {
+			be->decompressed_pages[pgnr] = bvec->page;
 			return;
+		}
 	}
 
 	/* (cold path) one pcluster is requested multiple times */

fs/erofs/zdata.h

@@ -126,10 +126,10 @@ static inline unsigned int z_erofs_pclusterpages(struct z_erofs_pcluster *pcl)
 }
 
 /*
- * bit 31: I/O error occurred on this page
- * bit 0 - 30: remaining parts to complete this page
+ * bit 30: I/O error occurred on this page
+ * bit 0 - 29: remaining parts to complete this page
  */
-#define Z_EROFS_PAGE_EIO			(1 << 31)
+#define Z_EROFS_PAGE_EIO			(1 << 30)
 
 static inline void z_erofs_onlinepage_init(struct page *page)
 {

fs/erofs/zmap.c

@@ -57,8 +57,7 @@ static int z_erofs_fill_inode_lazy(struct inode *inode)
 
 	pos = ALIGN(iloc(EROFS_SB(sb), vi->nid) + vi->inode_isize +
 		    vi->xattr_isize, 8);
-	kaddr = erofs_read_metabuf(&buf, sb, erofs_blknr(pos),
-				   EROFS_KMAP_ATOMIC);
+	kaddr = erofs_read_metabuf(&buf, sb, erofs_blknr(pos), EROFS_KMAP);
 	if (IS_ERR(kaddr)) {
 		err = PTR_ERR(kaddr);
 		goto out_unlock;
@@ -73,7 +72,7 @@ static int z_erofs_fill_inode_lazy(struct inode *inode)
 		vi->z_advise = Z_EROFS_ADVISE_FRAGMENT_PCLUSTER;
 		vi->z_fragmentoff = le64_to_cpu(*(__le64 *)h) ^ (1ULL << 63);
 		vi->z_tailextent_headlcn = 0;
-		goto unmap_done;
+		goto done;
 	}
 	vi->z_advise = le16_to_cpu(h->h_advise);
 	vi->z_algorithmtype[0] = h->h_algorithmtype & 15;
@@ -85,7 +84,7 @@ static int z_erofs_fill_inode_lazy(struct inode *inode)
 		erofs_err(sb, "unknown HEAD%u format %u for nid %llu, please upgrade kernel",
 			  headnr + 1, vi->z_algorithmtype[headnr], vi->nid);
 		err = -EOPNOTSUPP;
-		goto unmap_done;
+		goto out_put_metabuf;
 	}
 
 	vi->z_logical_clusterbits = LOG_BLOCK_SIZE + (h->h_clusterbits & 7);
@@ -95,20 +94,16 @@ static int z_erofs_fill_inode_lazy(struct inode *inode)
 		erofs_err(sb, "per-inode big pcluster without sb feature for nid %llu",
 			  vi->nid);
 		err = -EFSCORRUPTED;
-		goto unmap_done;
+		goto out_put_metabuf;
 	}
 	if (vi->datalayout == EROFS_INODE_FLAT_COMPRESSION &&
 	    !(vi->z_advise & Z_EROFS_ADVISE_BIG_PCLUSTER_1) ^
 	    !(vi->z_advise & Z_EROFS_ADVISE_BIG_PCLUSTER_2)) {
 		erofs_err(sb, "big pcluster head1/2 of compact indexes should be consistent for nid %llu",
 			  vi->nid);
 		err = -EFSCORRUPTED;
-		goto unmap_done;
+		goto out_put_metabuf;
 	}
-unmap_done:
-	erofs_put_metabuf(&buf);
-	if (err)
-		goto out_unlock;
 
 	if (vi->z_advise & Z_EROFS_ADVISE_INLINE_PCLUSTER) {
 		struct erofs_map_blocks map = {
@@ -127,7 +122,7 @@ static int z_erofs_fill_inode_lazy(struct inode *inode)
 			err = -EFSCORRUPTED;
 		}
 		if (err < 0)
-			goto out_unlock;
+			goto out_put_metabuf;
 	}
 
 	if (vi->z_advise & Z_EROFS_ADVISE_FRAGMENT_PCLUSTER &&
@@ -141,11 +136,14 @@ static int z_erofs_fill_inode_lazy(struct inode *inode)
 					    EROFS_GET_BLOCKS_FINDTAIL);
 		erofs_put_metabuf(&map.buf);
 		if (err < 0)
-			goto out_unlock;
+			goto out_put_metabuf;
 	}
+done:
 	/* paired with smp_mb() at the beginning of the function */
 	smp_mb();
 	set_bit(EROFS_I_Z_INITED_BIT, &vi->flags);
+out_put_metabuf:
+	erofs_put_metabuf(&buf);
 out_unlock:
 	clear_and_wake_up_bit(EROFS_I_BL_Z_BIT, &vi->flags);
 	return err;