Merge tag 'erofs-for-6.15-rc6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs

Pull erofs fixes from Gao Xiang:

 - Add a new reviewer, Hongbo Li, for better community development

 - Fix an I/O hang out of file-backed mounts

 - Address a rare data corruption caused by concurrent I/Os on the same
   deduplicated compressed data

 - Minor cleanup

* tag 'erofs-for-6.15-rc6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs:
  erofs: ensure the extra temporary copy is valid for shortened bvecs
  erofs: remove unused enum type
  fs/erofs/fileio: call erofs_onlinefolio_split() after bio_add_folio()
  MAINTAINERS: erofs: add myself as reviewer

Author: torvalds

MAINTAINERS

@@ -8727,6 +8727,7 @@ M:	Chao Yu <chao@kernel.org>
 R:	Yue Hu <zbestahu@gmail.com>
 R:	Jeffle Xu <jefflexu@linux.alibaba.com>
 R:	Sandeep Dhavale <dhavale@google.com>
+R:	Hongbo Li <lihongbo22@huawei.com>
 L:	linux-erofs@lists.ozlabs.org
 S:	Maintained
 W:	https://erofs.docs.kernel.org

fs/erofs/fileio.c

@@ -150,10 +150,10 @@ static int erofs_fileio_scan_folio(struct erofs_fileio *io, struct folio *folio)
 				io->rq->bio.bi_iter.bi_sector = io->dev.m_pa >> 9;
 				attached = 0;
 			}
-			if (!attached++)
-				erofs_onlinefolio_split(folio);
 			if (!bio_add_folio(&io->rq->bio, folio, len, cur))
 				goto io_retry;
+			if (!attached++)
+				erofs_onlinefolio_split(folio);
 			io->dev.m_pa += len;
 		}
 		cur += len;

fs/erofs/super.c

@@ -357,7 +357,6 @@ static void erofs_default_options(struct erofs_sb_info *sbi)
 enum {
 	Opt_user_xattr, Opt_acl, Opt_cache_strategy, Opt_dax, Opt_dax_enum,
 	Opt_device, Opt_fsid, Opt_domain_id, Opt_directio,
-	Opt_err
 };
 
 static const struct constant_table erofs_param_cache_strategy[] = {

fs/erofs/zdata.c

@@ -79,9 +79,6 @@ struct z_erofs_pcluster {
 	/* L: whether partial decompression or not */
 	bool partial;
 
-	/* L: indicate several pageofs_outs or not */
-	bool multibases;
-
 	/* L: whether extra buffer allocations are best-effort */
 	bool besteffort;
 
@@ -1046,8 +1043,6 @@ static int z_erofs_scan_folio(struct z_erofs_frontend *f,
 				break;
 
 			erofs_onlinefolio_split(folio);
-			if (f->pcl->pageofs_out != (map->m_la & ~PAGE_MASK))
-				f->pcl->multibases = true;
 			if (f->pcl->length < offset + end - map->m_la) {
 				f->pcl->length = offset + end - map->m_la;
 				f->pcl->pageofs_out = map->m_la & ~PAGE_MASK;
@@ -1093,7 +1088,6 @@ struct z_erofs_backend {
 	struct page *onstack_pages[Z_EROFS_ONSTACK_PAGES];
 	struct super_block *sb;
 	struct z_erofs_pcluster *pcl;
-
 	/* pages with the longest decompressed length for deduplication */
 	struct page **decompressed_pages;
 	/* pages to keep the compressed data */
@@ -1102,6 +1096,8 @@ struct z_erofs_backend {
 	struct list_head decompressed_secondary_bvecs;
 	struct page **pagepool;
 	unsigned int onstack_used, nr_pages;
+	/* indicate if temporary copies should be preserved for later use */
+	bool keepxcpy;
 };
 
 struct z_erofs_bvec_item {
@@ -1112,18 +1108,20 @@ struct z_erofs_bvec_item {
 static void z_erofs_do_decompressed_bvec(struct z_erofs_backend *be,
 					 struct z_erofs_bvec *bvec)
 {
+	int poff = bvec->offset + be->pcl->pageofs_out;
 	struct z_erofs_bvec_item *item;
-	unsigned int pgnr;
-
-	if (!((bvec->offset + be->pcl->pageofs_out) & ~PAGE_MASK) &&
-	    (bvec->end == PAGE_SIZE ||
-	     bvec->offset + bvec->end == be->pcl->length)) {
-		pgnr = (bvec->offset + be->pcl->pageofs_out) >> PAGE_SHIFT;
-		DBG_BUGON(pgnr >= be->nr_pages);
-		if (!be->decompressed_pages[pgnr]) {
-			be->decompressed_pages[pgnr] = bvec->page;
+	struct page **page;
+
+	if (!(poff & ~PAGE_MASK) && (bvec->end == PAGE_SIZE ||
+			bvec->offset + bvec->end == be->pcl->length)) {
+		DBG_BUGON((poff >> PAGE_SHIFT) >= be->nr_pages);
+		page = be->decompressed_pages + (poff >> PAGE_SHIFT);
+		if (!*page) {
+			*page = bvec->page;
 			return;
 		}
+	} else {
+		be->keepxcpy = true;
 	}
 
 	/* (cold path) one pcluster is requested multiple times */
@@ -1289,7 +1287,7 @@ static int z_erofs_decompress_pcluster(struct z_erofs_backend *be, int err)
 					.alg = pcl->algorithmformat,
 					.inplace_io = overlapped,
 					.partial_decoding = pcl->partial,
-					.fillgaps = pcl->multibases,
+					.fillgaps = be->keepxcpy,
 					.gfp = pcl->besteffort ? GFP_KERNEL :
 						GFP_NOWAIT | __GFP_NORETRY
 				 }, be->pagepool);
@@ -1346,7 +1344,6 @@ static int z_erofs_decompress_pcluster(struct z_erofs_backend *be, int err)
 
 	pcl->length = 0;
 	pcl->partial = true;
-	pcl->multibases = false;
 	pcl->besteffort = false;
 	pcl->bvset.nextpage = NULL;
 	pcl->vcnt = 0;