Merge tag 'erofs-for-5.4-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs

Pull erofs fixes from Gao Xiang:
 "Three patches to address regressions due to recent cleanups, mainly
  found by stress test on latest mainline kernel (no more regression out
  compared with older kernels for more than a week)

  One additional patch updates sub-entries in MAINTAINERS.

  Summary:

   - Fix error handling in erofs_read_superblock

   - Fix locking in erofs_get_meta_page

   - Fix inplace behavior due to decompression frontend cleanup

   - Update sub-entries in MAINTAINERS in order to better blame"

* tag 'erofs-for-5.4-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs:
  erofs: fix mis-inplace determination related with noio chain
  erofs: fix erofs_get_meta_page locking due to a cleanup
  MAINTAINERS: erofs: complete sub-entries for erofs
  erofs: fix return value check in erofs_read_superblock()

4 files changed, 22 insertions, 7 deletions

diff --git a/MAINTAINERS b/MAINTAINERS
index 296de2b51c832e..30a5b4028d2fc9 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6112,7 +6112,10 @@ M:	Gao Xiang <gaoxiang25@huawei.com>
 M:	Chao Yu <yuchao0@huawei.com>
 L:	linux-erofs@lists.ozlabs.org
 S:	Maintained
+T:	git git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs.git
+F:	Documentation/filesystems/erofs.txt
 F:	fs/erofs/
+F:	include/trace/events/erofs.h
 
 ERRSEQ ERROR TRACKING INFRASTRUCTURE
 M:	Jeff Layton <jlayton@kernel.org>
diff --git a/fs/erofs/data.c b/fs/erofs/data.c
index 8a9fcbd0e8ac19..fc3a8d8064f84f 100644
--- a/fs/erofs/data.c
+++ b/fs/erofs/data.c
@@ -34,11 +34,15 @@ static void erofs_readendio(struct bio *bio)
 
 struct page *erofs_get_meta_page(struct super_block *sb, erofs_blk_t blkaddr)
 {
-	struct inode *const bd_inode = sb->s_bdev->bd_inode;
-	struct address_space *const mapping = bd_inode->i_mapping;
+	struct address_space *const mapping = sb->s_bdev->bd_inode->i_mapping;
+	struct page *page;
 
-	return read_cache_page_gfp(mapping, blkaddr,
+	page = read_cache_page_gfp(mapping, blkaddr,
 				   mapping_gfp_constraint(mapping, ~__GFP_FS));
+	/* should already be PageUptodate */
+	if (!IS_ERR(page))
+		lock_page(page);
+	return page;
 }
 
 static int erofs_map_blocks_flatmode(struct inode *inode,
diff --git a/fs/erofs/super.c b/fs/erofs/super.c
index caf9a95173b0fb..0e369494f2f2c4 100644
--- a/fs/erofs/super.c
+++ b/fs/erofs/super.c
@@ -105,9 +105,9 @@ static int erofs_read_superblock(struct super_block *sb)
 	int ret;
 
 	page = read_mapping_page(sb->s_bdev->bd_inode->i_mapping, 0, NULL);
-	if (!page) {
+	if (IS_ERR(page)) {
 		erofs_err(sb, "cannot read erofs superblock");
-		return -EIO;
+		return PTR_ERR(page);
 	}
 
 	sbi = EROFS_SB(sb);
diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c
index 96e34c90f81438..fad80c97d2476f 100644
--- a/fs/erofs/zdata.c
+++ b/fs/erofs/zdata.c
@@ -575,7 +575,7 @@ static int z_erofs_do_read_page(struct z_erofs_decompress_frontend *fe,
 	struct erofs_map_blocks *const map = &fe->map;
 	struct z_erofs_collector *const clt = &fe->clt;
 	const loff_t offset = page_offset(page);
-	bool tight = (clt->mode >= COLLECT_PRIMARY_HOOKED);
+	bool tight = true;
 
 	enum z_erofs_cache_alloctype cache_strategy;
 	enum z_erofs_page_type page_type;
@@ -628,8 +628,16 @@ restart_now:
 	preload_compressed_pages(clt, MNGD_MAPPING(sbi),
 				 cache_strategy, pagepool);
 
-	tight &= (clt->mode >= COLLECT_PRIMARY_HOOKED);
 hitted:
+	/*
+	 * Ensure the current partial page belongs to this submit chain rather
+	 * than other concurrent submit chains or the noio(bypass) chain since
+	 * those chains are handled asynchronously thus the page cannot be used
+	 * for inplace I/O or pagevec (should be processed in strict order.)
+	 */
+	tight &= (clt->mode >= COLLECT_PRIMARY_HOOKED &&
+		  clt->mode != COLLECT_PRIMARY_FOLLOWED_NOINPLACE);
+
 	cur = end - min_t(unsigned int, offset + end - map->m_la, end);
 	if (!(map->m_flags & EROFS_MAP_MAPPED)) {
 		zero_user_segment(page, cur, end);