1 files changed, 33 insertions, 28 deletions

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index a59ab7b9aea0..355ea88d5c5f 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -3314,6 +3314,30 @@ int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_device
 	 */
 	fs_info->compress_type = BTRFS_COMPRESS_ZLIB;
 
+	/*
+	 * Flag our filesystem as having big metadata blocks if they are bigger
+	 * than the page size.
+	 */
+	if (btrfs_super_nodesize(disk_super) > PAGE_SIZE) {
+		if (!(features & BTRFS_FEATURE_INCOMPAT_BIG_METADATA))
+			btrfs_info(fs_info,
+				"flagging fs with big metadata feature");
+		features |= BTRFS_FEATURE_INCOMPAT_BIG_METADATA;
+	}
+
+	/* Set up fs_info before parsing mount options */
+	nodesize = btrfs_super_nodesize(disk_super);
+	sectorsize = btrfs_super_sectorsize(disk_super);
+	stripesize = sectorsize;
+	fs_info->dirty_metadata_batch = nodesize * (1 + ilog2(nr_cpu_ids));
+	fs_info->delalloc_batch = sectorsize * 512 * (1 + ilog2(nr_cpu_ids));
+
+	fs_info->nodesize = nodesize;
+	fs_info->sectorsize = sectorsize;
+	fs_info->sectorsize_bits = ilog2(sectorsize);
+	fs_info->csums_per_leaf = BTRFS_MAX_ITEM_SIZE(fs_info) / fs_info->csum_size;
+	fs_info->stripesize = stripesize;
+
 	ret = btrfs_parse_options(fs_info, options, sb->s_flags);
 	if (ret) {
 		err = ret;
@@ -3341,30 +3365,6 @@ int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_device
 		btrfs_info(fs_info, "has skinny extents");
 
 	/*
-	 * flag our filesystem as having big metadata blocks if
-	 * they are bigger than the page size
-	 */
-	if (btrfs_super_nodesize(disk_super) > PAGE_SIZE) {
-		if (!(features & BTRFS_FEATURE_INCOMPAT_BIG_METADATA))
-			btrfs_info(fs_info,
-				"flagging fs with big metadata feature");
-		features |= BTRFS_FEATURE_INCOMPAT_BIG_METADATA;
-	}
-
-	nodesize = btrfs_super_nodesize(disk_super);
-	sectorsize = btrfs_super_sectorsize(disk_super);
-	stripesize = sectorsize;
-	fs_info->dirty_metadata_batch = nodesize * (1 + ilog2(nr_cpu_ids));
-	fs_info->delalloc_batch = sectorsize * 512 * (1 + ilog2(nr_cpu_ids));
-
-	/* Cache block sizes */
-	fs_info->nodesize = nodesize;
-	fs_info->sectorsize = sectorsize;
-	fs_info->sectorsize_bits = ilog2(sectorsize);
-	fs_info->csums_per_leaf = BTRFS_MAX_ITEM_SIZE(fs_info) / fs_info->csum_size;
-	fs_info->stripesize = stripesize;
-
-	/*
 	 * mixed block groups end up with duplicate but slightly offset
 	 * extent buffers for the same range.  It leads to corruptions
 	 */
@@ -3392,11 +3392,16 @@ int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_device
 		goto fail_alloc;
 	}
 
-	/* For 4K sector size support, it's only read-only */
-	if (PAGE_SIZE == SZ_64K && sectorsize == SZ_4K) {
-		if (!sb_rdonly(sb) || btrfs_super_log_root(disk_super)) {
+	if (sectorsize != PAGE_SIZE) {
+		btrfs_warn(fs_info,
+		"read-write for sector size %u with page size %lu is experimental",
+			   sectorsize, PAGE_SIZE);
+	}
+	if (sectorsize != PAGE_SIZE) {
+		if (btrfs_super_incompat_flags(fs_info->super_copy) &
+			BTRFS_FEATURE_INCOMPAT_RAID56) {
 			btrfs_err(fs_info,
-	"subpage sectorsize %u only supported read-only for page size %lu",
+		"RAID56 is not yet supported for sector size %u with page size %lu",
 				sectorsize, PAGE_SIZE);
 			err = -EINVAL;
 			goto fail_alloc;