block: remove CONFIG_LBDAF

Currently support for 64-bit sector_t and blkcnt_t is optional on 32-bit
architectures.  These types are required to support block device and/or
file sizes larger than 2 TiB, and have generally defaulted to on for
a long time.  Enabling the option only increases the i386 tinyconfig
size by 145 bytes, and many data structures already always use
64-bit values for their in-core and on-disk data structures anyway,
so there should not be a large change in dynamic memory usage either.

Dropping this option removes a somewhat weird non-default config that
has cause various bugs or compiler warnings when actually used.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 7 insertions, 25 deletions

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 6ed4eb81e674..d10e9e724bdd 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -2706,13 +2706,9 @@ static loff_t ext4_max_size(int blkbits, int has_huge_files)
 	loff_t res;
 	loff_t upper_limit = MAX_LFS_FILESIZE;
 
-	/* small i_blocks in vfs inode? */
-	if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
-		/*
-		 * CONFIG_LBDAF is not enabled implies the inode
-		 * i_block represent total blocks in 512 bytes
-		 * 32 == size of vfs inode i_blocks * 8
-		 */
+	BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
+
+	if (!has_huge_files) {
 		upper_limit = (1LL << 32) - 1;
 
 		/* total blocks in file system block size */
@@ -2753,11 +2749,11 @@ static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
 	 * number of 512-byte sectors of the file.
 	 */
 
-	if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
+	if (!has_huge_files) {
 		/*
-		 * !has_huge_files or CONFIG_LBDAF not enabled implies that
-		 * the inode i_block field represents total file blocks in
-		 * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
+		 * !has_huge_files or implies that the inode i_block field
+		 * represents total file blocks in 2^32 512-byte sectors ==
+		 * size of vfs inode i_blocks * 8
 		 */
 		upper_limit = (1LL << 32) - 1;
 
@@ -2897,18 +2893,6 @@ static int ext4_feature_set_ok(struct super_block *sb, int readonly)
 				~EXT4_FEATURE_RO_COMPAT_SUPP));
 		return 0;
 	}
-	/*
-	 * Large file size enabled file system can only be mounted
-	 * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
-	 */
-	if (ext4_has_feature_huge_file(sb)) {
-		if (sizeof(blkcnt_t) < sizeof(u64)) {
-			ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
-				 "cannot be mounted RDWR without "
-				 "CONFIG_LBDAF");
-			return 0;
-		}
-	}
 	if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
 		ext4_msg(sb, KERN_ERR,
 			 "Can't support bigalloc feature without "
@@ -4057,8 +4041,6 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
 	if (err) {
 		ext4_msg(sb, KERN_ERR, "filesystem"
 			 " too large to mount safely on this system");
-		if (sizeof(sector_t) < 8)
-			ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
 		goto failed_mount;
 	}