[PATCH 6.1 107/127] ext2: Drop fragment support

Greg Kroah-Hartman
2023-08-09T10:57:24Z

From: Jan Kara <jack@suse.cz>

commit 404615d7f1dcd4cca200e9a7a9df3a1dcae1dd62 upstream.

Ext2 has fields in superblock reserved for subblock allocation support.
However that never landed. Drop the many years dead code.

Reported-by: syzbot+af5e10f73dbff48f70af@syzkaller.appspotmail.com
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/ext2/ext2.h | 12 ------------
fs/ext2/super.c | 23 ++++-------------------
2 files changed, 4 insertions(+), 31 deletions(-)

--- a/fs/ext2/ext2.h
+++ b/fs/ext2/ext2.h
@@ -70,10 +70,7 @@ struct mb_cache;
* second extended-fs super-block data in memory
*/
struct ext2_sb_info {
- unsigned long s_frag_size; /* Size of a fragment in bytes */
- unsigned long s_frags_per_block;/* Number of fragments per block */
unsigned long s_inodes_per_block;/* Number of inodes per block */
- unsigned long s_frags_per_group;/* Number of fragments in a group */
unsigned long s_blocks_per_group;/* Number of blocks in a group */
unsigned long s_inodes_per_group;/* Number of inodes in a group */
unsigned long s_itb_per_group; /* Number of inode table blocks per group */
@@ -189,15 +186,6 @@ static inline struct ext2_sb_info *EXT2_
#define EXT2_FIRST_INO(s) (EXT2_SB(s)->s_first_ino)

/*
- * Macro-instructions used to manage fragments
- */
-#define EXT2_MIN_FRAG_SIZE 1024
-#define EXT2_MAX_FRAG_SIZE 4096
-#define EXT2_MIN_FRAG_LOG_SIZE 10
-#define EXT2_FRAG_SIZE(s) (EXT2_SB(s)->s_frag_size)
-#define EXT2_FRAGS_PER_BLOCK(s) (EXT2_SB(s)->s_frags_per_block)
-
-/*
* Structure of a blocks group descriptor
*/
struct ext2_group_desc
--- a/fs/ext2/super.c
+++ b/fs/ext2/super.c
@@ -668,10 +668,9 @@ static int ext2_setup_super (struct supe
es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
le16_add_cpu(&es->s_mnt_count, 1);
if (test_opt (sb, DEBUG))
- ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, fs=%lu, gc=%lu, "
+ ext2_msg(sb, KERN_INFO, "%s, %s, bs=%lu, gc=%lu, "
"bpg=%lu, ipg=%lu, mo=%04lx]",
EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
- sbi->s_frag_size,
sbi->s_groups_count,
EXT2_BLOCKS_PER_GROUP(sb),
EXT2_INODES_PER_GROUP(sb),
@@ -1012,14 +1011,7 @@ static int ext2_fill_super(struct super_
}
}

- sbi->s_frag_size = EXT2_MIN_FRAG_SIZE <<
- le32_to_cpu(es->s_log_frag_size);
- if (sbi->s_frag_size == 0)
- goto cantfind_ext2;
- sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size;
-
sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
- sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);

sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
@@ -1045,11 +1037,10 @@ static int ext2_fill_super(struct super_
goto failed_mount;
}

- if (sb->s_blocksize != sbi->s_frag_size) {
+ if (es->s_log_frag_size != es->s_log_block_size) {
ext2_msg(sb, KERN_ERR,
- "error: fragsize %lu != blocksize %lu"
- "(not supported yet)",
- sbi->s_frag_size, sb->s_blocksize);
+ "error: fragsize log %u != blocksize log %u",
+ le32_to_cpu(es->s_log_frag_size), sb->s_blocksize_bits);
goto failed_mount;
}

@@ -1066,12 +1057,6 @@ static int ext2_fill_super(struct super_
sbi->s_blocks_per_group, sbi->s_inodes_per_group + 3);
goto failed_mount;
}
- if (sbi->s_frags_per_group > sb->s_blocksize * 8) {
- ext2_msg(sb, KERN_ERR,
- "error: #fragments per group too big: %lu",
- sbi->s_frags_per_group);
- goto failed_mount;
- }
if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
sbi->s_inodes_per_group > sb->s_blocksize * 8) {
ext2_msg(sb, KERN_ERR,