Since the iomap buffered I/O path does not yet support all existing features, it cannot be used by default. Introduce 'buffered_iomap' and 'nobuffered_iomap' mount options to enable and disable the iomap buffered I/O path for regular files. Signed-off-by: Zhang Yi --- fs/ext4/ext4.h | 1 + fs/ext4/inode.c | 2 ++ fs/ext4/super.c | 7 +++++++ 3 files changed, 10 insertions(+) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 259c6e780e65..4e209c14dab9 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1288,6 +1288,7 @@ struct ext4_inode_info { * scanning in mballoc */ #define EXT4_MOUNT2_ABORT 0x00000100 /* Abort filesystem */ +#define EXT4_MOUNT2_BUFFERED_IOMAP 0x00000200 /* Use iomap for buffered I/O */ #define clear_opt(sb, opt) EXT4_SB(sb)->s_mount_opt &= \ ~EXT4_MOUNT_##opt diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index bbdd0bb3bc8b..a3d7c98309bb 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -5743,6 +5743,8 @@ void ext4_enable_buffered_iomap(struct inode *inode) { struct super_block *sb = inode->i_sb; + if (!test_opt2(sb, BUFFERED_IOMAP)) + return; if (!S_ISREG(inode->i_mode)) return; if (ext4_test_inode_flag(inode, EXT4_INODE_EA_INODE)) diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 4bb77703ffe1..d967792c7cb1 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -1701,6 +1701,7 @@ enum { Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable, Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache, Opt_no_prefetch_block_bitmaps, Opt_mb_optimize_scan, + Opt_buffered_iomap, Opt_nobuffered_iomap, Opt_errors, Opt_data, Opt_data_err, Opt_jqfmt, Opt_dax_type, #ifdef CONFIG_EXT4_DEBUG Opt_fc_debug_max_replay, Opt_fc_debug_force @@ -1839,6 +1840,8 @@ static const struct fs_parameter_spec ext4_param_specs[] = { fsparam_flag ("no_prefetch_block_bitmaps", Opt_no_prefetch_block_bitmaps), fsparam_s32 ("mb_optimize_scan", Opt_mb_optimize_scan), + fsparam_flag ("buffered_iomap", Opt_buffered_iomap), + fsparam_flag ("nobuffered_iomap", Opt_nobuffered_iomap), fsparam_string ("check", Opt_removed), /* mount option from ext2/3 */ fsparam_flag ("nocheck", Opt_removed), /* mount option from ext2/3 */ fsparam_flag ("reservation", Opt_removed), /* mount option from ext2/3 */ @@ -1932,6 +1935,10 @@ static const struct mount_opts { {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET}, {Opt_no_prefetch_block_bitmaps, EXT4_MOUNT_NO_PREFETCH_BLOCK_BITMAPS, MOPT_SET}, + {Opt_buffered_iomap, EXT4_MOUNT2_BUFFERED_IOMAP, + MOPT_SET | MOPT_2 | MOPT_EXT4_ONLY}, + {Opt_nobuffered_iomap, EXT4_MOUNT2_BUFFERED_IOMAP, + MOPT_CLEAR | MOPT_2 | MOPT_EXT4_ONLY}, #ifdef CONFIG_EXT4_DEBUG {Opt_fc_debug_force, EXT4_MOUNT2_JOURNAL_FAST_COMMIT, MOPT_SET | MOPT_2 | MOPT_EXT4_ONLY}, -- 2.52.0