iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

ext4: make mb_optimize_scan option work with set/unset mount cmd

Browse Source 
After moving to the new mount API, mb_optimize_scan mount option
handling was not working as expected due to the parsed value always
being overwritten by default. Refactor and fix this to the expected
behavior described below:

*  mb_optimize_scan=1 - On
*  mb_optimize_scan=0 - Off
*  mb_optimize_scan not passed - On if no. of BGs > threshold else off
*  Remounts retain previous value unless we explicitly pass the option
   with a new value

Fixes: cebe85d570 ("ext4: switch to the new mount api")
Cc: stable@kernel.org
Reported-by: Ritesh Harjani <riteshh@linux.ibm.com>
Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/c98970fe99f26718586d02e942f293300fb48ef3.1646732698.git.ojaswin@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This commit is contained in:
Ojaswin Mujoo 2022-03-08 15:22:00 +05:30 committed by Theodore Ts'o
parent cc5095747e
commit 27b38686a3
1 changed files with 14 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
fs/ext4/super.c
View File

@ -2021,12 +2021,12 @@ static int ext4_set_test_dummy_encryption(struct super_block *sb, char *arg)
#define EXT4_SPEC_s_commit_interval (1 << 16)
#define EXT4_SPEC_s_fc_debug_max_replay (1 << 17)
#define EXT4_SPEC_s_sb_block (1 << 18)
#define EXT4_SPEC_mb_optimize_scan (1 << 19)
struct ext4_fs_context {
char *s_qf_names[EXT4_MAXQUOTAS];
char *test_dummy_enc_arg;
int s_jquota_fmt; /* Format of quota to use */
int mb_optimize_scan;
#ifdef CONFIG_EXT4_DEBUG
int s_fc_debug_max_replay;
#endif
@ -2464,12 +2464,17 @@ static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param)
ctx_clear_mount_opt(ctx, m->mount_opt);
return 0;
case Opt_mb_optimize_scan:
if (result.int_32 != 0 && result.int_32 != 1) {
if (result.int_32 == 1) {
ctx_set_mount_opt2(ctx, EXT4_MOUNT2_MB_OPTIMIZE_SCAN);
ctx->spec |= EXT4_SPEC_mb_optimize_scan;
} else if (result.int_32 == 0) {
ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_MB_OPTIMIZE_SCAN);
ctx->spec |= EXT4_SPEC_mb_optimize_scan;
} else {
ext4_msg(NULL, KERN_WARNING,
"mb_optimize_scan should be set to 0 or 1.");
return -EINVAL;
}
ctx->mb_optimize_scan = result.int_32;
return 0;
}
@ -4398,7 +4403,6 @@ static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)
/* Set defaults for the variables that will be set during parsing */
ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
ctx->mb_optimize_scan = DEFAULT_MB_OPTIMIZE_SCAN;
sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
sbi->s_sectors_written_start =
@ -5349,12 +5353,12 @@ no_journal:
* turned off by passing "mb_optimize_scan=0". This can also be
* turned on forcefully by passing "mb_optimize_scan=1".
*/
if (ctx->mb_optimize_scan == 1)
set_opt2(sb, MB_OPTIMIZE_SCAN);
else if (ctx->mb_optimize_scan == 0)
clear_opt2(sb, MB_OPTIMIZE_SCAN);
else if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD)
set_opt2(sb, MB_OPTIMIZE_SCAN);
if (!(ctx->spec & EXT4_SPEC_mb_optimize_scan)) {
if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD)
set_opt2(sb, MB_OPTIMIZE_SCAN);
else
clear_opt2(sb, MB_OPTIMIZE_SCAN);
}
err = ext4_mb_init(sb);
if (err) {