ext4: Add mount option to set kjournald's I/O priority
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Jens Axboe <jens.axboe@oracle.com>
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 8036392..8ff8709 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1013,7 +1013,7 @@
Opt_ignore, Opt_barrier, Opt_err, Opt_resize, Opt_usrquota,
Opt_grpquota, Opt_extents, Opt_noextents, Opt_i_version,
Opt_stripe, Opt_delalloc, Opt_nodelalloc,
- Opt_inode_readahead_blks
+ Opt_inode_readahead_blks, Opt_journal_ioprio
};
static const match_table_t tokens = {
@@ -1074,6 +1074,7 @@
{Opt_delalloc, "delalloc"},
{Opt_nodelalloc, "nodelalloc"},
{Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
+ {Opt_journal_ioprio, "journal_ioprio=%u"},
{Opt_err, NULL},
};
@@ -1098,8 +1099,11 @@
return sb_block;
}
+#define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
+
static int parse_options(char *options, struct super_block *sb,
unsigned long *journal_devnum,
+ unsigned int *journal_ioprio,
ext4_fsblk_t *n_blocks_count, int is_remount)
{
struct ext4_sb_info *sbi = EXT4_SB(sb);
@@ -1492,6 +1496,14 @@
return 0;
sbi->s_inode_readahead_blks = option;
break;
+ case Opt_journal_ioprio:
+ if (match_int(&args[0], &option))
+ return 0;
+ if (option < 0 || option > 7)
+ break;
+ *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE,
+ option);
+ break;
default:
printk(KERN_ERR
"EXT4-fs: Unrecognized mount option \"%s\" "
@@ -2035,6 +2047,7 @@
int features;
__u64 blocks_count;
int err;
+ unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
if (!sbi)
@@ -2141,7 +2154,8 @@
set_opt(sbi->s_mount_opt, DELALLOC);
- if (!parse_options((char *) data, sb, &journal_devnum, NULL, 0))
+ if (!parse_options((char *) data, sb, &journal_devnum,
+ &journal_ioprio, NULL, 0))
goto failed_mount;
sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
@@ -2506,6 +2520,7 @@
default:
break;
}
+ set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
no_journal:
@@ -3127,6 +3142,7 @@
unsigned long old_sb_flags;
struct ext4_mount_options old_opts;
ext4_group_t g;
+ unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
int err;
#ifdef CONFIG_QUOTA
int i;
@@ -3145,11 +3161,14 @@
for (i = 0; i < MAXQUOTAS; i++)
old_opts.s_qf_names[i] = sbi->s_qf_names[i];
#endif
+ if (sbi->s_journal && sbi->s_journal->j_task->io_context)
+ journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
/*
* Allow the "check" option to be passed as a remount option.
*/
- if (!parse_options(data, sb, NULL, &n_blocks_count, 1)) {
+ if (!parse_options(data, sb, NULL, &journal_ioprio,
+ &n_blocks_count, 1)) {
err = -EINVAL;
goto restore_opts;
}
@@ -3162,8 +3181,10 @@
es = sbi->s_es;
- if (sbi->s_journal)
+ if (sbi->s_journal) {
ext4_init_journal_params(sb, sbi->s_journal);
+ set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
+ }
if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY) ||
n_blocks_count > ext4_blocks_count(es)) {