diff options
Diffstat (limited to '')
| -rw-r--r-- | fs/btrfs/sysfs.c | 31 |
1 files changed, 30 insertions, 1 deletions
diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c index e155b7ce1ee5..5211d13d73f8 100644 --- a/fs/btrfs/sysfs.c +++ b/fs/btrfs/sysfs.c @@ -1309,6 +1309,7 @@ static const char *btrfs_read_policy_name[] = { "pid", #ifdef CONFIG_BTRFS_EXPERIMENTAL "round-robin", + "devid", #endif }; @@ -1364,8 +1365,11 @@ static ssize_t btrfs_read_policy_show(struct kobject *kobj, if (i == BTRFS_READ_POLICY_RR) ret += sysfs_emit_at(buf, ret, ":%u", READ_ONCE(fs_devices->rr_min_contig_read)); -#endif + if (i == BTRFS_READ_POLICY_DEVID) + ret += sysfs_emit_at(buf, ret, ":%llu", + READ_ONCE(fs_devices->read_devid)); +#endif if (i == policy) ret += sysfs_emit_at(buf, ret, "]"); } @@ -1421,6 +1425,31 @@ static ssize_t btrfs_read_policy_store(struct kobject *kobj, return len; } + + if (index == BTRFS_READ_POLICY_DEVID) { + if (value != -1) { + BTRFS_DEV_LOOKUP_ARGS(args); + + /* Validate input devid. */ + args.devid = value; + if (btrfs_find_device(fs_devices, &args) == NULL) + return -EINVAL; + } else { + /* Set default devid to the devid of the latest device. */ + value = fs_devices->latest_dev->devid; + } + + if (index != READ_ONCE(fs_devices->read_policy) || + value != READ_ONCE(fs_devices->read_devid)) { + WRITE_ONCE(fs_devices->read_policy, index); + WRITE_ONCE(fs_devices->read_devid, value); + + btrfs_info(fs_devices->fs_info, "read policy set to '%s:%llu'", + btrfs_read_policy_name[index], value); + } + + return len; + } #endif if (index != READ_ONCE(fs_devices->read_policy)) { WRITE_ONCE(fs_devices->read_policy, index); |