blkcg: simplify blkg_conf_prep()
blkg_conf_prep() implements "MAJ:MIN VAL" parsing manually, which is
unnecessary. Just use sscanf("%u:%u %llu"). This might not reject
some malformed input (extra input at the end) but we don't care.
Signed-off-by: Tejun Heo <tj@kernel.org>
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 1e1ee2a..b07a501 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -987,57 +987,16 @@
{
struct gendisk *disk;
struct blkio_group *blkg;
- char *buf, *s[4], *p, *major_s, *minor_s;
- unsigned long major, minor;
- int i = 0, ret = -EINVAL;
- int part;
- dev_t dev;
- u64 temp;
+ unsigned int major, minor;
+ unsigned long long v;
+ int part, ret;
- buf = kstrdup(input, GFP_KERNEL);
- if (!buf)
- return -ENOMEM;
+ if (sscanf(input, "%u:%u %llu", &major, &minor, &v) != 3)
+ return -EINVAL;
- memset(s, 0, sizeof(s));
-
- while ((p = strsep(&buf, " ")) != NULL) {
- if (!*p)
- continue;
-
- s[i++] = p;
-
- /* Prevent from inputing too many things */
- if (i == 3)
- break;
- }
-
- if (i != 2)
- goto out;
-
- p = strsep(&s[0], ":");
- if (p != NULL)
- major_s = p;
- else
- goto out;
-
- minor_s = s[0];
- if (!minor_s)
- goto out;
-
- if (strict_strtoul(major_s, 10, &major))
- goto out;
-
- if (strict_strtoul(minor_s, 10, &minor))
- goto out;
-
- dev = MKDEV(major, minor);
-
- if (strict_strtoull(s[1], 10, &temp))
- goto out;
-
- disk = get_gendisk(dev, &part);
+ disk = get_gendisk(MKDEV(major, minor), &part);
if (!disk || part)
- goto out;
+ return -EINVAL;
rcu_read_lock();
@@ -1059,16 +1018,13 @@
msleep(10);
ret = restart_syscall();
}
- goto out;
+ return ret;
}
ctx->disk = disk;
ctx->blkg = blkg;
- ctx->v = temp;
- ret = 0;
-out:
- kfree(buf);
- return ret;
+ ctx->v = v;
+ return 0;
}
/**
