From 726fa6945e6e5f0389bf47a790e1df734a67de54 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Sun, 1 Apr 2012 14:38:43 -0700 Subject: [PATCH] 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 --- block/blk-cgroup.c | 64 ++++++++-------------------------------------- 1 file changed, 10 insertions(+), 54 deletions(-) diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 1e1ee2af7b5f..b07a501839e7 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -987,57 +987,16 @@ static int blkg_conf_prep(struct blkio_cgroup *blkcg, const char *input, { 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; - - 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; + if (sscanf(input, "%u:%u %llu", &major, &minor, &v) != 3) + return -EINVAL; - 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 @@ static int blkg_conf_prep(struct blkio_cgroup *blkcg, const char *input, 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; } /** -- 2.30.2