From: Tejun Heo <tj@kernel.org>
Date: Tue, 12 Mar 2013 18:30:04 +0000 (-0700)
Subject: cpumask: implement cpumask_parse()
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=ba630e4940924ad1962883c207a62890778ced63;p=linux-beck.git

cpumask: implement cpumask_parse()

We have cpulist_parse() but not cpumask_parse().  Implement it using
bitmap_parse().

bitmap_parse() is weird in that it takes @len for a string in
kernel-memory which also is inconsistent with bitmap_parselist().
Make cpumask_parse() calculate the length and don't expose the
inconsistency to cpumask users.  Maybe we can fix up bitmap_parse()
later.

This will be used to expose workqueue cpumask knobs to userland via
sysfs.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
---

diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h
index 032560295fcb..d08e4d2a9b92 100644
--- a/include/linux/cpumask.h
+++ b/include/linux/cpumask.h
@@ -590,6 +590,21 @@ static inline int cpulist_scnprintf(char *buf, int len,
 				    nr_cpumask_bits);
 }
 
+/**
+ * cpumask_parse - extract a cpumask from from a string
+ * @buf: the buffer to extract from
+ * @dstp: the cpumask to set.
+ *
+ * Returns -errno, or 0 for success.
+ */
+static inline int cpumask_parse(const char *buf, struct cpumask *dstp)
+{
+	char *nl = strchr(buf, '\n');
+	int len = nl ? nl - buf : strlen(buf);
+
+	return bitmap_parse(buf, len, cpumask_bits(dstp), nr_cpumask_bits);
+}
+
 /**
  * cpulist_parse - extract a cpumask from a user string of ranges
  * @buf: the buffer to extract from