cgroup: replace cftype->write_string() with cftype->write()
Convert all cftype->write_string() users to the new cftype->write()
which maps directly to kernfs write operation and has full access to
kernfs and cgroup contexts. The conversions are mostly mechanical.
* @css and @cft are accessed using of_css() and of_cft() accessors
respectively instead of being specified as arguments.
* Should return @nbytes on success instead of 0.
* @buf is not trimmed automatically. Trim if necessary. Note that
blkcg and netprio don't need this as the parsers already handle
whitespaces.
cftype->write_string() has no user left after the conversions and
removed.
While at it, remove unnecessary local variable @p in
cgroup_subtree_control_write() and stale comment about
CGROUP_LOCAL_BUFFER_SIZE in cgroup_freezer.c.
This patch doesn't introduce any visible behavior changes.
v2: netprio was missing from conversion. Converted.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Aristeu Rozanski <arozansk@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: "David S. Miller" <davem@davemloft.net>
diff --git a/security/device_cgroup.c b/security/device_cgroup.c
index 9134dbf..7dbac40 100644
--- a/security/device_cgroup.c
+++ b/security/device_cgroup.c
@@ -767,27 +767,27 @@
return rc;
}
-static int devcgroup_access_write(struct cgroup_subsys_state *css,
- struct cftype *cft, char *buffer)
+static ssize_t devcgroup_access_write(struct kernfs_open_file *of,
+ char *buf, size_t nbytes, loff_t off)
{
int retval;
mutex_lock(&devcgroup_mutex);
- retval = devcgroup_update_access(css_to_devcgroup(css),
- cft->private, buffer);
+ retval = devcgroup_update_access(css_to_devcgroup(of_css(of)),
+ of_cft(of)->private, strstrip(buf));
mutex_unlock(&devcgroup_mutex);
- return retval;
+ return retval ?: nbytes;
}
static struct cftype dev_cgroup_files[] = {
{
.name = "allow",
- .write_string = devcgroup_access_write,
+ .write = devcgroup_access_write,
.private = DEVCG_ALLOW,
},
{
.name = "deny",
- .write_string = devcgroup_access_write,
+ .write = devcgroup_access_write,
.private = DEVCG_DENY,
},
{