net: netprio_cgroup: rework update socket logic

[mirror_ubuntu-artful-kernel.git] / net / core / netprio_cgroup.c

diff --git a/net/core/netprio_cgroup.c b/net/core/netprio_cgroup.c
index b2e9caa1ad1aa761ba98886a23ce3823bdc179ee..63d15e8f80e91c1f86461df2918d63cffeab5e8a 100644 (file)
--- a/net/core/netprio_cgroup.c
+++ b/net/core/netprio_cgroup.c
@@ -25,6 +25,8 @@
 #include <net/sock.h>
 #include <net/netprio_cgroup.h>
 
+#include <linux/fdtable.h>
+
 #define PRIOIDX_SZ 128
 
 static unsigned long prioidx_map[PRIOIDX_SZ];
@@ -272,6 +274,56 @@ out_free_devname:
        return ret;
 }
 
+void net_prio_attach(struct cgroup *cgrp, struct cgroup_taskset *tset)
+{
+       struct task_struct *p;
+       char *tmp = kzalloc(sizeof(char) * PATH_MAX, GFP_KERNEL);
+
+       if (!tmp) {
+               pr_warn("Unable to attach cgrp due to alloc failure!\n");
+               return;
+       }
+
+       cgroup_taskset_for_each(p, cgrp, tset) {
+               unsigned int fd;
+               struct fdtable *fdt;
+               struct files_struct *files;
+
+               task_lock(p);
+               files = p->files;
+               if (!files) {
+                       task_unlock(p);
+                       continue;
+               }
+
+               rcu_read_lock();
+               fdt = files_fdtable(files);
+               for (fd = 0; fd < fdt->max_fds; fd++) {
+                       char *path;
+                       struct file *file;
+                       struct socket *sock;
+                       unsigned long s;
+                       int rv, err = 0;
+
+                       file = fcheck_files(files, fd);
+                       if (!file)
+                               continue;
+
+                       path = d_path(&file->f_path, tmp, PAGE_SIZE);
+                       rv = sscanf(path, "socket:[%lu]", &s);
+                       if (rv <= 0)
+                               continue;
+
+                       sock = sock_from_file(file, &err);
+                       if (!err)
+                               sock_update_netprioidx(sock->sk, p);
+               }
+               rcu_read_unlock();
+               task_unlock(p);
+       }
+       kfree(tmp);
+}
+
 static struct cftype ss_files[] = {
        {
                .name = "prioidx",
@@ -289,6 +341,7 @@ struct cgroup_subsys net_prio_subsys = {
        .name           = "net_prio",
        .create         = cgrp_create,
        .destroy        = cgrp_destroy,
+       .attach         = net_prio_attach,
 #ifdef CONFIG_NETPRIO_CGROUP
        .subsys_id      = net_prio_subsys_id,
 #endif