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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /net/core/netclassid_cgroup.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'net/core/netclassid_cgroup.c')
-rw-r--r--net/core/netclassid_cgroup.c146
1 files changed, 146 insertions, 0 deletions
diff --git a/net/core/netclassid_cgroup.c b/net/core/netclassid_cgroup.c
new file mode 100644
index 000000000..d6a70aeaa
--- /dev/null
+++ b/net/core/netclassid_cgroup.c
@@ -0,0 +1,146 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * net/core/netclassid_cgroup.c Classid Cgroupfs Handling
+ *
+ * Authors: Thomas Graf <tgraf@suug.ch>
+ */
+
+#include <linux/slab.h>
+#include <linux/cgroup.h>
+#include <linux/fdtable.h>
+#include <linux/sched/task.h>
+
+#include <net/cls_cgroup.h>
+#include <net/sock.h>
+
+static inline struct cgroup_cls_state *css_cls_state(struct cgroup_subsys_state *css)
+{
+ return css ? container_of(css, struct cgroup_cls_state, css) : NULL;
+}
+
+struct cgroup_cls_state *task_cls_state(struct task_struct *p)
+{
+ return css_cls_state(task_css_check(p, net_cls_cgrp_id,
+ rcu_read_lock_bh_held()));
+}
+EXPORT_SYMBOL_GPL(task_cls_state);
+
+static struct cgroup_subsys_state *
+cgrp_css_alloc(struct cgroup_subsys_state *parent_css)
+{
+ struct cgroup_cls_state *cs;
+
+ cs = kzalloc(sizeof(*cs), GFP_KERNEL);
+ if (!cs)
+ return ERR_PTR(-ENOMEM);
+
+ return &cs->css;
+}
+
+static int cgrp_css_online(struct cgroup_subsys_state *css)
+{
+ struct cgroup_cls_state *cs = css_cls_state(css);
+ struct cgroup_cls_state *parent = css_cls_state(css->parent);
+
+ if (parent)
+ cs->classid = parent->classid;
+
+ return 0;
+}
+
+static void cgrp_css_free(struct cgroup_subsys_state *css)
+{
+ kfree(css_cls_state(css));
+}
+
+/*
+ * To avoid freezing of sockets creation for tasks with big number of threads
+ * and opened sockets lets release file_lock every 1000 iterated descriptors.
+ * New sockets will already have been created with new classid.
+ */
+
+struct update_classid_context {
+ u32 classid;
+ unsigned int batch;
+};
+
+#define UPDATE_CLASSID_BATCH 1000
+
+static int update_classid_sock(const void *v, struct file *file, unsigned int n)
+{
+ struct update_classid_context *ctx = (void *)v;
+ struct socket *sock = sock_from_file(file);
+
+ if (sock)
+ sock_cgroup_set_classid(&sock->sk->sk_cgrp_data, ctx->classid);
+ if (--ctx->batch == 0) {
+ ctx->batch = UPDATE_CLASSID_BATCH;
+ return n + 1;
+ }
+ return 0;
+}
+
+static void update_classid_task(struct task_struct *p, u32 classid)
+{
+ struct update_classid_context ctx = {
+ .classid = classid,
+ .batch = UPDATE_CLASSID_BATCH
+ };
+ unsigned int fd = 0;
+
+ do {
+ task_lock(p);
+ fd = iterate_fd(p->files, fd, update_classid_sock, &ctx);
+ task_unlock(p);
+ cond_resched();
+ } while (fd);
+}
+
+static void cgrp_attach(struct cgroup_taskset *tset)
+{
+ struct cgroup_subsys_state *css;
+ struct task_struct *p;
+
+ cgroup_taskset_for_each(p, css, tset) {
+ update_classid_task(p, css_cls_state(css)->classid);
+ }
+}
+
+static u64 read_classid(struct cgroup_subsys_state *css, struct cftype *cft)
+{
+ return css_cls_state(css)->classid;
+}
+
+static int write_classid(struct cgroup_subsys_state *css, struct cftype *cft,
+ u64 value)
+{
+ struct cgroup_cls_state *cs = css_cls_state(css);
+ struct css_task_iter it;
+ struct task_struct *p;
+
+ cs->classid = (u32)value;
+
+ css_task_iter_start(css, 0, &it);
+ while ((p = css_task_iter_next(&it)))
+ update_classid_task(p, cs->classid);
+ css_task_iter_end(&it);
+
+ return 0;
+}
+
+static struct cftype ss_files[] = {
+ {
+ .name = "classid",
+ .read_u64 = read_classid,
+ .write_u64 = write_classid,
+ },
+ { } /* terminate */
+};
+
+struct cgroup_subsys net_cls_cgrp_subsys = {
+ .css_alloc = cgrp_css_alloc,
+ .css_online = cgrp_css_online,
+ .css_free = cgrp_css_free,
+ .attach = cgrp_attach,
+ .legacy_cftypes = ss_files,
+};