]> git.proxmox.com Git - mirror_ubuntu-focal-kernel.git/blobdiff - net/sched/cls_api.c
Merge tag 'dmaengine-fix-4.11-rc5' of git://git.infradead.org/users/vkoul/slave-dma
[mirror_ubuntu-focal-kernel.git] / net / sched / cls_api.c
index 1ecdf809b5fa8913d56bb4194ac193274d4d625a..732f7cae459d4656aa8d69020f44a66abb501f34 100644 (file)
@@ -19,6 +19,7 @@
 #include <linux/kernel.h>
 #include <linux/string.h>
 #include <linux/errno.h>
+#include <linux/err.h>
 #include <linux/skbuff.h>
 #include <linux/init.h>
 #include <linux/kmod.h>
@@ -38,14 +39,14 @@ static DEFINE_RWLOCK(cls_mod_lock);
 
 /* Find classifier type by string name */
 
-static const struct tcf_proto_ops *tcf_proto_lookup_ops(struct nlattr *kind)
+static const struct tcf_proto_ops *tcf_proto_lookup_ops(const char *kind)
 {
        const struct tcf_proto_ops *t, *res = NULL;
 
        if (kind) {
                read_lock(&cls_mod_lock);
                list_for_each_entry(t, &tcf_proto_base, head) {
-                       if (nla_strcmp(kind, t->kind) == 0) {
+                       if (strcmp(kind, t->kind) == 0) {
                                if (try_module_get(t->owner))
                                        res = t;
                                break;
@@ -127,6 +128,77 @@ static inline u32 tcf_auto_prio(struct tcf_proto *tp)
        return first;
 }
 
+static struct tcf_proto *tcf_proto_create(const char *kind, u32 protocol,
+                                         u32 prio, u32 parent, struct Qdisc *q)
+{
+       struct tcf_proto *tp;
+       int err;
+
+       tp = kzalloc(sizeof(*tp), GFP_KERNEL);
+       if (!tp)
+               return ERR_PTR(-ENOBUFS);
+
+       err = -ENOENT;
+       tp->ops = tcf_proto_lookup_ops(kind);
+       if (!tp->ops) {
+#ifdef CONFIG_MODULES
+               rtnl_unlock();
+               request_module("cls_%s", kind);
+               rtnl_lock();
+               tp->ops = tcf_proto_lookup_ops(kind);
+               /* We dropped the RTNL semaphore in order to perform
+                * the module load. So, even if we succeeded in loading
+                * the module we have to replay the request. We indicate
+                * this using -EAGAIN.
+                */
+               if (tp->ops) {
+                       module_put(tp->ops->owner);
+                       err = -EAGAIN;
+               } else {
+                       err = -ENOENT;
+               }
+               goto errout;
+#endif
+       }
+       tp->classify = tp->ops->classify;
+       tp->protocol = protocol;
+       tp->prio = prio;
+       tp->classid = parent;
+       tp->q = q;
+
+       err = tp->ops->init(tp);
+       if (err) {
+               module_put(tp->ops->owner);
+               goto errout;
+       }
+       return tp;
+
+errout:
+       kfree(tp);
+       return ERR_PTR(err);
+}
+
+static bool tcf_proto_destroy(struct tcf_proto *tp, bool force)
+{
+       if (tp->ops->destroy(tp, force)) {
+               module_put(tp->ops->owner);
+               kfree_rcu(tp, rcu);
+               return true;
+       }
+       return false;
+}
+
+void tcf_destroy_chain(struct tcf_proto __rcu **fl)
+{
+       struct tcf_proto *tp;
+
+       while ((tp = rtnl_dereference(*fl)) != NULL) {
+               RCU_INIT_POINTER(*fl, tp->next);
+               tcf_proto_destroy(tp, true);
+       }
+}
+EXPORT_SYMBOL(tcf_destroy_chain);
+
 /* Add/change/delete/get a filter node */
 
 static int tc_ctl_tfilter(struct sk_buff *skb, struct nlmsghdr *n)
@@ -142,8 +214,8 @@ static int tc_ctl_tfilter(struct sk_buff *skb, struct nlmsghdr *n)
        struct Qdisc  *q;
        struct tcf_proto __rcu **back;
        struct tcf_proto __rcu **chain;
+       struct tcf_proto *next;
        struct tcf_proto *tp;
-       const struct tcf_proto_ops *tp_ops;
        const struct Qdisc_class_ops *cops;
        unsigned long cl;
        unsigned long fh;
@@ -222,9 +294,10 @@ replay:
 
        /* And the last stroke */
        chain = cops->tcf_chain(q, cl);
-       err = -EINVAL;
-       if (chain == NULL)
+       if (chain == NULL) {
+               err = -EINVAL;
                goto errout;
+       }
        if (n->nlmsg_type == RTM_DELTFILTER && prio == 0) {
                tfilter_notify_chain(net, skb, n, chain, RTM_DELTFILTER);
                tcf_destroy_chain(chain);
@@ -239,10 +312,13 @@ replay:
                if (tp->prio >= prio) {
                        if (tp->prio == prio) {
                                if (!nprio ||
-                                   (tp->protocol != protocol && protocol))
+                                   (tp->protocol != protocol && protocol)) {
+                                       err = -EINVAL;
                                        goto errout;
-                       } else
+                               }
+                       } else {
                                tp = NULL;
+                       }
                        break;
                }
        }
@@ -250,109 +326,69 @@ replay:
        if (tp == NULL) {
                /* Proto-tcf does not exist, create new one */
 
-               if (tca[TCA_KIND] == NULL || !protocol)
+               if (tca[TCA_KIND] == NULL || !protocol) {
+                       err = -EINVAL;
                        goto errout;
+               }
 
-               err = -ENOENT;
                if (n->nlmsg_type != RTM_NEWTFILTER ||
-                   !(n->nlmsg_flags & NLM_F_CREATE))
+                   !(n->nlmsg_flags & NLM_F_CREATE)) {
+                       err = -ENOENT;
                        goto errout;
+               }
 
+               if (!nprio)
+                       nprio = TC_H_MAJ(tcf_auto_prio(rtnl_dereference(*back)));
 
-               /* Create new proto tcf */
-
-               err = -ENOBUFS;
-               tp = kzalloc(sizeof(*tp), GFP_KERNEL);
-               if (tp == NULL)
-                       goto errout;
-               err = -ENOENT;
-               tp_ops = tcf_proto_lookup_ops(tca[TCA_KIND]);
-               if (tp_ops == NULL) {
-#ifdef CONFIG_MODULES
-                       struct nlattr *kind = tca[TCA_KIND];
-                       char name[IFNAMSIZ];
-
-                       if (kind != NULL &&
-                           nla_strlcpy(name, kind, IFNAMSIZ) < IFNAMSIZ) {
-                               rtnl_unlock();
-                               request_module("cls_%s", name);
-                               rtnl_lock();
-                               tp_ops = tcf_proto_lookup_ops(kind);
-                               /* We dropped the RTNL semaphore in order to
-                                * perform the module load.  So, even if we
-                                * succeeded in loading the module we have to
-                                * replay the request.  We indicate this using
-                                * -EAGAIN.
-                                */
-                               if (tp_ops != NULL) {
-                                       module_put(tp_ops->owner);
-                                       err = -EAGAIN;
-                               }
-                       }
-#endif
-                       kfree(tp);
-                       goto errout;
-               }
-               tp->ops = tp_ops;
-               tp->protocol = protocol;
-               tp->prio = nprio ? :
-                              TC_H_MAJ(tcf_auto_prio(rtnl_dereference(*back)));
-               tp->q = q;
-               tp->classify = tp_ops->classify;
-               tp->classid = parent;
-
-               err = tp_ops->init(tp);
-               if (err != 0) {
-                       module_put(tp_ops->owner);
-                       kfree(tp);
+               tp = tcf_proto_create(nla_data(tca[TCA_KIND]),
+                                     protocol, nprio, parent, q);
+               if (IS_ERR(tp)) {
+                       err = PTR_ERR(tp);
                        goto errout;
                }
-
                tp_created = 1;
-
-       } else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind))
+       } else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
+               err = -EINVAL;
                goto errout;
+       }
 
        fh = tp->ops->get(tp, t->tcm_handle);
 
        if (fh == 0) {
                if (n->nlmsg_type == RTM_DELTFILTER && t->tcm_handle == 0) {
-                       struct tcf_proto *next = rtnl_dereference(tp->next);
-
+                       next = rtnl_dereference(tp->next);
                        RCU_INIT_POINTER(*back, next);
-
                        tfilter_notify(net, skb, n, tp, fh,
                                       RTM_DELTFILTER, false);
-                       tcf_destroy(tp, true);
+                       tcf_proto_destroy(tp, true);
                        err = 0;
                        goto errout;
                }
 
-               err = -ENOENT;
                if (n->nlmsg_type != RTM_NEWTFILTER ||
-                   !(n->nlmsg_flags & NLM_F_CREATE))
+                   !(n->nlmsg_flags & NLM_F_CREATE)) {
+                       err = -ENOENT;
                        goto errout;
+               }
        } else {
                switch (n->nlmsg_type) {
                case RTM_NEWTFILTER:
-                       err = -EEXIST;
                        if (n->nlmsg_flags & NLM_F_EXCL) {
                                if (tp_created)
-                                       tcf_destroy(tp, true);
+                                       tcf_proto_destroy(tp, true);
+                               err = -EEXIST;
                                goto errout;
                        }
                        break;
                case RTM_DELTFILTER:
                        err = tp->ops->delete(tp, fh);
-                       if (err == 0) {
-                               struct tcf_proto *next = rtnl_dereference(tp->next);
-
-                               tfilter_notify(net, skb, n, tp,
-                                              t->tcm_handle,
-                                              RTM_DELTFILTER, false);
-                               if (tcf_destroy(tp, false))
-                                       RCU_INIT_POINTER(*back, next);
-                       }
+                       if (err)
+                               goto errout;
+                       next = rtnl_dereference(tp->next);
+                       tfilter_notify(net, skb, n, tp, t->tcm_handle,
+                                      RTM_DELTFILTER, false);
+                       if (tcf_proto_destroy(tp, false))
+                               RCU_INIT_POINTER(*back, next);
                        goto errout;
                case RTM_GETTFILTER:
                        err = tfilter_notify(net, skb, n, tp, fh,
@@ -374,7 +410,7 @@ replay:
                tfilter_notify(net, skb, n, tp, fh, RTM_NEWTFILTER, false);
        } else {
                if (tp_created)
-                       tcf_destroy(tp, true);
+                       tcf_proto_destroy(tp, true);
        }
 
 errout: