From: Geliang Tang tanggeliang@kylinos.cn
In order to allow users to develop their own BPF-based path manager, this patch defines a struct ops "mptcp_pm_ops" for an MPTCP path manager, which contains a set of interfaces. Currently only init() and release() interfaces are included, subsequent patches will add others step by step.
Add a set of functions to register, unregister, find and validate a given path manager struct ops.
"list" is used to add this path manager to mptcp_pm_list list when it is registered. "name" is used to identify this path manager. mptcp_pm_find() uses "name" to find a path manager on the list.
mptcp_pm_unregister is not used in this set, but will be invoked in .unreg of struct bpf_struct_ops. mptcp_pm_validate() will be invoked in .validate of struct bpf_struct_ops. That's why they are exported.
Signed-off-by: Geliang Tang tanggeliang@kylinos.cn Reviewed-by: Matthieu Baerts (NGI0) matttbe@kernel.org Signed-off-by: Matthieu Baerts (NGI0) matttbe@kernel.org --- include/net/mptcp.h | 12 ++++++++++++ net/mptcp/pm.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++ net/mptcp/protocol.h | 5 +++++ 3 files changed, 67 insertions(+)
diff --git a/include/net/mptcp.h b/include/net/mptcp.h index 2c85ca92bb1c39989ae08a74ff4ef9b42099e60d..645d15695e3f5ec4b945bb543630f3dcc54453f2 100644 --- a/include/net/mptcp.h +++ b/include/net/mptcp.h @@ -14,6 +14,7 @@
struct mptcp_info; struct mptcp_sock; +struct mptcp_pm_addr_entry; struct seq_file;
/* MPTCP sk_buff extension data */ @@ -121,6 +122,17 @@ struct mptcp_sched_ops { void (*release)(struct mptcp_sock *msk); } ____cacheline_aligned_in_smp;
+#define MPTCP_PM_NAME_MAX 16 + +struct mptcp_pm_ops { + char name[MPTCP_PM_NAME_MAX]; + struct module *owner; + struct list_head list; + + void (*init)(struct mptcp_sock *msk); + void (*release)(struct mptcp_sock *msk); +} ____cacheline_aligned_in_smp; + #ifdef CONFIG_MPTCP void mptcp_init(void);
diff --git a/net/mptcp/pm.c b/net/mptcp/pm.c index 85ee999729a1c37f42bb21490d7f68d186e6734f..f4948a2cf9be078043bd237f56a57c27804ef4db 100644 --- a/net/mptcp/pm.c +++ b/net/mptcp/pm.c @@ -5,6 +5,8 @@ */ #define pr_fmt(fmt) "MPTCP: " fmt
+#include <linux/rculist.h> +#include <linux/spinlock.h> #include "protocol.h" #include "mib.h"
@@ -18,6 +20,9 @@ struct mptcp_pm_add_entry { struct mptcp_sock *sock; };
+static DEFINE_SPINLOCK(mptcp_pm_list_lock); +static LIST_HEAD(mptcp_pm_list); + /* path manager helpers */
/* if sk is ipv4 or ipv6_only allows only same-family local and remote addresses, @@ -1015,3 +1020,48 @@ void __init mptcp_pm_init(void) mptcp_pm_kernel_register(); mptcp_pm_nl_init(); } + +/* Must be called with rcu read lock held */ +struct mptcp_pm_ops *mptcp_pm_find(const char *name) +{ + struct mptcp_pm_ops *pm_ops; + + list_for_each_entry_rcu(pm_ops, &mptcp_pm_list, list) { + if (!strcmp(pm_ops->name, name)) + return pm_ops; + } + + return NULL; +} + +int mptcp_pm_validate(struct mptcp_pm_ops *pm_ops) +{ + return 0; +} + +int mptcp_pm_register(struct mptcp_pm_ops *pm_ops) +{ + int ret; + + ret = mptcp_pm_validate(pm_ops); + if (ret) + return ret; + + spin_lock(&mptcp_pm_list_lock); + if (mptcp_pm_find(pm_ops->name)) { + spin_unlock(&mptcp_pm_list_lock); + return -EEXIST; + } + list_add_tail_rcu(&pm_ops->list, &mptcp_pm_list); + spin_unlock(&mptcp_pm_list_lock); + + pr_debug("%s registered\n", pm_ops->name); + return 0; +} + +void mptcp_pm_unregister(struct mptcp_pm_ops *pm_ops) +{ + spin_lock(&mptcp_pm_list_lock); + list_del_rcu(&pm_ops->list); + spin_unlock(&mptcp_pm_list_lock); +} diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h index 15e2a03025ecb4cae44ccb700fcbbdd06ab806d1..ac8a178426e4ef495d7c5b5b9bd4c8b8835d71e4 100644 --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -1050,6 +1050,11 @@ int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_ void mptcp_pm_remove_addr_entry(struct mptcp_sock *msk, struct mptcp_pm_addr_entry *entry);
+struct mptcp_pm_ops *mptcp_pm_find(const char *name); +int mptcp_pm_register(struct mptcp_pm_ops *pm_ops); +void mptcp_pm_unregister(struct mptcp_pm_ops *pm_ops); +int mptcp_pm_validate(struct mptcp_pm_ops *pm_ops); + void mptcp_userspace_pm_free_local_addr_list(struct mptcp_sock *msk);
void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk,