From 8bad74f9840f87661f20ced3dc80c84ab4fd55a1 Mon Sep 17 00:00:00 2001 From: Roman Gushchin Date: Fri, 28 Sep 2018 14:45:36 +0000 Subject: [PATCH] bpf: extend cgroup bpf core to allow multiple cgroup storage types In order to introduce per-cpu cgroup storage, let's generalize bpf cgroup core to support multiple cgroup storage types. Potentially, per-node cgroup storage can be added later. This commit is mostly a formal change that replaces cgroup_storage pointer with a array of cgroup_storage pointers. It doesn't actually introduce a new storage type, it will be done later. Each bpf program is now able to have one cgroup storage of each type. Signed-off-by: Roman Gushchin Acked-by: Song Liu Cc: Daniel Borkmann Cc: Alexei Starovoitov Signed-off-by: Daniel Borkmann --- include/linux/bpf-cgroup.h | 38 ++++++++++++++------ include/linux/bpf.h | 11 ++++-- kernel/bpf/cgroup.c | 74 ++++++++++++++++++++++++++------------ kernel/bpf/helpers.c | 15 ++++---- kernel/bpf/local_storage.c | 18 ++++++---- kernel/bpf/syscall.c | 9 +++-- kernel/bpf/verifier.c | 8 +++-- net/bpf/test_run.c | 20 +++++++---- 8 files changed, 136 insertions(+), 57 deletions(-) diff --git a/include/linux/bpf-cgroup.h b/include/linux/bpf-cgroup.h index f91b0f8ff3a9..e9871b012dac 100644 --- a/include/linux/bpf-cgroup.h +++ b/include/linux/bpf-cgroup.h @@ -2,6 +2,7 @@ #ifndef _BPF_CGROUP_H #define _BPF_CGROUP_H +#include #include #include #include @@ -22,7 +23,10 @@ struct bpf_cgroup_storage; extern struct static_key_false cgroup_bpf_enabled_key; #define cgroup_bpf_enabled static_branch_unlikely(&cgroup_bpf_enabled_key) -DECLARE_PER_CPU(void*, bpf_cgroup_storage); +DECLARE_PER_CPU(void*, bpf_cgroup_storage[MAX_BPF_CGROUP_STORAGE_TYPE]); + +#define for_each_cgroup_storage_type(stype) \ + for (stype = 0; stype < MAX_BPF_CGROUP_STORAGE_TYPE; stype++) struct bpf_cgroup_storage_map; @@ -43,7 +47,7 @@ struct bpf_cgroup_storage { struct bpf_prog_list { struct list_head node; struct bpf_prog *prog; - struct bpf_cgroup_storage *storage; + struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE]; }; struct bpf_prog_array; @@ -101,18 +105,29 @@ int __cgroup_bpf_run_filter_sock_ops(struct sock *sk, int __cgroup_bpf_check_dev_permission(short dev_type, u32 major, u32 minor, short access, enum bpf_attach_type type); -static inline void bpf_cgroup_storage_set(struct bpf_cgroup_storage *storage) +static inline enum bpf_cgroup_storage_type cgroup_storage_type( + struct bpf_map *map) { + return BPF_CGROUP_STORAGE_SHARED; +} + +static inline void bpf_cgroup_storage_set(struct bpf_cgroup_storage + *storage[MAX_BPF_CGROUP_STORAGE_TYPE]) +{ + enum bpf_cgroup_storage_type stype; struct bpf_storage_buffer *buf; - if (!storage) - return; + for_each_cgroup_storage_type(stype) { + if (!storage[stype]) + continue; - buf = READ_ONCE(storage->buf); - this_cpu_write(bpf_cgroup_storage, &buf->data[0]); + buf = READ_ONCE(storage[stype]->buf); + this_cpu_write(bpf_cgroup_storage[stype], &buf->data[0]); + } } -struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog); +struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog, + enum bpf_cgroup_storage_type stype); void bpf_cgroup_storage_free(struct bpf_cgroup_storage *storage); void bpf_cgroup_storage_link(struct bpf_cgroup_storage *storage, struct cgroup *cgroup, @@ -265,13 +280,14 @@ static inline int cgroup_bpf_prog_query(const union bpf_attr *attr, return -EINVAL; } -static inline void bpf_cgroup_storage_set(struct bpf_cgroup_storage *storage) {} +static inline void bpf_cgroup_storage_set( + struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE]) {} static inline int bpf_cgroup_storage_assign(struct bpf_prog *prog, struct bpf_map *map) { return 0; } static inline void bpf_cgroup_storage_release(struct bpf_prog *prog, struct bpf_map *map) {} static inline struct bpf_cgroup_storage *bpf_cgroup_storage_alloc( - struct bpf_prog *prog) { return 0; } + struct bpf_prog *prog, enum bpf_cgroup_storage_type stype) { return 0; } static inline void bpf_cgroup_storage_free( struct bpf_cgroup_storage *storage) {} @@ -293,6 +309,8 @@ static inline void bpf_cgroup_storage_free( #define BPF_CGROUP_RUN_PROG_SOCK_OPS(sock_ops) ({ 0; }) #define BPF_CGROUP_RUN_PROG_DEVICE_CGROUP(type,major,minor,access) ({ 0; }) +#define for_each_cgroup_storage_type(stype) for (; false; ) + #endif /* CONFIG_CGROUP_BPF */ #endif /* _BPF_CGROUP_H */ diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 988a00797bcd..b457fbe7b70b 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -272,6 +272,13 @@ struct bpf_prog_offload { u32 jited_len; }; +enum bpf_cgroup_storage_type { + BPF_CGROUP_STORAGE_SHARED, + __BPF_CGROUP_STORAGE_MAX +}; + +#define MAX_BPF_CGROUP_STORAGE_TYPE __BPF_CGROUP_STORAGE_MAX + struct bpf_prog_aux { atomic_t refcnt; u32 used_map_cnt; @@ -289,7 +296,7 @@ struct bpf_prog_aux { struct bpf_prog *prog; struct user_struct *user; u64 load_time; /* ns since boottime */ - struct bpf_map *cgroup_storage; + struct bpf_map *cgroup_storage[MAX_BPF_CGROUP_STORAGE_TYPE]; char name[BPF_OBJ_NAME_LEN]; #ifdef CONFIG_SECURITY void *security; @@ -358,7 +365,7 @@ int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr, */ struct bpf_prog_array_item { struct bpf_prog *prog; - struct bpf_cgroup_storage *cgroup_storage; + struct bpf_cgroup_storage *cgroup_storage[MAX_BPF_CGROUP_STORAGE_TYPE]; }; struct bpf_prog_array { diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c index 549f6fbcc461..00f6ed2e4f9a 100644 --- a/kernel/bpf/cgroup.c +++ b/kernel/bpf/cgroup.c @@ -25,6 +25,7 @@ EXPORT_SYMBOL(cgroup_bpf_enabled_key); */ void cgroup_bpf_put(struct cgroup *cgrp) { + enum bpf_cgroup_storage_type stype; unsigned int type; for (type = 0; type < ARRAY_SIZE(cgrp->bpf.progs); type++) { @@ -34,8 +35,10 @@ void cgroup_bpf_put(struct cgroup *cgrp) list_for_each_entry_safe(pl, tmp, progs, node) { list_del(&pl->node); bpf_prog_put(pl->prog); - bpf_cgroup_storage_unlink(pl->storage); - bpf_cgroup_storage_free(pl->storage); + for_each_cgroup_storage_type(stype) { + bpf_cgroup_storage_unlink(pl->storage[stype]); + bpf_cgroup_storage_free(pl->storage[stype]); + } kfree(pl); static_branch_dec(&cgroup_bpf_enabled_key); } @@ -97,6 +100,7 @@ static int compute_effective_progs(struct cgroup *cgrp, enum bpf_attach_type type, struct bpf_prog_array __rcu **array) { + enum bpf_cgroup_storage_type stype; struct bpf_prog_array *progs; struct bpf_prog_list *pl; struct cgroup *p = cgrp; @@ -125,7 +129,9 @@ static int compute_effective_progs(struct cgroup *cgrp, continue; progs->items[cnt].prog = pl->prog; - progs->items[cnt].cgroup_storage = pl->storage; + for_each_cgroup_storage_type(stype) + progs->items[cnt].cgroup_storage[stype] = + pl->storage[stype]; cnt++; } } while ((p = cgroup_parent(p))); @@ -232,7 +238,9 @@ int __cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog, { struct list_head *progs = &cgrp->bpf.progs[type]; struct bpf_prog *old_prog = NULL; - struct bpf_cgroup_storage *storage, *old_storage = NULL; + struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE], + *old_storage[MAX_BPF_CGROUP_STORAGE_TYPE] = {NULL}; + enum bpf_cgroup_storage_type stype; struct bpf_prog_list *pl; bool pl_was_allocated; int err; @@ -254,34 +262,44 @@ int __cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog, if (prog_list_length(progs) >= BPF_CGROUP_MAX_PROGS) return -E2BIG; - storage = bpf_cgroup_storage_alloc(prog); - if (IS_ERR(storage)) - return -ENOMEM; + for_each_cgroup_storage_type(stype) { + storage[stype] = bpf_cgroup_storage_alloc(prog, stype); + if (IS_ERR(storage[stype])) { + storage[stype] = NULL; + for_each_cgroup_storage_type(stype) + bpf_cgroup_storage_free(storage[stype]); + return -ENOMEM; + } + } if (flags & BPF_F_ALLOW_MULTI) { list_for_each_entry(pl, progs, node) { if (pl->prog == prog) { /* disallow attaching the same prog twice */ - bpf_cgroup_storage_free(storage); + for_each_cgroup_storage_type(stype) + bpf_cgroup_storage_free(storage[stype]); return -EINVAL; } } pl = kmalloc(sizeof(*pl), GFP_KERNEL); if (!pl) { - bpf_cgroup_storage_free(storage); + for_each_cgroup_storage_type(stype) + bpf_cgroup_storage_free(storage[stype]); return -ENOMEM; } pl_was_allocated = true; pl->prog = prog; - pl->storage = storage; + for_each_cgroup_storage_type(stype) + pl->storage[stype] = storage[stype]; list_add_tail(&pl->node, progs); } else { if (list_empty(progs)) { pl = kmalloc(sizeof(*pl), GFP_KERNEL); if (!pl) { - bpf_cgroup_storage_free(storage); + for_each_cgroup_storage_type(stype) + bpf_cgroup_storage_free(storage[stype]); return -ENOMEM; } pl_was_allocated = true; @@ -289,12 +307,15 @@ int __cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog, } else { pl = list_first_entry(progs, typeof(*pl), node); old_prog = pl->prog; - old_storage = pl->storage; - bpf_cgroup_storage_unlink(old_storage); + for_each_cgroup_storage_type(stype) { + old_storage[stype] = pl->storage[stype]; + bpf_cgroup_storage_unlink(old_storage[stype]); + } pl_was_allocated = false; } pl->prog = prog; - pl->storage = storage; + for_each_cgroup_storage_type(stype) + pl->storage[stype] = storage[stype]; } cgrp->bpf.flags[type] = flags; @@ -304,21 +325,27 @@ int __cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog, goto cleanup; static_branch_inc(&cgroup_bpf_enabled_key); - if (old_storage) - bpf_cgroup_storage_free(old_storage); + for_each_cgroup_storage_type(stype) { + if (!old_storage[stype]) + continue; + bpf_cgroup_storage_free(old_storage[stype]); + } if (old_prog) { bpf_prog_put(old_prog); static_branch_dec(&cgroup_bpf_enabled_key); } - bpf_cgroup_storage_link(storage, cgrp, type); + for_each_cgroup_storage_type(stype) + bpf_cgroup_storage_link(storage[stype], cgrp, type); return 0; cleanup: /* and cleanup the prog list */ pl->prog = old_prog; - bpf_cgroup_storage_free(pl->storage); - pl->storage = old_storage; - bpf_cgroup_storage_link(old_storage, cgrp, type); + for_each_cgroup_storage_type(stype) { + bpf_cgroup_storage_free(pl->storage[stype]); + pl->storage[stype] = old_storage[stype]; + bpf_cgroup_storage_link(old_storage[stype], cgrp, type); + } if (pl_was_allocated) { list_del(&pl->node); kfree(pl); @@ -339,6 +366,7 @@ int __cgroup_bpf_detach(struct cgroup *cgrp, struct bpf_prog *prog, enum bpf_attach_type type, u32 unused_flags) { struct list_head *progs = &cgrp->bpf.progs[type]; + enum bpf_cgroup_storage_type stype; u32 flags = cgrp->bpf.flags[type]; struct bpf_prog *old_prog = NULL; struct bpf_prog_list *pl; @@ -385,8 +413,10 @@ int __cgroup_bpf_detach(struct cgroup *cgrp, struct bpf_prog *prog, /* now can actually delete it from this cgroup list */ list_del(&pl->node); - bpf_cgroup_storage_unlink(pl->storage); - bpf_cgroup_storage_free(pl->storage); + for_each_cgroup_storage_type(stype) { + bpf_cgroup_storage_unlink(pl->storage[stype]); + bpf_cgroup_storage_free(pl->storage[stype]); + } kfree(pl); if (list_empty(progs)) /* last program was detached, reset flags to zero */ diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index 1991466b8327..9070b2ace6aa 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -194,16 +194,18 @@ const struct bpf_func_proto bpf_get_current_cgroup_id_proto = { .ret_type = RET_INTEGER, }; -DECLARE_PER_CPU(void*, bpf_cgroup_storage); +#ifdef CONFIG_CGROUP_BPF +DECLARE_PER_CPU(void*, bpf_cgroup_storage[MAX_BPF_CGROUP_STORAGE_TYPE]); BPF_CALL_2(bpf_get_local_storage, struct bpf_map *, map, u64, flags) { - /* map and flags arguments are not used now, - * but provide an ability to extend the API - * for other types of local storages. - * verifier checks that their values are correct. + /* flags argument is not used now, + * but provides an ability to extend the API. + * verifier checks that its value is correct. */ - return (unsigned long) this_cpu_read(bpf_cgroup_storage); + enum bpf_cgroup_storage_type stype = cgroup_storage_type(map); + + return (unsigned long) this_cpu_read(bpf_cgroup_storage[stype]); } const struct bpf_func_proto bpf_get_local_storage_proto = { @@ -214,3 +216,4 @@ const struct bpf_func_proto bpf_get_local_storage_proto = { .arg2_type = ARG_ANYTHING, }; #endif +#endif diff --git a/kernel/bpf/local_storage.c b/kernel/bpf/local_storage.c index 22ad967d1e5f..0bd9f19fc557 100644 --- a/kernel/bpf/local_storage.c +++ b/kernel/bpf/local_storage.c @@ -7,7 +7,7 @@ #include #include -DEFINE_PER_CPU(void*, bpf_cgroup_storage); +DEFINE_PER_CPU(void*, bpf_cgroup_storage[MAX_BPF_CGROUP_STORAGE_TYPE]); #ifdef CONFIG_CGROUP_BPF @@ -251,6 +251,7 @@ const struct bpf_map_ops cgroup_storage_map_ops = { int bpf_cgroup_storage_assign(struct bpf_prog *prog, struct bpf_map *_map) { + enum bpf_cgroup_storage_type stype = cgroup_storage_type(_map); struct bpf_cgroup_storage_map *map = map_to_storage(_map); int ret = -EBUSY; @@ -258,11 +259,12 @@ int bpf_cgroup_storage_assign(struct bpf_prog *prog, struct bpf_map *_map) if (map->prog && map->prog != prog) goto unlock; - if (prog->aux->cgroup_storage && prog->aux->cgroup_storage != _map) + if (prog->aux->cgroup_storage[stype] && + prog->aux->cgroup_storage[stype] != _map) goto unlock; map->prog = prog; - prog->aux->cgroup_storage = _map; + prog->aux->cgroup_storage[stype] = _map; ret = 0; unlock: spin_unlock_bh(&map->lock); @@ -272,24 +274,26 @@ unlock: void bpf_cgroup_storage_release(struct bpf_prog *prog, struct bpf_map *_map) { + enum bpf_cgroup_storage_type stype = cgroup_storage_type(_map); struct bpf_cgroup_storage_map *map = map_to_storage(_map); spin_lock_bh(&map->lock); if (map->prog == prog) { - WARN_ON(prog->aux->cgroup_storage != _map); + WARN_ON(prog->aux->cgroup_storage[stype] != _map); map->prog = NULL; - prog->aux->cgroup_storage = NULL; + prog->aux->cgroup_storage[stype] = NULL; } spin_unlock_bh(&map->lock); } -struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog) +struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog, + enum bpf_cgroup_storage_type stype) { struct bpf_cgroup_storage *storage; struct bpf_map *map; u32 pages; - map = prog->aux->cgroup_storage; + map = prog->aux->cgroup_storage[stype]; if (!map) return NULL; diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index b3c2d09bcf7a..8c91d2b41b1e 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -988,10 +988,15 @@ static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog) /* drop refcnt on maps used by eBPF program and free auxilary data */ static void free_used_maps(struct bpf_prog_aux *aux) { + enum bpf_cgroup_storage_type stype; int i; - if (aux->cgroup_storage) - bpf_cgroup_storage_release(aux->prog, aux->cgroup_storage); + for_each_cgroup_storage_type(stype) { + if (!aux->cgroup_storage[stype]) + continue; + bpf_cgroup_storage_release(aux->prog, + aux->cgroup_storage[stype]); + } for (i = 0; i < aux->used_map_cnt; i++) bpf_map_put(aux->used_maps[i]); diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index e986518d7bc3..e90899df585d 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -5171,11 +5171,15 @@ next_insn: /* drop refcnt of maps used by the rejected program */ static void release_maps(struct bpf_verifier_env *env) { + enum bpf_cgroup_storage_type stype; int i; - if (env->prog->aux->cgroup_storage) + for_each_cgroup_storage_type(stype) { + if (!env->prog->aux->cgroup_storage[stype]) + continue; bpf_cgroup_storage_release(env->prog, - env->prog->aux->cgroup_storage); + env->prog->aux->cgroup_storage[stype]); + } for (i = 0; i < env->used_map_cnt; i++) bpf_map_put(env->used_maps[i]); diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c index f4078830ea50..0c423b8cd75c 100644 --- a/net/bpf/test_run.c +++ b/net/bpf/test_run.c @@ -12,7 +12,7 @@ #include static __always_inline u32 bpf_test_run_one(struct bpf_prog *prog, void *ctx, - struct bpf_cgroup_storage *storage) + struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE]) { u32 ret; @@ -28,13 +28,20 @@ static __always_inline u32 bpf_test_run_one(struct bpf_prog *prog, void *ctx, static u32 bpf_test_run(struct bpf_prog *prog, void *ctx, u32 repeat, u32 *time) { - struct bpf_cgroup_storage *storage = NULL; + struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE] = { 0 }; + enum bpf_cgroup_storage_type stype; u64 time_start, time_spent = 0; u32 ret = 0, i; - storage = bpf_cgroup_storage_alloc(prog); - if (IS_ERR(storage)) - return PTR_ERR(storage); + for_each_cgroup_storage_type(stype) { + storage[stype] = bpf_cgroup_storage_alloc(prog, stype); + if (IS_ERR(storage[stype])) { + storage[stype] = NULL; + for_each_cgroup_storage_type(stype) + bpf_cgroup_storage_free(storage[stype]); + return -ENOMEM; + } + } if (!repeat) repeat = 1; @@ -53,7 +60,8 @@ static u32 bpf_test_run(struct bpf_prog *prog, void *ctx, u32 repeat, u32 *time) do_div(time_spent, repeat); *time = time_spent > U32_MAX ? U32_MAX : (u32)time_spent; - bpf_cgroup_storage_free(storage); + for_each_cgroup_storage_type(stype) + bpf_cgroup_storage_free(storage[stype]); return ret; } -- 2.30.2