From bae141f54be83b06652c1d47e50e4e75ed4e9c7e Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Fri, 6 Dec 2019 22:49:34 +0100 Subject: bpf: Emit audit messages upon successful prog load and unload Allow for audit messages to be emitted upon BPF program load and unload for having a timeline of events. The load itself is in syscall context, so additional info about the process initiating the BPF prog creation can be logged and later directly correlated to the unload event. The only info really needed from BPF side is the globally unique prog ID where then audit user space tooling can query / dump all info needed about the specific BPF program right upon load event and enrich the record, thus these changes needed here can be kept small and non-intrusive to the core. Raw example output: # auditctl -D # auditctl -a always,exit -F arch=x86_64 -S bpf # ausearch --start recent -m 1334 ... ---- time->Wed Nov 27 16:04:13 2019 type=PROCTITLE msg=audit(1574867053.120:84664): proctitle="./bpf" type=SYSCALL msg=audit(1574867053.120:84664): arch=c000003e syscall=321 \ success=yes exit=3 a0=5 a1=7ffea484fbe0 a2=70 a3=0 items=0 ppid=7477 \ pid=12698 auid=1001 uid=1001 gid=1001 euid=1001 suid=1001 fsuid=1001 \ egid=1001 sgid=1001 fsgid=1001 tty=pts2 ses=4 comm="bpf" \ exe="/home/jolsa/auditd/audit-testsuite/tests/bpf/bpf" \ subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 key=(null) type=UNKNOWN[1334] msg=audit(1574867053.120:84664): prog-id=76 op=LOAD ---- time->Wed Nov 27 16:04:13 2019 type=UNKNOWN[1334] msg=audit(1574867053.120:84665): prog-id=76 op=UNLOAD ... Signed-off-by: Daniel Borkmann Co-developed-by: Jiri Olsa Signed-off-by: Jiri Olsa Acked-by: Paul Moore Link: https://lore.kernel.org/bpf/20191206214934.11319-1-jolsa@kernel.org --- include/uapi/linux/audit.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/uapi/linux/audit.h b/include/uapi/linux/audit.h index 3ad935527177..a534d71e689a 100644 --- a/include/uapi/linux/audit.h +++ b/include/uapi/linux/audit.h @@ -116,6 +116,7 @@ #define AUDIT_FANOTIFY 1331 /* Fanotify access decision */ #define AUDIT_TIME_INJOFFSET 1332 /* Timekeeping offset injected */ #define AUDIT_TIME_ADJNTPVAL 1333 /* NTP value adjustment */ +#define AUDIT_BPF 1334 /* BPF subsystem */ #define AUDIT_AVC 1400 /* SE Linux avc denial or grant */ #define AUDIT_SELINUX_ERR 1401 /* Internal SE Linux Errors */ -- cgit v1.2.3 From 98e8627efcada18ac043a77b9101b4b4c768090b Mon Sep 17 00:00:00 2001 From: Björn Töpel Date: Fri, 13 Dec 2019 18:51:07 +0100 Subject: bpf: Move trampoline JIT image allocation to a function MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Refactor the image allocation in the BPF trampoline code into a separate function, so it can be shared with the BPF dispatcher in upcoming commits. Signed-off-by: Björn Töpel Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20191213175112.30208-2-bjorn.topel@gmail.com --- include/linux/bpf.h | 1 + kernel/bpf/trampoline.c | 24 +++++++++++++++++------- 2 files changed, 18 insertions(+), 7 deletions(-) (limited to 'include') diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 35903f148be5..5d744828b399 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -475,6 +475,7 @@ struct bpf_trampoline *bpf_trampoline_lookup(u64 key); int bpf_trampoline_link_prog(struct bpf_prog *prog); int bpf_trampoline_unlink_prog(struct bpf_prog *prog); void bpf_trampoline_put(struct bpf_trampoline *tr); +void *bpf_jit_alloc_exec_page(void); #else static inline struct bpf_trampoline *bpf_trampoline_lookup(u64 key) { diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c index 7e89f1f49d77..5ee301ddbd00 100644 --- a/kernel/bpf/trampoline.c +++ b/kernel/bpf/trampoline.c @@ -13,6 +13,22 @@ static struct hlist_head trampoline_table[TRAMPOLINE_TABLE_SIZE]; /* serializes access to trampoline_table */ static DEFINE_MUTEX(trampoline_mutex); +void *bpf_jit_alloc_exec_page(void) +{ + void *image; + + image = bpf_jit_alloc_exec(PAGE_SIZE); + if (!image) + return NULL; + + set_vm_flush_reset_perms(image); + /* Keep image as writeable. The alternative is to keep flipping ro/rw + * everytime new program is attached or detached. + */ + set_memory_x((long)image, 1); + return image; +} + struct bpf_trampoline *bpf_trampoline_lookup(u64 key) { struct bpf_trampoline *tr; @@ -33,7 +49,7 @@ struct bpf_trampoline *bpf_trampoline_lookup(u64 key) goto out; /* is_root was checked earlier. No need for bpf_jit_charge_modmem() */ - image = bpf_jit_alloc_exec(PAGE_SIZE); + image = bpf_jit_alloc_exec_page(); if (!image) { kfree(tr); tr = NULL; @@ -47,12 +63,6 @@ struct bpf_trampoline *bpf_trampoline_lookup(u64 key) mutex_init(&tr->mutex); for (i = 0; i < BPF_TRAMP_MAX; i++) INIT_HLIST_HEAD(&tr->progs_hlist[i]); - - set_vm_flush_reset_perms(image); - /* Keep image as writeable. The alternative is to keep flipping ro/rw - * everytime new program is attached or detached. - */ - set_memory_x((long)image, 1); tr->image = image; out: mutex_unlock(&trampoline_mutex); -- cgit v1.2.3 From 75ccbef6369e94ecac696a152a998a978d41376b Mon Sep 17 00:00:00 2001 From: Björn Töpel Date: Fri, 13 Dec 2019 18:51:08 +0100 Subject: bpf: Introduce BPF dispatcher MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The BPF dispatcher is a multi-way branch code generator, mainly targeted for XDP programs. When an XDP program is executed via the bpf_prog_run_xdp(), it is invoked via an indirect call. The indirect call has a substantial performance impact, when retpolines are enabled. The dispatcher transform indirect calls to direct calls, and therefore avoids the retpoline. The dispatcher is generated using the BPF JIT, and relies on text poking provided by bpf_arch_text_poke(). The dispatcher hijacks a trampoline function it via the __fentry__ nop of the trampoline. One dispatcher instance currently supports up to 64 dispatch points. A user creates a dispatcher with its corresponding trampoline with the DEFINE_BPF_DISPATCHER macro. Signed-off-by: Björn Töpel Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20191213175112.30208-3-bjorn.topel@gmail.com --- arch/x86/net/bpf_jit_comp.c | 122 ++++++++++++++++++++++++++++++++++ include/linux/bpf.h | 56 ++++++++++++++++ kernel/bpf/Makefile | 1 + kernel/bpf/dispatcher.c | 158 ++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 337 insertions(+) create mode 100644 kernel/bpf/dispatcher.c (limited to 'include') diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index b8be18427277..3ce7ad41bd6f 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -10,10 +10,12 @@ #include #include #include +#include #include #include #include #include +#include static u8 *emit_code(u8 *ptr, u32 bytes, unsigned int len) { @@ -1530,6 +1532,126 @@ int arch_prepare_bpf_trampoline(void *image, struct btf_func_model *m, u32 flags return 0; } +static int emit_cond_near_jump(u8 **pprog, void *func, void *ip, u8 jmp_cond) +{ + u8 *prog = *pprog; + int cnt = 0; + s64 offset; + + offset = func - (ip + 2 + 4); + if (!is_simm32(offset)) { + pr_err("Target %p is out of range\n", func); + return -EINVAL; + } + EMIT2_off32(0x0F, jmp_cond + 0x10, offset); + *pprog = prog; + return 0; +} + +static int emit_fallback_jump(u8 **pprog) +{ + u8 *prog = *pprog; + int err = 0; + +#ifdef CONFIG_RETPOLINE + /* Note that this assumes the the compiler uses external + * thunks for indirect calls. Both clang and GCC use the same + * naming convention for external thunks. + */ + err = emit_jump(&prog, __x86_indirect_thunk_rdx, prog); +#else + int cnt = 0; + + EMIT2(0xFF, 0xE2); /* jmp rdx */ +#endif + *pprog = prog; + return err; +} + +static int emit_bpf_dispatcher(u8 **pprog, int a, int b, s64 *progs) +{ + int pivot, err, jg_bytes = 1, cnt = 0; + u8 *jg_reloc, *prog = *pprog; + s64 jg_offset; + + if (a == b) { + /* Leaf node of recursion, i.e. not a range of indices + * anymore. + */ + EMIT1(add_1mod(0x48, BPF_REG_3)); /* cmp rdx,func */ + if (!is_simm32(progs[a])) + return -1; + EMIT2_off32(0x81, add_1reg(0xF8, BPF_REG_3), + progs[a]); + err = emit_cond_near_jump(&prog, /* je func */ + (void *)progs[a], prog, + X86_JE); + if (err) + return err; + + err = emit_fallback_jump(&prog); /* jmp thunk/indirect */ + if (err) + return err; + + *pprog = prog; + return 0; + } + + /* Not a leaf node, so we pivot, and recursively descend into + * the lower and upper ranges. + */ + pivot = (b - a) / 2; + EMIT1(add_1mod(0x48, BPF_REG_3)); /* cmp rdx,func */ + if (!is_simm32(progs[a + pivot])) + return -1; + EMIT2_off32(0x81, add_1reg(0xF8, BPF_REG_3), progs[a + pivot]); + + if (pivot > 2) { /* jg upper_part */ + /* Require near jump. */ + jg_bytes = 4; + EMIT2_off32(0x0F, X86_JG + 0x10, 0); + } else { + EMIT2(X86_JG, 0); + } + jg_reloc = prog; + + err = emit_bpf_dispatcher(&prog, a, a + pivot, /* emit lower_part */ + progs); + if (err) + return err; + + jg_offset = prog - jg_reloc; + emit_code(jg_reloc - jg_bytes, jg_offset, jg_bytes); + + err = emit_bpf_dispatcher(&prog, a + pivot + 1, /* emit upper_part */ + b, progs); + if (err) + return err; + + *pprog = prog; + return 0; +} + +static int cmp_ips(const void *a, const void *b) +{ + const s64 *ipa = a; + const s64 *ipb = b; + + if (*ipa > *ipb) + return 1; + if (*ipa < *ipb) + return -1; + return 0; +} + +int arch_prepare_bpf_dispatcher(void *image, s64 *funcs, int num_funcs) +{ + u8 *prog = image; + + sort(funcs, num_funcs, sizeof(funcs[0]), cmp_ips, NULL); + return emit_bpf_dispatcher(&prog, 0, num_funcs - 1, funcs); +} + struct x64_jit_data { struct bpf_binary_header *header; int *addrs; diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 5d744828b399..53ae4a50abe4 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -470,12 +470,61 @@ struct bpf_trampoline { void *image; u64 selector; }; + +#define BPF_DISPATCHER_MAX 64 /* Fits in 2048B */ + +struct bpf_dispatcher_prog { + struct bpf_prog *prog; + refcount_t users; +}; + +struct bpf_dispatcher { + /* dispatcher mutex */ + struct mutex mutex; + void *func; + struct bpf_dispatcher_prog progs[BPF_DISPATCHER_MAX]; + int num_progs; + void *image; + u32 image_off; +}; + #ifdef CONFIG_BPF_JIT struct bpf_trampoline *bpf_trampoline_lookup(u64 key); int bpf_trampoline_link_prog(struct bpf_prog *prog); int bpf_trampoline_unlink_prog(struct bpf_prog *prog); void bpf_trampoline_put(struct bpf_trampoline *tr); void *bpf_jit_alloc_exec_page(void); +#define BPF_DISPATCHER_INIT(name) { \ + .mutex = __MUTEX_INITIALIZER(name.mutex), \ + .func = &name##func, \ + .progs = {}, \ + .num_progs = 0, \ + .image = NULL, \ + .image_off = 0 \ +} + +#define DEFINE_BPF_DISPATCHER(name) \ + noinline unsigned int name##func( \ + const void *ctx, \ + const struct bpf_insn *insnsi, \ + unsigned int (*bpf_func)(const void *, \ + const struct bpf_insn *)) \ + { \ + return bpf_func(ctx, insnsi); \ + } \ + EXPORT_SYMBOL(name##func); \ + struct bpf_dispatcher name = BPF_DISPATCHER_INIT(name); +#define DECLARE_BPF_DISPATCHER(name) \ + unsigned int name##func( \ + const void *ctx, \ + const struct bpf_insn *insnsi, \ + unsigned int (*bpf_func)(const void *, \ + const struct bpf_insn *)); \ + extern struct bpf_dispatcher name; +#define BPF_DISPATCHER_FUNC(name) name##func +#define BPF_DISPATCHER_PTR(name) (&name) +void bpf_dispatcher_change_prog(struct bpf_dispatcher *d, struct bpf_prog *from, + struct bpf_prog *to); #else static inline struct bpf_trampoline *bpf_trampoline_lookup(u64 key) { @@ -490,6 +539,13 @@ static inline int bpf_trampoline_unlink_prog(struct bpf_prog *prog) return -ENOTSUPP; } static inline void bpf_trampoline_put(struct bpf_trampoline *tr) {} +#define DEFINE_BPF_DISPATCHER(name) +#define DECLARE_BPF_DISPATCHER(name) +#define BPF_DISPATCHER_FUNC(name) bpf_dispatcher_nopfunc +#define BPF_DISPATCHER_PTR(name) NULL +static inline void bpf_dispatcher_change_prog(struct bpf_dispatcher *d, + struct bpf_prog *from, + struct bpf_prog *to) {} #endif struct bpf_func_info_aux { diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile index 3f671bf617e8..d4f330351f87 100644 --- a/kernel/bpf/Makefile +++ b/kernel/bpf/Makefile @@ -8,6 +8,7 @@ obj-$(CONFIG_BPF_SYSCALL) += local_storage.o queue_stack_maps.o obj-$(CONFIG_BPF_SYSCALL) += disasm.o obj-$(CONFIG_BPF_JIT) += trampoline.o obj-$(CONFIG_BPF_SYSCALL) += btf.o +obj-$(CONFIG_BPF_JIT) += dispatcher.o ifeq ($(CONFIG_NET),y) obj-$(CONFIG_BPF_SYSCALL) += devmap.o obj-$(CONFIG_BPF_SYSCALL) += cpumap.o diff --git a/kernel/bpf/dispatcher.c b/kernel/bpf/dispatcher.c new file mode 100644 index 000000000000..204ee61a3904 --- /dev/null +++ b/kernel/bpf/dispatcher.c @@ -0,0 +1,158 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright(c) 2019 Intel Corporation. */ + +#include +#include +#include + +/* The BPF dispatcher is a multiway branch code generator. The + * dispatcher is a mechanism to avoid the performance penalty of an + * indirect call, which is expensive when retpolines are enabled. A + * dispatch client registers a BPF program into the dispatcher, and if + * there is available room in the dispatcher a direct call to the BPF + * program will be generated. All calls to the BPF programs called via + * the dispatcher will then be a direct call, instead of an + * indirect. The dispatcher hijacks a trampoline function it via the + * __fentry__ of the trampoline. The trampoline function has the + * following signature: + * + * unsigned int trampoline(const void *ctx, const struct bpf_insn *insnsi, + * unsigned int (*bpf_func)(const void *, + * const struct bpf_insn *)); + */ + +static struct bpf_dispatcher_prog *bpf_dispatcher_find_prog( + struct bpf_dispatcher *d, struct bpf_prog *prog) +{ + int i; + + for (i = 0; i < BPF_DISPATCHER_MAX; i++) { + if (prog == d->progs[i].prog) + return &d->progs[i]; + } + return NULL; +} + +static struct bpf_dispatcher_prog *bpf_dispatcher_find_free( + struct bpf_dispatcher *d) +{ + return bpf_dispatcher_find_prog(d, NULL); +} + +static bool bpf_dispatcher_add_prog(struct bpf_dispatcher *d, + struct bpf_prog *prog) +{ + struct bpf_dispatcher_prog *entry; + + if (!prog) + return false; + + entry = bpf_dispatcher_find_prog(d, prog); + if (entry) { + refcount_inc(&entry->users); + return false; + } + + entry = bpf_dispatcher_find_free(d); + if (!entry) + return false; + + bpf_prog_inc(prog); + entry->prog = prog; + refcount_set(&entry->users, 1); + d->num_progs++; + return true; +} + +static bool bpf_dispatcher_remove_prog(struct bpf_dispatcher *d, + struct bpf_prog *prog) +{ + struct bpf_dispatcher_prog *entry; + + if (!prog) + return false; + + entry = bpf_dispatcher_find_prog(d, prog); + if (!entry) + return false; + + if (refcount_dec_and_test(&entry->users)) { + entry->prog = NULL; + bpf_prog_put(prog); + d->num_progs--; + return true; + } + return false; +} + +int __weak arch_prepare_bpf_dispatcher(void *image, s64 *funcs, int num_funcs) +{ + return -ENOTSUPP; +} + +static int bpf_dispatcher_prepare(struct bpf_dispatcher *d, void *image) +{ + s64 ips[BPF_DISPATCHER_MAX] = {}, *ipsp = &ips[0]; + int i; + + for (i = 0; i < BPF_DISPATCHER_MAX; i++) { + if (d->progs[i].prog) + *ipsp++ = (s64)(uintptr_t)d->progs[i].prog->bpf_func; + } + return arch_prepare_bpf_dispatcher(image, &ips[0], d->num_progs); +} + +static void bpf_dispatcher_update(struct bpf_dispatcher *d, int prev_num_progs) +{ + void *old, *new; + u32 noff; + int err; + + if (!prev_num_progs) { + old = NULL; + noff = 0; + } else { + old = d->image + d->image_off; + noff = d->image_off ^ (PAGE_SIZE / 2); + } + + new = d->num_progs ? d->image + noff : NULL; + if (new) { + if (bpf_dispatcher_prepare(d, new)) + return; + } + + err = bpf_arch_text_poke(d->func, BPF_MOD_JUMP, old, new); + if (err || !new) + return; + + d->image_off = noff; +} + +void bpf_dispatcher_change_prog(struct bpf_dispatcher *d, struct bpf_prog *from, + struct bpf_prog *to) +{ + bool changed = false; + int prev_num_progs; + + if (from == to) + return; + + mutex_lock(&d->mutex); + if (!d->image) { + d->image = bpf_jit_alloc_exec_page(); + if (!d->image) + goto out; + } + + prev_num_progs = d->num_progs; + changed |= bpf_dispatcher_remove_prog(d, from); + changed |= bpf_dispatcher_add_prog(d, to); + + if (!changed) + goto out; + + bpf_dispatcher_update(d, prev_num_progs); +out: + mutex_unlock(&d->mutex); +} -- cgit v1.2.3 From 7e6897f95935973c3253fd756135b5ea58043dc8 Mon Sep 17 00:00:00 2001 From: Björn Töpel Date: Fri, 13 Dec 2019 18:51:09 +0100 Subject: bpf, xdp: Start using the BPF dispatcher for XDP MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This commit adds a BPF dispatcher for XDP. The dispatcher is updated from the XDP control-path, dev_xdp_install(), and used when an XDP program is run via bpf_prog_run_xdp(). Signed-off-by: Björn Töpel Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20191213175112.30208-4-bjorn.topel@gmail.com --- include/linux/bpf.h | 15 +++++++++++++++ include/linux/filter.h | 40 ++++++++++++++++++++++++---------------- kernel/bpf/syscall.c | 26 ++++++++++++++++++-------- net/core/dev.c | 19 ++++++++++++++++++- net/core/filter.c | 8 ++++++++ 5 files changed, 83 insertions(+), 25 deletions(-) (limited to 'include') diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 53ae4a50abe4..5970989b99d1 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -488,6 +488,14 @@ struct bpf_dispatcher { u32 image_off; }; +static __always_inline unsigned int bpf_dispatcher_nopfunc( + const void *ctx, + const struct bpf_insn *insnsi, + unsigned int (*bpf_func)(const void *, + const struct bpf_insn *)) +{ + return bpf_func(ctx, insnsi); +} #ifdef CONFIG_BPF_JIT struct bpf_trampoline *bpf_trampoline_lookup(u64 key); int bpf_trampoline_link_prog(struct bpf_prog *prog); @@ -997,6 +1005,8 @@ int btf_distill_func_proto(struct bpf_verifier_log *log, int btf_check_func_arg_match(struct bpf_verifier_env *env, int subprog); +struct bpf_prog *bpf_prog_by_id(u32 id); + #else /* !CONFIG_BPF_SYSCALL */ static inline struct bpf_prog *bpf_prog_get(u32 ufd) { @@ -1128,6 +1138,11 @@ static inline int bpf_prog_test_run_flow_dissector(struct bpf_prog *prog, static inline void bpf_map_put(struct bpf_map *map) { } + +static inline struct bpf_prog *bpf_prog_by_id(u32 id) +{ + return ERR_PTR(-ENOTSUPP); +} #endif /* CONFIG_BPF_SYSCALL */ static inline struct bpf_prog *bpf_prog_get_type(u32 ufd, diff --git a/include/linux/filter.h b/include/linux/filter.h index a141cb07e76a..37ac7025031d 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -559,23 +559,26 @@ struct sk_filter { DECLARE_STATIC_KEY_FALSE(bpf_stats_enabled_key); -#define BPF_PROG_RUN(prog, ctx) ({ \ - u32 ret; \ - cant_sleep(); \ - if (static_branch_unlikely(&bpf_stats_enabled_key)) { \ - struct bpf_prog_stats *stats; \ - u64 start = sched_clock(); \ - ret = (*(prog)->bpf_func)(ctx, (prog)->insnsi); \ - stats = this_cpu_ptr(prog->aux->stats); \ - u64_stats_update_begin(&stats->syncp); \ - stats->cnt++; \ - stats->nsecs += sched_clock() - start; \ - u64_stats_update_end(&stats->syncp); \ - } else { \ - ret = (*(prog)->bpf_func)(ctx, (prog)->insnsi); \ - } \ +#define __BPF_PROG_RUN(prog, ctx, dfunc) ({ \ + u32 ret; \ + cant_sleep(); \ + if (static_branch_unlikely(&bpf_stats_enabled_key)) { \ + struct bpf_prog_stats *stats; \ + u64 start = sched_clock(); \ + ret = dfunc(ctx, (prog)->insnsi, (prog)->bpf_func); \ + stats = this_cpu_ptr(prog->aux->stats); \ + u64_stats_update_begin(&stats->syncp); \ + stats->cnt++; \ + stats->nsecs += sched_clock() - start; \ + u64_stats_update_end(&stats->syncp); \ + } else { \ + ret = dfunc(ctx, (prog)->insnsi, (prog)->bpf_func); \ + } \ ret; }) +#define BPF_PROG_RUN(prog, ctx) __BPF_PROG_RUN(prog, ctx, \ + bpf_dispatcher_nopfunc) + #define BPF_SKB_CB_LEN QDISC_CB_PRIV_LEN struct bpf_skb_data_end { @@ -699,6 +702,8 @@ static inline u32 bpf_prog_run_clear_cb(const struct bpf_prog *prog, return res; } +DECLARE_BPF_DISPATCHER(bpf_dispatcher_xdp) + static __always_inline u32 bpf_prog_run_xdp(const struct bpf_prog *prog, struct xdp_buff *xdp) { @@ -708,9 +713,12 @@ static __always_inline u32 bpf_prog_run_xdp(const struct bpf_prog *prog, * already takes rcu_read_lock() when fetching the program, so * it's not necessary here anymore. */ - return BPF_PROG_RUN(prog, xdp); + return __BPF_PROG_RUN(prog, xdp, + BPF_DISPATCHER_FUNC(bpf_dispatcher_xdp)); } +void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog); + static inline u32 bpf_prog_insn_size(const struct bpf_prog *prog) { return prog->len * sizeof(struct bpf_insn); diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 66b90eaf99fe..b08c362f4e02 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -2338,17 +2338,12 @@ static int bpf_obj_get_next_id(const union bpf_attr *attr, #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id -static int bpf_prog_get_fd_by_id(const union bpf_attr *attr) +struct bpf_prog *bpf_prog_by_id(u32 id) { struct bpf_prog *prog; - u32 id = attr->prog_id; - int fd; - - if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID)) - return -EINVAL; - if (!capable(CAP_SYS_ADMIN)) - return -EPERM; + if (!id) + return ERR_PTR(-ENOENT); spin_lock_bh(&prog_idr_lock); prog = idr_find(&prog_idr, id); @@ -2357,7 +2352,22 @@ static int bpf_prog_get_fd_by_id(const union bpf_attr *attr) else prog = ERR_PTR(-ENOENT); spin_unlock_bh(&prog_idr_lock); + return prog; +} + +static int bpf_prog_get_fd_by_id(const union bpf_attr *attr) +{ + struct bpf_prog *prog; + u32 id = attr->prog_id; + int fd; + + if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID)) + return -EINVAL; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + prog = bpf_prog_by_id(id); if (IS_ERR(prog)) return PTR_ERR(prog); diff --git a/net/core/dev.c b/net/core/dev.c index 2c277b8aba38..255d3cf35360 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -8542,7 +8542,17 @@ static int dev_xdp_install(struct net_device *dev, bpf_op_t bpf_op, struct netlink_ext_ack *extack, u32 flags, struct bpf_prog *prog) { + bool non_hw = !(flags & XDP_FLAGS_HW_MODE); + struct bpf_prog *prev_prog = NULL; struct netdev_bpf xdp; + int err; + + if (non_hw) { + prev_prog = bpf_prog_by_id(__dev_xdp_query(dev, bpf_op, + XDP_QUERY_PROG)); + if (IS_ERR(prev_prog)) + prev_prog = NULL; + } memset(&xdp, 0, sizeof(xdp)); if (flags & XDP_FLAGS_HW_MODE) @@ -8553,7 +8563,14 @@ static int dev_xdp_install(struct net_device *dev, bpf_op_t bpf_op, xdp.flags = flags; xdp.prog = prog; - return bpf_op(dev, &xdp); + err = bpf_op(dev, &xdp); + if (!err && non_hw) + bpf_prog_change_xdp(prev_prog, prog); + + if (prev_prog) + bpf_prog_put(prev_prog); + + return err; } static void dev_xdp_uninstall(struct net_device *dev) diff --git a/net/core/filter.c b/net/core/filter.c index f1e703eed3d2..a411f7835dee 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -8940,3 +8940,11 @@ const struct bpf_verifier_ops sk_reuseport_verifier_ops = { const struct bpf_prog_ops sk_reuseport_prog_ops = { }; #endif /* CONFIG_INET */ + +DEFINE_BPF_DISPATCHER(bpf_dispatcher_xdp) + +void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog) +{ + bpf_dispatcher_change_prog(BPF_DISPATCHER_PTR(bpf_dispatcher_xdp), + prev_prog, prog); +} -- cgit v1.2.3 From 116eb788f57c9c35c40b29cfaa2607020de99a84 Mon Sep 17 00:00:00 2001 From: Björn Töpel Date: Fri, 13 Dec 2019 18:51:12 +0100 Subject: bpf, x86: Align dispatcher branch targets to 16B MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit >From Intel 64 and IA-32 Architectures Optimization Reference Manual, 3.4.1.4 Code Alignment, Assembly/Compiler Coding Rule 11: All branch targets should be 16-byte aligned. This commits aligns branch targets according to the Intel manual. The nops used to align branch targets make the dispatcher larger, and therefore the number of supported dispatch points/programs are descreased from 64 to 48. Signed-off-by: Björn Töpel Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20191213175112.30208-7-bjorn.topel@gmail.com --- arch/x86/net/bpf_jit_comp.c | 30 +++++++++++++++++++++++++++++- include/linux/bpf.h | 2 +- 2 files changed, 30 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index 3ce7ad41bd6f..4c8a2d1f8470 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -1548,6 +1548,26 @@ static int emit_cond_near_jump(u8 **pprog, void *func, void *ip, u8 jmp_cond) return 0; } +static void emit_nops(u8 **pprog, unsigned int len) +{ + unsigned int i, noplen; + u8 *prog = *pprog; + int cnt = 0; + + while (len > 0) { + noplen = len; + + if (noplen > ASM_NOP_MAX) + noplen = ASM_NOP_MAX; + + for (i = 0; i < noplen; i++) + EMIT1(ideal_nops[noplen][i]); + len -= noplen; + } + + *pprog = prog; +} + static int emit_fallback_jump(u8 **pprog) { u8 *prog = *pprog; @@ -1570,8 +1590,8 @@ static int emit_fallback_jump(u8 **pprog) static int emit_bpf_dispatcher(u8 **pprog, int a, int b, s64 *progs) { + u8 *jg_reloc, *jg_target, *prog = *pprog; int pivot, err, jg_bytes = 1, cnt = 0; - u8 *jg_reloc, *prog = *pprog; s64 jg_offset; if (a == b) { @@ -1620,6 +1640,14 @@ static int emit_bpf_dispatcher(u8 **pprog, int a, int b, s64 *progs) if (err) return err; + /* From Intel 64 and IA-32 Architectures Optimization + * Reference Manual, 3.4.1.4 Code Alignment, Assembly/Compiler + * Coding Rule 11: All branch targets should be 16-byte + * aligned. + */ + jg_target = PTR_ALIGN(prog, 16); + if (jg_target != prog) + emit_nops(&prog, jg_target - prog); jg_offset = prog - jg_reloc; emit_code(jg_reloc - jg_bytes, jg_offset, jg_bytes); diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 5970989b99d1..d467983e61bb 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -471,7 +471,7 @@ struct bpf_trampoline { u64 selector; }; -#define BPF_DISPATCHER_MAX 64 /* Fits in 2048B */ +#define BPF_DISPATCHER_MAX 48 /* Fits in 2048B */ struct bpf_dispatcher_prog { struct bpf_prog *prog; -- cgit v1.2.3 From 166750bc1dd256b2184b22588fb9fe6d3fbb93ae Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Fri, 13 Dec 2019 17:47:08 -0800 Subject: libbpf: Support libbpf-provided extern variables Add support for extern variables, provided to BPF program by libbpf. Currently the following extern variables are supported: - LINUX_KERNEL_VERSION; version of a kernel in which BPF program is executing, follows KERNEL_VERSION() macro convention, can be 4- and 8-byte long; - CONFIG_xxx values; a set of values of actual kernel config. Tristate, boolean, strings, and integer values are supported. Set of possible values is determined by declared type of extern variable. Supported types of variables are: - Tristate values. Are represented as `enum libbpf_tristate`. Accepted values are **strictly** 'y', 'n', or 'm', which are represented as TRI_YES, TRI_NO, or TRI_MODULE, respectively. - Boolean values. Are represented as bool (_Bool) types. Accepted values are 'y' and 'n' only, turning into true/false values, respectively. - Single-character values. Can be used both as a substritute for bool/tristate, or as a small-range integer: - 'y'/'n'/'m' are represented as is, as characters 'y', 'n', or 'm'; - integers in a range [-128, 127] or [0, 255] (depending on signedness of char in target architecture) are recognized and represented with respective values of char type. - Strings. String values are declared as fixed-length char arrays. String of up to that length will be accepted and put in first N bytes of char array, with the rest of bytes zeroed out. If config string value is longer than space alloted, it will be truncated and warning message emitted. Char array is always zero terminated. String literals in config have to be enclosed in double quotes, just like C-style string literals. - Integers. 8-, 16-, 32-, and 64-bit integers are supported, both signed and unsigned variants. Libbpf enforces parsed config value to be in the supported range of corresponding integer type. Integers values in config can be: - decimal integers, with optional + and - signs; - hexadecimal integers, prefixed with 0x or 0X; - octal integers, starting with 0. Config file itself is searched in /boot/config-$(uname -r) location with fallback to /proc/config.gz, unless config path is specified explicitly through bpf_object_open_opts' kernel_config_path option. Both gzipped and plain text formats are supported. Libbpf adds explicit dependency on zlib because of this, but this shouldn't be a problem, given libelf already depends on zlib. All detected extern variables, are put into a separate .extern internal map. It, similarly to .rodata map, is marked as read-only from BPF program side, as well as is frozen on load. This allows BPF verifier to track extern values as constants and perform enhanced branch prediction and dead code elimination. This can be relied upon for doing kernel version/feature detection and using potentially unsupported field relocations or BPF helpers in a CO-RE-based BPF program, while still having a single version of BPF program running on old and new kernels. Selftests are validating this explicitly for unexisting BPF helper. Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20191214014710.3449601-3-andriin@fb.com --- include/uapi/linux/btf.h | 3 +- tools/include/uapi/linux/btf.h | 7 +- tools/lib/bpf/Makefile | 15 +- tools/lib/bpf/bpf_helpers.h | 9 + tools/lib/bpf/btf.c | 9 +- tools/lib/bpf/libbpf.c | 738 ++++++++++++++++++++++++++++++++--- tools/lib/bpf/libbpf.h | 12 +- tools/testing/selftests/bpf/Makefile | 2 +- 8 files changed, 729 insertions(+), 66 deletions(-) (limited to 'include') diff --git a/include/uapi/linux/btf.h b/include/uapi/linux/btf.h index c02dec97e1ce..1a2898c482ee 100644 --- a/include/uapi/linux/btf.h +++ b/include/uapi/linux/btf.h @@ -142,7 +142,8 @@ struct btf_param { enum { BTF_VAR_STATIC = 0, - BTF_VAR_GLOBAL_ALLOCATED, + BTF_VAR_GLOBAL_ALLOCATED = 1, + BTF_VAR_GLOBAL_EXTERN = 2, }; /* BTF_KIND_VAR is followed by a single "struct btf_var" to describe diff --git a/tools/include/uapi/linux/btf.h b/tools/include/uapi/linux/btf.h index 63ae4a39e58b..1a2898c482ee 100644 --- a/tools/include/uapi/linux/btf.h +++ b/tools/include/uapi/linux/btf.h @@ -22,9 +22,9 @@ struct btf_header { }; /* Max # of type identifier */ -#define BTF_MAX_TYPE 0x0000ffff +#define BTF_MAX_TYPE 0x000fffff /* Max offset into the string section */ -#define BTF_MAX_NAME_OFFSET 0x0000ffff +#define BTF_MAX_NAME_OFFSET 0x00ffffff /* Max # of struct/union/enum members or func args */ #define BTF_MAX_VLEN 0xffff @@ -142,7 +142,8 @@ struct btf_param { enum { BTF_VAR_STATIC = 0, - BTF_VAR_GLOBAL_ALLOCATED, + BTF_VAR_GLOBAL_ALLOCATED = 1, + BTF_VAR_GLOBAL_EXTERN = 2, }; /* BTF_KIND_VAR is followed by a single "struct btf_var" to describe diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile index 23ae06c43d08..a3718cb275f2 100644 --- a/tools/lib/bpf/Makefile +++ b/tools/lib/bpf/Makefile @@ -56,8 +56,8 @@ ifndef VERBOSE endif FEATURE_USER = .libbpf -FEATURE_TESTS = libelf libelf-mmap bpf reallocarray -FEATURE_DISPLAY = libelf bpf +FEATURE_TESTS = libelf libelf-mmap zlib bpf reallocarray +FEATURE_DISPLAY = libelf zlib bpf INCLUDES = -I. -I$(srctree)/tools/include -I$(srctree)/tools/arch/$(ARCH)/include/uapi -I$(srctree)/tools/include/uapi FEATURE_CHECK_CFLAGS-bpf = $(INCLUDES) @@ -160,7 +160,7 @@ all: fixdep all_cmd: $(CMD_TARGETS) check -$(BPF_IN_SHARED): force elfdep bpfdep bpf_helper_defs.h +$(BPF_IN_SHARED): force elfdep zdep bpfdep bpf_helper_defs.h @(test -f ../../include/uapi/linux/bpf.h -a -f ../../../include/uapi/linux/bpf.h && ( \ (diff -B ../../include/uapi/linux/bpf.h ../../../include/uapi/linux/bpf.h >/dev/null) || \ echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/bpf.h' differs from latest version at 'include/uapi/linux/bpf.h'" >&2 )) || true @@ -178,7 +178,7 @@ $(BPF_IN_SHARED): force elfdep bpfdep bpf_helper_defs.h echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/if_xdp.h' differs from latest version at 'include/uapi/linux/if_xdp.h'" >&2 )) || true $(Q)$(MAKE) $(build)=libbpf OUTPUT=$(SHARED_OBJDIR) CFLAGS="$(CFLAGS) $(SHLIB_FLAGS)" -$(BPF_IN_STATIC): force elfdep bpfdep bpf_helper_defs.h +$(BPF_IN_STATIC): force elfdep zdep bpfdep bpf_helper_defs.h $(Q)$(MAKE) $(build)=libbpf OUTPUT=$(STATIC_OBJDIR) bpf_helper_defs.h: $(srctree)/tools/include/uapi/linux/bpf.h @@ -190,7 +190,7 @@ $(OUTPUT)libbpf.so: $(OUTPUT)libbpf.so.$(LIBBPF_VERSION) $(OUTPUT)libbpf.so.$(LIBBPF_VERSION): $(BPF_IN_SHARED) $(QUIET_LINK)$(CC) $(LDFLAGS) \ --shared -Wl,-soname,libbpf.so.$(LIBBPF_MAJOR_VERSION) \ - -Wl,--version-script=$(VERSION_SCRIPT) $^ -lelf -o $@ + -Wl,--version-script=$(VERSION_SCRIPT) $^ -lelf -lz -o $@ @ln -sf $(@F) $(OUTPUT)libbpf.so @ln -sf $(@F) $(OUTPUT)libbpf.so.$(LIBBPF_MAJOR_VERSION) @@ -279,12 +279,15 @@ clean: -PHONY += force elfdep bpfdep cscope tags +PHONY += force elfdep zdep bpfdep cscope tags force: elfdep: @if [ "$(feature-libelf)" != "1" ]; then echo "No libelf found"; exit 1 ; fi +zdep: + @if [ "$(feature-zlib)" != "1" ]; then echo "No zlib found"; exit 1 ; fi + bpfdep: @if [ "$(feature-bpf)" != "1" ]; then echo "BPF API too old"; exit 1 ; fi diff --git a/tools/lib/bpf/bpf_helpers.h b/tools/lib/bpf/bpf_helpers.h index 0c7d28292898..aa46700075e1 100644 --- a/tools/lib/bpf/bpf_helpers.h +++ b/tools/lib/bpf/bpf_helpers.h @@ -25,6 +25,9 @@ #ifndef __always_inline #define __always_inline __attribute__((always_inline)) #endif +#ifndef __weak +#define __weak __attribute__((weak)) +#endif /* * Helper structure used by eBPF C program @@ -44,4 +47,10 @@ enum libbpf_pin_type { LIBBPF_PIN_BY_NAME, }; +enum libbpf_tristate { + TRI_NO = 0, + TRI_YES = 1, + TRI_MODULE = 2, +}; + #endif diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c index 84fe82f27bef..520021939d81 100644 --- a/tools/lib/bpf/btf.c +++ b/tools/lib/bpf/btf.c @@ -578,6 +578,12 @@ static int btf_fixup_datasec(struct bpf_object *obj, struct btf *btf, return -ENOENT; } + /* .extern datasec size and var offsets were set correctly during + * extern collection step, so just skip straight to sorting variables + */ + if (t->size) + goto sort_vars; + ret = bpf_object__section_size(obj, name, &size); if (ret || !size || (t->size && t->size != size)) { pr_debug("Invalid size for section %s: %u bytes\n", name, size); @@ -614,7 +620,8 @@ static int btf_fixup_datasec(struct bpf_object *obj, struct btf *btf, vsi->offset = off; } - qsort(t + 1, vars, sizeof(*vsi), compare_vsi_off); +sort_vars: + qsort(btf_var_secinfos(t), vars, sizeof(*vsi), compare_vsi_off); return 0; } diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index f6c135869701..26144706ba0b 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -44,6 +44,7 @@ #include #include #include +#include #include "libbpf.h" #include "bpf.h" @@ -139,6 +140,20 @@ struct bpf_capabilities { __u32 array_mmap:1; }; +enum reloc_type { + RELO_LD64, + RELO_CALL, + RELO_DATA, + RELO_EXTERN, +}; + +struct reloc_desc { + enum reloc_type type; + int insn_idx; + int map_idx; + int sym_off; +}; + /* * bpf_prog should be a better name but it has been used in * linux/filter.h. @@ -157,16 +172,7 @@ struct bpf_program { size_t insns_cnt, main_prog_cnt; enum bpf_prog_type type; - struct reloc_desc { - enum { - RELO_LD64, - RELO_CALL, - RELO_DATA, - } type; - int insn_idx; - int map_idx; - int sym_off; - } *reloc_desc; + struct reloc_desc *reloc_desc; int nr_reloc; int log_level; @@ -198,18 +204,21 @@ struct bpf_program { #define DATA_SEC ".data" #define BSS_SEC ".bss" #define RODATA_SEC ".rodata" +#define EXTERN_SEC ".extern" enum libbpf_map_type { LIBBPF_MAP_UNSPEC, LIBBPF_MAP_DATA, LIBBPF_MAP_BSS, LIBBPF_MAP_RODATA, + LIBBPF_MAP_EXTERN, }; static const char * const libbpf_type_to_btf_name[] = { [LIBBPF_MAP_DATA] = DATA_SEC, [LIBBPF_MAP_BSS] = BSS_SEC, [LIBBPF_MAP_RODATA] = RODATA_SEC, + [LIBBPF_MAP_EXTERN] = EXTERN_SEC, }; struct bpf_map { @@ -231,6 +240,28 @@ struct bpf_map { bool reused; }; +enum extern_type { + EXT_UNKNOWN, + EXT_CHAR, + EXT_BOOL, + EXT_INT, + EXT_TRISTATE, + EXT_CHAR_ARR, +}; + +struct extern_desc { + const char *name; + int sym_idx; + int btf_id; + enum extern_type type; + int sz; + int align; + int data_off; + bool is_signed; + bool is_weak; + bool is_set; +}; + static LIST_HEAD(bpf_objects_list); struct bpf_object { @@ -244,6 +275,11 @@ struct bpf_object { size_t nr_maps; size_t maps_cap; + char *kconfig_path; + struct extern_desc *externs; + int nr_extern; + int extern_map_idx; + bool loaded; bool has_pseudo_calls; bool relaxed_core_relocs; @@ -271,6 +307,7 @@ struct bpf_object { int maps_shndx; int btf_maps_shndx; int text_shndx; + int symbols_shndx; int data_shndx; int rodata_shndx; int bss_shndx; @@ -542,6 +579,7 @@ static struct bpf_object *bpf_object__new(const char *path, obj->efile.data_shndx = -1; obj->efile.rodata_shndx = -1; obj->efile.bss_shndx = -1; + obj->extern_map_idx = -1; obj->kern_version = get_kernel_version(); obj->loaded = false; @@ -866,7 +904,8 @@ bpf_object__init_internal_map(struct bpf_object *obj, enum libbpf_map_type type, def->key_size = sizeof(int); def->value_size = data_sz; def->max_entries = 1; - def->map_flags = type == LIBBPF_MAP_RODATA ? BPF_F_RDONLY_PROG : 0; + def->map_flags = type == LIBBPF_MAP_RODATA || type == LIBBPF_MAP_EXTERN + ? BPF_F_RDONLY_PROG : 0; def->map_flags |= BPF_F_MMAPABLE; pr_debug("map '%s' (global data): at sec_idx %d, offset %zu, flags %x.\n", @@ -883,7 +922,7 @@ bpf_object__init_internal_map(struct bpf_object *obj, enum libbpf_map_type type, return err; } - if (type != LIBBPF_MAP_BSS) + if (data) memcpy(map->mmaped, data, data_sz); pr_debug("map %td is \"%s\"\n", map - obj->maps, map->name); @@ -924,6 +963,271 @@ static int bpf_object__init_global_data_maps(struct bpf_object *obj) return 0; } + +static struct extern_desc *find_extern_by_name(const struct bpf_object *obj, + const void *name) +{ + int i; + + for (i = 0; i < obj->nr_extern; i++) { + if (strcmp(obj->externs[i].name, name) == 0) + return &obj->externs[i]; + } + return NULL; +} + +static int set_ext_value_tri(struct extern_desc *ext, void *ext_val, + char value) +{ + switch (ext->type) { + case EXT_BOOL: + if (value == 'm') { + pr_warn("extern %s=%c should be tristate or char\n", + ext->name, value); + return -EINVAL; + } + *(bool *)ext_val = value == 'y' ? true : false; + break; + case EXT_TRISTATE: + if (value == 'y') + *(enum libbpf_tristate *)ext_val = TRI_YES; + else if (value == 'm') + *(enum libbpf_tristate *)ext_val = TRI_MODULE; + else /* value == 'n' */ + *(enum libbpf_tristate *)ext_val = TRI_NO; + break; + case EXT_CHAR: + *(char *)ext_val = value; + break; + case EXT_UNKNOWN: + case EXT_INT: + case EXT_CHAR_ARR: + default: + pr_warn("extern %s=%c should be bool, tristate, or char\n", + ext->name, value); + return -EINVAL; + } + ext->is_set = true; + return 0; +} + +static int set_ext_value_str(struct extern_desc *ext, char *ext_val, + const char *value) +{ + size_t len; + + if (ext->type != EXT_CHAR_ARR) { + pr_warn("extern %s=%s should char array\n", ext->name, value); + return -EINVAL; + } + + len = strlen(value); + if (value[len - 1] != '"') { + pr_warn("extern '%s': invalid string config '%s'\n", + ext->name, value); + return -EINVAL; + } + + /* strip quotes */ + len -= 2; + if (len >= ext->sz) { + pr_warn("extern '%s': long string config %s of (%zu bytes) truncated to %d bytes\n", + ext->name, value, len, ext->sz - 1); + len = ext->sz - 1; + } + memcpy(ext_val, value + 1, len); + ext_val[len] = '\0'; + ext->is_set = true; + return 0; +} + +static int parse_u64(const char *value, __u64 *res) +{ + char *value_end; + int err; + + errno = 0; + *res = strtoull(value, &value_end, 0); + if (errno) { + err = -errno; + pr_warn("failed to parse '%s' as integer: %d\n", value, err); + return err; + } + if (*value_end) { + pr_warn("failed to parse '%s' as integer completely\n", value); + return -EINVAL; + } + return 0; +} + +static bool is_ext_value_in_range(const struct extern_desc *ext, __u64 v) +{ + int bit_sz = ext->sz * 8; + + if (ext->sz == 8) + return true; + + /* Validate that value stored in u64 fits in integer of `ext->sz` + * bytes size without any loss of information. If the target integer + * is signed, we rely on the following limits of integer type of + * Y bits and subsequent transformation: + * + * -2^(Y-1) <= X <= 2^(Y-1) - 1 + * 0 <= X + 2^(Y-1) <= 2^Y - 1 + * 0 <= X + 2^(Y-1) < 2^Y + * + * For unsigned target integer, check that all the (64 - Y) bits are + * zero. + */ + if (ext->is_signed) + return v + (1ULL << (bit_sz - 1)) < (1ULL << bit_sz); + else + return (v >> bit_sz) == 0; +} + +static int set_ext_value_num(struct extern_desc *ext, void *ext_val, + __u64 value) +{ + if (ext->type != EXT_INT && ext->type != EXT_CHAR) { + pr_warn("extern %s=%llu should be integer\n", + ext->name, value); + return -EINVAL; + } + if (!is_ext_value_in_range(ext, value)) { + pr_warn("extern %s=%llu value doesn't fit in %d bytes\n", + ext->name, value, ext->sz); + return -ERANGE; + } + switch (ext->sz) { + case 1: *(__u8 *)ext_val = value; break; + case 2: *(__u16 *)ext_val = value; break; + case 4: *(__u32 *)ext_val = value; break; + case 8: *(__u64 *)ext_val = value; break; + default: + return -EINVAL; + } + ext->is_set = true; + return 0; +} + +static int bpf_object__read_kernel_config(struct bpf_object *obj, + const char *config_path, + void *data) +{ + char buf[PATH_MAX], *sep, *value; + struct extern_desc *ext; + int len, err = 0; + void *ext_val; + __u64 num; + gzFile file; + + if (config_path) { + file = gzopen(config_path, "r"); + } else { + struct utsname uts; + + uname(&uts); + len = snprintf(buf, PATH_MAX, "/boot/config-%s", uts.release); + if (len < 0) + return -EINVAL; + else if (len >= PATH_MAX) + return -ENAMETOOLONG; + /* gzopen also accepts uncompressed files. */ + file = gzopen(buf, "r"); + if (!file) + file = gzopen("/proc/config.gz", "r"); + } + if (!file) { + pr_warn("failed to read kernel config at '%s'\n", config_path); + return -ENOENT; + } + + while (gzgets(file, buf, sizeof(buf))) { + if (strncmp(buf, "CONFIG_", 7)) + continue; + + sep = strchr(buf, '='); + if (!sep) { + err = -EINVAL; + pr_warn("failed to parse '%s': no separator\n", buf); + goto out; + } + /* Trim ending '\n' */ + len = strlen(buf); + if (buf[len - 1] == '\n') + buf[len - 1] = '\0'; + /* Split on '=' and ensure that a value is present. */ + *sep = '\0'; + if (!sep[1]) { + err = -EINVAL; + *sep = '='; + pr_warn("failed to parse '%s': no value\n", buf); + goto out; + } + + ext = find_extern_by_name(obj, buf); + if (!ext) + continue; + if (ext->is_set) { + err = -EINVAL; + pr_warn("re-defining extern '%s' not allowed\n", buf); + goto out; + } + + ext_val = data + ext->data_off; + value = sep + 1; + + switch (*value) { + case 'y': case 'n': case 'm': + err = set_ext_value_tri(ext, ext_val, *value); + break; + case '"': + err = set_ext_value_str(ext, ext_val, value); + break; + default: + /* assume integer */ + err = parse_u64(value, &num); + if (err) { + pr_warn("extern %s=%s should be integer\n", + ext->name, value); + goto out; + } + err = set_ext_value_num(ext, ext_val, num); + break; + } + if (err) + goto out; + pr_debug("extern %s=%s\n", ext->name, value); + } + +out: + gzclose(file); + return err; +} + +static int bpf_object__init_extern_map(struct bpf_object *obj) +{ + struct extern_desc *last_ext; + size_t map_sz; + int err; + + if (obj->nr_extern == 0) + return 0; + + last_ext = &obj->externs[obj->nr_extern - 1]; + map_sz = last_ext->data_off + last_ext->sz; + + err = bpf_object__init_internal_map(obj, LIBBPF_MAP_EXTERN, + obj->efile.symbols_shndx, + NULL, map_sz); + if (err) + return err; + + obj->extern_map_idx = obj->nr_maps - 1; + + return 0; +} + static int bpf_object__init_user_maps(struct bpf_object *obj, bool strict) { Elf_Data *symbols = obj->efile.symbols; @@ -1401,19 +1705,17 @@ static int bpf_object__init_user_btf_maps(struct bpf_object *obj, bool strict, static int bpf_object__init_maps(struct bpf_object *obj, const struct bpf_object_open_opts *opts) { - const char *pin_root_path = OPTS_GET(opts, pin_root_path, NULL); - bool strict = !OPTS_GET(opts, relaxed_maps, false); + const char *pin_root_path; + bool strict; int err; - err = bpf_object__init_user_maps(obj, strict); - if (err) - return err; + strict = !OPTS_GET(opts, relaxed_maps, false); + pin_root_path = OPTS_GET(opts, pin_root_path, NULL); - err = bpf_object__init_user_btf_maps(obj, strict, pin_root_path); - if (err) - return err; - - err = bpf_object__init_global_data_maps(obj); + err = bpf_object__init_user_maps(obj, strict); + err = err ?: bpf_object__init_user_btf_maps(obj, strict, pin_root_path); + err = err ?: bpf_object__init_global_data_maps(obj); + err = err ?: bpf_object__init_extern_map(obj); if (err) return err; @@ -1532,11 +1834,6 @@ static int bpf_object__init_btf(struct bpf_object *obj, BTF_ELF_SEC, err); goto out; } - err = btf__finalize_data(obj, obj->btf); - if (err) { - pr_warn("Error finalizing %s: %d.\n", BTF_ELF_SEC, err); - goto out; - } } if (btf_ext_data) { if (!obj->btf) { @@ -1570,6 +1867,30 @@ out: return 0; } +static int bpf_object__finalize_btf(struct bpf_object *obj) +{ + int err; + + if (!obj->btf) + return 0; + + err = btf__finalize_data(obj, obj->btf); + if (!err) + return 0; + + pr_warn("Error finalizing %s: %d.\n", BTF_ELF_SEC, err); + btf__free(obj->btf); + obj->btf = NULL; + btf_ext__free(obj->btf_ext); + obj->btf_ext = NULL; + + if (bpf_object__is_btf_mandatory(obj)) { + pr_warn("BTF is required, but is missing or corrupted.\n"); + return -ENOENT; + } + return 0; +} + static int bpf_object__sanitize_and_load_btf(struct bpf_object *obj) { int err = 0; @@ -1670,6 +1991,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj) return -LIBBPF_ERRNO__FORMAT; } obj->efile.symbols = data; + obj->efile.symbols_shndx = idx; obj->efile.strtabidx = sh.sh_link; } else if (sh.sh_type == SHT_PROGBITS && data->d_size > 0) { if (sh.sh_flags & SHF_EXECINSTR) { @@ -1737,6 +2059,216 @@ static int bpf_object__elf_collect(struct bpf_object *obj) return bpf_object__init_btf(obj, btf_data, btf_ext_data); } +static bool sym_is_extern(const GElf_Sym *sym) +{ + int bind = GELF_ST_BIND(sym->st_info); + /* externs are symbols w/ type=NOTYPE, bind=GLOBAL|WEAK, section=UND */ + return sym->st_shndx == SHN_UNDEF && + (bind == STB_GLOBAL || bind == STB_WEAK) && + GELF_ST_TYPE(sym->st_info) == STT_NOTYPE; +} + +static int find_extern_btf_id(const struct btf *btf, const char *ext_name) +{ + const struct btf_type *t; + const char *var_name; + int i, n; + + if (!btf) + return -ESRCH; + + n = btf__get_nr_types(btf); + for (i = 1; i <= n; i++) { + t = btf__type_by_id(btf, i); + + if (!btf_is_var(t)) + continue; + + var_name = btf__name_by_offset(btf, t->name_off); + if (strcmp(var_name, ext_name)) + continue; + + if (btf_var(t)->linkage != BTF_VAR_GLOBAL_EXTERN) + return -EINVAL; + + return i; + } + + return -ENOENT; +} + +static enum extern_type find_extern_type(const struct btf *btf, int id, + bool *is_signed) +{ + const struct btf_type *t; + const char *name; + + t = skip_mods_and_typedefs(btf, id, NULL); + name = btf__name_by_offset(btf, t->name_off); + + if (is_signed) + *is_signed = false; + switch (btf_kind(t)) { + case BTF_KIND_INT: { + int enc = btf_int_encoding(t); + + if (enc & BTF_INT_BOOL) + return t->size == 1 ? EXT_BOOL : EXT_UNKNOWN; + if (is_signed) + *is_signed = enc & BTF_INT_SIGNED; + if (t->size == 1) + return EXT_CHAR; + if (t->size < 1 || t->size > 8 || (t->size & (t->size - 1))) + return EXT_UNKNOWN; + return EXT_INT; + } + case BTF_KIND_ENUM: + if (t->size != 4) + return EXT_UNKNOWN; + if (strcmp(name, "libbpf_tristate")) + return EXT_UNKNOWN; + return EXT_TRISTATE; + case BTF_KIND_ARRAY: + if (btf_array(t)->nelems == 0) + return EXT_UNKNOWN; + if (find_extern_type(btf, btf_array(t)->type, NULL) != EXT_CHAR) + return EXT_UNKNOWN; + return EXT_CHAR_ARR; + default: + return EXT_UNKNOWN; + } +} + +static int cmp_externs(const void *_a, const void *_b) +{ + const struct extern_desc *a = _a; + const struct extern_desc *b = _b; + + /* descending order by alignment requirements */ + if (a->align != b->align) + return a->align > b->align ? -1 : 1; + /* ascending order by size, within same alignment class */ + if (a->sz != b->sz) + return a->sz < b->sz ? -1 : 1; + /* resolve ties by name */ + return strcmp(a->name, b->name); +} + +static int bpf_object__collect_externs(struct bpf_object *obj) +{ + const struct btf_type *t; + struct extern_desc *ext; + int i, n, off, btf_id; + struct btf_type *sec; + const char *ext_name; + Elf_Scn *scn; + GElf_Shdr sh; + + if (!obj->efile.symbols) + return 0; + + scn = elf_getscn(obj->efile.elf, obj->efile.symbols_shndx); + if (!scn) + return -LIBBPF_ERRNO__FORMAT; + if (gelf_getshdr(scn, &sh) != &sh) + return -LIBBPF_ERRNO__FORMAT; + n = sh.sh_size / sh.sh_entsize; + + pr_debug("looking for externs among %d symbols...\n", n); + for (i = 0; i < n; i++) { + GElf_Sym sym; + + if (!gelf_getsym(obj->efile.symbols, i, &sym)) + return -LIBBPF_ERRNO__FORMAT; + if (!sym_is_extern(&sym)) + continue; + ext_name = elf_strptr(obj->efile.elf, obj->efile.strtabidx, + sym.st_name); + if (!ext_name || !ext_name[0]) + continue; + + ext = obj->externs; + ext = reallocarray(ext, obj->nr_extern + 1, sizeof(*ext)); + if (!ext) + return -ENOMEM; + obj->externs = ext; + ext = &ext[obj->nr_extern]; + memset(ext, 0, sizeof(*ext)); + obj->nr_extern++; + + ext->btf_id = find_extern_btf_id(obj->btf, ext_name); + if (ext->btf_id <= 0) { + pr_warn("failed to find BTF for extern '%s': %d\n", + ext_name, ext->btf_id); + return ext->btf_id; + } + t = btf__type_by_id(obj->btf, ext->btf_id); + ext->name = btf__name_by_offset(obj->btf, t->name_off); + ext->sym_idx = i; + ext->is_weak = GELF_ST_BIND(sym.st_info) == STB_WEAK; + ext->sz = btf__resolve_size(obj->btf, t->type); + if (ext->sz <= 0) { + pr_warn("failed to resolve size of extern '%s': %d\n", + ext_name, ext->sz); + return ext->sz; + } + ext->align = btf__align_of(obj->btf, t->type); + if (ext->align <= 0) { + pr_warn("failed to determine alignment of extern '%s': %d\n", + ext_name, ext->align); + return -EINVAL; + } + ext->type = find_extern_type(obj->btf, t->type, + &ext->is_signed); + if (ext->type == EXT_UNKNOWN) { + pr_warn("extern '%s' type is unsupported\n", ext_name); + return -ENOTSUP; + } + } + pr_debug("collected %d externs total\n", obj->nr_extern); + + if (!obj->nr_extern) + return 0; + + /* sort externs by (alignment, size, name) and calculate their offsets + * within a map */ + qsort(obj->externs, obj->nr_extern, sizeof(*ext), cmp_externs); + off = 0; + for (i = 0; i < obj->nr_extern; i++) { + ext = &obj->externs[i]; + ext->data_off = roundup(off, ext->align); + off = ext->data_off + ext->sz; + pr_debug("extern #%d: symbol %d, off %u, name %s\n", + i, ext->sym_idx, ext->data_off, ext->name); + } + + btf_id = btf__find_by_name(obj->btf, EXTERN_SEC); + if (btf_id <= 0) { + pr_warn("no BTF info found for '%s' datasec\n", EXTERN_SEC); + return -ESRCH; + } + + sec = (struct btf_type *)btf__type_by_id(obj->btf, btf_id); + sec->size = off; + n = btf_vlen(sec); + for (i = 0; i < n; i++) { + struct btf_var_secinfo *vs = btf_var_secinfos(sec) + i; + + t = btf__type_by_id(obj->btf, vs->type); + ext_name = btf__name_by_offset(obj->btf, t->name_off); + ext = find_extern_by_name(obj, ext_name); + if (!ext) { + pr_warn("failed to find extern definition for BTF var '%s'\n", + ext_name); + return -ESRCH; + } + vs->offset = ext->data_off; + btf_var(t)->linkage = BTF_VAR_GLOBAL_ALLOCATED; + } + + return 0; +} + static struct bpf_program * bpf_object__find_prog_by_idx(struct bpf_object *obj, int idx) { @@ -1801,6 +2333,8 @@ bpf_object__section_to_libbpf_map_type(const struct bpf_object *obj, int shndx) return LIBBPF_MAP_BSS; else if (shndx == obj->efile.rodata_shndx) return LIBBPF_MAP_RODATA; + else if (shndx == obj->efile.symbols_shndx) + return LIBBPF_MAP_EXTERN; else return LIBBPF_MAP_UNSPEC; } @@ -1845,6 +2379,30 @@ static int bpf_program__record_reloc(struct bpf_program *prog, insn_idx, insn->code); return -LIBBPF_ERRNO__RELOC; } + + if (sym_is_extern(sym)) { + int sym_idx = GELF_R_SYM(rel->r_info); + int i, n = obj->nr_extern; + struct extern_desc *ext; + + for (i = 0; i < n; i++) { + ext = &obj->externs[i]; + if (ext->sym_idx == sym_idx) + break; + } + if (i >= n) { + pr_warn("extern relo failed to find extern for sym %d\n", + sym_idx); + return -LIBBPF_ERRNO__RELOC; + } + pr_debug("found extern #%d '%s' (sym %d, off %u) for insn %u\n", + i, ext->name, ext->sym_idx, ext->data_off, insn_idx); + reloc_desc->type = RELO_EXTERN; + reloc_desc->insn_idx = insn_idx; + reloc_desc->sym_off = ext->data_off; + return 0; + } + if (!shdr_idx || shdr_idx >= SHN_LORESERVE) { pr_warn("invalid relo for \'%s\' in special section 0x%x; forgot to initialize global var?..\n", name, shdr_idx); @@ -2306,11 +2864,12 @@ bpf_object__reuse_map(struct bpf_map *map) static int bpf_object__populate_internal_map(struct bpf_object *obj, struct bpf_map *map) { + enum libbpf_map_type map_type = map->libbpf_type; char *cp, errmsg[STRERR_BUFSIZE]; int err, zero = 0; - /* Nothing to do here since kernel already zero-initializes .bss map. */ - if (map->libbpf_type == LIBBPF_MAP_BSS) + /* kernel already zero-initializes .bss map. */ + if (map_type == LIBBPF_MAP_BSS) return 0; err = bpf_map_update_elem(map->fd, &zero, map->mmaped, 0); @@ -2322,8 +2881,8 @@ bpf_object__populate_internal_map(struct bpf_object *obj, struct bpf_map *map) return err; } - /* Freeze .rodata map as read-only from syscall side. */ - if (map->libbpf_type == LIBBPF_MAP_RODATA) { + /* Freeze .rodata and .extern map as read-only from syscall side. */ + if (map_type == LIBBPF_MAP_RODATA || map_type == LIBBPF_MAP_EXTERN) { err = bpf_map_freeze(map->fd); if (err) { err = -errno; @@ -3572,9 +4131,6 @@ bpf_program__reloc_text(struct bpf_program *prog, struct bpf_object *obj, size_t new_cnt; int err; - if (relo->type != RELO_CALL) - return -LIBBPF_ERRNO__RELOC; - if (prog->idx == obj->efile.text_shndx) { pr_warn("relo in .text insn %d into off %d (insn #%d)\n", relo->insn_idx, relo->sym_off, relo->sym_off / 8); @@ -3636,27 +4192,37 @@ bpf_program__relocate(struct bpf_program *prog, struct bpf_object *obj) for (i = 0; i < prog->nr_reloc; i++) { struct reloc_desc *relo = &prog->reloc_desc[i]; + struct bpf_insn *insn = &prog->insns[relo->insn_idx]; - if (relo->type == RELO_LD64 || relo->type == RELO_DATA) { - struct bpf_insn *insn = &prog->insns[relo->insn_idx]; - - if (relo->insn_idx + 1 >= (int)prog->insns_cnt) { - pr_warn("relocation out of range: '%s'\n", - prog->section_name); - return -LIBBPF_ERRNO__RELOC; - } + if (relo->insn_idx + 1 >= (int)prog->insns_cnt) { + pr_warn("relocation out of range: '%s'\n", + prog->section_name); + return -LIBBPF_ERRNO__RELOC; + } - if (relo->type != RELO_DATA) { - insn[0].src_reg = BPF_PSEUDO_MAP_FD; - } else { - insn[0].src_reg = BPF_PSEUDO_MAP_VALUE; - insn[1].imm = insn[0].imm + relo->sym_off; - } + switch (relo->type) { + case RELO_LD64: + insn[0].src_reg = BPF_PSEUDO_MAP_FD; + insn[0].imm = obj->maps[relo->map_idx].fd; + break; + case RELO_DATA: + insn[0].src_reg = BPF_PSEUDO_MAP_VALUE; + insn[1].imm = insn[0].imm + relo->sym_off; insn[0].imm = obj->maps[relo->map_idx].fd; - } else if (relo->type == RELO_CALL) { + break; + case RELO_EXTERN: + insn[0].src_reg = BPF_PSEUDO_MAP_VALUE; + insn[0].imm = obj->maps[obj->extern_map_idx].fd; + insn[1].imm = relo->sym_off; + break; + case RELO_CALL: err = bpf_program__reloc_text(prog, obj, relo); if (err) return err; + break; + default: + pr_warn("relo #%d: bad relo type %d\n", i, relo->type); + return -EINVAL; } } @@ -3936,11 +4502,10 @@ static struct bpf_object * __bpf_object__open(const char *path, const void *obj_buf, size_t obj_buf_sz, const struct bpf_object_open_opts *opts) { + const char *obj_name, *kconfig_path; struct bpf_program *prog; struct bpf_object *obj; - const char *obj_name; char tmp_name[64]; - __u32 attach_prog_fd; int err; if (elf_version(EV_CURRENT) == EV_NONE) { @@ -3969,11 +4534,18 @@ __bpf_object__open(const char *path, const void *obj_buf, size_t obj_buf_sz, return obj; obj->relaxed_core_relocs = OPTS_GET(opts, relaxed_core_relocs, false); - attach_prog_fd = OPTS_GET(opts, attach_prog_fd, 0); + kconfig_path = OPTS_GET(opts, kconfig_path, NULL); + if (kconfig_path) { + obj->kconfig_path = strdup(kconfig_path); + if (!obj->kconfig_path) + return ERR_PTR(-ENOMEM); + } err = bpf_object__elf_init(obj); err = err ? : bpf_object__check_endianness(obj); err = err ? : bpf_object__elf_collect(obj); + err = err ? : bpf_object__collect_externs(obj); + err = err ? : bpf_object__finalize_btf(obj); err = err ? : bpf_object__init_maps(obj, opts); err = err ? : bpf_object__init_prog_names(obj); err = err ? : bpf_object__collect_reloc(obj); @@ -3996,7 +4568,7 @@ __bpf_object__open(const char *path, const void *obj_buf, size_t obj_buf_sz, bpf_program__set_type(prog, prog_type); bpf_program__set_expected_attach_type(prog, attach_type); if (prog_type == BPF_PROG_TYPE_TRACING) - prog->attach_prog_fd = attach_prog_fd; + prog->attach_prog_fd = OPTS_GET(opts, attach_prog_fd, 0); } return obj; @@ -4107,6 +4679,61 @@ static int bpf_object__sanitize_maps(struct bpf_object *obj) return 0; } +static int bpf_object__resolve_externs(struct bpf_object *obj, + const char *config_path) +{ + bool need_config = false; + struct extern_desc *ext; + int err, i; + void *data; + + if (obj->nr_extern == 0) + return 0; + + data = obj->maps[obj->extern_map_idx].mmaped; + + for (i = 0; i < obj->nr_extern; i++) { + ext = &obj->externs[i]; + + if (strcmp(ext->name, "LINUX_KERNEL_VERSION") == 0) { + void *ext_val = data + ext->data_off; + __u32 kver = get_kernel_version(); + + if (!kver) { + pr_warn("failed to get kernel version\n"); + return -EINVAL; + } + err = set_ext_value_num(ext, ext_val, kver); + if (err) + return err; + pr_debug("extern %s=0x%x\n", ext->name, kver); + } else if (strncmp(ext->name, "CONFIG_", 7) == 0) { + need_config = true; + } else { + pr_warn("unrecognized extern '%s'\n", ext->name); + return -EINVAL; + } + } + if (need_config) { + err = bpf_object__read_kernel_config(obj, config_path, data); + if (err) + return -EINVAL; + } + for (i = 0; i < obj->nr_extern; i++) { + ext = &obj->externs[i]; + + if (!ext->is_set && !ext->is_weak) { + pr_warn("extern %s (strong) not resolved\n", ext->name); + return -ESRCH; + } else if (!ext->is_set) { + pr_debug("extern %s (weak) not resolved, defaulting to zero\n", + ext->name); + } + } + + return 0; +} + int bpf_object__load_xattr(struct bpf_object_load_attr *attr) { struct bpf_object *obj; @@ -4126,6 +4753,7 @@ int bpf_object__load_xattr(struct bpf_object_load_attr *attr) obj->loaded = true; err = bpf_object__probe_caps(obj); + err = err ? : bpf_object__resolve_externs(obj, obj->kconfig_path); err = err ? : bpf_object__sanitize_and_load_btf(obj); err = err ? : bpf_object__sanitize_maps(obj); err = err ? : bpf_object__create_maps(obj); @@ -4719,6 +5347,10 @@ void bpf_object__close(struct bpf_object *obj) zfree(&map->pin_path); } + zfree(&obj->kconfig_path); + zfree(&obj->externs); + obj->nr_extern = 0; + zfree(&obj->maps); obj->nr_maps = 0; diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 623191e71415..6340823871e2 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -85,8 +85,12 @@ struct bpf_object_open_opts { */ const char *pin_root_path; __u32 attach_prog_fd; + /* kernel config file path override (for CONFIG_ externs); can point + * to either uncompressed text file or .gz file + */ + const char *kconfig_path; }; -#define bpf_object_open_opts__last_field attach_prog_fd +#define bpf_object_open_opts__last_field kconfig_path LIBBPF_API struct bpf_object *bpf_object__open(const char *path); LIBBPF_API struct bpf_object * @@ -669,6 +673,12 @@ LIBBPF_API int bpf_object__attach_skeleton(struct bpf_object_skeleton *s); LIBBPF_API void bpf_object__detach_skeleton(struct bpf_object_skeleton *s); LIBBPF_API void bpf_object__destroy_skeleton(struct bpf_object_skeleton *s); +enum libbpf_tristate { + TRI_NO = 0, + TRI_YES = 1, + TRI_MODULE = 2, +}; + #ifdef __cplusplus } /* extern "C" */ #endif diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index f70c8e735120..ba90621617a8 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -24,7 +24,7 @@ CFLAGS += -g -Wall -O2 $(GENFLAGS) -I$(APIDIR) -I$(LIBDIR) -I$(BPFDIR) \ -I$(GENDIR) -I$(TOOLSINCDIR) -I$(CURDIR) \ -Dbpf_prog_load=bpf_prog_test_load \ -Dbpf_load_program=bpf_test_load_program -LDLIBS += -lcap -lelf -lrt -lpthread +LDLIBS += -lcap -lelf -lz -lrt -lpthread # Order correspond to 'make run_tests' order TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test_progs \ -- cgit v1.2.3 From e312b9e706ed6d94f6cc9088fcd9fbd81de4525c Mon Sep 17 00:00:00 2001 From: Björn Töpel Date: Thu, 19 Dec 2019 07:10:02 +0100 Subject: xsk: Make xskmap flush_list common for all map instances MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The xskmap flush list is used to track entries that need to flushed from via the xdp_do_flush_map() function. This list used to be per-map, but there is really no reason for that. Instead make the flush list global for all xskmaps, which simplifies __xsk_map_flush() and xsk_map_alloc(). Signed-off-by: Björn Töpel Signed-off-by: Alexei Starovoitov Acked-by: Toke Høiland-Jørgensen Link: https://lore.kernel.org/bpf/20191219061006.21980-5-bjorn.topel@gmail.com --- include/net/xdp_sock.h | 11 ++++------- kernel/bpf/xskmap.c | 18 +++--------------- net/core/filter.c | 9 ++++----- net/xdp/xsk.c | 17 +++++++++-------- 4 files changed, 20 insertions(+), 35 deletions(-) (limited to 'include') diff --git a/include/net/xdp_sock.h b/include/net/xdp_sock.h index e3780e4b74e1..48594740d67c 100644 --- a/include/net/xdp_sock.h +++ b/include/net/xdp_sock.h @@ -72,7 +72,6 @@ struct xdp_umem { struct xsk_map { struct bpf_map map; - struct list_head __percpu *flush_list; spinlock_t lock; /* Synchronize map updates */ struct xdp_sock *xsk_map[]; }; @@ -139,9 +138,8 @@ void xsk_map_try_sock_delete(struct xsk_map *map, struct xdp_sock *xs, struct xdp_sock **map_entry); int xsk_map_inc(struct xsk_map *map); void xsk_map_put(struct xsk_map *map); -int __xsk_map_redirect(struct bpf_map *map, struct xdp_buff *xdp, - struct xdp_sock *xs); -void __xsk_map_flush(struct bpf_map *map); +int __xsk_map_redirect(struct xdp_sock *xs, struct xdp_buff *xdp); +void __xsk_map_flush(void); static inline struct xdp_sock *__xsk_map_lookup_elem(struct bpf_map *map, u32 key) @@ -369,13 +367,12 @@ static inline u64 xsk_umem_adjust_offset(struct xdp_umem *umem, u64 handle, return 0; } -static inline int __xsk_map_redirect(struct bpf_map *map, struct xdp_buff *xdp, - struct xdp_sock *xs) +static inline int __xsk_map_redirect(struct xdp_sock *xs, struct xdp_buff *xdp) { return -EOPNOTSUPP; } -static inline void __xsk_map_flush(struct bpf_map *map) +static inline void __xsk_map_flush(void) { } diff --git a/kernel/bpf/xskmap.c b/kernel/bpf/xskmap.c index 90c4fce1c981..2cc5c8f4c800 100644 --- a/kernel/bpf/xskmap.c +++ b/kernel/bpf/xskmap.c @@ -72,9 +72,9 @@ static void xsk_map_sock_delete(struct xdp_sock *xs, static struct bpf_map *xsk_map_alloc(union bpf_attr *attr) { struct bpf_map_memory mem; - int cpu, err, numa_node; + int err, numa_node; struct xsk_map *m; - u64 cost, size; + u64 size; if (!capable(CAP_NET_ADMIN)) return ERR_PTR(-EPERM); @@ -86,9 +86,8 @@ static struct bpf_map *xsk_map_alloc(union bpf_attr *attr) numa_node = bpf_map_attr_numa_node(attr); size = struct_size(m, xsk_map, attr->max_entries); - cost = size + array_size(sizeof(*m->flush_list), num_possible_cpus()); - err = bpf_map_charge_init(&mem, cost); + err = bpf_map_charge_init(&mem, size); if (err < 0) return ERR_PTR(err); @@ -102,16 +101,6 @@ static struct bpf_map *xsk_map_alloc(union bpf_attr *attr) bpf_map_charge_move(&m->map.memory, &mem); spin_lock_init(&m->lock); - m->flush_list = alloc_percpu(struct list_head); - if (!m->flush_list) { - bpf_map_charge_finish(&m->map.memory); - bpf_map_area_free(m); - return ERR_PTR(-ENOMEM); - } - - for_each_possible_cpu(cpu) - INIT_LIST_HEAD(per_cpu_ptr(m->flush_list, cpu)); - return &m->map; } @@ -121,7 +110,6 @@ static void xsk_map_free(struct bpf_map *map) bpf_clear_redirect_map(map); synchronize_net(); - free_percpu(m->flush_list); bpf_map_area_free(m); } diff --git a/net/core/filter.c b/net/core/filter.c index a411f7835dee..c51678c473c5 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -3511,8 +3511,7 @@ err: static int __bpf_tx_xdp_map(struct net_device *dev_rx, void *fwd, struct bpf_map *map, - struct xdp_buff *xdp, - u32 index) + struct xdp_buff *xdp) { int err; @@ -3537,7 +3536,7 @@ static int __bpf_tx_xdp_map(struct net_device *dev_rx, void *fwd, case BPF_MAP_TYPE_XSKMAP: { struct xdp_sock *xs = fwd; - err = __xsk_map_redirect(map, xdp, xs); + err = __xsk_map_redirect(xs, xdp); return err; } default: @@ -3562,7 +3561,7 @@ void xdp_do_flush_map(void) __cpu_map_flush(map); break; case BPF_MAP_TYPE_XSKMAP: - __xsk_map_flush(map); + __xsk_map_flush(); break; default: break; @@ -3619,7 +3618,7 @@ static int xdp_do_redirect_map(struct net_device *dev, struct xdp_buff *xdp, if (ri->map_to_flush && unlikely(ri->map_to_flush != map)) xdp_do_flush_map(); - err = __bpf_tx_xdp_map(dev, fwd, map, xdp, index); + err = __bpf_tx_xdp_map(dev, fwd, map, xdp); if (unlikely(err)) goto err; diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c index 956793893c9d..e45c27f5cfca 100644 --- a/net/xdp/xsk.c +++ b/net/xdp/xsk.c @@ -31,6 +31,8 @@ #define TX_BATCH_SIZE 16 +static DEFINE_PER_CPU(struct list_head, xskmap_flush_list); + bool xsk_is_setup_for_bpf_map(struct xdp_sock *xs) { return READ_ONCE(xs->rx) && READ_ONCE(xs->umem) && @@ -264,11 +266,9 @@ out_unlock: return err; } -int __xsk_map_redirect(struct bpf_map *map, struct xdp_buff *xdp, - struct xdp_sock *xs) +int __xsk_map_redirect(struct xdp_sock *xs, struct xdp_buff *xdp) { - struct xsk_map *m = container_of(map, struct xsk_map, map); - struct list_head *flush_list = this_cpu_ptr(m->flush_list); + struct list_head *flush_list = this_cpu_ptr(&xskmap_flush_list); int err; err = xsk_rcv(xs, xdp); @@ -281,10 +281,9 @@ int __xsk_map_redirect(struct bpf_map *map, struct xdp_buff *xdp, return 0; } -void __xsk_map_flush(struct bpf_map *map) +void __xsk_map_flush(void) { - struct xsk_map *m = container_of(map, struct xsk_map, map); - struct list_head *flush_list = this_cpu_ptr(m->flush_list); + struct list_head *flush_list = this_cpu_ptr(&xskmap_flush_list); struct xdp_sock *xs, *tmp; list_for_each_entry_safe(xs, tmp, flush_list, flush_node) { @@ -1177,7 +1176,7 @@ static struct pernet_operations xsk_net_ops = { static int __init xsk_init(void) { - int err; + int err, cpu; err = proto_register(&xsk_proto, 0 /* no slab */); if (err) @@ -1195,6 +1194,8 @@ static int __init xsk_init(void) if (err) goto out_pernet; + for_each_possible_cpu(cpu) + INIT_LIST_HEAD(&per_cpu(xskmap_flush_list, cpu)); return 0; out_pernet: -- cgit v1.2.3 From 96360004b8628541f5d05a845ea213267db0b1a2 Mon Sep 17 00:00:00 2001 From: Björn Töpel Date: Thu, 19 Dec 2019 07:10:03 +0100 Subject: xdp: Make devmap flush_list common for all map instances MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The devmap flush list is used to track entries that need to flushed from via the xdp_do_flush_map() function. This list used to be per-map, but there is really no reason for that. Instead make the flush list global for all devmaps, which simplifies __dev_map_flush() and dev_map_init_map(). Signed-off-by: Björn Töpel Signed-off-by: Alexei Starovoitov Acked-by: Toke Høiland-Jørgensen Link: https://lore.kernel.org/bpf/20191219061006.21980-6-bjorn.topel@gmail.com --- include/linux/bpf.h | 4 ++-- kernel/bpf/devmap.c | 35 +++++++++++++---------------------- net/core/filter.c | 2 +- 3 files changed, 16 insertions(+), 25 deletions(-) (limited to 'include') diff --git a/include/linux/bpf.h b/include/linux/bpf.h index d467983e61bb..31191804ca09 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -959,7 +959,7 @@ struct sk_buff; struct bpf_dtab_netdev *__dev_map_lookup_elem(struct bpf_map *map, u32 key); struct bpf_dtab_netdev *__dev_map_hash_lookup_elem(struct bpf_map *map, u32 key); -void __dev_map_flush(struct bpf_map *map); +void __dev_map_flush(void); int dev_map_enqueue(struct bpf_dtab_netdev *dst, struct xdp_buff *xdp, struct net_device *dev_rx); int dev_map_generic_redirect(struct bpf_dtab_netdev *dst, struct sk_buff *skb, @@ -1068,7 +1068,7 @@ static inline struct net_device *__dev_map_hash_lookup_elem(struct bpf_map *map return NULL; } -static inline void __dev_map_flush(struct bpf_map *map) +static inline void __dev_map_flush(void) { } diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c index b7595de6a91a..da9c832fc5c8 100644 --- a/kernel/bpf/devmap.c +++ b/kernel/bpf/devmap.c @@ -75,7 +75,6 @@ struct bpf_dtab_netdev { struct bpf_dtab { struct bpf_map map; struct bpf_dtab_netdev **netdev_map; /* DEVMAP type only */ - struct list_head __percpu *flush_list; struct list_head list; /* these are only used for DEVMAP_HASH type maps */ @@ -85,6 +84,7 @@ struct bpf_dtab { u32 n_buckets; }; +static DEFINE_PER_CPU(struct list_head, dev_map_flush_list); static DEFINE_SPINLOCK(dev_map_lock); static LIST_HEAD(dev_map_list); @@ -109,8 +109,8 @@ static inline struct hlist_head *dev_map_index_hash(struct bpf_dtab *dtab, static int dev_map_init_map(struct bpf_dtab *dtab, union bpf_attr *attr) { - int err, cpu; - u64 cost; + u64 cost = 0; + int err; /* check sanity of attributes */ if (attr->max_entries == 0 || attr->key_size != 4 || @@ -125,9 +125,6 @@ static int dev_map_init_map(struct bpf_dtab *dtab, union bpf_attr *attr) bpf_map_init_from_attr(&dtab->map, attr); - /* make sure page count doesn't overflow */ - cost = (u64) sizeof(struct list_head) * num_possible_cpus(); - if (attr->map_type == BPF_MAP_TYPE_DEVMAP_HASH) { dtab->n_buckets = roundup_pow_of_two(dtab->map.max_entries); @@ -143,17 +140,10 @@ static int dev_map_init_map(struct bpf_dtab *dtab, union bpf_attr *attr) if (err) return -EINVAL; - dtab->flush_list = alloc_percpu(struct list_head); - if (!dtab->flush_list) - goto free_charge; - - for_each_possible_cpu(cpu) - INIT_LIST_HEAD(per_cpu_ptr(dtab->flush_list, cpu)); - if (attr->map_type == BPF_MAP_TYPE_DEVMAP_HASH) { dtab->dev_index_head = dev_map_create_hash(dtab->n_buckets); if (!dtab->dev_index_head) - goto free_percpu; + goto free_charge; spin_lock_init(&dtab->index_lock); } else { @@ -161,13 +151,11 @@ static int dev_map_init_map(struct bpf_dtab *dtab, union bpf_attr *attr) sizeof(struct bpf_dtab_netdev *), dtab->map.numa_node); if (!dtab->netdev_map) - goto free_percpu; + goto free_charge; } return 0; -free_percpu: - free_percpu(dtab->flush_list); free_charge: bpf_map_charge_finish(&dtab->map.memory); return -ENOMEM; @@ -254,7 +242,6 @@ static void dev_map_free(struct bpf_map *map) bpf_map_area_free(dtab->netdev_map); } - free_percpu(dtab->flush_list); kfree(dtab); } @@ -384,10 +371,9 @@ error: * net device can be torn down. On devmap tear down we ensure the flush list * is empty before completing to ensure all flush operations have completed. */ -void __dev_map_flush(struct bpf_map *map) +void __dev_map_flush(void) { - struct bpf_dtab *dtab = container_of(map, struct bpf_dtab, map); - struct list_head *flush_list = this_cpu_ptr(dtab->flush_list); + struct list_head *flush_list = this_cpu_ptr(&dev_map_flush_list); struct xdp_bulk_queue *bq, *tmp; rcu_read_lock(); @@ -419,7 +405,7 @@ static int bq_enqueue(struct bpf_dtab_netdev *obj, struct xdp_frame *xdpf, struct net_device *dev_rx) { - struct list_head *flush_list = this_cpu_ptr(obj->dtab->flush_list); + struct list_head *flush_list = this_cpu_ptr(&dev_map_flush_list); struct xdp_bulk_queue *bq = this_cpu_ptr(obj->bulkq); if (unlikely(bq->count == DEV_MAP_BULK_SIZE)) @@ -777,10 +763,15 @@ static struct notifier_block dev_map_notifier = { static int __init dev_map_init(void) { + int cpu; + /* Assure tracepoint shadow struct _bpf_dtab_netdev is in sync */ BUILD_BUG_ON(offsetof(struct bpf_dtab_netdev, dev) != offsetof(struct _bpf_dtab_netdev, dev)); register_netdevice_notifier(&dev_map_notifier); + + for_each_possible_cpu(cpu) + INIT_LIST_HEAD(&per_cpu(dev_map_flush_list, cpu)); return 0; } diff --git a/net/core/filter.c b/net/core/filter.c index c51678c473c5..b7570cb84902 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -3555,7 +3555,7 @@ void xdp_do_flush_map(void) switch (map->map_type) { case BPF_MAP_TYPE_DEVMAP: case BPF_MAP_TYPE_DEVMAP_HASH: - __dev_map_flush(map); + __dev_map_flush(); break; case BPF_MAP_TYPE_CPUMAP: __cpu_map_flush(map); -- cgit v1.2.3 From cdfafe98cabefeedbbc65af5c191c59745c03298 Mon Sep 17 00:00:00 2001 From: Björn Töpel Date: Thu, 19 Dec 2019 07:10:04 +0100 Subject: xdp: Make cpumap flush_list common for all map instances MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The cpumap flush list is used to track entries that need to flushed from via the xdp_do_flush_map() function. This list used to be per-map, but there is really no reason for that. Instead make the flush list global for all devmaps, which simplifies __cpu_map_flush() and cpu_map_alloc(). Signed-off-by: Björn Töpel Signed-off-by: Alexei Starovoitov Acked-by: Toke Høiland-Jørgensen Link: https://lore.kernel.org/bpf/20191219061006.21980-7-bjorn.topel@gmail.com --- include/linux/bpf.h | 4 ++-- kernel/bpf/cpumap.c | 36 ++++++++++++++++++------------------ net/core/filter.c | 2 +- 3 files changed, 21 insertions(+), 21 deletions(-) (limited to 'include') diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 31191804ca09..8f3e00c84f39 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -966,7 +966,7 @@ int dev_map_generic_redirect(struct bpf_dtab_netdev *dst, struct sk_buff *skb, struct bpf_prog *xdp_prog); struct bpf_cpu_map_entry *__cpu_map_lookup_elem(struct bpf_map *map, u32 key); -void __cpu_map_flush(struct bpf_map *map); +void __cpu_map_flush(void); int cpu_map_enqueue(struct bpf_cpu_map_entry *rcpu, struct xdp_buff *xdp, struct net_device *dev_rx); @@ -1097,7 +1097,7 @@ struct bpf_cpu_map_entry *__cpu_map_lookup_elem(struct bpf_map *map, u32 key) return NULL; } -static inline void __cpu_map_flush(struct bpf_map *map) +static inline void __cpu_map_flush(void) { } diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c index f9deed659798..70f71b154fa5 100644 --- a/kernel/bpf/cpumap.c +++ b/kernel/bpf/cpumap.c @@ -72,17 +72,18 @@ struct bpf_cpu_map { struct bpf_map map; /* Below members specific for map type */ struct bpf_cpu_map_entry **cpu_map; - struct list_head __percpu *flush_list; }; +static DEFINE_PER_CPU(struct list_head, cpu_map_flush_list); + static int bq_flush_to_queue(struct xdp_bulk_queue *bq); static struct bpf_map *cpu_map_alloc(union bpf_attr *attr) { struct bpf_cpu_map *cmap; int err = -ENOMEM; - int ret, cpu; u64 cost; + int ret; if (!capable(CAP_SYS_ADMIN)) return ERR_PTR(-EPERM); @@ -106,7 +107,6 @@ static struct bpf_map *cpu_map_alloc(union bpf_attr *attr) /* make sure page count doesn't overflow */ cost = (u64) cmap->map.max_entries * sizeof(struct bpf_cpu_map_entry *); - cost += sizeof(struct list_head) * num_possible_cpus(); /* Notice returns -EPERM on if map size is larger than memlock limit */ ret = bpf_map_charge_init(&cmap->map.memory, cost); @@ -115,23 +115,14 @@ static struct bpf_map *cpu_map_alloc(union bpf_attr *attr) goto free_cmap; } - cmap->flush_list = alloc_percpu(struct list_head); - if (!cmap->flush_list) - goto free_charge; - - for_each_possible_cpu(cpu) - INIT_LIST_HEAD(per_cpu_ptr(cmap->flush_list, cpu)); - /* Alloc array for possible remote "destination" CPUs */ cmap->cpu_map = bpf_map_area_alloc(cmap->map.max_entries * sizeof(struct bpf_cpu_map_entry *), cmap->map.numa_node); if (!cmap->cpu_map) - goto free_percpu; + goto free_charge; return &cmap->map; -free_percpu: - free_percpu(cmap->flush_list); free_charge: bpf_map_charge_finish(&cmap->map.memory); free_cmap: @@ -526,7 +517,6 @@ static void cpu_map_free(struct bpf_map *map) /* bq flush and cleanup happens after RCU grace-period */ __cpu_map_entry_replace(cmap, i, NULL); /* call_rcu */ } - free_percpu(cmap->flush_list); bpf_map_area_free(cmap->cpu_map); kfree(cmap); } @@ -618,7 +608,7 @@ static int bq_flush_to_queue(struct xdp_bulk_queue *bq) */ static int bq_enqueue(struct bpf_cpu_map_entry *rcpu, struct xdp_frame *xdpf) { - struct list_head *flush_list = this_cpu_ptr(rcpu->cmap->flush_list); + struct list_head *flush_list = this_cpu_ptr(&cpu_map_flush_list); struct xdp_bulk_queue *bq = this_cpu_ptr(rcpu->bulkq); if (unlikely(bq->count == CPU_MAP_BULK_SIZE)) @@ -657,10 +647,9 @@ int cpu_map_enqueue(struct bpf_cpu_map_entry *rcpu, struct xdp_buff *xdp, return 0; } -void __cpu_map_flush(struct bpf_map *map) +void __cpu_map_flush(void) { - struct bpf_cpu_map *cmap = container_of(map, struct bpf_cpu_map, map); - struct list_head *flush_list = this_cpu_ptr(cmap->flush_list); + struct list_head *flush_list = this_cpu_ptr(&cpu_map_flush_list); struct xdp_bulk_queue *bq, *tmp; list_for_each_entry_safe(bq, tmp, flush_list, flush_node) { @@ -670,3 +659,14 @@ void __cpu_map_flush(struct bpf_map *map) wake_up_process(bq->obj->kthread); } } + +static int __init cpu_map_init(void) +{ + int cpu; + + for_each_possible_cpu(cpu) + INIT_LIST_HEAD(&per_cpu(cpu_map_flush_list, cpu)); + return 0; +} + +subsys_initcall(cpu_map_init); diff --git a/net/core/filter.c b/net/core/filter.c index b7570cb84902..c706325b3e66 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -3558,7 +3558,7 @@ void xdp_do_flush_map(void) __dev_map_flush(); break; case BPF_MAP_TYPE_CPUMAP: - __cpu_map_flush(map); + __cpu_map_flush(); break; case BPF_MAP_TYPE_XSKMAP: __xsk_map_flush(); -- cgit v1.2.3 From 332f22a60e4c3492d4953cd6f7aaa4e8bd0bba97 Mon Sep 17 00:00:00 2001 From: Björn Töpel Date: Thu, 19 Dec 2019 07:10:05 +0100 Subject: xdp: Remove map_to_flush and map swap detection MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Now that all XDP maps that can be used with bpf_redirect_map() tracks entries to be flushed in a global fashion, there is not need to track that the map has changed and flush from xdp_do_generic_map() anymore. All entries will be flushed in xdp_do_flush_map(). This means that the map_to_flush can be removed, and the corresponding checks. Moving the flush logic to one place, xdp_do_flush_map(), give a bulking behavior and performance boost. Signed-off-by: Björn Töpel Signed-off-by: Alexei Starovoitov Acked-by: Toke Høiland-Jørgensen Link: https://lore.kernel.org/bpf/20191219061006.21980-8-bjorn.topel@gmail.com --- include/linux/filter.h | 1 - net/core/filter.c | 27 +++------------------------ 2 files changed, 3 insertions(+), 25 deletions(-) (limited to 'include') diff --git a/include/linux/filter.h b/include/linux/filter.h index 37ac7025031d..69d6706fc889 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -592,7 +592,6 @@ struct bpf_redirect_info { u32 tgt_index; void *tgt_value; struct bpf_map *map; - struct bpf_map *map_to_flush; u32 kern_flags; }; diff --git a/net/core/filter.c b/net/core/filter.c index c706325b3e66..d9caa3e57ea1 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -3547,26 +3547,9 @@ static int __bpf_tx_xdp_map(struct net_device *dev_rx, void *fwd, void xdp_do_flush_map(void) { - struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); - struct bpf_map *map = ri->map_to_flush; - - ri->map_to_flush = NULL; - if (map) { - switch (map->map_type) { - case BPF_MAP_TYPE_DEVMAP: - case BPF_MAP_TYPE_DEVMAP_HASH: - __dev_map_flush(); - break; - case BPF_MAP_TYPE_CPUMAP: - __cpu_map_flush(); - break; - case BPF_MAP_TYPE_XSKMAP: - __xsk_map_flush(); - break; - default: - break; - } - } + __dev_map_flush(); + __cpu_map_flush(); + __xsk_map_flush(); } EXPORT_SYMBOL_GPL(xdp_do_flush_map); @@ -3615,14 +3598,10 @@ static int xdp_do_redirect_map(struct net_device *dev, struct xdp_buff *xdp, ri->tgt_value = NULL; WRITE_ONCE(ri->map, NULL); - if (ri->map_to_flush && unlikely(ri->map_to_flush != map)) - xdp_do_flush_map(); - err = __bpf_tx_xdp_map(dev, fwd, map, xdp); if (unlikely(err)) goto err; - ri->map_to_flush = map; _trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index); return 0; err: -- cgit v1.2.3 From 7dd68b3279f1792103d12e69933db3128c6d416e Mon Sep 17 00:00:00 2001 From: Andrey Ignatov Date: Wed, 18 Dec 2019 23:44:35 -0800 Subject: bpf: Support replacing cgroup-bpf program in MULTI mode The common use-case in production is to have multiple cgroup-bpf programs per attach type that cover multiple use-cases. Such programs are attached with BPF_F_ALLOW_MULTI and can be maintained by different people. Order of programs usually matters, for example imagine two egress programs: the first one drops packets and the second one counts packets. If they're swapped the result of counting program will be different. It brings operational challenges with updating cgroup-bpf program(s) attached with BPF_F_ALLOW_MULTI since there is no way to replace a program: * One way to update is to detach all programs first and then attach the new version(s) again in the right order. This introduces an interruption in the work a program is doing and may not be acceptable (e.g. if it's egress firewall); * Another way is attach the new version of a program first and only then detach the old version. This introduces the time interval when two versions of same program are working, what may not be acceptable if a program is not idempotent. It also imposes additional burden on program developers to make sure that two versions of their program can co-exist. Solve the problem by introducing a "replace" mode in BPF_PROG_ATTACH command for cgroup-bpf programs being attached with BPF_F_ALLOW_MULTI flag. This mode is enabled by newly introduced BPF_F_REPLACE attach flag and bpf_attr.replace_bpf_fd attribute to pass fd of the old program to replace That way user can replace any program among those attached with BPF_F_ALLOW_MULTI flag without the problems described above. Details of the new API: * If BPF_F_REPLACE is set but replace_bpf_fd doesn't have valid descriptor of BPF program, BPF_PROG_ATTACH will return corresponding error (EINVAL or EBADF). * If replace_bpf_fd has valid descriptor of BPF program but such a program is not attached to specified cgroup, BPF_PROG_ATTACH will return ENOENT. BPF_F_REPLACE is introduced to make the user intent clear, since replace_bpf_fd alone can't be used for this (its default value, 0, is a valid fd). BPF_F_REPLACE also makes it possible to extend the API in the future (e.g. add BPF_F_BEFORE and BPF_F_AFTER if needed). Signed-off-by: Andrey Ignatov Signed-off-by: Alexei Starovoitov Acked-by: Martin KaFai Lau Acked-by: Andrii Narkyiko Link: https://lore.kernel.org/bpf/30cd850044a0057bdfcaaf154b7d2f39850ba813.1576741281.git.rdna@fb.com --- include/linux/bpf-cgroup.h | 4 +++- include/uapi/linux/bpf.h | 10 ++++++++++ kernel/bpf/cgroup.c | 30 ++++++++++++++++++++++++++---- kernel/bpf/syscall.c | 4 ++-- kernel/cgroup/cgroup.c | 5 +++-- tools/include/uapi/linux/bpf.h | 10 ++++++++++ 6 files changed, 54 insertions(+), 9 deletions(-) (limited to 'include') diff --git a/include/linux/bpf-cgroup.h b/include/linux/bpf-cgroup.h index 169fd25f6bc2..18f6a6da7c3c 100644 --- a/include/linux/bpf-cgroup.h +++ b/include/linux/bpf-cgroup.h @@ -85,6 +85,7 @@ int cgroup_bpf_inherit(struct cgroup *cgrp); void cgroup_bpf_offline(struct cgroup *cgrp); int __cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog, + struct bpf_prog *replace_prog, enum bpf_attach_type type, u32 flags); int __cgroup_bpf_detach(struct cgroup *cgrp, struct bpf_prog *prog, enum bpf_attach_type type); @@ -93,7 +94,8 @@ int __cgroup_bpf_query(struct cgroup *cgrp, const union bpf_attr *attr, /* Wrapper for __cgroup_bpf_*() protected by cgroup_mutex */ int cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog, - enum bpf_attach_type type, u32 flags); + struct bpf_prog *replace_prog, enum bpf_attach_type type, + u32 flags); int cgroup_bpf_detach(struct cgroup *cgrp, struct bpf_prog *prog, enum bpf_attach_type type, u32 flags); int cgroup_bpf_query(struct cgroup *cgrp, const union bpf_attr *attr, diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index dbbcf0b02970..7df436da542d 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -231,6 +231,11 @@ enum bpf_attach_type { * When children program makes decision (like picking TCP CA or sock bind) * parent program has a chance to override it. * + * With BPF_F_ALLOW_MULTI a new program is added to the end of the list of + * programs for a cgroup. Though it's possible to replace an old program at + * any position by also specifying BPF_F_REPLACE flag and position itself in + * replace_bpf_fd attribute. Old program at this position will be released. + * * A cgroup with MULTI or OVERRIDE flag allows any attach flags in sub-cgroups. * A cgroup with NONE doesn't allow any programs in sub-cgroups. * Ex1: @@ -249,6 +254,7 @@ enum bpf_attach_type { */ #define BPF_F_ALLOW_OVERRIDE (1U << 0) #define BPF_F_ALLOW_MULTI (1U << 1) +#define BPF_F_REPLACE (1U << 2) /* If BPF_F_STRICT_ALIGNMENT is used in BPF_PROG_LOAD command, the * verifier will perform strict alignment checking as if the kernel @@ -442,6 +448,10 @@ union bpf_attr { __u32 attach_bpf_fd; /* eBPF program to attach */ __u32 attach_type; __u32 attach_flags; + __u32 replace_bpf_fd; /* previously attached eBPF + * program to replace if + * BPF_F_REPLACE is used + */ }; struct { /* anonymous struct used by BPF_PROG_TEST_RUN command */ diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c index 283efe3ce052..45346c79613a 100644 --- a/kernel/bpf/cgroup.c +++ b/kernel/bpf/cgroup.c @@ -282,14 +282,17 @@ cleanup: * propagate the change to descendants * @cgrp: The cgroup which descendants to traverse * @prog: A program to attach + * @replace_prog: Previously attached program to replace if BPF_F_REPLACE is set * @type: Type of attach operation * @flags: Option flags * * Must be called with cgroup_mutex held. */ int __cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog, + struct bpf_prog *replace_prog, enum bpf_attach_type type, u32 flags) { + u32 saved_flags = (flags & (BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI)); struct list_head *progs = &cgrp->bpf.progs[type]; struct bpf_prog *old_prog = NULL; struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE], @@ -298,14 +301,15 @@ int __cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog, enum bpf_cgroup_storage_type stype; int err; - if ((flags & BPF_F_ALLOW_OVERRIDE) && (flags & BPF_F_ALLOW_MULTI)) + if (((flags & BPF_F_ALLOW_OVERRIDE) && (flags & BPF_F_ALLOW_MULTI)) || + ((flags & BPF_F_REPLACE) && !(flags & BPF_F_ALLOW_MULTI))) /* invalid combination */ return -EINVAL; if (!hierarchy_allows_attach(cgrp, type)) return -EPERM; - if (!list_empty(progs) && cgrp->bpf.flags[type] != flags) + if (!list_empty(progs) && cgrp->bpf.flags[type] != saved_flags) /* Disallow attaching non-overridable on top * of existing overridable in this cgroup. * Disallow attaching multi-prog if overridable or none @@ -320,7 +324,12 @@ int __cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog, if (pl->prog == prog) /* disallow attaching the same prog twice */ return -EINVAL; + if (pl->prog == replace_prog) + replace_pl = pl; } + if ((flags & BPF_F_REPLACE) && !replace_pl) + /* prog to replace not found for cgroup */ + return -ENOENT; } else if (!list_empty(progs)) { replace_pl = list_first_entry(progs, typeof(*pl), node); } @@ -356,7 +365,7 @@ int __cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog, for_each_cgroup_storage_type(stype) pl->storage[stype] = storage[stype]; - cgrp->bpf.flags[type] = flags; + cgrp->bpf.flags[type] = saved_flags; err = update_effective_progs(cgrp, type); if (err) @@ -522,6 +531,7 @@ int __cgroup_bpf_query(struct cgroup *cgrp, const union bpf_attr *attr, int cgroup_bpf_prog_attach(const union bpf_attr *attr, enum bpf_prog_type ptype, struct bpf_prog *prog) { + struct bpf_prog *replace_prog = NULL; struct cgroup *cgrp; int ret; @@ -529,8 +539,20 @@ int cgroup_bpf_prog_attach(const union bpf_attr *attr, if (IS_ERR(cgrp)) return PTR_ERR(cgrp); - ret = cgroup_bpf_attach(cgrp, prog, attr->attach_type, + if ((attr->attach_flags & BPF_F_ALLOW_MULTI) && + (attr->attach_flags & BPF_F_REPLACE)) { + replace_prog = bpf_prog_get_type(attr->replace_bpf_fd, ptype); + if (IS_ERR(replace_prog)) { + cgroup_put(cgrp); + return PTR_ERR(replace_prog); + } + } + + ret = cgroup_bpf_attach(cgrp, prog, replace_prog, attr->attach_type, attr->attach_flags); + + if (replace_prog) + bpf_prog_put(replace_prog); cgroup_put(cgrp); return ret; } diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index b08c362f4e02..81ee8595dfee 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -2073,10 +2073,10 @@ static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog, } } -#define BPF_PROG_ATTACH_LAST_FIELD attach_flags +#define BPF_PROG_ATTACH_LAST_FIELD replace_bpf_fd #define BPF_F_ATTACH_MASK \ - (BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI) + (BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI | BPF_F_REPLACE) static int bpf_prog_attach(const union bpf_attr *attr) { diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index 735af8f15f95..725365df066d 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -6288,12 +6288,13 @@ void cgroup_sk_free(struct sock_cgroup_data *skcd) #ifdef CONFIG_CGROUP_BPF int cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog, - enum bpf_attach_type type, u32 flags) + struct bpf_prog *replace_prog, enum bpf_attach_type type, + u32 flags) { int ret; mutex_lock(&cgroup_mutex); - ret = __cgroup_bpf_attach(cgrp, prog, type, flags); + ret = __cgroup_bpf_attach(cgrp, prog, replace_prog, type, flags); mutex_unlock(&cgroup_mutex); return ret; } diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index dbbcf0b02970..7df436da542d 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -231,6 +231,11 @@ enum bpf_attach_type { * When children program makes decision (like picking TCP CA or sock bind) * parent program has a chance to override it. * + * With BPF_F_ALLOW_MULTI a new program is added to the end of the list of + * programs for a cgroup. Though it's possible to replace an old program at + * any position by also specifying BPF_F_REPLACE flag and position itself in + * replace_bpf_fd attribute. Old program at this position will be released. + * * A cgroup with MULTI or OVERRIDE flag allows any attach flags in sub-cgroups. * A cgroup with NONE doesn't allow any programs in sub-cgroups. * Ex1: @@ -249,6 +254,7 @@ enum bpf_attach_type { */ #define BPF_F_ALLOW_OVERRIDE (1U << 0) #define BPF_F_ALLOW_MULTI (1U << 1) +#define BPF_F_REPLACE (1U << 2) /* If BPF_F_STRICT_ALIGNMENT is used in BPF_PROG_LOAD command, the * verifier will perform strict alignment checking as if the kernel @@ -442,6 +448,10 @@ union bpf_attr { __u32 attach_bpf_fd; /* eBPF program to attach */ __u32 attach_type; __u32 attach_flags; + __u32 replace_bpf_fd; /* previously attached eBPF + * program to replace if + * BPF_F_REPLACE is used + */ }; struct { /* anonymous struct used by BPF_PROG_TEST_RUN command */ -- cgit v1.2.3 From 03896ef1f0cb23d2742ddf486c531c700a2da7d6 Mon Sep 17 00:00:00 2001 From: Magnus Karlsson Date: Thu, 19 Dec 2019 13:39:27 +0100 Subject: xsk: Change names of validation functions Change the names of the validation functions to better reflect what they are doing. The uppermost ones are reading entries from the rings and only the bottom ones validate entries. So xskq_cons_read_ is a better prefix name. Also change the xskq_cons_read_ functions to return a bool as the the descriptor or address is already returned by reference in the parameters. Everyone is using the return value as a bool anyway. Signed-off-by: Magnus Karlsson Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/1576759171-28550-9-git-send-email-magnus.karlsson@intel.com --- include/net/xdp_sock.h | 4 ++-- net/xdp/xsk.c | 4 ++-- net/xdp/xsk_queue.h | 59 ++++++++++++++++++++++++++------------------------ 3 files changed, 35 insertions(+), 32 deletions(-) (limited to 'include') diff --git a/include/net/xdp_sock.h b/include/net/xdp_sock.h index 48594740d67c..63f005830866 100644 --- a/include/net/xdp_sock.h +++ b/include/net/xdp_sock.h @@ -118,7 +118,7 @@ int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp); bool xsk_is_setup_for_bpf_map(struct xdp_sock *xs); /* Used from netdev driver */ bool xsk_umem_has_addrs(struct xdp_umem *umem, u32 cnt); -u64 *xsk_umem_peek_addr(struct xdp_umem *umem, u64 *addr); +bool xsk_umem_peek_addr(struct xdp_umem *umem, u64 *addr); void xsk_umem_discard_addr(struct xdp_umem *umem); void xsk_umem_complete_tx(struct xdp_umem *umem, u32 nb_entries); bool xsk_umem_consume_tx(struct xdp_umem *umem, struct xdp_desc *desc); @@ -197,7 +197,7 @@ static inline bool xsk_umem_has_addrs_rq(struct xdp_umem *umem, u32 cnt) return xsk_umem_has_addrs(umem, cnt - rq->length); } -static inline u64 *xsk_umem_peek_addr_rq(struct xdp_umem *umem, u64 *addr) +static inline bool xsk_umem_peek_addr_rq(struct xdp_umem *umem, u64 *addr) { struct xdp_umem_fq_reuse *rq = umem->fq_reuse; diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c index cd84b9d0f1e1..4e932a930b3a 100644 --- a/net/xdp/xsk.c +++ b/net/xdp/xsk.c @@ -45,7 +45,7 @@ bool xsk_umem_has_addrs(struct xdp_umem *umem, u32 cnt) } EXPORT_SYMBOL(xsk_umem_has_addrs); -u64 *xsk_umem_peek_addr(struct xdp_umem *umem, u64 *addr) +bool xsk_umem_peek_addr(struct xdp_umem *umem, u64 *addr) { return xskq_cons_peek_addr(umem->fq, addr, umem); } @@ -126,7 +126,7 @@ static void __xsk_rcv_memcpy(struct xdp_umem *umem, u64 addr, void *from_buf, void *to_buf = xdp_umem_get_data(umem, addr); addr = xsk_umem_add_offset_to_addr(addr); - if (xskq_crosses_non_contig_pg(umem, addr, len + metalen)) { + if (xskq_cons_crosses_non_contig_pg(umem, addr, len + metalen)) { void *next_pg_addr = umem->pages[(addr >> PAGE_SHIFT) + 1].addr; u64 page_start = addr & ~(PAGE_SIZE - 1); u64 first_len = PAGE_SIZE - (addr - page_start); diff --git a/net/xdp/xsk_queue.h b/net/xdp/xsk_queue.h index 1436116767ea..6d04a96dd092 100644 --- a/net/xdp/xsk_queue.h +++ b/net/xdp/xsk_queue.h @@ -136,8 +136,9 @@ static inline bool xskq_cons_has_entries(struct xsk_queue *q, u32 cnt) /* UMEM queue */ -static inline bool xskq_crosses_non_contig_pg(struct xdp_umem *umem, u64 addr, - u64 length) +static inline bool xskq_cons_crosses_non_contig_pg(struct xdp_umem *umem, + u64 addr, + u64 length) { bool cross_pg = (addr & (PAGE_SIZE - 1)) + length > PAGE_SIZE; bool next_pg_contig = @@ -147,7 +148,7 @@ static inline bool xskq_crosses_non_contig_pg(struct xdp_umem *umem, u64 addr, return cross_pg && !next_pg_contig; } -static inline bool xskq_is_valid_addr(struct xsk_queue *q, u64 addr) +static inline bool xskq_cons_is_valid_addr(struct xsk_queue *q, u64 addr) { if (addr >= q->size) { q->invalid_descs++; @@ -157,7 +158,8 @@ static inline bool xskq_is_valid_addr(struct xsk_queue *q, u64 addr) return true; } -static inline bool xskq_is_valid_addr_unaligned(struct xsk_queue *q, u64 addr, +static inline bool xskq_cons_is_valid_unaligned(struct xsk_queue *q, + u64 addr, u64 length, struct xdp_umem *umem) { @@ -165,7 +167,7 @@ static inline bool xskq_is_valid_addr_unaligned(struct xsk_queue *q, u64 addr, addr = xsk_umem_add_offset_to_addr(addr); if (base_addr >= q->size || addr >= q->size || - xskq_crosses_non_contig_pg(umem, addr, length)) { + xskq_cons_crosses_non_contig_pg(umem, addr, length)) { q->invalid_descs++; return false; } @@ -173,8 +175,8 @@ static inline bool xskq_is_valid_addr_unaligned(struct xsk_queue *q, u64 addr, return true; } -static inline u64 *xskq_validate_addr(struct xsk_queue *q, u64 *addr, - struct xdp_umem *umem) +static inline bool xskq_cons_read_addr(struct xsk_queue *q, u64 *addr, + struct xdp_umem *umem) { struct xdp_umem_ring *ring = (struct xdp_umem_ring *)q->ring; @@ -184,29 +186,29 @@ static inline u64 *xskq_validate_addr(struct xsk_queue *q, u64 *addr, *addr = READ_ONCE(ring->desc[idx]) & q->chunk_mask; if (umem->flags & XDP_UMEM_UNALIGNED_CHUNK_FLAG) { - if (xskq_is_valid_addr_unaligned(q, *addr, + if (xskq_cons_is_valid_unaligned(q, *addr, umem->chunk_size_nohr, umem)) - return addr; + return true; goto out; } - if (xskq_is_valid_addr(q, *addr)) - return addr; + if (xskq_cons_is_valid_addr(q, *addr)) + return true; out: q->cached_cons++; } - return NULL; + return false; } -static inline u64 *xskq_cons_peek_addr(struct xsk_queue *q, u64 *addr, +static inline bool xskq_cons_peek_addr(struct xsk_queue *q, u64 *addr, struct xdp_umem *umem) { if (q->cached_prod == q->cached_cons) xskq_cons_get_entries(q); - return xskq_validate_addr(q, addr, umem); + return xskq_cons_read_addr(q, addr, umem); } static inline void xskq_cons_release(struct xsk_queue *q) @@ -270,11 +272,12 @@ static inline void xskq_prod_submit_n(struct xsk_queue *q, u32 nb_entries) /* Rx/Tx queue */ -static inline bool xskq_is_valid_desc(struct xsk_queue *q, struct xdp_desc *d, - struct xdp_umem *umem) +static inline bool xskq_cons_is_valid_desc(struct xsk_queue *q, + struct xdp_desc *d, + struct xdp_umem *umem) { if (umem->flags & XDP_UMEM_UNALIGNED_CHUNK_FLAG) { - if (!xskq_is_valid_addr_unaligned(q, d->addr, d->len, umem)) + if (!xskq_cons_is_valid_unaligned(q, d->addr, d->len, umem)) return false; if (d->len > umem->chunk_size_nohr || d->options) { @@ -285,7 +288,7 @@ static inline bool xskq_is_valid_desc(struct xsk_queue *q, struct xdp_desc *d, return true; } - if (!xskq_is_valid_addr(q, d->addr)) + if (!xskq_cons_is_valid_addr(q, d->addr)) return false; if (((d->addr + d->len) & q->chunk_mask) != (d->addr & q->chunk_mask) || @@ -297,31 +300,31 @@ static inline bool xskq_is_valid_desc(struct xsk_queue *q, struct xdp_desc *d, return true; } -static inline struct xdp_desc *xskq_validate_desc(struct xsk_queue *q, - struct xdp_desc *desc, - struct xdp_umem *umem) +static inline bool xskq_cons_read_desc(struct xsk_queue *q, + struct xdp_desc *desc, + struct xdp_umem *umem) { while (q->cached_cons != q->cached_prod) { struct xdp_rxtx_ring *ring = (struct xdp_rxtx_ring *)q->ring; u32 idx = q->cached_cons & q->ring_mask; *desc = READ_ONCE(ring->desc[idx]); - if (xskq_is_valid_desc(q, desc, umem)) - return desc; + if (xskq_cons_is_valid_desc(q, desc, umem)) + return true; q->cached_cons++; } - return NULL; + return false; } -static inline struct xdp_desc *xskq_cons_peek_desc(struct xsk_queue *q, - struct xdp_desc *desc, - struct xdp_umem *umem) +static inline bool xskq_cons_peek_desc(struct xsk_queue *q, + struct xdp_desc *desc, + struct xdp_umem *umem) { if (q->cached_prod == q->cached_cons) xskq_cons_get_entries(q); - return xskq_validate_desc(q, desc, umem); + return xskq_cons_read_desc(q, desc, umem); } static inline int xskq_prod_reserve_desc(struct xsk_queue *q, -- cgit v1.2.3 From f8509aa078de0842ec1817e8026e58620cd05d3b Mon Sep 17 00:00:00 2001 From: Magnus Karlsson Date: Thu, 19 Dec 2019 13:39:28 +0100 Subject: xsk: ixgbe: i40e: ice: mlx5: Xsk_umem_discard_addr to xsk_umem_release_addr Change the name of xsk_umem_discard_addr to xsk_umem_release_addr to better reflect the new naming of the AF_XDP queue manipulation functions. As this functions is used by drivers implementing support for AF_XDP zero-copy, it requires a name change to these drivers. The function xsk_umem_release_addr_rq has also changed name in the same fashion. Signed-off-by: Magnus Karlsson Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/1576759171-28550-10-git-send-email-magnus.karlsson@intel.com --- drivers/net/ethernet/intel/i40e/i40e_xsk.c | 4 ++-- drivers/net/ethernet/intel/ice/ice_xsk.c | 4 ++-- drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c | 4 ++-- drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.c | 2 +- include/net/xdp_sock.h | 10 +++++----- net/xdp/xsk.c | 4 ++-- 6 files changed, 14 insertions(+), 14 deletions(-) (limited to 'include') diff --git a/drivers/net/ethernet/intel/i40e/i40e_xsk.c b/drivers/net/ethernet/intel/i40e/i40e_xsk.c index d07e1a890428..20d6f11a3468 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_xsk.c +++ b/drivers/net/ethernet/intel/i40e/i40e_xsk.c @@ -269,7 +269,7 @@ static bool i40e_alloc_buffer_zc(struct i40e_ring *rx_ring, bi->handle = xsk_umem_adjust_offset(umem, handle, umem->headroom); - xsk_umem_discard_addr(umem); + xsk_umem_release_addr(umem); return true; } @@ -306,7 +306,7 @@ static bool i40e_alloc_buffer_slow_zc(struct i40e_ring *rx_ring, bi->handle = xsk_umem_adjust_offset(umem, handle, umem->headroom); - xsk_umem_discard_addr_rq(umem); + xsk_umem_release_addr_rq(umem); return true; } diff --git a/drivers/net/ethernet/intel/ice/ice_xsk.c b/drivers/net/ethernet/intel/ice/ice_xsk.c index cf9b8b22d24f..0af1f0b951c0 100644 --- a/drivers/net/ethernet/intel/ice/ice_xsk.c +++ b/drivers/net/ethernet/intel/ice/ice_xsk.c @@ -555,7 +555,7 @@ ice_alloc_buf_fast_zc(struct ice_ring *rx_ring, struct ice_rx_buf *rx_buf) rx_buf->handle = handle + umem->headroom; - xsk_umem_discard_addr(umem); + xsk_umem_release_addr(umem); return true; } @@ -591,7 +591,7 @@ ice_alloc_buf_slow_zc(struct ice_ring *rx_ring, struct ice_rx_buf *rx_buf) rx_buf->handle = handle + umem->headroom; - xsk_umem_discard_addr_rq(umem); + xsk_umem_release_addr_rq(umem); return true; } diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c index d6feaacfbf89..1501d0a22078 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c @@ -277,7 +277,7 @@ static bool ixgbe_alloc_buffer_zc(struct ixgbe_ring *rx_ring, bi->handle = xsk_umem_adjust_offset(umem, handle, umem->headroom); - xsk_umem_discard_addr(umem); + xsk_umem_release_addr(umem); return true; } @@ -304,7 +304,7 @@ static bool ixgbe_alloc_buffer_slow_zc(struct ixgbe_ring *rx_ring, bi->handle = xsk_umem_adjust_offset(umem, handle, umem->headroom); - xsk_umem_discard_addr_rq(umem); + xsk_umem_release_addr_rq(umem); return true; } diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.c b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.c index 475b6bd5d29b..62fc8a128a8d 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.c @@ -35,7 +35,7 @@ int mlx5e_xsk_page_alloc_umem(struct mlx5e_rq *rq, */ dma_info->addr = xdp_umem_get_dma(umem, handle); - xsk_umem_discard_addr_rq(umem); + xsk_umem_release_addr_rq(umem); dma_sync_single_for_device(rq->pdev, dma_info->addr, PAGE_SIZE, DMA_BIDIRECTIONAL); diff --git a/include/net/xdp_sock.h b/include/net/xdp_sock.h index 63f005830866..e86ec48ef627 100644 --- a/include/net/xdp_sock.h +++ b/include/net/xdp_sock.h @@ -119,7 +119,7 @@ bool xsk_is_setup_for_bpf_map(struct xdp_sock *xs); /* Used from netdev driver */ bool xsk_umem_has_addrs(struct xdp_umem *umem, u32 cnt); bool xsk_umem_peek_addr(struct xdp_umem *umem, u64 *addr); -void xsk_umem_discard_addr(struct xdp_umem *umem); +void xsk_umem_release_addr(struct xdp_umem *umem); void xsk_umem_complete_tx(struct xdp_umem *umem, u32 nb_entries); bool xsk_umem_consume_tx(struct xdp_umem *umem, struct xdp_desc *desc); void xsk_umem_consume_tx_done(struct xdp_umem *umem); @@ -208,12 +208,12 @@ static inline bool xsk_umem_peek_addr_rq(struct xdp_umem *umem, u64 *addr) return addr; } -static inline void xsk_umem_discard_addr_rq(struct xdp_umem *umem) +static inline void xsk_umem_release_addr_rq(struct xdp_umem *umem) { struct xdp_umem_fq_reuse *rq = umem->fq_reuse; if (!rq->length) - xsk_umem_discard_addr(umem); + xsk_umem_release_addr(umem); else rq->length--; } @@ -258,7 +258,7 @@ static inline u64 *xsk_umem_peek_addr(struct xdp_umem *umem, u64 *addr) return NULL; } -static inline void xsk_umem_discard_addr(struct xdp_umem *umem) +static inline void xsk_umem_release_addr(struct xdp_umem *umem) { } @@ -332,7 +332,7 @@ static inline u64 *xsk_umem_peek_addr_rq(struct xdp_umem *umem, u64 *addr) return NULL; } -static inline void xsk_umem_discard_addr_rq(struct xdp_umem *umem) +static inline void xsk_umem_release_addr_rq(struct xdp_umem *umem) { } diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c index 4e932a930b3a..55092feeaf36 100644 --- a/net/xdp/xsk.c +++ b/net/xdp/xsk.c @@ -51,11 +51,11 @@ bool xsk_umem_peek_addr(struct xdp_umem *umem, u64 *addr) } EXPORT_SYMBOL(xsk_umem_peek_addr); -void xsk_umem_discard_addr(struct xdp_umem *umem) +void xsk_umem_release_addr(struct xdp_umem *umem) { xskq_cons_release(umem->fq); } -EXPORT_SYMBOL(xsk_umem_discard_addr); +EXPORT_SYMBOL(xsk_umem_release_addr); void xsk_set_rx_need_wakeup(struct xdp_umem *umem) { -- cgit v1.2.3