diff options
Diffstat (limited to 'tools/lib')
34 files changed, 2088 insertions, 464 deletions
diff --git a/tools/lib/api/io.h b/tools/lib/api/io.h index 84adf8102018..d3eb04d1bc89 100644 --- a/tools/lib/api/io.h +++ b/tools/lib/api/io.h @@ -43,48 +43,55 @@ static inline void io__init(struct io *io, int fd, io->eof = false; } -/* Reads one character from the "io" file with similar semantics to fgetc. */ -static inline int io__get_char(struct io *io) +/* Read from fd filling the buffer. Called when io->data == io->end. */ +static inline int io__fill_buffer(struct io *io) { - char *ptr = io->data; + ssize_t n; if (io->eof) return -1; - if (ptr == io->end) { - ssize_t n; - - if (io->timeout_ms != 0) { - struct pollfd pfds[] = { - { - .fd = io->fd, - .events = POLLIN, - }, - }; - - n = poll(pfds, 1, io->timeout_ms); - if (n == 0) - errno = ETIMEDOUT; - if (n > 0 && !(pfds[0].revents & POLLIN)) { - errno = EIO; - n = -1; - } - if (n <= 0) { - io->eof = true; - return -1; - } + if (io->timeout_ms != 0) { + struct pollfd pfds[] = { + { + .fd = io->fd, + .events = POLLIN, + }, + }; + + n = poll(pfds, 1, io->timeout_ms); + if (n == 0) + errno = ETIMEDOUT; + if (n > 0 && !(pfds[0].revents & POLLIN)) { + errno = EIO; + n = -1; } - n = read(io->fd, io->buf, io->buf_len); - if (n <= 0) { io->eof = true; return -1; } - ptr = &io->buf[0]; - io->end = &io->buf[n]; } - io->data = ptr + 1; - return *ptr; + n = read(io->fd, io->buf, io->buf_len); + + if (n <= 0) { + io->eof = true; + return -1; + } + io->data = &io->buf[0]; + io->end = &io->buf[n]; + return 0; +} + +/* Reads one character from the "io" file with similar semantics to fgetc. */ +static inline int io__get_char(struct io *io) +{ + if (io->data == io->end) { + int ret = io__fill_buffer(io); + + if (ret) + return ret; + } + return *io->data++; } /* Read a hexadecimal value with no 0x prefix into the out argument hex. If the diff --git a/tools/lib/bitmap.c b/tools/lib/bitmap.c index c3e4871967bc..2178862bb114 100644 --- a/tools/lib/bitmap.c +++ b/tools/lib/bitmap.c @@ -100,3 +100,23 @@ bool __bitmap_intersects(const unsigned long *bitmap1, return true; return false; } + +void __bitmap_clear(unsigned long *map, unsigned int start, int len) +{ + unsigned long *p = map + BIT_WORD(start); + const unsigned int size = start + len; + int bits_to_clear = BITS_PER_LONG - (start % BITS_PER_LONG); + unsigned long mask_to_clear = BITMAP_FIRST_WORD_MASK(start); + + while (len - bits_to_clear >= 0) { + *p &= ~mask_to_clear; + len -= bits_to_clear; + bits_to_clear = BITS_PER_LONG; + mask_to_clear = ~0UL; + p++; + } + if (len) { + mask_to_clear &= BITMAP_LAST_WORD_MASK(size); + *p &= ~mask_to_clear; + } +} diff --git a/tools/lib/bpf/Build b/tools/lib/bpf/Build index b6619199a706..e2cd558ca0b4 100644 --- a/tools/lib/bpf/Build +++ b/tools/lib/bpf/Build @@ -1,4 +1,4 @@ libbpf-y := libbpf.o bpf.o nlattr.o btf.o libbpf_errno.o str_error.o \ netlink.o bpf_prog_linfo.o libbpf_probes.o hashmap.o \ btf_dump.o ringbuf.o strset.o linker.o gen_loader.o relo_core.o \ - usdt.o zip.o elf.o features.o + usdt.o zip.o elf.o features.o btf_iter.o btf_relocate.o diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index 97ec005c3c47..2a4c71501a17 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -105,7 +105,7 @@ int sys_bpf_prog_load(union bpf_attr *attr, unsigned int size, int attempts) */ int probe_memcg_account(int token_fd) { - const size_t attr_sz = offsetofend(union bpf_attr, attach_btf_obj_fd); + const size_t attr_sz = offsetofend(union bpf_attr, prog_token_fd); struct bpf_insn insns[] = { BPF_EMIT_CALL(BPF_FUNC_ktime_get_coarse_ns), BPF_EXIT_INSN(), @@ -766,6 +766,7 @@ int bpf_link_create(int prog_fd, int target_fd, return libbpf_err(-EINVAL); break; case BPF_TRACE_KPROBE_MULTI: + case BPF_TRACE_KPROBE_SESSION: attr.link_create.kprobe_multi.flags = OPTS_GET(opts, kprobe_multi.flags, 0); attr.link_create.kprobe_multi.cnt = OPTS_GET(opts, kprobe_multi.cnt, 0); attr.link_create.kprobe_multi.syms = ptr_to_u64(OPTS_GET(opts, kprobe_multi.syms, 0)); @@ -785,6 +786,7 @@ int bpf_link_create(int prog_fd, int target_fd, if (!OPTS_ZEROED(opts, uprobe_multi)) return libbpf_err(-EINVAL); break; + case BPF_TRACE_RAW_TP: case BPF_TRACE_FENTRY: case BPF_TRACE_FEXIT: case BPF_MODIFY_RETURN: @@ -1173,20 +1175,31 @@ int bpf_link_get_info_by_fd(int link_fd, struct bpf_link_info *info, __u32 *info return bpf_obj_get_info_by_fd(link_fd, info, info_len); } -int bpf_raw_tracepoint_open(const char *name, int prog_fd) +int bpf_raw_tracepoint_open_opts(int prog_fd, struct bpf_raw_tp_opts *opts) { const size_t attr_sz = offsetofend(union bpf_attr, raw_tracepoint); union bpf_attr attr; int fd; + if (!OPTS_VALID(opts, bpf_raw_tp_opts)) + return libbpf_err(-EINVAL); + memset(&attr, 0, attr_sz); - attr.raw_tracepoint.name = ptr_to_u64(name); attr.raw_tracepoint.prog_fd = prog_fd; + attr.raw_tracepoint.name = ptr_to_u64(OPTS_GET(opts, tp_name, NULL)); + attr.raw_tracepoint.cookie = OPTS_GET(opts, cookie, 0); fd = sys_bpf_fd(BPF_RAW_TRACEPOINT_OPEN, &attr, attr_sz); return libbpf_err_errno(fd); } +int bpf_raw_tracepoint_open(const char *name, int prog_fd) +{ + LIBBPF_OPTS(bpf_raw_tp_opts, opts, .tp_name = name); + + return bpf_raw_tracepoint_open_opts(prog_fd, &opts); +} + int bpf_btf_load(const void *btf_data, size_t btf_size, struct bpf_btf_load_opts *opts) { const size_t attr_sz = offsetofend(union bpf_attr, btf_token_fd); diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h index df0db2f0cdb7..972e17ec0c09 100644 --- a/tools/lib/bpf/bpf.h +++ b/tools/lib/bpf/bpf.h @@ -617,6 +617,15 @@ LIBBPF_API int bpf_prog_query(int target_fd, enum bpf_attach_type type, __u32 query_flags, __u32 *attach_flags, __u32 *prog_ids, __u32 *prog_cnt); +struct bpf_raw_tp_opts { + size_t sz; /* size of this struct for forward/backward compatibility */ + const char *tp_name; + __u64 cookie; + size_t :0; +}; +#define bpf_raw_tp_opts__last_field cookie + +LIBBPF_API int bpf_raw_tracepoint_open_opts(int prog_fd, struct bpf_raw_tp_opts *opts); LIBBPF_API int bpf_raw_tracepoint_open(const char *name, int prog_fd); LIBBPF_API int bpf_task_fd_query(int pid, int fd, __u32 flags, char *buf, __u32 *buf_len, __u32 *prog_id, __u32 *fd_type, diff --git a/tools/lib/bpf/bpf_core_read.h b/tools/lib/bpf/bpf_core_read.h index 1ce738d91685..c0e13cdf9660 100644 --- a/tools/lib/bpf/bpf_core_read.h +++ b/tools/lib/bpf/bpf_core_read.h @@ -2,7 +2,7 @@ #ifndef __BPF_CORE_READ_H__ #define __BPF_CORE_READ_H__ -#include <bpf/bpf_helpers.h> +#include "bpf_helpers.h" /* * enum bpf_field_info_kind is passed as a second argument into @@ -104,6 +104,7 @@ enum bpf_enum_value_kind { case 2: val = *(const unsigned short *)p; break; \ case 4: val = *(const unsigned int *)p; break; \ case 8: val = *(const unsigned long long *)p; break; \ + default: val = 0; break; \ } \ val <<= __CORE_RELO(s, field, LSHIFT_U64); \ if (__CORE_RELO(s, field, SIGNED)) \ diff --git a/tools/lib/bpf/bpf_helpers.h b/tools/lib/bpf/bpf_helpers.h index cd17f6d0791f..305c62817dd3 100644 --- a/tools/lib/bpf/bpf_helpers.h +++ b/tools/lib/bpf/bpf_helpers.h @@ -137,7 +137,8 @@ /* * Helper function to perform a tail call with a constant/immediate map slot. */ -#if __clang_major__ >= 8 && defined(__bpf__) +#if (defined(__clang__) && __clang_major__ >= 8) || (!defined(__clang__) && __GNUC__ > 12) +#if defined(__bpf__) static __always_inline void bpf_tail_call_static(void *ctx, const void *map, const __u32 slot) { @@ -165,6 +166,7 @@ bpf_tail_call_static(void *ctx, const void *map, const __u32 slot) : "r0", "r1", "r2", "r3", "r4", "r5"); } #endif +#endif enum libbpf_pin_type { LIBBPF_PIN_NONE, @@ -184,10 +186,21 @@ enum libbpf_tristate { #define __kptr __attribute__((btf_type_tag("kptr"))) #define __percpu_kptr __attribute__((btf_type_tag("percpu_kptr"))) -#define bpf_ksym_exists(sym) ({ \ - _Static_assert(!__builtin_constant_p(!!sym), #sym " should be marked as __weak"); \ - !!sym; \ +#if defined (__clang__) +#define bpf_ksym_exists(sym) ({ \ + _Static_assert(!__builtin_constant_p(!!sym), \ + #sym " should be marked as __weak"); \ + !!sym; \ +}) +#elif __GNUC__ > 8 +#define bpf_ksym_exists(sym) ({ \ + _Static_assert(__builtin_has_attribute (*sym, __weak__), \ + #sym " should be marked as __weak"); \ + !!sym; \ }) +#else +#define bpf_ksym_exists(sym) !!sym +#endif #define __arg_ctx __attribute__((btf_decl_tag("arg:ctx"))) #define __arg_nonnull __attribute((btf_decl_tag("arg:nonnull"))) diff --git a/tools/lib/bpf/bpf_tracing.h b/tools/lib/bpf/bpf_tracing.h index 1c13f8e88833..9314fa95f04e 100644 --- a/tools/lib/bpf/bpf_tracing.h +++ b/tools/lib/bpf/bpf_tracing.h @@ -633,18 +633,18 @@ struct pt_regs; #endif #define ___bpf_ctx_cast0() ctx -#define ___bpf_ctx_cast1(x) ___bpf_ctx_cast0(), (void *)ctx[0] -#define ___bpf_ctx_cast2(x, args...) ___bpf_ctx_cast1(args), (void *)ctx[1] -#define ___bpf_ctx_cast3(x, args...) ___bpf_ctx_cast2(args), (void *)ctx[2] -#define ___bpf_ctx_cast4(x, args...) ___bpf_ctx_cast3(args), (void *)ctx[3] -#define ___bpf_ctx_cast5(x, args...) ___bpf_ctx_cast4(args), (void *)ctx[4] -#define ___bpf_ctx_cast6(x, args...) ___bpf_ctx_cast5(args), (void *)ctx[5] -#define ___bpf_ctx_cast7(x, args...) ___bpf_ctx_cast6(args), (void *)ctx[6] -#define ___bpf_ctx_cast8(x, args...) ___bpf_ctx_cast7(args), (void *)ctx[7] -#define ___bpf_ctx_cast9(x, args...) ___bpf_ctx_cast8(args), (void *)ctx[8] -#define ___bpf_ctx_cast10(x, args...) ___bpf_ctx_cast9(args), (void *)ctx[9] -#define ___bpf_ctx_cast11(x, args...) ___bpf_ctx_cast10(args), (void *)ctx[10] -#define ___bpf_ctx_cast12(x, args...) ___bpf_ctx_cast11(args), (void *)ctx[11] +#define ___bpf_ctx_cast1(x) ___bpf_ctx_cast0(), ctx[0] +#define ___bpf_ctx_cast2(x, args...) ___bpf_ctx_cast1(args), ctx[1] +#define ___bpf_ctx_cast3(x, args...) ___bpf_ctx_cast2(args), ctx[2] +#define ___bpf_ctx_cast4(x, args...) ___bpf_ctx_cast3(args), ctx[3] +#define ___bpf_ctx_cast5(x, args...) ___bpf_ctx_cast4(args), ctx[4] +#define ___bpf_ctx_cast6(x, args...) ___bpf_ctx_cast5(args), ctx[5] +#define ___bpf_ctx_cast7(x, args...) ___bpf_ctx_cast6(args), ctx[6] +#define ___bpf_ctx_cast8(x, args...) ___bpf_ctx_cast7(args), ctx[7] +#define ___bpf_ctx_cast9(x, args...) ___bpf_ctx_cast8(args), ctx[8] +#define ___bpf_ctx_cast10(x, args...) ___bpf_ctx_cast9(args), ctx[9] +#define ___bpf_ctx_cast11(x, args...) ___bpf_ctx_cast10(args), ctx[10] +#define ___bpf_ctx_cast12(x, args...) ___bpf_ctx_cast11(args), ctx[11] #define ___bpf_ctx_cast(args...) ___bpf_apply(___bpf_ctx_cast, ___bpf_narg(args))(args) /* @@ -786,14 +786,14 @@ ____##name(unsigned long long *ctx ___bpf_ctx_decl(args)) struct pt_regs; #define ___bpf_kprobe_args0() ctx -#define ___bpf_kprobe_args1(x) ___bpf_kprobe_args0(), (void *)PT_REGS_PARM1(ctx) -#define ___bpf_kprobe_args2(x, args...) ___bpf_kprobe_args1(args), (void *)PT_REGS_PARM2(ctx) -#define ___bpf_kprobe_args3(x, args...) ___bpf_kprobe_args2(args), (void *)PT_REGS_PARM3(ctx) -#define ___bpf_kprobe_args4(x, args...) ___bpf_kprobe_args3(args), (void *)PT_REGS_PARM4(ctx) -#define ___bpf_kprobe_args5(x, args...) ___bpf_kprobe_args4(args), (void *)PT_REGS_PARM5(ctx) -#define ___bpf_kprobe_args6(x, args...) ___bpf_kprobe_args5(args), (void *)PT_REGS_PARM6(ctx) -#define ___bpf_kprobe_args7(x, args...) ___bpf_kprobe_args6(args), (void *)PT_REGS_PARM7(ctx) -#define ___bpf_kprobe_args8(x, args...) ___bpf_kprobe_args7(args), (void *)PT_REGS_PARM8(ctx) +#define ___bpf_kprobe_args1(x) ___bpf_kprobe_args0(), (unsigned long long)PT_REGS_PARM1(ctx) +#define ___bpf_kprobe_args2(x, args...) ___bpf_kprobe_args1(args), (unsigned long long)PT_REGS_PARM2(ctx) +#define ___bpf_kprobe_args3(x, args...) ___bpf_kprobe_args2(args), (unsigned long long)PT_REGS_PARM3(ctx) +#define ___bpf_kprobe_args4(x, args...) ___bpf_kprobe_args3(args), (unsigned long long)PT_REGS_PARM4(ctx) +#define ___bpf_kprobe_args5(x, args...) ___bpf_kprobe_args4(args), (unsigned long long)PT_REGS_PARM5(ctx) +#define ___bpf_kprobe_args6(x, args...) ___bpf_kprobe_args5(args), (unsigned long long)PT_REGS_PARM6(ctx) +#define ___bpf_kprobe_args7(x, args...) ___bpf_kprobe_args6(args), (unsigned long long)PT_REGS_PARM7(ctx) +#define ___bpf_kprobe_args8(x, args...) ___bpf_kprobe_args7(args), (unsigned long long)PT_REGS_PARM8(ctx) #define ___bpf_kprobe_args(args...) ___bpf_apply(___bpf_kprobe_args, ___bpf_narg(args))(args) /* @@ -821,7 +821,7 @@ static __always_inline typeof(name(0)) \ ____##name(struct pt_regs *ctx, ##args) #define ___bpf_kretprobe_args0() ctx -#define ___bpf_kretprobe_args1(x) ___bpf_kretprobe_args0(), (void *)PT_REGS_RC(ctx) +#define ___bpf_kretprobe_args1(x) ___bpf_kretprobe_args0(), (unsigned long long)PT_REGS_RC(ctx) #define ___bpf_kretprobe_args(args...) ___bpf_apply(___bpf_kretprobe_args, ___bpf_narg(args))(args) /* @@ -845,24 +845,24 @@ static __always_inline typeof(name(0)) ____##name(struct pt_regs *ctx, ##args) /* If kernel has CONFIG_ARCH_HAS_SYSCALL_WRAPPER, read pt_regs directly */ #define ___bpf_syscall_args0() ctx -#define ___bpf_syscall_args1(x) ___bpf_syscall_args0(), (void *)PT_REGS_PARM1_SYSCALL(regs) -#define ___bpf_syscall_args2(x, args...) ___bpf_syscall_args1(args), (void *)PT_REGS_PARM2_SYSCALL(regs) -#define ___bpf_syscall_args3(x, args...) ___bpf_syscall_args2(args), (void *)PT_REGS_PARM3_SYSCALL(regs) -#define ___bpf_syscall_args4(x, args...) ___bpf_syscall_args3(args), (void *)PT_REGS_PARM4_SYSCALL(regs) -#define ___bpf_syscall_args5(x, args...) ___bpf_syscall_args4(args), (void *)PT_REGS_PARM5_SYSCALL(regs) -#define ___bpf_syscall_args6(x, args...) ___bpf_syscall_args5(args), (void *)PT_REGS_PARM6_SYSCALL(regs) -#define ___bpf_syscall_args7(x, args...) ___bpf_syscall_args6(args), (void *)PT_REGS_PARM7_SYSCALL(regs) +#define ___bpf_syscall_args1(x) ___bpf_syscall_args0(), (unsigned long long)PT_REGS_PARM1_SYSCALL(regs) +#define ___bpf_syscall_args2(x, args...) ___bpf_syscall_args1(args), (unsigned long long)PT_REGS_PARM2_SYSCALL(regs) +#define ___bpf_syscall_args3(x, args...) ___bpf_syscall_args2(args), (unsigned long long)PT_REGS_PARM3_SYSCALL(regs) +#define ___bpf_syscall_args4(x, args...) ___bpf_syscall_args3(args), (unsigned long long)PT_REGS_PARM4_SYSCALL(regs) +#define ___bpf_syscall_args5(x, args...) ___bpf_syscall_args4(args), (unsigned long long)PT_REGS_PARM5_SYSCALL(regs) +#define ___bpf_syscall_args6(x, args...) ___bpf_syscall_args5(args), (unsigned long long)PT_REGS_PARM6_SYSCALL(regs) +#define ___bpf_syscall_args7(x, args...) ___bpf_syscall_args6(args), (unsigned long long)PT_REGS_PARM7_SYSCALL(regs) #define ___bpf_syscall_args(args...) ___bpf_apply(___bpf_syscall_args, ___bpf_narg(args))(args) /* If kernel doesn't have CONFIG_ARCH_HAS_SYSCALL_WRAPPER, we have to BPF_CORE_READ from pt_regs */ #define ___bpf_syswrap_args0() ctx -#define ___bpf_syswrap_args1(x) ___bpf_syswrap_args0(), (void *)PT_REGS_PARM1_CORE_SYSCALL(regs) -#define ___bpf_syswrap_args2(x, args...) ___bpf_syswrap_args1(args), (void *)PT_REGS_PARM2_CORE_SYSCALL(regs) -#define ___bpf_syswrap_args3(x, args...) ___bpf_syswrap_args2(args), (void *)PT_REGS_PARM3_CORE_SYSCALL(regs) -#define ___bpf_syswrap_args4(x, args...) ___bpf_syswrap_args3(args), (void *)PT_REGS_PARM4_CORE_SYSCALL(regs) -#define ___bpf_syswrap_args5(x, args...) ___bpf_syswrap_args4(args), (void *)PT_REGS_PARM5_CORE_SYSCALL(regs) -#define ___bpf_syswrap_args6(x, args...) ___bpf_syswrap_args5(args), (void *)PT_REGS_PARM6_CORE_SYSCALL(regs) -#define ___bpf_syswrap_args7(x, args...) ___bpf_syswrap_args6(args), (void *)PT_REGS_PARM7_CORE_SYSCALL(regs) +#define ___bpf_syswrap_args1(x) ___bpf_syswrap_args0(), (unsigned long long)PT_REGS_PARM1_CORE_SYSCALL(regs) +#define ___bpf_syswrap_args2(x, args...) ___bpf_syswrap_args1(args), (unsigned long long)PT_REGS_PARM2_CORE_SYSCALL(regs) +#define ___bpf_syswrap_args3(x, args...) ___bpf_syswrap_args2(args), (unsigned long long)PT_REGS_PARM3_CORE_SYSCALL(regs) +#define ___bpf_syswrap_args4(x, args...) ___bpf_syswrap_args3(args), (unsigned long long)PT_REGS_PARM4_CORE_SYSCALL(regs) +#define ___bpf_syswrap_args5(x, args...) ___bpf_syswrap_args4(args), (unsigned long long)PT_REGS_PARM5_CORE_SYSCALL(regs) +#define ___bpf_syswrap_args6(x, args...) ___bpf_syswrap_args5(args), (unsigned long long)PT_REGS_PARM6_CORE_SYSCALL(regs) +#define ___bpf_syswrap_args7(x, args...) ___bpf_syswrap_args6(args), (unsigned long long)PT_REGS_PARM7_CORE_SYSCALL(regs) #define ___bpf_syswrap_args(args...) ___bpf_apply(___bpf_syswrap_args, ___bpf_narg(args))(args) /* diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c index 2d0840ef599a..32c00db3b91b 100644 --- a/tools/lib/bpf/btf.c +++ b/tools/lib/bpf/btf.c @@ -116,6 +116,9 @@ struct btf { /* whether strings are already deduplicated */ bool strs_deduped; + /* whether base_btf should be freed in btf_free for this instance */ + bool owns_base; + /* BTF object FD, if loaded into kernel */ int fd; @@ -598,7 +601,7 @@ static int btf_sanity_check(const struct btf *btf) __u32 i, n = btf__type_cnt(btf); int err; - for (i = 1; i < n; i++) { + for (i = btf->start_id; i < n; i++) { t = btf_type_by_id(btf, i); err = btf_validate_type(btf, t, i); if (err) @@ -969,6 +972,8 @@ void btf__free(struct btf *btf) free(btf->raw_data); free(btf->raw_data_swapped); free(btf->type_offs); + if (btf->owns_base) + btf__free(btf->base_btf); free(btf); } @@ -1084,53 +1089,38 @@ struct btf *btf__new_split(const void *data, __u32 size, struct btf *base_btf) return libbpf_ptr(btf_new(data, size, base_btf)); } -static struct btf *btf_parse_elf(const char *path, struct btf *base_btf, - struct btf_ext **btf_ext) +struct btf_elf_secs { + Elf_Data *btf_data; + Elf_Data *btf_ext_data; + Elf_Data *btf_base_data; +}; + +static int btf_find_elf_sections(Elf *elf, const char *path, struct btf_elf_secs *secs) { - Elf_Data *btf_data = NULL, *btf_ext_data = NULL; - int err = 0, fd = -1, idx = 0; - struct btf *btf = NULL; Elf_Scn *scn = NULL; - Elf *elf = NULL; + Elf_Data *data; GElf_Ehdr ehdr; size_t shstrndx; + int idx = 0; - if (elf_version(EV_CURRENT) == EV_NONE) { - pr_warn("failed to init libelf for %s\n", path); - return ERR_PTR(-LIBBPF_ERRNO__LIBELF); - } - - fd = open(path, O_RDONLY | O_CLOEXEC); - if (fd < 0) { - err = -errno; - pr_warn("failed to open %s: %s\n", path, strerror(errno)); - return ERR_PTR(err); - } - - err = -LIBBPF_ERRNO__FORMAT; - - elf = elf_begin(fd, ELF_C_READ, NULL); - if (!elf) { - pr_warn("failed to open %s as ELF file\n", path); - goto done; - } if (!gelf_getehdr(elf, &ehdr)) { pr_warn("failed to get EHDR from %s\n", path); - goto done; + goto err; } if (elf_getshdrstrndx(elf, &shstrndx)) { pr_warn("failed to get section names section index for %s\n", path); - goto done; + goto err; } if (!elf_rawdata(elf_getscn(elf, shstrndx), NULL)) { pr_warn("failed to get e_shstrndx from %s\n", path); - goto done; + goto err; } while ((scn = elf_nextscn(elf, scn)) != NULL) { + Elf_Data **field; GElf_Shdr sh; char *name; @@ -1138,42 +1128,102 @@ static struct btf *btf_parse_elf(const char *path, struct btf *base_btf, if (gelf_getshdr(scn, &sh) != &sh) { pr_warn("failed to get section(%d) header from %s\n", idx, path); - goto done; + goto err; } name = elf_strptr(elf, shstrndx, sh.sh_name); if (!name) { pr_warn("failed to get section(%d) name from %s\n", idx, path); - goto done; + goto err; } - if (strcmp(name, BTF_ELF_SEC) == 0) { - btf_data = elf_getdata(scn, 0); - if (!btf_data) { - pr_warn("failed to get section(%d, %s) data from %s\n", - idx, name, path); - goto done; - } - continue; - } else if (btf_ext && strcmp(name, BTF_EXT_ELF_SEC) == 0) { - btf_ext_data = elf_getdata(scn, 0); - if (!btf_ext_data) { - pr_warn("failed to get section(%d, %s) data from %s\n", - idx, name, path); - goto done; - } + + if (strcmp(name, BTF_ELF_SEC) == 0) + field = &secs->btf_data; + else if (strcmp(name, BTF_EXT_ELF_SEC) == 0) + field = &secs->btf_ext_data; + else if (strcmp(name, BTF_BASE_ELF_SEC) == 0) + field = &secs->btf_base_data; + else continue; + + data = elf_getdata(scn, 0); + if (!data) { + pr_warn("failed to get section(%d, %s) data from %s\n", + idx, name, path); + goto err; } + *field = data; } - if (!btf_data) { + return 0; + +err: + return -LIBBPF_ERRNO__FORMAT; +} + +static struct btf *btf_parse_elf(const char *path, struct btf *base_btf, + struct btf_ext **btf_ext) +{ + struct btf_elf_secs secs = {}; + struct btf *dist_base_btf = NULL; + struct btf *btf = NULL; + int err = 0, fd = -1; + Elf *elf = NULL; + + if (elf_version(EV_CURRENT) == EV_NONE) { + pr_warn("failed to init libelf for %s\n", path); + return ERR_PTR(-LIBBPF_ERRNO__LIBELF); + } + + fd = open(path, O_RDONLY | O_CLOEXEC); + if (fd < 0) { + err = -errno; + pr_warn("failed to open %s: %s\n", path, strerror(errno)); + return ERR_PTR(err); + } + + elf = elf_begin(fd, ELF_C_READ, NULL); + if (!elf) { + pr_warn("failed to open %s as ELF file\n", path); + goto done; + } + + err = btf_find_elf_sections(elf, path, &secs); + if (err) + goto done; + + if (!secs.btf_data) { pr_warn("failed to find '%s' ELF section in %s\n", BTF_ELF_SEC, path); err = -ENODATA; goto done; } - btf = btf_new(btf_data->d_buf, btf_data->d_size, base_btf); - err = libbpf_get_error(btf); - if (err) + + if (secs.btf_base_data) { + dist_base_btf = btf_new(secs.btf_base_data->d_buf, secs.btf_base_data->d_size, + NULL); + if (IS_ERR(dist_base_btf)) { + err = PTR_ERR(dist_base_btf); + dist_base_btf = NULL; + goto done; + } + } + + btf = btf_new(secs.btf_data->d_buf, secs.btf_data->d_size, + dist_base_btf ?: base_btf); + if (IS_ERR(btf)) { + err = PTR_ERR(btf); goto done; + } + if (dist_base_btf && base_btf) { + err = btf__relocate(btf, base_btf); + if (err) + goto done; + btf__free(dist_base_btf); + dist_base_btf = NULL; + } + + if (dist_base_btf) + btf->owns_base = true; switch (gelf_getclass(elf)) { case ELFCLASS32: @@ -1187,11 +1237,12 @@ static struct btf *btf_parse_elf(const char *path, struct btf *base_btf, break; } - if (btf_ext && btf_ext_data) { - *btf_ext = btf_ext__new(btf_ext_data->d_buf, btf_ext_data->d_size); - err = libbpf_get_error(*btf_ext); - if (err) + if (btf_ext && secs.btf_ext_data) { + *btf_ext = btf_ext__new(secs.btf_ext_data->d_buf, secs.btf_ext_data->d_size); + if (IS_ERR(*btf_ext)) { + err = PTR_ERR(*btf_ext); goto done; + } } else if (btf_ext) { *btf_ext = NULL; } @@ -1205,6 +1256,7 @@ done: if (btf_ext) btf_ext__free(*btf_ext); + btf__free(dist_base_btf); btf__free(btf); return ERR_PTR(err); @@ -1739,9 +1791,8 @@ struct btf_pipe { struct hashmap *str_off_map; /* map string offsets from src to dst */ }; -static int btf_rewrite_str(__u32 *str_off, void *ctx) +static int btf_rewrite_str(struct btf_pipe *p, __u32 *str_off) { - struct btf_pipe *p = ctx; long mapped_off; int off, err; @@ -1771,10 +1822,11 @@ static int btf_rewrite_str(__u32 *str_off, void *ctx) return 0; } -int btf__add_type(struct btf *btf, const struct btf *src_btf, const struct btf_type *src_type) +static int btf_add_type(struct btf_pipe *p, const struct btf_type *src_type) { - struct btf_pipe p = { .src = src_btf, .dst = btf }; + struct btf_field_iter it; struct btf_type *t; + __u32 *str_off; int sz, err; sz = btf_type_size(src_type); @@ -1782,35 +1834,33 @@ int btf__add_type(struct btf *btf, const struct btf *src_btf, const struct btf_t return libbpf_err(sz); /* deconstruct BTF, if necessary, and invalidate raw_data */ - if (btf_ensure_modifiable(btf)) + if (btf_ensure_modifiable(p->dst)) return libbpf_err(-ENOMEM); - t = btf_add_type_mem(btf, sz); + t = btf_add_type_mem(p->dst, sz); if (!t) return libbpf_err(-ENOMEM); memcpy(t, src_type, sz); - err = btf_type_visit_str_offs(t, btf_rewrite_str, &p); + err = btf_field_iter_init(&it, t, BTF_FIELD_ITER_STRS); if (err) return libbpf_err(err); - return btf_commit_type(btf, sz); + while ((str_off = btf_field_iter_next(&it))) { + err = btf_rewrite_str(p, str_off); + if (err) + return libbpf_err(err); + } + + return btf_commit_type(p->dst, sz); } -static int btf_rewrite_type_ids(__u32 *type_id, void *ctx) +int btf__add_type(struct btf *btf, const struct btf *src_btf, const struct btf_type *src_type) { - struct btf *btf = ctx; - - if (!*type_id) /* nothing to do for VOID references */ - return 0; + struct btf_pipe p = { .src = src_btf, .dst = btf }; - /* we haven't updated btf's type count yet, so - * btf->start_id + btf->nr_types - 1 is the type ID offset we should - * add to all newly added BTF types - */ - *type_id += btf->start_id + btf->nr_types - 1; - return 0; + return btf_add_type(&p, src_type); } static size_t btf_dedup_identity_hash_fn(long key, void *ctx); @@ -1858,6 +1908,9 @@ int btf__add_btf(struct btf *btf, const struct btf *src_btf) memcpy(t, src_btf->types_data, data_sz); for (i = 0; i < cnt; i++) { + struct btf_field_iter it; + __u32 *type_id, *str_off; + sz = btf_type_size(t); if (sz < 0) { /* unlikely, has to be corrupted src_btf */ @@ -1869,15 +1922,31 @@ int btf__add_btf(struct btf *btf, const struct btf *src_btf) *off = t - btf->types_data; /* add, dedup, and remap strings referenced by this BTF type */ - err = btf_type_visit_str_offs(t, btf_rewrite_str, &p); + err = btf_field_iter_init(&it, t, BTF_FIELD_ITER_STRS); if (err) goto err_out; + while ((str_off = btf_field_iter_next(&it))) { + err = btf_rewrite_str(&p, str_off); + if (err) + goto err_out; + } /* remap all type IDs referenced from this BTF type */ - err = btf_type_visit_type_ids(t, btf_rewrite_type_ids, btf); + err = btf_field_iter_init(&it, t, BTF_FIELD_ITER_IDS); if (err) goto err_out; + while ((type_id = btf_field_iter_next(&it))) { + if (!*type_id) /* nothing to do for VOID references */ + continue; + + /* we haven't updated btf's type count yet, so + * btf->start_id + btf->nr_types - 1 is the type ID offset we should + * add to all newly added BTF types + */ + *type_id += btf->start_id + btf->nr_types - 1; + } + /* go to next type data and type offset index entry */ t += sz; off++; @@ -3453,11 +3522,19 @@ static int btf_for_each_str_off(struct btf_dedup *d, str_off_visit_fn fn, void * int i, r; for (i = 0; i < d->btf->nr_types; i++) { + struct btf_field_iter it; struct btf_type *t = btf_type_by_id(d->btf, d->btf->start_id + i); + __u32 *str_off; - r = btf_type_visit_str_offs(t, fn, ctx); + r = btf_field_iter_init(&it, t, BTF_FIELD_ITER_STRS); if (r) return r; + + while ((str_off = btf_field_iter_next(&it))) { + r = fn(str_off, ctx); + if (r) + return r; + } } if (!d->btf_ext) @@ -4919,10 +4996,23 @@ static int btf_dedup_remap_types(struct btf_dedup *d) for (i = 0; i < d->btf->nr_types; i++) { struct btf_type *t = btf_type_by_id(d->btf, d->btf->start_id + i); + struct btf_field_iter it; + __u32 *type_id; - r = btf_type_visit_type_ids(t, btf_dedup_remap_type_id, d); + r = btf_field_iter_init(&it, t, BTF_FIELD_ITER_IDS); if (r) return r; + + while ((type_id = btf_field_iter_next(&it))) { + __u32 resolved_id, new_id; + + resolved_id = resolve_type_id(d, *type_id); + new_id = d->hypot_map[resolved_id]; + if (new_id > BTF_MAX_NR_TYPES) + return -EINVAL; + + *type_id = new_id; + } } if (!d->btf_ext) @@ -5003,136 +5093,6 @@ struct btf *btf__load_module_btf(const char *module_name, struct btf *vmlinux_bt return btf__parse_split(path, vmlinux_btf); } -int btf_type_visit_type_ids(struct btf_type *t, type_id_visit_fn visit, void *ctx) -{ - int i, n, err; - - switch (btf_kind(t)) { - case BTF_KIND_INT: - case BTF_KIND_FLOAT: - case BTF_KIND_ENUM: - case BTF_KIND_ENUM64: - return 0; - - case BTF_KIND_FWD: - case BTF_KIND_CONST: - case BTF_KIND_VOLATILE: - case BTF_KIND_RESTRICT: - case BTF_KIND_PTR: - case BTF_KIND_TYPEDEF: - case BTF_KIND_FUNC: - case BTF_KIND_VAR: - case BTF_KIND_DECL_TAG: - case BTF_KIND_TYPE_TAG: - return visit(&t->type, ctx); - - case BTF_KIND_ARRAY: { - struct btf_array *a = btf_array(t); - - err = visit(&a->type, ctx); - err = err ?: visit(&a->index_type, ctx); - return err; - } - - case BTF_KIND_STRUCT: - case BTF_KIND_UNION: { - struct btf_member *m = btf_members(t); - - for (i = 0, n = btf_vlen(t); i < n; i++, m++) { - err = visit(&m->type, ctx); - if (err) - return err; - } - return 0; - } - - case BTF_KIND_FUNC_PROTO: { - struct btf_param *m = btf_params(t); - - err = visit(&t->type, ctx); - if (err) - return err; - for (i = 0, n = btf_vlen(t); i < n; i++, m++) { - err = visit(&m->type, ctx); - if (err) - return err; - } - return 0; - } - - case BTF_KIND_DATASEC: { - struct btf_var_secinfo *m = btf_var_secinfos(t); - - for (i = 0, n = btf_vlen(t); i < n; i++, m++) { - err = visit(&m->type, ctx); - if (err) - return err; - } - return 0; - } - - default: - return -EINVAL; - } -} - -int btf_type_visit_str_offs(struct btf_type *t, str_off_visit_fn visit, void *ctx) -{ - int i, n, err; - - err = visit(&t->name_off, ctx); - if (err) - return err; - - switch (btf_kind(t)) { - case BTF_KIND_STRUCT: - case BTF_KIND_UNION: { - struct btf_member *m = btf_members(t); - - for (i = 0, n = btf_vlen(t); i < n; i++, m++) { - err = visit(&m->name_off, ctx); - if (err) - return err; - } - break; - } - case BTF_KIND_ENUM: { - struct btf_enum *m = btf_enum(t); - - for (i = 0, n = btf_vlen(t); i < n; i++, m++) { - err = visit(&m->name_off, ctx); - if (err) - return err; - } - break; - } - case BTF_KIND_ENUM64: { - struct btf_enum64 *m = btf_enum64(t); - - for (i = 0, n = btf_vlen(t); i < n; i++, m++) { - err = visit(&m->name_off, ctx); - if (err) - return err; - } - break; - } - case BTF_KIND_FUNC_PROTO: { - struct btf_param *m = btf_params(t); - - for (i = 0, n = btf_vlen(t); i < n; i++, m++) { - err = visit(&m->name_off, ctx); - if (err) - return err; - } - break; - } - default: - break; - } - - return 0; -} - int btf_ext_visit_type_ids(struct btf_ext *btf_ext, type_id_visit_fn visit, void *ctx) { const struct btf_ext_info *seg; @@ -5212,3 +5172,325 @@ int btf_ext_visit_str_offs(struct btf_ext *btf_ext, str_off_visit_fn visit, void return 0; } + +struct btf_distill { + struct btf_pipe pipe; + int *id_map; + unsigned int split_start_id; + unsigned int split_start_str; + int diff_id; +}; + +static int btf_add_distilled_type_ids(struct btf_distill *dist, __u32 i) +{ + struct btf_type *split_t = btf_type_by_id(dist->pipe.src, i); + struct btf_field_iter it; + __u32 *id; + int err; + + err = btf_field_iter_init(&it, split_t, BTF_FIELD_ITER_IDS); + if (err) + return err; + while ((id = btf_field_iter_next(&it))) { + struct btf_type *base_t; + + if (!*id) + continue; + /* split BTF id, not needed */ + if (*id >= dist->split_start_id) + continue; + /* already added ? */ + if (dist->id_map[*id] > 0) + continue; + + /* only a subset of base BTF types should be referenced from + * split BTF; ensure nothing unexpected is referenced. + */ + base_t = btf_type_by_id(dist->pipe.src, *id); + switch (btf_kind(base_t)) { + case BTF_KIND_INT: + case BTF_KIND_FLOAT: + case BTF_KIND_FWD: + case BTF_KIND_ARRAY: + case BTF_KIND_STRUCT: + case BTF_KIND_UNION: + case BTF_KIND_TYPEDEF: + case BTF_KIND_ENUM: + case BTF_KIND_ENUM64: + case BTF_KIND_PTR: + case BTF_KIND_CONST: + case BTF_KIND_RESTRICT: + case BTF_KIND_VOLATILE: + case BTF_KIND_FUNC_PROTO: + case BTF_KIND_TYPE_TAG: + dist->id_map[*id] = *id; + break; + default: + pr_warn("unexpected reference to base type[%u] of kind [%u] when creating distilled base BTF.\n", + *id, btf_kind(base_t)); + return -EINVAL; + } + /* If a base type is used, ensure types it refers to are + * marked as used also; so for example if we find a PTR to INT + * we need both the PTR and INT. + * + * The only exception is named struct/unions, since distilled + * base BTF composite types have no members. + */ + if (btf_is_composite(base_t) && base_t->name_off) + continue; + err = btf_add_distilled_type_ids(dist, *id); + if (err) + return err; + } + return 0; +} + +static int btf_add_distilled_types(struct btf_distill *dist) +{ + bool adding_to_base = dist->pipe.dst->start_id == 1; + int id = btf__type_cnt(dist->pipe.dst); + struct btf_type *t; + int i, err = 0; + + + /* Add types for each of the required references to either distilled + * base or split BTF, depending on type characteristics. + */ + for (i = 1; i < dist->split_start_id; i++) { + const char *name; + int kind; + + if (!dist->id_map[i]) + continue; + t = btf_type_by_id(dist->pipe.src, i); + kind = btf_kind(t); + name = btf__name_by_offset(dist->pipe.src, t->name_off); + + switch (kind) { + case BTF_KIND_INT: + case BTF_KIND_FLOAT: + case BTF_KIND_FWD: + /* Named int, float, fwd are added to base. */ + if (!adding_to_base) + continue; + err = btf_add_type(&dist->pipe, t); + break; + case BTF_KIND_STRUCT: + case BTF_KIND_UNION: + /* Named struct/union are added to base as 0-vlen + * struct/union of same size. Anonymous struct/unions + * are added to split BTF as-is. + */ + if (adding_to_base) { + if (!t->name_off) + continue; + err = btf_add_composite(dist->pipe.dst, kind, name, t->size); + } else { + if (t->name_off) + continue; + err = btf_add_type(&dist->pipe, t); + } + break; + case BTF_KIND_ENUM: + case BTF_KIND_ENUM64: + /* Named enum[64]s are added to base as a sized + * enum; relocation will match with appropriately-named + * and sized enum or enum64. + * + * Anonymous enums are added to split BTF as-is. + */ + if (adding_to_base) { + if (!t->name_off) + continue; + err = btf__add_enum(dist->pipe.dst, name, t->size); + } else { + if (t->name_off) + continue; + err = btf_add_type(&dist->pipe, t); + } + break; + case BTF_KIND_ARRAY: + case BTF_KIND_TYPEDEF: + case BTF_KIND_PTR: + case BTF_KIND_CONST: + case BTF_KIND_RESTRICT: + case BTF_KIND_VOLATILE: + case BTF_KIND_FUNC_PROTO: + case BTF_KIND_TYPE_TAG: + /* All other types are added to split BTF. */ + if (adding_to_base) + continue; + err = btf_add_type(&dist->pipe, t); + break; + default: + pr_warn("unexpected kind when adding base type '%s'[%u] of kind [%u] to distilled base BTF.\n", + name, i, kind); + return -EINVAL; + + } + if (err < 0) + break; + dist->id_map[i] = id++; + } + return err; +} + +/* Split BTF ids without a mapping will be shifted downwards since distilled + * base BTF is smaller than the original base BTF. For those that have a + * mapping (either to base or updated split BTF), update the id based on + * that mapping. + */ +static int btf_update_distilled_type_ids(struct btf_distill *dist, __u32 i) +{ + struct btf_type *t = btf_type_by_id(dist->pipe.dst, i); + struct btf_field_iter it; + __u32 *id; + int err; + + err = btf_field_iter_init(&it, t, BTF_FIELD_ITER_IDS); + if (err) + return err; + while ((id = btf_field_iter_next(&it))) { + if (dist->id_map[*id]) + *id = dist->id_map[*id]; + else if (*id >= dist->split_start_id) + *id -= dist->diff_id; + } + return 0; +} + +/* Create updated split BTF with distilled base BTF; distilled base BTF + * consists of BTF information required to clarify the types that split + * BTF refers to, omitting unneeded details. Specifically it will contain + * base types and memberless definitions of named structs, unions and enumerated + * types. Associated reference types like pointers, arrays and anonymous + * structs, unions and enumerated types will be added to split BTF. + * Size is recorded for named struct/unions to help guide matching to the + * target base BTF during later relocation. + * + * The only case where structs, unions or enumerated types are fully represented + * is when they are anonymous; in such cases, the anonymous type is added to + * split BTF in full. + * + * We return newly-created split BTF where the split BTF refers to a newly-created + * distilled base BTF. Both must be freed separately by the caller. + */ +int btf__distill_base(const struct btf *src_btf, struct btf **new_base_btf, + struct btf **new_split_btf) +{ + struct btf *new_base = NULL, *new_split = NULL; + const struct btf *old_base; + unsigned int n = btf__type_cnt(src_btf); + struct btf_distill dist = {}; + struct btf_type *t; + int i, err = 0; + + /* src BTF must be split BTF. */ + old_base = btf__base_btf(src_btf); + if (!new_base_btf || !new_split_btf || !old_base) + return libbpf_err(-EINVAL); + + new_base = btf__new_empty(); + if (!new_base) + return libbpf_err(-ENOMEM); + dist.id_map = calloc(n, sizeof(*dist.id_map)); + if (!dist.id_map) { + err = -ENOMEM; + goto done; + } + dist.pipe.src = src_btf; + dist.pipe.dst = new_base; + dist.pipe.str_off_map = hashmap__new(btf_dedup_identity_hash_fn, btf_dedup_equal_fn, NULL); + if (IS_ERR(dist.pipe.str_off_map)) { + err = -ENOMEM; + goto done; + } + dist.split_start_id = btf__type_cnt(old_base); + dist.split_start_str = old_base->hdr->str_len; + + /* Pass over src split BTF; generate the list of base BTF type ids it + * references; these will constitute our distilled BTF set to be + * distributed over base and split BTF as appropriate. + */ + for (i = src_btf->start_id; i < n; i++) { + err = btf_add_distilled_type_ids(&dist, i); + if (err < 0) + goto done; + } + /* Next add types for each of the required references to base BTF and split BTF + * in turn. + */ + err = btf_add_distilled_types(&dist); + if (err < 0) + goto done; + + /* Create new split BTF with distilled base BTF as its base; the final + * state is split BTF with distilled base BTF that represents enough + * about its base references to allow it to be relocated with the base + * BTF available. + */ + new_split = btf__new_empty_split(new_base); + if (!new_split) { + err = -errno; + goto done; + } + dist.pipe.dst = new_split; + /* First add all split types */ + for (i = src_btf->start_id; i < n; i++) { + t = btf_type_by_id(src_btf, i); + err = btf_add_type(&dist.pipe, t); + if (err < 0) + goto done; + } + /* Now add distilled types to split BTF that are not added to base. */ + err = btf_add_distilled_types(&dist); + if (err < 0) + goto done; + + /* All split BTF ids will be shifted downwards since there are less base + * BTF ids in distilled base BTF. + */ + dist.diff_id = dist.split_start_id - btf__type_cnt(new_base); + + n = btf__type_cnt(new_split); + /* Now update base/split BTF ids. */ + for (i = 1; i < n; i++) { + err = btf_update_distilled_type_ids(&dist, i); + if (err < 0) + break; + } +done: + free(dist.id_map); + hashmap__free(dist.pipe.str_off_map); + if (err) { + btf__free(new_split); + btf__free(new_base); + return libbpf_err(err); + } + *new_base_btf = new_base; + *new_split_btf = new_split; + + return 0; +} + +const struct btf_header *btf_header(const struct btf *btf) +{ + return btf->hdr; +} + +void btf_set_base_btf(struct btf *btf, const struct btf *base_btf) +{ + btf->base_btf = (struct btf *)base_btf; + btf->start_id = btf__type_cnt(base_btf); + btf->start_str_off = base_btf->hdr->str_len; +} + +int btf__relocate(struct btf *btf, const struct btf *base_btf) +{ + int err = btf_relocate(btf, base_btf, NULL); + + if (!err) + btf->owns_base = false; + return libbpf_err(err); +} diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h index 8e6880d91c84..b68d216837a9 100644 --- a/tools/lib/bpf/btf.h +++ b/tools/lib/bpf/btf.h @@ -18,6 +18,7 @@ extern "C" { #define BTF_ELF_SEC ".BTF" #define BTF_EXT_ELF_SEC ".BTF.ext" +#define BTF_BASE_ELF_SEC ".BTF.base" #define MAPS_ELF_SEC ".maps" struct btf; @@ -107,6 +108,27 @@ LIBBPF_API struct btf *btf__new_empty(void); */ LIBBPF_API struct btf *btf__new_empty_split(struct btf *base_btf); +/** + * @brief **btf__distill_base()** creates new versions of the split BTF + * *src_btf* and its base BTF. The new base BTF will only contain the types + * needed to improve robustness of the split BTF to small changes in base BTF. + * When that split BTF is loaded against a (possibly changed) base, this + * distilled base BTF will help update references to that (possibly changed) + * base BTF. + * + * Both the new split and its associated new base BTF must be freed by + * the caller. + * + * If successful, 0 is returned and **new_base_btf** and **new_split_btf** + * will point at new base/split BTF. Both the new split and its associated + * new base BTF must be freed by the caller. + * + * A negative value is returned on error and the thread-local `errno` variable + * is set to the error code as well. + */ +LIBBPF_API int btf__distill_base(const struct btf *src_btf, struct btf **new_base_btf, + struct btf **new_split_btf); + LIBBPF_API struct btf *btf__parse(const char *path, struct btf_ext **btf_ext); LIBBPF_API struct btf *btf__parse_split(const char *path, struct btf *base_btf); LIBBPF_API struct btf *btf__parse_elf(const char *path, struct btf_ext **btf_ext); @@ -231,6 +253,20 @@ struct btf_dedup_opts { LIBBPF_API int btf__dedup(struct btf *btf, const struct btf_dedup_opts *opts); +/** + * @brief **btf__relocate()** will check the split BTF *btf* for references + * to base BTF kinds, and verify those references are compatible with + * *base_btf*; if they are, *btf* is adjusted such that is re-parented to + * *base_btf* and type ids and strings are adjusted to accommodate this. + * + * If successful, 0 is returned and **btf** now has **base_btf** as its + * base. + * + * A negative value is returned on error and the thread-local `errno` variable + * is set to the error code as well. + */ +LIBBPF_API int btf__relocate(struct btf *btf, const struct btf *base_btf); + struct btf_dump; struct btf_dump_opts { diff --git a/tools/lib/bpf/btf_dump.c b/tools/lib/bpf/btf_dump.c index 4d9f30bf7f01..894860111ddb 100644 --- a/tools/lib/bpf/btf_dump.c +++ b/tools/lib/bpf/btf_dump.c @@ -1559,10 +1559,12 @@ static void btf_dump_emit_type_chain(struct btf_dump *d, * Clang for BPF target generates func_proto with no * args as a func_proto with a single void arg (e.g., * `int (*f)(void)` vs just `int (*f)()`). We are - * going to pretend there are no args for such case. + * going to emit valid empty args (void) syntax for + * such case. Similarly and conveniently, valid + * no args case can be special-cased here as well. */ - if (vlen == 1 && p->type == 0) { - btf_dump_printf(d, ")"); + if (vlen == 0 || (vlen == 1 && p->type == 0)) { + btf_dump_printf(d, "void)"); return; } @@ -1929,6 +1931,7 @@ static int btf_dump_int_data(struct btf_dump *d, if (d->typed_dump->is_array_terminated) break; if (*(char *)data == '\0') { + btf_dump_type_values(d, "'\\0'"); d->typed_dump->is_array_terminated = true; break; } @@ -2031,6 +2034,7 @@ static int btf_dump_array_data(struct btf_dump *d, __u32 i, elem_type_id; __s64 elem_size; bool is_array_member; + bool is_array_terminated; elem_type_id = array->type; elem_type = skip_mods_and_typedefs(d->btf, elem_type_id, NULL); @@ -2066,12 +2070,15 @@ static int btf_dump_array_data(struct btf_dump *d, */ is_array_member = d->typed_dump->is_array_member; d->typed_dump->is_array_member = true; + is_array_terminated = d->typed_dump->is_array_terminated; + d->typed_dump->is_array_terminated = false; for (i = 0; i < array->nelems; i++, data += elem_size) { if (d->typed_dump->is_array_terminated) break; btf_dump_dump_type_data(d, NULL, elem_type, elem_type_id, data, 0, 0); } d->typed_dump->is_array_member = is_array_member; + d->typed_dump->is_array_terminated = is_array_terminated; d->typed_dump->depth--; btf_dump_data_pfx(d); btf_dump_type_values(d, "]"); diff --git a/tools/lib/bpf/btf_iter.c b/tools/lib/bpf/btf_iter.c new file mode 100644 index 000000000000..9a6c822c2294 --- /dev/null +++ b/tools/lib/bpf/btf_iter.c @@ -0,0 +1,177 @@ +// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) +/* Copyright (c) 2021 Facebook */ +/* Copyright (c) 2024, Oracle and/or its affiliates. */ + +#ifdef __KERNEL__ +#include <linux/bpf.h> +#include <linux/btf.h> + +#define btf_var_secinfos(t) (struct btf_var_secinfo *)btf_type_var_secinfo(t) + +#else +#include "btf.h" +#include "libbpf_internal.h" +#endif + +int btf_field_iter_init(struct btf_field_iter *it, struct btf_type *t, + enum btf_field_iter_kind iter_kind) +{ + it->p = NULL; + it->m_idx = -1; + it->off_idx = 0; + it->vlen = 0; + + switch (iter_kind) { + case BTF_FIELD_ITER_IDS: + switch (btf_kind(t)) { + case BTF_KIND_UNKN: + case BTF_KIND_INT: + case BTF_KIND_FLOAT: + case BTF_KIND_ENUM: + case BTF_KIND_ENUM64: + it->desc = (struct btf_field_desc) {}; + break; + case BTF_KIND_FWD: + case BTF_KIND_CONST: + case BTF_KIND_VOLATILE: + case BTF_KIND_RESTRICT: + case BTF_KIND_PTR: + case BTF_KIND_TYPEDEF: + case BTF_KIND_FUNC: + case BTF_KIND_VAR: + case BTF_KIND_DECL_TAG: + case BTF_KIND_TYPE_TAG: + it->desc = (struct btf_field_desc) { 1, {offsetof(struct btf_type, type)} }; + break; + case BTF_KIND_ARRAY: + it->desc = (struct btf_field_desc) { + 2, {sizeof(struct btf_type) + offsetof(struct btf_array, type), + sizeof(struct btf_type) + offsetof(struct btf_array, index_type)} + }; + break; + case BTF_KIND_STRUCT: + case BTF_KIND_UNION: + it->desc = (struct btf_field_desc) { + 0, {}, + sizeof(struct btf_member), + 1, {offsetof(struct btf_member, type)} + }; + break; + case BTF_KIND_FUNC_PROTO: + it->desc = (struct btf_field_desc) { + 1, {offsetof(struct btf_type, type)}, + sizeof(struct btf_param), + 1, {offsetof(struct btf_param, type)} + }; + break; + case BTF_KIND_DATASEC: + it->desc = (struct btf_field_desc) { + 0, {}, + sizeof(struct btf_var_secinfo), + 1, {offsetof(struct btf_var_secinfo, type)} + }; + break; + default: + return -EINVAL; + } + break; + case BTF_FIELD_ITER_STRS: + switch (btf_kind(t)) { + case BTF_KIND_UNKN: + it->desc = (struct btf_field_desc) {}; + break; + case BTF_KIND_INT: + case BTF_KIND_FLOAT: + case BTF_KIND_FWD: + case BTF_KIND_ARRAY: + case BTF_KIND_CONST: + case BTF_KIND_VOLATILE: + case BTF_KIND_RESTRICT: + case BTF_KIND_PTR: + case BTF_KIND_TYPEDEF: + case BTF_KIND_FUNC: + case BTF_KIND_VAR: + case BTF_KIND_DECL_TAG: + case BTF_KIND_TYPE_TAG: + case BTF_KIND_DATASEC: + it->desc = (struct btf_field_desc) { + 1, {offsetof(struct btf_type, name_off)} + }; + break; + case BTF_KIND_ENUM: + it->desc = (struct btf_field_desc) { + 1, {offsetof(struct btf_type, name_off)}, + sizeof(struct btf_enum), + 1, {offsetof(struct btf_enum, name_off)} + }; + break; + case BTF_KIND_ENUM64: + it->desc = (struct btf_field_desc) { + 1, {offsetof(struct btf_type, name_off)}, + sizeof(struct btf_enum64), + 1, {offsetof(struct btf_enum64, name_off)} + }; + break; + case BTF_KIND_STRUCT: + case BTF_KIND_UNION: + it->desc = (struct btf_field_desc) { + 1, {offsetof(struct btf_type, name_off)}, + sizeof(struct btf_member), + 1, {offsetof(struct btf_member, name_off)} + }; + break; + case BTF_KIND_FUNC_PROTO: + it->desc = (struct btf_field_desc) { + 1, {offsetof(struct btf_type, name_off)}, + sizeof(struct btf_param), + 1, {offsetof(struct btf_param, name_off)} + }; + break; + default: + return -EINVAL; + } + break; + default: + return -EINVAL; + } + + if (it->desc.m_sz) + it->vlen = btf_vlen(t); + + it->p = t; + return 0; +} + +__u32 *btf_field_iter_next(struct btf_field_iter *it) +{ + if (!it->p) + return NULL; + + if (it->m_idx < 0) { + if (it->off_idx < it->desc.t_off_cnt) + return it->p + it->desc.t_offs[it->off_idx++]; + /* move to per-member iteration */ + it->m_idx = 0; + it->p += sizeof(struct btf_type); + it->off_idx = 0; + } + + /* if type doesn't have members, stop */ + if (it->desc.m_sz == 0) { + it->p = NULL; + return NULL; + } + + if (it->off_idx >= it->desc.m_off_cnt) { + /* exhausted this member's fields, go to the next member */ + it->m_idx++; + it->p += it->desc.m_sz; + it->off_idx = 0; + } + + if (it->m_idx < it->vlen) + return it->p + it->desc.m_offs[it->off_idx++]; + + it->p = NULL; + return NULL; +} diff --git a/tools/lib/bpf/btf_relocate.c b/tools/lib/bpf/btf_relocate.c new file mode 100644 index 000000000000..17f8b32f94a0 --- /dev/null +++ b/tools/lib/bpf/btf_relocate.c @@ -0,0 +1,519 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2024, Oracle and/or its affiliates. */ + +#ifndef _GNU_SOURCE +#define _GNU_SOURCE +#endif + +#ifdef __KERNEL__ +#include <linux/bpf.h> +#include <linux/bsearch.h> +#include <linux/btf.h> +#include <linux/sort.h> +#include <linux/string.h> +#include <linux/bpf_verifier.h> + +#define btf_type_by_id (struct btf_type *)btf_type_by_id +#define btf__type_cnt btf_nr_types +#define btf__base_btf btf_base_btf +#define btf__name_by_offset btf_name_by_offset +#define btf__str_by_offset btf_str_by_offset +#define btf_kflag btf_type_kflag + +#define calloc(nmemb, sz) kvcalloc(nmemb, sz, GFP_KERNEL | __GFP_NOWARN) +#define free(ptr) kvfree(ptr) +#define qsort(base, num, sz, cmp) sort(base, num, sz, cmp, NULL) + +#else + +#include "btf.h" +#include "bpf.h" +#include "libbpf.h" +#include "libbpf_internal.h" + +#endif /* __KERNEL__ */ + +struct btf; + +struct btf_relocate { + struct btf *btf; + const struct btf *base_btf; + const struct btf *dist_base_btf; + unsigned int nr_base_types; + unsigned int nr_split_types; + unsigned int nr_dist_base_types; + int dist_str_len; + int base_str_len; + __u32 *id_map; + __u32 *str_map; +}; + +/* Set temporarily in relocation id_map if distilled base struct/union is + * embedded in a split BTF struct/union; in such a case, size information must + * match between distilled base BTF and base BTF representation of type. + */ +#define BTF_IS_EMBEDDED ((__u32)-1) + +/* <name, size, id> triple used in sorting/searching distilled base BTF. */ +struct btf_name_info { + const char *name; + /* set when search requires a size match */ + bool needs_size: 1; + unsigned int size: 31; + __u32 id; +}; + +static int btf_relocate_rewrite_type_id(struct btf_relocate *r, __u32 i) +{ + struct btf_type *t = btf_type_by_id(r->btf, i); + struct btf_field_iter it; + __u32 *id; + int err; + + err = btf_field_iter_init(&it, t, BTF_FIELD_ITER_IDS); + if (err) + return err; + + while ((id = btf_field_iter_next(&it))) + *id = r->id_map[*id]; + return 0; +} + +/* Simple string comparison used for sorting within BTF, since all distilled + * types are named. If strings match, and size is non-zero for both elements + * fall back to using size for ordering. + */ +static int cmp_btf_name_size(const void *n1, const void *n2) +{ + const struct btf_name_info *ni1 = n1; + const struct btf_name_info *ni2 = n2; + int name_diff = strcmp(ni1->name, ni2->name); + + if (!name_diff && ni1->needs_size && ni2->needs_size) + return ni2->size - ni1->size; + return name_diff; +} + +/* Binary search with a small twist; find leftmost element that matches + * so that we can then iterate through all exact matches. So for example + * searching { "a", "bb", "bb", "c" } we would always match on the + * leftmost "bb". + */ +static struct btf_name_info *search_btf_name_size(struct btf_name_info *key, + struct btf_name_info *vals, + int nelems) +{ + struct btf_name_info *ret = NULL; + int high = nelems - 1; + int low = 0; + + while (low <= high) { + int mid = (low + high)/2; + struct btf_name_info *val = &vals[mid]; + int diff = cmp_btf_name_size(key, val); + + if (diff == 0) + ret = val; + /* even if found, keep searching for leftmost match */ + if (diff <= 0) + high = mid - 1; + else + low = mid + 1; + } + return ret; +} + +/* If a member of a split BTF struct/union refers to a base BTF + * struct/union, mark that struct/union id temporarily in the id_map + * with BTF_IS_EMBEDDED. Members can be const/restrict/volatile/typedef + * reference types, but if a pointer is encountered, the type is no longer + * considered embedded. + */ +static int btf_mark_embedded_composite_type_ids(struct btf_relocate *r, __u32 i) +{ + struct btf_type *t = btf_type_by_id(r->btf, i); + struct btf_field_iter it; + __u32 *id; + int err; + + if (!btf_is_composite(t)) + return 0; + + err = btf_field_iter_init(&it, t, BTF_FIELD_ITER_IDS); + if (err) + return err; + + while ((id = btf_field_iter_next(&it))) { + __u32 next_id = *id; + + while (next_id) { + t = btf_type_by_id(r->btf, next_id); + switch (btf_kind(t)) { + case BTF_KIND_CONST: + case BTF_KIND_RESTRICT: + case BTF_KIND_VOLATILE: + case BTF_KIND_TYPEDEF: + case BTF_KIND_TYPE_TAG: + next_id = t->type; + break; + case BTF_KIND_ARRAY: { + struct btf_array *a = btf_array(t); + + next_id = a->type; + break; + } + case BTF_KIND_STRUCT: + case BTF_KIND_UNION: + if (next_id < r->nr_dist_base_types) + r->id_map[next_id] = BTF_IS_EMBEDDED; + next_id = 0; + break; + default: + next_id = 0; + break; + } + } + } + + return 0; +} + +/* Build a map from distilled base BTF ids to base BTF ids. To do so, iterate + * through base BTF looking up distilled type (using binary search) equivalents. + */ +static int btf_relocate_map_distilled_base(struct btf_relocate *r) +{ + struct btf_name_info *info, *info_end; + struct btf_type *base_t, *dist_t; + __u8 *base_name_cnt = NULL; + int err = 0; + __u32 id; + + /* generate a sort index array of name/type ids sorted by name for + * distilled base BTF to speed name-based lookups. + */ + info = calloc(r->nr_dist_base_types, sizeof(*info)); + if (!info) { + err = -ENOMEM; + goto done; + } + info_end = info + r->nr_dist_base_types; + for (id = 0; id < r->nr_dist_base_types; id++) { + dist_t = btf_type_by_id(r->dist_base_btf, id); + info[id].name = btf__name_by_offset(r->dist_base_btf, dist_t->name_off); + info[id].id = id; + info[id].size = dist_t->size; + info[id].needs_size = true; + } + qsort(info, r->nr_dist_base_types, sizeof(*info), cmp_btf_name_size); + + /* Mark distilled base struct/union members of split BTF structs/unions + * in id_map with BTF_IS_EMBEDDED; this signals that these types + * need to match both name and size, otherwise embedding the base + * struct/union in the split type is invalid. + */ + for (id = r->nr_dist_base_types; id < r->nr_split_types; id++) { + err = btf_mark_embedded_composite_type_ids(r, id); + if (err) + goto done; + } + + /* Collect name counts for composite types in base BTF. If multiple + * instances of a struct/union of the same name exist, we need to use + * size to determine which to map to since name alone is ambiguous. + */ + base_name_cnt = calloc(r->base_str_len, sizeof(*base_name_cnt)); + if (!base_name_cnt) { + err = -ENOMEM; + goto done; + } + for (id = 1; id < r->nr_base_types; id++) { + base_t = btf_type_by_id(r->base_btf, id); + if (!btf_is_composite(base_t) || !base_t->name_off) + continue; + if (base_name_cnt[base_t->name_off] < 255) + base_name_cnt[base_t->name_off]++; + } + + /* Now search base BTF for matching distilled base BTF types. */ + for (id = 1; id < r->nr_base_types; id++) { + struct btf_name_info *dist_info, base_info = {}; + int dist_kind, base_kind; + + base_t = btf_type_by_id(r->base_btf, id); + /* distilled base consists of named types only. */ + if (!base_t->name_off) + continue; + base_kind = btf_kind(base_t); + base_info.id = id; + base_info.name = btf__name_by_offset(r->base_btf, base_t->name_off); + switch (base_kind) { + case BTF_KIND_INT: + case BTF_KIND_FLOAT: + case BTF_KIND_ENUM: + case BTF_KIND_ENUM64: + /* These types should match both name and size */ + base_info.needs_size = true; + base_info.size = base_t->size; + break; + case BTF_KIND_FWD: + /* No size considerations for fwds. */ + break; + case BTF_KIND_STRUCT: + case BTF_KIND_UNION: + /* Size only needs to be used for struct/union if there + * are multiple types in base BTF with the same name. + * If there are multiple _distilled_ types with the same + * name (a very unlikely scenario), that doesn't matter + * unless corresponding _base_ types to match them are + * missing. + */ + base_info.needs_size = base_name_cnt[base_t->name_off] > 1; + base_info.size = base_t->size; + break; + default: + continue; + } + /* iterate over all matching distilled base types */ + for (dist_info = search_btf_name_size(&base_info, info, r->nr_dist_base_types); + dist_info != NULL && dist_info < info_end && + cmp_btf_name_size(&base_info, dist_info) == 0; + dist_info++) { + if (!dist_info->id || dist_info->id >= r->nr_dist_base_types) { + pr_warn("base BTF id [%d] maps to invalid distilled base BTF id [%d]\n", + id, dist_info->id); + err = -EINVAL; + goto done; + } + dist_t = btf_type_by_id(r->dist_base_btf, dist_info->id); + dist_kind = btf_kind(dist_t); + + /* Validate that the found distilled type is compatible. + * Do not error out on mismatch as another match may + * occur for an identically-named type. + */ + switch (dist_kind) { + case BTF_KIND_FWD: + switch (base_kind) { + case BTF_KIND_FWD: + if (btf_kflag(dist_t) != btf_kflag(base_t)) + continue; + break; + case BTF_KIND_STRUCT: + if (btf_kflag(base_t)) + continue; + break; + case BTF_KIND_UNION: + if (!btf_kflag(base_t)) + continue; + break; + default: + continue; + } + break; + case BTF_KIND_INT: + if (dist_kind != base_kind || + btf_int_encoding(base_t) != btf_int_encoding(dist_t)) + continue; + break; + case BTF_KIND_FLOAT: + if (dist_kind != base_kind) + continue; + break; + case BTF_KIND_ENUM: + /* ENUM and ENUM64 are encoded as sized ENUM in + * distilled base BTF. + */ + if (base_kind != dist_kind && base_kind != BTF_KIND_ENUM64) + continue; + break; + case BTF_KIND_STRUCT: + case BTF_KIND_UNION: + /* size verification is required for embedded + * struct/unions. + */ + if (r->id_map[dist_info->id] == BTF_IS_EMBEDDED && + base_t->size != dist_t->size) + continue; + break; + default: + continue; + } + if (r->id_map[dist_info->id] && + r->id_map[dist_info->id] != BTF_IS_EMBEDDED) { + /* we already have a match; this tells us that + * multiple base types of the same name + * have the same size, since for cases where + * multiple types have the same name we match + * on name and size. In this case, we have + * no way of determining which to relocate + * to in base BTF, so error out. + */ + pr_warn("distilled base BTF type '%s' [%u], size %u has multiple candidates of the same size (ids [%u, %u]) in base BTF\n", + base_info.name, dist_info->id, + base_t->size, id, r->id_map[dist_info->id]); + err = -EINVAL; + goto done; + } + /* map id and name */ + r->id_map[dist_info->id] = id; + r->str_map[dist_t->name_off] = base_t->name_off; + } + } + /* ensure all distilled BTF ids now have a mapping... */ + for (id = 1; id < r->nr_dist_base_types; id++) { + const char *name; + + if (r->id_map[id] && r->id_map[id] != BTF_IS_EMBEDDED) + continue; + dist_t = btf_type_by_id(r->dist_base_btf, id); + name = btf__name_by_offset(r->dist_base_btf, dist_t->name_off); + pr_warn("distilled base BTF type '%s' [%d] is not mapped to base BTF id\n", + name, id); + err = -EINVAL; + break; + } +done: + free(base_name_cnt); + free(info); + return err; +} + +/* distilled base should only have named int/float/enum/fwd/struct/union types. */ +static int btf_relocate_validate_distilled_base(struct btf_relocate *r) +{ + unsigned int i; + + for (i = 1; i < r->nr_dist_base_types; i++) { + struct btf_type *t = btf_type_by_id(r->dist_base_btf, i); + int kind = btf_kind(t); + + switch (kind) { + case BTF_KIND_INT: + case BTF_KIND_FLOAT: + case BTF_KIND_ENUM: + case BTF_KIND_STRUCT: + case BTF_KIND_UNION: + case BTF_KIND_FWD: + if (t->name_off) + break; + pr_warn("type [%d], kind [%d] is invalid for distilled base BTF; it is anonymous\n", + i, kind); + return -EINVAL; + default: + pr_warn("type [%d] in distilled based BTF has unexpected kind [%d]\n", + i, kind); + return -EINVAL; + } + } + return 0; +} + +static int btf_relocate_rewrite_strs(struct btf_relocate *r, __u32 i) +{ + struct btf_type *t = btf_type_by_id(r->btf, i); + struct btf_field_iter it; + __u32 *str_off; + int off, err; + + err = btf_field_iter_init(&it, t, BTF_FIELD_ITER_STRS); + if (err) + return err; + + while ((str_off = btf_field_iter_next(&it))) { + if (!*str_off) + continue; + if (*str_off >= r->dist_str_len) { + *str_off += r->base_str_len - r->dist_str_len; + } else { + off = r->str_map[*str_off]; + if (!off) { + pr_warn("string '%s' [offset %u] is not mapped to base BTF", + btf__str_by_offset(r->btf, off), *str_off); + return -ENOENT; + } + *str_off = off; + } + } + return 0; +} + +/* If successful, output of relocation is updated BTF with base BTF pointing + * at base_btf, and type ids, strings adjusted accordingly. + */ +int btf_relocate(struct btf *btf, const struct btf *base_btf, __u32 **id_map) +{ + unsigned int nr_types = btf__type_cnt(btf); + const struct btf_header *dist_base_hdr; + const struct btf_header *base_hdr; + struct btf_relocate r = {}; + int err = 0; + __u32 id, i; + + r.dist_base_btf = btf__base_btf(btf); + if (!base_btf || r.dist_base_btf == base_btf) + return -EINVAL; + + r.nr_dist_base_types = btf__type_cnt(r.dist_base_btf); + r.nr_base_types = btf__type_cnt(base_btf); + r.nr_split_types = nr_types - r.nr_dist_base_types; + r.btf = btf; + r.base_btf = base_btf; + + r.id_map = calloc(nr_types, sizeof(*r.id_map)); + r.str_map = calloc(btf_header(r.dist_base_btf)->str_len, sizeof(*r.str_map)); + dist_base_hdr = btf_header(r.dist_base_btf); + base_hdr = btf_header(r.base_btf); + r.dist_str_len = dist_base_hdr->str_len; + r.base_str_len = base_hdr->str_len; + if (!r.id_map || !r.str_map) { + err = -ENOMEM; + goto err_out; + } + + err = btf_relocate_validate_distilled_base(&r); + if (err) + goto err_out; + + /* Split BTF ids need to be adjusted as base and distilled base + * have different numbers of types, changing the start id of split + * BTF. + */ + for (id = r.nr_dist_base_types; id < nr_types; id++) + r.id_map[id] = id + r.nr_base_types - r.nr_dist_base_types; + + /* Build a map from distilled base ids to actual base BTF ids; it is used + * to update split BTF id references. Also build a str_map mapping from + * distilled base BTF names to base BTF names. + */ + err = btf_relocate_map_distilled_base(&r); + if (err) + goto err_out; + + /* Next, rewrite type ids in split BTF, replacing split ids with updated + * ids based on number of types in base BTF, and base ids with + * relocated ids from base_btf. + */ + for (i = 0, id = r.nr_dist_base_types; i < r.nr_split_types; i++, id++) { + err = btf_relocate_rewrite_type_id(&r, id); + if (err) + goto err_out; + } + /* String offsets now need to be updated using the str_map. */ + for (i = 0; i < r.nr_split_types; i++) { + err = btf_relocate_rewrite_strs(&r, i + r.nr_dist_base_types); + if (err) + goto err_out; + } + /* Finally reset base BTF to be base_btf */ + btf_set_base_btf(btf, base_btf); + + if (id_map) { + *id_map = r.id_map; + r.id_map = NULL; + } +err_out: + free(r.id_map); + free(r.str_map); + return err; +} diff --git a/tools/lib/bpf/features.c b/tools/lib/bpf/features.c index 4e783cc7fc4b..50befe125ddc 100644 --- a/tools/lib/bpf/features.c +++ b/tools/lib/bpf/features.c @@ -22,7 +22,7 @@ int probe_fd(int fd) static int probe_kern_prog_name(int token_fd) { - const size_t attr_sz = offsetofend(union bpf_attr, prog_name); + const size_t attr_sz = offsetofend(union bpf_attr, prog_token_fd); struct bpf_insn insns[] = { BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN(), @@ -392,11 +392,41 @@ static int probe_uprobe_multi_link(int token_fd) link_fd = bpf_link_create(prog_fd, -1, BPF_TRACE_UPROBE_MULTI, &link_opts); err = -errno; /* close() can clobber errno */ + if (link_fd >= 0 || err != -EBADF) { + if (link_fd >= 0) + close(link_fd); + close(prog_fd); + return 0; + } + + /* Initial multi-uprobe support in kernel didn't handle PID filtering + * correctly (it was doing thread filtering, not process filtering). + * So now we'll detect if PID filtering logic was fixed, and, if not, + * we'll pretend multi-uprobes are not supported, if not. + * Multi-uprobes are used in USDT attachment logic, and we need to be + * conservative here, because multi-uprobe selection happens early at + * load time, while the use of PID filtering is known late at + * attachment time, at which point it's too late to undo multi-uprobe + * selection. + * + * Creating uprobe with pid == -1 for (invalid) '/' binary will fail + * early with -EINVAL on kernels with fixed PID filtering logic; + * otherwise -ESRCH would be returned if passed correct binary path + * (but we'll just get -BADF, of course). + */ + link_opts.uprobe_multi.pid = -1; /* invalid PID */ + link_opts.uprobe_multi.path = "/"; /* invalid path */ + link_opts.uprobe_multi.offsets = &offset; + link_opts.uprobe_multi.cnt = 1; + + link_fd = bpf_link_create(prog_fd, -1, BPF_TRACE_UPROBE_MULTI, &link_opts); + err = -errno; /* close() can clobber errno */ + if (link_fd >= 0) close(link_fd); close(prog_fd); - return link_fd < 0 && err == -EBADF; + return link_fd < 0 && err == -EINVAL; } static int probe_kern_bpf_cookie(int token_fd) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index a2061fcd612d..a3be6f8fac09 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -132,6 +132,7 @@ static const char * const attach_type_name[] = { [BPF_TRACE_UPROBE_MULTI] = "trace_uprobe_multi", [BPF_NETKIT_PRIMARY] = "netkit_primary", [BPF_NETKIT_PEER] = "netkit_peer", + [BPF_TRACE_KPROBE_SESSION] = "trace_kprobe_session", }; static const char * const link_type_name[] = { @@ -149,6 +150,7 @@ static const char * const link_type_name[] = { [BPF_LINK_TYPE_TCX] = "tcx", [BPF_LINK_TYPE_UPROBE_MULTI] = "uprobe_multi", [BPF_LINK_TYPE_NETKIT] = "netkit", + [BPF_LINK_TYPE_SOCKMAP] = "sockmap", }; static const char * const map_type_name[] = { @@ -227,7 +229,30 @@ static const char * const prog_type_name[] = { static int __base_pr(enum libbpf_print_level level, const char *format, va_list args) { - if (level == LIBBPF_DEBUG) + const char *env_var = "LIBBPF_LOG_LEVEL"; + static enum libbpf_print_level min_level = LIBBPF_INFO; + static bool initialized; + + if (!initialized) { + char *verbosity; + + initialized = true; + verbosity = getenv(env_var); + if (verbosity) { + if (strcasecmp(verbosity, "warn") == 0) + min_level = LIBBPF_WARN; + else if (strcasecmp(verbosity, "debug") == 0) + min_level = LIBBPF_DEBUG; + else if (strcasecmp(verbosity, "info") == 0) + min_level = LIBBPF_INFO; + else + fprintf(stderr, "libbpf: unrecognized '%s' envvar value: '%s', should be one of 'warn', 'debug', or 'info'.\n", + env_var, verbosity); + } + } + + /* if too verbose, skip logging */ + if (level > min_level) return 0; return vfprintf(stderr, format, args); @@ -547,6 +572,7 @@ struct bpf_map { bool pinned; bool reused; bool autocreate; + bool autoattach; __u64 map_extra; }; @@ -1126,17 +1152,46 @@ static int bpf_map__init_kern_struct_ops(struct bpf_map *map) const struct btf_type *mtype, *kern_mtype; __u32 mtype_id, kern_mtype_id; void *mdata, *kern_mdata; + struct bpf_program *prog; __s64 msize, kern_msize; __u32 moff, kern_moff; __u32 kern_member_idx; const char *mname; mname = btf__name_by_offset(btf, member->name_off); + moff = member->offset / 8; + mdata = data + moff; + msize = btf__resolve_size(btf, member->type); + if (msize < 0) { + pr_warn("struct_ops init_kern %s: failed to resolve the size of member %s\n", + map->name, mname); + return msize; + } + kern_member = find_member_by_name(kern_btf, kern_type, mname); if (!kern_member) { - pr_warn("struct_ops init_kern %s: Cannot find member %s in kernel BTF\n", + if (!libbpf_is_mem_zeroed(mdata, msize)) { + pr_warn("struct_ops init_kern %s: Cannot find member %s in kernel BTF\n", + map->name, mname); + return -ENOTSUP; + } + + if (st_ops->progs[i]) { + /* If we had declaratively set struct_ops callback, we need to + * force its autoload to false, because it doesn't have + * a chance of succeeding from POV of the current struct_ops map. + * If this program is still referenced somewhere else, though, + * then bpf_object_adjust_struct_ops_autoload() will update its + * autoload accordingly. + */ + st_ops->progs[i]->autoload = false; + st_ops->progs[i] = NULL; + } + + /* Skip all-zero/NULL fields if they are not present in the kernel BTF */ + pr_info("struct_ops %s: member %s not found in kernel, skipping it as it's set to zero\n", map->name, mname); - return -ENOTSUP; + continue; } kern_member_idx = kern_member - btf_members(kern_type); @@ -1147,10 +1202,7 @@ static int bpf_map__init_kern_struct_ops(struct bpf_map *map) return -ENOTSUP; } - moff = member->offset / 8; kern_moff = kern_member->offset / 8; - - mdata = data + moff; kern_mdata = kern_data + kern_moff; mtype = skip_mods_and_typedefs(btf, member->type, &mtype_id); @@ -1165,13 +1217,19 @@ static int bpf_map__init_kern_struct_ops(struct bpf_map *map) } if (btf_is_ptr(mtype)) { - struct bpf_program *prog; + prog = *(void **)mdata; + /* just like for !kern_member case above, reset declaratively + * set (at compile time) program's autload to false, + * if user replaced it with another program or NULL + */ + if (st_ops->progs[i] && st_ops->progs[i] != prog) + st_ops->progs[i]->autoload = false; /* Update the value from the shadow type */ - prog = *(void **)mdata; st_ops->progs[i] = prog; if (!prog) continue; + if (!is_valid_st_ops_program(obj, prog)) { pr_warn("struct_ops init_kern %s: member %s is not a struct_ops program\n", map->name, mname); @@ -1230,9 +1288,8 @@ static int bpf_map__init_kern_struct_ops(struct bpf_map *map) continue; } - msize = btf__resolve_size(btf, mtype_id); kern_msize = btf__resolve_size(kern_btf, kern_mtype_id); - if (msize < 0 || kern_msize < 0 || msize != kern_msize) { + if (kern_msize < 0 || msize != kern_msize) { pr_warn("struct_ops init_kern %s: Error in size of member %s: %zd != %zd(kernel)\n", map->name, mname, (ssize_t)msize, (ssize_t)kern_msize); @@ -1344,6 +1401,7 @@ static int init_struct_ops_maps(struct bpf_object *obj, const char *sec_name, map->def.value_size = type->size; map->def.max_entries = 1; map->def.map_flags = strcmp(sec_name, STRUCT_OPS_LINK_SEC) == 0 ? BPF_F_LINK : 0; + map->autoattach = true; map->st_ops = calloc(1, sizeof(*map->st_ops)); if (!map->st_ops) @@ -1956,6 +2014,20 @@ static struct extern_desc *find_extern_by_name(const struct bpf_object *obj, return NULL; } +static struct extern_desc *find_extern_by_name_with_len(const struct bpf_object *obj, + const void *name, int len) +{ + const char *ext_name; + int i; + + for (i = 0; i < obj->nr_extern; i++) { + ext_name = obj->externs[i].name; + if (strlen(ext_name) == len && strncmp(ext_name, name, len) == 0) + return &obj->externs[i]; + } + return NULL; +} + static int set_kcfg_value_tri(struct extern_desc *ext, void *ext_val, char value) { @@ -4749,6 +4821,20 @@ int bpf_map__set_autocreate(struct bpf_map *map, bool autocreate) return 0; } +int bpf_map__set_autoattach(struct bpf_map *map, bool autoattach) +{ + if (!bpf_map__is_struct_ops(map)) + return libbpf_err(-EINVAL); + + map->autoattach = autoattach; + return 0; +} + +bool bpf_map__autoattach(const struct bpf_map *map) +{ + return map->autoattach; +} + int bpf_map__reuse_fd(struct bpf_map *map, int fd) { struct bpf_map_info info; @@ -7321,11 +7407,15 @@ static int bpf_object_load_prog(struct bpf_object *obj, struct bpf_program *prog char *cp, errmsg[STRERR_BUFSIZE]; size_t log_buf_size = 0; char *log_buf = NULL, *tmp; - int btf_fd, ret, err; bool own_log_buf = true; __u32 log_level = prog->log_level; + int ret, err; - if (prog->type == BPF_PROG_TYPE_UNSPEC) { + /* Be more helpful by rejecting programs that can't be validated early + * with more meaningful and actionable error message. + */ + switch (prog->type) { + case BPF_PROG_TYPE_UNSPEC: /* * The program type must be set. Most likely we couldn't find a proper * section definition at load time, and thus we didn't infer the type. @@ -7333,6 +7423,15 @@ static int bpf_object_load_prog(struct bpf_object *obj, struct bpf_program *prog pr_warn("prog '%s': missing BPF prog type, check ELF section name '%s'\n", prog->name, prog->sec_name); return -EINVAL; + case BPF_PROG_TYPE_STRUCT_OPS: + if (prog->attach_btf_id == 0) { + pr_warn("prog '%s': SEC(\"struct_ops\") program isn't referenced anywhere, did you forget to use it?\n", + prog->name); + return -EINVAL; + } + break; + default: + break; } if (!insns || !insns_cnt) @@ -7347,9 +7446,8 @@ static int bpf_object_load_prog(struct bpf_object *obj, struct bpf_program *prog load_attr.prog_ifindex = prog->prog_ifindex; /* specify func_info/line_info only if kernel supports them */ - btf_fd = btf__fd(obj->btf); - if (btf_fd >= 0 && kernel_supports(obj, FEAT_BTF_FUNC)) { - load_attr.prog_btf_fd = btf_fd; + if (obj->btf && btf__fd(obj->btf) >= 0 && kernel_supports(obj, FEAT_BTF_FUNC)) { + load_attr.prog_btf_fd = btf__fd(obj->btf); load_attr.func_info = prog->func_info; load_attr.func_info_rec_size = prog->func_info_rec_size; load_attr.func_info_cnt = prog->func_info_cnt; @@ -7973,7 +8071,10 @@ static int bpf_object__sanitize_maps(struct bpf_object *obj) return 0; } -int libbpf_kallsyms_parse(kallsyms_cb_t cb, void *ctx) +typedef int (*kallsyms_cb_t)(unsigned long long sym_addr, char sym_type, + const char *sym_name, void *ctx); + +static int libbpf_kallsyms_parse(kallsyms_cb_t cb, void *ctx) { char sym_type, sym_name[500]; unsigned long long sym_addr; @@ -8013,8 +8114,13 @@ static int kallsyms_cb(unsigned long long sym_addr, char sym_type, struct bpf_object *obj = ctx; const struct btf_type *t; struct extern_desc *ext; + char *res; - ext = find_extern_by_name(obj, sym_name); + res = strstr(sym_name, ".llvm."); + if (sym_type == 'd' && res) + ext = find_extern_by_name_with_len(obj, sym_name, res - sym_name); + else + ext = find_extern_by_name(obj, sym_name); if (!ext || ext->type != EXT_KSYM) return 0; @@ -8563,6 +8669,11 @@ int bpf_map__pin(struct bpf_map *map, const char *path) return libbpf_err(-EINVAL); } + if (map->fd < 0) { + pr_warn("map '%s': can't pin BPF map without FD (was it created?)\n", map->name); + return libbpf_err(-EINVAL); + } + if (map->pin_path) { if (path && strcmp(path, map->pin_path)) { pr_warn("map '%s' already has pin path '%s' different from '%s'\n", @@ -9231,6 +9342,7 @@ static int attach_tp(const struct bpf_program *prog, long cookie, struct bpf_lin static int attach_raw_tp(const struct bpf_program *prog, long cookie, struct bpf_link **link); static int attach_trace(const struct bpf_program *prog, long cookie, struct bpf_link **link); static int attach_kprobe_multi(const struct bpf_program *prog, long cookie, struct bpf_link **link); +static int attach_kprobe_session(const struct bpf_program *prog, long cookie, struct bpf_link **link); static int attach_uprobe_multi(const struct bpf_program *prog, long cookie, struct bpf_link **link); static int attach_lsm(const struct bpf_program *prog, long cookie, struct bpf_link **link); static int attach_iter(const struct bpf_program *prog, long cookie, struct bpf_link **link); @@ -9247,6 +9359,7 @@ static const struct bpf_sec_def section_defs[] = { SEC_DEF("uretprobe.s+", KPROBE, 0, SEC_SLEEPABLE, attach_uprobe), SEC_DEF("kprobe.multi+", KPROBE, BPF_TRACE_KPROBE_MULTI, SEC_NONE, attach_kprobe_multi), SEC_DEF("kretprobe.multi+", KPROBE, BPF_TRACE_KPROBE_MULTI, SEC_NONE, attach_kprobe_multi), + SEC_DEF("kprobe.session+", KPROBE, BPF_TRACE_KPROBE_SESSION, SEC_NONE, attach_kprobe_session), SEC_DEF("uprobe.multi+", KPROBE, BPF_TRACE_UPROBE_MULTI, SEC_NONE, attach_uprobe_multi), SEC_DEF("uretprobe.multi+", KPROBE, BPF_TRACE_UPROBE_MULTI, SEC_NONE, attach_uprobe_multi), SEC_DEF("uprobe.multi.s+", KPROBE, BPF_TRACE_UPROBE_MULTI, SEC_SLEEPABLE, attach_uprobe_multi), @@ -9298,6 +9411,7 @@ static const struct bpf_sec_def section_defs[] = { SEC_DEF("sockops", SOCK_OPS, BPF_CGROUP_SOCK_OPS, SEC_ATTACHABLE_OPT), SEC_DEF("sk_skb/stream_parser", SK_SKB, BPF_SK_SKB_STREAM_PARSER, SEC_ATTACHABLE_OPT), SEC_DEF("sk_skb/stream_verdict",SK_SKB, BPF_SK_SKB_STREAM_VERDICT, SEC_ATTACHABLE_OPT), + SEC_DEF("sk_skb/verdict", SK_SKB, BPF_SK_SKB_VERDICT, SEC_ATTACHABLE_OPT), SEC_DEF("sk_skb", SK_SKB, 0, SEC_NONE), SEC_DEF("sk_msg", SK_MSG, BPF_SK_MSG_VERDICT, SEC_ATTACHABLE_OPT), SEC_DEF("lirc_mode2", LIRC_MODE2, BPF_LIRC_MODE2, SEC_ATTACHABLE_OPT), @@ -9816,16 +9930,28 @@ static int find_kernel_btf_id(struct bpf_object *obj, const char *attach_name, enum bpf_attach_type attach_type, int *btf_obj_fd, int *btf_type_id) { - int ret, i; + int ret, i, mod_len; + const char *fn_name, *mod_name = NULL; - ret = find_attach_btf_id(obj->btf_vmlinux, attach_name, attach_type); - if (ret > 0) { - *btf_obj_fd = 0; /* vmlinux BTF */ - *btf_type_id = ret; - return 0; + fn_name = strchr(attach_name, ':'); + if (fn_name) { + mod_name = attach_name; + mod_len = fn_name - mod_name; + fn_name++; + } + + if (!mod_name || strncmp(mod_name, "vmlinux", mod_len) == 0) { + ret = find_attach_btf_id(obj->btf_vmlinux, + mod_name ? fn_name : attach_name, + attach_type); + if (ret > 0) { + *btf_obj_fd = 0; /* vmlinux BTF */ + *btf_type_id = ret; + return 0; + } + if (ret != -ENOENT) + return ret; } - if (ret != -ENOENT) - return ret; ret = load_module_btfs(obj); if (ret) @@ -9834,7 +9960,12 @@ static int find_kernel_btf_id(struct bpf_object *obj, const char *attach_name, for (i = 0; i < obj->btf_module_cnt; i++) { const struct module_btf *mod = &obj->btf_modules[i]; - ret = find_attach_btf_id(mod->btf, attach_name, attach_type); + if (mod_name && strncmp(mod->name, mod_name, mod_len) != 0) + continue; + + ret = find_attach_btf_id(mod->btf, + mod_name ? fn_name : attach_name, + attach_type); if (ret > 0) { *btf_obj_fd = mod->fd; *btf_type_id = ret; @@ -10244,7 +10375,7 @@ __bpf_map__iter(const struct bpf_map *m, const struct bpf_object *obj, int i) struct bpf_map * bpf_object__next_map(const struct bpf_object *obj, const struct bpf_map *prev) { - if (prev == NULL) + if (prev == NULL && obj != NULL) return obj->maps; return __bpf_map__iter(prev, obj, 1); @@ -10253,7 +10384,7 @@ bpf_object__next_map(const struct bpf_object *obj, const struct bpf_map *prev) struct bpf_map * bpf_object__prev_map(const struct bpf_object *obj, const struct bpf_map *next) { - if (next == NULL) { + if (next == NULL && obj != NULL) { if (!obj->nr_maps) return NULL; return obj->maps + obj->nr_maps - 1; @@ -10307,6 +10438,11 @@ static int validate_map_op(const struct bpf_map *map, size_t key_sz, return -EINVAL; } + if (map->fd < 0) { + pr_warn("map '%s': can't use BPF map without FD (was it created?)\n", map->name); + return -EINVAL; + } + if (!check_value_sz) return 0; @@ -10419,8 +10555,15 @@ long libbpf_get_error(const void *ptr) int bpf_link__update_program(struct bpf_link *link, struct bpf_program *prog) { int ret; + int prog_fd = bpf_program__fd(prog); - ret = bpf_link_update(bpf_link__fd(link), bpf_program__fd(prog), NULL); + if (prog_fd < 0) { + pr_warn("prog '%s': can't use BPF program without FD (was it loaded?)\n", + prog->name); + return libbpf_err(-EINVAL); + } + + ret = bpf_link_update(bpf_link__fd(link), prog_fd, NULL); return libbpf_err_errno(ret); } @@ -10614,7 +10757,7 @@ struct bpf_link *bpf_program__attach_perf_event_opts(const struct bpf_program *p } prog_fd = bpf_program__fd(prog); if (prog_fd < 0) { - pr_warn("prog '%s': can't attach BPF program w/o FD (did you load it?)\n", + pr_warn("prog '%s': can't attach BPF program without FD (was it loaded?)\n", prog->name); return libbpf_err_ptr(-EINVAL); } @@ -11326,18 +11469,26 @@ bpf_program__attach_kprobe_multi_opts(const struct bpf_program *prog, struct kprobe_multi_resolve res = { .pattern = pattern, }; + enum bpf_attach_type attach_type; struct bpf_link *link = NULL; char errmsg[STRERR_BUFSIZE]; const unsigned long *addrs; int err, link_fd, prog_fd; + bool retprobe, session; const __u64 *cookies; const char **syms; - bool retprobe; size_t cnt; if (!OPTS_VALID(opts, bpf_kprobe_multi_opts)) return libbpf_err_ptr(-EINVAL); + prog_fd = bpf_program__fd(prog); + if (prog_fd < 0) { + pr_warn("prog '%s': can't attach BPF program without FD (was it loaded?)\n", + prog->name); + return libbpf_err_ptr(-EINVAL); + } + syms = OPTS_GET(opts, syms, false); addrs = OPTS_GET(opts, addrs, false); cnt = OPTS_GET(opts, cnt, false); @@ -11364,6 +11515,12 @@ bpf_program__attach_kprobe_multi_opts(const struct bpf_program *prog, } retprobe = OPTS_GET(opts, retprobe, false); + session = OPTS_GET(opts, session, false); + + if (retprobe && session) + return libbpf_err_ptr(-EINVAL); + + attach_type = session ? BPF_TRACE_KPROBE_SESSION : BPF_TRACE_KPROBE_MULTI; lopts.kprobe_multi.syms = syms; lopts.kprobe_multi.addrs = addrs; @@ -11378,8 +11535,7 @@ bpf_program__attach_kprobe_multi_opts(const struct bpf_program *prog, } link->detach = &bpf_link__detach_fd; - prog_fd = bpf_program__fd(prog); - link_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_KPROBE_MULTI, &lopts); + link_fd = bpf_link_create(prog_fd, 0, attach_type, &lopts); if (link_fd < 0) { err = -errno; pr_warn("prog '%s': failed to attach: %s\n", @@ -11476,7 +11632,7 @@ static int attach_kprobe_multi(const struct bpf_program *prog, long cookie, stru n = sscanf(spec, "%m[a-zA-Z0-9_.*?]", &pattern); if (n < 1) { - pr_warn("kprobe multi pattern is invalid: %s\n", pattern); + pr_warn("kprobe multi pattern is invalid: %s\n", spec); return -EINVAL; } @@ -11485,6 +11641,32 @@ static int attach_kprobe_multi(const struct bpf_program *prog, long cookie, stru return libbpf_get_error(*link); } +static int attach_kprobe_session(const struct bpf_program *prog, long cookie, + struct bpf_link **link) +{ + LIBBPF_OPTS(bpf_kprobe_multi_opts, opts, .session = true); + const char *spec; + char *pattern; + int n; + + *link = NULL; + + /* no auto-attach for SEC("kprobe.session") */ + if (strcmp(prog->sec_name, "kprobe.session") == 0) + return 0; + + spec = prog->sec_name + sizeof("kprobe.session/") - 1; + n = sscanf(spec, "%m[a-zA-Z0-9_.*?]", &pattern); + if (n < 1) { + pr_warn("kprobe session pattern is invalid: %s\n", spec); + return -EINVAL; + } + + *link = bpf_program__attach_kprobe_multi_opts(prog, pattern, &opts); + free(pattern); + return *link ? 0 : -errno; +} + static int attach_uprobe_multi(const struct bpf_program *prog, long cookie, struct bpf_link **link) { char *probe_type = NULL, *binary_path = NULL, *func_name = NULL; @@ -11761,6 +11943,13 @@ bpf_program__attach_uprobe_multi(const struct bpf_program *prog, if (!OPTS_VALID(opts, bpf_uprobe_multi_opts)) return libbpf_err_ptr(-EINVAL); + prog_fd = bpf_program__fd(prog); + if (prog_fd < 0) { + pr_warn("prog '%s': can't attach BPF program without FD (was it loaded?)\n", + prog->name); + return libbpf_err_ptr(-EINVAL); + } + syms = OPTS_GET(opts, syms, NULL); offsets = OPTS_GET(opts, offsets, NULL); ref_ctr_offsets = OPTS_GET(opts, ref_ctr_offsets, NULL); @@ -11836,7 +12025,6 @@ bpf_program__attach_uprobe_multi(const struct bpf_program *prog, } link->detach = &bpf_link__detach_fd; - prog_fd = bpf_program__fd(prog); link_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_UPROBE_MULTI, &lopts); if (link_fd < 0) { err = -errno; @@ -12080,7 +12268,7 @@ struct bpf_link *bpf_program__attach_usdt(const struct bpf_program *prog, return libbpf_err_ptr(-EINVAL); if (bpf_program__fd(prog) < 0) { - pr_warn("prog '%s': can't attach BPF program w/o FD (did you load it?)\n", + pr_warn("prog '%s': can't attach BPF program without FD (was it loaded?)\n", prog->name); return libbpf_err_ptr(-EINVAL); } @@ -12271,13 +12459,19 @@ static int attach_tp(const struct bpf_program *prog, long cookie, struct bpf_lin return libbpf_get_error(*link); } -struct bpf_link *bpf_program__attach_raw_tracepoint(const struct bpf_program *prog, - const char *tp_name) +struct bpf_link * +bpf_program__attach_raw_tracepoint_opts(const struct bpf_program *prog, + const char *tp_name, + struct bpf_raw_tracepoint_opts *opts) { + LIBBPF_OPTS(bpf_raw_tp_opts, raw_opts); char errmsg[STRERR_BUFSIZE]; struct bpf_link *link; int prog_fd, pfd; + if (!OPTS_VALID(opts, bpf_raw_tracepoint_opts)) + return libbpf_err_ptr(-EINVAL); + prog_fd = bpf_program__fd(prog); if (prog_fd < 0) { pr_warn("prog '%s': can't attach before loaded\n", prog->name); @@ -12289,7 +12483,9 @@ struct bpf_link *bpf_program__attach_raw_tracepoint(const struct bpf_program *pr return libbpf_err_ptr(-ENOMEM); link->detach = &bpf_link__detach_fd; - pfd = bpf_raw_tracepoint_open(tp_name, prog_fd); + raw_opts.tp_name = tp_name; + raw_opts.cookie = OPTS_GET(opts, cookie, 0); + pfd = bpf_raw_tracepoint_open_opts(prog_fd, &raw_opts); if (pfd < 0) { pfd = -errno; free(link); @@ -12301,6 +12497,12 @@ struct bpf_link *bpf_program__attach_raw_tracepoint(const struct bpf_program *pr return link; } +struct bpf_link *bpf_program__attach_raw_tracepoint(const struct bpf_program *prog, + const char *tp_name) +{ + return bpf_program__attach_raw_tracepoint_opts(prog, tp_name, NULL); +} + static int attach_raw_tp(const struct bpf_program *prog, long cookie, struct bpf_link **link) { static const char *const prefixes[] = { @@ -12454,6 +12656,12 @@ bpf_program__attach_netns(const struct bpf_program *prog, int netns_fd) return bpf_program_attach_fd(prog, netns_fd, "netns", NULL); } +struct bpf_link * +bpf_program__attach_sockmap(const struct bpf_program *prog, int map_fd) +{ + return bpf_program_attach_fd(prog, map_fd, "sockmap", NULL); +} + struct bpf_link *bpf_program__attach_xdp(const struct bpf_program *prog, int ifindex) { /* target_fd/target_ifindex use the same field in LINK_CREATE */ @@ -12662,6 +12870,12 @@ struct bpf_link *bpf_program__attach(const struct bpf_program *prog) if (!prog->sec_def || !prog->sec_def->prog_attach_fn) return libbpf_err_ptr(-EOPNOTSUPP); + if (bpf_program__fd(prog) < 0) { + pr_warn("prog '%s': can't attach BPF program without FD (was it loaded?)\n", + prog->name); + return libbpf_err_ptr(-EINVAL); + } + err = prog->sec_def->prog_attach_fn(prog, prog->sec_def->cookie, &link); if (err) return libbpf_err_ptr(err); @@ -12702,8 +12916,15 @@ struct bpf_link *bpf_map__attach_struct_ops(const struct bpf_map *map) __u32 zero = 0; int err, fd; - if (!bpf_map__is_struct_ops(map) || map->fd == -1) + if (!bpf_map__is_struct_ops(map)) { + pr_warn("map '%s': can't attach non-struct_ops map\n", map->name); return libbpf_err_ptr(-EINVAL); + } + + if (map->fd < 0) { + pr_warn("map '%s': can't attach BPF map without FD (was it created?)\n", map->name); + return libbpf_err_ptr(-EINVAL); + } link = calloc(1, sizeof(*link)); if (!link) @@ -12751,9 +12972,14 @@ int bpf_link__update_map(struct bpf_link *link, const struct bpf_map *map) __u32 zero = 0; int err; - if (!bpf_map__is_struct_ops(map) || !map_is_created(map)) + if (!bpf_map__is_struct_ops(map)) return -EINVAL; + if (map->fd < 0) { + pr_warn("map '%s': can't use BPF map without FD (was it created?)\n", map->name); + return -EINVAL; + } + st_ops_link = container_of(link, struct bpf_link_struct_ops, link); /* Ensure the type of a link is correct */ if (st_ops_link->map_fd < 0) @@ -13486,14 +13712,15 @@ int libbpf_num_possible_cpus(void) static int populate_skeleton_maps(const struct bpf_object *obj, struct bpf_map_skeleton *maps, - size_t map_cnt) + size_t map_cnt, size_t map_skel_sz) { int i; for (i = 0; i < map_cnt; i++) { - struct bpf_map **map = maps[i].map; - const char *name = maps[i].name; - void **mmaped = maps[i].mmaped; + struct bpf_map_skeleton *map_skel = (void *)maps + i * map_skel_sz; + struct bpf_map **map = map_skel->map; + const char *name = map_skel->name; + void **mmaped = map_skel->mmaped; *map = bpf_object__find_map_by_name(obj, name); if (!*map) { @@ -13510,13 +13737,14 @@ static int populate_skeleton_maps(const struct bpf_object *obj, static int populate_skeleton_progs(const struct bpf_object *obj, struct bpf_prog_skeleton *progs, - size_t prog_cnt) + size_t prog_cnt, size_t prog_skel_sz) { int i; for (i = 0; i < prog_cnt; i++) { - struct bpf_program **prog = progs[i].prog; - const char *name = progs[i].name; + struct bpf_prog_skeleton *prog_skel = (void *)progs + i * prog_skel_sz; + struct bpf_program **prog = prog_skel->prog; + const char *name = prog_skel->name; *prog = bpf_object__find_program_by_name(obj, name); if (!*prog) { @@ -13557,13 +13785,13 @@ int bpf_object__open_skeleton(struct bpf_object_skeleton *s, } *s->obj = obj; - err = populate_skeleton_maps(obj, s->maps, s->map_cnt); + err = populate_skeleton_maps(obj, s->maps, s->map_cnt, s->map_skel_sz); if (err) { pr_warn("failed to populate skeleton maps for '%s': %d\n", s->name, err); return libbpf_err(err); } - err = populate_skeleton_progs(obj, s->progs, s->prog_cnt); + err = populate_skeleton_progs(obj, s->progs, s->prog_cnt, s->prog_skel_sz); if (err) { pr_warn("failed to populate skeleton progs for '%s': %d\n", s->name, err); return libbpf_err(err); @@ -13593,20 +13821,20 @@ int bpf_object__open_subskeleton(struct bpf_object_subskeleton *s) return libbpf_err(-errno); } - err = populate_skeleton_maps(s->obj, s->maps, s->map_cnt); + err = populate_skeleton_maps(s->obj, s->maps, s->map_cnt, s->map_skel_sz); if (err) { pr_warn("failed to populate subskeleton maps: %d\n", err); return libbpf_err(err); } - err = populate_skeleton_progs(s->obj, s->progs, s->prog_cnt); + err = populate_skeleton_progs(s->obj, s->progs, s->prog_cnt, s->prog_skel_sz); if (err) { pr_warn("failed to populate subskeleton maps: %d\n", err); return libbpf_err(err); } for (var_idx = 0; var_idx < s->var_cnt; var_idx++) { - var_skel = &s->vars[var_idx]; + var_skel = (void *)s->vars + var_idx * s->var_skel_sz; map = *var_skel->map; map_type_id = bpf_map__btf_value_type_id(map); map_type = btf__type_by_id(btf, map_type_id); @@ -13653,10 +13881,11 @@ int bpf_object__load_skeleton(struct bpf_object_skeleton *s) } for (i = 0; i < s->map_cnt; i++) { - struct bpf_map *map = *s->maps[i].map; + struct bpf_map_skeleton *map_skel = (void *)s->maps + i * s->map_skel_sz; + struct bpf_map *map = *map_skel->map; size_t mmap_sz = bpf_map_mmap_sz(map); int prot, map_fd = map->fd; - void **mmaped = s->maps[i].mmaped; + void **mmaped = map_skel->mmaped; if (!mmaped) continue; @@ -13704,8 +13933,9 @@ int bpf_object__attach_skeleton(struct bpf_object_skeleton *s) int i, err; for (i = 0; i < s->prog_cnt; i++) { - struct bpf_program *prog = *s->progs[i].prog; - struct bpf_link **link = s->progs[i].link; + struct bpf_prog_skeleton *prog_skel = (void *)s->progs + i * s->prog_skel_sz; + struct bpf_program *prog = *prog_skel->prog; + struct bpf_link **link = prog_skel->link; if (!prog->autoload || !prog->autoattach) continue; @@ -13737,6 +13967,38 @@ int bpf_object__attach_skeleton(struct bpf_object_skeleton *s) */ } + + for (i = 0; i < s->map_cnt; i++) { + struct bpf_map_skeleton *map_skel = (void *)s->maps + i * s->map_skel_sz; + struct bpf_map *map = *map_skel->map; + struct bpf_link **link; + + if (!map->autocreate || !map->autoattach) + continue; + + /* only struct_ops maps can be attached */ + if (!bpf_map__is_struct_ops(map)) + continue; + + /* skeleton is created with earlier version of bpftool, notify user */ + if (s->map_skel_sz < offsetofend(struct bpf_map_skeleton, link)) { + pr_warn("map '%s': BPF skeleton version is old, skipping map auto-attachment...\n", + bpf_map__name(map)); + continue; + } + + link = map_skel->link; + if (*link) + continue; + + *link = bpf_map__attach_struct_ops(map); + if (!*link) { + err = -errno; + pr_warn("map '%s': failed to auto-attach: %d\n", bpf_map__name(map), err); + return libbpf_err(err); + } + } + return 0; } @@ -13745,11 +14007,25 @@ void bpf_object__detach_skeleton(struct bpf_object_skeleton *s) int i; for (i = 0; i < s->prog_cnt; i++) { - struct bpf_link **link = s->progs[i].link; + struct bpf_prog_skeleton *prog_skel = (void *)s->progs + i * s->prog_skel_sz; + struct bpf_link **link = prog_skel->link; bpf_link__destroy(*link); *link = NULL; } + + if (s->map_skel_sz < sizeof(struct bpf_map_skeleton)) + return; + + for (i = 0; i < s->map_cnt; i++) { + struct bpf_map_skeleton *map_skel = (void *)s->maps + i * s->map_skel_sz; + struct bpf_link **link = map_skel->link; + + if (link) { + bpf_link__destroy(*link); + *link = NULL; + } + } } void bpf_object__destroy_skeleton(struct bpf_object_skeleton *s) @@ -13757,8 +14033,7 @@ void bpf_object__destroy_skeleton(struct bpf_object_skeleton *s) if (!s) return; - if (s->progs) - bpf_object__detach_skeleton(s); + bpf_object__detach_skeleton(s); if (s->obj) bpf_object__close(*s->obj); free(s->maps); diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 7b510761f545..64a6a3d323e3 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -98,7 +98,10 @@ typedef int (*libbpf_print_fn_t)(enum libbpf_print_level level, /** * @brief **libbpf_set_print()** sets user-provided log callback function to - * be used for libbpf warnings and informational messages. + * be used for libbpf warnings and informational messages. If the user callback + * is not set, messages are logged to stderr by default. The verbosity of these + * messages can be controlled by setting the environment variable + * LIBBPF_LOG_LEVEL to either warn, info, or debug. * @param fn The log print function. If NULL, libbpf won't print anything. * @return Pointer to old print function. * @@ -539,10 +542,12 @@ struct bpf_kprobe_multi_opts { size_t cnt; /* create return kprobes */ bool retprobe; + /* create session kprobes */ + bool session; size_t :0; }; -#define bpf_kprobe_multi_opts__last_field retprobe +#define bpf_kprobe_multi_opts__last_field session LIBBPF_API struct bpf_link * bpf_program__attach_kprobe_multi_opts(const struct bpf_program *prog, @@ -760,9 +765,20 @@ bpf_program__attach_tracepoint_opts(const struct bpf_program *prog, const char *tp_name, const struct bpf_tracepoint_opts *opts); +struct bpf_raw_tracepoint_opts { + size_t sz; /* size of this struct for forward/backward compatibility */ + __u64 cookie; + size_t :0; +}; +#define bpf_raw_tracepoint_opts__last_field cookie + LIBBPF_API struct bpf_link * bpf_program__attach_raw_tracepoint(const struct bpf_program *prog, const char *tp_name); +LIBBPF_API struct bpf_link * +bpf_program__attach_raw_tracepoint_opts(const struct bpf_program *prog, + const char *tp_name, + struct bpf_raw_tracepoint_opts *opts); struct bpf_trace_opts { /* size of this struct, for forward/backward compatibility */ @@ -784,6 +800,8 @@ bpf_program__attach_cgroup(const struct bpf_program *prog, int cgroup_fd); LIBBPF_API struct bpf_link * bpf_program__attach_netns(const struct bpf_program *prog, int netns_fd); LIBBPF_API struct bpf_link * +bpf_program__attach_sockmap(const struct bpf_program *prog, int map_fd); +LIBBPF_API struct bpf_link * bpf_program__attach_xdp(const struct bpf_program *prog, int ifindex); LIBBPF_API struct bpf_link * bpf_program__attach_freplace(const struct bpf_program *prog, @@ -961,6 +979,23 @@ LIBBPF_API int bpf_map__set_autocreate(struct bpf_map *map, bool autocreate); LIBBPF_API bool bpf_map__autocreate(const struct bpf_map *map); /** + * @brief **bpf_map__set_autoattach()** sets whether libbpf has to auto-attach + * map during BPF skeleton attach phase. + * @param map the BPF map instance + * @param autoattach whether to attach map during BPF skeleton attach phase + * @return 0 on success; negative error code, otherwise + */ +LIBBPF_API int bpf_map__set_autoattach(struct bpf_map *map, bool autoattach); + +/** + * @brief **bpf_map__autoattach()** returns whether BPF map is configured to + * auto-attach during BPF skeleton attach phase. + * @param map the BPF map instance + * @return true if map is set to auto-attach during skeleton attach phase; false, otherwise + */ +LIBBPF_API bool bpf_map__autoattach(const struct bpf_map *map); + +/** * @brief **bpf_map__fd()** gets the file descriptor of the passed * BPF map * @param map the BPF map instance @@ -1282,6 +1317,7 @@ LIBBPF_API int ring_buffer__add(struct ring_buffer *rb, int map_fd, ring_buffer_sample_fn sample_cb, void *ctx); LIBBPF_API int ring_buffer__poll(struct ring_buffer *rb, int timeout_ms); LIBBPF_API int ring_buffer__consume(struct ring_buffer *rb); +LIBBPF_API int ring_buffer__consume_n(struct ring_buffer *rb, size_t n); LIBBPF_API int ring_buffer__epoll_fd(const struct ring_buffer *rb); /** @@ -1356,6 +1392,17 @@ LIBBPF_API int ring__map_fd(const struct ring *r); */ LIBBPF_API int ring__consume(struct ring *r); +/** + * @brief **ring__consume_n()** consumes up to a requested amount of items from + * a ringbuffer without event polling. + * + * @param r A ringbuffer object. + * @param n Maximum amount of items to consume. + * @return The number of items consumed, or a negative number if any of the + * callbacks return an error. + */ +LIBBPF_API int ring__consume_n(struct ring *r, size_t n); + struct user_ring_buffer_opts { size_t sz; /* size of this struct, for forward/backward compatibility */ }; @@ -1642,6 +1689,7 @@ struct bpf_map_skeleton { const char *name; struct bpf_map **map; void **mmaped; + struct bpf_link **link; }; struct bpf_prog_skeleton { diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index 86804fd90dd1..8f0d9ea3b1b4 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -410,7 +410,20 @@ LIBBPF_1.3.0 { LIBBPF_1.4.0 { global: + bpf_program__attach_raw_tracepoint_opts; + bpf_raw_tracepoint_open_opts; bpf_token_create; btf__new_split; btf_ext__raw_data; } LIBBPF_1.3.0; + +LIBBPF_1.5.0 { + global: + btf__distill_base; + btf__relocate; + bpf_map__autoattach; + bpf_map__set_autoattach; + bpf_program__attach_sockmap; + ring__consume_n; + ring_buffer__consume_n; +} LIBBPF_1.4.0; diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h index 864b36177424..408df59e0771 100644 --- a/tools/lib/bpf/libbpf_internal.h +++ b/tools/lib/bpf/libbpf_internal.h @@ -234,6 +234,9 @@ struct btf_type; struct btf_type *btf_type_by_id(const struct btf *btf, __u32 type_id); const char *btf_kind_str(const struct btf_type *t); const struct btf_type *skip_mods_and_typedefs(const struct btf *btf, __u32 id, __u32 *res_id); +const struct btf_header *btf_header(const struct btf *btf); +void btf_set_base_btf(struct btf *btf, const struct btf *base_btf); +int btf_relocate(struct btf *btf, const struct btf *base_btf, __u32 **id_map); static inline enum btf_func_linkage btf_func_linkage(const struct btf_type *t) { @@ -508,21 +511,38 @@ struct bpf_line_info_min { __u32 line_col; }; +enum btf_field_iter_kind { + BTF_FIELD_ITER_IDS, + BTF_FIELD_ITER_STRS, +}; + +struct btf_field_desc { + /* once-per-type offsets */ + int t_off_cnt, t_offs[2]; + /* member struct size, or zero, if no members */ + int m_sz; + /* repeated per-member offsets */ + int m_off_cnt, m_offs[1]; +}; + +struct btf_field_iter { + struct btf_field_desc desc; + void *p; + int m_idx; + int off_idx; + int vlen; +}; + +int btf_field_iter_init(struct btf_field_iter *it, struct btf_type *t, enum btf_field_iter_kind iter_kind); +__u32 *btf_field_iter_next(struct btf_field_iter *it); typedef int (*type_id_visit_fn)(__u32 *type_id, void *ctx); typedef int (*str_off_visit_fn)(__u32 *str_off, void *ctx); -int btf_type_visit_type_ids(struct btf_type *t, type_id_visit_fn visit, void *ctx); -int btf_type_visit_str_offs(struct btf_type *t, str_off_visit_fn visit, void *ctx); int btf_ext_visit_type_ids(struct btf_ext *btf_ext, type_id_visit_fn visit, void *ctx); int btf_ext_visit_str_offs(struct btf_ext *btf_ext, str_off_visit_fn visit, void *ctx); __s32 btf__find_by_name_kind_own(const struct btf *btf, const char *type_name, __u32 kind); -typedef int (*kallsyms_cb_t)(unsigned long long sym_addr, char sym_type, - const char *sym_name, void *ctx); - -int libbpf_kallsyms_parse(kallsyms_cb_t cb, void *arg); - /* handle direct returned errors */ static inline int libbpf_err(int ret) { @@ -602,13 +622,9 @@ static inline int ensure_good_fd(int fd) return fd; } -static inline int sys_dup2(int oldfd, int newfd) +static inline int sys_dup3(int oldfd, int newfd, int flags) { -#ifdef __NR_dup2 - return syscall(__NR_dup2, oldfd, newfd); -#else - return syscall(__NR_dup3, oldfd, newfd, 0); -#endif + return syscall(__NR_dup3, oldfd, newfd, flags); } /* Point *fixed_fd* to the same file that *tmp_fd* points to. @@ -619,7 +635,7 @@ static inline int reuse_fd(int fixed_fd, int tmp_fd) { int err; - err = sys_dup2(tmp_fd, fixed_fd); + err = sys_dup3(tmp_fd, fixed_fd, O_CLOEXEC); err = err < 0 ? -errno : 0; close(tmp_fd); /* clean up temporary FD */ return err; diff --git a/tools/lib/bpf/libbpf_probes.c b/tools/lib/bpf/libbpf_probes.c index 302188122439..9dfbe7750f56 100644 --- a/tools/lib/bpf/libbpf_probes.c +++ b/tools/lib/bpf/libbpf_probes.c @@ -448,7 +448,8 @@ int libbpf_probe_bpf_helper(enum bpf_prog_type prog_type, enum bpf_func_id helpe /* If BPF verifier doesn't recognize BPF helper ID (enum bpf_func_id) * at all, it will emit something like "invalid func unknown#181". * If BPF verifier recognizes BPF helper but it's not supported for - * given BPF program type, it will emit "unknown func bpf_sys_bpf#166". + * given BPF program type, it will emit "unknown func bpf_sys_bpf#166" + * or "program of this type cannot use helper bpf_sys_bpf#166". * In both cases, provided combination of BPF program type and BPF * helper is not supported by the kernel. * In all other cases, probe_prog_load() above will either succeed (e.g., @@ -457,7 +458,8 @@ int libbpf_probe_bpf_helper(enum bpf_prog_type prog_type, enum bpf_func_id helpe * that), or we'll get some more specific BPF verifier error about * some unsatisfied conditions. */ - if (ret == 0 && (strstr(buf, "invalid func ") || strstr(buf, "unknown func "))) + if (ret == 0 && (strstr(buf, "invalid func ") || strstr(buf, "unknown func ") || + strstr(buf, "program of this type cannot use helper "))) return 0; return 1; /* assume supported */ } diff --git a/tools/lib/bpf/libbpf_version.h b/tools/lib/bpf/libbpf_version.h index e783a47da815..d6e5eff967cb 100644 --- a/tools/lib/bpf/libbpf_version.h +++ b/tools/lib/bpf/libbpf_version.h @@ -4,6 +4,6 @@ #define __LIBBPF_VERSION_H #define LIBBPF_MAJOR_VERSION 1 -#define LIBBPF_MINOR_VERSION 4 +#define LIBBPF_MINOR_VERSION 5 #endif /* __LIBBPF_VERSION_H */ diff --git a/tools/lib/bpf/linker.c b/tools/lib/bpf/linker.c index 0d4be829551b..9cd3d4109788 100644 --- a/tools/lib/bpf/linker.c +++ b/tools/lib/bpf/linker.c @@ -957,19 +957,33 @@ static int check_btf_str_off(__u32 *str_off, void *ctx) static int linker_sanity_check_btf(struct src_obj *obj) { struct btf_type *t; - int i, n, err = 0; + int i, n, err; if (!obj->btf) return 0; n = btf__type_cnt(obj->btf); for (i = 1; i < n; i++) { + struct btf_field_iter it; + __u32 *type_id, *str_off; + t = btf_type_by_id(obj->btf, i); - err = err ?: btf_type_visit_type_ids(t, check_btf_type_id, obj->btf); - err = err ?: btf_type_visit_str_offs(t, check_btf_str_off, obj->btf); + err = btf_field_iter_init(&it, t, BTF_FIELD_ITER_IDS); + if (err) + return err; + while ((type_id = btf_field_iter_next(&it))) { + if (*type_id >= n) + return -EINVAL; + } + + err = btf_field_iter_init(&it, t, BTF_FIELD_ITER_STRS); if (err) return err; + while ((str_off = btf_field_iter_next(&it))) { + if (!btf__str_by_offset(obj->btf, *str_off)) + return -EINVAL; + } } return 0; @@ -2213,10 +2227,17 @@ static int linker_fixup_btf(struct src_obj *obj) vi = btf_var_secinfos(t); for (j = 0, m = btf_vlen(t); j < m; j++, vi++) { const struct btf_type *vt = btf__type_by_id(obj->btf, vi->type); - const char *var_name = btf__str_by_offset(obj->btf, vt->name_off); - int var_linkage = btf_var(vt)->linkage; + const char *var_name; + int var_linkage; Elf64_Sym *sym; + /* could be a variable or function */ + if (!btf_is_var(vt)) + continue; + + var_name = btf__str_by_offset(obj->btf, vt->name_off); + var_linkage = btf_var(vt)->linkage; + /* no need to patch up static or extern vars */ if (var_linkage != BTF_VAR_GLOBAL_ALLOCATED) continue; @@ -2234,26 +2255,10 @@ static int linker_fixup_btf(struct src_obj *obj) return 0; } -static int remap_type_id(__u32 *type_id, void *ctx) -{ - int *id_map = ctx; - int new_id = id_map[*type_id]; - - /* Error out if the type wasn't remapped. Ignore VOID which stays VOID. */ - if (new_id == 0 && *type_id != 0) { - pr_warn("failed to find new ID mapping for original BTF type ID %u\n", *type_id); - return -EINVAL; - } - - *type_id = id_map[*type_id]; - - return 0; -} - static int linker_append_btf(struct bpf_linker *linker, struct src_obj *obj) { const struct btf_type *t; - int i, j, n, start_id, id; + int i, j, n, start_id, id, err; const char *name; if (!obj->btf) @@ -2324,9 +2329,25 @@ static int linker_append_btf(struct bpf_linker *linker, struct src_obj *obj) n = btf__type_cnt(linker->btf); for (i = start_id; i < n; i++) { struct btf_type *dst_t = btf_type_by_id(linker->btf, i); + struct btf_field_iter it; + __u32 *type_id; - if (btf_type_visit_type_ids(dst_t, remap_type_id, obj->btf_type_map)) - return -EINVAL; + err = btf_field_iter_init(&it, dst_t, BTF_FIELD_ITER_IDS); + if (err) + return err; + + while ((type_id = btf_field_iter_next(&it))) { + int new_id = obj->btf_type_map[*type_id]; + + /* Error out if the type wasn't remapped. Ignore VOID which stays VOID. */ + if (new_id == 0 && *type_id != 0) { + pr_warn("failed to find new ID mapping for original BTF type ID %u\n", + *type_id); + return -EINVAL; + } + + *type_id = obj->btf_type_map[*type_id]; + } } /* Rewrite VAR/FUNC underlying types (i.e., FUNC's FUNC_PROTO and VAR's diff --git a/tools/lib/bpf/ringbuf.c b/tools/lib/bpf/ringbuf.c index aacb64278a01..bfd8dac4c0cc 100644 --- a/tools/lib/bpf/ringbuf.c +++ b/tools/lib/bpf/ringbuf.c @@ -231,7 +231,7 @@ static inline int roundup_len(__u32 len) return (len + 7) / 8 * 8; } -static int64_t ringbuf_process_ring(struct ring *r) +static int64_t ringbuf_process_ring(struct ring *r, size_t n) { int *len_ptr, len, err; /* 64-bit to avoid overflow in case of extreme application behavior */ @@ -268,12 +268,42 @@ static int64_t ringbuf_process_ring(struct ring *r) } smp_store_release(r->consumer_pos, cons_pos); + + if (cnt >= n) + goto done; } } while (got_new_data); done: return cnt; } +/* Consume available ring buffer(s) data without event polling, up to n + * records. + * + * Returns number of records consumed across all registered ring buffers (or + * n, whichever is less), or negative number if any of the callbacks return + * error. + */ +int ring_buffer__consume_n(struct ring_buffer *rb, size_t n) +{ + int64_t err, res = 0; + int i; + + for (i = 0; i < rb->ring_cnt; i++) { + struct ring *ring = rb->rings[i]; + + err = ringbuf_process_ring(ring, n); + if (err < 0) + return libbpf_err(err); + res += err; + n -= err; + + if (n == 0) + break; + } + return res > INT_MAX ? INT_MAX : res; +} + /* Consume available ring buffer(s) data without event polling. * Returns number of records consumed across all registered ring buffers (or * INT_MAX, whichever is less), or negative number if any of the callbacks @@ -287,13 +317,15 @@ int ring_buffer__consume(struct ring_buffer *rb) for (i = 0; i < rb->ring_cnt; i++) { struct ring *ring = rb->rings[i]; - err = ringbuf_process_ring(ring); + err = ringbuf_process_ring(ring, INT_MAX); if (err < 0) return libbpf_err(err); res += err; + if (res > INT_MAX) { + res = INT_MAX; + break; + } } - if (res > INT_MAX) - return INT_MAX; return res; } @@ -314,13 +346,13 @@ int ring_buffer__poll(struct ring_buffer *rb, int timeout_ms) __u32 ring_id = rb->events[i].data.fd; struct ring *ring = rb->rings[ring_id]; - err = ringbuf_process_ring(ring); + err = ringbuf_process_ring(ring, INT_MAX); if (err < 0) return libbpf_err(err); res += err; } if (res > INT_MAX) - return INT_MAX; + res = INT_MAX; return res; } @@ -371,17 +403,22 @@ int ring__map_fd(const struct ring *r) return r->map_fd; } -int ring__consume(struct ring *r) +int ring__consume_n(struct ring *r, size_t n) { int64_t res; - res = ringbuf_process_ring(r); + res = ringbuf_process_ring(r, n); if (res < 0) return libbpf_err(res); return res > INT_MAX ? INT_MAX : res; } +int ring__consume(struct ring *r) +{ + return ring__consume_n(r, INT_MAX); +} + static void user_ringbuf_unmap_ring(struct user_ring_buffer *rb) { if (rb->consumer_pos) { diff --git a/tools/lib/bpf/str_error.c b/tools/lib/bpf/str_error.c index 146da01979c7..5e6a1e27ddf9 100644 --- a/tools/lib/bpf/str_error.c +++ b/tools/lib/bpf/str_error.c @@ -2,6 +2,7 @@ #undef _GNU_SOURCE #include <string.h> #include <stdio.h> +#include <errno.h> #include "str_error.h" /* make sure libbpf doesn't use kernel-only integer typedefs */ @@ -15,7 +16,18 @@ char *libbpf_strerror_r(int err, char *dst, int len) { int ret = strerror_r(err < 0 ? -err : err, dst, len); - if (ret) - snprintf(dst, len, "ERROR: strerror_r(%d)=%d", err, ret); + /* on glibc <2.13, ret == -1 and errno is set, if strerror_r() can't + * handle the error, on glibc >=2.13 *positive* (errno-like) error + * code is returned directly + */ + if (ret == -1) + ret = errno; + if (ret) { + if (ret == EINVAL) + /* strerror_r() doesn't recognize this specific error */ + snprintf(dst, len, "unknown error (%d)", err < 0 ? err : -err); + else + snprintf(dst, len, "ERROR: strerror_r(%d)=%d", err, ret); + } return dst; } diff --git a/tools/lib/bpf/usdt.bpf.h b/tools/lib/bpf/usdt.bpf.h index f6763300b26a..76359bcdc94a 100644 --- a/tools/lib/bpf/usdt.bpf.h +++ b/tools/lib/bpf/usdt.bpf.h @@ -214,18 +214,18 @@ long bpf_usdt_cookie(struct pt_regs *ctx) /* we rely on ___bpf_apply() and ___bpf_narg() macros already defined in bpf_tracing.h */ #define ___bpf_usdt_args0() ctx -#define ___bpf_usdt_args1(x) ___bpf_usdt_args0(), ({ long _x; bpf_usdt_arg(ctx, 0, &_x); (void *)_x; }) -#define ___bpf_usdt_args2(x, args...) ___bpf_usdt_args1(args), ({ long _x; bpf_usdt_arg(ctx, 1, &_x); (void *)_x; }) -#define ___bpf_usdt_args3(x, args...) ___bpf_usdt_args2(args), ({ long _x; bpf_usdt_arg(ctx, 2, &_x); (void *)_x; }) -#define ___bpf_usdt_args4(x, args...) ___bpf_usdt_args3(args), ({ long _x; bpf_usdt_arg(ctx, 3, &_x); (void *)_x; }) -#define ___bpf_usdt_args5(x, args...) ___bpf_usdt_args4(args), ({ long _x; bpf_usdt_arg(ctx, 4, &_x); (void *)_x; }) -#define ___bpf_usdt_args6(x, args...) ___bpf_usdt_args5(args), ({ long _x; bpf_usdt_arg(ctx, 5, &_x); (void *)_x; }) -#define ___bpf_usdt_args7(x, args...) ___bpf_usdt_args6(args), ({ long _x; bpf_usdt_arg(ctx, 6, &_x); (void *)_x; }) -#define ___bpf_usdt_args8(x, args...) ___bpf_usdt_args7(args), ({ long _x; bpf_usdt_arg(ctx, 7, &_x); (void *)_x; }) -#define ___bpf_usdt_args9(x, args...) ___bpf_usdt_args8(args), ({ long _x; bpf_usdt_arg(ctx, 8, &_x); (void *)_x; }) -#define ___bpf_usdt_args10(x, args...) ___bpf_usdt_args9(args), ({ long _x; bpf_usdt_arg(ctx, 9, &_x); (void *)_x; }) -#define ___bpf_usdt_args11(x, args...) ___bpf_usdt_args10(args), ({ long _x; bpf_usdt_arg(ctx, 10, &_x); (void *)_x; }) -#define ___bpf_usdt_args12(x, args...) ___bpf_usdt_args11(args), ({ long _x; bpf_usdt_arg(ctx, 11, &_x); (void *)_x; }) +#define ___bpf_usdt_args1(x) ___bpf_usdt_args0(), ({ long _x; bpf_usdt_arg(ctx, 0, &_x); _x; }) +#define ___bpf_usdt_args2(x, args...) ___bpf_usdt_args1(args), ({ long _x; bpf_usdt_arg(ctx, 1, &_x); _x; }) +#define ___bpf_usdt_args3(x, args...) ___bpf_usdt_args2(args), ({ long _x; bpf_usdt_arg(ctx, 2, &_x); _x; }) +#define ___bpf_usdt_args4(x, args...) ___bpf_usdt_args3(args), ({ long _x; bpf_usdt_arg(ctx, 3, &_x); _x; }) +#define ___bpf_usdt_args5(x, args...) ___bpf_usdt_args4(args), ({ long _x; bpf_usdt_arg(ctx, 4, &_x); _x; }) +#define ___bpf_usdt_args6(x, args...) ___bpf_usdt_args5(args), ({ long _x; bpf_usdt_arg(ctx, 5, &_x); _x; }) +#define ___bpf_usdt_args7(x, args...) ___bpf_usdt_args6(args), ({ long _x; bpf_usdt_arg(ctx, 6, &_x); _x; }) +#define ___bpf_usdt_args8(x, args...) ___bpf_usdt_args7(args), ({ long _x; bpf_usdt_arg(ctx, 7, &_x); _x; }) +#define ___bpf_usdt_args9(x, args...) ___bpf_usdt_args8(args), ({ long _x; bpf_usdt_arg(ctx, 8, &_x); _x; }) +#define ___bpf_usdt_args10(x, args...) ___bpf_usdt_args9(args), ({ long _x; bpf_usdt_arg(ctx, 9, &_x); _x; }) +#define ___bpf_usdt_args11(x, args...) ___bpf_usdt_args10(args), ({ long _x; bpf_usdt_arg(ctx, 10, &_x); _x; }) +#define ___bpf_usdt_args12(x, args...) ___bpf_usdt_args11(args), ({ long _x; bpf_usdt_arg(ctx, 11, &_x); _x; }) #define ___bpf_usdt_args(args...) ___bpf_apply(___bpf_usdt_args, ___bpf_narg(args))(args) /* diff --git a/tools/lib/list_sort.c b/tools/lib/list_sort.c index 10c067e3a8d2..69affa251fa7 100644 --- a/tools/lib/list_sort.c +++ b/tools/lib/list_sort.c @@ -52,7 +52,6 @@ static void merge_final(void *priv, list_cmp_func_t cmp, struct list_head *head, struct list_head *a, struct list_head *b) { struct list_head *tail = head; - u8 count = 0; for (;;) { /* if equal, take 'a' -- important for sort stability */ @@ -78,15 +77,6 @@ static void merge_final(void *priv, list_cmp_func_t cmp, struct list_head *head, /* Finish linking remainder of list b on to tail */ tail->next = b; do { - /* - * If the merge is highly unbalanced (e.g. the input is - * already sorted), this loop may run many iterations. - * Continue callbacks to the client even though no - * element comparison is needed, so the client's cmp() - * routine can invoke cond_resched() periodically. - */ - if (unlikely(!++count)) - cmp(priv, b, b); b->prev = tail; tail = b; b = b->next; diff --git a/tools/lib/perf/cpumap.c b/tools/lib/perf/cpumap.c index 4adcd7920d03..cae799ad44e1 100644 --- a/tools/lib/perf/cpumap.c +++ b/tools/lib/perf/cpumap.c @@ -18,9 +18,13 @@ void perf_cpu_map__set_nr(struct perf_cpu_map *map, int nr_cpus) struct perf_cpu_map *perf_cpu_map__alloc(int nr_cpus) { - RC_STRUCT(perf_cpu_map) *cpus = malloc(sizeof(*cpus) + sizeof(struct perf_cpu) * nr_cpus); + RC_STRUCT(perf_cpu_map) *cpus; struct perf_cpu_map *result; + if (nr_cpus == 0) + return NULL; + + cpus = malloc(sizeof(*cpus) + sizeof(struct perf_cpu) * nr_cpus); if (ADD_RC_CHK(result, cpus)) { cpus->nr = nr_cpus; refcount_set(&cpus->refcnt, 1); @@ -316,6 +320,19 @@ bool perf_cpu_map__has_any_cpu_or_is_empty(const struct perf_cpu_map *map) return map ? __perf_cpu_map__cpu(map, 0).cpu == -1 : true; } +bool perf_cpu_map__is_any_cpu_or_is_empty(const struct perf_cpu_map *map) +{ + if (!map) + return true; + + return __perf_cpu_map__nr(map) == 1 && __perf_cpu_map__cpu(map, 0).cpu == -1; +} + +bool perf_cpu_map__is_empty(const struct perf_cpu_map *map) +{ + return map == NULL; +} + int perf_cpu_map__idx(const struct perf_cpu_map *cpus, struct perf_cpu cpu) { int low, high; @@ -372,6 +389,20 @@ bool perf_cpu_map__has_any_cpu(const struct perf_cpu_map *map) return map && __perf_cpu_map__cpu(map, 0).cpu == -1; } +struct perf_cpu perf_cpu_map__min(const struct perf_cpu_map *map) +{ + struct perf_cpu cpu, result = { + .cpu = -1 + }; + int idx; + + perf_cpu_map__for_each_cpu_skip_any(cpu, idx, map) { + result = cpu; + break; + } + return result; +} + struct perf_cpu perf_cpu_map__max(const struct perf_cpu_map *map) { struct perf_cpu result = { diff --git a/tools/lib/perf/include/perf/cpumap.h b/tools/lib/perf/include/perf/cpumap.h index 228c6c629b0c..90457d17fb2f 100644 --- a/tools/lib/perf/include/perf/cpumap.h +++ b/tools/lib/perf/include/perf/cpumap.h @@ -61,6 +61,22 @@ LIBPERF_API int perf_cpu_map__nr(const struct perf_cpu_map *cpus); * perf_cpu_map__has_any_cpu_or_is_empty - is map either empty or has the "any CPU"/dummy value. */ LIBPERF_API bool perf_cpu_map__has_any_cpu_or_is_empty(const struct perf_cpu_map *map); +/** + * perf_cpu_map__is_any_cpu_or_is_empty - is map either empty or the "any CPU"/dummy value. + */ +LIBPERF_API bool perf_cpu_map__is_any_cpu_or_is_empty(const struct perf_cpu_map *map); +/** + * perf_cpu_map__is_empty - does the map contain no values and it doesn't + * contain the special "any CPU"/dummy value. + */ +LIBPERF_API bool perf_cpu_map__is_empty(const struct perf_cpu_map *map); +/** + * perf_cpu_map__min - the minimum CPU value or -1 if empty or just the "any CPU"/dummy value. + */ +LIBPERF_API struct perf_cpu perf_cpu_map__min(const struct perf_cpu_map *map); +/** + * perf_cpu_map__max - the maximum CPU value or -1 if empty or just the "any CPU"/dummy value. + */ LIBPERF_API struct perf_cpu perf_cpu_map__max(const struct perf_cpu_map *map); LIBPERF_API bool perf_cpu_map__has(const struct perf_cpu_map *map, struct perf_cpu cpu); LIBPERF_API bool perf_cpu_map__equal(const struct perf_cpu_map *lhs, diff --git a/tools/lib/perf/include/perf/event.h b/tools/lib/perf/include/perf/event.h index ae64090184d3..37bb7771d914 100644 --- a/tools/lib/perf/include/perf/event.h +++ b/tools/lib/perf/include/perf/event.h @@ -77,6 +77,12 @@ struct perf_record_lost_samples { __u64 lost; }; +#define MAX_ID_HDR_ENTRIES 6 +struct perf_record_lost_samples_and_ids { + struct perf_record_lost_samples lost; + __u64 sample_ids[MAX_ID_HDR_ENTRIES]; +}; + /* * PERF_FORMAT_ENABLED | PERF_FORMAT_RUNNING | PERF_FORMAT_ID | PERF_FORMAT_LOST */ diff --git a/tools/lib/perf/libperf.map b/tools/lib/perf/libperf.map index 10b3f3722642..2aa79b696032 100644 --- a/tools/lib/perf/libperf.map +++ b/tools/lib/perf/libperf.map @@ -10,6 +10,10 @@ LIBPERF_0.0.1 { perf_cpu_map__nr; perf_cpu_map__cpu; perf_cpu_map__has_any_cpu_or_is_empty; + perf_cpu_map__is_any_cpu_or_is_empty; + perf_cpu_map__is_empty; + perf_cpu_map__has_any_cpu; + perf_cpu_map__min; perf_cpu_map__max; perf_cpu_map__has; perf_thread_map__new_array; diff --git a/tools/lib/perf/mmap.c b/tools/lib/perf/mmap.c index 0c903c2372c9..c1a51d925e0e 100644 --- a/tools/lib/perf/mmap.c +++ b/tools/lib/perf/mmap.c @@ -279,7 +279,7 @@ union perf_event *perf_mmap__read_event(struct perf_mmap *map) if (!refcount_read(&map->refcnt)) return NULL; - /* non-overwirte doesn't pause the ringbuffer */ + /* non-overwrite doesn't pause the ringbuffer */ if (!map->overwrite) map->end = perf_mmap__read_head(map); diff --git a/tools/lib/rbtree.c b/tools/lib/rbtree.c index 727396de6be5..9e7307186b7f 100644 --- a/tools/lib/rbtree.c +++ b/tools/lib/rbtree.c @@ -58,7 +58,7 @@ static inline void rb_set_black(struct rb_node *rb) { - rb->__rb_parent_color |= RB_BLACK; + rb->__rb_parent_color += RB_BLACK; } static inline struct rb_node *rb_red_parent(struct rb_node *red) diff --git a/tools/lib/subcmd/parse-options.c b/tools/lib/subcmd/parse-options.c index 9fa75943f2ed..4b60ec03b0bb 100644 --- a/tools/lib/subcmd/parse-options.c +++ b/tools/lib/subcmd/parse-options.c @@ -633,11 +633,10 @@ int parse_options_subcommand(int argc, const char **argv, const struct option *o const char *const subcommands[], const char *usagestr[], int flags) { struct parse_opt_ctx_t ctx; + char *buf = NULL; /* build usage string if it's not provided */ if (subcommands && !usagestr[0]) { - char *buf = NULL; - astrcatf(&buf, "%s %s [<options>] {", subcmd_config.exec_name, argv[0]); for (int i = 0; subcommands[i]; i++) { @@ -679,7 +678,10 @@ int parse_options_subcommand(int argc, const char **argv, const struct option *o astrcatf(&error_buf, "unknown switch `%c'", *ctx.opt); usage_with_options(usagestr, options); } - + if (buf) { + usagestr[0] = NULL; + free(buf); + } return parse_options_end(&ctx); } @@ -806,18 +808,30 @@ static int option__cmp(const void *va, const void *vb) static struct option *options__order(const struct option *opts) { - int nr_opts = 0, nr_group = 0, len; - const struct option *o = opts; - struct option *opt, *ordered, *group; - - for (o = opts; o->type != OPTION_END; o++) - ++nr_opts; - - len = sizeof(*o) * (nr_opts + 1); - ordered = malloc(len); - if (!ordered) - goto out; - memcpy(ordered, opts, len); + int nr_opts = 0, nr_group = 0, nr_parent = 0, len; + const struct option *o, *p = opts; + struct option *opt, *ordered = NULL, *group; + + /* flatten the options that have parents */ + for (p = opts; p != NULL; p = o->parent) { + for (o = p; o->type != OPTION_END; o++) + ++nr_opts; + + /* + * the length is given by the number of options plus a null + * terminator for the last loop iteration. + */ + len = sizeof(*o) * (nr_opts + !o->parent); + group = realloc(ordered, len); + if (!group) + goto out; + ordered = group; + memcpy(&ordered[nr_parent], p, sizeof(*o) * (nr_opts - nr_parent)); + + nr_parent = nr_opts; + } + /* copy the last OPTION_END */ + memcpy(&ordered[nr_opts], o, sizeof(*o)); /* sort each option group individually */ for (opt = group = ordered; opt->type != OPTION_END; opt++) { diff --git a/tools/lib/subcmd/run-command.c b/tools/lib/subcmd/run-command.c index d435eb42354b..4e3a557a2f37 100644 --- a/tools/lib/subcmd/run-command.c +++ b/tools/lib/subcmd/run-command.c @@ -165,43 +165,65 @@ int start_command(struct child_process *cmd) return 0; } -static int wait_or_whine(pid_t pid) +static int wait_or_whine(struct child_process *cmd, bool block) { - char sbuf[STRERR_BUFSIZE]; + bool finished = cmd->finished; + int result = cmd->finish_result; - for (;;) { + while (!finished) { int status, code; - pid_t waiting = waitpid(pid, &status, 0); + pid_t waiting = waitpid(cmd->pid, &status, block ? 0 : WNOHANG); + + if (!block && waiting == 0) + break; + + if (waiting < 0 && errno == EINTR) + continue; + finished = true; if (waiting < 0) { - if (errno == EINTR) - continue; + char sbuf[STRERR_BUFSIZE]; + fprintf(stderr, " Error: waitpid failed (%s)", str_error_r(errno, sbuf, sizeof(sbuf))); - return -ERR_RUN_COMMAND_WAITPID; - } - if (waiting != pid) - return -ERR_RUN_COMMAND_WAITPID_WRONG_PID; - if (WIFSIGNALED(status)) - return -ERR_RUN_COMMAND_WAITPID_SIGNAL; - - if (!WIFEXITED(status)) - return -ERR_RUN_COMMAND_WAITPID_NOEXIT; - code = WEXITSTATUS(status); - switch (code) { - case 127: - return -ERR_RUN_COMMAND_EXEC; - case 0: - return 0; - default: - return -code; + result = -ERR_RUN_COMMAND_WAITPID; + } else if (waiting != cmd->pid) { + result = -ERR_RUN_COMMAND_WAITPID_WRONG_PID; + } else if (WIFSIGNALED(status)) { + result = -ERR_RUN_COMMAND_WAITPID_SIGNAL; + } else if (!WIFEXITED(status)) { + result = -ERR_RUN_COMMAND_WAITPID_NOEXIT; + } else { + code = WEXITSTATUS(status); + switch (code) { + case 127: + result = -ERR_RUN_COMMAND_EXEC; + break; + case 0: + result = 0; + break; + default: + result = -code; + break; + } } } + if (finished) { + cmd->finished = 1; + cmd->finish_result = result; + } + return result; +} + +int check_if_command_finished(struct child_process *cmd) +{ + wait_or_whine(cmd, /*block=*/false); + return cmd->finished; } int finish_command(struct child_process *cmd) { - return wait_or_whine(cmd->pid); + return wait_or_whine(cmd, /*block=*/true); } int run_command(struct child_process *cmd) diff --git a/tools/lib/subcmd/run-command.h b/tools/lib/subcmd/run-command.h index d794138a797f..b2d39de6e690 100644 --- a/tools/lib/subcmd/run-command.h +++ b/tools/lib/subcmd/run-command.h @@ -41,17 +41,20 @@ struct child_process { int err; const char *dir; const char *const *env; + int finish_result; unsigned no_stdin:1; unsigned no_stdout:1; unsigned no_stderr:1; unsigned exec_cmd:1; /* if this is to be external sub-command */ unsigned stdout_to_stderr:1; + unsigned finished:1; void (*preexec_cb)(void); /* If set, call function in child rather than doing an exec. */ int (*no_exec_cmd)(struct child_process *process); }; int start_command(struct child_process *); +int check_if_command_finished(struct child_process *); int finish_command(struct child_process *); int run_command(struct child_process *); |