Create `src/nolibc.c` to provide libc functions like `memset()`, `malloc()` and `free()`. Only build this file when we build liburing without libc. Add `get_page_size()` function to get the page size. When we build with libc, it uses `sysconf(_SC_PAGESIZE)`, otherwise it uses arch dependent implementation function that we provide at `src/arch` dir. Add conditional preprocessor in `src/syscall.h` to use arch dependent syscalls written in Assembly when we build liburing without libc. Extra notes for tests: 1) Functions in `src/syscall.c` require libc to work. 2) Tests require functions in `src/syscall.c`. So we build `src/syscall.c` manually from the test's Makefile. The Makefile in `src/` dir still builds `src/syscall.c` when we build liburing with libc. Link: https://github.com/axboe/liburing/issues/443 Reviewed-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Ammar Faizi <ammar.faizi@xxxxxxxxxxxxxxxxxxxxx> --- src/lib.h | 44 +++++++++++++++++++++++++++++++ src/nolibc.c | 48 ++++++++++++++++++++++++++++++++++ src/queue.c | 14 +++------- src/register.c | 12 +++------ src/setup.c | 17 +++--------- src/syscall.c | 11 +++++++- src/syscall.h | 71 +++++++++++++++++++++++++++++++++++++++----------- test/Makefile | 19 +++++++++++--- 8 files changed, 183 insertions(+), 53 deletions(-) create mode 100644 src/lib.h create mode 100644 src/nolibc.c diff --git a/src/lib.h b/src/lib.h new file mode 100644 index 0000000..58d91be --- /dev/null +++ b/src/lib.h @@ -0,0 +1,44 @@ +/* SPDX-License-Identifier: MIT */ +#ifndef LIBURING_LIB_H +#define LIBURING_LIB_H + +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#ifdef CONFIG_NOLIBC +# if defined(__x86_64__) || defined(__i386__) +# include "arch/x86/lib.h" +# else +# error "This arch doesn't support building liburing without libc" +# endif +#endif + +#ifndef offsetof +# define offsetof(TYPE, FIELD) ((size_t) &((TYPE *)0)->FIELD) +#endif + +#ifndef container_of +# define container_of(PTR, TYPE, FIELD) ({ \ + __typeof__(((TYPE *)0)->FIELD) *__FIELD_PTR = (PTR); \ + (TYPE *)((char *) __FIELD_PTR - offsetof(TYPE, FIELD)); \ +}) +#endif + + +static inline long get_page_size(void) +{ +#ifdef CONFIG_NOLIBC + return __arch_impl_get_page_size(); +#else + long page_size; + + page_size = sysconf(_SC_PAGESIZE); + if (page_size < 0) + page_size = 4096; + + return page_size; +#endif +} + +#endif /* #ifndef LIBURING_LIB_H */ diff --git a/src/nolibc.c b/src/nolibc.c new file mode 100644 index 0000000..5582ca0 --- /dev/null +++ b/src/nolibc.c @@ -0,0 +1,48 @@ +/* SPDX-License-Identifier: MIT */ + +#ifndef CONFIG_NOLIBC +# error "This file should only be compiled for no libc build" +#endif + +#include "lib.h" +#include "syscall.h" + +void *memset(void *s, int c, size_t n) +{ + size_t i; + unsigned char *p = s; + + for (i = 0; i < n; i++) + p[i] = (unsigned char) c; + + return s; +} + +struct uring_heap { + size_t len; + char user_p[]; +}; + +void *malloc(size_t len) +{ + struct uring_heap *heap; + + heap = uring_mmap(NULL, sizeof(*heap) + len, PROT_READ | PROT_WRITE, + MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); + if (IS_ERR(heap)) + return NULL; + + heap->len = sizeof(*heap) + len; + return heap->user_p; +} + +void free(void *p) +{ + struct uring_heap *heap; + + if (uring_unlikely(!p)) + return; + + heap = container_of(p, struct uring_heap, user_p); + uring_munmap(heap, heap->len); +} diff --git a/src/queue.c b/src/queue.c index 9af29d5..eb0c736 100644 --- a/src/queue.c +++ b/src/queue.c @@ -1,19 +1,11 @@ /* SPDX-License-Identifier: MIT */ #define _POSIX_C_SOURCE 200112L -#include <sys/types.h> -#include <sys/stat.h> -#include <sys/mman.h> -#include <unistd.h> -#include <string.h> -#include <stdbool.h> - +#include "lib.h" +#include "syscall.h" +#include "liburing.h" #include "liburing/compat.h" #include "liburing/io_uring.h" -#include "liburing.h" -#include "liburing/barrier.h" - -#include "syscall.h" /* * Returns true if we're not using SQ thread (thus nobody submits but us) diff --git a/src/register.c b/src/register.c index 074223f..1f2c409 100644 --- a/src/register.c +++ b/src/register.c @@ -1,18 +1,12 @@ /* SPDX-License-Identifier: MIT */ #define _POSIX_C_SOURCE 200112L -#include <sys/types.h> -#include <sys/stat.h> -#include <sys/mman.h> -#include <sys/resource.h> -#include <unistd.h> -#include <string.h> - +#include "lib.h" +#include "syscall.h" +#include "liburing.h" #include "liburing/compat.h" #include "liburing/io_uring.h" -#include "liburing.h" -#include "syscall.h" int io_uring_register_buffers_update_tag(struct io_uring *ring, unsigned off, const struct iovec *iovecs, diff --git a/src/setup.c b/src/setup.c index 4f006de..5543468 100644 --- a/src/setup.c +++ b/src/setup.c @@ -1,18 +1,12 @@ /* SPDX-License-Identifier: MIT */ #define _DEFAULT_SOURCE -#include <sys/types.h> -#include <sys/stat.h> -#include <unistd.h> -#include <string.h> -#include <stdlib.h> -#include <signal.h> - +#include "lib.h" +#include "syscall.h" +#include "liburing.h" #include "liburing/compat.h" #include "liburing/io_uring.h" -#include "liburing.h" -#include "syscall.h" static void io_uring_unmap_rings(struct io_uring_sq *sq, struct io_uring_cq *cq) { @@ -336,10 +330,7 @@ ssize_t io_uring_mlock_size_params(unsigned entries, struct io_uring_params *p) cq_entries = 2 * entries; } - page_size = sysconf(_SC_PAGESIZE); - if (page_size < 0) - page_size = 4096; - + page_size = get_page_size(); return rings_size(entries, cq_entries, page_size); } diff --git a/src/syscall.c b/src/syscall.c index 5923fbb..4e28e25 100644 --- a/src/syscall.c +++ b/src/syscall.c @@ -1,6 +1,16 @@ /* SPDX-License-Identifier: MIT */ #define _DEFAULT_SOURCE +/* + * Functions in this file require libc, only build them when we use libc. + * + * Note: + * liburing's tests still need these functions. + */ +#if defined(CONFIG_NOLIBC) && !defined(LIBURING_BUILD_TEST) +# error "This file should only be compiled for libc build, or for liburing tests" +#endif + /* * Will go away once libc support is there */ @@ -11,7 +21,6 @@ #include "liburing/io_uring.h" #include "syscall.h" - int __sys_io_uring_register(int fd, unsigned opcode, const void *arg, unsigned nr_args) { diff --git a/src/syscall.h b/src/syscall.h index 9eff968..4b336f1 100644 --- a/src/syscall.h +++ b/src/syscall.h @@ -29,13 +29,13 @@ # endif #elif defined __mips__ # ifndef __NR_io_uring_setup -# define __NR_io_uring_setup (__NR_Linux + 425) +# define __NR_io_uring_setup (__NR_Linux + 425) # endif # ifndef __NR_io_uring_enter -# define __NR_io_uring_enter (__NR_Linux + 426) +# define __NR_io_uring_enter (__NR_Linux + 426) # endif # ifndef __NR_io_uring_register -# define __NR_io_uring_register (__NR_Linux + 427) +# define __NR_io_uring_register (__NR_Linux + 427) # endif #else /* !__alpha__ and !__mips__ */ # ifndef __NR_io_uring_setup @@ -49,9 +49,22 @@ # endif #endif - +/* + * Don't put this below the #include "arch/$arch/syscall.h", that + * file may need it. + */ struct io_uring_params; + +#ifdef CONFIG_NOLIBC +# if defined(__x86_64__) || defined(__i386__) +# include "arch/x86/syscall.h" +# else +# error "This arch doesn't support building liburing without libc" +# endif +#endif + + /* * System calls */ @@ -68,12 +81,12 @@ static inline void *ERR_PTR(intptr_t n) return (void *) n; } -static inline intptr_t PTR_ERR(void *ptr) +static inline intptr_t PTR_ERR(const void *ptr) { return (intptr_t) ptr; } -static inline bool IS_ERR(void *ptr) +static inline bool IS_ERR(const void *ptr) { return uring_unlikely((uintptr_t) ptr >= (uintptr_t) -4095UL); } @@ -81,30 +94,40 @@ static inline bool IS_ERR(void *ptr) static inline int ____sys_io_uring_register(int fd, unsigned opcode, const void *arg, unsigned nr_args) { +#ifdef CONFIG_NOLIBC + return __arch_impl_io_uring_register(fd, opcode, arg, nr_args); +#else int ret; - ret = syscall(__NR_io_uring_register, fd, opcode, arg, nr_args); return (ret < 0) ? -errno : ret; +#endif } static inline int ____sys_io_uring_setup(unsigned entries, struct io_uring_params *p) { +#ifdef CONFIG_NOLIBC + return __arch_impl_io_uring_setup(entries, p); +#else int ret; - ret = syscall(__NR_io_uring_setup, entries, p); return (ret < 0) ? -errno : ret; +#endif } static inline int ____sys_io_uring_enter2(int fd, unsigned to_submit, unsigned min_complete, unsigned flags, sigset_t *sig, int sz) { +#ifdef CONFIG_NOLIBC + return __arch_impl_io_uring_enter(fd, to_submit, min_complete, flags, + sig, sz); +#else int ret; - ret = syscall(__NR_io_uring_enter, fd, to_submit, min_complete, flags, sig, sz); return (ret < 0) ? -errno : ret; +#endif } static inline int ____sys_io_uring_enter(int fd, unsigned to_submit, @@ -118,50 +141,68 @@ static inline int ____sys_io_uring_enter(int fd, unsigned to_submit, static inline void *uring_mmap(void *addr, size_t length, int prot, int flags, int fd, off_t offset) { +#ifdef CONFIG_NOLIBC + return __arch_impl_mmap(addr, length, prot, flags, fd, offset); +#else void *ret; - ret = mmap(addr, length, prot, flags, fd, offset); return (ret == MAP_FAILED) ? ERR_PTR(-errno) : ret; +#endif } static inline int uring_munmap(void *addr, size_t length) { +#ifdef CONFIG_NOLIBC + return __arch_impl_munmap(addr, length); +#else int ret; - ret = munmap(addr, length); return (ret < 0) ? -errno : ret; +#endif } static inline int uring_madvise(void *addr, size_t length, int advice) { +#ifdef CONFIG_NOLIBC + return __arch_impl_madvise(addr, length, advice); +#else int ret; - ret = madvise(addr, length, advice); return (ret < 0) ? -errno : ret; +#endif } static inline int uring_getrlimit(int resource, struct rlimit *rlim) { +#ifdef CONFIG_NOLIBC + return __arch_impl_getrlimit(resource, rlim); +#else int ret; - ret = getrlimit(resource, rlim); return (ret < 0) ? -errno : ret; +#endif } static inline int uring_setrlimit(int resource, const struct rlimit *rlim) { +#ifdef CONFIG_NOLIBC + return __arch_impl_setrlimit(resource, rlim); +#else int ret; - ret = setrlimit(resource, rlim); return (ret < 0) ? -errno : ret; +#endif } static inline int uring_close(int fd) { +#ifdef CONFIG_NOLIBC + return __arch_impl_close(fd); +#else int ret; - ret = close(fd); return (ret < 0) ? -errno : ret; +#endif } #endif diff --git a/test/Makefile b/test/Makefile index 2936469..1a10a24 100644 --- a/test/Makefile +++ b/test/Makefile @@ -21,8 +21,8 @@ ifdef CONFIG_HAVE_ARRAY_BOUNDS endif CXXFLAGS ?= $(CFLAGS) -override CFLAGS += $(XCFLAGS) -override CXXFLAGS += $(XCFLAGS) -std=c++11 +override CFLAGS += $(XCFLAGS) -DLIBURING_BUILD_TEST +override CXXFLAGS += $(XCFLAGS) -std=c++11 -DLIBURING_BUILD_TEST LDFLAGS ?= override LDFLAGS += -L../src/ -luring @@ -153,11 +153,22 @@ test_targets += sq-full-cpp endif all_targets += sq-full-cpp -helpers = helpers.o +# +# Build ../src/syscall.c manually from test's Makefile to support +# liburing nolibc. +# +# Functions in ../src/syscall.c require libc to work with, if we +# build liburing without libc, we don't have those functions +# in liburing.a. So build it manually here. +# +helpers = helpers.o ../src/syscall.o all: ${helpers} $(test_targets) -helpers.o: helpers.c helpers.c +../src/syscall.o: ../src/syscall.c + $(QUIET_CC)$(CC) $(CPPFLAGS) $(CFLAGS) -o $@ -c $< + +helpers.o: helpers.c $(QUIET_CC)$(CC) $(CPPFLAGS) $(CFLAGS) -o $@ -c $< %: %.c ${helpers} helpers.h -- 2.30.2
