* [PATCH v2 RFC liburing 1/5] test/{iopoll,read-write}: Use `io_uring_free_probe()` instead of `free()`
2021-10-07 6:31 ` [PATCHSET v2 RFC liburing 0/5] " Ammar Faizi
@ 2021-10-07 6:31 ` Ammar Faizi
2021-10-07 12:25 ` Jens Axboe
2021-10-07 6:31 ` [PATCH v2 RFC liburing 2/5] test/cq-size: Don't use `errno` to check liburing's functions Ammar Faizi
` (4 subsequent siblings)
5 siblings, 1 reply; 26+ messages in thread
From: Ammar Faizi @ 2021-10-07 6:31 UTC (permalink / raw)
To: Jens Axboe, Pavel Begunkov, io-uring Mailing List
Cc: Bedirhan KURT, Louvian Lyndal, Ammar Faizi
`io_uring_free_probe()` should really be used to free the return value
of `io_uring_get_probe_ring()`. As we may not always allocate it with
`malloc()`. For example, to support no libc build [1].
Link: https://github.com/axboe/liburing/issues/443 [1]
Signed-off-by: Ammar Faizi <[email protected]>
---
test/iopoll.c | 2 +-
test/read-write.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/test/iopoll.c b/test/iopoll.c
index de36473..4bfc26a 100644
--- a/test/iopoll.c
+++ b/test/iopoll.c
@@ -306,7 +306,7 @@ static int probe_buf_select(void)
fprintf(stdout, "Buffer select not supported, skipping\n");
return 0;
}
- free(p);
+ io_uring_free_probe(p);
return 0;
}
diff --git a/test/read-write.c b/test/read-write.c
index 885905b..d54ad0e 100644
--- a/test/read-write.c
+++ b/test/read-write.c
@@ -480,7 +480,7 @@ static int test_buf_select(const char *filename, int nonvec)
fprintf(stdout, "Buffer select not supported, skipping\n");
return 0;
}
- free(p);
+ io_uring_free_probe(p);
/*
* Write out data with known pattern
--
2.30.2
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH v2 RFC liburing 2/5] test/cq-size: Don't use `errno` to check liburing's functions
2021-10-07 6:31 ` [PATCHSET v2 RFC liburing 0/5] " Ammar Faizi
2021-10-07 6:31 ` [PATCH v2 RFC liburing 1/5] test/{iopoll,read-write}: Use `io_uring_free_probe()` instead of `free()` Ammar Faizi
@ 2021-10-07 6:31 ` Ammar Faizi
2021-10-07 12:25 ` Jens Axboe
2021-10-07 6:31 ` [PATCH v2 RFC liburing 3/5] Add arch dependent directory and files Ammar Faizi
` (3 subsequent siblings)
5 siblings, 1 reply; 26+ messages in thread
From: Ammar Faizi @ 2021-10-07 6:31 UTC (permalink / raw)
To: Jens Axboe, Pavel Begunkov, io-uring Mailing List
Cc: Bedirhan KURT, Louvian Lyndal, Ammar Faizi
When we build liburing without libc, we can't check `errno` variable
with respect to liburing's functions. Don't do that it in test.
Note:
The tests themselves can still use `errno` to check error from
functions that come from the libc, but not liburing.
Link: https://github.com/axboe/liburing/issues/443
Fixes: https://github.com/axboe/liburing/issues/449
Signed-off-by: Ammar Faizi <[email protected]>
---
test/cq-size.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/test/cq-size.c b/test/cq-size.c
index b7dd5b4..4e6e3d1 100644
--- a/test/cq-size.c
+++ b/test/cq-size.c
@@ -45,14 +45,20 @@ int main(int argc, char *argv[])
p.cq_entries = 0;
ret = io_uring_queue_init_params(4, &ring, &p);
- if (ret >= 0 || errno != EINVAL) {
+ if (ret >= 0) {
printf("zero sized cq ring succeeded\n");
+ io_uring_queue_exit(&ring);
+ goto err;
+ }
+
+ if (ret != -EINVAL) {
+ printf("io_uring_queue_init_params failed, but not with -EINVAL"
+ ", returned error %d (%s)\n", ret, strerror(-ret));
goto err;
}
done:
return 0;
err:
- io_uring_queue_exit(&ring);
return 1;
}
--
2.30.2
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH v2 RFC liburing 3/5] Add arch dependent directory and files
2021-10-07 6:31 ` [PATCHSET v2 RFC liburing 0/5] " Ammar Faizi
2021-10-07 6:31 ` [PATCH v2 RFC liburing 1/5] test/{iopoll,read-write}: Use `io_uring_free_probe()` instead of `free()` Ammar Faizi
2021-10-07 6:31 ` [PATCH v2 RFC liburing 2/5] test/cq-size: Don't use `errno` to check liburing's functions Ammar Faizi
@ 2021-10-07 6:31 ` Ammar Faizi
2021-10-07 6:31 ` [PATCH v2 RFC liburing 4/5] Add no libc build support Ammar Faizi
` (2 subsequent siblings)
5 siblings, 0 replies; 26+ messages in thread
From: Ammar Faizi @ 2021-10-07 6:31 UTC (permalink / raw)
To: Jens Axboe, Pavel Begunkov, io-uring Mailing List
Cc: Bedirhan KURT, Louvian Lyndal, Ammar Faizi
Create a new directory `src/arch` to save arch dependent sources.
Add support start from x86-64, add syscalls crafted in Assembly code
and lib (currently the lib only contains get page size function).
Link: https://github.com/axboe/liburing/issues/443
Signed-off-by: Ammar Faizi <[email protected]>
---
src/arch/x86/lib.h | 26 ++++++
src/arch/x86/syscall.h | 200 +++++++++++++++++++++++++++++++++++++++++
2 files changed, 226 insertions(+)
create mode 100644 src/arch/x86/lib.h
create mode 100644 src/arch/x86/syscall.h
diff --git a/src/arch/x86/lib.h b/src/arch/x86/lib.h
new file mode 100644
index 0000000..0d4b321
--- /dev/null
+++ b/src/arch/x86/lib.h
@@ -0,0 +1,26 @@
+/* SPDX-License-Identifier: MIT */
+
+#ifndef LIBURING_ARCH_X86_LIB_H
+#define LIBURING_ARCH_X86_LIB_H
+
+#ifndef LIBURING_LIB_H
+# error "This file should be included from src/lib.h (liburing)"
+#endif
+
+#if defined(__x86_64__)
+
+static inline long __arch_impl_get_page_size(void)
+{
+ return 4096;
+}
+
+#else /* #if defined(__x86_64__) */
+
+/*
+ * TODO: Add x86 (32-bit) support here.
+ */
+#error "x86 (32-bit) is currently not supported"
+
+#endif /* #if defined(__x86_64__) */
+
+#endif /* #ifndef LIBURING_ARCH_X86_LIB_H */
diff --git a/src/arch/x86/syscall.h b/src/arch/x86/syscall.h
new file mode 100644
index 0000000..be18165
--- /dev/null
+++ b/src/arch/x86/syscall.h
@@ -0,0 +1,200 @@
+/* SPDX-License-Identifier: MIT */
+
+#ifndef LIBURING_ARCH_X86_SYSCALL_H
+#define LIBURING_ARCH_X86_SYSCALL_H
+
+#ifndef LIBURING_SYSCALL_H
+# error "This file should be included from src/syscall.h (liburing)"
+#endif
+
+#if defined(__x86_64__)
+/**
+ * Note for syscall registers usage (x86-64):
+ * - %rax is the syscall number.
+ * - %rax is also the return value.
+ * - %rdi is the 1st argument.
+ * - %rsi is the 2nd argument.
+ * - %rdx is the 3rd argument.
+ * - %r10 is the 4th argument (**yes it's %r10, not %rcx!**).
+ * - %r8 is the 5th argument.
+ * - %r9 is the 6th argument.
+ *
+ * `syscall` instruction will clobber %r11 and %rcx.
+ *
+ * After the syscall returns to userspace:
+ * - %r11 will contain %rflags.
+ * - %rcx will contain the return address.
+ *
+ * IOW, after the syscall returns to userspace:
+ * %r11 == %rflags and %rcx == %rip.
+ */
+
+static inline void *__arch_impl_mmap(void *addr, size_t length, int prot,
+ int flags, int fd, off_t offset)
+{
+ void *rax;
+ register int r10 __asm__("r10") = flags;
+ register int r8 __asm__("r8") = fd;
+ register off_t r9 __asm__("r9") = offset;
+
+ __asm__ volatile(
+ "syscall"
+ : "=a"(rax)
+ : "a"(__NR_mmap), /* %rax */
+ "D"(addr), /* %rdi */
+ "S"(length), /* %rsi */
+ "d"(prot), /* %rdx */
+ "r"(r10), /* %r10 */
+ "r"(r8), /* %r8 */
+ "r"(r9) /* %r9 */
+ : "memory", "rcx", "r11"
+ );
+ return rax;
+}
+
+static inline int __arch_impl_munmap(void *addr, size_t length)
+{
+ long rax;
+
+ __asm__ volatile(
+ "syscall"
+ : "=a"(rax) /* %rax */
+ : "a"(__NR_munmap), /* %rax */
+ "D"(addr), /* %rdi */
+ "S"(length) /* %rsi */
+ : "memory", "rcx", "r11"
+ );
+ return (int) rax;
+}
+
+static inline int __arch_impl_madvise(void *addr, size_t length, int advice)
+{
+ long rax;
+
+ __asm__ volatile(
+ "syscall"
+ : "=a"(rax) /* %rax */
+ : "a"(__NR_madvise), /* %rax */
+ "D"(addr), /* %rdi */
+ "S"(length), /* %rsi */
+ "d"(advice) /* %rdx */
+ : "memory", "rcx", "r11"
+ );
+ return (int) rax;
+}
+
+static inline int __arch_impl_getrlimit(int resource, struct rlimit *rlim)
+{
+ long rax;
+
+ __asm__ volatile(
+ "syscall"
+ : "=a"(rax) /* %rax */
+ : "a"(__NR_getrlimit), /* %rax */
+ "D"(resource), /* %rdi */
+ "S"(rlim) /* %rsi */
+ : "memory", "rcx", "r11"
+ );
+ return (int) rax;
+}
+
+static inline int __arch_impl_setrlimit(int resource, const struct rlimit *rlim)
+{
+ long rax;
+
+ __asm__ volatile(
+ "syscall"
+ : "=a"(rax) /* %rax */
+ : "a"(__NR_setrlimit), /* %rax */
+ "D"(resource), /* %rdi */
+ "S"(rlim) /* %rsi */
+ : "memory", "rcx", "r11"
+ );
+ return (int) rax;
+}
+
+static inline int __arch_impl_close(int fd)
+{
+ long rax;
+
+ __asm__ volatile(
+ "syscall"
+ : "=a"(rax) /* %rax */
+ : "a"(__NR_close), /* %rax */
+ "D"(fd) /* %rdi */
+ : "memory", "rcx", "r11"
+ );
+ return (int) rax;
+}
+
+static inline int __arch_impl_io_uring_register(int fd, unsigned opcode,
+ const void *arg,
+ unsigned nr_args)
+{
+ long rax;
+ register unsigned r10 __asm__("r10") = nr_args;
+
+ __asm__ volatile(
+ "syscall"
+ : "=a"(rax) /* %rax */
+ : "a"(__NR_io_uring_register), /* %rax */
+ "D"(fd), /* %rdi */
+ "S"(opcode), /* %rsi */
+ "d"(arg), /* %rdx */
+ "r"(r10) /* %r10 */
+ : "memory", "rcx", "r11"
+ );
+ return (int) rax;
+}
+
+static inline int __arch_impl_io_uring_setup(unsigned entries,
+ struct io_uring_params *p)
+{
+ long rax;
+
+ __asm__ volatile(
+ "syscall"
+ : "=a"(rax) /* %rax */
+ : "a"(__NR_io_uring_setup), /* %rax */
+ "D"(entries), /* %rdi */
+ "S"(p) /* %rsi */
+ : "memory", "rcx", "r11"
+ );
+ return (int) rax;
+}
+
+static inline int __arch_impl_io_uring_enter(int fd, unsigned to_submit,
+ unsigned min_complete,
+ unsigned flags, sigset_t *sig,
+ int sz)
+{
+ long rax;
+ register unsigned r10 __asm__("r10") = flags;
+ register sigset_t *r8 __asm__("r8") = sig;
+ register int r9 __asm__("r9") = sz;
+
+ __asm__ volatile(
+ "syscall"
+ : "=a"(rax)
+ : "a"(__NR_io_uring_enter), /* %rax */
+ "D"(fd), /* %rdi */
+ "S"(to_submit), /* %rsi */
+ "d"(min_complete), /* %rdx */
+ "r"(r10), /* %r10 */
+ "r"(r8), /* %r8 */
+ "r"(r9) /* %r9 */
+ : "memory", "rcx", "r11"
+ );
+ return (int) rax;
+}
+
+#else /* #if defined(__x86_64__) */
+
+/*
+ * TODO: Add x86 (32-bit) support here.
+ */
+#error "x86 (32-bit) is currently not supported"
+
+#endif /* #if defined(__x86_64__) */
+
+#endif /* #ifndef LIBURING_ARCH_X86_SYSCALL_H */
--
2.30.2
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH v2 RFC liburing 4/5] Add no libc build support
2021-10-07 6:31 ` [PATCHSET v2 RFC liburing 0/5] " Ammar Faizi
` (2 preceding siblings ...)
2021-10-07 6:31 ` [PATCH v2 RFC liburing 3/5] Add arch dependent directory and files Ammar Faizi
@ 2021-10-07 6:31 ` Ammar Faizi
2021-10-07 12:27 ` Jens Axboe
2021-10-07 6:31 ` [PATCH v2 RFC liburing 5/5] Add LIBURING_NOLIBC variable and edit src/Makefile Ammar Faizi
2021-10-07 15:02 ` [PATCHSET liburing 0/4] Add no libc support for x86-64 arch Ammar Faizi
5 siblings, 1 reply; 26+ messages in thread
From: Ammar Faizi @ 2021-10-07 6:31 UTC (permalink / raw)
To: Jens Axboe, Pavel Begunkov, io-uring Mailing List
Cc: Bedirhan KURT, Louvian Lyndal, Ammar Faizi
Create `src/nolibc.c` to substitute libc functions like `memset()`,
`malloc()` and `free()`. Only build this file when we build liburing
without libc.
Wrap libc functions with `static inline` functions, defined in
`src/lib.h`, currently we have:
1) `get_page_size`
2) `uring_memset`
3) `uring_malloc`
4) `uring_free`
Add conditional preprocessor in `src/{syscall,lib}.h` to use arch
dependent and nolibc functions 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 test's Makefile.
The Makefile in `src/` dir still builds `src/syscall.c` when we
compile liburing with libc.
Link: https://github.com/axboe/liburing/issues/443
Signed-off-by: Ammar Faizi <[email protected]>
---
src/lib.h | 77 ++++++++++++++++++++++++++++++++++++++++++++++++++
src/nolibc.c | 48 +++++++++++++++++++++++++++++++
src/queue.c | 14 ++-------
src/register.c | 12 ++------
src/setup.c | 30 +++++++-------------
src/syscall.c | 11 +++++++-
src/syscall.h | 71 ++++++++++++++++++++++++++++++++++++----------
test/Makefile | 19 ++++++++++---
8 files changed, 222 insertions(+), 60 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..baacabe
--- /dev/null
+++ b/src/lib.h
@@ -0,0 +1,77 @@
+/* SPDX-License-Identifier: MIT */
+#ifndef LIBURING_LIB_H
+#define LIBURING_LIB_H
+
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#ifdef LIBURING_NOLIBC
+# if defined(__x86_64__) || defined(__i386__)
+# include "arch/x86/lib.h"
+# else
+# error "The arch is currently not supported to build 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 LIBURING_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
+}
+
+void *__uring_memset(void *s, int c, size_t n);
+
+static inline void *uring_memset(void *s, int c, size_t n)
+{
+#ifdef LIBURING_NOLIBC
+ return __uring_memset(s, c, n);
+#else
+ return memset(s, c, n);
+#endif
+}
+
+void *__uring_malloc(size_t len);
+
+static inline void *uring_malloc(size_t len)
+{
+#ifdef LIBURING_NOLIBC
+ return __uring_malloc(len);
+#else
+ return malloc(len);
+#endif
+}
+
+void __uring_free(void *p);
+
+static inline void uring_free(void *p)
+{
+#ifdef LIBURING_NOLIBC
+ __uring_free(p);
+#else
+ free(p);
+#endif
+}
+
+#endif /* #ifndef LIBURING_LIB_H */
diff --git a/src/nolibc.c b/src/nolibc.c
new file mode 100644
index 0000000..149426c
--- /dev/null
+++ b/src/nolibc.c
@@ -0,0 +1,48 @@
+/* SPDX-License-Identifier: MIT */
+
+#ifndef LIBURING_NOLIBC
+# error "This file should only be compiled for no libc build"
+#endif
+
+#include "lib.h"
+#include "syscall.h"
+
+void *__uring_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 *__uring_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 __uring_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..700dc07 100644
--- a/src/setup.c
+++ b/src/setup.c
@@ -1,18 +1,11 @@
/* 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)
{
@@ -93,7 +86,7 @@ int io_uring_queue_mmap(int fd, struct io_uring_params *p, struct io_uring *ring
{
int ret;
- memset(ring, 0, sizeof(*ring));
+ uring_memset(ring, 0, sizeof(*ring));
ret = io_uring_mmap(fd, p, &ring->sq, &ring->cq);
if (!ret) {
ring->flags = p->flags;
@@ -161,7 +154,7 @@ int io_uring_queue_init(unsigned entries, struct io_uring *ring, unsigned flags)
{
struct io_uring_params p;
- memset(&p, 0, sizeof(p));
+ uring_memset(&p, 0, sizeof(p));
p.flags = flags;
return io_uring_queue_init_params(entries, ring, &p);
@@ -184,16 +177,16 @@ struct io_uring_probe *io_uring_get_probe_ring(struct io_uring *ring)
int r;
len = sizeof(*probe) + 256 * sizeof(struct io_uring_probe_op);
- probe = malloc(len);
+ probe = uring_malloc(len);
if (!probe)
return NULL;
- memset(probe, 0, len);
+ uring_memset(probe, 0, len);
r = io_uring_register_probe(ring, probe, 256);
if (r >= 0)
return probe;
- free(probe);
+ uring_free(probe);
return NULL;
}
@@ -214,7 +207,7 @@ struct io_uring_probe *io_uring_get_probe(void)
void io_uring_free_probe(struct io_uring_probe *probe)
{
- free(probe);
+ uring_free(probe);
}
static int __fls(int x)
@@ -336,10 +329,7 @@ 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..cfb3ee2 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(LIBURING_NOLIBC) && !defined(LIBURING_BUILD_TEST)
+# error "This file should only be compiled for libc build"
+#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..82f5db0 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 LIBURING_NOLIBC
+# if defined(__x86_64__) || defined(__i386__)
+# include "arch/x86/syscall.h"
+# else
+# error "The arch is currently not supported to build 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 LIBURING_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 LIBURING_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 LIBURING_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 LIBURING_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 LIBURING_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 LIBURING_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 LIBURING_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 LIBURING_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 LIBURING_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
^ permalink raw reply related [flat|nested] 26+ messages in thread
* Re: [PATCH v2 RFC liburing 4/5] Add no libc build support
2021-10-07 6:31 ` [PATCH v2 RFC liburing 4/5] Add no libc build support Ammar Faizi
@ 2021-10-07 12:27 ` Jens Axboe
2021-10-07 13:01 ` Ammar Faizi
0 siblings, 1 reply; 26+ messages in thread
From: Jens Axboe @ 2021-10-07 12:27 UTC (permalink / raw)
To: Ammar Faizi, Pavel Begunkov, io-uring Mailing List
Cc: Bedirhan KURT, Louvian Lyndal
On 10/7/21 12:31 AM, Ammar Faizi wrote:
> Create `src/nolibc.c` to substitute libc functions like `memset()`,
> `malloc()` and `free()`. Only build this file when we build liburing
> without libc.
>
> Wrap libc functions with `static inline` functions, defined in
> `src/lib.h`, currently we have:
> 1) `get_page_size`
> 2) `uring_memset`
> 3) `uring_malloc`
> 4) `uring_free`
>
> Add conditional preprocessor in `src/{syscall,lib}.h` to use arch
> dependent and nolibc functions 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 test's Makefile.
>
> The Makefile in `src/` dir still builds `src/syscall.c` when we
> compile liburing with libc.
Why are we jumping through hoops on the naming? You add a uring_memset()
that the lib is supposed to use, then that calls memset() with libc or
__uring_memset() if we're building without libc. Why not just have the
nolibc build provide memset() and avoids this churn? Not just in terms
of the immediate patch, that matters less. But longer term where
inevitably a memset() or similar will be added to the existing code
base.
--
Jens Axboe
^ permalink raw reply [flat|nested] 26+ messages in thread
* Re: [PATCH v2 RFC liburing 4/5] Add no libc build support
2021-10-07 12:27 ` Jens Axboe
@ 2021-10-07 13:01 ` Ammar Faizi
0 siblings, 0 replies; 26+ messages in thread
From: Ammar Faizi @ 2021-10-07 13:01 UTC (permalink / raw)
To: Jens Axboe, Pavel Begunkov, io-uring Mailing List
Cc: Bedirhan KURT, Louvian Lyndal
On Thu, Oct 7, 2021 at 7:27 PM Jens Axboe <[email protected]> wrote:
>
> On 10/7/21 12:31 AM, Ammar Faizi wrote:
> > Create `src/nolibc.c` to substitute libc functions like `memset()`,
> > `malloc()` and `free()`. Only build this file when we build liburing
> > without libc.
> >
> > Wrap libc functions with `static inline` functions, defined in
> > `src/lib.h`, currently we have:
> > 1) `get_page_size`
> > 2) `uring_memset`
> > 3) `uring_malloc`
> > 4) `uring_free`
> >
> > Add conditional preprocessor in `src/{syscall,lib}.h` to use arch
> > dependent and nolibc functions 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 test's Makefile.
> >
> > The Makefile in `src/` dir still builds `src/syscall.c` when we
> > compile liburing with libc.
>
> Why are we jumping through hoops on the naming? You add a uring_memset()
> that the lib is supposed to use, then that calls memset() with libc or
> __uring_memset() if we're building without libc. Why not just have the
> nolibc build provide memset() and avoids this churn? Not just in terms
> of the immediate patch, that matters less. But longer term where
> inevitably a memset() or similar will be added to the existing code
> base.
>
Ah, good point. The syscall wrappers gave me this bad suggestion. I know
we have a rationale to wrap syscalls because we need to eliminate `errno`
being used in C files. But we don't actually need extra wrappers for
`memset()`, `malloc()` and `free()`.
I agree that we can just provide `memset()`, `malloc()` and `free()` for
the nolibc build without having extra wrappers like that.
I will address this and send the rest as a PATCHSET.
--
Ammar Faizi
^ permalink raw reply [flat|nested] 26+ messages in thread
* [PATCH v2 RFC liburing 5/5] Add LIBURING_NOLIBC variable and edit src/Makefile
2021-10-07 6:31 ` [PATCHSET v2 RFC liburing 0/5] " Ammar Faizi
` (3 preceding siblings ...)
2021-10-07 6:31 ` [PATCH v2 RFC liburing 4/5] Add no libc build support Ammar Faizi
@ 2021-10-07 6:31 ` Ammar Faizi
2021-10-07 15:02 ` [PATCHSET liburing 0/4] Add no libc support for x86-64 arch Ammar Faizi
5 siblings, 0 replies; 26+ messages in thread
From: Ammar Faizi @ 2021-10-07 6:31 UTC (permalink / raw)
To: Jens Axboe, Pavel Begunkov, io-uring Mailing List
Cc: Bedirhan KURT, Louvian Lyndal, Ammar Faizi
Conditonal variable to enable nolibc build.
Link: https://github.com/axboe/liburing/issues/443
Signed-off-by: Ammar Faizi <[email protected]>
---
configure | 7 +++++++
src/Makefile | 13 ++++++++++++-
2 files changed, 19 insertions(+), 1 deletion(-)
diff --git a/configure b/configure
index 92f51bd..6bdcead 100755
--- a/configure
+++ b/configure
@@ -358,6 +358,13 @@ print_config "has_memfd_create" "$has_memfd_create"
#############################################################################
+if test "$LIBURING_NOLIBC" = "y" -o "$LIBURING_NOLIBC" = "yes" -o "$LIBURING_NOLIBC" = "1"; then
+ output_sym "LIBURING_NOLIBC"
+ LIBURING_NOLIBC="yes"
+else
+ LIBURING_NOLIBC="no"
+fi
+print_config "LIBURING_NOLIBC" "$LIBURING_NOLIBC"
if test "$__kernel_rwf_t" = "yes"; then
output_sym "CONFIG_HAVE_KERNEL_RWF_T"
diff --git a/src/Makefile b/src/Makefile
index 5e46a9d..bc42675 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -32,11 +32,22 @@ endif
all: $(all_targets)
-liburing_srcs := setup.c queue.c syscall.c register.c
+liburing_srcs := setup.c queue.c register.c
+
+ifeq ($(LIBURING_NOLIBC),y)
+ liburing_srcs += nolibc.c
+ override CFLAGS += -nostdlib -nolibc -nodefaultlibs -ffreestanding -fno-stack-protector -fpic
+ override CPPFLAGS += -nostdlib -nolibc -nodefaultlibs -ffreestanding -fno-stack-protector -fpic
+ override LINK_FLAGS += -nostdlib -nolibc -nodefaultlibs -fpic
+else
+ liburing_srcs += syscall.c
+endif
liburing_objs := $(patsubst %.c,%.ol,$(liburing_srcs))
liburing_sobjs := $(patsubst %.c,%.os,$(liburing_srcs))
+$(liburing_srcs): syscall.h lib.h
+
$(liburing_objs) $(liburing_sobjs): include/liburing/io_uring.h
%.os: %.c
--
2.30.2
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCHSET liburing 0/4] Add no libc support for x86-64 arch
2021-10-07 6:31 ` [PATCHSET v2 RFC liburing 0/5] " Ammar Faizi
` (4 preceding siblings ...)
2021-10-07 6:31 ` [PATCH v2 RFC liburing 5/5] Add LIBURING_NOLIBC variable and edit src/Makefile Ammar Faizi
@ 2021-10-07 15:02 ` Ammar Faizi
2021-10-07 15:02 ` [PATCH liburing 1/4] test/thread-exit: Fix use after free bug Ammar Faizi
` (3 more replies)
5 siblings, 4 replies; 26+ messages in thread
From: Ammar Faizi @ 2021-10-07 15:02 UTC (permalink / raw)
To: Jens Axboe, Pavel Begunkov, io-uring Mailing List
Cc: Bedirhan KURT, Louvian Lyndal
Hi everyone,
This is a patchset after 2 RFC to support build liburing without libc.
In this patchset, I introduce no libc support for x86-64 arch.
Hopefully, one day we can get support for other architectures as well.
Motivation:
Currently liburing depends on libc. We want to make liburing can be
built without libc.
This idea firstly posted as an issue on the liburing GitHub
repository here: https://github.com/axboe/liburing/issues/443
The subject of the issue is: "An option to use liburing without libc?".
On Mon, Sep 27, 2021 at 4:18 PM Mahdi Rakhshandehroo <[email protected]> wrote:
> There are a couple of issues with liburing's libc dependency:
>
> 1) libc implementations of errno, malloc, pthread etc. tend to
> pollute the binary with unwanted global/thread-local state.
> This makes reentrancy impossible and relocations expensive.
> 2) libc doesn't play nice with non-POSIX threading models, like
> green threads with small stack sizes, or direct use of the
> clone() system call. This makes interop with other
> languages/runtimes difficult.
>
> One could use the raw syscall interface to io_uring to address these
> concerns, but that would be somewhat painful, so it would be nice
> for liburing to support this use case out of the box. Perhaps
> something like a NOLIBC macro could be added which, if defined,
> would patch out libc constructs and replace them with non-libc
> wrappers where applicable. A few API changes might be necessary for
> the non-libc case (e.g. io_uring_get_probe/io_uring_free_probe), but
> it shouldn't break existing applications as long as it's opt-in.
----------------------------------------------------------------
Explanation about the changes:
- New directory for arch dependent files. We create a new directory
`src/arch`. This is where the arch dependent sources live. Currently
we only have single arch support `src/arch/x86`. This directory
contains crafted syscalls written in inline Assembly and get page
size function.
- Currently, liburing uses 4 libc functions, they are:
1) `malloc`
2) `free`
3) `memset`
4) `sysconf` (to get the page size).
To support nolibc build, we provide our own functions in `src/nolibc.c`.
- Procedure to free the return value of `io_uring_get_probe_{,ring}`.
Currently, several tests use `free()` to free the return value of
this *probe* functions. But since these changes we should always
use `io_uring_free_probe()`. Don't use `free()`.
- Don't use `errno` to check error from liburing functions on tests.
We want the tests still work properly with liburing no libc.
----------------------------------------------------------------
How to build liburing without libc?
You can just simply add `export LIBURING_NOLIBC=y` before run the
build. Be sure to run `make clean` if you have dirty build, just to
ensure consistency.
ammarfaizi2@integral:~/project/now/liburing$ export LIBURING_NOLIBC=y
ammarfaizi2@integral:~/project/now/liburing$ ./configure
prefix /usr
includedir /usr/include
libdir /usr/lib
libdevdir /usr/lib
relativelibdir
mandir /usr/man
datadir /usr/share
stringop_overflow yes
array_bounds yes
__kernel_rwf_t yes
__kernel_timespec yes
open_how no
statx yes
C++ yes
has_ucontext yes
has_memfd_create yes
LIBURING_NOLIBC yes
CC gcc
CXX g++
ammarfaizi2@integral:~/project/now/liburing$ taskset -c 0,1,2,3 make -j4
Make sure you see the `LIBURING_NOLIBC` with `yes`.
----------------------------------------------------------------
Extra improvements of using liburing build without libc:
1) The file size of liburing.so is reduced.
With libc:
186906 src/liburing.a
116136 src/liburing.so.2.1.0
303042 total
Without libc:
168152 src/liburing.a
104136 src/liburing.so.2.1.0
272288 total
2) Efficient function call. We inline all `syscall` instructions with
inline Assembly. This greatly reduces the data movement, as syscall
only clobbers %rax, %rcx and %r11. Plus it is compatible with the
kernel style return value, so no need a branch to catch error from
`errno` variable anymore.
With libc, we may spend more extra time to save caller saved
registers just to perform a syscall, because if we use libc, every
syscall is wrapped with a function call.
Another extra thing is when we need to check `errno` variable, that
will cost more extra call to `__errno_location` and extra branches
(as per we implement the kernel style return value).
Without libc, the generated Assembly code is also smaller. For
example, we can take a look at this generated Assembly code of
`__io_uring_sqring_wait` function.
With libc:
0000000000003340 <__io_uring_sqring_wait>:
3340: f3 0f 1e fa endbr64
3344: 48 83 ec 10 sub $0x10,%rsp
3348: 8b b7 c4 00 00 00 mov 0xc4(%rdi),%esi
334e: 31 c9 xor %ecx,%ecx
3350: 31 d2 xor %edx,%edx
3352: 6a 08 push $0x8
3354: 41 b8 04 00 00 00 mov $0x4,%r8d
335a: 45 31 c9 xor %r9d,%r9d
335d: bf aa 01 00 00 mov $0x1aa,%edi
3362: 31 c0 xor %eax,%eax
3364: e8 17 ef ff ff call 2280 <syscall@plt>
3369: 5a pop %rdx
336a: 59 pop %rcx
336b: 41 89 c0 mov %eax,%r8d
336e: 85 c0 test %eax,%eax
3370: 79 0b jns 337d <__io_uring_sqring_wait+0x3d>
3372: e8 49 ee ff ff call 21c0 <__errno_location@plt>
3377: 44 8b 00 mov (%rax),%r8d
337a: 41 f7 d8 neg %r8d
337d: 44 89 c0 mov %r8d,%eax
3380: 48 83 c4 08 add $0x8,%rsp
3384: c3 ret
3385: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1)
338c: 00 00 00
338f: 90 nop
Without libc:
0000000000001e20 <__io_uring_sqring_wait>:
1e20: f3 0f 1e fa endbr64
1e24: 31 d2 xor %edx,%edx
1e26: 8b bf c4 00 00 00 mov 0xc4(%rdi),%edi
1e2c: 45 31 c0 xor %r8d,%r8d
1e2f: b8 aa 01 00 00 mov $0x1aa,%eax
1e34: 41 ba 04 00 00 00 mov $0x4,%r10d
1e3a: 41 b9 08 00 00 00 mov $0x8,%r9d
1e40: 89 d6 mov %edx,%esi
1e42: 0f 05 syscall
1e44: c3 ret
3) More portable shared library. Sometimes we meet a case where libc
version is not compatible with other versions of libc.
Now, as we do not depend on libc, it's easier to distribute the
liburing.so without worrying about libc version anymore. As long as
the architecture is the same and the kernel version is compatible,
that should not be a problem.
----------------------------------------------------------------
This patchset:
- Drop extra wrappers for `malloc()`, `free()` and `memset()`.
- Fix UAF bug in test/thread-exit. I found this after I changed the
function name `uring_free()` to `free()` for nolibc build.
- 2 patches have been applied in RFC v2, drop them. Add one extra
patch to fix the UAF bug. So we have 4 patches here.
RFC v2:
- Rebase the work based on commit 326ed975d49e8c7b ("configure: add
openat2.h for open_how and RESOLVE_* flags").
- Fix the patches order, make sure fix up the tests first, add
nolibc sources, and then add a variable build to enable it.
- Fix incorrect data type for `__arch_impl_mmap()` offset. It was
`int` (that's not right). The proper data type is `off_t`.
- Always use `long` or `void *` to contain the return value of
syscall in `__arch_impl_*` functions.
- Rename `src/no_libc.` to `src/nolibc.c`.
- Reduce the number of patches to 5, it was 6.
Link: [RFC v1] https://lore.kernel.org/io-uring/[email protected]/T/
Link: [RFC v2] https://lore.kernel.org/io-uring/[email protected]/
----------------------------------------------------------------
Ammar Faizi (4):
test/thread-exit: Fix use after free bug
Add arch dependent directory and files
Add no libc build support
Add LIBURING_NOLIBC variable and edit src/Makefile
configure | 7 ++
src/Makefile | 13 ++-
src/arch/x86/lib.h | 26 ++++++
src/arch/x86/syscall.h | 200 +++++++++++++++++++++++++++++++++++++++++++
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 +++-
test/thread-exit.c | 16 +++-
13 files changed, 442 insertions(+), 56 deletions(-)
create mode 100644 src/arch/x86/lib.h
create mode 100644 src/arch/x86/syscall.h
create mode 100644 src/lib.h
create mode 100644 src/nolibc.c
--
Ammar Faizi
^ permalink raw reply [flat|nested] 26+ messages in thread
* [PATCH liburing 1/4] test/thread-exit: Fix use after free bug
2021-10-07 15:02 ` [PATCHSET liburing 0/4] Add no libc support for x86-64 arch Ammar Faizi
@ 2021-10-07 15:02 ` Ammar Faizi
2021-10-07 15:02 ` [PATCH liburing 2/4] Add arch dependent directory and files Ammar Faizi
` (2 subsequent siblings)
3 siblings, 0 replies; 26+ messages in thread
From: Ammar Faizi @ 2021-10-07 15:02 UTC (permalink / raw)
To: Jens Axboe, Pavel Begunkov, io-uring Mailing List
Cc: Bedirhan KURT, Louvian Lyndal, Ammar Faizi
When I added support for nolibc x86-64, I found this test failed.
Long story short, we provide our own `free()` that always unmaps the VM
with `munmap()`. It makes the CQE return -EFAULT because the kernel
reads unmapped user memory from the pending `write()` SQE.
I believe this test can run properly with libc build because `free()`
from libc doesn't always unmap the memory, instead it uses free list on
the userspace and the freed heap may still be userspace addressable.
Fix this by deferring the free.
Cc: Jens Axboe <[email protected]>
Fixes: 2edfa3f84bcc44612b7a04caf1f048f5406fcc7a ("Add test case for thread exiting with pending IO")
Signed-off-by: Ammar Faizi <[email protected]>
---
test/thread-exit.c | 16 ++++++++++++++--
1 file changed, 14 insertions(+), 2 deletions(-)
diff --git a/test/thread-exit.c b/test/thread-exit.c
index 7f66028..05509fb 100644
--- a/test/thread-exit.c
+++ b/test/thread-exit.c
@@ -26,8 +26,18 @@ struct d {
unsigned long off;
int pipe_fd;
int err;
+ int i;
};
+char *g_buf[NR_IOS] = {NULL};
+
+static void free_g_buf(void)
+{
+ int i;
+ for (i = 0; i < NR_IOS; i++)
+ free(g_buf[i]);
+}
+
static void *do_io(void *data)
{
struct d *d = data;
@@ -36,6 +46,7 @@ static void *do_io(void *data)
int ret;
buffer = t_malloc(WSIZE);
+ g_buf[d->i] = buffer;
memset(buffer, 0x5a, WSIZE);
sqe = io_uring_get_sqe(d->ring);
if (!sqe) {
@@ -55,8 +66,6 @@ static void *do_io(void *data)
ret = io_uring_submit(d->ring);
if (ret != 2)
d->err++;
-
- free(buffer);
return NULL;
}
@@ -103,6 +112,7 @@ int main(int argc, char *argv[])
d.pipe_fd = fds[0];
d.err = 0;
for (i = 0; i < NR_IOS; i++) {
+ d.i = i;
memset(&thread, 0, sizeof(thread));
pthread_create(&thread, NULL, do_io, &d);
pthread_join(thread, NULL);
@@ -125,7 +135,9 @@ int main(int argc, char *argv[])
io_uring_cqe_seen(&ring, cqe);
}
+ free_g_buf();
return d.err;
err:
+ free_g_buf();
return 1;
}
--
2.30.2
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH liburing 2/4] Add arch dependent directory and files
2021-10-07 15:02 ` [PATCHSET liburing 0/4] Add no libc support for x86-64 arch Ammar Faizi
2021-10-07 15:02 ` [PATCH liburing 1/4] test/thread-exit: Fix use after free bug Ammar Faizi
@ 2021-10-07 15:02 ` Ammar Faizi
2021-10-07 15:02 ` [PATCH liburing 3/4] Add no libc build support Ammar Faizi
2021-10-07 15:02 ` [PATCH liburing 4/4] Add LIBURING_NOLIBC variable and edit src/Makefile Ammar Faizi
3 siblings, 0 replies; 26+ messages in thread
From: Ammar Faizi @ 2021-10-07 15:02 UTC (permalink / raw)
To: Jens Axboe, Pavel Begunkov, io-uring Mailing List
Cc: Bedirhan KURT, Louvian Lyndal, Ammar Faizi
Create a new directory `src/arch` to save arch dependent sources.
Add support start from x86-64, add syscalls crafted in Assembly code
and lib (currently the lib only contains get page size function).
Link: https://github.com/axboe/liburing/issues/443
Signed-off-by: Ammar Faizi <[email protected]>
---
src/arch/x86/lib.h | 26 ++++++
src/arch/x86/syscall.h | 200 +++++++++++++++++++++++++++++++++++++++++
2 files changed, 226 insertions(+)
create mode 100644 src/arch/x86/lib.h
create mode 100644 src/arch/x86/syscall.h
diff --git a/src/arch/x86/lib.h b/src/arch/x86/lib.h
new file mode 100644
index 0000000..0d4b321
--- /dev/null
+++ b/src/arch/x86/lib.h
@@ -0,0 +1,26 @@
+/* SPDX-License-Identifier: MIT */
+
+#ifndef LIBURING_ARCH_X86_LIB_H
+#define LIBURING_ARCH_X86_LIB_H
+
+#ifndef LIBURING_LIB_H
+# error "This file should be included from src/lib.h (liburing)"
+#endif
+
+#if defined(__x86_64__)
+
+static inline long __arch_impl_get_page_size(void)
+{
+ return 4096;
+}
+
+#else /* #if defined(__x86_64__) */
+
+/*
+ * TODO: Add x86 (32-bit) support here.
+ */
+#error "x86 (32-bit) is currently not supported"
+
+#endif /* #if defined(__x86_64__) */
+
+#endif /* #ifndef LIBURING_ARCH_X86_LIB_H */
diff --git a/src/arch/x86/syscall.h b/src/arch/x86/syscall.h
new file mode 100644
index 0000000..be18165
--- /dev/null
+++ b/src/arch/x86/syscall.h
@@ -0,0 +1,200 @@
+/* SPDX-License-Identifier: MIT */
+
+#ifndef LIBURING_ARCH_X86_SYSCALL_H
+#define LIBURING_ARCH_X86_SYSCALL_H
+
+#ifndef LIBURING_SYSCALL_H
+# error "This file should be included from src/syscall.h (liburing)"
+#endif
+
+#if defined(__x86_64__)
+/**
+ * Note for syscall registers usage (x86-64):
+ * - %rax is the syscall number.
+ * - %rax is also the return value.
+ * - %rdi is the 1st argument.
+ * - %rsi is the 2nd argument.
+ * - %rdx is the 3rd argument.
+ * - %r10 is the 4th argument (**yes it's %r10, not %rcx!**).
+ * - %r8 is the 5th argument.
+ * - %r9 is the 6th argument.
+ *
+ * `syscall` instruction will clobber %r11 and %rcx.
+ *
+ * After the syscall returns to userspace:
+ * - %r11 will contain %rflags.
+ * - %rcx will contain the return address.
+ *
+ * IOW, after the syscall returns to userspace:
+ * %r11 == %rflags and %rcx == %rip.
+ */
+
+static inline void *__arch_impl_mmap(void *addr, size_t length, int prot,
+ int flags, int fd, off_t offset)
+{
+ void *rax;
+ register int r10 __asm__("r10") = flags;
+ register int r8 __asm__("r8") = fd;
+ register off_t r9 __asm__("r9") = offset;
+
+ __asm__ volatile(
+ "syscall"
+ : "=a"(rax)
+ : "a"(__NR_mmap), /* %rax */
+ "D"(addr), /* %rdi */
+ "S"(length), /* %rsi */
+ "d"(prot), /* %rdx */
+ "r"(r10), /* %r10 */
+ "r"(r8), /* %r8 */
+ "r"(r9) /* %r9 */
+ : "memory", "rcx", "r11"
+ );
+ return rax;
+}
+
+static inline int __arch_impl_munmap(void *addr, size_t length)
+{
+ long rax;
+
+ __asm__ volatile(
+ "syscall"
+ : "=a"(rax) /* %rax */
+ : "a"(__NR_munmap), /* %rax */
+ "D"(addr), /* %rdi */
+ "S"(length) /* %rsi */
+ : "memory", "rcx", "r11"
+ );
+ return (int) rax;
+}
+
+static inline int __arch_impl_madvise(void *addr, size_t length, int advice)
+{
+ long rax;
+
+ __asm__ volatile(
+ "syscall"
+ : "=a"(rax) /* %rax */
+ : "a"(__NR_madvise), /* %rax */
+ "D"(addr), /* %rdi */
+ "S"(length), /* %rsi */
+ "d"(advice) /* %rdx */
+ : "memory", "rcx", "r11"
+ );
+ return (int) rax;
+}
+
+static inline int __arch_impl_getrlimit(int resource, struct rlimit *rlim)
+{
+ long rax;
+
+ __asm__ volatile(
+ "syscall"
+ : "=a"(rax) /* %rax */
+ : "a"(__NR_getrlimit), /* %rax */
+ "D"(resource), /* %rdi */
+ "S"(rlim) /* %rsi */
+ : "memory", "rcx", "r11"
+ );
+ return (int) rax;
+}
+
+static inline int __arch_impl_setrlimit(int resource, const struct rlimit *rlim)
+{
+ long rax;
+
+ __asm__ volatile(
+ "syscall"
+ : "=a"(rax) /* %rax */
+ : "a"(__NR_setrlimit), /* %rax */
+ "D"(resource), /* %rdi */
+ "S"(rlim) /* %rsi */
+ : "memory", "rcx", "r11"
+ );
+ return (int) rax;
+}
+
+static inline int __arch_impl_close(int fd)
+{
+ long rax;
+
+ __asm__ volatile(
+ "syscall"
+ : "=a"(rax) /* %rax */
+ : "a"(__NR_close), /* %rax */
+ "D"(fd) /* %rdi */
+ : "memory", "rcx", "r11"
+ );
+ return (int) rax;
+}
+
+static inline int __arch_impl_io_uring_register(int fd, unsigned opcode,
+ const void *arg,
+ unsigned nr_args)
+{
+ long rax;
+ register unsigned r10 __asm__("r10") = nr_args;
+
+ __asm__ volatile(
+ "syscall"
+ : "=a"(rax) /* %rax */
+ : "a"(__NR_io_uring_register), /* %rax */
+ "D"(fd), /* %rdi */
+ "S"(opcode), /* %rsi */
+ "d"(arg), /* %rdx */
+ "r"(r10) /* %r10 */
+ : "memory", "rcx", "r11"
+ );
+ return (int) rax;
+}
+
+static inline int __arch_impl_io_uring_setup(unsigned entries,
+ struct io_uring_params *p)
+{
+ long rax;
+
+ __asm__ volatile(
+ "syscall"
+ : "=a"(rax) /* %rax */
+ : "a"(__NR_io_uring_setup), /* %rax */
+ "D"(entries), /* %rdi */
+ "S"(p) /* %rsi */
+ : "memory", "rcx", "r11"
+ );
+ return (int) rax;
+}
+
+static inline int __arch_impl_io_uring_enter(int fd, unsigned to_submit,
+ unsigned min_complete,
+ unsigned flags, sigset_t *sig,
+ int sz)
+{
+ long rax;
+ register unsigned r10 __asm__("r10") = flags;
+ register sigset_t *r8 __asm__("r8") = sig;
+ register int r9 __asm__("r9") = sz;
+
+ __asm__ volatile(
+ "syscall"
+ : "=a"(rax)
+ : "a"(__NR_io_uring_enter), /* %rax */
+ "D"(fd), /* %rdi */
+ "S"(to_submit), /* %rsi */
+ "d"(min_complete), /* %rdx */
+ "r"(r10), /* %r10 */
+ "r"(r8), /* %r8 */
+ "r"(r9) /* %r9 */
+ : "memory", "rcx", "r11"
+ );
+ return (int) rax;
+}
+
+#else /* #if defined(__x86_64__) */
+
+/*
+ * TODO: Add x86 (32-bit) support here.
+ */
+#error "x86 (32-bit) is currently not supported"
+
+#endif /* #if defined(__x86_64__) */
+
+#endif /* #ifndef LIBURING_ARCH_X86_SYSCALL_H */
--
2.30.2
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH liburing 3/4] Add no libc build support
2021-10-07 15:02 ` [PATCHSET liburing 0/4] Add no libc support for x86-64 arch Ammar Faizi
2021-10-07 15:02 ` [PATCH liburing 1/4] test/thread-exit: Fix use after free bug Ammar Faizi
2021-10-07 15:02 ` [PATCH liburing 2/4] Add arch dependent directory and files Ammar Faizi
@ 2021-10-07 15:02 ` Ammar Faizi
2021-10-07 15:02 ` [PATCH liburing 4/4] Add LIBURING_NOLIBC variable and edit src/Makefile Ammar Faizi
3 siblings, 0 replies; 26+ messages in thread
From: Ammar Faizi @ 2021-10-07 15:02 UTC (permalink / raw)
To: Jens Axboe, Pavel Begunkov, io-uring Mailing List
Cc: Bedirhan KURT, Louvian Lyndal, Ammar Faizi
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
Signed-off-by: Ammar Faizi <[email protected]>
---
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..4c147f5
--- /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 LIBURING_NOLIBC
+# if defined(__x86_64__) || defined(__i386__)
+# include "arch/x86/lib.h"
+# else
+# error "The arch is currently not supported to build 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 LIBURING_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..cdf0e04
--- /dev/null
+++ b/src/nolibc.c
@@ -0,0 +1,48 @@
+/* SPDX-License-Identifier: MIT */
+
+#ifndef LIBURING_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..cfb3ee2 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(LIBURING_NOLIBC) && !defined(LIBURING_BUILD_TEST)
+# error "This file should only be compiled for libc build"
+#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..82f5db0 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 LIBURING_NOLIBC
+# if defined(__x86_64__) || defined(__i386__)
+# include "arch/x86/syscall.h"
+# else
+# error "The arch is currently not supported to build 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 LIBURING_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 LIBURING_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 LIBURING_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 LIBURING_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 LIBURING_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 LIBURING_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 LIBURING_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 LIBURING_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 LIBURING_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 ${helpers} helpers.h
--
2.30.2
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH liburing 4/4] Add LIBURING_NOLIBC variable and edit src/Makefile
2021-10-07 15:02 ` [PATCHSET liburing 0/4] Add no libc support for x86-64 arch Ammar Faizi
` (2 preceding siblings ...)
2021-10-07 15:02 ` [PATCH liburing 3/4] Add no libc build support Ammar Faizi
@ 2021-10-07 15:02 ` Ammar Faizi
3 siblings, 0 replies; 26+ messages in thread
From: Ammar Faizi @ 2021-10-07 15:02 UTC (permalink / raw)
To: Jens Axboe, Pavel Begunkov, io-uring Mailing List
Cc: Bedirhan KURT, Louvian Lyndal, Ammar Faizi
Conditonal variable to enable nolibc build.
Link: https://github.com/axboe/liburing/issues/443
Signed-off-by: Ammar Faizi <[email protected]>
---
configure | 7 +++++++
src/Makefile | 13 ++++++++++++-
2 files changed, 19 insertions(+), 1 deletion(-)
diff --git a/configure b/configure
index 92f51bd..6bdcead 100755
--- a/configure
+++ b/configure
@@ -358,6 +358,13 @@ print_config "has_memfd_create" "$has_memfd_create"
#############################################################################
+if test "$LIBURING_NOLIBC" = "y" -o "$LIBURING_NOLIBC" = "yes" -o "$LIBURING_NOLIBC" = "1"; then
+ output_sym "LIBURING_NOLIBC"
+ LIBURING_NOLIBC="yes"
+else
+ LIBURING_NOLIBC="no"
+fi
+print_config "LIBURING_NOLIBC" "$LIBURING_NOLIBC"
if test "$__kernel_rwf_t" = "yes"; then
output_sym "CONFIG_HAVE_KERNEL_RWF_T"
diff --git a/src/Makefile b/src/Makefile
index 5e46a9d..bc42675 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -32,11 +32,22 @@ endif
all: $(all_targets)
-liburing_srcs := setup.c queue.c syscall.c register.c
+liburing_srcs := setup.c queue.c register.c
+
+ifeq ($(LIBURING_NOLIBC),y)
+ liburing_srcs += nolibc.c
+ override CFLAGS += -nostdlib -nolibc -nodefaultlibs -ffreestanding -fno-stack-protector -fpic
+ override CPPFLAGS += -nostdlib -nolibc -nodefaultlibs -ffreestanding -fno-stack-protector -fpic
+ override LINK_FLAGS += -nostdlib -nolibc -nodefaultlibs -fpic
+else
+ liburing_srcs += syscall.c
+endif
liburing_objs := $(patsubst %.c,%.ol,$(liburing_srcs))
liburing_sobjs := $(patsubst %.c,%.os,$(liburing_srcs))
+$(liburing_srcs): syscall.h lib.h
+
$(liburing_objs) $(liburing_sobjs): include/liburing/io_uring.h
%.os: %.c
--
2.30.2
^ permalink raw reply related [flat|nested] 26+ messages in thread