[4/5] arm: Add the clone3 wrapper

Message ID 20230203171237.1220878-5-adhemerval.zanella@linaro.org
State Superseded
Headers
Series Add clone3 support for multiple architectures |

Checks

Context Check Description
dj/TryBot-apply_patch success Patch applied to master at the time it was sent

Commit Message

Adhemerval Zanella Netto Feb. 3, 2023, 5:12 p.m. UTC
  It follows the internal signature:

  extern int clone3 (struct clone_args *__cl_args, size_t __size,
		    int (*__func) (void *__arg), void *__arg);

Checked on arm-linux-gnueabihf.
---
 sysdeps/unix/sysv/linux/arm/clone3.S | 80 ++++++++++++++++++++++++++++
 sysdeps/unix/sysv/linux/arm/sysdep.h |  1 +
 2 files changed, 81 insertions(+)
 create mode 100644 sysdeps/unix/sysv/linux/arm/clone3.S
  

Comments

Adhemerval Zanella Netto May 25, 2023, 5:36 p.m. UTC | #1
Ping.

On 03/02/23 14:12, Adhemerval Zanella wrote:
> It follows the internal signature:
> 
>   extern int clone3 (struct clone_args *__cl_args, size_t __size,
> 		    int (*__func) (void *__arg), void *__arg);
> 
> Checked on arm-linux-gnueabihf.
> ---
>  sysdeps/unix/sysv/linux/arm/clone3.S | 80 ++++++++++++++++++++++++++++
>  sysdeps/unix/sysv/linux/arm/sysdep.h |  1 +
>  2 files changed, 81 insertions(+)
>  create mode 100644 sysdeps/unix/sysv/linux/arm/clone3.S
> 
> diff --git a/sysdeps/unix/sysv/linux/arm/clone3.S b/sysdeps/unix/sysv/linux/arm/clone3.S
> new file mode 100644
> index 0000000000..f236d18390
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/arm/clone3.S
> @@ -0,0 +1,80 @@
> +/* The clone3 syscall wrapper.  Linux/arm version.
> +   Copyright (C) 2023 Free Software Foundation, Inc.
> +
> +   This file is part of the GNU C Library.
> +
> +   The GNU C Library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 of the License, or (at your option) any later version.
> +
> +   The GNU C Library is distributed in the hope that it will be useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with the GNU C Library; if not, see
> +   <https://www.gnu.org/licenses/>.  */
> +
> +#include <sysdep.h>
> +#define _ERRNO_H	1
> +#include <bits/errno.h>
> +
> +/* The userland implementation is:
> +   int clone3 (struct clone_args *cl_args, size_t size,
> +               int (*func)(void *arg), void *arg);
> +
> +   the kernel entry is:
> +   int clone3 (struct clone_args *cl_args, size_t size);
> +
> +   The parameters are passed in registers from userland:
> +   r0: cl_args
> +   r1: size
> +   r2: func
> +   r3: arg  */
> +
> +        .text
> +ENTRY(__clone3)
> +	/* Sanity check args.  */
> +	cmp	r0, #0
> +	ite	ne
> +	cmpne	r1, #0
> +	moveq	r0, #-EINVAL
> +	beq	PLTJMP(syscall_error)
> +
> +	/* Do the syscall, the kernel expects:
> +	   r7: system call number:
> +	   r0: cl_args
> +	   r1: size  */
> +	push    { r7 }
> +	cfi_adjust_cfa_offset (4)
> +	cfi_rel_offset (r7, 0)
> +	ldr     r7, =SYS_ify(clone3)
> +	swi	0x0
> +	cfi_endproc
> +
> +	cmp	r0, #0
> +	beq	1f
> +	pop     {r7}
> +	blt	PLTJMP(C_SYMBOL_NAME(__syscall_error))
> +	RETINSTR(, lr)
> +
> +	cfi_startproc
> +PSEUDO_END (__clone3)
> +
> +1:
> +	.fnstart
> +	.cantunwind
> +	mov	r0, r3
> +	mov	ip, r2
> +	BLX (ip)
> +
> +	/* And we are done, passing the return value through r0.  */
> +	ldr	r7, =SYS_ify(exit)
> +	swi	0x0
> +
> +	.fnend
> +
> +libc_hidden_def (__clone3)
> +weak_alias (__clone3, clone3)
> diff --git a/sysdeps/unix/sysv/linux/arm/sysdep.h b/sysdeps/unix/sysv/linux/arm/sysdep.h
> index 2f321881c8..57fc5f16bd 100644
> --- a/sysdeps/unix/sysv/linux/arm/sysdep.h
> +++ b/sysdeps/unix/sysv/linux/arm/sysdep.h
> @@ -362,6 +362,7 @@ __local_syscall_error:						\
>  #define HAVE_CLOCK_GETTIME_VSYSCALL	"__vdso_clock_gettime"
>  #define HAVE_CLOCK_GETTIME64_VSYSCALL	"__vdso_clock_gettime64"
>  #define HAVE_GETTIMEOFDAY_VSYSCALL	"__vdso_gettimeofday"
> +#define HAVE_CLONE3_WRAPPER		1
>  
>  #define LOAD_ARGS_0()
>  #define ASM_ARGS_0
  

Patch

diff --git a/sysdeps/unix/sysv/linux/arm/clone3.S b/sysdeps/unix/sysv/linux/arm/clone3.S
new file mode 100644
index 0000000000..f236d18390
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/arm/clone3.S
@@ -0,0 +1,80 @@ 
+/* The clone3 syscall wrapper.  Linux/arm version.
+   Copyright (C) 2023 Free Software Foundation, Inc.
+
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <sysdep.h>
+#define _ERRNO_H	1
+#include <bits/errno.h>
+
+/* The userland implementation is:
+   int clone3 (struct clone_args *cl_args, size_t size,
+               int (*func)(void *arg), void *arg);
+
+   the kernel entry is:
+   int clone3 (struct clone_args *cl_args, size_t size);
+
+   The parameters are passed in registers from userland:
+   r0: cl_args
+   r1: size
+   r2: func
+   r3: arg  */
+
+        .text
+ENTRY(__clone3)
+	/* Sanity check args.  */
+	cmp	r0, #0
+	ite	ne
+	cmpne	r1, #0
+	moveq	r0, #-EINVAL
+	beq	PLTJMP(syscall_error)
+
+	/* Do the syscall, the kernel expects:
+	   r7: system call number:
+	   r0: cl_args
+	   r1: size  */
+	push    { r7 }
+	cfi_adjust_cfa_offset (4)
+	cfi_rel_offset (r7, 0)
+	ldr     r7, =SYS_ify(clone3)
+	swi	0x0
+	cfi_endproc
+
+	cmp	r0, #0
+	beq	1f
+	pop     {r7}
+	blt	PLTJMP(C_SYMBOL_NAME(__syscall_error))
+	RETINSTR(, lr)
+
+	cfi_startproc
+PSEUDO_END (__clone3)
+
+1:
+	.fnstart
+	.cantunwind
+	mov	r0, r3
+	mov	ip, r2
+	BLX (ip)
+
+	/* And we are done, passing the return value through r0.  */
+	ldr	r7, =SYS_ify(exit)
+	swi	0x0
+
+	.fnend
+
+libc_hidden_def (__clone3)
+weak_alias (__clone3, clone3)
diff --git a/sysdeps/unix/sysv/linux/arm/sysdep.h b/sysdeps/unix/sysv/linux/arm/sysdep.h
index 2f321881c8..57fc5f16bd 100644
--- a/sysdeps/unix/sysv/linux/arm/sysdep.h
+++ b/sysdeps/unix/sysv/linux/arm/sysdep.h
@@ -362,6 +362,7 @@  __local_syscall_error:						\
 #define HAVE_CLOCK_GETTIME_VSYSCALL	"__vdso_clock_gettime"
 #define HAVE_CLOCK_GETTIME64_VSYSCALL	"__vdso_clock_gettime64"
 #define HAVE_GETTIMEOFDAY_VSYSCALL	"__vdso_gettimeofday"
+#define HAVE_CLONE3_WRAPPER		1
 
 #define LOAD_ARGS_0()
 #define ASM_ARGS_0