michaelh/zephyr
1
0
Fork 0
Code Releases Activity

aarch64: userspace: Implement syscalls

Browse source 
This patch adds the code managing the syscalls. The privileged stack
is setup before jumping into the real syscall.

Signed-off-by: Carlo Caione <ccaione@baylibre.com>
This commit is contained in:
Carlo Caione 2020-11-26 10:28:07 +01:00 • committed by Anas Nashif
commit dacd176991
8 changed files with 211 additions and 1 deletions
Download patch file Download diff file Expand all files Collapse all files

132
include/arch/arm/aarch64/syscall.h
View file

@ -19,6 +19,7 @@
#define _SVC_CALL_CONTEXT_SWITCH 0
#define _SVC_CALL_IRQ_OFFLOAD 1
#define _SVC_CALL_RUNTIME_EXCEPT 2
#define _SVC_CALL_SYSTEM_CALL 3
#ifdef CONFIG_USERSPACE
#ifndef _ASMLANGUAGE
@ -31,6 +32,137 @@
extern "C" {
#endif
/*
* Syscall invocation macros. arm-specific machine constraints used to ensure
* args land in the proper registers.
*/
static inline uintptr_t arch_syscall_invoke6(uintptr_t arg1, uintptr_t arg2,
uintptr_t arg3, uintptr_t arg4,
uintptr_t arg5, uintptr_t arg6,
uintptr_t call_id)
{
register uint64_t ret __asm__("x0") = arg1;
register uint64_t r1 __asm__("x1") = arg2;
register uint64_t r2 __asm__("x2") = arg3;
register uint64_t r3 __asm__("x3") = arg4;
register uint64_t r4 __asm__("x4") = arg5;
register uint64_t r5 __asm__("x5") = arg6;
register uint64_t r8 __asm__("x8") = call_id;
__asm__ volatile("svc %[svid]\n"
: "=r"(ret)
: [svid] "i" (_SVC_CALL_SYSTEM_CALL),
"r" (ret), "r" (r1), "r" (r2), "r" (r3),
"r" (r4), "r" (r5), "r" (r8)
: "memory");
return ret;
}
static inline uintptr_t arch_syscall_invoke5(uintptr_t arg1, uintptr_t arg2,
uintptr_t arg3, uintptr_t arg4,
uintptr_t arg5,
uintptr_t call_id)
{
register uint64_t ret __asm__("x0") = arg1;
register uint64_t r1 __asm__("x1") = arg2;
register uint64_t r2 __asm__("x2") = arg3;
register uint64_t r3 __asm__("x3") = arg4;
register uint64_t r4 __asm__("x4") = arg5;
register uint64_t r8 __asm__("x8") = call_id;
__asm__ volatile("svc %[svid]\n"
: "=r"(ret)
: [svid] "i" (_SVC_CALL_SYSTEM_CALL),
"r" (ret), "r" (r1), "r" (r2), "r" (r3),
"r" (r4), "r" (r8)
: "memory");
return ret;
}
static inline uintptr_t arch_syscall_invoke4(uintptr_t arg1, uintptr_t arg2,
uintptr_t arg3, uintptr_t arg4,
uintptr_t call_id)
{
register uint64_t ret __asm__("x0") = arg1;
register uint64_t r1 __asm__("x1") = arg2;
register uint64_t r2 __asm__("x2") = arg3;
register uint64_t r3 __asm__("x3") = arg4;
register uint64_t r8 __asm__("x8") = call_id;
__asm__ volatile("svc %[svid]\n"
: "=r"(ret)
: [svid] "i" (_SVC_CALL_SYSTEM_CALL),
"r" (ret), "r" (r1), "r" (r2), "r" (r3),
"r" (r8)
: "memory");
return ret;
}
static inline uintptr_t arch_syscall_invoke3(uintptr_t arg1, uintptr_t arg2,
uintptr_t arg3,
uintptr_t call_id)
{
register uint64_t ret __asm__("x0") = arg1;
register uint64_t r1 __asm__("x1") = arg2;
register uint64_t r2 __asm__("x2") = arg3;
register uint64_t r8 __asm__("x8") = call_id;
__asm__ volatile("svc %[svid]\n"
: "=r"(ret)
: [svid] "i" (_SVC_CALL_SYSTEM_CALL),
"r" (ret), "r" (r1), "r" (r2), "r" (r8)
: "memory");
return ret;
}
static inline uintptr_t arch_syscall_invoke2(uintptr_t arg1, uintptr_t arg2,
uintptr_t call_id)
{
register uint64_t ret __asm__("x0") = arg1;
register uint64_t r1 __asm__("x1") = arg2;
register uint64_t r8 __asm__("x8") = call_id;
__asm__ volatile("svc %[svid]\n"
: "=r"(ret)
: [svid] "i" (_SVC_CALL_SYSTEM_CALL),
"r" (ret), "r" (r1), "r" (r8)
: "memory");
return ret;
}
static inline uintptr_t arch_syscall_invoke1(uintptr_t arg1,
uintptr_t call_id)
{
register uint64_t ret __asm__("x0") = arg1;
register uint64_t r8 __asm__("x8") = call_id;
__asm__ volatile("svc %[svid]\n"
: "=r"(ret)
: [svid] "i" (_SVC_CALL_SYSTEM_CALL),
"r" (ret), "r" (r8)
: "memory");
return ret;
}
static inline uintptr_t arch_syscall_invoke0(uintptr_t call_id)
{
register uint64_t ret __asm__("x0");
register uint64_t r8 __asm__("x8") = call_id;
__asm__ volatile("svc %[svid]\n"
: "=r"(ret)
: [svid] "i" (_SVC_CALL_SYSTEM_CALL),
"r" (ret), "r" (r8)
: "memory");
return ret;
}
static inline bool arch_is_user_context(void)
{
uint64_t tpidrro_el0;

4
include/arch/arm/aarch64/thread.h
View file

@ -40,7 +40,9 @@ struct _callee_saved {
typedef struct _callee_saved _callee_saved_t;
struct _thread_arch {
/* empty */
#ifdef CONFIG_USERSPACE
uint64_t priv_stack_start;
#endif
};
typedef struct _thread_arch _thread_arch_t;