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| author | Nicolas Pitre <nicolas.pitre@linaro.org> | 2017-07-28 21:35:35 +0200 |
|---|---|---|
| committer | Nicolas Pitre <nicolas.pitre@linaro.org> | 2017-09-11 01:31:46 +0200 |
| commit | 8fcd6c45f5a65621ec809b7866a3623e9a01d4ed (patch) | |
| tree | 2e6eea80b386c293d20e5bb813b8b70bff78baf1 | |
| parent | Linux 4.13 (diff) | |
| download | linux-8fcd6c45f5a65621ec809b7866a3623e9a01d4ed.tar.xz linux-8fcd6c45f5a65621ec809b7866a3623e9a01d4ed.zip | |
ARM: implement get_tls syscall
When there is no dedicated register to hold the tp value and no MMU
to provide a fixed address kuser helper entry point, all that is
left as fallback is a syscall.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Mickael GUENE <mickael.guene@st.com>
Tested-by: Vincent Abriou <vincent.abriou@st.com>
Tested-by: Andras Szemzo <szemzo.andras@gmail.com>
| -rw-r--r-- | arch/arm/include/uapi/asm/unistd.h | 1 | ||||
| -rw-r--r-- | arch/arm/kernel/traps.c | 3 |
2 files changed, 4 insertions, 0 deletions
diff --git a/arch/arm/include/uapi/asm/unistd.h b/arch/arm/include/uapi/asm/unistd.h index 28bd456494a3..575b25fc29c6 100644 --- a/arch/arm/include/uapi/asm/unistd.h +++ b/arch/arm/include/uapi/asm/unistd.h @@ -35,5 +35,6 @@ #define __ARM_NR_usr26 (__ARM_NR_BASE+3) #define __ARM_NR_usr32 (__ARM_NR_BASE+4) #define __ARM_NR_set_tls (__ARM_NR_BASE+5) +#define __ARM_NR_get_tls (__ARM_NR_BASE+6) #endif /* _UAPI__ASM_ARM_UNISTD_H */ diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c index 948c648fea00..43c0560f7b2d 100644 --- a/arch/arm/kernel/traps.c +++ b/arch/arm/kernel/traps.c @@ -647,6 +647,9 @@ asmlinkage int arm_syscall(int no, struct pt_regs *regs) set_tls(regs->ARM_r0); return 0; + case NR(get_tls): + return current_thread_info()->tp_value[0]; + default: /* Calls 9f00xx..9f07ff are defined to return -ENOSYS if not implemented, rather than raising SIGILL. This |