ARM: uaccess: integrate uaccess_save and uaccess_restore (8ede890b) · Commits · 戴 / test

arch/arm/include/asm/uaccess-asm.h

+13 −17

Original line number	Diff line number	Diff line
		@@ -67,30 +67,23 @@
		#endif
		.endm

		.macro uaccess_save, tmp
		#ifdef CONFIG_CPU_SW_DOMAIN_PAN
		mrc p15, 0, \tmp, c3, c0, 0
		str \tmp, [sp, #SVC_DACR]
		#endif
		.endm

		.macro uaccess_restore
		#ifdef CONFIG_CPU_SW_DOMAIN_PAN
		ldr r0, [sp, #SVC_DACR]
		mcr p15, 0, r0, c3, c0, 0
		#define DACR(x...) x
		#else
		#define DACR(x...)
		#endif
		.endm

		/*
		* Save the address limit on entry to a privileged exception and
		* if using PAN, save and disable usermode access.
		*/
		.macro uaccess_entry, tsk, tmp0, tmp1, tmp2, disable
		ldr \tmp0, [\tsk, #TI_ADDR_LIMIT]
		mov \tmp1, #TASK_SIZE
		str \tmp1, [\tsk, #TI_ADDR_LIMIT]
		str \tmp0, [sp, #SVC_ADDR_LIMIT]
		uaccess_save \tmp0
		ldr \tmp1, [\tsk, #TI_ADDR_LIMIT]
		mov \tmp2, #TASK_SIZE
		str \tmp2, [\tsk, #TI_ADDR_LIMIT]
		DACR( mrc p15, 0, \tmp0, c3, c0, 0)
		DACR( str \tmp0, [sp, #SVC_DACR])
		str \tmp1, [sp, #SVC_ADDR_LIMIT]
		.if \disable
		uaccess_disable \tmp0
		.endif
		@@ -99,8 +92,11 @@
		/* Restore the user access state previously saved by uaccess_entry */
		.macro uaccess_exit, tsk, tmp0, tmp1
		ldr \tmp1, [sp, #SVC_ADDR_LIMIT]
		uaccess_restore
		DACR( ldr \tmp0, [sp, #SVC_DACR])
		str \tmp1, [\tsk, #TI_ADDR_LIMIT]
		DACR( mcr p15, 0, \tmp0, c3, c0, 0)
		.endm

		#undef DACR

		#endif /* __ASM_UACCESS_ASM_H__ */