diff options
Diffstat (limited to 'arch/arm64/include/asm')
| -rw-r--r-- | arch/arm64/include/asm/asm-uaccess.h | 65 | ||||
| -rw-r--r-- | arch/arm64/include/asm/current.h | 10 | ||||
| -rw-r--r-- | arch/arm64/include/asm/uaccess.h | 64 |
3 files changed, 74 insertions, 65 deletions
diff --git a/arch/arm64/include/asm/asm-uaccess.h b/arch/arm64/include/asm/asm-uaccess.h new file mode 100644 index 0000000..df411f3 --- /dev/null +++ b/arch/arm64/include/asm/asm-uaccess.h @@ -0,0 +1,65 @@ +#ifndef __ASM_ASM_UACCESS_H +#define __ASM_ASM_UACCESS_H + +#include <asm/alternative.h> +#include <asm/kernel-pgtable.h> +#include <asm/sysreg.h> +#include <asm/assembler.h> + +/* + * User access enabling/disabling macros. + */ +#ifdef CONFIG_ARM64_SW_TTBR0_PAN + .macro __uaccess_ttbr0_disable, tmp1 + mrs \tmp1, ttbr1_el1 // swapper_pg_dir + add \tmp1, \tmp1, #SWAPPER_DIR_SIZE // reserved_ttbr0 at the end of swapper_pg_dir + msr ttbr0_el1, \tmp1 // set reserved TTBR0_EL1 + isb + .endm + + .macro __uaccess_ttbr0_enable, tmp1 + get_thread_info \tmp1 + ldr \tmp1, [\tmp1, #TSK_TI_TTBR0] // load saved TTBR0_EL1 + msr ttbr0_el1, \tmp1 // set the non-PAN TTBR0_EL1 + isb + .endm + + .macro uaccess_ttbr0_disable, tmp1 +alternative_if_not ARM64_HAS_PAN + __uaccess_ttbr0_disable \tmp1 +alternative_else_nop_endif + .endm + + .macro uaccess_ttbr0_enable, tmp1, tmp2 +alternative_if_not ARM64_HAS_PAN + save_and_disable_irq \tmp2 // avoid preemption + __uaccess_ttbr0_enable \tmp1 + restore_irq \tmp2 +alternative_else_nop_endif + .endm +#else + .macro uaccess_ttbr0_disable, tmp1 + .endm + + .macro uaccess_ttbr0_enable, tmp1, tmp2 + .endm +#endif + +/* + * These macros are no-ops when UAO is present. + */ + .macro uaccess_disable_not_uao, tmp1 + uaccess_ttbr0_disable \tmp1 +alternative_if ARM64_ALT_PAN_NOT_UAO + SET_PSTATE_PAN(1) +alternative_else_nop_endif + .endm + + .macro uaccess_enable_not_uao, tmp1, tmp2 + uaccess_ttbr0_enable \tmp1, \tmp2 +alternative_if ARM64_ALT_PAN_NOT_UAO + SET_PSTATE_PAN(0) +alternative_else_nop_endif + .endm + +#endif diff --git a/arch/arm64/include/asm/current.h b/arch/arm64/include/asm/current.h index f2bcbe2..86c4041 100644 --- a/arch/arm64/include/asm/current.h +++ b/arch/arm64/include/asm/current.h @@ -9,9 +9,17 @@ struct task_struct; +/* + * We don't use read_sysreg() as we want the compiler to cache the value where + * possible. + */ static __always_inline struct task_struct *get_current(void) { - return (struct task_struct *)read_sysreg(sp_el0); + unsigned long sp_el0; + + asm ("mrs %0, sp_el0" : "=r" (sp_el0)); + + return (struct task_struct *)sp_el0; } #define current get_current() diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h index d26750c..46da3ea 100644 --- a/arch/arm64/include/asm/uaccess.h +++ b/arch/arm64/include/asm/uaccess.h @@ -22,8 +22,6 @@ #include <asm/kernel-pgtable.h> #include <asm/sysreg.h> -#ifndef __ASSEMBLY__ - /* * User space memory access functions */ @@ -424,66 +422,4 @@ extern long strncpy_from_user(char *dest, const char __user *src, long count); extern __must_check long strlen_user(const char __user *str); extern __must_check long strnlen_user(const char __user *str, long n); -#else /* __ASSEMBLY__ */ - -#include <asm/assembler.h> - -/* - * User access enabling/disabling macros. - */ -#ifdef CONFIG_ARM64_SW_TTBR0_PAN - .macro __uaccess_ttbr0_disable, tmp1 - mrs \tmp1, ttbr1_el1 // swapper_pg_dir - add \tmp1, \tmp1, #SWAPPER_DIR_SIZE // reserved_ttbr0 at the end of swapper_pg_dir - msr ttbr0_el1, \tmp1 // set reserved TTBR0_EL1 - isb - .endm - - .macro __uaccess_ttbr0_enable, tmp1 - get_thread_info \tmp1 - ldr \tmp1, [\tmp1, #TSK_TI_TTBR0] // load saved TTBR0_EL1 - msr ttbr0_el1, \tmp1 // set the non-PAN TTBR0_EL1 - isb - .endm - - .macro uaccess_ttbr0_disable, tmp1 -alternative_if_not ARM64_HAS_PAN - __uaccess_ttbr0_disable \tmp1 -alternative_else_nop_endif - .endm - - .macro uaccess_ttbr0_enable, tmp1, tmp2 -alternative_if_not ARM64_HAS_PAN - save_and_disable_irq \tmp2 // avoid preemption - __uaccess_ttbr0_enable \tmp1 - restore_irq \tmp2 -alternative_else_nop_endif - .endm -#else - .macro uaccess_ttbr0_disable, tmp1 - .endm - - .macro uaccess_ttbr0_enable, tmp1, tmp2 - .endm -#endif - -/* - * These macros are no-ops when UAO is present. - */ - .macro uaccess_disable_not_uao, tmp1 - uaccess_ttbr0_disable \tmp1 -alternative_if ARM64_ALT_PAN_NOT_UAO - SET_PSTATE_PAN(1) -alternative_else_nop_endif - .endm - - .macro uaccess_enable_not_uao, tmp1, tmp2 - uaccess_ttbr0_enable \tmp1, \tmp2 -alternative_if ARM64_ALT_PAN_NOT_UAO - SET_PSTATE_PAN(0) -alternative_else_nop_endif - .endm - -#endif /* __ASSEMBLY__ */ - #endif /* __ASM_UACCESS_H */ |
