| #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 | |
| /* | |
| * Remove the address tag from a virtual address, if present. | |
| */ | |
| .macro clear_address_tag, dst, addr | |
| tst \addr, #(1 << 55) | |
| bic \dst, \addr, #(0xff << 56) | |
| csel \dst, \dst, \addr, eq | |
| .endm | |
| #endif |