| Al Viro | b4b8664 | 2016-12-26 04:10:19 -0500 | [diff] [blame] | 1 | #ifndef __ASM_ASM_UACCESS_H |
| 2 | #define __ASM_ASM_UACCESS_H |
| 3 | |
| 4 | #include <asm/alternative.h> |
| 5 | #include <asm/kernel-pgtable.h> |
| 6 | #include <asm/sysreg.h> |
| 7 | #include <asm/assembler.h> |
| 8 | |
| 9 | /* |
| 10 | * User access enabling/disabling macros. |
| 11 | */ |
| 12 | #ifdef CONFIG_ARM64_SW_TTBR0_PAN |
| 13 | .macro __uaccess_ttbr0_disable, tmp1 |
| 14 | mrs \tmp1, ttbr1_el1 // swapper_pg_dir |
| 15 | add \tmp1, \tmp1, #SWAPPER_DIR_SIZE // reserved_ttbr0 at the end of swapper_pg_dir |
| 16 | msr ttbr0_el1, \tmp1 // set reserved TTBR0_EL1 |
| 17 | isb |
| 18 | .endm |
| 19 | |
| 20 | .macro __uaccess_ttbr0_enable, tmp1 |
| 21 | get_thread_info \tmp1 |
| 22 | ldr \tmp1, [\tmp1, #TSK_TI_TTBR0] // load saved TTBR0_EL1 |
| 23 | msr ttbr0_el1, \tmp1 // set the non-PAN TTBR0_EL1 |
| 24 | isb |
| 25 | .endm |
| 26 | |
| 27 | .macro uaccess_ttbr0_disable, tmp1 |
| 28 | alternative_if_not ARM64_HAS_PAN |
| 29 | __uaccess_ttbr0_disable \tmp1 |
| 30 | alternative_else_nop_endif |
| 31 | .endm |
| 32 | |
| 33 | .macro uaccess_ttbr0_enable, tmp1, tmp2 |
| 34 | alternative_if_not ARM64_HAS_PAN |
| 35 | save_and_disable_irq \tmp2 // avoid preemption |
| 36 | __uaccess_ttbr0_enable \tmp1 |
| 37 | restore_irq \tmp2 |
| 38 | alternative_else_nop_endif |
| 39 | .endm |
| 40 | #else |
| 41 | .macro uaccess_ttbr0_disable, tmp1 |
| 42 | .endm |
| 43 | |
| 44 | .macro uaccess_ttbr0_enable, tmp1, tmp2 |
| 45 | .endm |
| 46 | #endif |
| 47 | |
| 48 | /* |
| 49 | * These macros are no-ops when UAO is present. |
| 50 | */ |
| 51 | .macro uaccess_disable_not_uao, tmp1 |
| 52 | uaccess_ttbr0_disable \tmp1 |
| 53 | alternative_if ARM64_ALT_PAN_NOT_UAO |
| 54 | SET_PSTATE_PAN(1) |
| 55 | alternative_else_nop_endif |
| 56 | .endm |
| 57 | |
| 58 | .macro uaccess_enable_not_uao, tmp1, tmp2 |
| 59 | uaccess_ttbr0_enable \tmp1, \tmp2 |
| 60 | alternative_if ARM64_ALT_PAN_NOT_UAO |
| 61 | SET_PSTATE_PAN(0) |
| 62 | alternative_else_nop_endif |
| 63 | .endm |
| 64 | |
| Kristina Martsenko | 276e932 | 2017-05-03 16:37:47 +0100 | [diff] [blame] | 65 | /* |
| 66 | * Remove the address tag from a virtual address, if present. |
| 67 | */ |
| 68 | .macro clear_address_tag, dst, addr |
| 69 | tst \addr, #(1 << 55) |
| 70 | bic \dst, \addr, #(0xff << 56) |
| 71 | csel \dst, \dst, \addr, eq |
| 72 | .endm |
| 73 | |
| Al Viro | b4b8664 | 2016-12-26 04:10:19 -0500 | [diff] [blame] | 74 | #endif |