166d37570SDave Hansen #ifndef _ASM_X86_PKEYS_H 266d37570SDave Hansen #define _ASM_X86_PKEYS_H 366d37570SDave Hansen 4e8c24d3aSDave Hansen #define arch_max_pkey() (boot_cpu_has(X86_FEATURE_OSPKE) ? 16 : 1) 566d37570SDave Hansen 684594296SDave Hansen extern int arch_set_user_pkey_access(struct task_struct *tsk, int pkey, 784594296SDave Hansen unsigned long init_val); 884594296SDave Hansen 962b5f7d0SDave Hansen /* 1062b5f7d0SDave Hansen * Try to dedicate one of the protection keys to be used as an 1162b5f7d0SDave Hansen * execute-only protection key. 1262b5f7d0SDave Hansen */ 1362b5f7d0SDave Hansen extern int __execute_only_pkey(struct mm_struct *mm); 1462b5f7d0SDave Hansen static inline int execute_only_pkey(struct mm_struct *mm) 1562b5f7d0SDave Hansen { 1662b5f7d0SDave Hansen if (!boot_cpu_has(X86_FEATURE_OSPKE)) 1762b5f7d0SDave Hansen return 0; 1862b5f7d0SDave Hansen 1962b5f7d0SDave Hansen return __execute_only_pkey(mm); 2062b5f7d0SDave Hansen } 2162b5f7d0SDave Hansen 2262b5f7d0SDave Hansen extern int __arch_override_mprotect_pkey(struct vm_area_struct *vma, 2362b5f7d0SDave Hansen int prot, int pkey); 2462b5f7d0SDave Hansen static inline int arch_override_mprotect_pkey(struct vm_area_struct *vma, 2562b5f7d0SDave Hansen int prot, int pkey) 2662b5f7d0SDave Hansen { 2762b5f7d0SDave Hansen if (!boot_cpu_has(X86_FEATURE_OSPKE)) 2862b5f7d0SDave Hansen return 0; 2962b5f7d0SDave Hansen 3062b5f7d0SDave Hansen return __arch_override_mprotect_pkey(vma, prot, pkey); 3162b5f7d0SDave Hansen } 3262b5f7d0SDave Hansen 337d06d9c9SDave Hansen extern int __arch_set_user_pkey_access(struct task_struct *tsk, int pkey, 347d06d9c9SDave Hansen unsigned long init_val); 357d06d9c9SDave Hansen 36a8502b67SDave Hansen #define ARCH_VM_PKEY_FLAGS (VM_PKEY_BIT0 | VM_PKEY_BIT1 | VM_PKEY_BIT2 | VM_PKEY_BIT3) 37a8502b67SDave Hansen 38e8c24d3aSDave Hansen #define mm_pkey_allocation_map(mm) (mm->context.pkey_allocation_map) 39e8c24d3aSDave Hansen #define mm_set_pkey_allocated(mm, pkey) do { \ 40e8c24d3aSDave Hansen mm_pkey_allocation_map(mm) |= (1U << pkey); \ 41e8c24d3aSDave Hansen } while (0) 42e8c24d3aSDave Hansen #define mm_set_pkey_free(mm, pkey) do { \ 43e8c24d3aSDave Hansen mm_pkey_allocation_map(mm) &= ~(1U << pkey); \ 44e8c24d3aSDave Hansen } while (0) 45e8c24d3aSDave Hansen 46e8c24d3aSDave Hansen static inline 47e8c24d3aSDave Hansen bool mm_pkey_is_allocated(struct mm_struct *mm, int pkey) 48e8c24d3aSDave Hansen { 49e8c24d3aSDave Hansen return mm_pkey_allocation_map(mm) & (1U << pkey); 50e8c24d3aSDave Hansen } 51e8c24d3aSDave Hansen 52e8c24d3aSDave Hansen /* 53e8c24d3aSDave Hansen * Returns a positive, 4-bit key on success, or -1 on failure. 54e8c24d3aSDave Hansen */ 55e8c24d3aSDave Hansen static inline 56e8c24d3aSDave Hansen int mm_pkey_alloc(struct mm_struct *mm) 57e8c24d3aSDave Hansen { 58e8c24d3aSDave Hansen /* 59e8c24d3aSDave Hansen * Note: this is the one and only place we make sure 60e8c24d3aSDave Hansen * that the pkey is valid as far as the hardware is 61e8c24d3aSDave Hansen * concerned. The rest of the kernel trusts that 62e8c24d3aSDave Hansen * only good, valid pkeys come out of here. 63e8c24d3aSDave Hansen */ 64e8c24d3aSDave Hansen u16 all_pkeys_mask = ((1U << arch_max_pkey()) - 1); 65e8c24d3aSDave Hansen int ret; 66e8c24d3aSDave Hansen 67e8c24d3aSDave Hansen /* 68e8c24d3aSDave Hansen * Are we out of pkeys? We must handle this specially 69e8c24d3aSDave Hansen * because ffz() behavior is undefined if there are no 70e8c24d3aSDave Hansen * zeros. 71e8c24d3aSDave Hansen */ 72e8c24d3aSDave Hansen if (mm_pkey_allocation_map(mm) == all_pkeys_mask) 73e8c24d3aSDave Hansen return -1; 74e8c24d3aSDave Hansen 75e8c24d3aSDave Hansen ret = ffz(mm_pkey_allocation_map(mm)); 76e8c24d3aSDave Hansen 77e8c24d3aSDave Hansen mm_set_pkey_allocated(mm, ret); 78e8c24d3aSDave Hansen 79e8c24d3aSDave Hansen return ret; 80e8c24d3aSDave Hansen } 81e8c24d3aSDave Hansen 82e8c24d3aSDave Hansen static inline 83e8c24d3aSDave Hansen int mm_pkey_free(struct mm_struct *mm, int pkey) 84e8c24d3aSDave Hansen { 85e8c24d3aSDave Hansen /* 86e8c24d3aSDave Hansen * pkey 0 is special, always allocated and can never 87e8c24d3aSDave Hansen * be freed. 88e8c24d3aSDave Hansen */ 89e8c24d3aSDave Hansen if (!pkey) 90e8c24d3aSDave Hansen return -EINVAL; 91e8c24d3aSDave Hansen if (!mm_pkey_is_allocated(mm, pkey)) 92e8c24d3aSDave Hansen return -EINVAL; 93e8c24d3aSDave Hansen 94e8c24d3aSDave Hansen mm_set_pkey_free(mm, pkey); 95e8c24d3aSDave Hansen 96e8c24d3aSDave Hansen return 0; 97e8c24d3aSDave Hansen } 98e8c24d3aSDave Hansen 99e8c24d3aSDave Hansen extern int arch_set_user_pkey_access(struct task_struct *tsk, int pkey, 100e8c24d3aSDave Hansen unsigned long init_val); 101e8c24d3aSDave Hansen extern int __arch_set_user_pkey_access(struct task_struct *tsk, int pkey, 102e8c24d3aSDave Hansen unsigned long init_val); 103acd547b2SDave Hansen extern void copy_init_pkru_to_fpregs(void); 104e8c24d3aSDave Hansen 10566d37570SDave Hansen #endif /*_ASM_X86_PKEYS_H */ 106