1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef __ASM_MMAN_H__ 3 #define __ASM_MMAN_H__ 4 5 #include <uapi/asm/mman.h> 6 7 #ifndef BUILD_VDSO 8 #include <linux/compiler.h> 9 #include <linux/fs.h> 10 #include <linux/shmem_fs.h> 11 #include <linux/types.h> 12 13 static inline unsigned long arch_calc_vm_prot_bits(unsigned long prot, 14 unsigned long pkey) 15 { 16 unsigned long ret = 0; 17 18 if (system_supports_bti() && (prot & PROT_BTI)) 19 ret |= VM_ARM64_BTI; 20 21 if (system_supports_mte() && (prot & PROT_MTE)) 22 ret |= VM_MTE; 23 24 #ifdef CONFIG_ARCH_HAS_PKEYS 25 if (system_supports_poe()) { 26 ret |= pkey & BIT(0) ? VM_PKEY_BIT0 : 0; 27 ret |= pkey & BIT(1) ? VM_PKEY_BIT1 : 0; 28 ret |= pkey & BIT(2) ? VM_PKEY_BIT2 : 0; 29 } 30 #endif 31 32 return ret; 33 } 34 #define arch_calc_vm_prot_bits(prot, pkey) arch_calc_vm_prot_bits(prot, pkey) 35 36 static inline unsigned long arch_calc_vm_flag_bits(struct file *file, 37 unsigned long flags) 38 { 39 /* 40 * Only allow MTE on anonymous mappings as these are guaranteed to be 41 * backed by tags-capable memory. The vm_flags may be overridden by a 42 * filesystem supporting MTE (RAM-based). 43 */ 44 if (system_supports_mte()) { 45 if (flags & (MAP_ANONYMOUS | MAP_HUGETLB)) 46 return VM_MTE_ALLOWED; 47 if (shmem_file(file)) 48 return VM_MTE_ALLOWED; 49 } 50 51 return 0; 52 } 53 #define arch_calc_vm_flag_bits(file, flags) arch_calc_vm_flag_bits(file, flags) 54 55 static inline bool arch_validate_prot(unsigned long prot, 56 unsigned long addr __always_unused) 57 { 58 unsigned long supported = PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM; 59 60 if (system_supports_bti()) 61 supported |= PROT_BTI; 62 63 if (system_supports_mte()) 64 supported |= PROT_MTE; 65 66 return (prot & ~supported) == 0; 67 } 68 #define arch_validate_prot(prot, addr) arch_validate_prot(prot, addr) 69 70 static inline bool arch_validate_flags(unsigned long vm_flags) 71 { 72 if (system_supports_mte()) { 73 /* 74 * only allow VM_MTE if VM_MTE_ALLOWED has been set 75 * previously 76 */ 77 if ((vm_flags & VM_MTE) && !(vm_flags & VM_MTE_ALLOWED)) 78 return false; 79 } 80 81 if (system_supports_gcs() && (vm_flags & VM_SHADOW_STACK)) { 82 /* An executable GCS isn't a good idea. */ 83 if (vm_flags & VM_EXEC) 84 return false; 85 86 /* The memory management core should prevent this */ 87 VM_WARN_ON(vm_flags & VM_SHARED); 88 } 89 90 return true; 91 92 } 93 #define arch_validate_flags(vm_flags) arch_validate_flags(vm_flags) 94 95 #endif /* !BUILD_VDSO */ 96 97 #endif /* ! __ASM_MMAN_H__ */ 98