1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef __ASM_MMAN_H__ 3 #define __ASM_MMAN_H__ 4 5 #include <linux/compiler.h> 6 #include <linux/types.h> 7 #include <uapi/asm/mman.h> 8 9 static inline unsigned long arch_calc_vm_prot_bits(unsigned long prot, 10 unsigned long pkey __always_unused) 11 { 12 unsigned long ret = 0; 13 14 if (system_supports_bti() && (prot & PROT_BTI)) 15 ret |= VM_ARM64_BTI; 16 17 if (system_supports_mte() && (prot & PROT_MTE)) 18 ret |= VM_MTE; 19 20 return ret; 21 } 22 #define arch_calc_vm_prot_bits(prot, pkey) arch_calc_vm_prot_bits(prot, pkey) 23 24 static inline unsigned long arch_calc_vm_flag_bits(unsigned long flags) 25 { 26 /* 27 * Only allow MTE on anonymous mappings as these are guaranteed to be 28 * backed by tags-capable memory. The vm_flags may be overridden by a 29 * filesystem supporting MTE (RAM-based). 30 */ 31 if (system_supports_mte() && (flags & MAP_ANONYMOUS)) 32 return VM_MTE_ALLOWED; 33 34 return 0; 35 } 36 #define arch_calc_vm_flag_bits(flags) arch_calc_vm_flag_bits(flags) 37 38 static inline bool arch_validate_prot(unsigned long prot, 39 unsigned long addr __always_unused) 40 { 41 unsigned long supported = PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM; 42 43 if (system_supports_bti()) 44 supported |= PROT_BTI; 45 46 if (system_supports_mte()) 47 supported |= PROT_MTE; 48 49 return (prot & ~supported) == 0; 50 } 51 #define arch_validate_prot(prot, addr) arch_validate_prot(prot, addr) 52 53 static inline bool arch_validate_flags(unsigned long vm_flags) 54 { 55 if (!system_supports_mte()) 56 return true; 57 58 /* only allow VM_MTE if VM_MTE_ALLOWED has been set previously */ 59 return !(vm_flags & VM_MTE) || (vm_flags & VM_MTE_ALLOWED); 60 } 61 #define arch_validate_flags(vm_flags) arch_validate_flags(vm_flags) 62 63 #endif /* ! __ASM_MMAN_H__ */ 64