diff --git a/arch/arm64/include/asm/pgtable-hwdef.h b/arch/arm64/include/asm/pgtable-hwdef.h index f658aafc47dfa..e4944d517c999 100644 --- a/arch/arm64/include/asm/pgtable-hwdef.h +++ b/arch/arm64/include/asm/pgtable-hwdef.h @@ -170,6 +170,14 @@ #define PTE_ATTRINDX(t) (_AT(pteval_t, (t)) << 2) #define PTE_ATTRINDX_MASK (_AT(pteval_t, 7) << 2) +/* + * PIIndex[3:0] encoding (Permission Indirection Extension) + */ +#define PTE_PI_IDX_0 6 /* AP[1], USER */ +#define PTE_PI_IDX_1 51 /* DBM */ +#define PTE_PI_IDX_2 53 /* PXN */ +#define PTE_PI_IDX_3 54 /* UXN */ + /* * Memory Attribute override for Stage-2 (MemAttr[3:0]) */ diff --git a/arch/arm64/include/asm/pgtable-prot.h b/arch/arm64/include/asm/pgtable-prot.h index a45af0a22b256..eed814b00a389 100644 --- a/arch/arm64/include/asm/pgtable-prot.h +++ b/arch/arm64/include/asm/pgtable-prot.h @@ -107,4 +107,54 @@ extern bool arm64_use_ng_mappings; #endif /* __ASSEMBLY__ */ +#define pte_pi_index(pte) ( \ + ((pte & BIT(PTE_PI_IDX_3)) >> (PTE_PI_IDX_3 - 3)) | \ + ((pte & BIT(PTE_PI_IDX_2)) >> (PTE_PI_IDX_2 - 2)) | \ + ((pte & BIT(PTE_PI_IDX_1)) >> (PTE_PI_IDX_1 - 1)) | \ + ((pte & BIT(PTE_PI_IDX_0)) >> (PTE_PI_IDX_0 - 0))) + +/* + * Page types used via Permission Indirection Extension (PIE). PIE uses + * the USER, DBM, PXN and UXN bits to to generate an index which is used + * to look up the actual permission in PIR_ELx and PIRE0_EL1. We define + * combinations we use on non-PIE systems with the same encoding, for + * convenience these are listed here as comments as are the unallocated + * encodings. + */ + +/* 0: PAGE_DEFAULT */ +/* 1: PTE_USER */ +/* 2: PTE_WRITE */ +/* 3: PTE_WRITE | PTE_USER */ +/* 4: PAGE_EXECONLY PTE_PXN */ +/* 5: PAGE_READONLY_EXEC PTE_PXN | PTE_USER */ +/* 6: PTE_PXN | PTE_WRITE */ +/* 7: PAGE_SHARED_EXEC PTE_PXN | PTE_WRITE | PTE_USER */ +/* 8: PAGE_KERNEL_ROX PTE_UXN */ +/* 9: PTE_UXN | PTE_USER */ +/* a: PAGE_KERNEL_EXEC PTE_UXN | PTE_WRITE */ +/* b: PTE_UXN | PTE_WRITE | PTE_USER */ +/* c: PAGE_KERNEL_RO PTE_UXN | PTE_PXN */ +/* d: PAGE_READONLY PTE_UXN | PTE_PXN | PTE_USER */ +/* e: PAGE_KERNEL PTE_UXN | PTE_PXN | PTE_WRITE */ +/* f: PAGE_SHARED PTE_UXN | PTE_PXN | PTE_WRITE | PTE_USER */ + +#define PIE_E0 ( \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_EXECONLY), PIE_X_O) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_READONLY_EXEC), PIE_RX) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_SHARED_EXEC), PIE_RWX) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_READONLY), PIE_R) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_SHARED), PIE_RW)) + +#define PIE_E1 ( \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_EXECONLY), PIE_NONE_O) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_READONLY_EXEC), PIE_R) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_SHARED_EXEC), PIE_RW) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_READONLY), PIE_R) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_SHARED), PIE_RW) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_KERNEL_ROX), PIE_RX) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_KERNEL_EXEC), PIE_RWX) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_KERNEL_RO), PIE_R) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_KERNEL), PIE_RW)) + #endif /* __ASM_PGTABLE_PROT_H */