Add a pgprot_pbha() helper that modifies a pgprot_t to include a pbha value. The value is checked against those that were listed as only affecting performance.
Signed-off-by: James Morse <[email protected]> --- arch/arm64/include/asm/pgtable-hwdef.h | 1 + arch/arm64/include/asm/pgtable.h | 12 ++++++++++++ arch/arm64/kernel/cpufeature.c | 1 + 3 files changed, 14 insertions(+) diff --git a/arch/arm64/include/asm/pgtable-hwdef.h b/arch/arm64/include/asm/pgtable-hwdef.h index 3d41242c52b0..bef11fb9a255 100644 --- a/arch/arm64/include/asm/pgtable-hwdef.h +++ b/arch/arm64/include/asm/pgtable-hwdef.h @@ -154,6 +154,7 @@ #define PTE_CONT (_AT(pteval_t, 1) << 52) /* Contiguous range */ #define PTE_PXN (_AT(pteval_t, 1) << 53) /* Privileged XN */ #define PTE_UXN (_AT(pteval_t, 1) << 54) /* User XN */ +#define PTE_PBHA_MASK (_AT(pteval_t, 0xf) << 59) /* Page Base Hardware Attributes */ #define PTE_ADDR_LOW (((_AT(pteval_t, 1) << (48 - PAGE_SHIFT)) - 1) << PAGE_SHIFT) #ifdef CONFIG_ARM64_PA_BITS_52 diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index dfa76afa0ccf..3bc242db2c3c 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -518,6 +518,18 @@ static inline pmd_t pmd_mkdevmap(pmd_t pmd) __pgprot_modify(prot, PTE_ATTRINDX_MASK, \ PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN) + +extern unsigned long arm64_pbha_perf_only_values; +static inline unsigned long __pbha_check_perf_only(unsigned long pbha_val) +{ + if (test_bit(pbha_val, &arm64_pbha_perf_only_values)) + return FIELD_PREP(PTE_PBHA_MASK, pbha_val); + return 0; +} + +#define pgprot_pbha(prot, pbha_val) \ + __pgprot_modify(prot, PTE_PBHA_MASK, __pbha_check_perf_only(pbha_val)) + #define __HAVE_PHYS_MEM_ACCESS_PROT struct file; extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 548c6f96a878..88f0f805b938 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -112,6 +112,7 @@ bool arm64_use_ng_mappings = false; EXPORT_SYMBOL(arm64_use_ng_mappings); unsigned long __ro_after_init arm64_pbha_perf_only_values; +EXPORT_SYMBOL(arm64_pbha_perf_only_values); /* * Permit PER_LINUX32 and execve() of 32-bit binaries even if not all CPUs -- 2.30.2 _______________________________________________ kvmarm mailing list [email protected] https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
