diff options
| author | Joey Gouly <joey.gouly@arm.com> | 2024-08-22 16:11:01 +0100 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2024-09-04 12:54:04 +0100 |
| commit | 7f955be9f887d3ce77afb61ea74d907f06fe6f1e (patch) | |
| tree | 64ed14dae6ec546dc08e80191e9dbce9bb736c47 /arch/arm64/include/asm/pgtable.h | |
| parent | fc2d9cd33040630f9d6ff819f1f326d51b354429 (diff) | |
arm64: implement PKEYS support
Implement the PKEYS interface, using the Permission Overlay Extension.
Signed-off-by: Joey Gouly <joey.gouly@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20240822151113.1479789-19-joey.gouly@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'arch/arm64/include/asm/pgtable.h')
| -rw-r--r-- | arch/arm64/include/asm/pgtable.h | 22 |
1 files changed, 21 insertions, 1 deletions
diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index 61a674942a6b..96c2b0b07c4c 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -34,6 +34,7 @@ #include <asm/cmpxchg.h> #include <asm/fixmap.h> +#include <asm/por.h> #include <linux/mmdebug.h> #include <linux/mm_types.h> #include <linux/sched.h> @@ -149,6 +150,24 @@ static inline pteval_t __phys_to_pte_val(phys_addr_t phys) #define pte_accessible(mm, pte) \ (mm_tlb_flush_pending(mm) ? pte_present(pte) : pte_valid(pte)) +static inline bool por_el0_allows_pkey(u8 pkey, bool write, bool execute) +{ + u64 por; + + if (!system_supports_poe()) + return true; + + por = read_sysreg_s(SYS_POR_EL0); + + if (write) + return por_elx_allows_write(por, pkey); + + if (execute) + return por_elx_allows_exec(por, pkey); + + return por_elx_allows_read(por, pkey); +} + /* * p??_access_permitted() is true for valid user mappings (PTE_USER * bit set, subject to the write permission check). For execute-only @@ -159,7 +178,8 @@ static inline pteval_t __phys_to_pte_val(phys_addr_t phys) #define pte_access_permitted_no_overlay(pte, write) \ (((pte_val(pte) & (PTE_VALID | PTE_USER)) == (PTE_VALID | PTE_USER)) && (!(write) || pte_write(pte))) #define pte_access_permitted(pte, write) \ - pte_access_permitted_no_overlay(pte, write) + (pte_access_permitted_no_overlay(pte, write) && \ + por_el0_allows_pkey(FIELD_GET(PTE_PO_IDX_MASK, pte_val(pte)), write, false)) #define pmd_access_permitted(pmd, write) \ (pte_access_permitted(pmd_pte(pmd), (write))) #define pud_access_permitted(pud, write) \ |