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Diffstat (limited to 'arch/x86/include/asm/pkeys.h')
-rw-r--r--arch/x86/include/asm/pkeys.h73
1 files changed, 72 insertions, 1 deletions
diff --git a/arch/x86/include/asm/pkeys.h b/arch/x86/include/asm/pkeys.h
index 7b84565c916c..34684adb6899 100644
--- a/arch/x86/include/asm/pkeys.h
+++ b/arch/x86/include/asm/pkeys.h
@@ -10,7 +10,6 @@ extern int arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
* Try to dedicate one of the protection keys to be used as an
* execute-only protection key.
*/
-#define PKEY_DEDICATED_EXECUTE_ONLY 15
extern int __execute_only_pkey(struct mm_struct *mm);
static inline int execute_only_pkey(struct mm_struct *mm)
{
@@ -31,4 +30,76 @@ static inline int arch_override_mprotect_pkey(struct vm_area_struct *vma,
return __arch_override_mprotect_pkey(vma, prot, pkey);
}
+extern int __arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
+ unsigned long init_val);
+
+#define ARCH_VM_PKEY_FLAGS (VM_PKEY_BIT0 | VM_PKEY_BIT1 | VM_PKEY_BIT2 | VM_PKEY_BIT3)
+
+#define mm_pkey_allocation_map(mm) (mm->context.pkey_allocation_map)
+#define mm_set_pkey_allocated(mm, pkey) do { \
+ mm_pkey_allocation_map(mm) |= (1U << pkey); \
+} while (0)
+#define mm_set_pkey_free(mm, pkey) do { \
+ mm_pkey_allocation_map(mm) &= ~(1U << pkey); \
+} while (0)
+
+static inline
+bool mm_pkey_is_allocated(struct mm_struct *mm, int pkey)
+{
+ return mm_pkey_allocation_map(mm) & (1U << pkey);
+}
+
+/*
+ * Returns a positive, 4-bit key on success, or -1 on failure.
+ */
+static inline
+int mm_pkey_alloc(struct mm_struct *mm)
+{
+ /*
+ * Note: this is the one and only place we make sure
+ * that the pkey is valid as far as the hardware is
+ * concerned. The rest of the kernel trusts that
+ * only good, valid pkeys come out of here.
+ */
+ u16 all_pkeys_mask = ((1U << arch_max_pkey()) - 1);
+ int ret;
+
+ /*
+ * Are we out of pkeys? We must handle this specially
+ * because ffz() behavior is undefined if there are no
+ * zeros.
+ */
+ if (mm_pkey_allocation_map(mm) == all_pkeys_mask)
+ return -1;
+
+ ret = ffz(mm_pkey_allocation_map(mm));
+
+ mm_set_pkey_allocated(mm, ret);
+
+ return ret;
+}
+
+static inline
+int mm_pkey_free(struct mm_struct *mm, int pkey)
+{
+ /*
+ * pkey 0 is special, always allocated and can never
+ * be freed.
+ */
+ if (!pkey)
+ return -EINVAL;
+ if (!mm_pkey_is_allocated(mm, pkey))
+ return -EINVAL;
+
+ mm_set_pkey_free(mm, pkey);
+
+ return 0;
+}
+
+extern int arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
+ unsigned long init_val);
+extern int __arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
+ unsigned long init_val);
+extern void copy_init_pkru_to_fpregs(void);
+
#endif /*_ASM_X86_PKEYS_H */