[RFC PATCH 01/15] x86/pkeys: Create pkeys_internal.h

ira.weiny
2020-07-14T07:04:04Z

From: Ira Weiny <ira.weiny@intel.com>

Protection Keys User (PKU) and Protection Keys Supervisor (PKS) work in
similar fashions.

Share code between them by creating a header with common defines, move
those defines into this header, change their names to reflect the new
use, and include the header where needed.

Signed-off-by: Ira Weiny <ira.weiny@intel.com>
---
arch/x86/include/asm/pgtable.h | 13 ++++++-------
arch/x86/include/asm/pkeys.h | 2 ++
arch/x86/include/asm/pkeys_internal.h | 11 +++++++++++
arch/x86/include/asm/processor.h | 1 +
arch/x86/kernel/fpu/xstate.c | 8 ++++----
arch/x86/mm/pkeys.c | 14 ++++++--------
6 files changed, 30 insertions(+), 19 deletions(-)
create mode 100644 arch/x86/include/asm/pkeys_internal.h

diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index 76aa21e8128d..30e97fc8a683 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -1364,9 +1364,7 @@ static inline pmd_t pmd_swp_clear_uffd_wp(pmd_t pmd)
}
#endif /* CONFIG_HAVE_ARCH_USERFAULTFD_WP */

-#define PKRU_AD_BIT 0x1
-#define PKRU_WD_BIT 0x2
-#define PKRU_BITS_PER_PKEY 2
+#include <asm/pkeys_internal.h>

#ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
extern u32 init_pkru_value;
@@ -1376,18 +1374,19 @@ extern u32 init_pkru_value;

static inline bool __pkru_allows_read(u32 pkru, u16 pkey)
{
- int pkru_pkey_bits = pkey * PKRU_BITS_PER_PKEY;
- return !(pkru & (PKRU_AD_BIT << pkru_pkey_bits));
+ int pkru_pkey_bits = pkey * PKR_BITS_PER_PKEY;
+
+ return !(pkru & (PKR_AD_BIT << pkru_pkey_bits));
}

static inline bool __pkru_allows_write(u32 pkru, u16 pkey)
{
- int pkru_pkey_bits = pkey * PKRU_BITS_PER_PKEY;
+ int pkru_pkey_bits = pkey * PKR_BITS_PER_PKEY;
/*
* Access-disable disables writes too so we need to check
* both bits here.
*/
- return !(pkru & ((PKRU_AD_BIT|PKRU_WD_BIT) << pkru_pkey_bits));
+ return !(pkru & ((PKR_AD_BIT|PKR_WD_BIT) << pkru_pkey_bits));
}

static inline u16 pte_flags_pkey(unsigned long pte_flags)
diff --git a/arch/x86/include/asm/pkeys.h b/arch/x86/include/asm/pkeys.h
index 2ff9b98812b7..be8b3e448f76 100644
--- a/arch/x86/include/asm/pkeys.h
+++ b/arch/x86/include/asm/pkeys.h
@@ -2,6 +2,8 @@
#ifndef _ASM_X86_PKEYS_H
#define _ASM_X86_PKEYS_H

+#include <asm/pkeys_internal.h>
+
#define ARCH_DEFAULT_PKEY 0

/*
diff --git a/arch/x86/include/asm/pkeys_internal.h b/arch/x86/include/asm/pkeys_internal.h
new file mode 100644
index 000000000000..a9f086f1e4b4
--- /dev/null
+++ b/arch/x86/include/asm/pkeys_internal.h
@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_PKEYS_INTERNAL_H
+#define _ASM_X86_PKEYS_INTERNAL_H
+
+#define PKR_AD_BIT 0x1
+#define PKR_WD_BIT 0x2
+#define PKR_BITS_PER_PKEY 2
+
+#define PKR_AD_KEY(pkey) (PKR_AD_BIT << ((pkey) * PKR_BITS_PER_PKEY))
+
+#endif /*_ASM_X86_PKEYS_INTERNAL_H */
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 03b7c4ca425a..7da9855b5068 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -27,6 +27,7 @@ struct vm86;
#include <asm/unwind_hints.h>
#include <asm/vmxfeatures.h>
#include <asm/vdso/processor.h>
+#include <asm/pkeys_internal.h>

#include <linux/personality.h>
#include <linux/cache.h>
diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
index bda2e5eaca0e..fc1ec2986e03 100644
--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c
@@ -955,7 +955,7 @@ int arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
unsigned long init_val)
{
u32 old_pkru;
- int pkey_shift = (pkey * PKRU_BITS_PER_PKEY);
+ int pkey_shift = (pkey * PKR_BITS_PER_PKEY);
u32 new_pkru_bits = 0;

/*
@@ -974,16 +974,16 @@ int arch_set_user_pkey_access(struct task_struct *tsk, int pkey,

/* Set the bits we need in PKRU: */
if (init_val & PKEY_DISABLE_ACCESS)
- new_pkru_bits |= PKRU_AD_BIT;
+ new_pkru_bits |= PKR_AD_BIT;
if (init_val & PKEY_DISABLE_WRITE)
- new_pkru_bits |= PKRU_WD_BIT;
+ new_pkru_bits |= PKR_WD_BIT;

/* Shift the bits in to the correct place in PKRU for pkey: */
new_pkru_bits <<= pkey_shift;

/* Get old PKRU and mask off any old bits in place: */
old_pkru = read_pkru();
- old_pkru &= ~((PKRU_AD_BIT|PKRU_WD_BIT) << pkey_shift);
+ old_pkru &= ~((PKR_AD_BIT|PKR_WD_BIT) << pkey_shift);

/* Write old part along with new part: */
write_pkru(old_pkru | new_pkru_bits);
diff --git a/arch/x86/mm/pkeys.c b/arch/x86/mm/pkeys.c
index 8873ed1438a9..f5efb4007e74 100644
--- a/arch/x86/mm/pkeys.c
+++ b/arch/x86/mm/pkeys.c
@@ -111,19 +111,17 @@ int __arch_override_mprotect_pkey(struct vm_area_struct *vma, int prot, int pkey
return vma_pkey(vma);
}

-#define PKRU_AD_KEY(pkey) (PKRU_AD_BIT << ((pkey) * PKRU_BITS_PER_PKEY))
-
/*
* Make the default PKRU value (at execve() time) as restrictive
* as possible. This ensures that any threads clone()'d early
* in the process's lifetime will not accidentally get access
* to data which is pkey-protected later on.
*/
-u32 init_pkru_value = PKRU_AD_KEY( 1) | PKRU_AD_KEY( 2) | PKRU_AD_KEY( 3) |
- PKRU_AD_KEY( 4) | PKRU_AD_KEY( 5) | PKRU_AD_KEY( 6) |
- PKRU_AD_KEY( 7) | PKRU_AD_KEY( 8) | PKRU_AD_KEY( 9) |
- PKRU_AD_KEY(10) | PKRU_AD_KEY(11) | PKRU_AD_KEY(12) |
- PKRU_AD_KEY(13) | PKRU_AD_KEY(14) | PKRU_AD_KEY(15);
+u32 init_pkru_value = PKR_AD_KEY( 1) | PKR_AD_KEY( 2) | PKR_AD_KEY( 3) |
+ PKR_AD_KEY( 4) | PKR_AD_KEY( 5) | PKR_AD_KEY( 6) |
+ PKR_AD_KEY( 7) | PKR_AD_KEY( 8) | PKR_AD_KEY( 9) |
+ PKR_AD_KEY(10) | PKR_AD_KEY(11) | PKR_AD_KEY(12) |
+ PKR_AD_KEY(13) | PKR_AD_KEY(14) | PKR_AD_KEY(15);

/*
* Called from the FPU code when creating a fresh set of FPU
@@ -173,7 +171,7 @@ static ssize_t init_pkru_write_file(struct file *file,
* up immediately if someone attempts to disable access
* or writes to pkey 0.
*/
- if (new_init_pkru & (PKRU_AD_BIT|PKRU_WD_BIT))
+ if (new_init_pkru & (PKR_AD_BIT|PKR_WD_BIT))
return -EINVAL;

WRITE_ONCE(init_pkru_value, new_init_pkru);