There are many places where all basic VMA access flags (read, write, exec)
are initialized or checked against as a group. One such example is during
page fault. Existing vma_is_accessible() wrapper already creates the notion
of VMA accessibility as a group access permissions. Hence lets just create
VM_ACCESS_FLAGS (VM_READ|VM_WRITE|VM_EXEC) which will not only reduce code
duplication but also extend the VMA accessibility concept in general.

Cc: Russell King <li...@armlinux.org.uk>
CC: Catalin Marinas <catalin.mari...@arm.com>
CC: Mark Salter <msal...@redhat.com>
Cc: Nick Hu <nic...@andestech.com>
CC: Ley Foon Tan <ley.foon....@intel.com>
Cc: Michael Ellerman <m...@ellerman.id.au>
Cc: Heiko Carstens <heiko.carst...@de.ibm.com>
Cc: Yoshinori Sato <ys...@users.sourceforge.jp>
Cc: Guan Xuetao <g...@pku.edu.cn>
Cc: Dave Hansen <dave.han...@linux.intel.com>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: Rob Springer <rsprin...@google.com>
Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org>
Cc: Andrew Morton <a...@linux-foundation.org>
Cc: linux-arm-ker...@lists.infradead.org
Cc: linux-c6x-...@linux-c6x.org
Cc: nios2-...@lists.rocketboards.org
Cc: linuxppc-...@lists.ozlabs.org
Cc: linux-s...@vger.kernel.org
Cc: linux...@vger.kernel.org
Cc: de...@driverdev.osuosl.org
Cc: linux...@kvack.org
Cc: linux-ker...@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khand...@arm.com>
---
 arch/arm/mm/fault.c                  | 2 +-
 arch/arm64/mm/fault.c                | 2 +-
 arch/c6x/include/asm/processor.h     | 2 +-
 arch/nds32/mm/fault.c                | 2 +-
 arch/nios2/include/asm/processor.h   | 2 +-
 arch/powerpc/mm/book3s64/pkeys.c     | 2 +-
 arch/s390/mm/fault.c                 | 2 +-
 arch/sh/include/asm/processor_64.h   | 2 +-
 arch/unicore32/mm/fault.c            | 2 +-
 arch/x86/mm/pkeys.c                  | 2 +-
 drivers/staging/gasket/gasket_core.c | 2 +-
 include/linux/mm.h                   | 4 +++-
 mm/mmap.c                            | 4 ++--
 mm/mprotect.c                        | 7 +++----
 14 files changed, 19 insertions(+), 18 deletions(-)

diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index bd0f4821f7e1..2c71028d9d6b 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -189,7 +189,7 @@ void do_bad_area(unsigned long addr, unsigned int fsr, 
struct pt_regs *regs)
  */
 static inline bool access_error(unsigned int fsr, struct vm_area_struct *vma)
 {
-       unsigned int mask = VM_READ | VM_WRITE | VM_EXEC;
+       unsigned int mask = VM_ACCESS_FLAGS;
 
        if ((fsr & FSR_WRITE) && !(fsr & FSR_CM))
                mask = VM_WRITE;
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 85566d32958f..63f31206a12e 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -445,7 +445,7 @@ static int __kprobes do_page_fault(unsigned long addr, 
unsigned int esr,
        const struct fault_info *inf;
        struct mm_struct *mm = current->mm;
        vm_fault_t fault, major = 0;
-       unsigned long vm_flags = VM_READ | VM_WRITE | VM_EXEC;
+       unsigned long vm_flags = VM_ACCESS_FLAGS;
        unsigned int mm_flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
 
        if (kprobe_page_fault(regs, esr))
diff --git a/arch/c6x/include/asm/processor.h b/arch/c6x/include/asm/processor.h
index 1456f5e11de3..77372b8c28d7 100644
--- a/arch/c6x/include/asm/processor.h
+++ b/arch/c6x/include/asm/processor.h
@@ -57,7 +57,7 @@ struct thread_struct {
 }
 
 #define INIT_MMAP { \
-       &init_mm, 0, 0, NULL, PAGE_SHARED, VM_READ | VM_WRITE | VM_EXEC, 1, \
+       &init_mm, 0, 0, NULL, PAGE_SHARED, VM_ACCESS_FLAGS, 1, \
        NULL, NULL }
 
 #define task_pt_regs(task) \
diff --git a/arch/nds32/mm/fault.c b/arch/nds32/mm/fault.c
index 906dfb25353c..55387a31bf42 100644
--- a/arch/nds32/mm/fault.c
+++ b/arch/nds32/mm/fault.c
@@ -79,7 +79,7 @@ void do_page_fault(unsigned long entry, unsigned long addr,
        struct vm_area_struct *vma;
        int si_code;
        vm_fault_t fault;
-       unsigned int mask = VM_READ | VM_WRITE | VM_EXEC;
+       unsigned int mask = VM_ACCESS_FLAGS;
        unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
 
        error_code = error_code & (ITYPE_mskINST | ITYPE_mskETYPE);
diff --git a/arch/nios2/include/asm/processor.h 
b/arch/nios2/include/asm/processor.h
index 94bcb86f679f..fbfb3ab14cfc 100644
--- a/arch/nios2/include/asm/processor.h
+++ b/arch/nios2/include/asm/processor.h
@@ -51,7 +51,7 @@ struct thread_struct {
 };
 
 #define INIT_MMAP \
-       { &init_mm, (0), (0), __pgprot(0x0), VM_READ | VM_WRITE | VM_EXEC }
+       { &init_mm, (0), (0), __pgprot(0x0), VM_ACCESS_FLAGS }
 
 # define INIT_THREAD {                 \
        .kregs  = NULL,                 \
diff --git a/arch/powerpc/mm/book3s64/pkeys.c b/arch/powerpc/mm/book3s64/pkeys.c
index 59e0ebbd8036..11fd52b24f68 100644
--- a/arch/powerpc/mm/book3s64/pkeys.c
+++ b/arch/powerpc/mm/book3s64/pkeys.c
@@ -315,7 +315,7 @@ int __execute_only_pkey(struct mm_struct *mm)
 static inline bool vma_is_pkey_exec_only(struct vm_area_struct *vma)
 {
        /* Do this check first since the vm_flags should be hot */
-       if ((vma->vm_flags & (VM_READ | VM_WRITE | VM_EXEC)) != VM_EXEC)
+       if ((vma->vm_flags & VM_ACCESS_FLAGS) != VM_EXEC)
                return false;
 
        return (vma_pkey(vma) == vma->vm_mm->context.execute_only_pkey);
diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index 7b0bb475c166..b2cb3c0d0e1a 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -584,7 +584,7 @@ void do_dat_exception(struct pt_regs *regs)
        int access;
        vm_fault_t fault;
 
-       access = VM_READ | VM_EXEC | VM_WRITE;
+       access = VM_ACCESS_FLAGS;
        fault = do_exception(regs, access);
        if (unlikely(fault))
                do_fault_error(regs, access, fault);
diff --git a/arch/sh/include/asm/processor_64.h 
b/arch/sh/include/asm/processor_64.h
index 53efc9f51ef1..3b8187284e3f 100644
--- a/arch/sh/include/asm/processor_64.h
+++ b/arch/sh/include/asm/processor_64.h
@@ -121,7 +121,7 @@ struct thread_struct {
 };
 
 #define INIT_MMAP \
-{ &init_mm, 0, 0, NULL, PAGE_SHARED, VM_READ | VM_WRITE | VM_EXEC, 1, NULL, 
NULL }
+{ &init_mm, 0, 0, NULL, PAGE_SHARED, VM_ACCESS_FLAGS, 1, NULL, NULL }
 
 #define INIT_THREAD  {                         \
        .sp             = sizeof(init_stack) +  \
diff --git a/arch/unicore32/mm/fault.c b/arch/unicore32/mm/fault.c
index 76342de9cf8c..fc27c274d358 100644
--- a/arch/unicore32/mm/fault.c
+++ b/arch/unicore32/mm/fault.c
@@ -149,7 +149,7 @@ void do_bad_area(unsigned long addr, unsigned int fsr, 
struct pt_regs *regs)
  */
 static inline bool access_error(unsigned int fsr, struct vm_area_struct *vma)
 {
-       unsigned int mask = VM_READ | VM_WRITE | VM_EXEC;
+       unsigned int mask = VM_ACCESS_FLAGS;
 
        if (!(fsr ^ 0x12))      /* write? */
                mask = VM_WRITE;
diff --git a/arch/x86/mm/pkeys.c b/arch/x86/mm/pkeys.c
index c6f84c0b5d7a..8873ed1438a9 100644
--- a/arch/x86/mm/pkeys.c
+++ b/arch/x86/mm/pkeys.c
@@ -63,7 +63,7 @@ int __execute_only_pkey(struct mm_struct *mm)
 static inline bool vma_is_pkey_exec_only(struct vm_area_struct *vma)
 {
        /* Do this check first since the vm_flags should be hot */
-       if ((vma->vm_flags & (VM_READ | VM_WRITE | VM_EXEC)) != VM_EXEC)
+       if ((vma->vm_flags & VM_ACCESS_FLAGS) != VM_EXEC)
                return false;
        if (vma_pkey(vma) != vma->vm_mm->context.execute_only_pkey)
                return false;
diff --git a/drivers/staging/gasket/gasket_core.c 
b/drivers/staging/gasket/gasket_core.c
index be6b50f454b4..81bb7d58dc49 100644
--- a/drivers/staging/gasket/gasket_core.c
+++ b/drivers/staging/gasket/gasket_core.c
@@ -689,7 +689,7 @@ static bool gasket_mmap_has_permissions(struct gasket_dev 
*gasket_dev,
 
        /* Make sure that no wrong flags are set. */
        requested_permissions =
-               (vma->vm_flags & (VM_WRITE | VM_READ | VM_EXEC));
+               (vma->vm_flags & VM_ACCESS_FLAGS);
        if (requested_permissions & ~(bar_permissions)) {
                dev_dbg(gasket_dev->dev,
                        "Attempting to map a region with requested permissions "
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 7a764ae6ab68..525026df1e58 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -368,6 +368,8 @@ extern unsigned int kobjsize(const void *objp);
 #endif
 
 #define VM_STACK_FLAGS (VM_STACK | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT)
+#define VM_ACCESS_FLAGS (VM_READ | VM_WRITE | VM_EXEC)
+
 
 /*
  * Special vmas that are non-mergable, non-mlock()able.
@@ -558,7 +560,7 @@ static inline bool vma_is_anonymous(struct vm_area_struct 
*vma)
 
 static inline bool vma_is_accessible(struct vm_area_struct *vma)
 {
-       return vma->vm_flags & (VM_READ | VM_WRITE | VM_EXEC);
+       return vma->vm_flags & VM_ACCESS_FLAGS;
 }
 
 #ifdef CONFIG_SHMEM
diff --git a/mm/mmap.c b/mm/mmap.c
index 0d295f49b24d..f9a01763857b 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -106,7 +106,7 @@ static inline pgprot_t arch_filter_pgprot(pgprot_t prot)
 pgprot_t vm_get_page_prot(unsigned long vm_flags)
 {
        pgprot_t ret = __pgprot(pgprot_val(protection_map[vm_flags &
-                               (VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)]) |
+                               (VM_ACCESS_FLAGS | VM_SHARED)]) |
                        pgprot_val(arch_vm_get_page_prot(vm_flags)));
 
        return arch_filter_pgprot(ret);
@@ -1221,7 +1221,7 @@ static int anon_vma_compatible(struct vm_area_struct *a, 
struct vm_area_struct *
        return a->vm_end == b->vm_start &&
                mpol_equal(vma_policy(a), vma_policy(b)) &&
                a->vm_file == b->vm_file &&
-               !((a->vm_flags ^ b->vm_flags) & 
~(VM_READ|VM_WRITE|VM_EXEC|VM_SOFTDIRTY)) &&
+               !((a->vm_flags ^ b->vm_flags) & ~(VM_ACCESS_FLAGS | 
VM_SOFTDIRTY)) &&
                b->vm_pgoff == a->vm_pgoff + ((b->vm_start - a->vm_start) >> 
PAGE_SHIFT);
 }
 
diff --git a/mm/mprotect.c b/mm/mprotect.c
index 7a8e84f86831..4921a4211c6b 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -359,7 +359,7 @@ mprotect_fixup(struct vm_area_struct *vma, struct 
vm_area_struct **pprev,
         */
        if (arch_has_pfn_modify_check() &&
            (vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) &&
-           (newflags & (VM_READ|VM_WRITE|VM_EXEC)) == 0) {
+           (newflags & VM_ACCESS_FLAGS) == 0) {
                pgprot_t new_pgprot = vm_get_page_prot(newflags);
 
                error = walk_page_range(current->mm, start, end,
@@ -530,15 +530,14 @@ static int do_mprotect_pkey(unsigned long start, size_t 
len,
                 * If a permission is not passed to mprotect(), it must be
                 * cleared from the VMA.
                 */
-               mask_off_old_flags = VM_READ | VM_WRITE | VM_EXEC |
-                                       VM_FLAGS_CLEAR;
+               mask_off_old_flags = VM_ACCESS_FLAGS | VM_FLAGS_CLEAR;
 
                new_vma_pkey = arch_override_mprotect_pkey(vma, prot, pkey);
                newflags = calc_vm_prot_bits(prot, new_vma_pkey);
                newflags |= (vma->vm_flags & ~mask_off_old_flags);
 
                /* newflags >> 4 shift VM_MAY% in place of VM_% */
-               if ((newflags & ~(newflags >> 4)) & (VM_READ | VM_WRITE | 
VM_EXEC)) {
+               if ((newflags & ~(newflags >> 4)) & VM_ACCESS_FLAGS) {
                        error = -EACCES;
                        goto out;
                }
-- 
2.20.1

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