mm/vma: make vma_is_foreign() available for general use

Idea of a foreign VMA with respect to the present context is very generic.
But currently there are two identical definitions for this in powerpc and
x86 platforms.  Lets consolidate those redundant definitions while making
vma_is_foreign() available for general use later.  This should not cause
any functional change.

Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Link: http://lkml.kernel.org/r/1582782965-3274-3-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/arch/powerpc/mm/book3s64/pkeys.c b/arch/powerpc/mm/book3s64/pkeys.c
index 59e0ebbd803695f0c12aa8989a31458a65022257..07527f1ed1089fca61a577bb4d935b0332f2631a 100644 (file)
--- a/arch/powerpc/mm/book3s64/pkeys.c
+++ b/arch/powerpc/mm/book3s64/pkeys.c
@@ -381,18 +381,6 @@ bool arch_pte_access_permitted(u64 pte, bool write, bool execute)
  * So do not enforce things if the VMA is not from the current mm, or if we are
  * in a kernel thread.
  */
-static inline bool vma_is_foreign(struct vm_area_struct *vma)
-{
-       if (!current->mm)
-               return true;
-
-       /* if it is not our ->mm, it has to be foreign */
-       if (current->mm != vma->vm_mm)
-               return true;
-
-       return false;
-}
-
 bool arch_vma_access_permitted(struct vm_area_struct *vma, bool write,
                               bool execute, bool foreign)
 {

diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h
index b538d9ddee9c4e65fd44594db11503018199e1a5..4e55370e48e859ff7fb7342126f001adbcd4a471 100644 (file)
--- a/arch/x86/include/asm/mmu_context.h
+++ b/arch/x86/include/asm/mmu_context.h
@@ -213,21 +213,6 @@ static inline void arch_unmap(struct mm_struct *mm, unsigned long start,
  * So do not enforce things if the VMA is not from the current
  * mm, or if we are in a kernel thread.
  */
-static inline bool vma_is_foreign(struct vm_area_struct *vma)
-{
-       if (!current->mm)
-               return true;
-       /*
-        * Should PKRU be enforced on the access to this VMA?  If
-        * the VMA is from another process, then PKRU has no
-        * relevance and should not be enforced.
-        */
-       if (current->mm != vma->vm_mm)
-               return true;
-
-       return false;
-}
-
 static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
                bool write, bool execute, bool foreign)
 {

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 18583629d424dbff88a2251e3a6f0ba90bf290f6..083e66f8070997697a89696f49cded604c6053ae 100644 (file)
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -27,6 +27,7 @@
 #include <linux/memremap.h>
 #include <linux/overflow.h>
 #include <linux/sizes.h>
+#include <linux/sched.h>
 
 struct mempolicy;
 struct anon_vma;
@@ -543,6 +544,16 @@ static inline bool vma_is_anonymous(struct vm_area_struct *vma)
        return !vma->vm_ops;
 }
 
+static inline bool vma_is_foreign(struct vm_area_struct *vma)
+{
+       if (!current->mm)
+               return true;
+
+       if (current->mm != vma->vm_mm)
+               return true;
+
+       return false;
+}
 #ifdef CONFIG_SHMEM
 /*
  * The vma_is_shmem is not inline because it is used only by slow