[PATCH V7 01/26] mm/mmap: Build protect protection_map[] with __P000

Anshuman Khandual anshuman.khandual at arm.com
Mon Jul 11 00:05:35 PDT 2022


Build protect generic protection_map[] array with __P000, so that it can be
moved inside all the platforms one after the other. Otherwise there will be
build failures during this process. CONFIG_ARCH_HAS_VM_GET_PAGE_PROT cannot
be used for this purpose as only certain platforms enable this config now.

Cc: Andrew Morton <akpm at linux-foundation.org>
Cc: linux-mm at kvack.org
Cc: linux-kernel at vger.kernel.org
Reviewed-by: Christoph Hellwig <hch at lst.de>
Reviewed-by: Christophe Leroy <christophe.leroy at csgroup.eu>
Suggested-by: Christophe Leroy <christophe.leroy at csgroup.eu>
Signed-off-by: Anshuman Khandual <anshuman.khandual at arm.com>
---
 include/linux/mm.h | 2 ++
 mm/mmap.c          | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index cf3d0d673f6b..0ff0a1bad091 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -424,7 +424,9 @@ extern unsigned int kobjsize(const void *objp);
  * mapping from the currently active vm_flags protection bits (the
  * low four bits) to a page protection mask..
  */
+#ifdef __P000
 extern pgprot_t protection_map[16];
+#endif
 
 /*
  * The default fault flags that should be used by most of the
diff --git a/mm/mmap.c b/mm/mmap.c
index 61e6135c54ef..b01f0280bda2 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -101,6 +101,7 @@ static void unmap_region(struct mm_struct *mm,
  *								w: (no) no
  *								x: (yes) yes
  */
+#ifdef __P000
 pgprot_t protection_map[16] __ro_after_init = {
 	[VM_NONE]					= __P000,
 	[VM_READ]					= __P001,
@@ -119,6 +120,7 @@ pgprot_t protection_map[16] __ro_after_init = {
 	[VM_SHARED | VM_EXEC | VM_WRITE]		= __S110,
 	[VM_SHARED | VM_EXEC | VM_WRITE | VM_READ]	= __S111
 };
+#endif
 
 #ifndef CONFIG_ARCH_HAS_VM_GET_PAGE_PROT
 pgprot_t vm_get_page_prot(unsigned long vm_flags)
-- 
2.25.1




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