[PATCH 3.16 065/131] arm: drop L_PTE_FILE and pte_file()-related helpers

From: Ben Hutchings
Date: Sat Sep 29 2018 - 17:51:09 EST


3.16.59-rc1 review patch. If anyone has any objections, please let me know.

------------------

From: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx>

commit b007ea798f5c568d3f464d37288220ef570f062c upstream.

We've replaced remap_file_pages(2) implementation with emulation. Nobody
creates non-linear mapping anymore.

This patch also adjust __SWP_TYPE_SHIFT, effectively increase size of
possible swap file to 128G.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Russell King <linux@xxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
arch/arm/include/asm/pgtable-2level.h | 1 -
arch/arm/include/asm/pgtable-3level.h | 1 -
arch/arm/include/asm/pgtable-nommu.h | 2 --
arch/arm/include/asm/pgtable.h | 20 +++-----------------
arch/arm/mm/proc-macros.S | 2 +-
5 files changed, 4 insertions(+), 22 deletions(-)

--- a/arch/arm/include/asm/pgtable-2level.h
+++ b/arch/arm/include/asm/pgtable-2level.h
@@ -118,7 +118,6 @@
#define L_PTE_VALID (_AT(pteval_t, 1) << 0) /* Valid */
#define L_PTE_PRESENT (_AT(pteval_t, 1) << 0)
#define L_PTE_YOUNG (_AT(pteval_t, 1) << 1)
-#define L_PTE_FILE (_AT(pteval_t, 1) << 2) /* only when !PRESENT */
#define L_PTE_DIRTY (_AT(pteval_t, 1) << 6)
#define L_PTE_RDONLY (_AT(pteval_t, 1) << 7)
#define L_PTE_USER (_AT(pteval_t, 1) << 8)
--- a/arch/arm/include/asm/pgtable-3level.h
+++ b/arch/arm/include/asm/pgtable-3level.h
@@ -77,7 +77,6 @@
*/
#define L_PTE_VALID (_AT(pteval_t, 1) << 0) /* Valid */
#define L_PTE_PRESENT (_AT(pteval_t, 3) << 0) /* Present */
-#define L_PTE_FILE (_AT(pteval_t, 1) << 2) /* only when !PRESENT */
#define L_PTE_USER (_AT(pteval_t, 1) << 6) /* AP[1] */
#define L_PTE_SHARED (_AT(pteval_t, 3) << 8) /* SH[1:0], inner shareable */
#define L_PTE_YOUNG (_AT(pteval_t, 1) << 10) /* AF */
--- a/arch/arm/include/asm/pgtable-nommu.h
+++ b/arch/arm/include/asm/pgtable-nommu.h
@@ -54,8 +54,6 @@

typedef pte_t *pte_addr_t;

-static inline int pte_file(pte_t pte) { return 0; }
-
/*
* ZERO_PAGE is a global shared page that is always zero: used
* for zero-mapped memory areas etc..
--- a/arch/arm/include/asm/pgtable.h
+++ b/arch/arm/include/asm/pgtable.h
@@ -279,12 +279,12 @@ static inline pte_t pte_modify(pte_t pte
*
* 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
* 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
- * <--------------- offset ----------------------> < type -> 0 0 0
+ * <--------------- offset ------------------------> < type -> 0 0
*
- * This gives us up to 31 swap files and 64GB per swap file. Note that
+ * This gives us up to 31 swap files and 128GB per swap file. Note that
* the offset field is always non-zero.
*/
-#define __SWP_TYPE_SHIFT 3
+#define __SWP_TYPE_SHIFT 2
#define __SWP_TYPE_BITS 5
#define __SWP_TYPE_MASK ((1 << __SWP_TYPE_BITS) - 1)
#define __SWP_OFFSET_SHIFT (__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
@@ -303,20 +303,6 @@ static inline pte_t pte_modify(pte_t pte
*/
#define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)

-/*
- * Encode and decode a file entry. File entries are stored in the Linux
- * page tables as follows:
- *
- * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
- * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
- * <----------------------- offset ------------------------> 1 0 0
- */
-#define pte_file(pte) (pte_val(pte) & L_PTE_FILE)
-#define pte_to_pgoff(x) (pte_val(x) >> 3)
-#define pgoff_to_pte(x) __pte(((x) << 3) | L_PTE_FILE)
-
-#define PTE_FILE_MAX_BITS 29
-
/* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
/* FIXME: this is not correct */
#define kern_addr_valid(addr) (1)
--- a/arch/arm/mm/proc-macros.S
+++ b/arch/arm/mm/proc-macros.S
@@ -98,7 +98,7 @@
#endif
#if !defined (CONFIG_ARM_LPAE) && \
(L_PTE_XN+L_PTE_USER+L_PTE_RDONLY+L_PTE_DIRTY+L_PTE_YOUNG+\
- L_PTE_FILE+L_PTE_PRESENT) > L_PTE_SHARED
+ L_PTE_PRESENT) > L_PTE_SHARED
#error Invalid Linux PTE bit settings
#endif
#endif /* CONFIG_MMU */