mm: consolidate pte_index() and pte_offset_*() definitions

All architectures define pte_index() as

	(address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)

and all architectures define pte_offset_kernel() as an entry in the array
of PTEs indexed by the pte_index().

For the most architectures the pte_offset_kernel() implementation relies
on the availability of pmd_page_vaddr() that converts a PMD entry value to
the virtual address of the page containing PTEs array.

Let's move x86 definitions of the PTE accessors to the generic place in
<linux/pgtable.h> and then simply drop the respective definitions from the
other architectures.

The architectures that didn't provide pmd_page_vaddr() are updated to have
that defined.

The generic implementation of pte_offset_kernel() can be overridden by an
architecture and alpha makes use of this because it has special ordering
requirements for its version of pte_offset_kernel().

[rppt@linux.ibm.com: v2]
  Link: http://lkml.kernel.org/r/20200514170327.31389-11-rppt@kernel.org
[rppt@linux.ibm.com: update]
  Link: http://lkml.kernel.org/r/20200514170327.31389-12-rppt@kernel.org
[rppt@linux.ibm.com: update]
  Link: http://lkml.kernel.org/r/20200514170327.31389-13-rppt@kernel.org
[akpm@linux-foundation.org: fix x86 warning]
[sfr@canb.auug.org.au: fix powerpc build]
  Link: http://lkml.kernel.org/r/20200607153443.GB738695@linux.ibm.com

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-10-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 18 deletions

diff --git a/arch/nios2/include/asm/pgtable.h b/arch/nios2/include/asm/pgtable.h
index f0d4921d05ad..2600d76c310c 100644
--- a/arch/nios2/include/asm/pgtable.h
+++ b/arch/nios2/include/asm/pgtable.h
@@ -102,10 +102,6 @@ static inline void set_pmd(pmd_t *pmdptr, pmd_t pmdval)
 	*pmdptr = pmdval;
 }
 
-/* to find an entry in a page-table-directory */
-#define pgd_index(addr)		(((addr) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1))
-#define pgd_offset(mm, addr)	((mm)->pgd + pgd_index(addr))
-
 static inline int pte_write(pte_t pte)		\
 	{ return pte_val(pte) & _PAGE_WRITE; }
 static inline int pte_dirty(pte_t pte)		\
@@ -236,27 +232,17 @@ static inline void pte_clear(struct mm_struct *mm,
  */
 #define mk_pte(page, prot)	(pfn_pte(page_to_pfn(page), prot))
 
-#define pte_unmap(pte)	do { } while (0)
-
 /*
  * Conversion functions: convert a page and protection to a page entry,
  * and a page entry and page directory to the page they refer to.
  */
 #define pmd_phys(pmd)		virt_to_phys((void *)pmd_val(pmd))
 #define pmd_page(pmd)		(pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT))
-#define pmd_page_vaddr(pmd)	pmd_val(pmd)
-
-#define pte_offset_map(dir, addr)			\
-	((pte_t *) page_address(pmd_page(*dir)) +	\
-	 (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)))
 
-/* to find an entry in a kernel page-table-directory */
-#define pgd_offset_k(addr)	pgd_offset(&init_mm, addr)
-
-/* Get the address to the PTE for a vaddr in specific directory */
-#define pte_offset_kernel(dir, addr)			\
-	((pte_t *) pmd_page_vaddr(*(dir)) +		\
-	 (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)))
+static inline unsigned long pmd_page_vaddr(pmd_t pmd)
+{
+	return pmd_val(pmd);
+}
 
 #define pte_ERROR(e) \
 	pr_err("%s:%d: bad pte %08lx.\n", \