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, 7 insertions, 25 deletions

diff --git a/arch/sparc/include/asm/pgtable_32.h b/arch/sparc/include/asm/pgtable_32.h
index 484e3ce75881..632cdb959542 100644
--- a/arch/sparc/include/asm/pgtable_32.h
+++ b/arch/sparc/include/asm/pgtable_32.h
@@ -146,6 +146,12 @@ static inline unsigned long __pmd_page(pmd_t pmd)
 	return (unsigned long)__nocache_va(v << 4);
 }
 
+static inline unsigned long pmd_page_vaddr(pmd_t pmd)
+{
+	unsigned long v = pmd_val(pmd) & SRMMU_PTD_PMASK;
+	return (unsigned long)__nocache_va(v << 4);
+}
+
 static inline unsigned long pud_page_vaddr(pud_t pud)
 {
 	if (srmmu_device_memory(pud_val(pud))) {
@@ -315,30 +321,6 @@ static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 		pgprot_val(newprot));
 }
 
-#define pgd_index(address) ((address) >> PGDIR_SHIFT)
-
-/* to find an entry in a page-table-directory */
-#define pgd_offset(mm, address) ((mm)->pgd + pgd_index(address))
-
-/* to find an entry in a kernel page-table-directory */
-#define pgd_offset_k(address) pgd_offset(&init_mm, address)
-
-/* Find an entry in the second-level page table.. */
-static inline pmd_t *pmd_offset(pud_t * dir, unsigned long address)
-{
-	return (pmd_t *) pud_page_vaddr(*dir) +
-		((address >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
-}
-
-/* Find an entry in the third-level page table.. */
-pte_t *pte_offset_kernel(pmd_t * dir, unsigned long address);
-
-/*
- * This shortcut works on sun4m (and sun4d) because the nocache area is static.
- */
-#define pte_offset_map(d, a)		pte_offset_kernel(d,a)
-#define pte_unmap(pte)		do{}while(0)
-
 struct seq_file;
 void mmu_info(struct seq_file *m);
 
@@ -427,7 +409,7 @@ static inline int io_remap_pfn_range(struct vm_area_struct *vma,
 
 	return remap_pfn_range(vma, from, phys_base >> PAGE_SHIFT, size, prot);
 }
-#define io_remap_pfn_range io_remap_pfn_range 
+#define io_remap_pfn_range io_remap_pfn_range
 
 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
 #define ptep_set_access_flags(__vma, __address, __ptep, __entry, __dirty) \