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>

2 files changed, 5 insertions, 29 deletions

diff --git a/arch/parisc/include/asm/pgtable.h b/arch/parisc/include/asm/pgtable.h
index 0b98af5fbebe..75cf84070fc9 100644
--- a/arch/parisc/include/asm/pgtable.h
+++ b/arch/parisc/include/asm/pgtable.h
@@ -427,40 +427,16 @@ static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 
 #define pte_page(pte)		(pfn_to_page(pte_pfn(pte)))
 
-#define pmd_page_vaddr(pmd)	((unsigned long) __va(pmd_address(pmd)))
+static inline unsigned long pmd_page_vaddr(pmd_t pmd)
+{
+	return ((unsigned long) __va(pmd_address(pmd)));
+}
 
 #define __pmd_page(pmd) ((unsigned long) __va(pmd_address(pmd)))
 #define pmd_page(pmd)	virt_to_page((void *)__pmd_page(pmd))
 
-#define pgd_index(address) ((address) >> PGDIR_SHIFT)
-
-/* to find an entry in a page-table-directory */
-#define pgd_offset(mm, address) \
-((mm)->pgd + ((address) >> PGDIR_SHIFT))
-
-/* 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.. */
 
-#if CONFIG_PGTABLE_LEVELS == 3
-#define pmd_index(addr)         (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))
-#define pmd_offset(dir,address) \
-((pmd_t *) pud_page_vaddr(*(dir)) + pmd_index(address))
-#else
-#define pmd_offset(dir,addr) ((pmd_t *) dir)
-#endif
-
-/* Find an entry in the third-level page table.. */ 
-#define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE-1))
-#define pte_offset_kernel(pmd, address) \
-	((pte_t *) pmd_page_vaddr(*(pmd)) + pte_index(address))
-#define pte_offset_map(pmd, address) pte_offset_kernel(pmd, address)
-#define pte_unmap(pte) do { } while (0)
-
-#define pte_unmap(pte)			do { } while (0)
-#define pte_unmap_nested(pte)		do { } while (0)
-
 extern void paging_init (void);
 
 /* Used for deferring calls to flush_dcache_page() */
diff --git a/arch/parisc/kernel/pci-dma.c b/arch/parisc/kernel/pci-dma.c
index 0f1b460ee715..70cd24bdcfec 100644
--- a/arch/parisc/kernel/pci-dma.c
+++ b/arch/parisc/kernel/pci-dma.c
@@ -201,7 +201,7 @@ static inline void unmap_uncached_pmd(pgd_t * dir, unsigned long vaddr,
 		pgd_clear(dir);
 		return;
 	}
-	pmd = pmd_offset(dir, vaddr);
+	pmd = pmd_offset(pud_offset(p4d_offset(dir, vaddr), vaddr), vaddr);
 	vaddr &= ~PGDIR_MASK;
 	end = vaddr + size;
 	if (end > PGDIR_SIZE)