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, 11 insertions, 11 deletions

diff --git a/arch/mips/kvm/mmu.c b/arch/mips/kvm/mmu.c
index 7dad7a293eae..49bd160f4d85 100644
--- a/arch/mips/kvm/mmu.c
+++ b/arch/mips/kvm/mmu.c
@@ -168,7 +168,7 @@ static pte_t *kvm_mips_walk_pgd(pgd_t *pgd, struct kvm_mmu_memory_cache *cache,
 		clear_page(new_pte);
 		pmd_populate_kernel(NULL, pmd, new_pte);
 	}
-	return pte_offset(pmd, addr);
+	return pte_offset_kernel(pmd, addr);
 }
 
 /* Caller must hold kvm->mm_lock */
@@ -187,8 +187,8 @@ static pte_t *kvm_mips_pte_for_gpa(struct kvm *kvm,
 static bool kvm_mips_flush_gpa_pte(pte_t *pte, unsigned long start_gpa,
 				   unsigned long end_gpa)
 {
-	int i_min = __pte_offset(start_gpa);
-	int i_max = __pte_offset(end_gpa);
+	int i_min = pte_index(start_gpa);
+	int i_max = pte_index(end_gpa);
 	bool safe_to_remove = (i_min == 0 && i_max == PTRS_PER_PTE - 1);
 	int i;
 
@@ -215,7 +215,7 @@ static bool kvm_mips_flush_gpa_pmd(pmd_t *pmd, unsigned long start_gpa,
 		if (!pmd_present(pmd[i]))
 			continue;
 
-		pte = pte_offset(pmd + i, 0);
+		pte = pte_offset_kernel(pmd + i, 0);
 		if (i == i_max)
 			end = end_gpa;
 
@@ -312,8 +312,8 @@ static int kvm_mips_##name##_pte(pte_t *pte, unsigned long start,	\
 				 unsigned long end)			\
 {									\
 	int ret = 0;							\
-	int i_min = __pte_offset(start);				\
-	int i_max = __pte_offset(end);					\
+	int i_min = pte_index(start);				\
+	int i_max = pte_index(end);					\
 	int i;								\
 	pte_t old, new;							\
 									\
@@ -346,7 +346,7 @@ static int kvm_mips_##name##_pmd(pmd_t *pmd, unsigned long start,	\
 		if (!pmd_present(pmd[i]))				\
 			continue;					\
 									\
-		pte = pte_offset(pmd + i, 0);				\
+		pte = pte_offset_kernel(pmd + i, 0);				\
 		if (i == i_max)						\
 			cur_end = end;					\
 									\
@@ -842,8 +842,8 @@ void kvm_trap_emul_invalidate_gva(struct kvm_vcpu *vcpu, unsigned long addr,
 static bool kvm_mips_flush_gva_pte(pte_t *pte, unsigned long start_gva,
 				   unsigned long end_gva)
 {
-	int i_min = __pte_offset(start_gva);
-	int i_max = __pte_offset(end_gva);
+	int i_min = pte_index(start_gva);
+	int i_max = pte_index(end_gva);
 	bool safe_to_remove = (i_min == 0 && i_max == PTRS_PER_PTE - 1);
 	int i;
 
@@ -877,7 +877,7 @@ static bool kvm_mips_flush_gva_pmd(pmd_t *pmd, unsigned long start_gva,
 		if (!pmd_present(pmd[i]))
 			continue;
 
-		pte = pte_offset(pmd + i, 0);
+		pte = pte_offset_kernel(pmd + i, 0);
 		if (i == i_max)
 			end = end_gva;
 
diff --git a/arch/mips/kvm/trap_emul.c b/arch/mips/kvm/trap_emul.c
index 5a11e83dffe6..60763efa723e 100644
--- a/arch/mips/kvm/trap_emul.c
+++ b/arch/mips/kvm/trap_emul.c
@@ -594,7 +594,7 @@ static void kvm_mips_emul_free_gva_pt(pgd_t *pgd)
 				pmd_va = pud_va | (k << PMD_SHIFT);
 				if (pmd_va >= end)
 					break;
-				pte = pte_offset(pmd + k, 0);
+				pte = pte_offset_kernel(pmd + k, 0);
 				pte_free_kernel(NULL, pte);
 			}
 			pmd_free(NULL, pmd);