riscv: switch to generic version of pte allocation

The only difference between the generic and RISC-V implementation of PTE
allocation is the usage of __GFP_RETRY_MAYFAIL for both kernel and user
PTEs and the absence of __GFP_ACCOUNT for the user PTEs.

The conversion to the generic version removes the __GFP_RETRY_MAYFAIL and
ensures that GFP_ACCOUNT is used for the user PTE allocations.

The pte_free() and pte_free_kernel() versions are identical to the generic
ones and can be simply dropped.

Link: http://lkml.kernel.org/r/1557296232-15361-13-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Guo Ren <ren_guo@c-sky.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sam Creasey <sammy@sammy.net>
Cc: Vincent Chen <deanbo422@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/riscv/include/asm/pgalloc.h

@@ -10,6 +10,8 @@
 #include <linux/mm.h>
 #include <asm/tlb.h>
 
+#include <asm-generic/pgalloc.h>	/* for pte_{alloc,free}_one */
+
 static inline void pmd_populate_kernel(struct mm_struct *mm,
 	pmd_t *pmd, pte_t *pte)
 {
@@ -74,33 +76,6 @@ static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
 
 #endif /* __PAGETABLE_PMD_FOLDED */
 
-static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm)
-{
-	return (pte_t *)__get_free_page(
-		GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_ZERO);
-}
-
-static inline struct page *pte_alloc_one(struct mm_struct *mm)
-{
-	struct page *pte;
-
-	pte = alloc_page(GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_ZERO);
-	if (likely(pte != NULL))
-		pgtable_page_ctor(pte);
-	return pte;
-}
-
-static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
-{
-	free_page((unsigned long)pte);
-}
-
-static inline void pte_free(struct mm_struct *mm, pgtable_t pte)
-{
-	pgtable_page_dtor(pte);
-	__free_page(pte);
-}
-
 #define __pte_free_tlb(tlb, pte, buf)   \
 do {                                    \
 	pgtable_page_dtor(pte);         \