[PATCH v2 03/10] asm-generic: Prepare for riscv use of pud_alloc_one and pud_free

From: Alexandre Ghiti <alexandre.ghiti@canonical.com>
To: Jonathan Corbet <corbet@lwn.net>,
	Paul Walmsley <paul.walmsley@sifive.com>,
	Palmer Dabbelt <palmer@dabbelt.com>,
	Albert Ou <aou@eecs.berkeley.edu>, Zong Li <zong.li@sifive.com>,
	Anup Patel <anup@brainfault.org>,
	Atish Patra <Atish.Patra@wdc.com>, Christoph Hellwig <hch@lst.de>,
	Andrey Ryabinin <ryabinin.a.a@gmail.com>,
	Alexander Potapenko <glider@google.com>,
	Andrey Konovalov <andreyknvl@gmail.com>,
	Dmitry Vyukov <dvyukov@google.com>,
	Ard Biesheuvel <ardb@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
	Kees Cook <keescook@chromium.org>,
	Guo Ren <guoren@linux.alibaba.com>,
	Heinrich Schuchardt <heinrich.schuchardt@canonical.com>,
	Mayuresh Chitale <mchitale@ventanamicro.com>,
	linux-doc@vger.kernel.org, linux-riscv@lists.infradead.org,
	linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com,
	linux-efi@vger.kernel.org, linux-arch@vger.kernel.org
Cc: Alexandre Ghiti <alexandre.ghiti@canonical.com>
Subject: [PATCH v2 03/10] asm-generic: Prepare for riscv use of pud_alloc_one and pud_free
Date: Wed, 29 Sep 2021 16:51:06 +0200	[thread overview]
Message-ID: <20210929145113.1935778-4-alexandre.ghiti@canonical.com> (raw)
In-Reply-To: <20210929145113.1935778-1-alexandre.ghiti@canonical.com>

In the following commits, riscv will almost use the generic versions of
pud_alloc_one and pud_free but an additional check is required since those
functions are only relevant when using at least a 4-level page table, which
will be determined at runtime on riscv.

So move the content of those functions into other functions that riscv
can use without duplicating code.

Signed-off-by: Alexandre Ghiti <alexandre.ghiti@canonical.com>
---
 include/asm-generic/pgalloc.h | 24 ++++++++++++++++++------
 1 file changed, 18 insertions(+), 6 deletions(-)

diff --git a/include/asm-generic/pgalloc.h b/include/asm-generic/pgalloc.h
index 02932efad3ab..977bea16cf1b 100644
--- a/include/asm-generic/pgalloc.h
+++ b/include/asm-generic/pgalloc.h
@@ -147,6 +147,15 @@ static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
 
 #if CONFIG_PGTABLE_LEVELS > 3
 
+static inline pud_t *__pud_alloc_one(struct mm_struct *mm, unsigned long addr)
+{
+	gfp_t gfp = GFP_PGTABLE_USER;
+
+	if (mm == &init_mm)
+		gfp = GFP_PGTABLE_KERNEL;
+	return (pud_t *)get_zeroed_page(gfp);
+}
+
 #ifndef __HAVE_ARCH_PUD_ALLOC_ONE
 /**
  * pud_alloc_one - allocate a page for PUD-level page table
@@ -159,20 +168,23 @@ static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
  */
 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
 {
-	gfp_t gfp = GFP_PGTABLE_USER;
-
-	if (mm == &init_mm)
-		gfp = GFP_PGTABLE_KERNEL;
-	return (pud_t *)get_zeroed_page(gfp);
+	return __pud_alloc_one(mm, addr);
 }
 #endif
 
-static inline void pud_free(struct mm_struct *mm, pud_t *pud)
+static inline void __pud_free(struct mm_struct *mm, pud_t *pud)
 {
 	BUG_ON((unsigned long)pud & (PAGE_SIZE-1));
 	free_page((unsigned long)pud);
 }
 
+#ifndef __HAVE_ARCH_PUD_FREE
+static inline void pud_free(struct mm_struct *mm, pud_t *pud)
+{
+	__pud_free(mm, pud);
+}
+#endif
+
 #endif /* CONFIG_PGTABLE_LEVELS > 3 */
 
 #ifndef __HAVE_ARCH_PGD_FREE
-- 
2.30.2

