[PATCH v2 2/3] ioremap: Update pgtable free interfaces with addr

From: Toshi Kani <toshi.kani@hpe.com>
To: mhocko@suse.com, akpm@linux-foundation.org, tglx@linutronix.de,
	mingo@redhat.com, hpa@zytor.com
Cc: cpandya@codeaurora.org, linux-mm@kvack.org, x86@kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, Toshi Kani <toshi.kani@hpe.com>,
	stable@vger.kernel.org
Subject: [PATCH v2 2/3] ioremap: Update pgtable free interfaces with addr
Date: Tue, 15 May 2018 15:39:30 -0600	[thread overview]
Message-ID: <20180515213931.23885-3-toshi.kani@hpe.com> (raw)
In-Reply-To: <20180515213931.23885-1-toshi.kani@hpe.com>

From: Chintan Pandya <cpandya@codeaurora.org>

This patch ("mm/vmalloc: Add interfaces to free unmapped
page table") adds following 2 interfaces to free the page
table in case we implement huge mapping.

pud_free_pmd_page() and pmd_free_pte_page()

Some architectures (like arm64) needs to do proper TLB
maintanance after updating pagetable entry even in map.
Why ? Read this,
https://patchwork.kernel.org/patch/10134581/

Pass 'addr' in these interfaces so that proper TLB ops
can be performed.

Fixes: 28ee90fe6048 ("x86/mm: implement free pmd/pte page interfaces")
Signed-off-by: Chintan Pandya <cpandya@codeaurora.org>
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Cc: <stable@vger.kernel.org>
---
 arch/arm64/mm/mmu.c           |    4 ++--
 arch/x86/mm/pgtable.c         |    8 +++++---
 include/asm-generic/pgtable.h |    8 ++++----
 lib/ioremap.c                 |    4 ++--
 4 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 2dbb2c9f1ec1..da98828609a1 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -973,12 +973,12 @@ int pmd_clear_huge(pmd_t *pmdp)
 	return 1;
 }
 
-int pud_free_pmd_page(pud_t *pud)
+int pud_free_pmd_page(pud_t *pud, unsigned long addr)
 {
 	return pud_none(*pud);
 }
 
-int pmd_free_pte_page(pmd_t *pmd)
+int pmd_free_pte_page(pmd_t *pmd, unsigned long addr)
 {
 	return pmd_none(*pmd);
 }
diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
index 08cdd7c13619..f60fdf411103 100644
--- a/arch/x86/mm/pgtable.c
+++ b/arch/x86/mm/pgtable.c
@@ -719,11 +719,12 @@ int pmd_clear_huge(pmd_t *pmd)
 /**
  * pud_free_pmd_page - Clear pud entry and free pmd page.
  * @pud: Pointer to a PUD.
+ * @addr: Virtual address associated with pud.
  *
  * Context: The pud range has been unmaped and TLB purged.
  * Return: 1 if clearing the entry succeeded. 0 otherwise.
  */
-int pud_free_pmd_page(pud_t *pud)
+int pud_free_pmd_page(pud_t *pud, unsigned long addr)
 {
 	pmd_t *pmd;
 	int i;
@@ -734,7 +735,7 @@ int pud_free_pmd_page(pud_t *pud)
 	pmd = (pmd_t *)pud_page_vaddr(*pud);
 
 	for (i = 0; i < PTRS_PER_PMD; i++)
-		if (!pmd_free_pte_page(&pmd[i]))
+		if (!pmd_free_pte_page(&pmd[i], addr + (i * PMD_SIZE)))
 			return 0;
 
 	pud_clear(pud);
@@ -746,11 +747,12 @@ int pud_free_pmd_page(pud_t *pud)
 /**
  * pmd_free_pte_page - Clear pmd entry and free pte page.
  * @pmd: Pointer to a PMD.
+ * @addr: Virtual address associated with pmd.
  *
  * Context: The pmd range has been unmaped and TLB purged.
  * Return: 1 if clearing the entry succeeded. 0 otherwise.
  */
-int pmd_free_pte_page(pmd_t *pmd)
+int pmd_free_pte_page(pmd_t *pmd, unsigned long addr)
 {
 	pte_t *pte;
 
diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h
index f59639afaa39..b081794ba135 100644
--- a/include/asm-generic/pgtable.h
+++ b/include/asm-generic/pgtable.h
@@ -1019,8 +1019,8 @@ int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot);
 int pmd_set_huge(pmd_t *pmd, phys_addr_t addr, pgprot_t prot);
 int pud_clear_huge(pud_t *pud);
 int pmd_clear_huge(pmd_t *pmd);
-int pud_free_pmd_page(pud_t *pud);
-int pmd_free_pte_page(pmd_t *pmd);
+int pud_free_pmd_page(pud_t *pud, unsigned long addr);
+int pmd_free_pte_page(pmd_t *pmd, unsigned long addr);
 #else	/* !CONFIG_HAVE_ARCH_HUGE_VMAP */
 static inline int p4d_set_huge(p4d_t *p4d, phys_addr_t addr, pgprot_t prot)
 {
@@ -1046,11 +1046,11 @@ static inline int pmd_clear_huge(pmd_t *pmd)
 {
 	return 0;
 }
-static inline int pud_free_pmd_page(pud_t *pud)
+static inline int pud_free_pmd_page(pud_t *pud, unsigned long addr)
 {
 	return 0;
 }
-static inline int pmd_free_pte_page(pmd_t *pmd)
+static inline int pmd_free_pte_page(pmd_t *pmd, unsigned long addr)
 {
 	return 0;
 }
diff --git a/lib/ioremap.c b/lib/ioremap.c
index 54e5bbaa3200..517f5853ffed 100644
--- a/lib/ioremap.c
+++ b/lib/ioremap.c
@@ -92,7 +92,7 @@ static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr,
 		if (ioremap_pmd_enabled() &&
 		    ((next - addr) == PMD_SIZE) &&
 		    IS_ALIGNED(phys_addr + addr, PMD_SIZE) &&
-		    pmd_free_pte_page(pmd)) {
+		    pmd_free_pte_page(pmd, addr)) {
 			if (pmd_set_huge(pmd, phys_addr + addr, prot))
 				continue;
 		}
@@ -119,7 +119,7 @@ static inline int ioremap_pud_range(p4d_t *p4d, unsigned long addr,
 		if (ioremap_pud_enabled() &&
 		    ((next - addr) == PUD_SIZE) &&
 		    IS_ALIGNED(phys_addr + addr, PUD_SIZE) &&
-		    pud_free_pmd_page(pud)) {
+		    pud_free_pmd_page(pud, addr)) {
 			if (pud_set_huge(pud, phys_addr + addr, prot))
 				continue;
 		}
