[RFC PATCH v2 11/19] mm/sparsemem: Use alloc_table() for table allocations

From: Rick Edgecombe <rick.p.edgecombe@intel.com>
To: dave.hansen@intel.com, luto@kernel.org, peterz@infradead.org,
	x86@kernel.org, akpm@linux-foundation.org, keescook@chromium.org,
	shakeelb@google.com, vbabka@suse.cz, rppt@kernel.org
Cc: Rick Edgecombe <rick.p.edgecombe@intel.com>,
	linux-mm@kvack.org, linux-hardening@vger.kernel.org,
	kernel-hardening@lists.openwall.com, ira.weiny@intel.com,
	dan.j.williams@intel.com, linux-kernel@vger.kernel.org
Subject: [RFC PATCH v2 11/19] mm/sparsemem: Use alloc_table() for table allocations
Date: Mon, 30 Aug 2021 16:59:19 -0700	[thread overview]
Message-ID: <20210830235927.6443-12-rick.p.edgecombe@intel.com> (raw)
In-Reply-To: <20210830235927.6443-1-rick.p.edgecombe@intel.com>

In order to support allocating PKS protected page tables for vmememap,
create a new variant of alloc_table(), alloc_table_node() that allows for
allocation of tables from a specific node. Use it when possible for
allocating vmemmap tables.

vmemmap_alloc_block_zero() is currently only used to allocate page
tables, so fold it into a new function, vmemem_alloc_table() that can
be free to call alloc_table_node(). Since it is today only called with
PAGE_SIZE size, drop the size argument.

Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
---
 arch/x86/mm/pgtable.c         | 10 +++++++---
 include/asm-generic/pgalloc.h |  2 ++
 include/linux/mm.h            |  5 +++++
 mm/sparse-vmemmap.c           | 22 +++++++++++++++-------
 4 files changed, 29 insertions(+), 10 deletions(-)

diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
index e65d69ad6e0c..006dc4f81f6d 100644
--- a/arch/x86/mm/pgtable.c
+++ b/arch/x86/mm/pgtable.c
@@ -41,7 +41,7 @@ static struct grouped_page_cache gpc_pks;
 static bool __ro_after_init pks_tables_inited_val;
 
 
-struct page *alloc_table(gfp_t gfp)
+struct page *alloc_table_node(gfp_t gfp, int node)
 {
 	struct page *table;
 
@@ -53,9 +53,9 @@ struct page *alloc_table(gfp_t gfp)
 	}
 
 	if (gfp & GFP_ATOMIC)
-		table = get_grouped_page_atomic(numa_node_id(), &gpc_pks);
+		table = get_grouped_page_atomic(node, &gpc_pks);
 	else
-		table = get_grouped_page(numa_node_id(), &gpc_pks);
+		table = get_grouped_page(node, &gpc_pks);
 	if (!table)
 		return NULL;
 	__SetPageTable(table);
@@ -72,6 +72,10 @@ struct page *alloc_table(gfp_t gfp)
 
 	return table;
 }
+struct page *alloc_table(gfp_t gfp)
+{
+	return alloc_table_node(gfp, numa_node_id());
+}
 
 void free_table(struct page *table_page)
 {
diff --git a/include/asm-generic/pgalloc.h b/include/asm-generic/pgalloc.h
index e576c19abc8c..eb08371db211 100644
--- a/include/asm-generic/pgalloc.h
+++ b/include/asm-generic/pgalloc.h
@@ -14,8 +14,10 @@ static inline struct page *alloc_table(gfp_t gfp)
 {
 	return alloc_page(gfp);
 }
+/* alloc_table_node() stub defined in mm.h */
 #else /* __HAVE_ARCH_ALLOC_TABLE */
 extern struct page *alloc_table(gfp_t gfp);
+extern struct page *alloc_table_node(gfp_t gfp, int node);
 #endif /* __HAVE_ARCH_ALLOC_TABLE */
 
 #ifdef __HAVE_ARCH_FREE_TABLE
diff --git a/include/linux/mm.h b/include/linux/mm.h
index ab63d5a201cb..fdb33bc6bba8 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2332,6 +2332,11 @@ static inline void free_table(struct page *table_page)
 {
 	__free_pages(table_page, 0);
 }
+
+static inline struct page *alloc_table_node(gfp_t gfp, int node)
+{
+	return alloc_pages_node(node, gfp, 0);
+}
 #endif /* CONFIG_PKS_PG_TABLES */
 
 static inline void pgtable_init(void)
diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c
index bdce883f9286..4f479c75cc8d 100644
--- a/mm/sparse-vmemmap.c
+++ b/mm/sparse-vmemmap.c
@@ -511,13 +511,21 @@ pte_t * __meminit vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node,
 	return pte;
 }
 
-static void * __meminit vmemmap_alloc_block_zero(unsigned long size, int node)
+static void * __meminit vmemmap_alloc_table(int node)
 {
-	void *p = vmemmap_alloc_block(size, node);
+	void *p;
+	if (slab_is_available()) {
+		struct page *page = alloc_table_node(GFP_KERNEL | __GFP_ZERO, node);
+
+		if (!page)
+			return NULL;
+		return page_address(page);
+	}
 
+	p = __earlyonly_bootmem_alloc(node, PAGE_SIZE, PAGE_SIZE, __pa(MAX_DMA_ADDRESS));
 	if (!p)
 		return NULL;
-	memset(p, 0, size);
+	memset(p, 0, PAGE_SIZE);
 
 	return p;
 }
@@ -526,7 +534,7 @@ pmd_t * __meminit vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node)
 {
 	pmd_t *pmd = pmd_offset(pud, addr);
 	if (pmd_none(*pmd)) {
-		void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
+		void *p = vmemmap_alloc_table(node);
 		if (!p)
 			return NULL;
 		pmd_populate_kernel(&init_mm, pmd, p);
@@ -538,7 +546,7 @@ pud_t * __meminit vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node)
 {
 	pud_t *pud = pud_offset(p4d, addr);
 	if (pud_none(*pud)) {
-		void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
+		void *p = vmemmap_alloc_table(node);
 		if (!p)
 			return NULL;
 		pud_populate(&init_mm, pud, p);
@@ -550,7 +558,7 @@ p4d_t * __meminit vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node)
 {
 	p4d_t *p4d = p4d_offset(pgd, addr);
 	if (p4d_none(*p4d)) {
-		void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
+		void *p = vmemmap_alloc_table(node);
 		if (!p)
 			return NULL;
 		p4d_populate(&init_mm, p4d, p);
@@ -562,7 +570,7 @@ pgd_t * __meminit vmemmap_pgd_populate(unsigned long addr, int node)
 {
 	pgd_t *pgd = pgd_offset_k(addr);
 	if (pgd_none(*pgd)) {
-		void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
+		void *p = vmemmap_alloc_table(node);
 		if (!p)
 			return NULL;
 		pgd_populate(&init_mm, pgd, p);
-- 
2.17.1

