From 55ce6e23ebd159bc3d8f0a20e27503e09b5d8138 Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Fri, 29 Dec 2017 08:53:52 +0100
Subject: mm: don't export __add_pages

This function isn't used by any modules, and is only to be called
from core MM code.  This includes the calls for the add_pages wrapper
that might be inlined.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 mm/memory_hotplug.c | 1 -
 1 file changed, 1 deletion(-)

(limited to 'mm')

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index c52aa05b106c..5c6f96e6b334 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -334,7 +334,6 @@ int __ref __add_pages(int nid, unsigned long phys_start_pfn,
 out:
 	return err;
 }
-EXPORT_SYMBOL_GPL(__add_pages);
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
 /* find the smallest valid pfn in the range [start_pfn, end_pfn) */
-- 
cgit v1.2.3


From 24e6d5a59ac7d31adc0322de2d0117dfa370936f Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Fri, 29 Dec 2017 08:53:53 +0100
Subject: mm: pass the vmem_altmap to arch_add_memory and __add_pages

We can just pass this on instead of having to do a radix tree lookup
without proper locking 2 levels into the callchain.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 arch/ia64/mm/init.c            |  5 +++--
 arch/powerpc/mm/mem.c          |  5 +++--
 arch/s390/mm/init.c            |  5 +++--
 arch/sh/mm/init.c              |  5 +++--
 arch/x86/mm/init_32.c          |  5 +++--
 arch/x86/mm/init_64.c          | 11 ++++++-----
 include/linux/memory_hotplug.h | 17 ++++++++++-------
 kernel/memremap.c              |  3 ++-
 mm/hmm.c                       |  5 +++--
 mm/memory_hotplug.c            |  7 +++----
 10 files changed, 39 insertions(+), 29 deletions(-)

(limited to 'mm')

diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c
index 7af4e05bb61e..2e2e4f532204 100644
--- a/arch/ia64/mm/init.c
+++ b/arch/ia64/mm/init.c
@@ -647,13 +647,14 @@ mem_init (void)
 }
 
 #ifdef CONFIG_MEMORY_HOTPLUG
-int arch_add_memory(int nid, u64 start, u64 size, bool want_memblock)
+int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
+		bool want_memblock)
 {
 	unsigned long start_pfn = start >> PAGE_SHIFT;
 	unsigned long nr_pages = size >> PAGE_SHIFT;
 	int ret;
 
-	ret = __add_pages(nid, start_pfn, nr_pages, want_memblock);
+	ret = __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock);
 	if (ret)
 		printk("%s: Problem encountered in __add_pages() as ret=%d\n",
 		       __func__,  ret);
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index 4362b86ef84c..e670cfc2766e 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -127,7 +127,8 @@ int __weak remove_section_mapping(unsigned long start, unsigned long end)
 	return -ENODEV;
 }
 
-int arch_add_memory(int nid, u64 start, u64 size, bool want_memblock)
+int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
+		bool want_memblock)
 {
 	unsigned long start_pfn = start >> PAGE_SHIFT;
 	unsigned long nr_pages = size >> PAGE_SHIFT;
@@ -144,7 +145,7 @@ int arch_add_memory(int nid, u64 start, u64 size, bool want_memblock)
 		return -EFAULT;
 	}
 
-	return __add_pages(nid, start_pfn, nr_pages, want_memblock);
+	return __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock);
 }
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index 671535e64aba..e12c5af50cd7 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -222,7 +222,8 @@ device_initcall(s390_cma_mem_init);
 
 #endif /* CONFIG_CMA */
 
-int arch_add_memory(int nid, u64 start, u64 size, bool want_memblock)
+int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
+		bool want_memblock)
 {
 	unsigned long start_pfn = PFN_DOWN(start);
 	unsigned long size_pages = PFN_DOWN(size);
@@ -232,7 +233,7 @@ int arch_add_memory(int nid, u64 start, u64 size, bool want_memblock)
 	if (rc)
 		return rc;
 
-	rc = __add_pages(nid, start_pfn, size_pages, want_memblock);
+	rc = __add_pages(nid, start_pfn, size_pages, altmap, want_memblock);
 	if (rc)
 		vmem_remove_mapping(start, size);
 	return rc;
diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c
index afc54d593a26..552afbf55bad 100644
--- a/arch/sh/mm/init.c
+++ b/arch/sh/mm/init.c
@@ -485,14 +485,15 @@ void free_initrd_mem(unsigned long start, unsigned long end)
 #endif
 
 #ifdef CONFIG_MEMORY_HOTPLUG
-int arch_add_memory(int nid, u64 start, u64 size, bool want_memblock)
+int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
+		bool want_memblock)
 {
 	unsigned long start_pfn = PFN_DOWN(start);
 	unsigned long nr_pages = size >> PAGE_SHIFT;
 	int ret;
 
 	/* We only have ZONE_NORMAL, so this is easy.. */
-	ret = __add_pages(nid, start_pfn, nr_pages, want_memblock);
+	ret = __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock);
 	if (unlikely(ret))
 		printk("%s: Failed, __add_pages() == %d\n", __func__, ret);
 
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 135c9a7898c7..8a3091511a71 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -829,12 +829,13 @@ void __init mem_init(void)
 }
 
 #ifdef CONFIG_MEMORY_HOTPLUG
-int arch_add_memory(int nid, u64 start, u64 size, bool want_memblock)
+int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
+		bool want_memblock)
 {
 	unsigned long start_pfn = start >> PAGE_SHIFT;
 	unsigned long nr_pages = size >> PAGE_SHIFT;
 
-	return __add_pages(nid, start_pfn, nr_pages, want_memblock);
+	return __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock);
 }
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 8acdc35c2dfa..e80bb4189254 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -772,12 +772,12 @@ static void update_end_of_memory_vars(u64 start, u64 size)
 	}
 }
 
-int add_pages(int nid, unsigned long start_pfn,
-	      unsigned long nr_pages, bool want_memblock)
+int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
+		struct vmem_altmap *altmap, bool want_memblock)
 {
 	int ret;
 
-	ret = __add_pages(nid, start_pfn, nr_pages, want_memblock);
+	ret = __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock);
 	WARN_ON_ONCE(ret);
 
 	/* update max_pfn, max_low_pfn and high_memory */
@@ -787,14 +787,15 @@ int add_pages(int nid, unsigned long start_pfn,
 	return ret;
 }
 
-int arch_add_memory(int nid, u64 start, u64 size, bool want_memblock)
+int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
+		bool want_memblock)
 {
 	unsigned long start_pfn = start >> PAGE_SHIFT;
 	unsigned long nr_pages = size >> PAGE_SHIFT;
 
 	init_memory_mapping(start, start + size);
 
-	return add_pages(nid, start_pfn, nr_pages, want_memblock);
+	return add_pages(nid, start_pfn, nr_pages, altmap, want_memblock);
 }
 
 #define PAGE_INUSE 0xFD
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index 58e110aee7ab..db276afbefcc 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -13,6 +13,7 @@ struct pglist_data;
 struct mem_section;
 struct memory_block;
 struct resource;
+struct vmem_altmap;
 
 #ifdef CONFIG_MEMORY_HOTPLUG
 /*
@@ -131,18 +132,19 @@ extern int __remove_pages(struct zone *zone, unsigned long start_pfn,
 #endif /* CONFIG_MEMORY_HOTREMOVE */
 
 /* reasonably generic interface to expand the physical pages */
-extern int __add_pages(int nid, unsigned long start_pfn,
-	unsigned long nr_pages, bool want_memblock);
+extern int __add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
+		struct vmem_altmap *altmap, bool want_memblock);
 
 #ifndef CONFIG_ARCH_HAS_ADD_PAGES
 static inline int add_pages(int nid, unsigned long start_pfn,
-			    unsigned long nr_pages, bool want_memblock)
+		unsigned long nr_pages, struct vmem_altmap *altmap,
+		bool want_memblock)
 {
-	return __add_pages(nid, start_pfn, nr_pages, want_memblock);
+	return __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock);
 }
 #else /* ARCH_HAS_ADD_PAGES */
-int add_pages(int nid, unsigned long start_pfn,
-	      unsigned long nr_pages, bool want_memblock);
+int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
+		struct vmem_altmap *altmap, bool want_memblock);
 #endif /* ARCH_HAS_ADD_PAGES */
 
 #ifdef CONFIG_NUMA
@@ -318,7 +320,8 @@ extern int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn,
 		void *arg, int (*func)(struct memory_block *, void *));
 extern int add_memory(int nid, u64 start, u64 size);
 extern int add_memory_resource(int nid, struct resource *resource, bool online);
-extern int arch_add_memory(int nid, u64 start, u64 size, bool want_memblock);
+extern int arch_add_memory(int nid, u64 start, u64 size,
+		struct vmem_altmap *altmap, bool want_memblock);
 extern void move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn,
 		unsigned long nr_pages);
 extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages);
diff --git a/kernel/memremap.c b/kernel/memremap.c
index 403ab9cdb949..8488cdeead16 100644
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -382,6 +382,7 @@ void *devm_memremap_pages(struct device *dev, struct resource *res,
 	if (altmap) {
 		memcpy(&page_map->altmap, altmap, sizeof(*altmap));
 		pgmap->altmap = &page_map->altmap;
+		altmap = pgmap->altmap;
 	}
 	pgmap->ref = ref;
 	pgmap->res = &page_map->res;
@@ -427,7 +428,7 @@ void *devm_memremap_pages(struct device *dev, struct resource *res,
 		goto err_pfn_remap;
 
 	mem_hotplug_begin();
-	error = arch_add_memory(nid, align_start, align_size, false);
+	error = arch_add_memory(nid, align_start, align_size, altmap, false);
 	if (!error)
 		move_pfn_range_to_zone(&NODE_DATA(nid)->node_zones[ZONE_DEVICE],
 					align_start >> PAGE_SHIFT,
diff --git a/mm/hmm.c b/mm/hmm.c
index ea19742a5d60..231aaacd1997 100644
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -931,10 +931,11 @@ static int hmm_devmem_pages_create(struct hmm_devmem *devmem)
 	 * want the linear mapping and thus use arch_add_memory().
 	 */
 	if (devmem->pagemap.type == MEMORY_DEVICE_PUBLIC)
-		ret = arch_add_memory(nid, align_start, align_size, false);
+		ret = arch_add_memory(nid, align_start, align_size, NULL,
+				false);
 	else
 		ret = add_pages(nid, align_start >> PAGE_SHIFT,
-				align_size >> PAGE_SHIFT, false);
+				align_size >> PAGE_SHIFT, NULL, false);
 	if (ret) {
 		mem_hotplug_done();
 		goto error_add_memory;
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 5c6f96e6b334..fc0485dcece1 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -292,18 +292,17 @@ static int __meminit __add_section(int nid, unsigned long phys_start_pfn,
  * add the new pages.
  */
 int __ref __add_pages(int nid, unsigned long phys_start_pfn,
-			unsigned long nr_pages, bool want_memblock)
+		unsigned long nr_pages, struct vmem_altmap *altmap,
+		bool want_memblock)
 {
 	unsigned long i;
 	int err = 0;
 	int start_sec, end_sec;
-	struct vmem_altmap *altmap;
 
 	/* during initialize mem_map, align hot-added range to section */
 	start_sec = pfn_to_section_nr(phys_start_pfn);
 	end_sec = pfn_to_section_nr(phys_start_pfn + nr_pages - 1);
 
-	altmap = to_vmem_altmap((unsigned long) pfn_to_page(phys_start_pfn));
 	if (altmap) {
 		/*
 		 * Validate altmap is within bounds of the total request
@@ -1148,7 +1147,7 @@ int __ref add_memory_resource(int nid, struct resource *res, bool online)
 	}
 
 	/* call arch's memory hotadd */
-	ret = arch_add_memory(nid, start, size, true);
+	ret = arch_add_memory(nid, start, size, NULL, true);
 
 	if (ret < 0)
 		goto error;
-- 
cgit v1.2.3


From 7b73d978a5d0d2a3637bdd57191cb6ffbad3feca Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Fri, 29 Dec 2017 08:53:54 +0100
Subject: mm: pass the vmem_altmap to vmemmap_populate

We can just pass this on instead of having to do a radix tree lookup
without proper locking a few levels into the callchain.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 arch/arm64/mm/mmu.c            |  6 ++++--
 arch/ia64/mm/discontig.c       |  3 ++-
 arch/powerpc/mm/init_64.c      |  7 ++-----
 arch/s390/mm/vmem.c            |  3 ++-
 arch/sparc/mm/init_64.c        |  2 +-
 arch/x86/mm/init_64.c          |  4 ++--
 include/linux/memory_hotplug.h |  3 ++-
 include/linux/mm.h             |  6 ++++--
 mm/memory_hotplug.c            |  7 ++++---
 mm/sparse-vmemmap.c            |  7 ++++---
 mm/sparse.c                    | 20 ++++++++++++--------
 11 files changed, 39 insertions(+), 29 deletions(-)

(limited to 'mm')

diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 267d2b79d52d..ec8952ff13be 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -654,12 +654,14 @@ int kern_addr_valid(unsigned long addr)
 }
 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 #if !ARM64_SWAPPER_USES_SECTION_MAPS
-int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
+int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
+		struct vmem_altmap *altmap)
 {
 	return vmemmap_populate_basepages(start, end, node);
 }
 #else	/* !ARM64_SWAPPER_USES_SECTION_MAPS */
-int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
+int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
+		struct vmem_altmap *altmap)
 {
 	unsigned long addr = start;
 	unsigned long next;
diff --git a/arch/ia64/mm/discontig.c b/arch/ia64/mm/discontig.c
index 9b2d994cddf6..1555aecaaf85 100644
--- a/arch/ia64/mm/discontig.c
+++ b/arch/ia64/mm/discontig.c
@@ -754,7 +754,8 @@ void arch_refresh_nodedata(int update_node, pg_data_t *update_pgdat)
 #endif
 
 #ifdef CONFIG_SPARSEMEM_VMEMMAP
-int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
+int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
+		struct vmem_altmap *altmap)
 {
 	return vmemmap_populate_basepages(start, end, node);
 }
diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c
index a07722531b32..779b74a96b8f 100644
--- a/arch/powerpc/mm/init_64.c
+++ b/arch/powerpc/mm/init_64.c
@@ -183,7 +183,8 @@ static __meminit void vmemmap_list_populate(unsigned long phys,
 	vmemmap_list = vmem_back;
 }
 
-int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
+int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
+		struct vmem_altmap *altmap)
 {
 	unsigned long page_size = 1 << mmu_psize_defs[mmu_vmemmap_psize].shift;
 
@@ -193,16 +194,12 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
 	pr_debug("vmemmap_populate %lx..%lx, node %d\n", start, end, node);
 
 	for (; start < end; start += page_size) {
-		struct vmem_altmap *altmap;
 		void *p;
 		int rc;
 
 		if (vmemmap_populated(start, page_size))
 			continue;
 
-		/* altmap lookups only work at section boundaries */
-		altmap = to_vmem_altmap(SECTION_ALIGN_DOWN(start));
-
 		p =  __vmemmap_alloc_block_buf(page_size, node, altmap);
 		if (!p)
 			return -ENOMEM;
diff --git a/arch/s390/mm/vmem.c b/arch/s390/mm/vmem.c
index 3316d463fc29..c44ef0e7c466 100644
--- a/arch/s390/mm/vmem.c
+++ b/arch/s390/mm/vmem.c
@@ -211,7 +211,8 @@ static void vmem_remove_range(unsigned long start, unsigned long size)
 /*
  * Add a backed mem_map array to the virtual mem_map array.
  */
-int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
+int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
+		struct vmem_altmap *altmap)
 {
 	unsigned long pgt_prot, sgt_prot;
 	unsigned long address = start;
diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c
index 55ba62957e64..42d27a1a042a 100644
--- a/arch/sparc/mm/init_64.c
+++ b/arch/sparc/mm/init_64.c
@@ -2628,7 +2628,7 @@ EXPORT_SYMBOL(_PAGE_CACHE);
 
 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 int __meminit vmemmap_populate(unsigned long vstart, unsigned long vend,
-			       int node)
+			       int node, struct vmem_altmap *altmap)
 {
 	unsigned long pte_base;
 
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index e80bb4189254..594902ef56ef 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -1411,9 +1411,9 @@ static int __meminit vmemmap_populate_hugepages(unsigned long start,
 	return 0;
 }
 
-int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
+int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
+		struct vmem_altmap *altmap)
 {
-	struct vmem_altmap *altmap = to_vmem_altmap(start);
 	int err;
 
 	if (boot_cpu_has(X86_FEATURE_PSE))
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index db276afbefcc..cbdd6d52e877 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -327,7 +327,8 @@ extern void move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn,
 extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages);
 extern bool is_memblock_offlined(struct memory_block *mem);
 extern void remove_memory(int nid, u64 start, u64 size);
-extern int sparse_add_one_section(struct pglist_data *pgdat, unsigned long start_pfn);
+extern int sparse_add_one_section(struct pglist_data *pgdat,
+		unsigned long start_pfn, struct vmem_altmap *altmap);
 extern void sparse_remove_one_section(struct zone *zone, struct mem_section *ms,
 		unsigned long map_offset);
 extern struct page *sparse_decode_mem_map(unsigned long coded_mem_map,
diff --git a/include/linux/mm.h b/include/linux/mm.h
index ea818ff739cd..2f3a7ebecbe2 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2538,7 +2538,8 @@ void sparse_mem_maps_populate_node(struct page **map_map,
 				   unsigned long map_count,
 				   int nodeid);
 
-struct page *sparse_mem_map_populate(unsigned long pnum, int nid);
+struct page *sparse_mem_map_populate(unsigned long pnum, int nid,
+		struct vmem_altmap *altmap);
 pgd_t *vmemmap_pgd_populate(unsigned long addr, int node);
 p4d_t *vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node);
 pud_t *vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node);
@@ -2556,7 +2557,8 @@ static inline void *vmemmap_alloc_block_buf(unsigned long size, int node)
 void vmemmap_verify(pte_t *, int, unsigned long, unsigned long);
 int vmemmap_populate_basepages(unsigned long start, unsigned long end,
 			       int node);
-int vmemmap_populate(unsigned long start, unsigned long end, int node);
+int vmemmap_populate(unsigned long start, unsigned long end, int node,
+		struct vmem_altmap *altmap);
 void vmemmap_populate_print_last(void);
 #ifdef CONFIG_MEMORY_HOTPLUG
 void vmemmap_free(unsigned long start, unsigned long end);
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index fc0485dcece1..b36f1822c432 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -250,7 +250,7 @@ void __init register_page_bootmem_info_node(struct pglist_data *pgdat)
 #endif /* CONFIG_HAVE_BOOTMEM_INFO_NODE */
 
 static int __meminit __add_section(int nid, unsigned long phys_start_pfn,
-		bool want_memblock)
+		struct vmem_altmap *altmap, bool want_memblock)
 {
 	int ret;
 	int i;
@@ -258,7 +258,7 @@ static int __meminit __add_section(int nid, unsigned long phys_start_pfn,
 	if (pfn_valid(phys_start_pfn))
 		return -EEXIST;
 
-	ret = sparse_add_one_section(NODE_DATA(nid), phys_start_pfn);
+	ret = sparse_add_one_section(NODE_DATA(nid), phys_start_pfn, altmap);
 	if (ret < 0)
 		return ret;
 
@@ -317,7 +317,8 @@ int __ref __add_pages(int nid, unsigned long phys_start_pfn,
 	}
 
 	for (i = start_sec; i <= end_sec; i++) {
-		err = __add_section(nid, section_nr_to_pfn(i), want_memblock);
+		err = __add_section(nid, section_nr_to_pfn(i), altmap,
+				want_memblock);
 
 		/*
 		 * EEXIST is finally dealt with by ioresource collision
diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c
index 17acf01791fa..376dcf05a39c 100644
--- a/mm/sparse-vmemmap.c
+++ b/mm/sparse-vmemmap.c
@@ -278,7 +278,8 @@ int __meminit vmemmap_populate_basepages(unsigned long start,
 	return 0;
 }
 
-struct page * __meminit sparse_mem_map_populate(unsigned long pnum, int nid)
+struct page * __meminit sparse_mem_map_populate(unsigned long pnum, int nid,
+		struct vmem_altmap *altmap)
 {
 	unsigned long start;
 	unsigned long end;
@@ -288,7 +289,7 @@ struct page * __meminit sparse_mem_map_populate(unsigned long pnum, int nid)
 	start = (unsigned long)map;
 	end = (unsigned long)(map + PAGES_PER_SECTION);
 
-	if (vmemmap_populate(start, end, nid))
+	if (vmemmap_populate(start, end, nid, altmap))
 		return NULL;
 
 	return map;
@@ -318,7 +319,7 @@ void __init sparse_mem_maps_populate_node(struct page **map_map,
 		if (!present_section_nr(pnum))
 			continue;
 
-		map_map[pnum] = sparse_mem_map_populate(pnum, nodeid);
+		map_map[pnum] = sparse_mem_map_populate(pnum, nodeid, NULL);
 		if (map_map[pnum])
 			continue;
 		ms = __nr_to_section(pnum);
diff --git a/mm/sparse.c b/mm/sparse.c
index 7a5dacaa06e3..5f4a0dac7836 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -417,7 +417,8 @@ static void __init sparse_early_usemaps_alloc_node(void *data,
 }
 
 #ifndef CONFIG_SPARSEMEM_VMEMMAP
-struct page __init *sparse_mem_map_populate(unsigned long pnum, int nid)
+struct page __init *sparse_mem_map_populate(unsigned long pnum, int nid,
+		struct vmem_altmap *altmap)
 {
 	struct page *map;
 	unsigned long size;
@@ -472,7 +473,7 @@ void __init sparse_mem_maps_populate_node(struct page **map_map,
 
 		if (!present_section_nr(pnum))
 			continue;
-		map_map[pnum] = sparse_mem_map_populate(pnum, nodeid);
+		map_map[pnum] = sparse_mem_map_populate(pnum, nodeid, NULL);
 		if (map_map[pnum])
 			continue;
 		ms = __nr_to_section(pnum);
@@ -500,7 +501,7 @@ static struct page __init *sparse_early_mem_map_alloc(unsigned long pnum)
 	struct mem_section *ms = __nr_to_section(pnum);
 	int nid = sparse_early_nid(ms);
 
-	map = sparse_mem_map_populate(pnum, nid);
+	map = sparse_mem_map_populate(pnum, nid, NULL);
 	if (map)
 		return map;
 
@@ -678,10 +679,11 @@ void offline_mem_sections(unsigned long start_pfn, unsigned long end_pfn)
 #endif
 
 #ifdef CONFIG_SPARSEMEM_VMEMMAP
-static inline struct page *kmalloc_section_memmap(unsigned long pnum, int nid)
+static inline struct page *kmalloc_section_memmap(unsigned long pnum, int nid,
+		struct vmem_altmap *altmap)
 {
 	/* This will make the necessary allocations eventually. */
-	return sparse_mem_map_populate(pnum, nid);
+	return sparse_mem_map_populate(pnum, nid, altmap);
 }
 static void __kfree_section_memmap(struct page *memmap)
 {
@@ -721,7 +723,8 @@ got_map_ptr:
 	return ret;
 }
 
-static inline struct page *kmalloc_section_memmap(unsigned long pnum, int nid)
+static inline struct page *kmalloc_section_memmap(unsigned long pnum, int nid,
+		struct vmem_altmap *altmap)
 {
 	return __kmalloc_section_memmap();
 }
@@ -773,7 +776,8 @@ static void free_map_bootmem(struct page *memmap)
  * set.  If this is <=0, then that means that the passed-in
  * map was not consumed and must be freed.
  */
-int __meminit sparse_add_one_section(struct pglist_data *pgdat, unsigned long start_pfn)
+int __meminit sparse_add_one_section(struct pglist_data *pgdat,
+		unsigned long start_pfn, struct vmem_altmap *altmap)
 {
 	unsigned long section_nr = pfn_to_section_nr(start_pfn);
 	struct mem_section *ms;
@@ -789,7 +793,7 @@ int __meminit sparse_add_one_section(struct pglist_data *pgdat, unsigned long st
 	ret = sparse_index_init(section_nr, pgdat->node_id);
 	if (ret < 0 && ret != -EEXIST)
 		return ret;
-	memmap = kmalloc_section_memmap(section_nr, pgdat->node_id);
+	memmap = kmalloc_section_memmap(section_nr, pgdat->node_id, altmap);
 	if (!memmap)
 		return -ENOMEM;
 	usemap = __kmalloc_section_usemap();
-- 
cgit v1.2.3


From da024512a1fa5c979257e442130ee1d468285057 Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Fri, 29 Dec 2017 08:53:55 +0100
Subject: mm: pass the vmem_altmap to arch_remove_memory and __remove_pages

We can just pass this on instead of having to do a radix tree lookup
without proper locking 2 levels into the callchain.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 arch/ia64/mm/init.c            | 4 ++--
 arch/powerpc/mm/mem.c          | 6 ++----
 arch/s390/mm/init.c            | 2 +-
 arch/sh/mm/init.c              | 4 ++--
 arch/x86/mm/init_32.c          | 4 ++--
 arch/x86/mm/init_64.c          | 6 ++----
 include/linux/memory_hotplug.h | 5 +++--
 kernel/memremap.c              | 2 +-
 mm/hmm.c                       | 4 ++--
 mm/memory_hotplug.c            | 8 ++------
 10 files changed, 19 insertions(+), 26 deletions(-)

(limited to 'mm')

diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c
index 2e2e4f532204..6a8ce9e1536e 100644
--- a/arch/ia64/mm/init.c
+++ b/arch/ia64/mm/init.c
@@ -663,7 +663,7 @@ int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
 }
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
-int arch_remove_memory(u64 start, u64 size)
+int arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
 {
 	unsigned long start_pfn = start >> PAGE_SHIFT;
 	unsigned long nr_pages = size >> PAGE_SHIFT;
@@ -671,7 +671,7 @@ int arch_remove_memory(u64 start, u64 size)
 	int ret;
 
 	zone = page_zone(pfn_to_page(start_pfn));
-	ret = __remove_pages(zone, start_pfn, nr_pages);
+	ret = __remove_pages(zone, start_pfn, nr_pages, altmap);
 	if (ret)
 		pr_warn("%s: Problem encountered in __remove_pages() as"
 			" ret=%d\n", __func__,  ret);
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index e670cfc2766e..22aa528b78a2 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -149,11 +149,10 @@ int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
 }
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
-int arch_remove_memory(u64 start, u64 size)
+int arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
 {
 	unsigned long start_pfn = start >> PAGE_SHIFT;
 	unsigned long nr_pages = size >> PAGE_SHIFT;
-	struct vmem_altmap *altmap;
 	struct page *page;
 	int ret;
 
@@ -162,11 +161,10 @@ int arch_remove_memory(u64 start, u64 size)
 	 * when querying the zone.
 	 */
 	page = pfn_to_page(start_pfn);
-	altmap = to_vmem_altmap((unsigned long) page);
 	if (altmap)
 		page += vmem_altmap_offset(altmap);
 
-	ret = __remove_pages(page_zone(page), start_pfn, nr_pages);
+	ret = __remove_pages(page_zone(page), start_pfn, nr_pages, altmap);
 	if (ret)
 		return ret;
 
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index e12c5af50cd7..3fa3e5323612 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -240,7 +240,7 @@ int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
 }
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
-int arch_remove_memory(u64 start, u64 size)
+int arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
 {
 	/*
 	 * There is no hardware or firmware interface which could trigger a
diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c
index 552afbf55bad..ce0bbaa7e404 100644
--- a/arch/sh/mm/init.c
+++ b/arch/sh/mm/init.c
@@ -510,7 +510,7 @@ EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
 #endif
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
-int arch_remove_memory(u64 start, u64 size)
+int arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
 {
 	unsigned long start_pfn = PFN_DOWN(start);
 	unsigned long nr_pages = size >> PAGE_SHIFT;
@@ -518,7 +518,7 @@ int arch_remove_memory(u64 start, u64 size)
 	int ret;
 
 	zone = page_zone(pfn_to_page(start_pfn));
-	ret = __remove_pages(zone, start_pfn, nr_pages);
+	ret = __remove_pages(zone, start_pfn, nr_pages, altmap);
 	if (unlikely(ret))
 		pr_warn("%s: Failed, __remove_pages() == %d\n", __func__,
 			ret);
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 8a3091511a71..79cb066f40c0 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -839,14 +839,14 @@ int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
 }
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
-int arch_remove_memory(u64 start, u64 size)
+int arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
 {
 	unsigned long start_pfn = start >> PAGE_SHIFT;
 	unsigned long nr_pages = size >> PAGE_SHIFT;
 	struct zone *zone;
 
 	zone = page_zone(pfn_to_page(start_pfn));
-	return __remove_pages(zone, start_pfn, nr_pages);
+	return __remove_pages(zone, start_pfn, nr_pages, altmap);
 }
 #endif
 #endif
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 594902ef56ef..3c046618cc7e 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -1132,21 +1132,19 @@ kernel_physical_mapping_remove(unsigned long start, unsigned long end)
 	remove_pagetable(start, end, true);
 }
 
-int __ref arch_remove_memory(u64 start, u64 size)
+int __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
 {
 	unsigned long start_pfn = start >> PAGE_SHIFT;
 	unsigned long nr_pages = size >> PAGE_SHIFT;
 	struct page *page = pfn_to_page(start_pfn);
-	struct vmem_altmap *altmap;
 	struct zone *zone;
 	int ret;
 
 	/* With altmap the first mapped page is offset from @start */
-	altmap = to_vmem_altmap((unsigned long) page);
 	if (altmap)
 		page += vmem_altmap_offset(altmap);
 	zone = page_zone(page);
-	ret = __remove_pages(zone, start_pfn, nr_pages);
+	ret = __remove_pages(zone, start_pfn, nr_pages, altmap);
 	WARN_ON_ONCE(ret);
 	kernel_physical_mapping_remove(start, start + size);
 
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index cbdd6d52e877..e71927d0d46b 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -126,9 +126,10 @@ static inline bool movable_node_is_enabled(void)
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
 extern bool is_pageblock_removable_nolock(struct page *page);
-extern int arch_remove_memory(u64 start, u64 size);
+extern int arch_remove_memory(u64 start, u64 size,
+		struct vmem_altmap *altmap);
 extern int __remove_pages(struct zone *zone, unsigned long start_pfn,
-	unsigned long nr_pages);
+	unsigned long nr_pages, struct vmem_altmap *altmap);
 #endif /* CONFIG_MEMORY_HOTREMOVE */
 
 /* reasonably generic interface to expand the physical pages */
diff --git a/kernel/memremap.c b/kernel/memremap.c
index 8488cdeead16..380fca1c4a02 100644
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -304,7 +304,7 @@ static void devm_memremap_pages_release(struct device *dev, void *data)
 	align_size = ALIGN(resource_size(res), SECTION_SIZE);
 
 	mem_hotplug_begin();
-	arch_remove_memory(align_start, align_size);
+	arch_remove_memory(align_start, align_size, pgmap->altmap);
 	mem_hotplug_done();
 
 	untrack_pfn(NULL, PHYS_PFN(align_start), align_size);
diff --git a/mm/hmm.c b/mm/hmm.c
index 231aaacd1997..5d17ba89062f 100644
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -838,10 +838,10 @@ static void hmm_devmem_release(struct device *dev, void *data)
 
 	mem_hotplug_begin();
 	if (resource->desc == IORES_DESC_DEVICE_PRIVATE_MEMORY)
-		__remove_pages(zone, start_pfn, npages);
+		__remove_pages(zone, start_pfn, npages, NULL);
 	else
 		arch_remove_memory(start_pfn << PAGE_SHIFT,
-				   npages << PAGE_SHIFT);
+				   npages << PAGE_SHIFT, NULL);
 	mem_hotplug_done();
 
 	hmm_devmem_radix_release(resource);
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index b36f1822c432..eae6bf47caf7 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -569,7 +569,7 @@ static int __remove_section(struct zone *zone, struct mem_section *ms,
  * calling offline_pages().
  */
 int __remove_pages(struct zone *zone, unsigned long phys_start_pfn,
-		 unsigned long nr_pages)
+		 unsigned long nr_pages, struct vmem_altmap *altmap)
 {
 	unsigned long i;
 	unsigned long map_offset = 0;
@@ -577,10 +577,6 @@ int __remove_pages(struct zone *zone, unsigned long phys_start_pfn,
 
 	/* In the ZONE_DEVICE case device driver owns the memory region */
 	if (is_dev_zone(zone)) {
-		struct page *page = pfn_to_page(phys_start_pfn);
-		struct vmem_altmap *altmap;
-
-		altmap = to_vmem_altmap((unsigned long) page);
 		if (altmap)
 			map_offset = vmem_altmap_offset(altmap);
 	} else {
@@ -1890,7 +1886,7 @@ void __ref remove_memory(int nid, u64 start, u64 size)
 	memblock_free(start, size);
 	memblock_remove(start, size);
 
-	arch_remove_memory(start, size);
+	arch_remove_memory(start, size, NULL);
 
 	try_offline_node(nid);
 
-- 
cgit v1.2.3


From 24b6d4164348370c6b6a58b4248babd85ff9e982 Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Fri, 29 Dec 2017 08:53:56 +0100
Subject: mm: pass the vmem_altmap to vmemmap_free

We can just pass this on instead of having to do a radix tree lookup
without proper locking a few levels into the callchain.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 arch/arm64/mm/mmu.c            |  3 +-
 arch/ia64/mm/discontig.c       |  3 +-
 arch/powerpc/mm/init_64.c      |  5 ++--
 arch/s390/mm/vmem.c            |  3 +-
 arch/sparc/mm/init_64.c        |  3 +-
 arch/x86/mm/init_64.c          | 67 ++++++++++++++++++++++++------------------
 include/linux/memory_hotplug.h |  2 +-
 include/linux/mm.h             |  3 +-
 mm/memory_hotplug.c            |  7 +++--
 mm/sparse.c                    | 23 ++++++++-------
 10 files changed, 68 insertions(+), 51 deletions(-)

(limited to 'mm')

diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index ec8952ff13be..0b1f13e0b4b3 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -696,7 +696,8 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
 	return 0;
 }
 #endif	/* CONFIG_ARM64_64K_PAGES */
-void vmemmap_free(unsigned long start, unsigned long end)
+void vmemmap_free(unsigned long start, unsigned long end,
+		struct vmem_altmap *altmap)
 {
 }
 #endif	/* CONFIG_SPARSEMEM_VMEMMAP */
diff --git a/arch/ia64/mm/discontig.c b/arch/ia64/mm/discontig.c
index 1555aecaaf85..5ea0d8d0968b 100644
--- a/arch/ia64/mm/discontig.c
+++ b/arch/ia64/mm/discontig.c
@@ -760,7 +760,8 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
 	return vmemmap_populate_basepages(start, end, node);
 }
 
-void vmemmap_free(unsigned long start, unsigned long end)
+void vmemmap_free(unsigned long start, unsigned long end,
+		struct vmem_altmap *altmap)
 {
 }
 #endif
diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c
index 779b74a96b8f..db7d4e092157 100644
--- a/arch/powerpc/mm/init_64.c
+++ b/arch/powerpc/mm/init_64.c
@@ -254,7 +254,8 @@ static unsigned long vmemmap_list_free(unsigned long start)
 	return vmem_back->phys;
 }
 
-void __ref vmemmap_free(unsigned long start, unsigned long end)
+void __ref vmemmap_free(unsigned long start, unsigned long end,
+		struct vmem_altmap *altmap)
 {
 	unsigned long page_size = 1 << mmu_psize_defs[mmu_vmemmap_psize].shift;
 	unsigned long page_order = get_order(page_size);
@@ -265,7 +266,6 @@ void __ref vmemmap_free(unsigned long start, unsigned long end)
 
 	for (; start < end; start += page_size) {
 		unsigned long nr_pages, addr;
-		struct vmem_altmap *altmap;
 		struct page *section_base;
 		struct page *page;
 
@@ -285,7 +285,6 @@ void __ref vmemmap_free(unsigned long start, unsigned long end)
 		section_base = pfn_to_page(vmemmap_section_start(start));
 		nr_pages = 1 << page_order;
 
-		altmap = to_vmem_altmap((unsigned long) section_base);
 		if (altmap) {
 			vmem_altmap_free(altmap, nr_pages);
 		} else if (PageReserved(page)) {
diff --git a/arch/s390/mm/vmem.c b/arch/s390/mm/vmem.c
index c44ef0e7c466..db55561c5981 100644
--- a/arch/s390/mm/vmem.c
+++ b/arch/s390/mm/vmem.c
@@ -297,7 +297,8 @@ out:
 	return ret;
 }
 
-void vmemmap_free(unsigned long start, unsigned long end)
+void vmemmap_free(unsigned long start, unsigned long end,
+		struct vmem_altmap *altmap)
 {
 }
 
diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c
index 42d27a1a042a..995f9490334d 100644
--- a/arch/sparc/mm/init_64.c
+++ b/arch/sparc/mm/init_64.c
@@ -2671,7 +2671,8 @@ int __meminit vmemmap_populate(unsigned long vstart, unsigned long vend,
 	return 0;
 }
 
-void vmemmap_free(unsigned long start, unsigned long end)
+void vmemmap_free(unsigned long start, unsigned long end,
+		struct vmem_altmap *altmap)
 {
 }
 #endif /* CONFIG_SPARSEMEM_VMEMMAP */
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 3c046618cc7e..0cab4b5b59ba 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -800,11 +800,11 @@ int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
 
 #define PAGE_INUSE 0xFD
 
-static void __meminit free_pagetable(struct page *page, int order)
+static void __meminit free_pagetable(struct page *page, int order,
+		struct vmem_altmap *altmap)
 {
 	unsigned long magic;
 	unsigned int nr_pages = 1 << order;
-	struct vmem_altmap *altmap = to_vmem_altmap((unsigned long) page);
 
 	if (altmap) {
 		vmem_altmap_free(altmap, nr_pages);
@@ -826,7 +826,8 @@ static void __meminit free_pagetable(struct page *page, int order)
 		free_pages((unsigned long)page_address(page), order);
 }
 
-static void __meminit free_pte_table(pte_t *pte_start, pmd_t *pmd)
+static void __meminit free_pte_table(pte_t *pte_start, pmd_t *pmd,
+		struct vmem_altmap *altmap)
 {
 	pte_t *pte;
 	int i;
@@ -838,13 +839,14 @@ static void __meminit free_pte_table(pte_t *pte_start, pmd_t *pmd)
 	}
 
 	/* free a pte talbe */
-	free_pagetable(pmd_page(*pmd), 0);
+	free_pagetable(pmd_page(*pmd), 0, altmap);
 	spin_lock(&init_mm.page_table_lock);
 	pmd_clear(pmd);
 	spin_unlock(&init_mm.page_table_lock);
 }
 
-static void __meminit free_pmd_table(pmd_t *pmd_start, pud_t *pud)
+static void __meminit free_pmd_table(pmd_t *pmd_start, pud_t *pud,
+		struct vmem_altmap *altmap)
 {
 	pmd_t *pmd;
 	int i;
@@ -856,13 +858,14 @@ static void __meminit free_pmd_table(pmd_t *pmd_start, pud_t *pud)
 	}
 
 	/* free a pmd talbe */
-	free_pagetable(pud_page(*pud), 0);
+	free_pagetable(pud_page(*pud), 0, altmap);
 	spin_lock(&init_mm.page_table_lock);
 	pud_clear(pud);
 	spin_unlock(&init_mm.page_table_lock);
 }
 
-static void __meminit free_pud_table(pud_t *pud_start, p4d_t *p4d)
+static void __meminit free_pud_table(pud_t *pud_start, p4d_t *p4d,
+		struct vmem_altmap *altmap)
 {
 	pud_t *pud;
 	int i;
@@ -874,7 +877,7 @@ static void __meminit free_pud_table(pud_t *pud_start, p4d_t *p4d)
 	}
 
 	/* free a pud talbe */
-	free_pagetable(p4d_page(*p4d), 0);
+	free_pagetable(p4d_page(*p4d), 0, altmap);
 	spin_lock(&init_mm.page_table_lock);
 	p4d_clear(p4d);
 	spin_unlock(&init_mm.page_table_lock);
@@ -882,7 +885,7 @@ static void __meminit free_pud_table(pud_t *pud_start, p4d_t *p4d)
 
 static void __meminit
 remove_pte_table(pte_t *pte_start, unsigned long addr, unsigned long end,
-		 bool direct)
+		 struct vmem_altmap *altmap, bool direct)
 {
 	unsigned long next, pages = 0;
 	pte_t *pte;
@@ -913,7 +916,7 @@ remove_pte_table(pte_t *pte_start, unsigned long addr, unsigned long end,
 			 * freed when offlining, or simplely not in use.
 			 */
 			if (!direct)
-				free_pagetable(pte_page(*pte), 0);
+				free_pagetable(pte_page(*pte), 0, altmap);
 
 			spin_lock(&init_mm.page_table_lock);
 			pte_clear(&init_mm, addr, pte);
@@ -936,7 +939,7 @@ remove_pte_table(pte_t *pte_start, unsigned long addr, unsigned long end,
 
 			page_addr = page_address(pte_page(*pte));
 			if (!memchr_inv(page_addr, PAGE_INUSE, PAGE_SIZE)) {
-				free_pagetable(pte_page(*pte), 0);
+				free_pagetable(pte_page(*pte), 0, altmap);
 
 				spin_lock(&init_mm.page_table_lock);
 				pte_clear(&init_mm, addr, pte);
@@ -953,7 +956,7 @@ remove_pte_table(pte_t *pte_start, unsigned long addr, unsigned long end,
 
 static void __meminit
 remove_pmd_table(pmd_t *pmd_start, unsigned long addr, unsigned long end,
-		 bool direct)
+		 bool direct, struct vmem_altmap *altmap)
 {
 	unsigned long next, pages = 0;
 	pte_t *pte_base;
@@ -972,7 +975,8 @@ remove_pmd_table(pmd_t *pmd_start, unsigned long addr, unsigned long end,
 			    IS_ALIGNED(next, PMD_SIZE)) {
 				if (!direct)
 					free_pagetable(pmd_page(*pmd),
-						       get_order(PMD_SIZE));
+						       get_order(PMD_SIZE),
+						       altmap);
 
 				spin_lock(&init_mm.page_table_lock);
 				pmd_clear(pmd);
@@ -986,7 +990,8 @@ remove_pmd_table(pmd_t *pmd_start, unsigned long addr, unsigned long end,
 				if (!memchr_inv(page_addr, PAGE_INUSE,
 						PMD_SIZE)) {
 					free_pagetable(pmd_page(*pmd),
-						       get_order(PMD_SIZE));
+						       get_order(PMD_SIZE),
+						       altmap);
 
 					spin_lock(&init_mm.page_table_lock);
 					pmd_clear(pmd);
@@ -998,8 +1003,8 @@ remove_pmd_table(pmd_t *pmd_start, unsigned long addr, unsigned long end,
 		}
 
 		pte_base = (pte_t *)pmd_page_vaddr(*pmd);
-		remove_pte_table(pte_base, addr, next, direct);
-		free_pte_table(pte_base, pmd);
+		remove_pte_table(pte_base, addr, next, altmap, direct);
+		free_pte_table(pte_base, pmd, altmap);
 	}
 
 	/* Call free_pmd_table() in remove_pud_table(). */
@@ -1009,7 +1014,7 @@ remove_pmd_table(pmd_t *pmd_start, unsigned long addr, unsigned long end,
 
 static void __meminit
 remove_pud_table(pud_t *pud_start, unsigned long addr, unsigned long end,
-		 bool direct)
+		 struct vmem_altmap *altmap, bool direct)
 {
 	unsigned long next, pages = 0;
 	pmd_t *pmd_base;
@@ -1028,7 +1033,8 @@ remove_pud_table(pud_t *pud_start, unsigned long addr, unsigned long end,
 			    IS_ALIGNED(next, PUD_SIZE)) {
 				if (!direct)
 					free_pagetable(pud_page(*pud),
-						       get_order(PUD_SIZE));
+						       get_order(PUD_SIZE),
+						       altmap);
 
 				spin_lock(&init_mm.page_table_lock);
 				pud_clear(pud);
@@ -1042,7 +1048,8 @@ remove_pud_table(pud_t *pud_start, unsigned long addr, unsigned long end,
 				if (!memchr_inv(page_addr, PAGE_INUSE,
 						PUD_SIZE)) {
 					free_pagetable(pud_page(*pud),
-						       get_order(PUD_SIZE));
+						       get_order(PUD_SIZE),
+						       altmap);
 
 					spin_lock(&init_mm.page_table_lock);
 					pud_clear(pud);
@@ -1054,8 +1061,8 @@ remove_pud_table(pud_t *pud_start, unsigned long addr, unsigned long end,
 		}
 
 		pmd_base = pmd_offset(pud, 0);
-		remove_pmd_table(pmd_base, addr, next, direct);
-		free_pmd_table(pmd_base, pud);
+		remove_pmd_table(pmd_base, addr, next, direct, altmap);
+		free_pmd_table(pmd_base, pud, altmap);
 	}
 
 	if (direct)
@@ -1064,7 +1071,7 @@ remove_pud_table(pud_t *pud_start, unsigned long addr, unsigned long end,
 
 static void __meminit
 remove_p4d_table(p4d_t *p4d_start, unsigned long addr, unsigned long end,
-		 bool direct)
+		 struct vmem_altmap *altmap, bool direct)
 {
 	unsigned long next, pages = 0;
 	pud_t *pud_base;
@@ -1080,14 +1087,14 @@ remove_p4d_table(p4d_t *p4d_start, unsigned long addr, unsigned long end,
 		BUILD_BUG_ON(p4d_large(*p4d));
 
 		pud_base = pud_offset(p4d, 0);
-		remove_pud_table(pud_base, addr, next, direct);
+		remove_pud_table(pud_base, addr, next, altmap, direct);
 		/*
 		 * For 4-level page tables we do not want to free PUDs, but in the
 		 * 5-level case we should free them. This code will have to change
 		 * to adapt for boot-time switching between 4 and 5 level page tables.
 		 */
 		if (CONFIG_PGTABLE_LEVELS == 5)
-			free_pud_table(pud_base, p4d);
+			free_pud_table(pud_base, p4d, altmap);
 	}
 
 	if (direct)
@@ -1096,7 +1103,8 @@ remove_p4d_table(p4d_t *p4d_start, unsigned long addr, unsigned long end,
 
 /* start and end are both virtual address. */
 static void __meminit
-remove_pagetable(unsigned long start, unsigned long end, bool direct)
+remove_pagetable(unsigned long start, unsigned long end, bool direct,
+		struct vmem_altmap *altmap)
 {
 	unsigned long next;
 	unsigned long addr;
@@ -1111,15 +1119,16 @@ remove_pagetable(unsigned long start, unsigned long end, bool direct)
 			continue;
 
 		p4d = p4d_offset(pgd, 0);
-		remove_p4d_table(p4d, addr, next, direct);
+		remove_p4d_table(p4d, addr, next, altmap, direct);
 	}
 
 	flush_tlb_all();
 }
 
-void __ref vmemmap_free(unsigned long start, unsigned long end)
+void __ref vmemmap_free(unsigned long start, unsigned long end,
+		struct vmem_altmap *altmap)
 {
-	remove_pagetable(start, end, false);
+	remove_pagetable(start, end, false, altmap);
 }
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
@@ -1129,7 +1138,7 @@ kernel_physical_mapping_remove(unsigned long start, unsigned long end)
 	start = (unsigned long)__va(start);
 	end = (unsigned long)__va(end);
 
-	remove_pagetable(start, end, true);
+	remove_pagetable(start, end, true, NULL);
 }
 
 int __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index e71927d0d46b..20dd98ad44a0 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -331,7 +331,7 @@ extern void remove_memory(int nid, u64 start, u64 size);
 extern int sparse_add_one_section(struct pglist_data *pgdat,
 		unsigned long start_pfn, struct vmem_altmap *altmap);
 extern void sparse_remove_one_section(struct zone *zone, struct mem_section *ms,
-		unsigned long map_offset);
+		unsigned long map_offset, struct vmem_altmap *altmap);
 extern struct page *sparse_decode_mem_map(unsigned long coded_mem_map,
 					  unsigned long pnum);
 extern bool allow_online_pfn_range(int nid, unsigned long pfn, unsigned long nr_pages,
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 2f3a7ebecbe2..9d4cd4c1dc6d 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2561,7 +2561,8 @@ int vmemmap_populate(unsigned long start, unsigned long end, int node,
 		struct vmem_altmap *altmap);
 void vmemmap_populate_print_last(void);
 #ifdef CONFIG_MEMORY_HOTPLUG
-void vmemmap_free(unsigned long start, unsigned long end);
+void vmemmap_free(unsigned long start, unsigned long end,
+		struct vmem_altmap *altmap);
 #endif
 void register_page_bootmem_memmap(unsigned long section_nr, struct page *map,
 				  unsigned long nr_pages);
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index eae6bf47caf7..a8dde9734120 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -536,7 +536,7 @@ static void __remove_zone(struct zone *zone, unsigned long start_pfn)
 }
 
 static int __remove_section(struct zone *zone, struct mem_section *ms,
-		unsigned long map_offset)
+		unsigned long map_offset, struct vmem_altmap *altmap)
 {
 	unsigned long start_pfn;
 	int scn_nr;
@@ -553,7 +553,7 @@ static int __remove_section(struct zone *zone, struct mem_section *ms,
 	start_pfn = section_nr_to_pfn((unsigned long)scn_nr);
 	__remove_zone(zone, start_pfn);
 
-	sparse_remove_one_section(zone, ms, map_offset);
+	sparse_remove_one_section(zone, ms, map_offset, altmap);
 	return 0;
 }
 
@@ -607,7 +607,8 @@ int __remove_pages(struct zone *zone, unsigned long phys_start_pfn,
 	for (i = 0; i < sections_to_remove; i++) {
 		unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION;
 
-		ret = __remove_section(zone, __pfn_to_section(pfn), map_offset);
+		ret = __remove_section(zone, __pfn_to_section(pfn), map_offset,
+				altmap);
 		map_offset = 0;
 		if (ret)
 			break;
diff --git a/mm/sparse.c b/mm/sparse.c
index 5f4a0dac7836..06130c13dc99 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -685,12 +685,13 @@ static inline struct page *kmalloc_section_memmap(unsigned long pnum, int nid,
 	/* This will make the necessary allocations eventually. */
 	return sparse_mem_map_populate(pnum, nid, altmap);
 }
-static void __kfree_section_memmap(struct page *memmap)
+static void __kfree_section_memmap(struct page *memmap,
+		struct vmem_altmap *altmap)
 {
 	unsigned long start = (unsigned long)memmap;
 	unsigned long end = (unsigned long)(memmap + PAGES_PER_SECTION);
 
-	vmemmap_free(start, end);
+	vmemmap_free(start, end, altmap);
 }
 #ifdef CONFIG_MEMORY_HOTREMOVE
 static void free_map_bootmem(struct page *memmap)
@@ -698,7 +699,7 @@ static void free_map_bootmem(struct page *memmap)
 	unsigned long start = (unsigned long)memmap;
 	unsigned long end = (unsigned long)(memmap + PAGES_PER_SECTION);
 
-	vmemmap_free(start, end);
+	vmemmap_free(start, end, NULL);
 }
 #endif /* CONFIG_MEMORY_HOTREMOVE */
 #else
@@ -729,7 +730,8 @@ static inline struct page *kmalloc_section_memmap(unsigned long pnum, int nid,
 	return __kmalloc_section_memmap();
 }
 
-static void __kfree_section_memmap(struct page *memmap)
+static void __kfree_section_memmap(struct page *memmap,
+		struct vmem_altmap *altmap)
 {
 	if (is_vmalloc_addr(memmap))
 		vfree(memmap);
@@ -798,7 +800,7 @@ int __meminit sparse_add_one_section(struct pglist_data *pgdat,
 		return -ENOMEM;
 	usemap = __kmalloc_section_usemap();
 	if (!usemap) {
-		__kfree_section_memmap(memmap);
+		__kfree_section_memmap(memmap, altmap);
 		return -ENOMEM;
 	}
 
@@ -820,7 +822,7 @@ out:
 	pgdat_resize_unlock(pgdat, &flags);
 	if (ret <= 0) {
 		kfree(usemap);
-		__kfree_section_memmap(memmap);
+		__kfree_section_memmap(memmap, altmap);
 	}
 	return ret;
 }
@@ -847,7 +849,8 @@ static inline void clear_hwpoisoned_pages(struct page *memmap, int nr_pages)
 }
 #endif
 
-static void free_section_usemap(struct page *memmap, unsigned long *usemap)
+static void free_section_usemap(struct page *memmap, unsigned long *usemap,
+		struct vmem_altmap *altmap)
 {
 	struct page *usemap_page;
 
@@ -861,7 +864,7 @@ static void free_section_usemap(struct page *memmap, unsigned long *usemap)
 	if (PageSlab(usemap_page) || PageCompound(usemap_page)) {
 		kfree(usemap);
 		if (memmap)
-			__kfree_section_memmap(memmap);
+			__kfree_section_memmap(memmap, altmap);
 		return;
 	}
 
@@ -875,7 +878,7 @@ static void free_section_usemap(struct page *memmap, unsigned long *usemap)
 }
 
 void sparse_remove_one_section(struct zone *zone, struct mem_section *ms,
-		unsigned long map_offset)
+		unsigned long map_offset, struct vmem_altmap *altmap)
 {
 	struct page *memmap = NULL;
 	unsigned long *usemap = NULL, flags;
@@ -893,7 +896,7 @@ void sparse_remove_one_section(struct zone *zone, struct mem_section *ms,
 
 	clear_hwpoisoned_pages(memmap + map_offset,
 			PAGES_PER_SECTION - map_offset);
-	free_section_usemap(memmap, usemap);
+	free_section_usemap(memmap, usemap, altmap);
 }
 #endif /* CONFIG_MEMORY_HOTREMOVE */
 #endif /* CONFIG_MEMORY_HOTPLUG */
-- 
cgit v1.2.3


From a99583e780c751003ac9c0105eec9a3b23ec3bc4 Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Fri, 29 Dec 2017 08:53:57 +0100
Subject: mm: pass the vmem_altmap to memmap_init_zone

Pass the vmem_altmap two levels down instead of needing a lookup.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 arch/ia64/mm/init.c            | 9 +++++----
 include/linux/memory_hotplug.h | 2 +-
 include/linux/mm.h             | 4 ++--
 kernel/memremap.c              | 2 +-
 mm/hmm.c                       | 2 +-
 mm/memory_hotplug.c            | 9 +++++----
 mm/page_alloc.c                | 6 +++---
 7 files changed, 18 insertions(+), 16 deletions(-)

(limited to 'mm')

diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c
index 6a8ce9e1536e..18278b448530 100644
--- a/arch/ia64/mm/init.c
+++ b/arch/ia64/mm/init.c
@@ -501,7 +501,7 @@ virtual_memmap_init(u64 start, u64 end, void *arg)
 	if (map_start < map_end)
 		memmap_init_zone((unsigned long)(map_end - map_start),
 				 args->nid, args->zone, page_to_pfn(map_start),
-				 MEMMAP_EARLY);
+				 MEMMAP_EARLY, NULL);
 	return 0;
 }
 
@@ -509,9 +509,10 @@ void __meminit
 memmap_init (unsigned long size, int nid, unsigned long zone,
 	     unsigned long start_pfn)
 {
-	if (!vmem_map)
-		memmap_init_zone(size, nid, zone, start_pfn, MEMMAP_EARLY);
-	else {
+	if (!vmem_map) {
+		memmap_init_zone(size, nid, zone, start_pfn, MEMMAP_EARLY,
+				NULL);
+	} else {
 		struct page *start;
 		struct memmap_init_callback_data args;
 
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index 20dd98ad44a0..aba5f86eb038 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -324,7 +324,7 @@ extern int add_memory_resource(int nid, struct resource *resource, bool online);
 extern int arch_add_memory(int nid, u64 start, u64 size,
 		struct vmem_altmap *altmap, bool want_memblock);
 extern void move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn,
-		unsigned long nr_pages);
+		unsigned long nr_pages, struct vmem_altmap *altmap);
 extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages);
 extern bool is_memblock_offlined(struct memory_block *mem);
 extern void remove_memory(int nid, u64 start, u64 size);
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 9d4cd4c1dc6d..fd01135324b6 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2069,8 +2069,8 @@ static inline void zero_resv_unavail(void) {}
 #endif
 
 extern void set_dma_reserve(unsigned long new_dma_reserve);
-extern void memmap_init_zone(unsigned long, int, unsigned long,
-				unsigned long, enum memmap_context);
+extern void memmap_init_zone(unsigned long, int, unsigned long, unsigned long,
+		enum memmap_context, struct vmem_altmap *);
 extern void setup_per_zone_wmarks(void);
 extern int __meminit init_per_zone_wmark_min(void);
 extern void mem_init(void);
diff --git a/kernel/memremap.c b/kernel/memremap.c
index 380fca1c4a02..64b12c806cc5 100644
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -432,7 +432,7 @@ void *devm_memremap_pages(struct device *dev, struct resource *res,
 	if (!error)
 		move_pfn_range_to_zone(&NODE_DATA(nid)->node_zones[ZONE_DEVICE],
 					align_start >> PAGE_SHIFT,
-					align_size >> PAGE_SHIFT);
+					align_size >> PAGE_SHIFT, altmap);
 	mem_hotplug_done();
 	if (error)
 		goto err_add_memory;
diff --git a/mm/hmm.c b/mm/hmm.c
index 5d17ba89062f..2f2e13c61040 100644
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -942,7 +942,7 @@ static int hmm_devmem_pages_create(struct hmm_devmem *devmem)
 	}
 	move_pfn_range_to_zone(&NODE_DATA(nid)->node_zones[ZONE_DEVICE],
 				align_start >> PAGE_SHIFT,
-				align_size >> PAGE_SHIFT);
+				align_size >> PAGE_SHIFT, NULL);
 	mem_hotplug_done();
 
 	for (pfn = devmem->pfn_first; pfn < devmem->pfn_last; pfn++) {
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index a8dde9734120..12df8a5fadcc 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -798,8 +798,8 @@ static void __meminit resize_pgdat_range(struct pglist_data *pgdat, unsigned lon
 	pgdat->node_spanned_pages = max(start_pfn + nr_pages, old_end_pfn) - pgdat->node_start_pfn;
 }
 
-void __ref move_pfn_range_to_zone(struct zone *zone,
-		unsigned long start_pfn, unsigned long nr_pages)
+void __ref move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn,
+		unsigned long nr_pages, struct vmem_altmap *altmap)
 {
 	struct pglist_data *pgdat = zone->zone_pgdat;
 	int nid = pgdat->node_id;
@@ -824,7 +824,8 @@ void __ref move_pfn_range_to_zone(struct zone *zone,
 	 * expects the zone spans the pfn range. All the pages in the range
 	 * are reserved so nobody should be touching them so we should be safe
 	 */
-	memmap_init_zone(nr_pages, nid, zone_idx(zone), start_pfn, MEMMAP_HOTPLUG);
+	memmap_init_zone(nr_pages, nid, zone_idx(zone), start_pfn,
+			MEMMAP_HOTPLUG, altmap);
 
 	set_zone_contiguous(zone);
 }
@@ -896,7 +897,7 @@ static struct zone * __meminit move_pfn_range(int online_type, int nid,
 	struct zone *zone;
 
 	zone = zone_for_pfn_range(online_type, nid, start_pfn, nr_pages);
-	move_pfn_range_to_zone(zone, start_pfn, nr_pages);
+	move_pfn_range_to_zone(zone, start_pfn, nr_pages, NULL);
 	return zone;
 }
 
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 7e5e775e97f4..1748dd4a4b1b 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5314,9 +5314,9 @@ void __ref build_all_zonelists(pg_data_t *pgdat)
  * done. Non-atomic initialization, single-pass.
  */
 void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
-		unsigned long start_pfn, enum memmap_context context)
+		unsigned long start_pfn, enum memmap_context context,
+		struct vmem_altmap *altmap)
 {
-	struct vmem_altmap *altmap = to_vmem_altmap(__pfn_to_phys(start_pfn));
 	unsigned long end_pfn = start_pfn + size;
 	pg_data_t *pgdat = NODE_DATA(nid);
 	unsigned long pfn;
@@ -5417,7 +5417,7 @@ static void __meminit zone_init_free_lists(struct zone *zone)
 
 #ifndef __HAVE_ARCH_MEMMAP_INIT
 #define memmap_init(size, nid, zone, start_pfn) \
-	memmap_init_zone((size), (nid), (zone), (start_pfn), MEMMAP_EARLY)
+	memmap_init_zone((size), (nid), (zone), (start_pfn), MEMMAP_EARLY, NULL)
 #endif
 
 static int zone_batchsize(struct zone *zone)
-- 
cgit v1.2.3


From a8fc357b2875da8732c91eb085862a0648d82767 Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Fri, 29 Dec 2017 08:53:58 +0100
Subject: mm: split altmap memory map allocation from normal case

No functional changes, just untangling the call chain and document
why the altmap is passed around the hotplug code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 arch/powerpc/mm/init_64.c |  5 ++++-
 arch/x86/mm/init_64.c     |  5 ++++-
 include/linux/mm.h        |  9 ++-------
 mm/sparse-vmemmap.c       | 15 +++------------
 4 files changed, 13 insertions(+), 21 deletions(-)

(limited to 'mm')

diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c
index db7d4e092157..7a2251d99ed3 100644
--- a/arch/powerpc/mm/init_64.c
+++ b/arch/powerpc/mm/init_64.c
@@ -200,7 +200,10 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
 		if (vmemmap_populated(start, page_size))
 			continue;
 
-		p =  __vmemmap_alloc_block_buf(page_size, node, altmap);
+		if (altmap)
+			p = altmap_alloc_block_buf(page_size, altmap);
+		else
+			p = vmemmap_alloc_block_buf(page_size, node);
 		if (!p)
 			return -ENOMEM;
 
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 0cab4b5b59ba..1ab42c852069 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -1385,7 +1385,10 @@ static int __meminit vmemmap_populate_hugepages(unsigned long start,
 		if (pmd_none(*pmd)) {
 			void *p;
 
-			p = __vmemmap_alloc_block_buf(PMD_SIZE, node, altmap);
+			if (altmap)
+				p = altmap_alloc_block_buf(PMD_SIZE, altmap);
+			else
+				p = vmemmap_alloc_block_buf(PMD_SIZE, node);
 			if (p) {
 				pte_t entry;
 
diff --git a/include/linux/mm.h b/include/linux/mm.h
index fd01135324b6..09637c353de0 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2547,13 +2547,8 @@ pmd_t *vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node);
 pte_t *vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node);
 void *vmemmap_alloc_block(unsigned long size, int node);
 struct vmem_altmap;
-void *__vmemmap_alloc_block_buf(unsigned long size, int node,
-		struct vmem_altmap *altmap);
-static inline void *vmemmap_alloc_block_buf(unsigned long size, int node)
-{
-	return __vmemmap_alloc_block_buf(size, node, NULL);
-}
-
+void *vmemmap_alloc_block_buf(unsigned long size, int node);
+void *altmap_alloc_block_buf(unsigned long size, struct vmem_altmap *altmap);
 void vmemmap_verify(pte_t *, int, unsigned long, unsigned long);
 int vmemmap_populate_basepages(unsigned long start, unsigned long end,
 			       int node);
diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c
index 376dcf05a39c..d012c9e2811b 100644
--- a/mm/sparse-vmemmap.c
+++ b/mm/sparse-vmemmap.c
@@ -74,7 +74,7 @@ void * __meminit vmemmap_alloc_block(unsigned long size, int node)
 }
 
 /* need to make sure size is all the same during early stage */
-static void * __meminit alloc_block_buf(unsigned long size, int node)
+void * __meminit vmemmap_alloc_block_buf(unsigned long size, int node)
 {
 	void *ptr;
 
@@ -129,7 +129,7 @@ static unsigned long __meminit vmem_altmap_alloc(struct vmem_altmap *altmap,
 	return pfn + nr_align;
 }
 
-static void * __meminit altmap_alloc_block_buf(unsigned long size,
+void * __meminit altmap_alloc_block_buf(unsigned long size,
 		struct vmem_altmap *altmap)
 {
 	unsigned long pfn, nr_pfns;
@@ -153,15 +153,6 @@ static void * __meminit altmap_alloc_block_buf(unsigned long size,
 	return ptr;
 }
 
-/* need to make sure size is all the same during early stage */
-void * __meminit __vmemmap_alloc_block_buf(unsigned long size, int node,
-		struct vmem_altmap *altmap)
-{
-	if (altmap)
-		return altmap_alloc_block_buf(size, altmap);
-	return alloc_block_buf(size, node);
-}
-
 void __meminit vmemmap_verify(pte_t *pte, int node,
 				unsigned long start, unsigned long end)
 {
@@ -178,7 +169,7 @@ pte_t * __meminit vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node)
 	pte_t *pte = pte_offset_kernel(pmd, addr);
 	if (pte_none(*pte)) {
 		pte_t entry;
-		void *p = alloc_block_buf(PAGE_SIZE, node);
+		void *p = vmemmap_alloc_block_buf(PAGE_SIZE, node);
 		if (!p)
 			return NULL;
 		entry = pfn_pte(__pa(p) >> PAGE_SHIFT, PAGE_KERNEL);
-- 
cgit v1.2.3


From eb8045335c70ef8b272d2888a225b81344423139 Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Fri, 29 Dec 2017 08:53:59 +0100
Subject: mm: merge vmem_altmap_alloc into altmap_alloc_block_buf

There is no clear separation between the two, so merge them.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 mm/sparse-vmemmap.c | 45 ++++++++++++++++-----------------------------
 1 file changed, 16 insertions(+), 29 deletions(-)

(limited to 'mm')

diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c
index d012c9e2811b..bd0276d5f66b 100644
--- a/mm/sparse-vmemmap.c
+++ b/mm/sparse-vmemmap.c
@@ -107,33 +107,16 @@ static unsigned long __meminit vmem_altmap_nr_free(struct vmem_altmap *altmap)
 }
 
 /**
- * vmem_altmap_alloc - allocate pages from the vmem_altmap reservation
- * @altmap - reserved page pool for the allocation
- * @nr_pfns - size (in pages) of the allocation
+ * altmap_alloc_block_buf - allocate pages from the device page map
+ * @altmap:	device page map
+ * @size:	size (in bytes) of the allocation
  *
- * Allocations are aligned to the size of the request
+ * Allocations are aligned to the size of the request.
  */
-static unsigned long __meminit vmem_altmap_alloc(struct vmem_altmap *altmap,
-		unsigned long nr_pfns)
-{
-	unsigned long pfn = vmem_altmap_next_pfn(altmap);
-	unsigned long nr_align;
-
-	nr_align = 1UL << find_first_bit(&nr_pfns, BITS_PER_LONG);
-	nr_align = ALIGN(pfn, nr_align) - pfn;
-
-	if (nr_pfns + nr_align > vmem_altmap_nr_free(altmap))
-		return ULONG_MAX;
-	altmap->alloc += nr_pfns;
-	altmap->align += nr_align;
-	return pfn + nr_align;
-}
-
 void * __meminit altmap_alloc_block_buf(unsigned long size,
 		struct vmem_altmap *altmap)
 {
-	unsigned long pfn, nr_pfns;
-	void *ptr;
+	unsigned long pfn, nr_pfns, nr_align;
 
 	if (size & ~PAGE_MASK) {
 		pr_warn_once("%s: allocations must be multiple of PAGE_SIZE (%ld)\n",
@@ -141,16 +124,20 @@ void * __meminit altmap_alloc_block_buf(unsigned long size,
 		return NULL;
 	}
 
+	pfn = vmem_altmap_next_pfn(altmap);
 	nr_pfns = size >> PAGE_SHIFT;
-	pfn = vmem_altmap_alloc(altmap, nr_pfns);
-	if (pfn < ULONG_MAX)
-		ptr = __va(__pfn_to_phys(pfn));
-	else
-		ptr = NULL;
+	nr_align = 1UL << find_first_bit(&nr_pfns, BITS_PER_LONG);
+	nr_align = ALIGN(pfn, nr_align) - pfn;
+	if (nr_pfns + nr_align > vmem_altmap_nr_free(altmap))
+		return NULL;
+
+	altmap->alloc += nr_pfns;
+	altmap->align += nr_align;
+	pfn += nr_align;
+
 	pr_debug("%s: pfn: %#lx alloc: %ld align: %ld nr: %#lx\n",
 			__func__, pfn, altmap->alloc, altmap->align, nr_pfns);
-
-	return ptr;
+	return __va(__pfn_to_phys(pfn));
 }
 
 void __meminit vmemmap_verify(pte_t *pte, int node,
-- 
cgit v1.2.3


From 832d7aa051106c927cae05ced29d3fd31459ed21 Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Fri, 29 Dec 2017 08:54:01 +0100
Subject: mm: optimize dev_pagemap reference counting around get_dev_pagemap

Change the calling convention so that get_dev_pagemap always consumes the
previous reference instead of doing this using an explicit earlier call to
put_dev_pagemap in the callers.

The callers will still need to put the final reference after finishing the
loop over the pages.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 kernel/memremap.c | 17 +++++++++--------
 mm/gup.c          |  7 +++++--
 2 files changed, 14 insertions(+), 10 deletions(-)

(limited to 'mm')

diff --git a/kernel/memremap.c b/kernel/memremap.c
index 3df6cd4ffb40..891c77487a6a 100644
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -507,22 +507,23 @@ struct vmem_altmap *to_vmem_altmap(unsigned long memmap_start)
  * @pfn: page frame number to lookup page_map
  * @pgmap: optional known pgmap that already has a reference
  *
- * @pgmap allows the overhead of a lookup to be bypassed when @pfn lands in the
- * same mapping.
+ * If @pgmap is non-NULL and covers @pfn it will be returned as-is.  If @pgmap
+ * is non-NULL but does not cover @pfn the reference to it will be released.
  */
 struct dev_pagemap *get_dev_pagemap(unsigned long pfn,
 		struct dev_pagemap *pgmap)
 {
-	const struct resource *res = pgmap ? pgmap->res : NULL;
 	resource_size_t phys = PFN_PHYS(pfn);
 
 	/*
-	 * In the cached case we're already holding a live reference so
-	 * we can simply do a blind increment
+	 * In the cached case we're already holding a live reference.
 	 */
-	if (res && phys >= res->start && phys <= res->end) {
-		percpu_ref_get(pgmap->ref);
-		return pgmap;
+	if (pgmap) {
+		const struct resource *res = pgmap ? pgmap->res : NULL;
+
+		if (res && phys >= res->start && phys <= res->end)
+			return pgmap;
+		put_dev_pagemap(pgmap);
 	}
 
 	/* fall back to slow path lookup */
diff --git a/mm/gup.c b/mm/gup.c
index e0d82b6706d7..3affe7544b0c 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -1410,7 +1410,6 @@ static int gup_pte_range(pmd_t pmd, unsigned long addr, unsigned long end,
 
 		VM_BUG_ON_PAGE(compound_head(page) != head, page);
 
-		put_dev_pagemap(pgmap);
 		SetPageReferenced(page);
 		pages[*nr] = page;
 		(*nr)++;
@@ -1420,6 +1419,8 @@ static int gup_pte_range(pmd_t pmd, unsigned long addr, unsigned long end,
 	ret = 1;
 
 pte_unmap:
+	if (pgmap)
+		put_dev_pagemap(pgmap);
 	pte_unmap(ptem);
 	return ret;
 }
@@ -1459,10 +1460,12 @@ static int __gup_device_huge(unsigned long pfn, unsigned long addr,
 		SetPageReferenced(page);
 		pages[*nr] = page;
 		get_page(page);
-		put_dev_pagemap(pgmap);
 		(*nr)++;
 		pfn++;
 	} while (addr += PAGE_SIZE, addr != end);
+
+	if (pgmap)
+		put_dev_pagemap(pgmap);
 	return 1;
 }
 
-- 
cgit v1.2.3


From e7744aa25cffe26d3767c9ffcf4e130cca1dff00 Mon Sep 17 00:00:00 2001
From: Logan Gunthorpe <logang@deltatee.com>
Date: Fri, 29 Dec 2017 08:54:04 +0100
Subject: memremap: drop private struct page_map

'struct page_map' is a private structure of 'struct dev_pagemap' but the
latter replicates all the same fields as the former so there isn't much
value in it. Thus drop it in favour of a completely public struct.

This is a clean up in preperation for a more generally useful
'devm_memeremap_pages' interface.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 include/linux/memremap.h |  5 ++--
 kernel/memremap.c        | 68 ++++++++++++++++++------------------------------
 mm/hmm.c                 |  2 +-
 3 files changed, 30 insertions(+), 45 deletions(-)

(limited to 'mm')

diff --git a/include/linux/memremap.h b/include/linux/memremap.h
index 3fddcfe57bb0..1cb5f39d25c1 100644
--- a/include/linux/memremap.h
+++ b/include/linux/memremap.h
@@ -113,8 +113,9 @@ typedef void (*dev_page_free_t)(struct page *page, void *data);
 struct dev_pagemap {
 	dev_page_fault_t page_fault;
 	dev_page_free_t page_free;
-	struct vmem_altmap *altmap;
-	const struct resource *res;
+	struct vmem_altmap altmap;
+	bool altmap_valid;
+	struct resource res;
 	struct percpu_ref *ref;
 	struct device *dev;
 	void *data;
diff --git a/kernel/memremap.c b/kernel/memremap.c
index 12e78528fea4..9207c44cce20 100644
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -188,13 +188,6 @@ static RADIX_TREE(pgmap_radix, GFP_KERNEL);
 #define SECTION_MASK ~((1UL << PA_SECTION_SHIFT) - 1)
 #define SECTION_SIZE (1UL << PA_SECTION_SHIFT)
 
-struct page_map {
-	struct resource res;
-	struct percpu_ref *ref;
-	struct dev_pagemap pgmap;
-	struct vmem_altmap altmap;
-};
-
 static unsigned long order_at(struct resource *res, unsigned long pgoff)
 {
 	unsigned long phys_pgoff = PHYS_PFN(res->start) + pgoff;
@@ -260,22 +253,21 @@ static void pgmap_radix_release(struct resource *res)
 	synchronize_rcu();
 }
 
-static unsigned long pfn_first(struct page_map *page_map)
+static unsigned long pfn_first(struct dev_pagemap *pgmap)
 {
-	struct dev_pagemap *pgmap = &page_map->pgmap;
-	const struct resource *res = &page_map->res;
-	struct vmem_altmap *altmap = pgmap->altmap;
+	const struct resource *res = &pgmap->res;
+	struct vmem_altmap *altmap = &pgmap->altmap;
 	unsigned long pfn;
 
 	pfn = res->start >> PAGE_SHIFT;
-	if (altmap)
+	if (pgmap->altmap_valid)
 		pfn += vmem_altmap_offset(altmap);
 	return pfn;
 }
 
-static unsigned long pfn_end(struct page_map *page_map)
+static unsigned long pfn_end(struct dev_pagemap *pgmap)
 {
-	const struct resource *res = &page_map->res;
+	const struct resource *res = &pgmap->res;
 
 	return (res->start + resource_size(res)) >> PAGE_SHIFT;
 }
@@ -285,13 +277,12 @@ static unsigned long pfn_end(struct page_map *page_map)
 
 static void devm_memremap_pages_release(struct device *dev, void *data)
 {
-	struct page_map *page_map = data;
-	struct resource *res = &page_map->res;
+	struct dev_pagemap *pgmap = data;
+	struct resource *res = &pgmap->res;
 	resource_size_t align_start, align_size;
-	struct dev_pagemap *pgmap = &page_map->pgmap;
 	unsigned long pfn;
 
-	for_each_device_pfn(pfn, page_map)
+	for_each_device_pfn(pfn, pgmap)
 		put_page(pfn_to_page(pfn));
 
 	if (percpu_ref_tryget_live(pgmap->ref)) {
@@ -304,24 +295,22 @@ static void devm_memremap_pages_release(struct device *dev, void *data)
 	align_size = ALIGN(resource_size(res), SECTION_SIZE);
 
 	mem_hotplug_begin();
-	arch_remove_memory(align_start, align_size, pgmap->altmap);
+	arch_remove_memory(align_start, align_size, pgmap->altmap_valid ?
+			&pgmap->altmap : NULL);
 	mem_hotplug_done();
 
 	untrack_pfn(NULL, PHYS_PFN(align_start), align_size);
 	pgmap_radix_release(res);
-	dev_WARN_ONCE(dev, pgmap->altmap && pgmap->altmap->alloc,
-			"%s: failed to free all reserved pages\n", __func__);
+	dev_WARN_ONCE(dev, pgmap->altmap.alloc,
+		      "%s: failed to free all reserved pages\n", __func__);
 }
 
 /* assumes rcu_read_lock() held at entry */
 static struct dev_pagemap *find_dev_pagemap(resource_size_t phys)
 {
-	struct page_map *page_map;
-
 	WARN_ON_ONCE(!rcu_read_lock_held());
 
-	page_map = radix_tree_lookup(&pgmap_radix, PHYS_PFN(phys));
-	return page_map ? &page_map->pgmap : NULL;
+	return radix_tree_lookup(&pgmap_radix, PHYS_PFN(phys));
 }
 
 /**
@@ -349,7 +338,6 @@ void *devm_memremap_pages(struct device *dev, struct resource *res,
 	unsigned long pfn, pgoff, order;
 	pgprot_t pgprot = PAGE_KERNEL;
 	struct dev_pagemap *pgmap;
-	struct page_map *page_map;
 	int error, nid, is_ram, i = 0;
 
 	align_start = res->start & ~(SECTION_SIZE - 1);
@@ -370,22 +358,20 @@ void *devm_memremap_pages(struct device *dev, struct resource *res,
 	if (!ref)
 		return ERR_PTR(-EINVAL);
 
-	page_map = devres_alloc_node(devm_memremap_pages_release,
-			sizeof(*page_map), GFP_KERNEL, dev_to_node(dev));
-	if (!page_map)
+	pgmap = devres_alloc_node(devm_memremap_pages_release,
+			sizeof(*pgmap), GFP_KERNEL, dev_to_node(dev));
+	if (!pgmap)
 		return ERR_PTR(-ENOMEM);
-	pgmap = &page_map->pgmap;
 
-	memcpy(&page_map->res, res, sizeof(*res));
+	memcpy(&pgmap->res, res, sizeof(*res));
 
 	pgmap->dev = dev;
 	if (altmap) {
-		memcpy(&page_map->altmap, altmap, sizeof(*altmap));
-		pgmap->altmap = &page_map->altmap;
-		altmap = pgmap->altmap;
+		memcpy(&pgmap->altmap, altmap, sizeof(*altmap));
+		pgmap->altmap_valid = true;
+		altmap = &pgmap->altmap;
 	}
 	pgmap->ref = ref;
-	pgmap->res = &page_map->res;
 	pgmap->type = MEMORY_DEVICE_HOST;
 	pgmap->page_fault = NULL;
 	pgmap->page_free = NULL;
@@ -397,7 +383,7 @@ void *devm_memremap_pages(struct device *dev, struct resource *res,
 
 	foreach_order_pgoff(res, order, pgoff) {
 		error = __radix_tree_insert(&pgmap_radix,
-				PHYS_PFN(res->start) + pgoff, order, page_map);
+				PHYS_PFN(res->start) + pgoff, order, pgmap);
 		if (error) {
 			dev_err(dev, "%s: failed: %d\n", __func__, error);
 			break;
@@ -426,7 +412,7 @@ void *devm_memremap_pages(struct device *dev, struct resource *res,
 	if (error)
 		goto err_add_memory;
 
-	for_each_device_pfn(pfn, page_map) {
+	for_each_device_pfn(pfn, pgmap) {
 		struct page *page = pfn_to_page(pfn);
 
 		/*
@@ -441,7 +427,7 @@ void *devm_memremap_pages(struct device *dev, struct resource *res,
 		if (!(++i % 1024))
 			cond_resched();
 	}
-	devres_add(dev, page_map);
+	devres_add(dev, pgmap);
 	return __va(res->start);
 
  err_add_memory:
@@ -449,7 +435,7 @@ void *devm_memremap_pages(struct device *dev, struct resource *res,
  err_pfn_remap:
  err_radix:
 	pgmap_radix_release(res);
-	devres_free(page_map);
+	devres_free(pgmap);
 	return ERR_PTR(error);
 }
 EXPORT_SYMBOL(devm_memremap_pages);
@@ -482,9 +468,7 @@ struct dev_pagemap *get_dev_pagemap(unsigned long pfn,
 	 * In the cached case we're already holding a live reference.
 	 */
 	if (pgmap) {
-		const struct resource *res = pgmap ? pgmap->res : NULL;
-
-		if (res && phys >= res->start && phys <= res->end)
+		if (phys >= pgmap->res.start && phys <= pgmap->res.end)
 			return pgmap;
 		put_dev_pagemap(pgmap);
 	}
diff --git a/mm/hmm.c b/mm/hmm.c
index 2f2e13c61040..320fdc87f064 100644
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -882,7 +882,7 @@ static int hmm_devmem_pages_create(struct hmm_devmem *devmem)
 	else
 		devmem->pagemap.type = MEMORY_DEVICE_PRIVATE;
 
-	devmem->pagemap.res = devmem->resource;
+	devmem->pagemap.res = *devmem->resource;
 	devmem->pagemap.page_fault = hmm_devmem_fault;
 	devmem->pagemap.page_free = hmm_devmem_free;
 	devmem->pagemap.dev = devmem->device;
-- 
cgit v1.2.3


From 785a3fab4adbf91b2189c928a59ae219c54ba95e Mon Sep 17 00:00:00 2001
From: Dan Williams <dan.j.williams@intel.com>
Date: Mon, 23 Oct 2017 07:20:00 -0700
Subject: mm, dax: introduce pfn_t_special()

In support of removing the VM_MIXEDMAP indication from DAX VMAs,
introduce pfn_t_special() for drivers to indicate that _PAGE_SPECIAL
should be used for DAX ptes. This also helps identify drivers like
dccssblk that only want to use DAX in a read-only fashion without
get_user_pages() support.

Ideally we could delete axonram and dcssblk DAX support, but if we need
to keep it better make it explicit that axonram and dcssblk only support
a sub-set of DAX due to missing _PAGE_DEVMAP support.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 arch/powerpc/sysdev/axonram.c |  2 +-
 drivers/s390/block/dcssblk.c  |  3 ++-
 include/linux/pfn_t.h         | 13 +++++++++++++
 mm/memory.c                   | 16 +++++++++++++++-
 4 files changed, 31 insertions(+), 3 deletions(-)

(limited to 'mm')

diff --git a/arch/powerpc/sysdev/axonram.c b/arch/powerpc/sysdev/axonram.c
index 1b307c80b401..cdbb0e59b3d3 100644
--- a/arch/powerpc/sysdev/axonram.c
+++ b/arch/powerpc/sysdev/axonram.c
@@ -151,7 +151,7 @@ __axon_ram_direct_access(struct axon_ram_bank *bank, pgoff_t pgoff, long nr_page
 	resource_size_t offset = pgoff * PAGE_SIZE;
 
 	*kaddr = (void *) bank->io_addr + offset;
-	*pfn = phys_to_pfn_t(bank->ph_addr + offset, PFN_DEV);
+	*pfn = phys_to_pfn_t(bank->ph_addr + offset, PFN_DEV|PFN_SPECIAL);
 	return (bank->size - offset) / PAGE_SIZE;
 }
 
diff --git a/drivers/s390/block/dcssblk.c b/drivers/s390/block/dcssblk.c
index 6aaefb780436..9cae08b36b80 100644
--- a/drivers/s390/block/dcssblk.c
+++ b/drivers/s390/block/dcssblk.c
@@ -916,7 +916,8 @@ __dcssblk_direct_access(struct dcssblk_dev_info *dev_info, pgoff_t pgoff,
 
 	dev_sz = dev_info->end - dev_info->start + 1;
 	*kaddr = (void *) dev_info->start + offset;
-	*pfn = __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset), PFN_DEV);
+	*pfn = __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset),
+			PFN_DEV|PFN_SPECIAL);
 
 	return (dev_sz - offset) / PAGE_SIZE;
 }
diff --git a/include/linux/pfn_t.h b/include/linux/pfn_t.h
index 43b1d7648e82..a03c2642a87c 100644
--- a/include/linux/pfn_t.h
+++ b/include/linux/pfn_t.h
@@ -15,8 +15,10 @@
 #define PFN_SG_LAST (1ULL << (BITS_PER_LONG_LONG - 2))
 #define PFN_DEV (1ULL << (BITS_PER_LONG_LONG - 3))
 #define PFN_MAP (1ULL << (BITS_PER_LONG_LONG - 4))
+#define PFN_SPECIAL (1ULL << (BITS_PER_LONG_LONG - 5))
 
 #define PFN_FLAGS_TRACE \
+	{ PFN_SPECIAL,	"SPECIAL" }, \
 	{ PFN_SG_CHAIN,	"SG_CHAIN" }, \
 	{ PFN_SG_LAST,	"SG_LAST" }, \
 	{ PFN_DEV,	"DEV" }, \
@@ -120,4 +122,15 @@ pud_t pud_mkdevmap(pud_t pud);
 #endif
 #endif /* __HAVE_ARCH_PTE_DEVMAP */
 
+#ifdef __HAVE_ARCH_PTE_SPECIAL
+static inline bool pfn_t_special(pfn_t pfn)
+{
+	return (pfn.val & PFN_SPECIAL) == PFN_SPECIAL;
+}
+#else
+static inline bool pfn_t_special(pfn_t pfn)
+{
+	return false;
+}
+#endif /* __HAVE_ARCH_PTE_SPECIAL */
 #endif /* _LINUX_PFN_T_H_ */
diff --git a/mm/memory.c b/mm/memory.c
index ca5674cbaff2..46b6c33b7f04 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1897,12 +1897,26 @@ int vm_insert_pfn_prot(struct vm_area_struct *vma, unsigned long addr,
 }
 EXPORT_SYMBOL(vm_insert_pfn_prot);
 
+static bool vm_mixed_ok(struct vm_area_struct *vma, pfn_t pfn)
+{
+	/* these checks mirror the abort conditions in vm_normal_page */
+	if (vma->vm_flags & VM_MIXEDMAP)
+		return true;
+	if (pfn_t_devmap(pfn))
+		return true;
+	if (pfn_t_special(pfn))
+		return true;
+	if (is_zero_pfn(pfn_t_to_pfn(pfn)))
+		return true;
+	return false;
+}
+
 static int __vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
 			pfn_t pfn, bool mkwrite)
 {
 	pgprot_t pgprot = vma->vm_page_prot;
 
-	BUG_ON(!(vma->vm_flags & VM_MIXEDMAP));
+	BUG_ON(!vm_mixed_ok(vma, pfn));
 
 	if (addr < vma->vm_start || addr >= vma->vm_end)
 		return -EFAULT;
-- 
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