mm, memory_hotplug: provide a more generic restrictions for memory hotplug

arch_add_memory, __add_pages take a want_memblock which controls whether
the newly added memory should get the sysfs memblock user API (e.g.
ZONE_DEVICE users do not want/need this interface).  Some callers even
want to control where do we allocate the memmap from by configuring
altmap.

Add a more generic hotplug context for arch_add_memory and __add_pages.
struct mhp_restrictions contains flags which contains additional features
to be enabled by the memory hotplug (MHP_MEMBLOCK_API currently) and
altmap for alternative memmap allocator.

This patch shouldn't introduce any functional change.

[akpm@linux-foundation.org: build fix]
Link: http://lkml.kernel.org/r/20190408082633.2864-3-osalvador@suse.de
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index ef82312..ef32d48 100644 (file)
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -1065,8 +1065,8 @@ int p4d_free_pud_page(p4d_t *p4d, unsigned long addr)
 }
 
 #ifdef CONFIG_MEMORY_HOTPLUG
-int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
-                   bool want_memblock)
+int arch_add_memory(int nid, u64 start, u64 size,
+                       struct mhp_restrictions *restrictions)
 {
        int flags = 0;
 
@@ -1077,6 +1077,6 @@ int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
                             size, PAGE_KERNEL, __pgd_pgtable_alloc, flags);
 
        return __add_pages(nid, start >> PAGE_SHIFT, size >> PAGE_SHIFT,
-                          altmap, want_memblock);
+                          restrictions);
 }
 #endif

diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c
index e49200e..379eb1f 100644 (file)
--- a/arch/ia64/mm/init.c
+++ b/arch/ia64/mm/init.c
@@ -666,14 +666,14 @@ mem_init (void)
 }
 
 #ifdef CONFIG_MEMORY_HOTPLUG
-int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
-               bool want_memblock)
+int arch_add_memory(int nid, u64 start, u64 size,
+                       struct mhp_restrictions *restrictions)
 {
        unsigned long start_pfn = start >> PAGE_SHIFT;
        unsigned long nr_pages = size >> PAGE_SHIFT;
        int ret;
 
-       ret = __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock);
+       ret = __add_pages(nid, start_pfn, nr_pages, restrictions);
        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 2026689..de5c591 100644 (file)
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -109,8 +109,8 @@ int __weak remove_section_mapping(unsigned long start, unsigned long end)
        return -ENODEV;
 }
 
-int __ref arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
-                         bool want_memblock)
+int __ref arch_add_memory(int nid, u64 start, u64 size,
+                       struct mhp_restrictions *restrictions)
 {
        unsigned long start_pfn = start >> PAGE_SHIFT;
        unsigned long nr_pages = size >> PAGE_SHIFT;
@@ -127,7 +127,7 @@ int __ref arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altm
        }
        flush_inval_dcache_range(start, start + size);
 
-       return __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock);
+       return __add_pages(nid, start_pfn, nr_pages, restrictions);
 }
 
 #ifdef CONFIG_MEMORY_HOTREMOVE

diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index 5f48fc7..06bd051 100644 (file)
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -219,8 +219,8 @@ device_initcall(s390_cma_mem_init);
 
 #endif /* CONFIG_CMA */
 
-int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
-               bool want_memblock)
+int arch_add_memory(int nid, u64 start, u64 size,
+               struct mhp_restrictions *restrictions)
 {
        unsigned long start_pfn = PFN_DOWN(start);
        unsigned long size_pages = PFN_DOWN(size);
@@ -230,7 +230,7 @@ int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
        if (rc)
                return rc;
 
-       rc = __add_pages(nid, start_pfn, size_pages, altmap, want_memblock);
+       rc = __add_pages(nid, start_pfn, size_pages, restrictions);
        if (rc)
                vmem_remove_mapping(start, size);
        return rc;

diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c
index aeb9f45..d3cd07b 100644 (file)
--- a/arch/sh/mm/init.c
+++ b/arch/sh/mm/init.c
@@ -404,15 +404,15 @@ void __init mem_init(void)
 }
 
 #ifdef CONFIG_MEMORY_HOTPLUG
-int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
-               bool want_memblock)
+int arch_add_memory(int nid, u64 start, u64 size,
+                       struct mhp_restrictions *restrictions)
 {
        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, altmap, want_memblock);
+       ret = __add_pages(nid, start_pfn, nr_pages, restrictions);
        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 85c94f9..755dbed 100644 (file)
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -850,13 +850,13 @@ void __init mem_init(void)
 }
 
 #ifdef CONFIG_MEMORY_HOTPLUG
-int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
-               bool want_memblock)
+int arch_add_memory(int nid, u64 start, u64 size,
+                       struct mhp_restrictions *restrictions)
 {
        unsigned long start_pfn = start >> PAGE_SHIFT;
        unsigned long nr_pages = size >> PAGE_SHIFT;
 
-       return __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock);
+       return __add_pages(nid, start_pfn, nr_pages, restrictions);
 }
 
 #ifdef CONFIG_MEMORY_HOTREMOVE

diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index bccff68..db42c11 100644 (file)
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -777,11 +777,11 @@ static void update_end_of_memory_vars(u64 start, u64 size)
 }
 
 int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
-               struct vmem_altmap *altmap, bool want_memblock)
+                               struct mhp_restrictions *restrictions)
 {
        int ret;
 
-       ret = __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock);
+       ret = __add_pages(nid, start_pfn, nr_pages, restrictions);
        WARN_ON_ONCE(ret);
 
        /* update max_pfn, max_low_pfn and high_memory */
@@ -791,15 +791,15 @@ int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
        return ret;
 }
 
-int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
-               bool want_memblock)
+int arch_add_memory(int nid, u64 start, u64 size,
+                       struct mhp_restrictions *restrictions)
 {
        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, altmap, want_memblock);
+       return add_pages(nid, start_pfn, nr_pages, restrictions);
 }
 
 #define PAGE_INUSE 0xFD

diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index 3c8cf34..b24aca5 100644 (file)
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -54,6 +54,16 @@ enum {
 };
 
 /*
+ * Restrictions for the memory hotplug:
+ * flags:  MHP_ flags
+ * altmap: alternative allocator for memmap array
+ */
+struct mhp_restrictions {
+       unsigned long flags;
+       struct vmem_altmap *altmap;
+};
+
+/*
  * Zone resizing functions
  *
  * Note: any attempt to resize a zone should has pgdat_resize_lock()
@@ -101,6 +111,8 @@ extern void __online_page_free(struct page *page);
 
 extern int try_online_node(int nid);
 
+extern int arch_add_memory(int nid, u64 start, u64 size,
+                       struct mhp_restrictions *restrictions);
 extern u64 max_mem_size;
 
 extern bool memhp_auto_online;
@@ -118,20 +130,27 @@ extern int __remove_pages(struct zone *zone, unsigned long start_pfn,
        unsigned long nr_pages, struct vmem_altmap *altmap);
 #endif /* CONFIG_MEMORY_HOTREMOVE */
 
+/*
+ * Do we want sysfs memblock files created. This will allow userspace to online
+ * and offline memory explicitly. Lack of this bit means that the caller has to
+ * call move_pfn_range_to_zone to finish the initialization.
+ */
+
+#define MHP_MEMBLOCK_API               (1<<0)
+
 /* reasonably generic interface to expand the physical pages */
 extern int __add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
-               struct vmem_altmap *altmap, bool want_memblock);
+                      struct mhp_restrictions *restrictions);
 
 #ifndef CONFIG_ARCH_HAS_ADD_PAGES
 static inline int add_pages(int nid, unsigned long start_pfn,
-               unsigned long nr_pages, struct vmem_altmap *altmap,
-               bool want_memblock)
+               unsigned long nr_pages, struct mhp_restrictions *restrictions)
 {
-       return __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock);
+       return __add_pages(nid, start_pfn, nr_pages, restrictions);
 }
 #else /* ARCH_HAS_ADD_PAGES */
 int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
-               struct vmem_altmap *altmap, bool want_memblock);
+             struct mhp_restrictions *restrictions);
 #endif /* ARCH_HAS_ADD_PAGES */
 
 #ifdef CONFIG_NUMA
@@ -332,8 +351,6 @@ extern int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn,
 extern int __add_memory(int nid, u64 start, u64 size);
 extern int add_memory(int nid, u64 start, u64 size);
 extern int add_memory_resource(int nid, struct resource *resource);
-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, struct vmem_altmap *altmap);
 extern bool is_memblock_offlined(struct memory_block *mem);

diff --git a/kernel/memremap.c b/kernel/memremap.c
index a856cb5..4e59d29 100644 (file)
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -148,6 +148,12 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
                        &pgmap->altmap : NULL;
        struct resource *res = &pgmap->res;
        struct dev_pagemap *conflict_pgmap;
+       struct mhp_restrictions restrictions = {
+               /*
+                * We do not want any optional features only our own memmap
+               */
+               .altmap = altmap,
+       };
        pgprot_t pgprot = PAGE_KERNEL;
        int error, nid, is_ram;
 
@@ -214,7 +220,7 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
         */
        if (pgmap->type == MEMORY_DEVICE_PRIVATE) {
                error = add_pages(nid, align_start >> PAGE_SHIFT,
-                               align_size >> PAGE_SHIFT, NULL, false);
+                               align_size >> PAGE_SHIFT, &restrictions);
        } else {
                error = kasan_add_zero_shadow(__va(align_start), align_size);
                if (error) {
@@ -222,8 +228,8 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
                        goto err_kasan;
                }
 
-               error = arch_add_memory(nid, align_start, align_size, altmap,
-                               false);
+               error = arch_add_memory(nid, align_start, align_size,
+                                       &restrictions);
        }
 
        if (!error) {

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 75f9f65..339d5a6 100644 (file)
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -273,12 +273,12 @@ 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, struct vmem_altmap *altmap,
-               bool want_memblock)
+               unsigned long nr_pages, struct mhp_restrictions *restrictions)
 {
        unsigned long i;
        int err = 0;
        int start_sec, end_sec;
+       struct vmem_altmap *altmap = restrictions->altmap;
 
        /* during initialize mem_map, align hot-added range to section */
        start_sec = pfn_to_section_nr(phys_start_pfn);
@@ -299,7 +299,7 @@ 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), altmap,
-                               want_memblock);
+                               restrictions->flags & MHP_MEMBLOCK_API);
 
                /*
                 * EEXIST is finally dealt with by ioresource collision
@@ -1097,6 +1097,9 @@ static int online_memory_block(struct memory_block *mem, void *arg)
  */
 int __ref add_memory_resource(int nid, struct resource *res)
 {
+       struct mhp_restrictions restrictions = {
+               .flags = MHP_MEMBLOCK_API,
+       };
        u64 start, size;
        bool new_node = false;
        int ret;
@@ -1124,7 +1127,7 @@ int __ref add_memory_resource(int nid, struct resource *res)
        new_node = ret;
 
        /* call arch's memory hotadd */
-       ret = arch_add_memory(nid, start, size, NULL, true);
+       ret = arch_add_memory(nid, start, size, &restrictions);
        if (ret < 0)
                goto error;