diff --git a/drivers/base/memory.c b/drivers/base/memory.c index b456ac213610..8191709c9ad2 100644 --- a/drivers/base/memory.c +++ b/drivers/base/memory.c @@ -105,7 +105,8 @@ EXPORT_SYMBOL(unregister_memory_notifier); static void memory_block_release(struct device *dev) { struct memory_block *mem = to_memory_block(dev); - + /* Verify that the altmap is freed */ + WARN_ON(mem->altmap); kfree(mem); } @@ -183,7 +184,7 @@ static int memory_block_online(struct memory_block *mem) { unsigned long start_pfn = section_nr_to_pfn(mem->start_section_nr); unsigned long nr_pages = PAGES_PER_SECTION * sections_per_block; - unsigned long nr_vmemmap_pages = mem->nr_vmemmap_pages; + unsigned long nr_vmemmap_pages = 0; struct zone *zone; int ret; @@ -200,6 +201,9 @@ static int memory_block_online(struct memory_block *mem) * stage helps to keep accounting easier to follow - e.g vmemmaps * belong to the same zone as the memory they backed. */ + if (mem->altmap) + nr_vmemmap_pages = mem->altmap->free; + if (nr_vmemmap_pages) { ret = mhp_init_memmap_on_memory(start_pfn, nr_vmemmap_pages, zone); if (ret) @@ -230,7 +234,7 @@ static int memory_block_offline(struct memory_block *mem) { unsigned long start_pfn = section_nr_to_pfn(mem->start_section_nr); unsigned long nr_pages = PAGES_PER_SECTION * sections_per_block; - unsigned long nr_vmemmap_pages = mem->nr_vmemmap_pages; + unsigned long nr_vmemmap_pages = 0; int ret; if (!mem->zone) @@ -240,6 +244,9 @@ static int memory_block_offline(struct memory_block *mem) * Unaccount before offlining, such that unpopulated zone and kthreads * can properly be torn down in offline_pages(). */ + if (mem->altmap) + nr_vmemmap_pages = mem->altmap->free; + if (nr_vmemmap_pages) adjust_present_page_count(pfn_to_page(start_pfn), mem->group, -nr_vmemmap_pages); @@ -726,7 +733,7 @@ void memory_block_add_nid(struct memory_block *mem, int nid, #endif static int add_memory_block(unsigned long block_id, unsigned long state, - unsigned long nr_vmemmap_pages, + struct vmem_altmap *altmap, struct memory_group *group) { struct memory_block *mem; @@ -744,7 +751,7 @@ static int add_memory_block(unsigned long block_id, unsigned long state, mem->start_section_nr = block_id * sections_per_block; mem->state = state; mem->nid = NUMA_NO_NODE; - mem->nr_vmemmap_pages = nr_vmemmap_pages; + mem->altmap = altmap; INIT_LIST_HEAD(&mem->group_next); #ifndef CONFIG_NUMA @@ -783,14 +790,14 @@ static int __init add_boot_memory_block(unsigned long base_section_nr) if (section_count == 0) return 0; return add_memory_block(memory_block_id(base_section_nr), - MEM_ONLINE, 0, NULL); + MEM_ONLINE, NULL, NULL); } static int add_hotplug_memory_block(unsigned long block_id, - unsigned long nr_vmemmap_pages, + struct vmem_altmap *altmap, struct memory_group *group) { - return add_memory_block(block_id, MEM_OFFLINE, nr_vmemmap_pages, group); + return add_memory_block(block_id, MEM_OFFLINE, altmap, group); } static void remove_memory_block(struct memory_block *memory) @@ -818,7 +825,7 @@ static void remove_memory_block(struct memory_block *memory) * Called under device_hotplug_lock. */ int create_memory_block_devices(unsigned long start, unsigned long size, - unsigned long vmemmap_pages, + struct vmem_altmap *altmap, struct memory_group *group) { const unsigned long start_block_id = pfn_to_block_id(PFN_DOWN(start)); @@ -832,7 +839,7 @@ int create_memory_block_devices(unsigned long start, unsigned long size, return -EINVAL; for (block_id = start_block_id; block_id != end_block_id; block_id++) { - ret = add_hotplug_memory_block(block_id, vmemmap_pages, group); + ret = add_hotplug_memory_block(block_id, altmap, group); if (ret) break; } diff --git a/include/linux/memory.h b/include/linux/memory.h index 31343566c221..f53cfdaaaa41 100644 --- a/include/linux/memory.h +++ b/include/linux/memory.h @@ -77,11 +77,7 @@ struct memory_block { */ struct zone *zone; struct device dev; - /* - * Number of vmemmap pages. These pages - * lay at the beginning of the memory block. - */ - unsigned long nr_vmemmap_pages; + struct vmem_altmap *altmap; struct memory_group *group; /* group (if any) for this block */ struct list_head group_next; /* next block inside memory group */ #if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_MEMORY_HOTPLUG) @@ -147,7 +143,7 @@ static inline int hotplug_memory_notifier(notifier_fn_t fn, int pri) extern int register_memory_notifier(struct notifier_block *nb); extern void unregister_memory_notifier(struct notifier_block *nb); int create_memory_block_devices(unsigned long start, unsigned long size, - unsigned long vmemmap_pages, + struct vmem_altmap *altmap, struct memory_group *group); void remove_memory_block_devices(unsigned long start, unsigned long size); extern void memory_dev_init(void); diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 76b813991bdc..1b03f4ec6fd2 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1439,7 +1439,13 @@ int __ref add_memory_resource(int nid, struct resource *res, mhp_t mhp_flags) if (mhp_flags & MHP_MEMMAP_ON_MEMORY) { if (mhp_supports_memmap_on_memory(size)) { mhp_altmap.free = memory_block_memmap_on_memory_pages(); - params.altmap = &mhp_altmap; + params.altmap = kmalloc(sizeof(struct vmem_altmap), GFP_KERNEL); + if (!params.altmap) { + ret = -ENOMEM; + goto error; + } + + memcpy(params.altmap, &mhp_altmap, sizeof(mhp_altmap)); } /* fallback to not using altmap */ } @@ -1447,13 +1453,13 @@ int __ref add_memory_resource(int nid, struct resource *res, mhp_t mhp_flags) /* call arch's memory hotadd */ ret = arch_add_memory(nid, start, size, ¶ms); if (ret < 0) - goto error; + goto error_free; /* create memory block devices after memory was added */ - ret = create_memory_block_devices(start, size, mhp_altmap.free, group); + ret = create_memory_block_devices(start, size, params.altmap, group); if (ret) { arch_remove_memory(start, size, NULL); - goto error; + goto error_free; } if (new_node) { @@ -1490,6 +1496,8 @@ int __ref add_memory_resource(int nid, struct resource *res, mhp_t mhp_flags) walk_memory_blocks(start, size, NULL, online_memory_block); return ret; +error_free: + kfree(params.altmap); error: if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK)) memblock_remove(start, size); @@ -2056,12 +2064,18 @@ static int check_memblock_offlined_cb(struct memory_block *mem, void *arg) return 0; } -static int get_nr_vmemmap_pages_cb(struct memory_block *mem, void *arg) +static int test_has_altmap_cb(struct memory_block *mem, void *arg) { + struct memory_block **mem_ptr = (struct memory_block **)arg; /* - * If not set, continue with the next block. + * return the memblock if we have altmap + * and break callback. */ - return mem->nr_vmemmap_pages; + if (mem->altmap) { + *mem_ptr = mem; + return 1; + } + return 0; } static int check_cpu_on_node(int nid) @@ -2136,10 +2150,9 @@ EXPORT_SYMBOL(try_offline_node); static int __ref try_remove_memory(u64 start, u64 size) { - struct vmem_altmap mhp_altmap = {}; - struct vmem_altmap *altmap = NULL; - unsigned long nr_vmemmap_pages; + struct memory_block *mem; int rc = 0, nid = NUMA_NO_NODE; + struct vmem_altmap *altmap = NULL; BUG_ON(check_hotplug_memory_range(start, size)); @@ -2161,25 +2174,20 @@ static int __ref try_remove_memory(u64 start, u64 size) * the same granularity it was added - a single memory block. */ if (mhp_memmap_on_memory()) { - nr_vmemmap_pages = walk_memory_blocks(start, size, NULL, - get_nr_vmemmap_pages_cb); - if (nr_vmemmap_pages) { + rc = walk_memory_blocks(start, size, &mem, test_has_altmap_cb); + if (rc) { if (size != memory_block_size_bytes()) { pr_warn("Refuse to remove %#llx - %#llx," "wrong granularity\n", start, start + size); return -EINVAL; } - + altmap = mem->altmap; /* - * Let remove_pmd_table->free_hugepage_table do the - * right thing if we used vmem_altmap when hot-adding - * the range. + * Mark altmap NULL so that we can add a debug + * check on memblock free. */ - mhp_altmap.base_pfn = PHYS_PFN(start); - mhp_altmap.free = nr_vmemmap_pages; - mhp_altmap.alloc = nr_vmemmap_pages; - altmap = &mhp_altmap; + mem->altmap = NULL; } } @@ -2196,6 +2204,12 @@ static int __ref try_remove_memory(u64 start, u64 size) arch_remove_memory(start, size, altmap); + /* Verify that all vmemmap pages have actually been freed. */ + if (altmap) { + WARN(altmap->alloc, "Altmap not fully unmapped"); + kfree(altmap); + } + if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK)) { memblock_phys_free(start, size); memblock_remove(start, size);