From 7ea6216049ff9cf250a6722cd766d99c8d1424e5 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Thu, 18 Jul 2019 15:58:22 -0700 Subject: [PATCH] mm/sparsemem: prepare for sub-section ranges MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Prepare the memory hot-{add,remove} paths for handling sub-section ranges by plumbing the starting page frame and number of pages being handled through arch_{add,remove}_memory() to sparse_{add,remove}_one_section(). This is simply plumbing, small cleanups, and some identifier renames. No intended functional changes. Link: http://lkml.kernel.org/r/156092353780.979959.9713046515562743194.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams Reviewed-by: Pavel Tatashin Tested-by: Aneesh Kumar K.V [ppc64] Reviewed-by: Oscar Salvador Cc: Michal Hocko Cc: Vlastimil Babka Cc: Logan Gunthorpe Cc: David Hildenbrand Cc: Jane Chu Cc: Jeff Moyer Cc: Jérôme Glisse Cc: Jonathan Corbet Cc: Mike Rapoport Cc: Toshi Kani Cc: Wei Yang Cc: Jason Gunthorpe Cc: Christoph Hellwig Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/memory_hotplug.h | 5 +- mm/memory_hotplug.c | 114 ++++++++++++++++++++------------- mm/sparse.c | 16 ++--- 3 files changed, 81 insertions(+), 54 deletions(-) diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h index 475aff8efbf8..2d636a7491a4 100644 --- a/include/linux/memory_hotplug.h +++ b/include/linux/memory_hotplug.h @@ -346,9 +346,10 @@ extern int add_memory_resource(int nid, struct resource *resource); 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); -extern int sparse_add_one_section(int nid, unsigned long start_pfn, - struct vmem_altmap *altmap); +extern int sparse_add_section(int nid, unsigned long pfn, + unsigned long nr_pages, struct vmem_altmap *altmap); extern void sparse_remove_one_section(struct mem_section *ms, + unsigned long pfn, unsigned long nr_pages, unsigned long map_offset, struct vmem_altmap *altmap); extern struct page *sparse_decode_mem_map(unsigned long coded_mem_map, unsigned long pnum); diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 11220044b01a..3fbb2cfab126 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -252,51 +252,84 @@ 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, - struct vmem_altmap *altmap) +static int __meminit __add_section(int nid, unsigned long pfn, + unsigned long nr_pages, struct vmem_altmap *altmap) { int ret; - if (pfn_valid(phys_start_pfn)) + if (pfn_valid(pfn)) return -EEXIST; - ret = sparse_add_one_section(nid, phys_start_pfn, altmap); + ret = sparse_add_section(nid, pfn, nr_pages, altmap); return ret < 0 ? ret : 0; } +static int check_pfn_span(unsigned long pfn, unsigned long nr_pages, + const char *reason) +{ + /* + * Disallow all operations smaller than a sub-section and only + * allow operations smaller than a section for + * SPARSEMEM_VMEMMAP. Note that check_hotplug_memory_range() + * enforces a larger memory_block_size_bytes() granularity for + * memory that will be marked online, so this check should only + * fire for direct arch_{add,remove}_memory() users outside of + * add_memory_resource(). + */ + unsigned long min_align; + + if (IS_ENABLED(CONFIG_SPARSEMEM_VMEMMAP)) + min_align = PAGES_PER_SUBSECTION; + else + min_align = PAGES_PER_SECTION; + if (!IS_ALIGNED(pfn, min_align) + || !IS_ALIGNED(nr_pages, min_align)) { + WARN(1, "Misaligned __%s_pages start: %#lx end: #%lx\n", + reason, pfn, pfn + nr_pages - 1); + return -EINVAL; + } + return 0; +} + /* * Reasonably generic function for adding memory. It is * expected that archs that support memory hotplug will * call this function after deciding the zone to which to * add the new pages. */ -int __ref __add_pages(int nid, unsigned long phys_start_pfn, - unsigned long nr_pages, struct mhp_restrictions *restrictions) +int __ref __add_pages(int nid, unsigned long pfn, unsigned long nr_pages, + struct mhp_restrictions *restrictions) { unsigned long i; - int err = 0; - int start_sec, end_sec; + int start_sec, end_sec, err; 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); - end_sec = pfn_to_section_nr(phys_start_pfn + nr_pages - 1); - if (altmap) { /* * Validate altmap is within bounds of the total request */ - if (altmap->base_pfn != phys_start_pfn + if (altmap->base_pfn != pfn || vmem_altmap_offset(altmap) > nr_pages) { pr_warn_once("memory add fail, invalid altmap\n"); - err = -EINVAL; - goto out; + return -EINVAL; } altmap->alloc = 0; } + err = check_pfn_span(pfn, nr_pages, "add"); + if (err) + return err; + + start_sec = pfn_to_section_nr(pfn); + end_sec = pfn_to_section_nr(pfn + nr_pages - 1); for (i = start_sec; i <= end_sec; i++) { - err = __add_section(nid, section_nr_to_pfn(i), altmap); + unsigned long pfns; + + pfns = min(nr_pages, PAGES_PER_SECTION + - (pfn & ~PAGE_SECTION_MASK)); + err = __add_section(nid, pfn, pfns, altmap); + pfn += pfns; + nr_pages -= pfns; /* * EEXIST is finally dealt with by ioresource collision @@ -309,7 +342,6 @@ int __ref __add_pages(int nid, unsigned long phys_start_pfn, cond_resched(); } vmemmap_populate_print_last(); -out: return err; } @@ -487,10 +519,10 @@ static void shrink_pgdat_span(struct pglist_data *pgdat, pgdat->node_spanned_pages = 0; } -static void __remove_zone(struct zone *zone, unsigned long start_pfn) +static void __remove_zone(struct zone *zone, unsigned long start_pfn, + unsigned long nr_pages) { struct pglist_data *pgdat = zone->zone_pgdat; - int nr_pages = PAGES_PER_SECTION; unsigned long flags; pgdat_resize_lock(zone->zone_pgdat, &flags); @@ -499,27 +531,23 @@ static void __remove_zone(struct zone *zone, unsigned long start_pfn) pgdat_resize_unlock(zone->zone_pgdat, &flags); } -static void __remove_section(struct zone *zone, struct mem_section *ms, - unsigned long map_offset, - struct vmem_altmap *altmap) +static void __remove_section(struct zone *zone, unsigned long pfn, + unsigned long nr_pages, unsigned long map_offset, + struct vmem_altmap *altmap) { - unsigned long start_pfn; - int scn_nr; + struct mem_section *ms = __nr_to_section(pfn_to_section_nr(pfn)); if (WARN_ON_ONCE(!valid_section(ms))) return; - scn_nr = __section_nr(ms); - start_pfn = section_nr_to_pfn((unsigned long)scn_nr); - __remove_zone(zone, start_pfn); - - sparse_remove_one_section(ms, map_offset, altmap); + __remove_zone(zone, pfn, nr_pages); + sparse_remove_one_section(ms, pfn, nr_pages, map_offset, altmap); } /** * __remove_pages() - remove sections of pages from a zone * @zone: zone from which pages need to be removed - * @phys_start_pfn: starting pageframe (must be aligned to start of a section) + * @pfn: starting pageframe (must be aligned to start of a section) * @nr_pages: number of pages to remove (must be multiple of section size) * @altmap: alternative device page map or %NULL if default memmap is used * @@ -528,30 +556,30 @@ static void __remove_section(struct zone *zone, struct mem_section *ms, * sure that pages are marked reserved and zones are adjust properly by * calling offline_pages(). */ -void __remove_pages(struct zone *zone, unsigned long phys_start_pfn, +void __remove_pages(struct zone *zone, unsigned long pfn, unsigned long nr_pages, struct vmem_altmap *altmap) { - unsigned long i; unsigned long map_offset = 0; - int sections_to_remove; + int i, start_sec, end_sec; map_offset = vmem_altmap_offset(altmap); clear_zone_contiguous(zone); - /* - * We can only remove entire sections - */ - BUG_ON(phys_start_pfn & ~PAGE_SECTION_MASK); - BUG_ON(nr_pages % PAGES_PER_SECTION); + if (check_pfn_span(pfn, nr_pages, "remove")) + return; - sections_to_remove = nr_pages / PAGES_PER_SECTION; - for (i = 0; i < sections_to_remove; i++) { - unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION; + start_sec = pfn_to_section_nr(pfn); + end_sec = pfn_to_section_nr(pfn + nr_pages - 1); + for (i = start_sec; i <= end_sec; i++) { + unsigned long pfns; cond_resched(); - __remove_section(zone, __pfn_to_section(pfn), map_offset, - altmap); + pfns = min(nr_pages, PAGES_PER_SECTION + - (pfn & ~PAGE_SECTION_MASK)); + __remove_section(zone, pfn, pfns, map_offset, altmap); + pfn += pfns; + nr_pages -= pfns; map_offset = 0; } diff --git a/mm/sparse.c b/mm/sparse.c index 6b01022e23a9..41579b66fff1 100644 --- a/mm/sparse.c +++ b/mm/sparse.c @@ -728,8 +728,8 @@ static void free_map_bootmem(struct page *memmap) * * -EEXIST - Section has been present. * * -ENOMEM - Out of memory. */ -int __meminit sparse_add_one_section(int nid, unsigned long start_pfn, - struct vmem_altmap *altmap) +int __meminit sparse_add_section(int nid, unsigned long start_pfn, + unsigned long nr_pages, struct vmem_altmap *altmap) { unsigned long section_nr = pfn_to_section_nr(start_pfn); struct mem_section_usage *usage; @@ -835,8 +835,9 @@ static void free_section_usage(struct mem_section *ms, struct page *memmap, free_map_bootmem(memmap); } -void sparse_remove_one_section(struct mem_section *ms, unsigned long map_offset, - struct vmem_altmap *altmap) +void sparse_remove_one_section(struct mem_section *ms, unsigned long pfn, + unsigned long nr_pages, unsigned long map_offset, + struct vmem_altmap *altmap) { struct page *memmap = NULL; struct mem_section_usage *usage = NULL; @@ -849,10 +850,7 @@ void sparse_remove_one_section(struct mem_section *ms, unsigned long map_offset, ms->usage = NULL; } - clear_hwpoisoned_pages(memmap + map_offset, - PAGES_PER_SECTION - map_offset); - free_section_usage(ms, memmap, usage, - section_nr_to_pfn(__section_nr(ms)), - PAGES_PER_SECTION, altmap); + clear_hwpoisoned_pages(memmap + map_offset, nr_pages - map_offset); + free_section_usage(ms, memmap, usage, pfn, nr_pages, altmap); } #endif /* CONFIG_MEMORY_HOTPLUG */