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mm/sparse: move memory hotplug bits to sparse-vmemmap.c
Let's move all memory hoptplug related code to sparse-vmemmap.c. We only have to expose sparse_index_init(). While at it, drop the definition of sparse_index_init() for !CONFIG_SPARSEMEM, which is unused, and place the declaration in internal.h. Link: https://lkml.kernel.org/r/20260320-sparsemem_cleanups-v2-15-096addc8800d@kernel.org Signed-off-by: David Hildenbrand (Arm) <david@kernel.org> Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yuanchu Xie <yuanchu@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
David Hildenbrand (Arm)
committed by
Andrew Morton
Andrew Morton
parent
08e5f77c37
commit
738de20c4f
@@ -2370,7 +2370,6 @@ static inline unsigned long next_present_section_nr(unsigned long section_nr)
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#endif
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#else
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#define sparse_index_init(_sec, _nid) do {} while (0)
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#define sparse_vmemmap_init_nid_early(_nid) do {} while (0)
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#define sparse_vmemmap_init_nid_late(_nid) do {} while (0)
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#define pfn_in_present_section pfn_valid
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@@ -964,6 +964,7 @@ void memmap_init_range(unsigned long, int, unsigned long, unsigned long,
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*/
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#ifdef CONFIG_SPARSEMEM
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void sparse_init(void);
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int sparse_index_init(unsigned long section_nr, int nid);
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static inline void sparse_init_one_section(struct mem_section *ms,
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unsigned long pnum, struct page *mem_map,
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@@ -999,6 +1000,9 @@ static inline void __section_mark_present(struct mem_section *ms,
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static inline void sparse_init(void) {}
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#endif /* CONFIG_SPARSEMEM */
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/*
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* mm/sparse-vmemmap.c
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*/
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#ifdef CONFIG_SPARSEMEM_VMEMMAP
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void sparse_init_subsection_map(unsigned long pfn, unsigned long nr_pages);
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#else
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@@ -591,3 +591,307 @@ void __init sparse_vmemmap_init_nid_late(int nid)
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hugetlb_vmemmap_init_late(nid);
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}
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#endif
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static void subsection_mask_set(unsigned long *map, unsigned long pfn,
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unsigned long nr_pages)
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{
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int idx = subsection_map_index(pfn);
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int end = subsection_map_index(pfn + nr_pages - 1);
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bitmap_set(map, idx, end - idx + 1);
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}
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void __init sparse_init_subsection_map(unsigned long pfn, unsigned long nr_pages)
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{
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int end_sec_nr = pfn_to_section_nr(pfn + nr_pages - 1);
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unsigned long nr, start_sec_nr = pfn_to_section_nr(pfn);
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for (nr = start_sec_nr; nr <= end_sec_nr; nr++) {
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struct mem_section *ms;
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unsigned long pfns;
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pfns = min(nr_pages, PAGES_PER_SECTION
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- (pfn & ~PAGE_SECTION_MASK));
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ms = __nr_to_section(nr);
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subsection_mask_set(ms->usage->subsection_map, pfn, pfns);
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pr_debug("%s: sec: %lu pfns: %lu set(%d, %d)\n", __func__, nr,
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pfns, subsection_map_index(pfn),
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subsection_map_index(pfn + pfns - 1));
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pfn += pfns;
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nr_pages -= pfns;
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}
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}
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#ifdef CONFIG_MEMORY_HOTPLUG
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/* Mark all memory sections within the pfn range as online */
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void online_mem_sections(unsigned long start_pfn, unsigned long end_pfn)
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{
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unsigned long pfn;
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for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
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unsigned long section_nr = pfn_to_section_nr(pfn);
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struct mem_section *ms = __nr_to_section(section_nr);
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ms->section_mem_map |= SECTION_IS_ONLINE;
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}
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}
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/* Mark all memory sections within the pfn range as offline */
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void offline_mem_sections(unsigned long start_pfn, unsigned long end_pfn)
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{
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unsigned long pfn;
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for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
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unsigned long section_nr = pfn_to_section_nr(pfn);
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struct mem_section *ms = __nr_to_section(section_nr);
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ms->section_mem_map &= ~SECTION_IS_ONLINE;
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}
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}
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static struct page * __meminit populate_section_memmap(unsigned long pfn,
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unsigned long nr_pages, int nid, struct vmem_altmap *altmap,
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struct dev_pagemap *pgmap)
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{
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return __populate_section_memmap(pfn, nr_pages, nid, altmap, pgmap);
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}
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static void depopulate_section_memmap(unsigned long pfn, unsigned long nr_pages,
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struct vmem_altmap *altmap)
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{
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unsigned long start = (unsigned long) pfn_to_page(pfn);
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unsigned long end = start + nr_pages * sizeof(struct page);
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vmemmap_free(start, end, altmap);
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}
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static void free_map_bootmem(struct page *memmap)
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{
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unsigned long start = (unsigned long)memmap;
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unsigned long end = (unsigned long)(memmap + PAGES_PER_SECTION);
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vmemmap_free(start, end, NULL);
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}
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static int clear_subsection_map(unsigned long pfn, unsigned long nr_pages)
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{
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DECLARE_BITMAP(map, SUBSECTIONS_PER_SECTION) = { 0 };
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DECLARE_BITMAP(tmp, SUBSECTIONS_PER_SECTION) = { 0 };
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struct mem_section *ms = __pfn_to_section(pfn);
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unsigned long *subsection_map = ms->usage
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? &ms->usage->subsection_map[0] : NULL;
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subsection_mask_set(map, pfn, nr_pages);
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if (subsection_map)
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bitmap_and(tmp, map, subsection_map, SUBSECTIONS_PER_SECTION);
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if (WARN(!subsection_map || !bitmap_equal(tmp, map, SUBSECTIONS_PER_SECTION),
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"section already deactivated (%#lx + %ld)\n",
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pfn, nr_pages))
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return -EINVAL;
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bitmap_xor(subsection_map, map, subsection_map, SUBSECTIONS_PER_SECTION);
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return 0;
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}
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static bool is_subsection_map_empty(struct mem_section *ms)
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{
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return bitmap_empty(&ms->usage->subsection_map[0],
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SUBSECTIONS_PER_SECTION);
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}
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static int fill_subsection_map(unsigned long pfn, unsigned long nr_pages)
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{
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struct mem_section *ms = __pfn_to_section(pfn);
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DECLARE_BITMAP(map, SUBSECTIONS_PER_SECTION) = { 0 };
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unsigned long *subsection_map;
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int rc = 0;
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subsection_mask_set(map, pfn, nr_pages);
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subsection_map = &ms->usage->subsection_map[0];
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if (bitmap_empty(map, SUBSECTIONS_PER_SECTION))
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rc = -EINVAL;
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else if (bitmap_intersects(map, subsection_map, SUBSECTIONS_PER_SECTION))
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rc = -EEXIST;
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else
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bitmap_or(subsection_map, map, subsection_map,
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SUBSECTIONS_PER_SECTION);
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return rc;
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}
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/*
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* To deactivate a memory region, there are 3 cases to handle:
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*
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* 1. deactivation of a partial hot-added section:
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* a) section was present at memory init.
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* b) section was hot-added post memory init.
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* 2. deactivation of a complete hot-added section.
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* 3. deactivation of a complete section from memory init.
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*
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* For 1, when subsection_map does not empty we will not be freeing the
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* usage map, but still need to free the vmemmap range.
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*/
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static void section_deactivate(unsigned long pfn, unsigned long nr_pages,
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struct vmem_altmap *altmap)
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{
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struct mem_section *ms = __pfn_to_section(pfn);
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bool section_is_early = early_section(ms);
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struct page *memmap = NULL;
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bool empty;
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if (clear_subsection_map(pfn, nr_pages))
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return;
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empty = is_subsection_map_empty(ms);
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if (empty) {
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/*
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* Mark the section invalid so that valid_section()
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* return false. This prevents code from dereferencing
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* ms->usage array.
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*/
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ms->section_mem_map &= ~SECTION_HAS_MEM_MAP;
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/*
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* When removing an early section, the usage map is kept (as the
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* usage maps of other sections fall into the same page). It
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* will be re-used when re-adding the section - which is then no
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* longer an early section. If the usage map is PageReserved, it
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* was allocated during boot.
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*/
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if (!PageReserved(virt_to_page(ms->usage))) {
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kfree_rcu(ms->usage, rcu);
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WRITE_ONCE(ms->usage, NULL);
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}
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memmap = pfn_to_page(SECTION_ALIGN_DOWN(pfn));
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}
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/*
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* The memmap of early sections is always fully populated. See
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* section_activate() and pfn_valid() .
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*/
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if (!section_is_early) {
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memmap_pages_add(-1L * (DIV_ROUND_UP(nr_pages * sizeof(struct page), PAGE_SIZE)));
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depopulate_section_memmap(pfn, nr_pages, altmap);
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} else if (memmap) {
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memmap_boot_pages_add(-1L * (DIV_ROUND_UP(nr_pages * sizeof(struct page),
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PAGE_SIZE)));
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free_map_bootmem(memmap);
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}
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if (empty)
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ms->section_mem_map = (unsigned long)NULL;
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}
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static struct page * __meminit section_activate(int nid, unsigned long pfn,
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unsigned long nr_pages, struct vmem_altmap *altmap,
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struct dev_pagemap *pgmap)
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{
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struct mem_section *ms = __pfn_to_section(pfn);
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struct mem_section_usage *usage = NULL;
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struct page *memmap;
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int rc;
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if (!ms->usage) {
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usage = kzalloc(mem_section_usage_size(), GFP_KERNEL);
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if (!usage)
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return ERR_PTR(-ENOMEM);
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ms->usage = usage;
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}
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rc = fill_subsection_map(pfn, nr_pages);
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if (rc) {
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if (usage)
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ms->usage = NULL;
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kfree(usage);
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return ERR_PTR(rc);
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}
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/*
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* The early init code does not consider partially populated
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* initial sections, it simply assumes that memory will never be
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* referenced. If we hot-add memory into such a section then we
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* do not need to populate the memmap and can simply reuse what
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* is already there.
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*/
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if (nr_pages < PAGES_PER_SECTION && early_section(ms))
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return pfn_to_page(pfn);
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memmap = populate_section_memmap(pfn, nr_pages, nid, altmap, pgmap);
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if (!memmap) {
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section_deactivate(pfn, nr_pages, altmap);
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return ERR_PTR(-ENOMEM);
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}
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memmap_pages_add(DIV_ROUND_UP(nr_pages * sizeof(struct page), PAGE_SIZE));
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return memmap;
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}
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/**
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* sparse_add_section - add a memory section, or populate an existing one
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* @nid: The node to add section on
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* @start_pfn: start pfn of the memory range
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* @nr_pages: number of pfns to add in the section
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* @altmap: alternate pfns to allocate the memmap backing store
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* @pgmap: alternate compound page geometry for devmap mappings
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*
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* This is only intended for hotplug.
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*
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* Note that only VMEMMAP supports sub-section aligned hotplug,
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* the proper alignment and size are gated by check_pfn_span().
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*
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*
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* Return:
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* * 0 - On success.
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* * -EEXIST - Section has been present.
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* * -ENOMEM - Out of memory.
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*/
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int __meminit sparse_add_section(int nid, unsigned long start_pfn,
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unsigned long nr_pages, struct vmem_altmap *altmap,
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struct dev_pagemap *pgmap)
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{
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unsigned long section_nr = pfn_to_section_nr(start_pfn);
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struct mem_section *ms;
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struct page *memmap;
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int ret;
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ret = sparse_index_init(section_nr, nid);
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if (ret < 0)
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return ret;
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memmap = section_activate(nid, start_pfn, nr_pages, altmap, pgmap);
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if (IS_ERR(memmap))
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return PTR_ERR(memmap);
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/*
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* Poison uninitialized struct pages in order to catch invalid flags
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* combinations.
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*/
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page_init_poison(memmap, sizeof(struct page) * nr_pages);
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ms = __nr_to_section(section_nr);
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__section_mark_present(ms, section_nr);
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/* Align memmap to section boundary in the subsection case */
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if (section_nr_to_pfn(section_nr) != start_pfn)
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memmap = pfn_to_page(section_nr_to_pfn(section_nr));
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sparse_init_one_section(ms, section_nr, memmap, ms->usage, 0);
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return 0;
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}
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void sparse_remove_section(unsigned long pfn, unsigned long nr_pages,
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struct vmem_altmap *altmap)
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{
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struct mem_section *ms = __pfn_to_section(pfn);
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if (WARN_ON_ONCE(!valid_section(ms)))
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return;
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section_deactivate(pfn, nr_pages, altmap);
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}
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#endif /* CONFIG_MEMORY_HOTPLUG */
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310
mm/sparse.c
310
mm/sparse.c
@@ -79,7 +79,7 @@ static noinline struct mem_section __ref *sparse_index_alloc(int nid)
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return section;
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}
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static int __meminit sparse_index_init(unsigned long section_nr, int nid)
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int __meminit sparse_index_init(unsigned long section_nr, int nid)
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{
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unsigned long root = SECTION_NR_TO_ROOT(section_nr);
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struct mem_section *section;
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@@ -103,7 +103,7 @@ static int __meminit sparse_index_init(unsigned long section_nr, int nid)
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return 0;
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}
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#else /* !SPARSEMEM_EXTREME */
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static inline int sparse_index_init(unsigned long section_nr, int nid)
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int sparse_index_init(unsigned long section_nr, int nid)
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{
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return 0;
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}
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@@ -167,40 +167,6 @@ static inline unsigned long first_present_section_nr(void)
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return next_present_section_nr(-1);
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}
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#ifdef CONFIG_SPARSEMEM_VMEMMAP
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static void subsection_mask_set(unsigned long *map, unsigned long pfn,
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unsigned long nr_pages)
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{
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int idx = subsection_map_index(pfn);
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int end = subsection_map_index(pfn + nr_pages - 1);
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bitmap_set(map, idx, end - idx + 1);
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}
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void __init sparse_init_subsection_map(unsigned long pfn, unsigned long nr_pages)
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{
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int end_sec_nr = pfn_to_section_nr(pfn + nr_pages - 1);
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unsigned long nr, start_sec_nr = pfn_to_section_nr(pfn);
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for (nr = start_sec_nr; nr <= end_sec_nr; nr++) {
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struct mem_section *ms;
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unsigned long pfns;
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pfns = min(nr_pages, PAGES_PER_SECTION
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- (pfn & ~PAGE_SECTION_MASK));
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ms = __nr_to_section(nr);
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subsection_mask_set(ms->usage->subsection_map, pfn, pfns);
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pr_debug("%s: sec: %lu pfns: %lu set(%d, %d)\n", __func__, nr,
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pfns, subsection_map_index(pfn),
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subsection_map_index(pfn + pfns - 1));
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pfn += pfns;
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nr_pages -= pfns;
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}
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}
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#endif
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/* Record a memory area against a node. */
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static void __init memory_present(int nid, unsigned long start, unsigned long end)
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{
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@@ -482,275 +448,3 @@ void __init sparse_init(void)
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sparse_init_nid(nid_begin, pnum_begin, pnum_end, map_count);
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vmemmap_populate_print_last();
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}
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#ifdef CONFIG_MEMORY_HOTPLUG
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/* Mark all memory sections within the pfn range as online */
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void online_mem_sections(unsigned long start_pfn, unsigned long end_pfn)
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{
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unsigned long pfn;
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for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
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unsigned long section_nr = pfn_to_section_nr(pfn);
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struct mem_section *ms = __nr_to_section(section_nr);
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ms->section_mem_map |= SECTION_IS_ONLINE;
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}
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}
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/* Mark all memory sections within the pfn range as offline */
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void offline_mem_sections(unsigned long start_pfn, unsigned long end_pfn)
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{
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unsigned long pfn;
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for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
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unsigned long section_nr = pfn_to_section_nr(pfn);
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struct mem_section *ms = __nr_to_section(section_nr);
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ms->section_mem_map &= ~SECTION_IS_ONLINE;
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}
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}
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|
||||
static struct page * __meminit populate_section_memmap(unsigned long pfn,
|
||||
unsigned long nr_pages, int nid, struct vmem_altmap *altmap,
|
||||
struct dev_pagemap *pgmap)
|
||||
{
|
||||
return __populate_section_memmap(pfn, nr_pages, nid, altmap, pgmap);
|
||||
}
|
||||
|
||||
static void depopulate_section_memmap(unsigned long pfn, unsigned long nr_pages,
|
||||
struct vmem_altmap *altmap)
|
||||
{
|
||||
unsigned long start = (unsigned long) pfn_to_page(pfn);
|
||||
unsigned long end = start + nr_pages * sizeof(struct page);
|
||||
|
||||
vmemmap_free(start, end, altmap);
|
||||
}
|
||||
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, NULL);
|
||||
}
|
||||
|
||||
static int clear_subsection_map(unsigned long pfn, unsigned long nr_pages)
|
||||
{
|
||||
DECLARE_BITMAP(map, SUBSECTIONS_PER_SECTION) = { 0 };
|
||||
DECLARE_BITMAP(tmp, SUBSECTIONS_PER_SECTION) = { 0 };
|
||||
struct mem_section *ms = __pfn_to_section(pfn);
|
||||
unsigned long *subsection_map = ms->usage
|
||||
? &ms->usage->subsection_map[0] : NULL;
|
||||
|
||||
subsection_mask_set(map, pfn, nr_pages);
|
||||
if (subsection_map)
|
||||
bitmap_and(tmp, map, subsection_map, SUBSECTIONS_PER_SECTION);
|
||||
|
||||
if (WARN(!subsection_map || !bitmap_equal(tmp, map, SUBSECTIONS_PER_SECTION),
|
||||
"section already deactivated (%#lx + %ld)\n",
|
||||
pfn, nr_pages))
|
||||
return -EINVAL;
|
||||
|
||||
bitmap_xor(subsection_map, map, subsection_map, SUBSECTIONS_PER_SECTION);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static bool is_subsection_map_empty(struct mem_section *ms)
|
||||
{
|
||||
return bitmap_empty(&ms->usage->subsection_map[0],
|
||||
SUBSECTIONS_PER_SECTION);
|
||||
}
|
||||
|
||||
static int fill_subsection_map(unsigned long pfn, unsigned long nr_pages)
|
||||
{
|
||||
struct mem_section *ms = __pfn_to_section(pfn);
|
||||
DECLARE_BITMAP(map, SUBSECTIONS_PER_SECTION) = { 0 };
|
||||
unsigned long *subsection_map;
|
||||
int rc = 0;
|
||||
|
||||
subsection_mask_set(map, pfn, nr_pages);
|
||||
|
||||
subsection_map = &ms->usage->subsection_map[0];
|
||||
|
||||
if (bitmap_empty(map, SUBSECTIONS_PER_SECTION))
|
||||
rc = -EINVAL;
|
||||
else if (bitmap_intersects(map, subsection_map, SUBSECTIONS_PER_SECTION))
|
||||
rc = -EEXIST;
|
||||
else
|
||||
bitmap_or(subsection_map, map, subsection_map,
|
||||
SUBSECTIONS_PER_SECTION);
|
||||
|
||||
return rc;
|
||||
}
|
||||
|
||||
/*
|
||||
* To deactivate a memory region, there are 3 cases to handle:
|
||||
*
|
||||
* 1. deactivation of a partial hot-added section:
|
||||
* a) section was present at memory init.
|
||||
* b) section was hot-added post memory init.
|
||||
* 2. deactivation of a complete hot-added section.
|
||||
* 3. deactivation of a complete section from memory init.
|
||||
*
|
||||
* For 1, when subsection_map does not empty we will not be freeing the
|
||||
* usage map, but still need to free the vmemmap range.
|
||||
*/
|
||||
static void section_deactivate(unsigned long pfn, unsigned long nr_pages,
|
||||
struct vmem_altmap *altmap)
|
||||
{
|
||||
struct mem_section *ms = __pfn_to_section(pfn);
|
||||
bool section_is_early = early_section(ms);
|
||||
struct page *memmap = NULL;
|
||||
bool empty;
|
||||
|
||||
if (clear_subsection_map(pfn, nr_pages))
|
||||
return;
|
||||
|
||||
empty = is_subsection_map_empty(ms);
|
||||
if (empty) {
|
||||
/*
|
||||
* Mark the section invalid so that valid_section()
|
||||
* return false. This prevents code from dereferencing
|
||||
* ms->usage array.
|
||||
*/
|
||||
ms->section_mem_map &= ~SECTION_HAS_MEM_MAP;
|
||||
|
||||
/*
|
||||
* When removing an early section, the usage map is kept (as the
|
||||
* usage maps of other sections fall into the same page). It
|
||||
* will be re-used when re-adding the section - which is then no
|
||||
* longer an early section. If the usage map is PageReserved, it
|
||||
* was allocated during boot.
|
||||
*/
|
||||
if (!PageReserved(virt_to_page(ms->usage))) {
|
||||
kfree_rcu(ms->usage, rcu);
|
||||
WRITE_ONCE(ms->usage, NULL);
|
||||
}
|
||||
memmap = pfn_to_page(SECTION_ALIGN_DOWN(pfn));
|
||||
}
|
||||
|
||||
/*
|
||||
* The memmap of early sections is always fully populated. See
|
||||
* section_activate() and pfn_valid() .
|
||||
*/
|
||||
if (!section_is_early) {
|
||||
memmap_pages_add(-1L * (DIV_ROUND_UP(nr_pages * sizeof(struct page), PAGE_SIZE)));
|
||||
depopulate_section_memmap(pfn, nr_pages, altmap);
|
||||
} else if (memmap) {
|
||||
memmap_boot_pages_add(-1L * (DIV_ROUND_UP(nr_pages * sizeof(struct page),
|
||||
PAGE_SIZE)));
|
||||
free_map_bootmem(memmap);
|
||||
}
|
||||
|
||||
if (empty)
|
||||
ms->section_mem_map = (unsigned long)NULL;
|
||||
}
|
||||
|
||||
static struct page * __meminit section_activate(int nid, unsigned long pfn,
|
||||
unsigned long nr_pages, struct vmem_altmap *altmap,
|
||||
struct dev_pagemap *pgmap)
|
||||
{
|
||||
struct mem_section *ms = __pfn_to_section(pfn);
|
||||
struct mem_section_usage *usage = NULL;
|
||||
struct page *memmap;
|
||||
int rc;
|
||||
|
||||
if (!ms->usage) {
|
||||
usage = kzalloc(mem_section_usage_size(), GFP_KERNEL);
|
||||
if (!usage)
|
||||
return ERR_PTR(-ENOMEM);
|
||||
ms->usage = usage;
|
||||
}
|
||||
|
||||
rc = fill_subsection_map(pfn, nr_pages);
|
||||
if (rc) {
|
||||
if (usage)
|
||||
ms->usage = NULL;
|
||||
kfree(usage);
|
||||
return ERR_PTR(rc);
|
||||
}
|
||||
|
||||
/*
|
||||
* The early init code does not consider partially populated
|
||||
* initial sections, it simply assumes that memory will never be
|
||||
* referenced. If we hot-add memory into such a section then we
|
||||
* do not need to populate the memmap and can simply reuse what
|
||||
* is already there.
|
||||
*/
|
||||
if (nr_pages < PAGES_PER_SECTION && early_section(ms))
|
||||
return pfn_to_page(pfn);
|
||||
|
||||
memmap = populate_section_memmap(pfn, nr_pages, nid, altmap, pgmap);
|
||||
if (!memmap) {
|
||||
section_deactivate(pfn, nr_pages, altmap);
|
||||
return ERR_PTR(-ENOMEM);
|
||||
}
|
||||
memmap_pages_add(DIV_ROUND_UP(nr_pages * sizeof(struct page), PAGE_SIZE));
|
||||
|
||||
return memmap;
|
||||
}
|
||||
|
||||
/**
|
||||
* sparse_add_section - add a memory section, or populate an existing one
|
||||
* @nid: The node to add section on
|
||||
* @start_pfn: start pfn of the memory range
|
||||
* @nr_pages: number of pfns to add in the section
|
||||
* @altmap: alternate pfns to allocate the memmap backing store
|
||||
* @pgmap: alternate compound page geometry for devmap mappings
|
||||
*
|
||||
* This is only intended for hotplug.
|
||||
*
|
||||
* Note that only VMEMMAP supports sub-section aligned hotplug,
|
||||
* the proper alignment and size are gated by check_pfn_span().
|
||||
*
|
||||
*
|
||||
* Return:
|
||||
* * 0 - On success.
|
||||
* * -EEXIST - Section has been present.
|
||||
* * -ENOMEM - Out of memory.
|
||||
*/
|
||||
int __meminit sparse_add_section(int nid, unsigned long start_pfn,
|
||||
unsigned long nr_pages, struct vmem_altmap *altmap,
|
||||
struct dev_pagemap *pgmap)
|
||||
{
|
||||
unsigned long section_nr = pfn_to_section_nr(start_pfn);
|
||||
struct mem_section *ms;
|
||||
struct page *memmap;
|
||||
int ret;
|
||||
|
||||
ret = sparse_index_init(section_nr, nid);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
memmap = section_activate(nid, start_pfn, nr_pages, altmap, pgmap);
|
||||
if (IS_ERR(memmap))
|
||||
return PTR_ERR(memmap);
|
||||
|
||||
/*
|
||||
* Poison uninitialized struct pages in order to catch invalid flags
|
||||
* combinations.
|
||||
*/
|
||||
page_init_poison(memmap, sizeof(struct page) * nr_pages);
|
||||
|
||||
ms = __nr_to_section(section_nr);
|
||||
__section_mark_present(ms, section_nr);
|
||||
|
||||
/* Align memmap to section boundary in the subsection case */
|
||||
if (section_nr_to_pfn(section_nr) != start_pfn)
|
||||
memmap = pfn_to_page(section_nr_to_pfn(section_nr));
|
||||
sparse_init_one_section(ms, section_nr, memmap, ms->usage, 0);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
void sparse_remove_section(unsigned long pfn, unsigned long nr_pages,
|
||||
struct vmem_altmap *altmap)
|
||||
{
|
||||
struct mem_section *ms = __pfn_to_section(pfn);
|
||||
|
||||
if (WARN_ON_ONCE(!valid_section(ms)))
|
||||
return;
|
||||
|
||||
section_deactivate(pfn, nr_pages, altmap);
|
||||
}
|
||||
#endif /* CONFIG_MEMORY_HOTPLUG */
|
||||
|
||||
Reference in New Issue
Block a user