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Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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#include <asm/dma.h>#include <asm/tlbflush.h>
#include "hugetlb_vmemmap.h"
/* * Flags for vmemmap_populate_range and friends. *//* Get a ref on the head page struct page, for ZONE_DEVICE compound pages */#define VMEMMAP_POPULATE_PAGEREF 0x0001
#include "internal.h"
/* * Allocate a block of memory to be used to back the virtual memory map * or to back the page tables that are used to create the mapping. * Uses the main allocators if they are available, else bootmem. */
static void * __ref __earlyonly_bootmem_alloc(int node, unsigned long size, unsigned long align, unsigned long goal){ return memmap_alloc(size, align, goal, node, false);}
void * __meminit vmemmap_alloc_block(unsigned long size, int node){ /* If the main allocator is up use that, fallback to bootmem. */ if (slab_is_available()) { gfp_t gfp_mask = GFP_KERNEL|__GFP_RETRY_MAYFAIL|__GFP_NOWARN; int order = get_order(size); static bool warned __meminitdata; struct page *page;
page = alloc_pages_node(node, gfp_mask, order); if (page) return page_address(page);
if (!warned) { warn_alloc(gfp_mask & ~__GFP_NOWARN, NULL, "vmemmap alloc failure: order:%u", order); warned = true; } return NULL; } else return __earlyonly_bootmem_alloc(node, size, size, __pa(MAX_DMA_ADDRESS));}
static void * __meminit altmap_alloc_block_buf(unsigned long size, struct vmem_altmap *altmap);
/* 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 vmemmap_alloc_block(size, node);}
static unsigned long __meminit vmem_altmap_next_pfn(struct vmem_altmap *altmap){ return altmap->base_pfn + altmap->reserve + altmap->alloc + altmap->align;}
static unsigned long __meminit vmem_altmap_nr_free(struct vmem_altmap *altmap){ unsigned long allocated = altmap->alloc + altmap->align;
if (altmap->free > allocated) return altmap->free - allocated; return 0;}
static void * __meminit altmap_alloc_block_buf(unsigned long size, struct vmem_altmap *altmap){ unsigned long pfn, nr_pfns, nr_align;
if (size & ~PAGE_MASK) { pr_warn_once("%s: allocations must be multiple of PAGE_SIZE (%ld)\n", __func__, size); return NULL; }
pfn = vmem_altmap_next_pfn(altmap); nr_pfns = size >> PAGE_SHIFT; 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 __va(__pfn_to_phys(pfn));}
void __meminit vmemmap_verify(pte_t *pte, int node, unsigned long start, unsigned long end){ unsigned long pfn = pte_pfn(ptep_get(pte)); int actual_node = early_pfn_to_nid(pfn);
if (node_distance(actual_node, node) > LOCAL_DISTANCE) pr_warn_once("[%lx-%lx] potential offnode page_structs\n", start, end - 1);}
static pte_t * __meminit vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node, struct vmem_altmap *altmap, unsigned long ptpfn, unsigned long flags){ pte_t *pte = pte_offset_kernel(pmd, addr); if (pte_none(ptep_get(pte))) { pte_t entry; void *p;
if (ptpfn == (unsigned long)-1) { p = vmemmap_alloc_block_buf(PAGE_SIZE, node, altmap); if (!p) return NULL; ptpfn = PHYS_PFN(__pa(p)); } else { /* * When a PTE/PMD entry is freed from the init_mm * there's a free_pages() call to this page allocated * above. Thus this get_page() is paired with the * put_page_testzero() on the freeing path. * This can only called by certain ZONE_DEVICE path, * and through vmemmap_populate_compound_pages() when * slab is available. */ if (flags & VMEMMAP_POPULATE_PAGEREF) get_page(pfn_to_page(ptpfn)); } entry = pfn_pte(ptpfn, PAGE_KERNEL); set_pte_at(&init_mm, addr, pte, entry); } return pte;}
static void * __meminit vmemmap_alloc_block_zero(unsigned long size, int node){ void *p = vmemmap_alloc_block(size, node);
if (!p) return NULL; memset(p, 0, size);
return p;}
static pmd_t * __meminit vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node){ pmd_t *pmd = pmd_offset(pud, addr); if (pmd_none(*pmd)) { void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node); if (!p) return NULL; kernel_pte_init(p); pmd_populate_kernel(&init_mm, pmd, p); } return pmd;}
static pud_t * __meminit vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node){ pud_t *pud = pud_offset(p4d, addr); if (pud_none(*pud)) { void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node); if (!p) return NULL; pmd_init(p); pud_populate(&init_mm, pud, p); } return pud;}
static p4d_t * __meminit vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node){ p4d_t *p4d = p4d_offset(pgd, addr); if (p4d_none(*p4d)) { void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node); if (!p) return NULL; pud_init(p); p4d_populate_kernel(addr, p4d, p); } return p4d;}
static pgd_t * __meminit vmemmap_pgd_populate(unsigned long addr, int node){ pgd_t *pgd = pgd_offset_k(addr); if (pgd_none(*pgd)) { void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node); if (!p) return NULL; pgd_populate_kernel(addr, pgd, p); } return pgd;}
static pte_t * __meminit vmemmap_populate_address(unsigned long addr, int node, struct vmem_altmap *altmap, unsigned long ptpfn, unsigned long flags){ pgd_t *pgd; p4d_t *p4d; pud_t *pud; pmd_t *pmd; pte_t *pte;
pgd = vmemmap_pgd_populate(addr, node); if (!pgd) return NULL; p4d = vmemmap_p4d_populate(pgd, addr, node); if (!p4d) return NULL; pud = vmemmap_pud_populate(p4d, addr, node); if (!pud) return NULL; pmd = vmemmap_pmd_populate(pud, addr, node); if (!pmd) return NULL; pte = vmemmap_pte_populate(pmd, addr, node, altmap, ptpfn, flags); if (!pte) return NULL; vmemmap_verify(pte, node, addr, addr + PAGE_SIZE);
return pte;}
static int __meminit vmemmap_populate_range(unsigned long start, unsigned long end, int node, struct vmem_altmap *altmap, unsigned long ptpfn, unsigned long flags){ unsigned long addr = start; pte_t *pte;
for (; addr < end; addr += PAGE_SIZE) { pte = vmemmap_populate_address(addr, node, altmap, ptpfn, flags); if (!pte) return -ENOMEM; }
return 0;}
int __meminit vmemmap_populate_basepages(unsigned long start, unsigned long end, int node, struct vmem_altmap *altmap){ return vmemmap_populate_range(start, end, node, altmap, -1, 0);}
/* * Write protect the mirrored tail page structs for HVO. This will be * called from the hugetlb code when gathering and initializing the * memblock allocated gigantic pages. The write protect can't be * done earlier, since it can't be guaranteed that the reserved * page structures will not be written to during initialization, * even if CONFIG_DEFERRED_STRUCT_PAGE_INIT is enabled. * * The PTEs are known to exist, and nothing else should be touching * these pages. The caller is responsible for any TLB flushing. */void vmemmap_wrprotect_hvo(unsigned long addr, unsigned long end, int node, unsigned long headsize){ unsigned long maddr; pte_t *pte;
for (maddr = addr + headsize; maddr < end; maddr += PAGE_SIZE) { pte = virt_to_kpte(maddr); ptep_set_wrprotect(&init_mm, maddr, pte); }}
#ifdef CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAPstatic __meminit struct page *vmemmap_get_tail(unsigned int order, struct zone *zone){ struct page *p, *tail; unsigned int idx; int node = zone_to_nid(zone);
if (WARN_ON_ONCE(order < VMEMMAP_TAIL_MIN_ORDER)) return NULL; if (WARN_ON_ONCE(order > MAX_FOLIO_ORDER)) return NULL;
idx = order - VMEMMAP_TAIL_MIN_ORDER; tail = zone->vmemmap_tails[idx]; if (tail) return tail;
/* * Only allocate the page, but do not initialize it. * * Any initialization done here will be overwritten by memmap_init(). * * hugetlb_vmemmap_init() will take care of initialization after * memmap_init(). */
p = vmemmap_alloc_block_zero(PAGE_SIZE, node); if (!p) return NULL;
tail = virt_to_page(p); zone->vmemmap_tails[idx] = tail;
return tail;}
int __meminit vmemmap_populate_hvo(unsigned long addr, unsigned long end, unsigned int order, struct zone *zone, unsigned long headsize){ unsigned long maddr; struct page *tail; pte_t *pte; int node = zone_to_nid(zone);
tail = vmemmap_get_tail(order, zone); if (!tail) return -ENOMEM;
for (maddr = addr; maddr < addr + headsize; maddr += PAGE_SIZE) { pte = vmemmap_populate_address(maddr, node, NULL, -1, 0); if (!pte) return -ENOMEM; }
/* * Reuse the last page struct page mapped above for the rest. */ return vmemmap_populate_range(maddr, end, node, NULL, page_to_pfn(tail), 0);}#endif
void __weak __meminit vmemmap_set_pmd(pmd_t *pmd, void *p, int node, unsigned long addr, unsigned long next){ WARN_ON_ONCE(!pmd_set_huge(pmd, virt_to_phys(p), PAGE_KERNEL));}
int __weak __meminit vmemmap_check_pmd(pmd_t *pmd, int node, unsigned long addr, unsigned long next){ if (!pmd_leaf(pmdp_get(pmd))) return 0; vmemmap_verify((pte_t *)pmd, node, addr, next);
return 1;}
int __meminit vmemmap_populate_hugepages(unsigned long start, unsigned long end, int node, struct vmem_altmap *altmap){ unsigned long addr; unsigned long next; pgd_t *pgd; p4d_t *p4d; pud_t *pud; pmd_t *pmd;
for (addr = start; addr < end; addr = next) { next = pmd_addr_end(addr, end);
pgd = vmemmap_pgd_populate(addr, node); if (!pgd) return -ENOMEM;
p4d = vmemmap_p4d_populate(pgd, addr, node); if (!p4d) return -ENOMEM;
pud = vmemmap_pud_populate(p4d, addr, node); if (!pud) return -ENOMEM;
pmd = pmd_offset(pud, addr); if (pmd_none(pmdp_get(pmd))) { void *p;
p = vmemmap_alloc_block_buf(PMD_SIZE, node, altmap); if (p) { vmemmap_set_pmd(pmd, p, node, addr, next); continue; } else if (altmap) { /* * No fallback: In any case we care about, the * altmap should be reasonably sized and aligned * such that vmemmap_alloc_block_buf() will always * succeed. For consistency with the PTE case, * return an error here as failure could indicate * a configuration issue with the size of the altmap. */ return -ENOMEM; } } else if (vmemmap_check_pmd(pmd, node, addr, next)) continue; if (vmemmap_populate_basepages(addr, next, node, altmap)) return -ENOMEM; } return 0;}
#ifndef vmemmap_populate_compound_pages/* * For compound pages bigger than section size (e.g. x86 1G compound * pages with 2M subsection size) fill the rest of sections as tail * pages. * * Note that memremap_pages() resets @nr_range value and will increment * it after each range successful onlining. Thus the value or @nr_range * at section memmap populate corresponds to the in-progress range * being onlined here. */static bool __meminit reuse_compound_section(unsigned long start_pfn, struct dev_pagemap *pgmap){ unsigned long nr_pages = pgmap_vmemmap_nr(pgmap); unsigned long offset = start_pfn - PHYS_PFN(pgmap->ranges[pgmap->nr_range].start);
return !IS_ALIGNED(offset, nr_pages) && nr_pages > PAGES_PER_SUBSECTION;}
static pte_t * __meminit compound_section_tail_page(unsigned long addr){ pte_t *pte;
addr -= PAGE_SIZE;
/* * Assuming sections are populated sequentially, the previous section's * page data can be reused. */ pte = pte_offset_kernel(pmd_off_k(addr), addr); if (!pte) return NULL;
return pte;}
static int __meminit vmemmap_populate_compound_pages(unsigned long start_pfn, unsigned long start, unsigned long end, int node, struct dev_pagemap *pgmap){ unsigned long size, addr; pte_t *pte; int rc;
if (reuse_compound_section(start_pfn, pgmap)) { pte = compound_section_tail_page(start); if (!pte) return -ENOMEM;
/* * Reuse the page that was populated in the prior iteration * with just tail struct pages. */ return vmemmap_populate_range(start, end, node, NULL, pte_pfn(ptep_get(pte)), VMEMMAP_POPULATE_PAGEREF); }
size = min(end - start, pgmap_vmemmap_nr(pgmap) * sizeof(struct page)); for (addr = start; addr < end; addr += size) { unsigned long next, last = addr + size;
/* Populate the head page vmemmap page */ pte = vmemmap_populate_address(addr, node, NULL, -1, 0); if (!pte) return -ENOMEM;
/* Populate the tail pages vmemmap page */ next = addr + PAGE_SIZE; pte = vmemmap_populate_address(next, node, NULL, -1, 0); if (!pte) return -ENOMEM;
/* * Reuse the previous page for the rest of tail pages * See layout diagram in Documentation/mm/vmemmap_dedup.rst */ next += PAGE_SIZE; rc = vmemmap_populate_range(next, last, node, NULL, pte_pfn(ptep_get(pte)), VMEMMAP_POPULATE_PAGEREF); if (rc) return -ENOMEM; }
return 0;}
#endif
struct page * __meminit __populate_section_memmap(unsigned long pfn, unsigned long nr_pages, int nid, struct vmem_altmap *altmap, struct dev_pagemap *pgmap){ unsigned long start = (unsigned long) pfn_to_page(pfn); unsigned long end = start + nr_pages * sizeof(struct page); int r;
if (WARN_ON_ONCE(!IS_ALIGNED(pfn, PAGES_PER_SUBSECTION) || !IS_ALIGNED(nr_pages, PAGES_PER_SUBSECTION))) return NULL;
if (vmemmap_can_optimize(altmap, pgmap)) r = vmemmap_populate_compound_pages(pfn, start, end, nid, pgmap); else r = vmemmap_populate(start, end, nid, altmap);
if (r < 0) return NULL;
flush_cache_vmap(start, end);
return pfn_to_page(pfn);}
#ifdef CONFIG_SPARSEMEM_VMEMMAP_PREINIT/* * This is called just before initializing sections for a NUMA node. * Any special initialization that needs to be done before the * generic initialization can be done from here. Sections that * are initialized in hooks called from here will be skipped by * the generic initialization. */void __init sparse_vmemmap_init_nid_early(int nid){ hugetlb_vmemmap_init_early(nid);}
/* * This is called just before the initialization of page structures * through memmap_init. Zones are now initialized, so any work that * needs to be done that needs zone information can be done from * here. */void __init sparse_vmemmap_init_nid_late(int nid){ hugetlb_vmemmap_init_late(nid);}#endif
static void subsection_mask_set(unsigned long *map, unsigned long pfn, unsigned long nr_pages){ int idx = subsection_map_index(pfn); int end = subsection_map_index(pfn + nr_pages - 1);
bitmap_set(map, idx, end - idx + 1);}
void __init sparse_init_subsection_map(unsigned long pfn, unsigned long nr_pages){ int end_sec_nr = pfn_to_section_nr(pfn + nr_pages - 1); unsigned long nr, start_sec_nr = pfn_to_section_nr(pfn);
for (nr = start_sec_nr; nr <= end_sec_nr; nr++) { struct mem_section *ms; unsigned long pfns;
pfns = min(nr_pages, PAGES_PER_SECTION - (pfn & ~PAGE_SECTION_MASK)); ms = __nr_to_section(nr); subsection_mask_set(ms->usage->subsection_map, pfn, pfns);
pr_debug("%s: sec: %lu pfns: %lu set(%d, %d)\n", __func__, nr, pfns, subsection_map_index(pfn), subsection_map_index(pfn + pfns - 1));
pfn += pfns; nr_pages -= pfns; }}
#ifdef CONFIG_MEMORY_HOTPLUG
/* Mark all memory sections within the pfn range as online */void online_mem_sections(unsigned long start_pfn, unsigned long end_pfn){ unsigned long pfn;
for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) { unsigned long section_nr = pfn_to_section_nr(pfn); struct mem_section *ms = __nr_to_section(section_nr);
ms->section_mem_map |= SECTION_IS_ONLINE; }}
/* Mark all memory sections within the pfn range as offline */void offline_mem_sections(unsigned long start_pfn, unsigned long end_pfn){ unsigned long pfn;
for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) { unsigned long section_nr = pfn_to_section_nr(pfn); struct mem_section *ms = __nr_to_section(section_nr);
ms->section_mem_map &= ~SECTION_IS_ONLINE; }}
static int __meminit section_nr_vmemmap_pages(unsigned long pfn, unsigned long nr_pages, struct vmem_altmap *altmap, struct dev_pagemap *pgmap){ const unsigned int order = pgmap ? pgmap->vmemmap_shift : 0; const unsigned long pages_per_compound = 1UL << order;
VM_WARN_ON_ONCE(!IS_ALIGNED(pfn | nr_pages, PAGES_PER_SUBSECTION)); VM_WARN_ON_ONCE(nr_pages > PAGES_PER_SECTION);
if (!vmemmap_can_optimize(altmap, pgmap)) return DIV_ROUND_UP(nr_pages * sizeof(struct page), PAGE_SIZE);
if (order < PFN_SECTION_SHIFT) { VM_WARN_ON_ONCE(!IS_ALIGNED(pfn | nr_pages, pages_per_compound)); return VMEMMAP_RESERVE_NR * nr_pages / pages_per_compound; }
VM_WARN_ON_ONCE(!IS_ALIGNED(pfn | nr_pages, PAGES_PER_SECTION));
if (IS_ALIGNED(pfn, pages_per_compound)) return VMEMMAP_RESERVE_NR;
return 0;}
static struct page * __meminit populate_section_memmap(unsigned long pfn, unsigned long nr_pages, int nid, struct vmem_altmap *altmap, struct dev_pagemap *pgmap){ struct page *page = __populate_section_memmap(pfn, nr_pages, nid, altmap, pgmap);
memmap_pages_add(section_nr_vmemmap_pages(pfn, nr_pages, altmap, pgmap));
return page;}
static void depopulate_section_memmap(unsigned long pfn, unsigned long nr_pages, struct vmem_altmap *altmap, struct dev_pagemap *pgmap){ unsigned long start = (unsigned long) pfn_to_page(pfn); unsigned long end = start + nr_pages * sizeof(struct page);
memmap_pages_add(-section_nr_vmemmap_pages(pfn, nr_pages, altmap, pgmap)); 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); unsigned long pfn = page_to_pfn(memmap);
memmap_boot_pages_add(-section_nr_vmemmap_pages(pfn, PAGES_PER_SECTION, NULL, NULL)); 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 dev_pagemap *pgmap){ 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) depopulate_section_memmap(pfn, nr_pages, altmap, pgmap); else if (memmap) 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, pgmap); return ERR_PTR(-ENOMEM); }
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 dev_pagemap *pgmap){ struct mem_section *ms = __pfn_to_section(pfn);
if (WARN_ON_ONCE(!valid_section(ms))) return;
section_deactivate(pfn, nr_pages, altmap, pgmap);}#endif /* CONFIG_MEMORY_HOTPLUG */