Contributors: 61
| Author |
Tokens |
Token Proportion |
Commits |
Commit Proportion |
| Dan J Williams |
645 |
17.13% |
10 |
8.20% |
| Christoph Lameter |
555 |
14.74% |
2 |
1.64% |
| David Hildenbrand (Red Hat) |
433 |
11.50% |
2 |
1.64% |
| Joao Martins |
431 |
11.44% |
3 |
2.46% |
| Andy Whitcroft |
255 |
6.77% |
3 |
2.46% |
| van der Linden, Frank |
228 |
6.05% |
3 |
2.46% |
| Feiyang Chen |
205 |
5.44% |
2 |
1.64% |
| Kiryl Shutsemau |
163 |
4.33% |
1 |
0.82% |
| Christoph Hellwig |
71 |
1.89% |
5 |
4.10% |
| Michal Hocko |
69 |
1.83% |
5 |
4.10% |
| Dave Hansen |
64 |
1.70% |
4 |
3.28% |
| Johannes Weiner |
57 |
1.51% |
3 |
2.46% |
| Linus Torvalds (pre-git) |
57 |
1.51% |
11 |
9.02% |
| Baoquan He |
52 |
1.38% |
4 |
3.28% |
| Kirill A. Shutemov |
51 |
1.35% |
1 |
0.82% |
| Wei Yang |
45 |
1.19% |
6 |
4.92% |
| Anshuman Khandual |
43 |
1.14% |
4 |
3.28% |
| Pavel Tatashin |
33 |
0.88% |
4 |
3.28% |
| Yinghai Lu |
31 |
0.82% |
2 |
1.64% |
| Kamezawa Hiroyuki |
27 |
0.72% |
1 |
0.82% |
| Sourav Panda |
26 |
0.69% |
1 |
0.82% |
| David Woodhouse |
23 |
0.61% |
1 |
0.82% |
| David Rientjes |
16 |
0.42% |
2 |
1.64% |
| Américo Wang |
15 |
0.40% |
1 |
0.82% |
| Huacai Chen |
13 |
0.35% |
1 |
0.82% |
| Yajun Deng |
12 |
0.32% |
1 |
0.82% |
| Yasunori Goto |
12 |
0.32% |
2 |
1.64% |
| Aneesh Kumar K.V |
12 |
0.32% |
2 |
1.64% |
| Ryan Roberts |
12 |
0.32% |
1 |
0.82% |
| Badari Pulavarty |
11 |
0.29% |
1 |
0.82% |
| Song Muchun |
8 |
0.21% |
2 |
1.64% |
| Al Viro |
7 |
0.19% |
2 |
1.64% |
| Sumanth Korikkar |
7 |
0.19% |
1 |
0.82% |
| Harry Yoo |
6 |
0.16% |
1 |
0.82% |
| Jérôme Glisse |
6 |
0.16% |
1 |
0.82% |
| Andrew Morton |
6 |
0.16% |
1 |
0.82% |
| Alexander Duyck |
5 |
0.13% |
1 |
0.82% |
| Bibo Mao |
5 |
0.13% |
1 |
0.82% |
| Dev Jain |
4 |
0.11% |
1 |
0.82% |
| Mel Gorman |
4 |
0.11% |
1 |
0.82% |
| Shaohua Li |
4 |
0.11% |
1 |
0.82% |
| Liu Ping Fan |
4 |
0.11% |
1 |
0.82% |
| David Howells |
3 |
0.08% |
1 |
0.82% |
| guoweikang |
3 |
0.08% |
1 |
0.82% |
| Brent Casavant |
3 |
0.08% |
1 |
0.82% |
| Glauber de Oliveira Costa |
3 |
0.08% |
1 |
0.82% |
| Tang Chen |
3 |
0.08% |
1 |
0.82% |
| 권오훈 |
3 |
0.08% |
1 |
0.82% |
| Paul Mackerras |
2 |
0.05% |
1 |
0.82% |
| Santosh Shilimkar |
2 |
0.05% |
1 |
0.82% |
| Uwe Kleine-König |
1 |
0.03% |
1 |
0.82% |
| Ma Wupeng |
1 |
0.03% |
1 |
0.82% |
| Greg Kroah-Hartman |
1 |
0.03% |
1 |
0.82% |
| Yi Wang |
1 |
0.03% |
1 |
0.82% |
| chengkaitao |
1 |
0.03% |
1 |
0.82% |
| Mike Rapoport |
1 |
0.03% |
1 |
0.82% |
| Linus Torvalds |
1 |
0.03% |
1 |
0.82% |
| Fabian Frederick |
1 |
0.03% |
1 |
0.82% |
| 陈学兵 |
1 |
0.03% |
1 |
0.82% |
| Zhang Yanfei |
1 |
0.03% |
1 |
0.82% |
| Joe Perches |
1 |
0.03% |
1 |
0.82% |
| Total |
3766 |
|
122 |
|
// SPDX-License-Identifier: GPL-2.0
/*
* Virtual Memory Map support
*
* (C) 2007 sgi. Christoph Lameter.
*
* Virtual memory maps allow VM primitives pfn_to_page, page_to_pfn,
* virt_to_page, page_address() to be implemented as a base offset
* calculation without memory access.
*
* However, virtual mappings need a page table and TLBs. Many Linux
* architectures already map their physical space using 1-1 mappings
* via TLBs. For those arches the virtual memory map is essentially
* for free if we use the same page size as the 1-1 mappings. In that
* case the overhead consists of a few additional pages that are
* allocated to create a view of memory for vmemmap.
*
* The architecture is expected to provide a vmemmap_populate() function
* to instantiate the mapping.
*/
#include <linux/mm.h>
#include <linux/mmzone.h>
#include <linux/memblock.h>
#include <linux/memremap.h>
#include <linux/highmem.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/vmalloc.h>
#include <linux/sched.h>
#include <linux/pgalloc.h>
#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)
{
void *ptr;
if (altmap)
return altmap_alloc_block_buf(size, altmap);
ptr = sparse_buffer_alloc(size);
if (!ptr)
ptr = vmemmap_alloc_block(size, node);
return ptr;
}
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);
}
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;
}
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;
}
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;
}
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;
}
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_VMEMMAP
static __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)
{
}
int __weak __meminit vmemmap_check_pmd(pmd_t *pmd, int node,
unsigned long addr, unsigned long next)
{
return 0;
}
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;
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 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 */