[linux.git] / mm / sparse-vmemmap.c

// 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/bootmem.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 <asm/dma.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.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 memblock_virt_alloc_try_nid_raw(size, align, goal,
					    BOOTMEM_ALLOC_ACCESSIBLE, node);
}

static void *vmemmap_buf;
static void *vmemmap_buf_end;

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;
		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));
}

/* need to make sure size is all the same during early stage */
void * __meminit vmemmap_alloc_block_buf(unsigned long size, int node)
{
	void *ptr;

	if (!vmemmap_buf)
		return vmemmap_alloc_block(size, node);

	/* take the from buf */
	ptr = (void *)ALIGN((unsigned long)vmemmap_buf, size);
	if (ptr + size > vmemmap_buf_end)
		return vmemmap_alloc_block(size, node);

	vmemmap_buf = ptr + size;

	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;
}

/**
 * vmem_altmap_alloc - allocate pages from the vmem_altmap reservation
 * @altmap - reserved page pool for the allocation
 * @nr_pfns - size (in pages) of the allocation
 *
 * Allocations are aligned to the size of the request
 */
static unsigned long __meminit vmem_altmap_alloc(struct vmem_altmap *altmap,
		unsigned long nr_pfns)
{
	unsigned long pfn = vmem_altmap_next_pfn(altmap);
	unsigned long nr_align;

	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 ULONG_MAX;
	altmap->alloc += nr_pfns;
	altmap->align += nr_align;
	return pfn + nr_align;
}

void * __meminit altmap_alloc_block_buf(unsigned long size,
		struct vmem_altmap *altmap)
{
	unsigned long pfn, nr_pfns;
	void *ptr;

	if (size & ~PAGE_MASK) {
		pr_warn_once("%s: allocations must be multiple of PAGE_SIZE (%ld)\n",
				__func__, size);
		return NULL;
	}

	nr_pfns = size >> PAGE_SHIFT;
	pfn = vmem_altmap_alloc(altmap, nr_pfns);
	if (pfn < ULONG_MAX)
		ptr = __va(__pfn_to_phys(pfn));
	else
		ptr = NULL;
	pr_debug("%s: pfn: %#lx alloc: %ld align: %ld nr: %#lx\n",
			__func__, pfn, altmap->alloc, altmap->align, nr_pfns);

	return ptr;
}

void __meminit vmemmap_verify(pte_t *pte, int node,
				unsigned long start, unsigned long end)
{
	unsigned long pfn = pte_pfn(*pte);
	int actual_node = early_pfn_to_nid(pfn);

	if (node_distance(actual_node, node) > LOCAL_DISTANCE)
		pr_warn("[%lx-%lx] potential offnode page_structs\n",
			start, end - 1);
}

pte_t * __meminit vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node)
{
	pte_t *pte = pte_offset_kernel(pmd, addr);
	if (pte_none(*pte)) {
		pte_t entry;
		void *p = vmemmap_alloc_block_buf(PAGE_SIZE, node);
		if (!p)
			return NULL;
		entry = pfn_pte(__pa(p) >> PAGE_SHIFT, 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;
		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;
		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;
		p4d_populate(&init_mm, 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(&init_mm, pgd, p);
	}
	return pgd;
}

int __meminit vmemmap_populate_basepages(unsigned long start,
					 unsigned long end, int node)
{
	unsigned long addr = start;
	pgd_t *pgd;
	p4d_t *p4d;
	pud_t *pud;
	pmd_t *pmd;
	pte_t *pte;

	for (; addr < end; addr += PAGE_SIZE) {
		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 = vmemmap_pmd_populate(pud, addr, node);
		if (!pmd)
			return -ENOMEM;
		pte = vmemmap_pte_populate(pmd, addr, node);
		if (!pte)
			return -ENOMEM;
		vmemmap_verify(pte, node, addr, addr + PAGE_SIZE);
	}

	return 0;
}

struct page * __meminit sparse_mem_map_populate(unsigned long pnum, int nid,
		struct vmem_altmap *altmap)
{
	unsigned long start;
	unsigned long end;
	struct page *map;

	map = pfn_to_page(pnum * PAGES_PER_SECTION);
	start = (unsigned long)map;
	end = (unsigned long)(map + PAGES_PER_SECTION);

	if (vmemmap_populate(start, end, nid, altmap))
		return NULL;

	return map;
}

void __init sparse_mem_maps_populate_node(struct page **map_map,
					  unsigned long pnum_begin,
					  unsigned long pnum_end,
					  unsigned long map_count, int nodeid)
{
	unsigned long pnum;
	unsigned long size = sizeof(struct page) * PAGES_PER_SECTION;
	void *vmemmap_buf_start;

	size = ALIGN(size, PMD_SIZE);
	vmemmap_buf_start = __earlyonly_bootmem_alloc(nodeid, size * map_count,
			 PMD_SIZE, __pa(MAX_DMA_ADDRESS));

	if (vmemmap_buf_start) {
		vmemmap_buf = vmemmap_buf_start;
		vmemmap_buf_end = vmemmap_buf_start + size * map_count;
	}

	for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
		struct mem_section *ms;

		if (!present_section_nr(pnum))
			continue;

		map_map[pnum] = sparse_mem_map_populate(pnum, nodeid, NULL);
		if (map_map[pnum])
			continue;
		ms = __nr_to_section(pnum);
		pr_err("%s: sparsemem memory map backing failed some memory will not be available\n",
		       __func__);
		ms->section_mem_map = 0;
	}

	if (vmemmap_buf_start) {
		/* need to free left buf */
		memblock_free_early(__pa(vmemmap_buf),
				    vmemmap_buf_end - vmemmap_buf);
		vmemmap_buf = NULL;
		vmemmap_buf_end = NULL;
	}
}
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
8f6aac41 CL	2	/*
	3	* Virtual Memory Map support
	4	*
cde53535	5	* (C) 2007 sgi. Christoph Lameter.
8f6aac41 CL	6	*
	7	* Virtual memory maps allow VM primitives pfn_to_page, page_to_pfn,
	8	* virt_to_page, page_address() to be implemented as a base offset
	9	* calculation without memory access.
	10	*
	11	* However, virtual mappings need a page table and TLBs. Many Linux
	12	* architectures already map their physical space using 1-1 mappings
b595076a	13	* via TLBs. For those arches the virtual memory map is essentially
8f6aac41 CL	14	* for free if we use the same page size as the 1-1 mappings. In that
	15	* case the overhead consists of a few additional pages that are
	16	* allocated to create a view of memory for vmemmap.
	17	*
29c71111 AW	18	* The architecture is expected to provide a vmemmap_populate() function
29c71111 AW	19	* to instantiate the mapping.
8f6aac41 CL	20	*/
	21	#include <linux/mm.h>
	22	#include <linux/mmzone.h>
	23	#include <linux/bootmem.h>
4b94ffdc	24	#include <linux/memremap.h>
8f6aac41	25	#include <linux/highmem.h>
5a0e3ad6	26	#include <linux/slab.h>
8f6aac41 CL	27	#include <linux/spinlock.h>
8f6aac41 CL	28	#include <linux/vmalloc.h>
8bca44bb	29	#include <linux/sched.h>
8f6aac41 CL	30	#include <asm/dma.h>
	31	#include <asm/pgalloc.h>
	32	#include <asm/pgtable.h>
	33
	34	/*
	35	* Allocate a block of memory to be used to back the virtual memory map
	36	* or to back the page tables that are used to create the mapping.
	37	* Uses the main allocators if they are available, else bootmem.
	38	*/
e0dc3a53	39
bd721ea7	40	static void * __ref __earlyonly_bootmem_alloc(int node,
e0dc3a53 KH	41	unsigned long size,
	42	unsigned long align,
	43	unsigned long goal)
	44	{
f7f99100	45	return memblock_virt_alloc_try_nid_raw(size, align, goal,
bb016b84	46	BOOTMEM_ALLOC_ACCESSIBLE, node);
e0dc3a53 KH	47	}
e0dc3a53 KH	48
9bdac914 YL	49	static void *vmemmap_buf;
9bdac914 YL	50	static void *vmemmap_buf_end;
e0dc3a53	51
8f6aac41 CL	52	void * __meminit vmemmap_alloc_block(unsigned long size, int node)
	53	{
	54	/* If the main allocator is up use that, fallback to bootmem. */
	55	if (slab_is_available()) {
fcdaf842 MH	56	gfp_t gfp_mask = GFP_KERNEL\|__GFP_RETRY_MAYFAIL\|__GFP_NOWARN;
	57	int order = get_order(size);
	58	static bool warned;
f52407ce SL	59	struct page *page;
f52407ce SL	60
fcdaf842	61	page = alloc_pages_node(node, gfp_mask, order);
8f6aac41 CL	62	if (page)
8f6aac41 CL	63	return page_address(page);
fcdaf842 MH	64
	65	if (!warned) {
	66	warn_alloc(gfp_mask & ~__GFP_NOWARN, NULL,
	67	"vmemmap alloc failure: order:%u", order);
	68	warned = true;
	69	}
8f6aac41 CL	70	return NULL;
8f6aac41 CL	71	} else
e0dc3a53	72	return __earlyonly_bootmem_alloc(node, size, size,
8f6aac41 CL	73	__pa(MAX_DMA_ADDRESS));
	74	}
	75
9bdac914	76	/* need to make sure size is all the same during early stage */
a8fc357b	77	void * __meminit vmemmap_alloc_block_buf(unsigned long size, int node)
9bdac914 YL	78	{
	79	void *ptr;
	80
	81	if (!vmemmap_buf)
	82	return vmemmap_alloc_block(size, node);
	83
	84	/* take the from buf */
	85	ptr = (void *)ALIGN((unsigned long)vmemmap_buf, size);
	86	if (ptr + size > vmemmap_buf_end)
	87	return vmemmap_alloc_block(size, node);
	88
	89	vmemmap_buf = ptr + size;
	90
	91	return ptr;
	92	}
	93
4b94ffdc DW	94	static unsigned long __meminit vmem_altmap_next_pfn(struct vmem_altmap *altmap)
	95	{
	96	return altmap->base_pfn + altmap->reserve + altmap->alloc
	97	+ altmap->align;
	98	}
	99
	100	static unsigned long __meminit vmem_altmap_nr_free(struct vmem_altmap *altmap)
	101	{
	102	unsigned long allocated = altmap->alloc + altmap->align;
	103
	104	if (altmap->free > allocated)
	105	return altmap->free - allocated;
	106	return 0;
	107	}
	108
	109	/**
	110	* vmem_altmap_alloc - allocate pages from the vmem_altmap reservation
	111	* @altmap - reserved page pool for the allocation
	112	* @nr_pfns - size (in pages) of the allocation
	113	*
	114	* Allocations are aligned to the size of the request
	115	*/
	116	static unsigned long __meminit vmem_altmap_alloc(struct vmem_altmap *altmap,
	117	unsigned long nr_pfns)
	118	{
	119	unsigned long pfn = vmem_altmap_next_pfn(altmap);
	120	unsigned long nr_align;
	121
	122	nr_align = 1UL << find_first_bit(&nr_pfns, BITS_PER_LONG);
	123	nr_align = ALIGN(pfn, nr_align) - pfn;
	124
	125	if (nr_pfns + nr_align > vmem_altmap_nr_free(altmap))
	126	return ULONG_MAX;
	127	altmap->alloc += nr_pfns;
	128	altmap->align += nr_align;
	129	return pfn + nr_align;
	130	}
	131
a8fc357b	132	void * __meminit altmap_alloc_block_buf(unsigned long size,
4b94ffdc DW	133	struct vmem_altmap *altmap)
	134	{
	135	unsigned long pfn, nr_pfns;
	136	void *ptr;
	137
	138	if (size & ~PAGE_MASK) {
	139	pr_warn_once("%s: allocations must be multiple of PAGE_SIZE (%ld)\n",
	140	__func__, size);
	141	return NULL;
	142	}
	143
	144	nr_pfns = size >> PAGE_SHIFT;
	145	pfn = vmem_altmap_alloc(altmap, nr_pfns);
	146	if (pfn < ULONG_MAX)
	147	ptr = __va(__pfn_to_phys(pfn));
	148	else
	149	ptr = NULL;
	150	pr_debug("%s: pfn: %#lx alloc: %ld align: %ld nr: %#lx\n",
	151	__func__, pfn, altmap->alloc, altmap->align, nr_pfns);
	152
	153	return ptr;
	154	}
	155
8f6aac41 CL	156	void __meminit vmemmap_verify(pte_t *pte, int node,
	157	unsigned long start, unsigned long end)
	158	{
	159	unsigned long pfn = pte_pfn(*pte);
	160	int actual_node = early_pfn_to_nid(pfn);
	161
b41ad14c	162	if (node_distance(actual_node, node) > LOCAL_DISTANCE)
1170532b JP	163	pr_warn("[%lx-%lx] potential offnode page_structs\n",
1170532b JP	164	start, end - 1);
8f6aac41 CL	165	}
8f6aac41 CL	166
29c71111	167	pte_t * __meminit vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node)
8f6aac41	168	{
29c71111 AW	169	pte_t *pte = pte_offset_kernel(pmd, addr);
	170	if (pte_none(*pte)) {
	171	pte_t entry;
a8fc357b	172	void *p = vmemmap_alloc_block_buf(PAGE_SIZE, node);
29c71111	173	if (!p)
9dce07f1	174	return NULL;
29c71111 AW	175	entry = pfn_pte(__pa(p) >> PAGE_SHIFT, PAGE_KERNEL);
	176	set_pte_at(&init_mm, addr, pte, entry);
	177	}
	178	return pte;
8f6aac41 CL	179	}
8f6aac41 CL	180
f7f99100 PT	181	static void * __meminit vmemmap_alloc_block_zero(unsigned long size, int node)
	182	{
	183	void *p = vmemmap_alloc_block(size, node);
	184
	185	if (!p)
	186	return NULL;
	187	memset(p, 0, size);
	188
	189	return p;
	190	}
	191
29c71111	192	pmd_t * __meminit vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node)
8f6aac41	193	{
29c71111 AW	194	pmd_t *pmd = pmd_offset(pud, addr);
29c71111 AW	195	if (pmd_none(*pmd)) {
f7f99100	196	void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
29c71111	197	if (!p)
9dce07f1	198	return NULL;
29c71111	199	pmd_populate_kernel(&init_mm, pmd, p);
8f6aac41	200	}
29c71111	201	return pmd;
8f6aac41	202	}
8f6aac41	203
c2febafc	204	pud_t * __meminit vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node)
8f6aac41	205	{
c2febafc	206	pud_t *pud = pud_offset(p4d, addr);
29c71111	207	if (pud_none(*pud)) {
f7f99100	208	void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
29c71111	209	if (!p)
9dce07f1	210	return NULL;
29c71111 AW	211	pud_populate(&init_mm, pud, p);
	212	}
	213	return pud;
	214	}
8f6aac41	215
c2febafc KS	216	p4d_t * __meminit vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node)
	217	{
	218	p4d_t *p4d = p4d_offset(pgd, addr);
	219	if (p4d_none(*p4d)) {
f7f99100	220	void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
c2febafc KS	221	if (!p)
	222	return NULL;
	223	p4d_populate(&init_mm, p4d, p);
	224	}
	225	return p4d;
	226	}
	227
29c71111 AW	228	pgd_t * __meminit vmemmap_pgd_populate(unsigned long addr, int node)
	229	{
	230	pgd_t *pgd = pgd_offset_k(addr);
	231	if (pgd_none(*pgd)) {
f7f99100	232	void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
29c71111	233	if (!p)
9dce07f1	234	return NULL;
29c71111	235	pgd_populate(&init_mm, pgd, p);
8f6aac41	236	}
29c71111	237	return pgd;
8f6aac41 CL	238	}
8f6aac41 CL	239
0aad818b JW	240	int __meminit vmemmap_populate_basepages(unsigned long start,
0aad818b JW	241	unsigned long end, int node)
8f6aac41	242	{
0aad818b	243	unsigned long addr = start;
29c71111	244	pgd_t *pgd;
c2febafc	245	p4d_t *p4d;
29c71111 AW	246	pud_t *pud;
	247	pmd_t *pmd;
	248	pte_t *pte;
8f6aac41	249
29c71111 AW	250	for (; addr < end; addr += PAGE_SIZE) {
	251	pgd = vmemmap_pgd_populate(addr, node);
	252	if (!pgd)
	253	return -ENOMEM;
c2febafc KS	254	p4d = vmemmap_p4d_populate(pgd, addr, node);
	255	if (!p4d)
	256	return -ENOMEM;
	257	pud = vmemmap_pud_populate(p4d, addr, node);
29c71111 AW	258	if (!pud)
	259	return -ENOMEM;
	260	pmd = vmemmap_pmd_populate(pud, addr, node);
	261	if (!pmd)
	262	return -ENOMEM;
	263	pte = vmemmap_pte_populate(pmd, addr, node);
	264	if (!pte)
	265	return -ENOMEM;
	266	vmemmap_verify(pte, node, addr, addr + PAGE_SIZE);
8f6aac41	267	}
29c71111 AW	268
29c71111 AW	269	return 0;
8f6aac41	270	}
8f6aac41	271
7b73d978 CH	272	struct page * __meminit sparse_mem_map_populate(unsigned long pnum, int nid,
7b73d978 CH	273	struct vmem_altmap *altmap)
8f6aac41	274	{
0aad818b JW	275	unsigned long start;
	276	unsigned long end;
	277	struct page *map;
	278
	279	map = pfn_to_page(pnum * PAGES_PER_SECTION);
	280	start = (unsigned long)map;
	281	end = (unsigned long)(map + PAGES_PER_SECTION);
	282
7b73d978	283	if (vmemmap_populate(start, end, nid, altmap))
8f6aac41 CL	284	return NULL;
	285
	286	return map;
	287	}
9bdac914 YL	288
	289	void __init sparse_mem_maps_populate_node(struct page **map_map,
	290	unsigned long pnum_begin,
	291	unsigned long pnum_end,
	292	unsigned long map_count, int nodeid)
	293	{
	294	unsigned long pnum;
	295	unsigned long size = sizeof(struct page) * PAGES_PER_SECTION;
	296	void *vmemmap_buf_start;
	297
	298	size = ALIGN(size, PMD_SIZE);
	299	vmemmap_buf_start = __earlyonly_bootmem_alloc(nodeid, size * map_count,
	300	PMD_SIZE, __pa(MAX_DMA_ADDRESS));
	301
	302	if (vmemmap_buf_start) {
	303	vmemmap_buf = vmemmap_buf_start;
	304	vmemmap_buf_end = vmemmap_buf_start + size * map_count;
	305	}
	306
	307	for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
	308	struct mem_section *ms;
	309
	310	if (!present_section_nr(pnum))
	311	continue;
	312
7b73d978	313	map_map[pnum] = sparse_mem_map_populate(pnum, nodeid, NULL);
9bdac914 YL	314	if (map_map[pnum])
	315	continue;
	316	ms = __nr_to_section(pnum);
1170532b	317	pr_err("%s: sparsemem memory map backing failed some memory will not be available\n",
756a025f	318	__func__);
9bdac914 YL	319	ms->section_mem_map = 0;
	320	}
	321
	322	if (vmemmap_buf_start) {
	323	/* need to free left buf */
bb016b84 SS	324	memblock_free_early(__pa(vmemmap_buf),
bb016b84 SS	325	vmemmap_buf_end - vmemmap_buf);
9bdac914 YL	326	vmemmap_buf = NULL;
	327	vmemmap_buf_end = NULL;
	328	}
	329	}