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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Virtual Memory Map support
4 *
5 * (C) 2007 sgi. Christoph Lameter.
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
13 * via TLBs. For those arches the virtual memory map is essentially
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 *
18 * The architecture is expected to provide a vmemmap_populate() function
19 * to instantiate the mapping.
20 */
21#include <linux/mm.h>
22#include <linux/mmzone.h>
23#include <linux/bootmem.h>
24#include <linux/memremap.h>
25#include <linux/highmem.h>
26#include <linux/slab.h>
27#include <linux/spinlock.h>
28#include <linux/vmalloc.h>
29#include <linux/sched.h>
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 */
39
40static void * __ref __earlyonly_bootmem_alloc(int node,
41 unsigned long size,
42 unsigned long align,
43 unsigned long goal)
44{
45 return memblock_virt_alloc_try_nid_raw(size, align, goal,
46 BOOTMEM_ALLOC_ACCESSIBLE, node);
47}
48
49static void *vmemmap_buf;
50static void *vmemmap_buf_end;
51
52void * __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()) {
56 gfp_t gfp_mask = GFP_KERNEL|__GFP_RETRY_MAYFAIL|__GFP_NOWARN;
57 int order = get_order(size);
58 static bool warned;
59 struct page *page;
60
61 page = alloc_pages_node(node, gfp_mask, order);
62 if (page)
63 return page_address(page);
64
65 if (!warned) {
66 warn_alloc(gfp_mask & ~__GFP_NOWARN, NULL,
67 "vmemmap alloc failure: order:%u", order);
68 warned = true;
69 }
70 return NULL;
71 } else
72 return __earlyonly_bootmem_alloc(node, size, size,
73 __pa(MAX_DMA_ADDRESS));
74}
75
76/* need to make sure size is all the same during early stage */
77void * __meminit vmemmap_alloc_block_buf(unsigned long size, int node)
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
94static 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
100static 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 * altmap_alloc_block_buf - allocate pages from the device page map
111 * @altmap: device page map
112 * @size: size (in bytes) of the allocation
113 *
114 * Allocations are aligned to the size of the request.
115 */
116void * __meminit altmap_alloc_block_buf(unsigned long size,
117 struct vmem_altmap *altmap)
118{
119 unsigned long pfn, nr_pfns, nr_align;
120
121 if (size & ~PAGE_MASK) {
122 pr_warn_once("%s: allocations must be multiple of PAGE_SIZE (%ld)\n",
123 __func__, size);
124 return NULL;
125 }
126
127 pfn = vmem_altmap_next_pfn(altmap);
128 nr_pfns = size >> PAGE_SHIFT;
129 nr_align = 1UL << find_first_bit(&nr_pfns, BITS_PER_LONG);
130 nr_align = ALIGN(pfn, nr_align) - pfn;
131 if (nr_pfns + nr_align > vmem_altmap_nr_free(altmap))
132 return NULL;
133
134 altmap->alloc += nr_pfns;
135 altmap->align += nr_align;
136 pfn += nr_align;
137
138 pr_debug("%s: pfn: %#lx alloc: %ld align: %ld nr: %#lx\n",
139 __func__, pfn, altmap->alloc, altmap->align, nr_pfns);
140 return __va(__pfn_to_phys(pfn));
141}
142
143void __meminit vmemmap_verify(pte_t *pte, int node,
144 unsigned long start, unsigned long end)
145{
146 unsigned long pfn = pte_pfn(*pte);
147 int actual_node = early_pfn_to_nid(pfn);
148
149 if (node_distance(actual_node, node) > LOCAL_DISTANCE)
150 pr_warn("[%lx-%lx] potential offnode page_structs\n",
151 start, end - 1);
152}
153
154pte_t * __meminit vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node)
155{
156 pte_t *pte = pte_offset_kernel(pmd, addr);
157 if (pte_none(*pte)) {
158 pte_t entry;
159 void *p = vmemmap_alloc_block_buf(PAGE_SIZE, node);
160 if (!p)
161 return NULL;
162 entry = pfn_pte(__pa(p) >> PAGE_SHIFT, PAGE_KERNEL);
163 set_pte_at(&init_mm, addr, pte, entry);
164 }
165 return pte;
166}
167
168static void * __meminit vmemmap_alloc_block_zero(unsigned long size, int node)
169{
170 void *p = vmemmap_alloc_block(size, node);
171
172 if (!p)
173 return NULL;
174 memset(p, 0, size);
175
176 return p;
177}
178
179pmd_t * __meminit vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node)
180{
181 pmd_t *pmd = pmd_offset(pud, addr);
182 if (pmd_none(*pmd)) {
183 void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
184 if (!p)
185 return NULL;
186 pmd_populate_kernel(&init_mm, pmd, p);
187 }
188 return pmd;
189}
190
191pud_t * __meminit vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node)
192{
193 pud_t *pud = pud_offset(p4d, addr);
194 if (pud_none(*pud)) {
195 void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
196 if (!p)
197 return NULL;
198 pud_populate(&init_mm, pud, p);
199 }
200 return pud;
201}
202
203p4d_t * __meminit vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node)
204{
205 p4d_t *p4d = p4d_offset(pgd, addr);
206 if (p4d_none(*p4d)) {
207 void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
208 if (!p)
209 return NULL;
210 p4d_populate(&init_mm, p4d, p);
211 }
212 return p4d;
213}
214
215pgd_t * __meminit vmemmap_pgd_populate(unsigned long addr, int node)
216{
217 pgd_t *pgd = pgd_offset_k(addr);
218 if (pgd_none(*pgd)) {
219 void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
220 if (!p)
221 return NULL;
222 pgd_populate(&init_mm, pgd, p);
223 }
224 return pgd;
225}
226
227int __meminit vmemmap_populate_basepages(unsigned long start,
228 unsigned long end, int node)
229{
230 unsigned long addr = start;
231 pgd_t *pgd;
232 p4d_t *p4d;
233 pud_t *pud;
234 pmd_t *pmd;
235 pte_t *pte;
236
237 for (; addr < end; addr += PAGE_SIZE) {
238 pgd = vmemmap_pgd_populate(addr, node);
239 if (!pgd)
240 return -ENOMEM;
241 p4d = vmemmap_p4d_populate(pgd, addr, node);
242 if (!p4d)
243 return -ENOMEM;
244 pud = vmemmap_pud_populate(p4d, addr, node);
245 if (!pud)
246 return -ENOMEM;
247 pmd = vmemmap_pmd_populate(pud, addr, node);
248 if (!pmd)
249 return -ENOMEM;
250 pte = vmemmap_pte_populate(pmd, addr, node);
251 if (!pte)
252 return -ENOMEM;
253 vmemmap_verify(pte, node, addr, addr + PAGE_SIZE);
254 }
255
256 return 0;
257}
258
259struct page * __meminit sparse_mem_map_populate(unsigned long pnum, int nid,
260 struct vmem_altmap *altmap)
261{
262 unsigned long start;
263 unsigned long end;
264 struct page *map;
265
266 map = pfn_to_page(pnum * PAGES_PER_SECTION);
267 start = (unsigned long)map;
268 end = (unsigned long)(map + PAGES_PER_SECTION);
269
270 if (vmemmap_populate(start, end, nid, altmap))
271 return NULL;
272
273 return map;
274}
275
276void __init sparse_mem_maps_populate_node(struct page **map_map,
277 unsigned long pnum_begin,
278 unsigned long pnum_end,
279 unsigned long map_count, int nodeid)
280{
281 unsigned long pnum;
282 unsigned long size = sizeof(struct page) * PAGES_PER_SECTION;
283 void *vmemmap_buf_start;
284
285 size = ALIGN(size, PMD_SIZE);
286 vmemmap_buf_start = __earlyonly_bootmem_alloc(nodeid, size * map_count,
287 PMD_SIZE, __pa(MAX_DMA_ADDRESS));
288
289 if (vmemmap_buf_start) {
290 vmemmap_buf = vmemmap_buf_start;
291 vmemmap_buf_end = vmemmap_buf_start + size * map_count;
292 }
293
294 for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
295 struct mem_section *ms;
296
297 if (!present_section_nr(pnum))
298 continue;
299
300 map_map[pnum] = sparse_mem_map_populate(pnum, nodeid, NULL);
301 if (map_map[pnum])
302 continue;
303 ms = __nr_to_section(pnum);
304 pr_err("%s: sparsemem memory map backing failed some memory will not be available\n",
305 __func__);
306 ms->section_mem_map = 0;
307 }
308
309 if (vmemmap_buf_start) {
310 /* need to free left buf */
311 memblock_free_early(__pa(vmemmap_buf),
312 vmemmap_buf_end - vmemmap_buf);
313 vmemmap_buf = NULL;
314 vmemmap_buf_end = NULL;
315 }
316}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Virtual Memory Map support
4 *
5 * (C) 2007 sgi. Christoph Lameter.
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
13 * via TLBs. For those arches the virtual memory map is essentially
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 *
18 * The architecture is expected to provide a vmemmap_populate() function
19 * to instantiate the mapping.
20 */
21#include <linux/mm.h>
22#include <linux/mmzone.h>
23#include <linux/memblock.h>
24#include <linux/memremap.h>
25#include <linux/highmem.h>
26#include <linux/slab.h>
27#include <linux/spinlock.h>
28#include <linux/vmalloc.h>
29#include <linux/sched.h>
30#include <linux/pgtable.h>
31#include <linux/bootmem_info.h>
32
33#include <asm/dma.h>
34#include <asm/pgalloc.h>
35#include <asm/tlbflush.h>
36
37/**
38 * struct vmemmap_remap_walk - walk vmemmap page table
39 *
40 * @remap_pte: called for each lowest-level entry (PTE).
41 * @nr_walked: the number of walked pte.
42 * @reuse_page: the page which is reused for the tail vmemmap pages.
43 * @reuse_addr: the virtual address of the @reuse_page page.
44 * @vmemmap_pages: the list head of the vmemmap pages that can be freed
45 * or is mapped from.
46 */
47struct vmemmap_remap_walk {
48 void (*remap_pte)(pte_t *pte, unsigned long addr,
49 struct vmemmap_remap_walk *walk);
50 unsigned long nr_walked;
51 struct page *reuse_page;
52 unsigned long reuse_addr;
53 struct list_head *vmemmap_pages;
54};
55
56static int split_vmemmap_huge_pmd(pmd_t *pmd, unsigned long start,
57 struct vmemmap_remap_walk *walk)
58{
59 pmd_t __pmd;
60 int i;
61 unsigned long addr = start;
62 struct page *page = pmd_page(*pmd);
63 pte_t *pgtable = pte_alloc_one_kernel(&init_mm);
64
65 if (!pgtable)
66 return -ENOMEM;
67
68 pmd_populate_kernel(&init_mm, &__pmd, pgtable);
69
70 for (i = 0; i < PMD_SIZE / PAGE_SIZE; i++, addr += PAGE_SIZE) {
71 pte_t entry, *pte;
72 pgprot_t pgprot = PAGE_KERNEL;
73
74 entry = mk_pte(page + i, pgprot);
75 pte = pte_offset_kernel(&__pmd, addr);
76 set_pte_at(&init_mm, addr, pte, entry);
77 }
78
79 /* Make pte visible before pmd. See comment in __pte_alloc(). */
80 smp_wmb();
81 pmd_populate_kernel(&init_mm, pmd, pgtable);
82
83 flush_tlb_kernel_range(start, start + PMD_SIZE);
84
85 return 0;
86}
87
88static void vmemmap_pte_range(pmd_t *pmd, unsigned long addr,
89 unsigned long end,
90 struct vmemmap_remap_walk *walk)
91{
92 pte_t *pte = pte_offset_kernel(pmd, addr);
93
94 /*
95 * The reuse_page is found 'first' in table walk before we start
96 * remapping (which is calling @walk->remap_pte).
97 */
98 if (!walk->reuse_page) {
99 walk->reuse_page = pte_page(*pte);
100 /*
101 * Because the reuse address is part of the range that we are
102 * walking, skip the reuse address range.
103 */
104 addr += PAGE_SIZE;
105 pte++;
106 walk->nr_walked++;
107 }
108
109 for (; addr != end; addr += PAGE_SIZE, pte++) {
110 walk->remap_pte(pte, addr, walk);
111 walk->nr_walked++;
112 }
113}
114
115static int vmemmap_pmd_range(pud_t *pud, unsigned long addr,
116 unsigned long end,
117 struct vmemmap_remap_walk *walk)
118{
119 pmd_t *pmd;
120 unsigned long next;
121
122 pmd = pmd_offset(pud, addr);
123 do {
124 if (pmd_leaf(*pmd)) {
125 int ret;
126
127 ret = split_vmemmap_huge_pmd(pmd, addr & PMD_MASK, walk);
128 if (ret)
129 return ret;
130 }
131 next = pmd_addr_end(addr, end);
132 vmemmap_pte_range(pmd, addr, next, walk);
133 } while (pmd++, addr = next, addr != end);
134
135 return 0;
136}
137
138static int vmemmap_pud_range(p4d_t *p4d, unsigned long addr,
139 unsigned long end,
140 struct vmemmap_remap_walk *walk)
141{
142 pud_t *pud;
143 unsigned long next;
144
145 pud = pud_offset(p4d, addr);
146 do {
147 int ret;
148
149 next = pud_addr_end(addr, end);
150 ret = vmemmap_pmd_range(pud, addr, next, walk);
151 if (ret)
152 return ret;
153 } while (pud++, addr = next, addr != end);
154
155 return 0;
156}
157
158static int vmemmap_p4d_range(pgd_t *pgd, unsigned long addr,
159 unsigned long end,
160 struct vmemmap_remap_walk *walk)
161{
162 p4d_t *p4d;
163 unsigned long next;
164
165 p4d = p4d_offset(pgd, addr);
166 do {
167 int ret;
168
169 next = p4d_addr_end(addr, end);
170 ret = vmemmap_pud_range(p4d, addr, next, walk);
171 if (ret)
172 return ret;
173 } while (p4d++, addr = next, addr != end);
174
175 return 0;
176}
177
178static int vmemmap_remap_range(unsigned long start, unsigned long end,
179 struct vmemmap_remap_walk *walk)
180{
181 unsigned long addr = start;
182 unsigned long next;
183 pgd_t *pgd;
184
185 VM_BUG_ON(!IS_ALIGNED(start, PAGE_SIZE));
186 VM_BUG_ON(!IS_ALIGNED(end, PAGE_SIZE));
187
188 pgd = pgd_offset_k(addr);
189 do {
190 int ret;
191
192 next = pgd_addr_end(addr, end);
193 ret = vmemmap_p4d_range(pgd, addr, next, walk);
194 if (ret)
195 return ret;
196 } while (pgd++, addr = next, addr != end);
197
198 /*
199 * We only change the mapping of the vmemmap virtual address range
200 * [@start + PAGE_SIZE, end), so we only need to flush the TLB which
201 * belongs to the range.
202 */
203 flush_tlb_kernel_range(start + PAGE_SIZE, end);
204
205 return 0;
206}
207
208/*
209 * Free a vmemmap page. A vmemmap page can be allocated from the memblock
210 * allocator or buddy allocator. If the PG_reserved flag is set, it means
211 * that it allocated from the memblock allocator, just free it via the
212 * free_bootmem_page(). Otherwise, use __free_page().
213 */
214static inline void free_vmemmap_page(struct page *page)
215{
216 if (PageReserved(page))
217 free_bootmem_page(page);
218 else
219 __free_page(page);
220}
221
222/* Free a list of the vmemmap pages */
223static void free_vmemmap_page_list(struct list_head *list)
224{
225 struct page *page, *next;
226
227 list_for_each_entry_safe(page, next, list, lru) {
228 list_del(&page->lru);
229 free_vmemmap_page(page);
230 }
231}
232
233static void vmemmap_remap_pte(pte_t *pte, unsigned long addr,
234 struct vmemmap_remap_walk *walk)
235{
236 /*
237 * Remap the tail pages as read-only to catch illegal write operation
238 * to the tail pages.
239 */
240 pgprot_t pgprot = PAGE_KERNEL_RO;
241 pte_t entry = mk_pte(walk->reuse_page, pgprot);
242 struct page *page = pte_page(*pte);
243
244 list_add_tail(&page->lru, walk->vmemmap_pages);
245 set_pte_at(&init_mm, addr, pte, entry);
246}
247
248static void vmemmap_restore_pte(pte_t *pte, unsigned long addr,
249 struct vmemmap_remap_walk *walk)
250{
251 pgprot_t pgprot = PAGE_KERNEL;
252 struct page *page;
253 void *to;
254
255 BUG_ON(pte_page(*pte) != walk->reuse_page);
256
257 page = list_first_entry(walk->vmemmap_pages, struct page, lru);
258 list_del(&page->lru);
259 to = page_to_virt(page);
260 copy_page(to, (void *)walk->reuse_addr);
261
262 set_pte_at(&init_mm, addr, pte, mk_pte(page, pgprot));
263}
264
265/**
266 * vmemmap_remap_free - remap the vmemmap virtual address range [@start, @end)
267 * to the page which @reuse is mapped to, then free vmemmap
268 * which the range are mapped to.
269 * @start: start address of the vmemmap virtual address range that we want
270 * to remap.
271 * @end: end address of the vmemmap virtual address range that we want to
272 * remap.
273 * @reuse: reuse address.
274 *
275 * Return: %0 on success, negative error code otherwise.
276 */
277int vmemmap_remap_free(unsigned long start, unsigned long end,
278 unsigned long reuse)
279{
280 int ret;
281 LIST_HEAD(vmemmap_pages);
282 struct vmemmap_remap_walk walk = {
283 .remap_pte = vmemmap_remap_pte,
284 .reuse_addr = reuse,
285 .vmemmap_pages = &vmemmap_pages,
286 };
287
288 /*
289 * In order to make remapping routine most efficient for the huge pages,
290 * the routine of vmemmap page table walking has the following rules
291 * (see more details from the vmemmap_pte_range()):
292 *
293 * - The range [@start, @end) and the range [@reuse, @reuse + PAGE_SIZE)
294 * should be continuous.
295 * - The @reuse address is part of the range [@reuse, @end) that we are
296 * walking which is passed to vmemmap_remap_range().
297 * - The @reuse address is the first in the complete range.
298 *
299 * So we need to make sure that @start and @reuse meet the above rules.
300 */
301 BUG_ON(start - reuse != PAGE_SIZE);
302
303 mmap_write_lock(&init_mm);
304 ret = vmemmap_remap_range(reuse, end, &walk);
305 mmap_write_downgrade(&init_mm);
306
307 if (ret && walk.nr_walked) {
308 end = reuse + walk.nr_walked * PAGE_SIZE;
309 /*
310 * vmemmap_pages contains pages from the previous
311 * vmemmap_remap_range call which failed. These
312 * are pages which were removed from the vmemmap.
313 * They will be restored in the following call.
314 */
315 walk = (struct vmemmap_remap_walk) {
316 .remap_pte = vmemmap_restore_pte,
317 .reuse_addr = reuse,
318 .vmemmap_pages = &vmemmap_pages,
319 };
320
321 vmemmap_remap_range(reuse, end, &walk);
322 }
323 mmap_read_unlock(&init_mm);
324
325 free_vmemmap_page_list(&vmemmap_pages);
326
327 return ret;
328}
329
330static int alloc_vmemmap_page_list(unsigned long start, unsigned long end,
331 gfp_t gfp_mask, struct list_head *list)
332{
333 unsigned long nr_pages = (end - start) >> PAGE_SHIFT;
334 int nid = page_to_nid((struct page *)start);
335 struct page *page, *next;
336
337 while (nr_pages--) {
338 page = alloc_pages_node(nid, gfp_mask, 0);
339 if (!page)
340 goto out;
341 list_add_tail(&page->lru, list);
342 }
343
344 return 0;
345out:
346 list_for_each_entry_safe(page, next, list, lru)
347 __free_pages(page, 0);
348 return -ENOMEM;
349}
350
351/**
352 * vmemmap_remap_alloc - remap the vmemmap virtual address range [@start, end)
353 * to the page which is from the @vmemmap_pages
354 * respectively.
355 * @start: start address of the vmemmap virtual address range that we want
356 * to remap.
357 * @end: end address of the vmemmap virtual address range that we want to
358 * remap.
359 * @reuse: reuse address.
360 * @gfp_mask: GFP flag for allocating vmemmap pages.
361 *
362 * Return: %0 on success, negative error code otherwise.
363 */
364int vmemmap_remap_alloc(unsigned long start, unsigned long end,
365 unsigned long reuse, gfp_t gfp_mask)
366{
367 LIST_HEAD(vmemmap_pages);
368 struct vmemmap_remap_walk walk = {
369 .remap_pte = vmemmap_restore_pte,
370 .reuse_addr = reuse,
371 .vmemmap_pages = &vmemmap_pages,
372 };
373
374 /* See the comment in the vmemmap_remap_free(). */
375 BUG_ON(start - reuse != PAGE_SIZE);
376
377 if (alloc_vmemmap_page_list(start, end, gfp_mask, &vmemmap_pages))
378 return -ENOMEM;
379
380 mmap_read_lock(&init_mm);
381 vmemmap_remap_range(reuse, end, &walk);
382 mmap_read_unlock(&init_mm);
383
384 return 0;
385}
386
387/*
388 * Allocate a block of memory to be used to back the virtual memory map
389 * or to back the page tables that are used to create the mapping.
390 * Uses the main allocators if they are available, else bootmem.
391 */
392
393static void * __ref __earlyonly_bootmem_alloc(int node,
394 unsigned long size,
395 unsigned long align,
396 unsigned long goal)
397{
398 return memblock_alloc_try_nid_raw(size, align, goal,
399 MEMBLOCK_ALLOC_ACCESSIBLE, node);
400}
401
402void * __meminit vmemmap_alloc_block(unsigned long size, int node)
403{
404 /* If the main allocator is up use that, fallback to bootmem. */
405 if (slab_is_available()) {
406 gfp_t gfp_mask = GFP_KERNEL|__GFP_RETRY_MAYFAIL|__GFP_NOWARN;
407 int order = get_order(size);
408 static bool warned;
409 struct page *page;
410
411 page = alloc_pages_node(node, gfp_mask, order);
412 if (page)
413 return page_address(page);
414
415 if (!warned) {
416 warn_alloc(gfp_mask & ~__GFP_NOWARN, NULL,
417 "vmemmap alloc failure: order:%u", order);
418 warned = true;
419 }
420 return NULL;
421 } else
422 return __earlyonly_bootmem_alloc(node, size, size,
423 __pa(MAX_DMA_ADDRESS));
424}
425
426static void * __meminit altmap_alloc_block_buf(unsigned long size,
427 struct vmem_altmap *altmap);
428
429/* need to make sure size is all the same during early stage */
430void * __meminit vmemmap_alloc_block_buf(unsigned long size, int node,
431 struct vmem_altmap *altmap)
432{
433 void *ptr;
434
435 if (altmap)
436 return altmap_alloc_block_buf(size, altmap);
437
438 ptr = sparse_buffer_alloc(size);
439 if (!ptr)
440 ptr = vmemmap_alloc_block(size, node);
441 return ptr;
442}
443
444static unsigned long __meminit vmem_altmap_next_pfn(struct vmem_altmap *altmap)
445{
446 return altmap->base_pfn + altmap->reserve + altmap->alloc
447 + altmap->align;
448}
449
450static unsigned long __meminit vmem_altmap_nr_free(struct vmem_altmap *altmap)
451{
452 unsigned long allocated = altmap->alloc + altmap->align;
453
454 if (altmap->free > allocated)
455 return altmap->free - allocated;
456 return 0;
457}
458
459static void * __meminit altmap_alloc_block_buf(unsigned long size,
460 struct vmem_altmap *altmap)
461{
462 unsigned long pfn, nr_pfns, nr_align;
463
464 if (size & ~PAGE_MASK) {
465 pr_warn_once("%s: allocations must be multiple of PAGE_SIZE (%ld)\n",
466 __func__, size);
467 return NULL;
468 }
469
470 pfn = vmem_altmap_next_pfn(altmap);
471 nr_pfns = size >> PAGE_SHIFT;
472 nr_align = 1UL << find_first_bit(&nr_pfns, BITS_PER_LONG);
473 nr_align = ALIGN(pfn, nr_align) - pfn;
474 if (nr_pfns + nr_align > vmem_altmap_nr_free(altmap))
475 return NULL;
476
477 altmap->alloc += nr_pfns;
478 altmap->align += nr_align;
479 pfn += nr_align;
480
481 pr_debug("%s: pfn: %#lx alloc: %ld align: %ld nr: %#lx\n",
482 __func__, pfn, altmap->alloc, altmap->align, nr_pfns);
483 return __va(__pfn_to_phys(pfn));
484}
485
486void __meminit vmemmap_verify(pte_t *pte, int node,
487 unsigned long start, unsigned long end)
488{
489 unsigned long pfn = pte_pfn(*pte);
490 int actual_node = early_pfn_to_nid(pfn);
491
492 if (node_distance(actual_node, node) > LOCAL_DISTANCE)
493 pr_warn("[%lx-%lx] potential offnode page_structs\n",
494 start, end - 1);
495}
496
497pte_t * __meminit vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node,
498 struct vmem_altmap *altmap)
499{
500 pte_t *pte = pte_offset_kernel(pmd, addr);
501 if (pte_none(*pte)) {
502 pte_t entry;
503 void *p;
504
505 p = vmemmap_alloc_block_buf(PAGE_SIZE, node, altmap);
506 if (!p)
507 return NULL;
508 entry = pfn_pte(__pa(p) >> PAGE_SHIFT, PAGE_KERNEL);
509 set_pte_at(&init_mm, addr, pte, entry);
510 }
511 return pte;
512}
513
514static void * __meminit vmemmap_alloc_block_zero(unsigned long size, int node)
515{
516 void *p = vmemmap_alloc_block(size, node);
517
518 if (!p)
519 return NULL;
520 memset(p, 0, size);
521
522 return p;
523}
524
525pmd_t * __meminit vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node)
526{
527 pmd_t *pmd = pmd_offset(pud, addr);
528 if (pmd_none(*pmd)) {
529 void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
530 if (!p)
531 return NULL;
532 pmd_populate_kernel(&init_mm, pmd, p);
533 }
534 return pmd;
535}
536
537pud_t * __meminit vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node)
538{
539 pud_t *pud = pud_offset(p4d, addr);
540 if (pud_none(*pud)) {
541 void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
542 if (!p)
543 return NULL;
544 pud_populate(&init_mm, pud, p);
545 }
546 return pud;
547}
548
549p4d_t * __meminit vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node)
550{
551 p4d_t *p4d = p4d_offset(pgd, addr);
552 if (p4d_none(*p4d)) {
553 void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
554 if (!p)
555 return NULL;
556 p4d_populate(&init_mm, p4d, p);
557 }
558 return p4d;
559}
560
561pgd_t * __meminit vmemmap_pgd_populate(unsigned long addr, int node)
562{
563 pgd_t *pgd = pgd_offset_k(addr);
564 if (pgd_none(*pgd)) {
565 void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
566 if (!p)
567 return NULL;
568 pgd_populate(&init_mm, pgd, p);
569 }
570 return pgd;
571}
572
573int __meminit vmemmap_populate_basepages(unsigned long start, unsigned long end,
574 int node, struct vmem_altmap *altmap)
575{
576 unsigned long addr = start;
577 pgd_t *pgd;
578 p4d_t *p4d;
579 pud_t *pud;
580 pmd_t *pmd;
581 pte_t *pte;
582
583 for (; addr < end; addr += PAGE_SIZE) {
584 pgd = vmemmap_pgd_populate(addr, node);
585 if (!pgd)
586 return -ENOMEM;
587 p4d = vmemmap_p4d_populate(pgd, addr, node);
588 if (!p4d)
589 return -ENOMEM;
590 pud = vmemmap_pud_populate(p4d, addr, node);
591 if (!pud)
592 return -ENOMEM;
593 pmd = vmemmap_pmd_populate(pud, addr, node);
594 if (!pmd)
595 return -ENOMEM;
596 pte = vmemmap_pte_populate(pmd, addr, node, altmap);
597 if (!pte)
598 return -ENOMEM;
599 vmemmap_verify(pte, node, addr, addr + PAGE_SIZE);
600 }
601
602 return 0;
603}
604
605struct page * __meminit __populate_section_memmap(unsigned long pfn,
606 unsigned long nr_pages, int nid, struct vmem_altmap *altmap)
607{
608 unsigned long start = (unsigned long) pfn_to_page(pfn);
609 unsigned long end = start + nr_pages * sizeof(struct page);
610
611 if (WARN_ON_ONCE(!IS_ALIGNED(pfn, PAGES_PER_SUBSECTION) ||
612 !IS_ALIGNED(nr_pages, PAGES_PER_SUBSECTION)))
613 return NULL;
614
615 if (vmemmap_populate(start, end, nid, altmap))
616 return NULL;
617
618 return pfn_to_page(pfn);
619}