blob: 319b6f2fb8b9dc56300c082ab06a266673b091c9 [file] [log] [blame]
Tejun Heo5a0e3ad2010-03-24 17:04:11 +09001#include <linux/gfp.h>
Jaswinder Singh Rajput2c1b2842009-04-11 00:03:10 +05302#include <linux/initrd.h>
Pekka Enberg540aca02009-03-04 11:46:40 +02003#include <linux/ioport.h>
Pekka Enberge5b2bb52009-03-03 13:15:06 +02004#include <linux/swap.h>
Yinghai Lua9ce6bc2010-08-25 13:39:17 -07005#include <linux/memblock.h>
Pekka Enberg17623912011-11-01 15:58:22 +02006#include <linux/bootmem.h> /* for max_low_pfn */
Pekka Enberg540aca02009-03-04 11:46:40 +02007
Pekka Enberge5b2bb52009-03-03 13:15:06 +02008#include <asm/cacheflush.h>
Pekka Enbergf7650902009-03-05 14:55:05 +02009#include <asm/e820.h>
Pekka Enberg4fcb2082009-03-05 14:55:08 +020010#include <asm/init.h>
Pekka Enberge5b2bb52009-03-03 13:15:06 +020011#include <asm/page.h>
Pekka Enberg540aca02009-03-04 11:46:40 +020012#include <asm/page_types.h>
Pekka Enberge5b2bb52009-03-03 13:15:06 +020013#include <asm/sections.h>
Jan Beulich49834392009-05-06 13:06:47 +010014#include <asm/setup.h>
Pekka Enbergf7650902009-03-05 14:55:05 +020015#include <asm/tlbflush.h>
Pekka Enberg9518e0e2009-04-28 16:00:50 +030016#include <asm/tlb.h>
Jaswinder Singh Rajput76c06922009-07-01 19:54:23 +053017#include <asm/proto.h>
Pekka Enberg17623912011-11-01 15:58:22 +020018#include <asm/dma.h> /* for MAX_DMA_PFN */
Pekka Enberg9518e0e2009-04-28 16:00:50 +030019
Yinghai Lud1b19422011-02-24 14:46:24 +010020unsigned long __initdata pgt_buf_start;
21unsigned long __meminitdata pgt_buf_end;
22unsigned long __meminitdata pgt_buf_top;
Pekka Enbergf7650902009-03-05 14:55:05 +020023
24int after_bootmem;
25
26int direct_gbpages
27#ifdef CONFIG_DIRECT_GBPAGES
28 = 1
29#endif
30;
31
WANG Cong722bc6b2012-03-05 15:05:13 -080032struct map_range {
33 unsigned long start;
34 unsigned long end;
35 unsigned page_size_mask;
36};
37
38static void __init find_early_table_space(struct map_range *mr, unsigned long end,
39 int use_pse, int use_gbpages)
Pekka Enbergf7650902009-03-05 14:55:05 +020040{
Yinghai Lu4b239f42010-12-17 16:58:28 -080041 unsigned long puds, pmds, ptes, tables, start = 0, good_end = end;
Yinghai Lua9ce6bc2010-08-25 13:39:17 -070042 phys_addr_t base;
Pekka Enbergf7650902009-03-05 14:55:05 +020043
44 puds = (end + PUD_SIZE - 1) >> PUD_SHIFT;
45 tables = roundup(puds * sizeof(pud_t), PAGE_SIZE);
46
47 if (use_gbpages) {
48 unsigned long extra;
49
50 extra = end - ((end>>PUD_SHIFT) << PUD_SHIFT);
51 pmds = (extra + PMD_SIZE - 1) >> PMD_SHIFT;
52 } else
53 pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT;
54
55 tables += roundup(pmds * sizeof(pmd_t), PAGE_SIZE);
56
57 if (use_pse) {
58 unsigned long extra;
59
60 extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT);
61#ifdef CONFIG_X86_32
62 extra += PMD_SIZE;
63#endif
WANG Cong722bc6b2012-03-05 15:05:13 -080064 /* The first 2/4M doesn't use large pages. */
65 extra += mr->end - mr->start;
66
Pekka Enbergf7650902009-03-05 14:55:05 +020067 ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT;
68 } else
69 ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;
70
71 tables += roundup(ptes * sizeof(pte_t), PAGE_SIZE);
72
73#ifdef CONFIG_X86_32
74 /* for fixmap */
75 tables += roundup(__end_of_fixed_addresses * sizeof(pte_t), PAGE_SIZE);
Yinghai Lu80989ce2009-05-09 23:47:42 -070076#endif
Takashi Iwai8548c842011-10-23 23:19:12 +020077 good_end = max_pfn_mapped << PAGE_SHIFT;
Yinghai Lu1411e0e2010-12-27 16:48:17 -080078
Yinghai Lu4b239f42010-12-17 16:58:28 -080079 base = memblock_find_in_range(start, good_end, tables, PAGE_SIZE);
Tejun Heo1f5026a2011-07-12 09:58:09 +020080 if (!base)
Pekka Enbergf7650902009-03-05 14:55:05 +020081 panic("Cannot find space for the kernel page tables");
82
Yinghai Lud1b19422011-02-24 14:46:24 +010083 pgt_buf_start = base >> PAGE_SHIFT;
84 pgt_buf_end = pgt_buf_start;
85 pgt_buf_top = pgt_buf_start + (tables >> PAGE_SHIFT);
Pekka Enbergf7650902009-03-05 14:55:05 +020086
87 printk(KERN_DEBUG "kernel direct mapping tables up to %lx @ %lx-%lx\n",
Yinghai Lud1b19422011-02-24 14:46:24 +010088 end, pgt_buf_start << PAGE_SHIFT, pgt_buf_top << PAGE_SHIFT);
Pekka Enbergf7650902009-03-05 14:55:05 +020089}
90
Sedat Dilek53f80232011-04-17 16:17:34 +020091void __init native_pagetable_reserve(u64 start, u64 end)
Stefano Stabellini279b7062011-04-14 15:49:41 +010092{
Tejun Heo24aa0782011-07-12 11:16:06 +020093 memblock_reserve(start, end - start);
Stefano Stabellini279b7062011-04-14 15:49:41 +010094}
95
Pekka Enbergf7650902009-03-05 14:55:05 +020096#ifdef CONFIG_X86_32
97#define NR_RANGE_MR 3
98#else /* CONFIG_X86_64 */
99#define NR_RANGE_MR 5
100#endif
101
Jan Beulichdc9dd5c2009-03-12 12:40:06 +0000102static int __meminit save_mr(struct map_range *mr, int nr_range,
103 unsigned long start_pfn, unsigned long end_pfn,
104 unsigned long page_size_mask)
Pekka Enbergf7650902009-03-05 14:55:05 +0200105{
106 if (start_pfn < end_pfn) {
107 if (nr_range >= NR_RANGE_MR)
108 panic("run out of range for init_memory_mapping\n");
109 mr[nr_range].start = start_pfn<<PAGE_SHIFT;
110 mr[nr_range].end = end_pfn<<PAGE_SHIFT;
111 mr[nr_range].page_size_mask = page_size_mask;
112 nr_range++;
113 }
114
115 return nr_range;
116}
117
Pekka Enbergf7650902009-03-05 14:55:05 +0200118/*
119 * Setup the direct mapping of the physical memory at PAGE_OFFSET.
120 * This runs before bootmem is initialized and gets pages directly from
121 * the physical memory. To access them they are temporarily mapped.
122 */
123unsigned long __init_refok init_memory_mapping(unsigned long start,
124 unsigned long end)
125{
126 unsigned long page_size_mask = 0;
127 unsigned long start_pfn, end_pfn;
Pekka Enbergc77a3b52009-03-05 17:04:26 +0200128 unsigned long ret = 0;
Pekka Enbergf7650902009-03-05 14:55:05 +0200129 unsigned long pos;
Pekka Enbergf7650902009-03-05 14:55:05 +0200130
131 struct map_range mr[NR_RANGE_MR];
132 int nr_range, i;
133 int use_pse, use_gbpages;
134
135 printk(KERN_INFO "init_memory_mapping: %016lx-%016lx\n", start, end);
136
Vegard Nossumf8561292008-04-04 00:53:23 +0200137#if defined(CONFIG_DEBUG_PAGEALLOC) || defined(CONFIG_KMEMCHECK)
Pekka Enbergf7650902009-03-05 14:55:05 +0200138 /*
139 * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages.
140 * This will simplify cpa(), which otherwise needs to support splitting
141 * large pages into small in interrupt context, etc.
142 */
143 use_pse = use_gbpages = 0;
144#else
145 use_pse = cpu_has_pse;
146 use_gbpages = direct_gbpages;
147#endif
148
Pekka Enbergf7650902009-03-05 14:55:05 +0200149 /* Enable PSE if available */
150 if (cpu_has_pse)
151 set_in_cr4(X86_CR4_PSE);
152
153 /* Enable PGE if available */
154 if (cpu_has_pge) {
155 set_in_cr4(X86_CR4_PGE);
156 __supported_pte_mask |= _PAGE_GLOBAL;
157 }
Pekka Enbergf7650902009-03-05 14:55:05 +0200158
159 if (use_gbpages)
160 page_size_mask |= 1 << PG_LEVEL_1G;
161 if (use_pse)
162 page_size_mask |= 1 << PG_LEVEL_2M;
163
164 memset(mr, 0, sizeof(mr));
165 nr_range = 0;
166
167 /* head if not big page alignment ? */
168 start_pfn = start >> PAGE_SHIFT;
169 pos = start_pfn << PAGE_SHIFT;
170#ifdef CONFIG_X86_32
171 /*
172 * Don't use a large page for the first 2/4MB of memory
173 * because there are often fixed size MTRRs in there
174 * and overlapping MTRRs into large pages can cause
175 * slowdowns.
176 */
177 if (pos == 0)
178 end_pfn = 1<<(PMD_SHIFT - PAGE_SHIFT);
179 else
180 end_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
181 << (PMD_SHIFT - PAGE_SHIFT);
182#else /* CONFIG_X86_64 */
183 end_pfn = ((pos + (PMD_SIZE - 1)) >> PMD_SHIFT)
184 << (PMD_SHIFT - PAGE_SHIFT);
185#endif
186 if (end_pfn > (end >> PAGE_SHIFT))
187 end_pfn = end >> PAGE_SHIFT;
188 if (start_pfn < end_pfn) {
189 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
190 pos = end_pfn << PAGE_SHIFT;
191 }
192
193 /* big page (2M) range */
194 start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
195 << (PMD_SHIFT - PAGE_SHIFT);
196#ifdef CONFIG_X86_32
197 end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
198#else /* CONFIG_X86_64 */
199 end_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT)
200 << (PUD_SHIFT - PAGE_SHIFT);
201 if (end_pfn > ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT)))
202 end_pfn = ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT));
203#endif
204
205 if (start_pfn < end_pfn) {
206 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
207 page_size_mask & (1<<PG_LEVEL_2M));
208 pos = end_pfn << PAGE_SHIFT;
209 }
210
211#ifdef CONFIG_X86_64
212 /* big page (1G) range */
213 start_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT)
214 << (PUD_SHIFT - PAGE_SHIFT);
215 end_pfn = (end >> PUD_SHIFT) << (PUD_SHIFT - PAGE_SHIFT);
216 if (start_pfn < end_pfn) {
217 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
218 page_size_mask &
219 ((1<<PG_LEVEL_2M)|(1<<PG_LEVEL_1G)));
220 pos = end_pfn << PAGE_SHIFT;
221 }
222
223 /* tail is not big page (1G) alignment */
224 start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
225 << (PMD_SHIFT - PAGE_SHIFT);
226 end_pfn = (end >> PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
227 if (start_pfn < end_pfn) {
228 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
229 page_size_mask & (1<<PG_LEVEL_2M));
230 pos = end_pfn << PAGE_SHIFT;
231 }
232#endif
233
234 /* tail is not big page (2M) alignment */
235 start_pfn = pos>>PAGE_SHIFT;
236 end_pfn = end>>PAGE_SHIFT;
237 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
238
239 /* try to merge same page size and continuous */
240 for (i = 0; nr_range > 1 && i < nr_range - 1; i++) {
241 unsigned long old_start;
242 if (mr[i].end != mr[i+1].start ||
243 mr[i].page_size_mask != mr[i+1].page_size_mask)
244 continue;
245 /* move it */
246 old_start = mr[i].start;
247 memmove(&mr[i], &mr[i+1],
248 (nr_range - 1 - i) * sizeof(struct map_range));
249 mr[i--].start = old_start;
250 nr_range--;
251 }
252
253 for (i = 0; i < nr_range; i++)
254 printk(KERN_DEBUG " %010lx - %010lx page %s\n",
255 mr[i].start, mr[i].end,
256 (mr[i].page_size_mask & (1<<PG_LEVEL_1G))?"1G":(
257 (mr[i].page_size_mask & (1<<PG_LEVEL_2M))?"2M":"4k"));
258
259 /*
260 * Find space for the kernel direct mapping tables.
261 *
262 * Later we should allocate these tables in the local node of the
263 * memory mapped. Unfortunately this is done currently before the
264 * nodes are discovered.
265 */
266 if (!after_bootmem)
WANG Cong722bc6b2012-03-05 15:05:13 -0800267 find_early_table_space(&mr[0], end, use_pse, use_gbpages);
Pekka Enbergf7650902009-03-05 14:55:05 +0200268
Pekka Enbergf7650902009-03-05 14:55:05 +0200269 for (i = 0; i < nr_range; i++)
270 ret = kernel_physical_mapping_init(mr[i].start, mr[i].end,
271 mr[i].page_size_mask);
Pekka Enbergf7650902009-03-05 14:55:05 +0200272
273#ifdef CONFIG_X86_32
274 early_ioremap_page_table_range_init();
275
276 load_cr3(swapper_pg_dir);
277#endif
278
Pekka Enbergf7650902009-03-05 14:55:05 +0200279 __flush_tlb_all();
280
Stefano Stabellini279b7062011-04-14 15:49:41 +0100281 /*
282 * Reserve the kernel pagetable pages we used (pgt_buf_start -
283 * pgt_buf_end) and free the other ones (pgt_buf_end - pgt_buf_top)
284 * so that they can be reused for other purposes.
285 *
Tejun Heo24aa0782011-07-12 11:16:06 +0200286 * On native it just means calling memblock_reserve, on Xen it also
287 * means marking RW the pagetable pages that we allocated before
Stefano Stabellini279b7062011-04-14 15:49:41 +0100288 * but that haven't been used.
289 *
290 * In fact on xen we mark RO the whole range pgt_buf_start -
291 * pgt_buf_top, because we have to make sure that when
292 * init_memory_mapping reaches the pagetable pages area, it maps
293 * RO all the pagetable pages, including the ones that are beyond
294 * pgt_buf_end at that time.
295 */
Yinghai Lud1b19422011-02-24 14:46:24 +0100296 if (!after_bootmem && pgt_buf_end > pgt_buf_start)
Stefano Stabellini279b7062011-04-14 15:49:41 +0100297 x86_init.mapping.pagetable_reserve(PFN_PHYS(pgt_buf_start),
298 PFN_PHYS(pgt_buf_end));
Pekka Enbergf7650902009-03-05 14:55:05 +0200299
300 if (!after_bootmem)
301 early_memtest(start, end);
302
303 return ret >> PAGE_SHIFT;
304}
305
Pekka Enberge5b2bb52009-03-03 13:15:06 +0200306
Pekka Enberg540aca02009-03-04 11:46:40 +0200307/*
308 * devmem_is_allowed() checks to see if /dev/mem access to a certain address
309 * is valid. The argument is a physical page number.
310 *
311 *
312 * On x86, access has to be given to the first megabyte of ram because that area
313 * contains bios code and data regions used by X and dosemu and similar apps.
314 * Access has to be given to non-kernel-ram areas as well, these contain the PCI
315 * mmio resources as well as potential bios/acpi data regions.
316 */
317int devmem_is_allowed(unsigned long pagenr)
318{
319 if (pagenr <= 256)
320 return 1;
321 if (iomem_is_exclusive(pagenr << PAGE_SHIFT))
322 return 0;
323 if (!page_is_ram(pagenr))
324 return 1;
325 return 0;
326}
327
Pekka Enberge5b2bb52009-03-03 13:15:06 +0200328void free_init_pages(char *what, unsigned long begin, unsigned long end)
329{
Yinghai Luc967da62010-03-28 19:42:55 -0700330 unsigned long addr;
331 unsigned long begin_aligned, end_aligned;
Pekka Enberge5b2bb52009-03-03 13:15:06 +0200332
Yinghai Luc967da62010-03-28 19:42:55 -0700333 /* Make sure boundaries are page aligned */
334 begin_aligned = PAGE_ALIGN(begin);
335 end_aligned = end & PAGE_MASK;
336
337 if (WARN_ON(begin_aligned != begin || end_aligned != end)) {
338 begin = begin_aligned;
339 end = end_aligned;
340 }
341
342 if (begin >= end)
Pekka Enberge5b2bb52009-03-03 13:15:06 +0200343 return;
344
Yinghai Luc967da62010-03-28 19:42:55 -0700345 addr = begin;
346
Pekka Enberge5b2bb52009-03-03 13:15:06 +0200347 /*
348 * If debugging page accesses then do not free this memory but
349 * mark them not present - any buggy init-section access will
350 * create a kernel page fault:
351 */
352#ifdef CONFIG_DEBUG_PAGEALLOC
353 printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n",
Yinghai Luc967da62010-03-28 19:42:55 -0700354 begin, end);
Pekka Enberge5b2bb52009-03-03 13:15:06 +0200355 set_memory_np(begin, (end - begin) >> PAGE_SHIFT);
356#else
357 /*
358 * We just marked the kernel text read only above, now that
359 * we are going to free part of that, we need to make that
Matthieu Castet5bd5a452010-11-16 22:31:26 +0100360 * writeable and non-executable first.
Pekka Enberge5b2bb52009-03-03 13:15:06 +0200361 */
Matthieu Castet5bd5a452010-11-16 22:31:26 +0100362 set_memory_nx(begin, (end - begin) >> PAGE_SHIFT);
Pekka Enberge5b2bb52009-03-03 13:15:06 +0200363 set_memory_rw(begin, (end - begin) >> PAGE_SHIFT);
364
365 printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
366
367 for (; addr < end; addr += PAGE_SIZE) {
368 ClearPageReserved(virt_to_page(addr));
369 init_page_count(virt_to_page(addr));
Yinghai Luc967da62010-03-28 19:42:55 -0700370 memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
Pekka Enberge5b2bb52009-03-03 13:15:06 +0200371 free_page(addr);
372 totalram_pages++;
373 }
374#endif
375}
376
377void free_initmem(void)
378{
379 free_init_pages("unused kernel memory",
380 (unsigned long)(&__init_begin),
381 (unsigned long)(&__init_end));
382}
Pekka Enberg731ddea2009-03-04 11:13:40 +0200383
384#ifdef CONFIG_BLK_DEV_INITRD
385void free_initrd_mem(unsigned long start, unsigned long end)
386{
Yinghai Luc967da62010-03-28 19:42:55 -0700387 /*
388 * end could be not aligned, and We can not align that,
389 * decompresser could be confused by aligned initrd_end
390 * We already reserve the end partial page before in
391 * - i386_start_kernel()
392 * - x86_64_start_kernel()
393 * - relocate_initrd()
394 * So here We can do PAGE_ALIGN() safely to get partial page to be freed
395 */
396 free_init_pages("initrd memory", start, PAGE_ALIGN(end));
Pekka Enberg731ddea2009-03-04 11:13:40 +0200397}
398#endif
Pekka Enberg17623912011-11-01 15:58:22 +0200399
400void __init zone_sizes_init(void)
401{
402 unsigned long max_zone_pfns[MAX_NR_ZONES];
403
404 memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
405
406#ifdef CONFIG_ZONE_DMA
407 max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
408#endif
409#ifdef CONFIG_ZONE_DMA32
410 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
411#endif
412 max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
413#ifdef CONFIG_HIGHMEM
414 max_zone_pfns[ZONE_HIGHMEM] = max_pfn;
415#endif
416
417 free_area_init_nodes(max_zone_pfns);
418}
419