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authorFrederic Weisbecker <fweisbec@gmail.com>2010-05-12 17:19:01 -0400
committerFrederic Weisbecker <fweisbec@gmail.com>2010-05-12 17:20:33 -0400
commita9aa1d02de36b450990b0e25a88fc2ff1c3e6b94 (patch)
tree1f9d19f1642d263e65906a916a48be9339accc73 /kernel/early_res.c
parent5671a10e2bc7f99d9157c6044faf8be2ef302361 (diff)
parentb57f95a38233a2e73b679bea4a5453a1cc2a1cc9 (diff)
Merge commit 'v2.6.34-rc7' into perf/nmi
Merge reason: catch up with latest softlockup detector changes.
Diffstat (limited to 'kernel/early_res.c')
-rw-r--r--kernel/early_res.c584
1 files changed, 584 insertions, 0 deletions
diff --git a/kernel/early_res.c b/kernel/early_res.c
new file mode 100644
index 000000000000..31aa9332ef3f
--- /dev/null
+++ b/kernel/early_res.c
@@ -0,0 +1,584 @@
1/*
2 * early_res, could be used to replace bootmem
3 */
4#include <linux/kernel.h>
5#include <linux/types.h>
6#include <linux/init.h>
7#include <linux/bootmem.h>
8#include <linux/mm.h>
9#include <linux/early_res.h>
10
11/*
12 * Early reserved memory areas.
13 */
14/*
15 * need to make sure this one is bigger enough before
16 * find_fw_memmap_area could be used
17 */
18#define MAX_EARLY_RES_X 32
19
20struct early_res {
21 u64 start, end;
22 char name[15];
23 char overlap_ok;
24};
25static struct early_res early_res_x[MAX_EARLY_RES_X] __initdata;
26
27static int max_early_res __initdata = MAX_EARLY_RES_X;
28static struct early_res *early_res __initdata = &early_res_x[0];
29static int early_res_count __initdata;
30
31static int __init find_overlapped_early(u64 start, u64 end)
32{
33 int i;
34 struct early_res *r;
35
36 for (i = 0; i < max_early_res && early_res[i].end; i++) {
37 r = &early_res[i];
38 if (end > r->start && start < r->end)
39 break;
40 }
41
42 return i;
43}
44
45/*
46 * Drop the i-th range from the early reservation map,
47 * by copying any higher ranges down one over it, and
48 * clearing what had been the last slot.
49 */
50static void __init drop_range(int i)
51{
52 int j;
53
54 for (j = i + 1; j < max_early_res && early_res[j].end; j++)
55 ;
56
57 memmove(&early_res[i], &early_res[i + 1],
58 (j - 1 - i) * sizeof(struct early_res));
59
60 early_res[j - 1].end = 0;
61 early_res_count--;
62}
63
64static void __init drop_range_partial(int i, u64 start, u64 end)
65{
66 u64 common_start, common_end;
67 u64 old_start, old_end;
68
69 old_start = early_res[i].start;
70 old_end = early_res[i].end;
71 common_start = max(old_start, start);
72 common_end = min(old_end, end);
73
74 /* no overlap ? */
75 if (common_start >= common_end)
76 return;
77
78 if (old_start < common_start) {
79 /* make head segment */
80 early_res[i].end = common_start;
81 if (old_end > common_end) {
82 char name[15];
83
84 /*
85 * Save a local copy of the name, since the
86 * early_res array could get resized inside
87 * reserve_early_without_check() ->
88 * __check_and_double_early_res(), which would
89 * make the current name pointer invalid.
90 */
91 strncpy(name, early_res[i].name,
92 sizeof(early_res[i].name) - 1);
93 /* add another for left over on tail */
94 reserve_early_without_check(common_end, old_end, name);
95 }
96 return;
97 } else {
98 if (old_end > common_end) {
99 /* reuse the entry for tail left */
100 early_res[i].start = common_end;
101 return;
102 }
103 /* all covered */
104 drop_range(i);
105 }
106}
107
108/*
109 * Split any existing ranges that:
110 * 1) are marked 'overlap_ok', and
111 * 2) overlap with the stated range [start, end)
112 * into whatever portion (if any) of the existing range is entirely
113 * below or entirely above the stated range. Drop the portion
114 * of the existing range that overlaps with the stated range,
115 * which will allow the caller of this routine to then add that
116 * stated range without conflicting with any existing range.
117 */
118static void __init drop_overlaps_that_are_ok(u64 start, u64 end)
119{
120 int i;
121 struct early_res *r;
122 u64 lower_start, lower_end;
123 u64 upper_start, upper_end;
124 char name[15];
125
126 for (i = 0; i < max_early_res && early_res[i].end; i++) {
127 r = &early_res[i];
128
129 /* Continue past non-overlapping ranges */
130 if (end <= r->start || start >= r->end)
131 continue;
132
133 /*
134 * Leave non-ok overlaps as is; let caller
135 * panic "Overlapping early reservations"
136 * when it hits this overlap.
137 */
138 if (!r->overlap_ok)
139 return;
140
141 /*
142 * We have an ok overlap. We will drop it from the early
143 * reservation map, and add back in any non-overlapping
144 * portions (lower or upper) as separate, overlap_ok,
145 * non-overlapping ranges.
146 */
147
148 /* 1. Note any non-overlapping (lower or upper) ranges. */
149 strncpy(name, r->name, sizeof(name) - 1);
150
151 lower_start = lower_end = 0;
152 upper_start = upper_end = 0;
153 if (r->start < start) {
154 lower_start = r->start;
155 lower_end = start;
156 }
157 if (r->end > end) {
158 upper_start = end;
159 upper_end = r->end;
160 }
161
162 /* 2. Drop the original ok overlapping range */
163 drop_range(i);
164
165 i--; /* resume for-loop on copied down entry */
166
167 /* 3. Add back in any non-overlapping ranges. */
168 if (lower_end)
169 reserve_early_overlap_ok(lower_start, lower_end, name);
170 if (upper_end)
171 reserve_early_overlap_ok(upper_start, upper_end, name);
172 }
173}
174
175static void __init __reserve_early(u64 start, u64 end, char *name,
176 int overlap_ok)
177{
178 int i;
179 struct early_res *r;
180
181 i = find_overlapped_early(start, end);
182 if (i >= max_early_res)
183 panic("Too many early reservations");
184 r = &early_res[i];
185 if (r->end)
186 panic("Overlapping early reservations "
187 "%llx-%llx %s to %llx-%llx %s\n",
188 start, end - 1, name ? name : "", r->start,
189 r->end - 1, r->name);
190 r->start = start;
191 r->end = end;
192 r->overlap_ok = overlap_ok;
193 if (name)
194 strncpy(r->name, name, sizeof(r->name) - 1);
195 early_res_count++;
196}
197
198/*
199 * A few early reservtations come here.
200 *
201 * The 'overlap_ok' in the name of this routine does -not- mean it
202 * is ok for these reservations to overlap an earlier reservation.
203 * Rather it means that it is ok for subsequent reservations to
204 * overlap this one.
205 *
206 * Use this entry point to reserve early ranges when you are doing
207 * so out of "Paranoia", reserving perhaps more memory than you need,
208 * just in case, and don't mind a subsequent overlapping reservation
209 * that is known to be needed.
210 *
211 * The drop_overlaps_that_are_ok() call here isn't really needed.
212 * It would be needed if we had two colliding 'overlap_ok'
213 * reservations, so that the second such would not panic on the
214 * overlap with the first. We don't have any such as of this
215 * writing, but might as well tolerate such if it happens in
216 * the future.
217 */
218void __init reserve_early_overlap_ok(u64 start, u64 end, char *name)
219{
220 drop_overlaps_that_are_ok(start, end);
221 __reserve_early(start, end, name, 1);
222}
223
224static void __init __check_and_double_early_res(u64 ex_start, u64 ex_end)
225{
226 u64 start, end, size, mem;
227 struct early_res *new;
228
229 /* do we have enough slots left ? */
230 if ((max_early_res - early_res_count) > max(max_early_res/8, 2))
231 return;
232
233 /* double it */
234 mem = -1ULL;
235 size = sizeof(struct early_res) * max_early_res * 2;
236 if (early_res == early_res_x)
237 start = 0;
238 else
239 start = early_res[0].end;
240 end = ex_start;
241 if (start + size < end)
242 mem = find_fw_memmap_area(start, end, size,
243 sizeof(struct early_res));
244 if (mem == -1ULL) {
245 start = ex_end;
246 end = get_max_mapped();
247 if (start + size < end)
248 mem = find_fw_memmap_area(start, end, size,
249 sizeof(struct early_res));
250 }
251 if (mem == -1ULL)
252 panic("can not find more space for early_res array");
253
254 new = __va(mem);
255 /* save the first one for own */
256 new[0].start = mem;
257 new[0].end = mem + size;
258 new[0].overlap_ok = 0;
259 /* copy old to new */
260 if (early_res == early_res_x) {
261 memcpy(&new[1], &early_res[0],
262 sizeof(struct early_res) * max_early_res);
263 memset(&new[max_early_res+1], 0,
264 sizeof(struct early_res) * (max_early_res - 1));
265 early_res_count++;
266 } else {
267 memcpy(&new[1], &early_res[1],
268 sizeof(struct early_res) * (max_early_res - 1));
269 memset(&new[max_early_res], 0,
270 sizeof(struct early_res) * max_early_res);
271 }
272 memset(&early_res[0], 0, sizeof(struct early_res) * max_early_res);
273 early_res = new;
274 max_early_res *= 2;
275 printk(KERN_DEBUG "early_res array is doubled to %d at [%llx - %llx]\n",
276 max_early_res, mem, mem + size - 1);
277}
278
279/*
280 * Most early reservations come here.
281 *
282 * We first have drop_overlaps_that_are_ok() drop any pre-existing
283 * 'overlap_ok' ranges, so that we can then reserve this memory
284 * range without risk of panic'ing on an overlapping overlap_ok
285 * early reservation.
286 */
287void __init reserve_early(u64 start, u64 end, char *name)
288{
289 if (start >= end)
290 return;
291
292 __check_and_double_early_res(start, end);
293
294 drop_overlaps_that_are_ok(start, end);
295 __reserve_early(start, end, name, 0);
296}
297
298void __init reserve_early_without_check(u64 start, u64 end, char *name)
299{
300 struct early_res *r;
301
302 if (start >= end)
303 return;
304
305 __check_and_double_early_res(start, end);
306
307 r = &early_res[early_res_count];
308
309 r->start = start;
310 r->end = end;
311 r->overlap_ok = 0;
312 if (name)
313 strncpy(r->name, name, sizeof(r->name) - 1);
314 early_res_count++;
315}
316
317void __init free_early(u64 start, u64 end)
318{
319 struct early_res *r;
320 int i;
321
322 i = find_overlapped_early(start, end);
323 r = &early_res[i];
324 if (i >= max_early_res || r->end != end || r->start != start)
325 panic("free_early on not reserved area: %llx-%llx!",
326 start, end - 1);
327
328 drop_range(i);
329}
330
331void __init free_early_partial(u64 start, u64 end)
332{
333 struct early_res *r;
334 int i;
335
336 if (start == end)
337 return;
338
339 if (WARN_ONCE(start > end, " wrong range [%#llx, %#llx]\n", start, end))
340 return;
341
342try_next:
343 i = find_overlapped_early(start, end);
344 if (i >= max_early_res)
345 return;
346
347 r = &early_res[i];
348 /* hole ? */
349 if (r->end >= end && r->start <= start) {
350 drop_range_partial(i, start, end);
351 return;
352 }
353
354 drop_range_partial(i, start, end);
355 goto try_next;
356}
357
358#ifdef CONFIG_NO_BOOTMEM
359static void __init subtract_early_res(struct range *range, int az)
360{
361 int i, count;
362 u64 final_start, final_end;
363 int idx = 0;
364
365 count = 0;
366 for (i = 0; i < max_early_res && early_res[i].end; i++)
367 count++;
368
369 /* need to skip first one ?*/
370 if (early_res != early_res_x)
371 idx = 1;
372
373#define DEBUG_PRINT_EARLY_RES 1
374
375#if DEBUG_PRINT_EARLY_RES
376 printk(KERN_INFO "Subtract (%d early reservations)\n", count);
377#endif
378 for (i = idx; i < count; i++) {
379 struct early_res *r = &early_res[i];
380#if DEBUG_PRINT_EARLY_RES
381 printk(KERN_INFO " #%d [%010llx - %010llx] %15s\n", i,
382 r->start, r->end, r->name);
383#endif
384 final_start = PFN_DOWN(r->start);
385 final_end = PFN_UP(r->end);
386 if (final_start >= final_end)
387 continue;
388 subtract_range(range, az, final_start, final_end);
389 }
390
391}
392
393int __init get_free_all_memory_range(struct range **rangep, int nodeid)
394{
395 int i, count;
396 u64 start = 0, end;
397 u64 size;
398 u64 mem;
399 struct range *range;
400 int nr_range;
401
402 count = 0;
403 for (i = 0; i < max_early_res && early_res[i].end; i++)
404 count++;
405
406 count *= 2;
407
408 size = sizeof(struct range) * count;
409 end = get_max_mapped();
410#ifdef MAX_DMA32_PFN
411 if (end > (MAX_DMA32_PFN << PAGE_SHIFT))
412 start = MAX_DMA32_PFN << PAGE_SHIFT;
413#endif
414 mem = find_fw_memmap_area(start, end, size, sizeof(struct range));
415 if (mem == -1ULL)
416 panic("can not find more space for range free");
417
418 range = __va(mem);
419 /* use early_node_map[] and early_res to get range array at first */
420 memset(range, 0, size);
421 nr_range = 0;
422
423 /* need to go over early_node_map to find out good range for node */
424 nr_range = add_from_early_node_map(range, count, nr_range, nodeid);
425#ifdef CONFIG_X86_32
426 subtract_range(range, count, max_low_pfn, -1ULL);
427#endif
428 subtract_early_res(range, count);
429 nr_range = clean_sort_range(range, count);
430
431 /* need to clear it ? */
432 if (nodeid == MAX_NUMNODES) {
433 memset(&early_res[0], 0,
434 sizeof(struct early_res) * max_early_res);
435 early_res = NULL;
436 max_early_res = 0;
437 }
438
439 *rangep = range;
440 return nr_range;
441}
442#else
443void __init early_res_to_bootmem(u64 start, u64 end)
444{
445 int i, count;
446 u64 final_start, final_end;
447 int idx = 0;
448
449 count = 0;
450 for (i = 0; i < max_early_res && early_res[i].end; i++)
451 count++;
452
453 /* need to skip first one ?*/
454 if (early_res != early_res_x)
455 idx = 1;
456
457 printk(KERN_INFO "(%d/%d early reservations) ==> bootmem [%010llx - %010llx]\n",
458 count - idx, max_early_res, start, end);
459 for (i = idx; i < count; i++) {
460 struct early_res *r = &early_res[i];
461 printk(KERN_INFO " #%d [%010llx - %010llx] %16s", i,
462 r->start, r->end, r->name);
463 final_start = max(start, r->start);
464 final_end = min(end, r->end);
465 if (final_start >= final_end) {
466 printk(KERN_CONT "\n");
467 continue;
468 }
469 printk(KERN_CONT " ==> [%010llx - %010llx]\n",
470 final_start, final_end);
471 reserve_bootmem_generic(final_start, final_end - final_start,
472 BOOTMEM_DEFAULT);
473 }
474 /* clear them */
475 memset(&early_res[0], 0, sizeof(struct early_res) * max_early_res);
476 early_res = NULL;
477 max_early_res = 0;
478 early_res_count = 0;
479}
480#endif
481
482/* Check for already reserved areas */
483static inline int __init bad_addr(u64 *addrp, u64 size, u64 align)
484{
485 int i;
486 u64 addr = *addrp;
487 int changed = 0;
488 struct early_res *r;
489again:
490 i = find_overlapped_early(addr, addr + size);
491 r = &early_res[i];
492 if (i < max_early_res && r->end) {
493 *addrp = addr = round_up(r->end, align);
494 changed = 1;
495 goto again;
496 }
497 return changed;
498}
499
500/* Check for already reserved areas */
501static inline int __init bad_addr_size(u64 *addrp, u64 *sizep, u64 align)
502{
503 int i;
504 u64 addr = *addrp, last;
505 u64 size = *sizep;
506 int changed = 0;
507again:
508 last = addr + size;
509 for (i = 0; i < max_early_res && early_res[i].end; i++) {
510 struct early_res *r = &early_res[i];
511 if (last > r->start && addr < r->start) {
512 size = r->start - addr;
513 changed = 1;
514 goto again;
515 }
516 if (last > r->end && addr < r->end) {
517 addr = round_up(r->end, align);
518 size = last - addr;
519 changed = 1;
520 goto again;
521 }
522 if (last <= r->end && addr >= r->start) {
523 (*sizep)++;
524 return 0;
525 }
526 }
527 if (changed) {
528 *addrp = addr;
529 *sizep = size;
530 }
531 return changed;
532}
533
534/*
535 * Find a free area with specified alignment in a specific range.
536 * only with the area.between start to end is active range from early_node_map
537 * so they are good as RAM
538 */
539u64 __init find_early_area(u64 ei_start, u64 ei_last, u64 start, u64 end,
540 u64 size, u64 align)
541{
542 u64 addr, last;
543
544 addr = round_up(ei_start, align);
545 if (addr < start)
546 addr = round_up(start, align);
547 if (addr >= ei_last)
548 goto out;
549 while (bad_addr(&addr, size, align) && addr+size <= ei_last)
550 ;
551 last = addr + size;
552 if (last > ei_last)
553 goto out;
554 if (last > end)
555 goto out;
556
557 return addr;
558
559out:
560 return -1ULL;
561}
562
563u64 __init find_early_area_size(u64 ei_start, u64 ei_last, u64 start,
564 u64 *sizep, u64 align)
565{
566 u64 addr, last;
567
568 addr = round_up(ei_start, align);
569 if (addr < start)
570 addr = round_up(start, align);
571 if (addr >= ei_last)
572 goto out;
573 *sizep = ei_last - addr;
574 while (bad_addr_size(&addr, sizep, align) && addr + *sizep <= ei_last)
575 ;
576 last = addr + *sizep;
577 if (last > ei_last)
578 goto out;
579
580 return addr;
581
582out:
583 return -1ULL;
584}