lmb.c 11.6 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527
/*
 * Procedures for maintaining information about logical memory blocks.
 *
 * Peter Bergner, IBM Corp.	June 2001.
 * Copyright (C) 2001 Peter Bergner.
 *
 *      This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/bitops.h>
#include <linux/lmb.h>

#define LMB_ALLOC_ANYWHERE	0

struct lmb lmb;

static int lmb_debug;

static int __init early_lmb(char *p)
{
	if (p && strstr(p, "debug"))
		lmb_debug = 1;
	return 0;
}
early_param("lmb", early_lmb);

void lmb_dump_all(void)
{
	unsigned long i;

	if (!lmb_debug)
		return;

	pr_info("lmb_dump_all:\n");
	pr_info("    memory.cnt		  = 0x%lx\n", lmb.memory.cnt);
	pr_info("    memory.size		  = 0x%llx\n",
	    (unsigned long long)lmb.memory.size);
	for (i=0; i < lmb.memory.cnt ;i++) {
		pr_info("    memory.region[0x%lx].base       = 0x%llx\n",
		    i, (unsigned long long)lmb.memory.region[i].base);
		pr_info("		      .size     = 0x%llx\n",
		    (unsigned long long)lmb.memory.region[i].size);
	}

	pr_info("    reserved.cnt	  = 0x%lx\n", lmb.reserved.cnt);
	pr_info("    reserved.size	  = 0x%llx\n",
	    (unsigned long long)lmb.memory.size);
	for (i=0; i < lmb.reserved.cnt ;i++) {
		pr_info("    reserved.region[0x%lx].base       = 0x%llx\n",
		    i, (unsigned long long)lmb.reserved.region[i].base);
		pr_info("		      .size     = 0x%llx\n",
		    (unsigned long long)lmb.reserved.region[i].size);
	}
}

static unsigned long lmb_addrs_overlap(u64 base1, u64 size1, u64 base2,
					u64 size2)
{
	return ((base1 < (base2 + size2)) && (base2 < (base1 + size1)));
}

static long lmb_addrs_adjacent(u64 base1, u64 size1, u64 base2, u64 size2)
{
	if (base2 == base1 + size1)
		return 1;
	else if (base1 == base2 + size2)
		return -1;

	return 0;
}

static long lmb_regions_adjacent(struct lmb_region *rgn,
		unsigned long r1, unsigned long r2)
{
	u64 base1 = rgn->region[r1].base;
	u64 size1 = rgn->region[r1].size;
	u64 base2 = rgn->region[r2].base;
	u64 size2 = rgn->region[r2].size;

	return lmb_addrs_adjacent(base1, size1, base2, size2);
}

static void lmb_remove_region(struct lmb_region *rgn, unsigned long r)
{
	unsigned long i;

	for (i = r; i < rgn->cnt - 1; i++) {
		rgn->region[i].base = rgn->region[i + 1].base;
		rgn->region[i].size = rgn->region[i + 1].size;
	}
	rgn->cnt--;
}

/* Assumption: base addr of region 1 < base addr of region 2 */
static void lmb_coalesce_regions(struct lmb_region *rgn,
		unsigned long r1, unsigned long r2)
{
	rgn->region[r1].size += rgn->region[r2].size;
	lmb_remove_region(rgn, r2);
}

void __init lmb_init(void)
{
	/* Create a dummy zero size LMB which will get coalesced away later.
	 * This simplifies the lmb_add() code below...
	 */
	lmb.memory.region[0].base = 0;
	lmb.memory.region[0].size = 0;
	lmb.memory.cnt = 1;

	/* Ditto. */
	lmb.reserved.region[0].base = 0;
	lmb.reserved.region[0].size = 0;
	lmb.reserved.cnt = 1;
}

void __init lmb_analyze(void)
{
	int i;

	lmb.memory.size = 0;

	for (i = 0; i < lmb.memory.cnt; i++)
		lmb.memory.size += lmb.memory.region[i].size;
}

static long lmb_add_region(struct lmb_region *rgn, u64 base, u64 size)
{
	unsigned long coalesced = 0;
	long adjacent, i;

	if ((rgn->cnt == 1) && (rgn->region[0].size == 0)) {
		rgn->region[0].base = base;
		rgn->region[0].size = size;
		return 0;
	}

	/* First try and coalesce this LMB with another. */
	for (i = 0; i < rgn->cnt; i++) {
		u64 rgnbase = rgn->region[i].base;
		u64 rgnsize = rgn->region[i].size;

		if ((rgnbase == base) && (rgnsize == size))
			/* Already have this region, so we're done */
			return 0;

		adjacent = lmb_addrs_adjacent(base, size, rgnbase, rgnsize);
		if (adjacent > 0) {
			rgn->region[i].base -= size;
			rgn->region[i].size += size;
			coalesced++;
			break;
		} else if (adjacent < 0) {
			rgn->region[i].size += size;
			coalesced++;
			break;
		}
	}

	if ((i < rgn->cnt - 1) && lmb_regions_adjacent(rgn, i, i+1)) {
		lmb_coalesce_regions(rgn, i, i+1);
		coalesced++;
	}

	if (coalesced)
		return coalesced;
	if (rgn->cnt >= MAX_LMB_REGIONS)
		return -1;

	/* Couldn't coalesce the LMB, so add it to the sorted table. */
	for (i = rgn->cnt - 1; i >= 0; i--) {
		if (base < rgn->region[i].base) {
			rgn->region[i+1].base = rgn->region[i].base;
			rgn->region[i+1].size = rgn->region[i].size;
		} else {
			rgn->region[i+1].base = base;
			rgn->region[i+1].size = size;
			break;
		}
	}

	if (base < rgn->region[0].base) {
		rgn->region[0].base = base;
		rgn->region[0].size = size;
	}
	rgn->cnt++;

	return 0;
}

long lmb_add(u64 base, u64 size)
{
	struct lmb_region *_rgn = &lmb.memory;

	/* On pSeries LPAR systems, the first LMB is our RMO region. */
	if (base == 0)
		lmb.rmo_size = size;

	return lmb_add_region(_rgn, base, size);

}

long lmb_remove(u64 base, u64 size)
{
	struct lmb_region *rgn = &(lmb.memory);
	u64 rgnbegin, rgnend;
	u64 end = base + size;
	int i;

	rgnbegin = rgnend = 0; /* supress gcc warnings */

	/* Find the region where (base, size) belongs to */
	for (i=0; i < rgn->cnt; i++) {
		rgnbegin = rgn->region[i].base;
		rgnend = rgnbegin + rgn->region[i].size;

		if ((rgnbegin <= base) && (end <= rgnend))
			break;
	}

	/* Didn't find the region */
	if (i == rgn->cnt)
		return -1;

	/* Check to see if we are removing entire region */
	if ((rgnbegin == base) && (rgnend == end)) {
		lmb_remove_region(rgn, i);
		return 0;
	}

	/* Check to see if region is matching at the front */
	if (rgnbegin == base) {
		rgn->region[i].base = end;
		rgn->region[i].size -= size;
		return 0;
	}

	/* Check to see if the region is matching at the end */
	if (rgnend == end) {
		rgn->region[i].size -= size;
		return 0;
	}

	/*
	 * We need to split the entry -  adjust the current one to the
	 * beginging of the hole and add the region after hole.
	 */
	rgn->region[i].size = base - rgn->region[i].base;
	return lmb_add_region(rgn, end, rgnend - end);
}

long __init lmb_reserve(u64 base, u64 size)
{
	struct lmb_region *_rgn = &lmb.reserved;

	BUG_ON(0 == size);

	return lmb_add_region(_rgn, base, size);
}

long __init lmb_overlaps_region(struct lmb_region *rgn, u64 base, u64 size)
{
	unsigned long i;

	for (i = 0; i < rgn->cnt; i++) {
		u64 rgnbase = rgn->region[i].base;
		u64 rgnsize = rgn->region[i].size;
		if (lmb_addrs_overlap(base, size, rgnbase, rgnsize))
			break;
	}

	return (i < rgn->cnt) ? i : -1;
}

static u64 lmb_align_down(u64 addr, u64 size)
{
	return addr & ~(size - 1);
}

static u64 lmb_align_up(u64 addr, u64 size)
{
	return (addr + (size - 1)) & ~(size - 1);
}

static u64 __init lmb_alloc_nid_unreserved(u64 start, u64 end,
					   u64 size, u64 align)
{
	u64 base, res_base;
	long j;

	base = lmb_align_down((end - size), align);
	while (start <= base) {
		j = lmb_overlaps_region(&lmb.reserved, base, size);
		if (j < 0) {
			/* this area isn't reserved, take it */
			if (lmb_add_region(&lmb.reserved, base, size) < 0)
				base = ~(u64)0;
			return base;
		}
		res_base = lmb.reserved.region[j].base;
		if (res_base < size)
			break;
		base = lmb_align_down(res_base - size, align);
	}

	return ~(u64)0;
}

static u64 __init lmb_alloc_nid_region(struct lmb_property *mp,
				       u64 (*nid_range)(u64, u64, int *),
				       u64 size, u64 align, int nid)
{
	u64 start, end;

	start = mp->base;
	end = start + mp->size;

	start = lmb_align_up(start, align);
	while (start < end) {
		u64 this_end;
		int this_nid;

		this_end = nid_range(start, end, &this_nid);
		if (this_nid == nid) {
			u64 ret = lmb_alloc_nid_unreserved(start, this_end,
							   size, align);
			if (ret != ~(u64)0)
				return ret;
		}
		start = this_end;
	}

	return ~(u64)0;
}

u64 __init lmb_alloc_nid(u64 size, u64 align, int nid,
			 u64 (*nid_range)(u64 start, u64 end, int *nid))
{
	struct lmb_region *mem = &lmb.memory;
	int i;

	BUG_ON(0 == size);

	size = lmb_align_up(size, align);

	for (i = 0; i < mem->cnt; i++) {
		u64 ret = lmb_alloc_nid_region(&mem->region[i],
					       nid_range,
					       size, align, nid);
		if (ret != ~(u64)0)
			return ret;
	}

	return lmb_alloc(size, align);
}

u64 __init lmb_alloc(u64 size, u64 align)
{
	return lmb_alloc_base(size, align, LMB_ALLOC_ANYWHERE);
}

u64 __init lmb_alloc_base(u64 size, u64 align, u64 max_addr)
{
	u64 alloc;

	alloc = __lmb_alloc_base(size, align, max_addr);

	if (alloc == 0)
		panic("ERROR: Failed to allocate 0x%llx bytes below 0x%llx.\n",
		      (unsigned long long) size, (unsigned long long) max_addr);

	return alloc;
}

u64 __init __lmb_alloc_base(u64 size, u64 align, u64 max_addr)
{
	long i, j;
	u64 base = 0;
	u64 res_base;

	BUG_ON(0 == size);

	size = lmb_align_up(size, align);

	/* On some platforms, make sure we allocate lowmem */
	/* Note that LMB_REAL_LIMIT may be LMB_ALLOC_ANYWHERE */
	if (max_addr == LMB_ALLOC_ANYWHERE)
		max_addr = LMB_REAL_LIMIT;

	for (i = lmb.memory.cnt - 1; i >= 0; i--) {
		u64 lmbbase = lmb.memory.region[i].base;
		u64 lmbsize = lmb.memory.region[i].size;

		if (lmbsize < size)
			continue;
		if (max_addr == LMB_ALLOC_ANYWHERE)
			base = lmb_align_down(lmbbase + lmbsize - size, align);
		else if (lmbbase < max_addr) {
			base = min(lmbbase + lmbsize, max_addr);
			base = lmb_align_down(base - size, align);
		} else
			continue;

		while (base && lmbbase <= base) {
			j = lmb_overlaps_region(&lmb.reserved, base, size);
			if (j < 0) {
				/* this area isn't reserved, take it */
				if (lmb_add_region(&lmb.reserved, base, size) < 0)
					return 0;
				return base;
			}
			res_base = lmb.reserved.region[j].base;
			if (res_base < size)
				break;
			base = lmb_align_down(res_base - size, align);
		}
	}
	return 0;
}

/* You must call lmb_analyze() before this. */
u64 __init lmb_phys_mem_size(void)
{
	return lmb.memory.size;
}

u64 __init lmb_end_of_DRAM(void)
{
	int idx = lmb.memory.cnt - 1;

	return (lmb.memory.region[idx].base + lmb.memory.region[idx].size);
}

/* You must call lmb_analyze() after this. */
void __init lmb_enforce_memory_limit(u64 memory_limit)
{
	unsigned long i;
	u64 limit;
	struct lmb_property *p;

	if (!memory_limit)
		return;

	/* Truncate the lmb regions to satisfy the memory limit. */
	limit = memory_limit;
	for (i = 0; i < lmb.memory.cnt; i++) {
		if (limit > lmb.memory.region[i].size) {
			limit -= lmb.memory.region[i].size;
			continue;
		}

		lmb.memory.region[i].size = limit;
		lmb.memory.cnt = i + 1;
		break;
	}

	if (lmb.memory.region[0].size < lmb.rmo_size)
		lmb.rmo_size = lmb.memory.region[0].size;

	memory_limit = lmb_end_of_DRAM();

	/* And truncate any reserves above the limit also. */
	for (i = 0; i < lmb.reserved.cnt; i++) {
		p = &lmb.reserved.region[i];

		if (p->base > memory_limit)
			p->size = 0;
		else if ((p->base + p->size) > memory_limit)
			p->size = memory_limit - p->base;

		if (p->size == 0) {
			lmb_remove_region(&lmb.reserved, i);
			i--;
		}
	}
}

int __init lmb_is_reserved(u64 addr)
{
	int i;

	for (i = 0; i < lmb.reserved.cnt; i++) {
		u64 upper = lmb.reserved.region[i].base +
			lmb.reserved.region[i].size - 1;
		if ((addr >= lmb.reserved.region[i].base) && (addr <= upper))
			return 1;
	}
	return 0;
}

/*
 * Given a <base, len>, find which memory regions belong to this range.
 * Adjust the request and return a contiguous chunk.
 */
int lmb_find(struct lmb_property *res)
{
	int i;
	u64 rstart, rend;

	rstart = res->base;
	rend = rstart + res->size - 1;

	for (i = 0; i < lmb.memory.cnt; i++) {
		u64 start = lmb.memory.region[i].base;
		u64 end = start + lmb.memory.region[i].size - 1;

		if (start > rend)
			return -1;

		if ((end >= rstart) && (start < rend)) {
			/* adjust the request */
			if (rstart < start)
				rstart = start;
			if (rend > end)
				rend = end;
			res->base = rstart;
			res->size = rend - rstart + 1;
			return 0;
		}
	}
	return -1;
}