Create 'k' versions of the kernel malloc API.
[dragonfly.git] / sys / kern / kern_slaballoc.c
CommitLineData
a108bf71 1/*
5b287bba 2 * KERN_SLABALLOC.C - Kernel SLAB memory allocator
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3 *
4 * Copyright (c) 2003,2004 The DragonFly Project. All rights reserved.
5 *
6 * This code is derived from software contributed to The DragonFly Project
7 * by Matthew Dillon <dillon@backplane.com>
8 *
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9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
8c10bfcf 12 *
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13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
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16 * notice, this list of conditions and the following disclaimer in
17 * the documentation and/or other materials provided with the
18 * distribution.
19 * 3. Neither the name of The DragonFly Project nor the names of its
20 * contributors may be used to endorse or promote products derived
21 * from this software without specific, prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
24 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
26 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
27 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
28 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
29 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
30 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
31 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
32 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
33 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
a108bf71 34 * SUCH DAMAGE.
8c10bfcf 35 *
8aca2bd4 36 * $DragonFly: src/sys/kern/kern_slaballoc.c,v 1.40 2006/09/04 23:03:36 dillon Exp $
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37 *
38 * This module implements a slab allocator drop-in replacement for the
39 * kernel malloc().
40 *
41 * A slab allocator reserves a ZONE for each chunk size, then lays the
42 * chunks out in an array within the zone. Allocation and deallocation
43 * is nearly instantanious, and fragmentation/overhead losses are limited
44 * to a fixed worst-case amount.
45 *
46 * The downside of this slab implementation is in the chunk size
47 * multiplied by the number of zones. ~80 zones * 128K = 10MB of VM per cpu.
48 * In a kernel implementation all this memory will be physical so
49 * the zone size is adjusted downward on machines with less physical
50 * memory. The upside is that overhead is bounded... this is the *worst*
51 * case overhead.
52 *
53 * Slab management is done on a per-cpu basis and no locking or mutexes
54 * are required, only a critical section. When one cpu frees memory
55 * belonging to another cpu's slab manager an asynchronous IPI message
56 * will be queued to execute the operation. In addition, both the
57 * high level slab allocator and the low level zone allocator optimize
58 * M_ZERO requests, and the slab allocator does not have to pre initialize
59 * the linked list of chunks.
60 *
61 * XXX Balancing is needed between cpus. Balance will be handled through
62 * asynchronous IPIs primarily by reassigning the z_Cpu ownership of chunks.
63 *
64 * XXX If we have to allocate a new zone and M_USE_RESERVE is set, use of
65 * the new zone should be restricted to M_USE_RESERVE requests only.
66 *
67 * Alloc Size Chunking Number of zones
68 * 0-127 8 16
69 * 128-255 16 8
70 * 256-511 32 8
71 * 512-1023 64 8
72 * 1024-2047 128 8
73 * 2048-4095 256 8
74 * 4096-8191 512 8
75 * 8192-16383 1024 8
76 * 16384-32767 2048 8
77 * (if PAGE_SIZE is 4K the maximum zone allocation is 16383)
78 *
46a3f46d 79 * Allocations >= ZoneLimit go directly to kmem.
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80 *
81 * API REQUIREMENTS AND SIDE EFFECTS
82 *
83 * To operate as a drop-in replacement to the FreeBSD-4.x malloc() we
84 * have remained compatible with the following API requirements:
85 *
86 * + small power-of-2 sized allocations are power-of-2 aligned (kern_tty)
3d177b31 87 * + all power-of-2 sized allocations are power-of-2 aligned (twe)
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88 * + malloc(0) is allowed and returns non-NULL (ahc driver)
89 * + ability to allocate arbitrarily large chunks of memory
90 */
91
92#include "opt_vm.h"
93
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94#include <sys/param.h>
95#include <sys/systm.h>
96#include <sys/kernel.h>
97#include <sys/slaballoc.h>
98#include <sys/mbuf.h>
99#include <sys/vmmeter.h>
100#include <sys/lock.h>
101#include <sys/thread.h>
102#include <sys/globaldata.h>
d2182dc1 103#include <sys/sysctl.h>
f2b5daf9 104#include <sys/ktr.h>
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105
106#include <vm/vm.h>
107#include <vm/vm_param.h>
108#include <vm/vm_kern.h>
109#include <vm/vm_extern.h>
110#include <vm/vm_object.h>
111#include <vm/pmap.h>
112#include <vm/vm_map.h>
113#include <vm/vm_page.h>
114#include <vm/vm_pageout.h>
115
116#include <machine/cpu.h>
117
118#include <sys/thread2.h>
119
120#define arysize(ary) (sizeof(ary)/sizeof((ary)[0]))
121
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122#define MEMORY_STRING "ptr=%p type=%p size=%d flags=%04x"
123#define MEMORY_ARG_SIZE (sizeof(void *) * 2 + sizeof(unsigned long) + \
124 sizeof(int))
125
126#if !defined(KTR_MEMORY)
127#define KTR_MEMORY KTR_ALL
128#endif
129KTR_INFO_MASTER(memory);
130KTR_INFO(KTR_MEMORY, memory, malloc, 0, MEMORY_STRING, MEMORY_ARG_SIZE);
131KTR_INFO(KTR_MEMORY, memory, free_zero, 1, MEMORY_STRING, MEMORY_ARG_SIZE);
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132KTR_INFO(KTR_MEMORY, memory, free_ovsz, 2, MEMORY_STRING, MEMORY_ARG_SIZE);
133KTR_INFO(KTR_MEMORY, memory, free_ovsz_delayed, 3, MEMORY_STRING, MEMORY_ARG_SIZE);
134KTR_INFO(KTR_MEMORY, memory, free_chunk, 4, MEMORY_STRING, MEMORY_ARG_SIZE);
f2b5daf9 135#ifdef SMP
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136KTR_INFO(KTR_MEMORY, memory, free_request, 5, MEMORY_STRING, MEMORY_ARG_SIZE);
137KTR_INFO(KTR_MEMORY, memory, free_remote, 6, MEMORY_STRING, MEMORY_ARG_SIZE);
f2b5daf9 138#endif
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139KTR_INFO(KTR_MEMORY, memory, malloc_beg, 0, "malloc begin", 0);
140KTR_INFO(KTR_MEMORY, memory, free_beg, 0, "free begin", 0);
141KTR_INFO(KTR_MEMORY, memory, free_end, 0, "free end", 0);
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142
143#define logmemory(name, ptr, type, size, flags) \
144 KTR_LOG(memory_ ## name, ptr, type, size, flags)
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145#define logmemory_quick(name) \
146 KTR_LOG(memory_ ## name)
f2b5daf9 147
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148/*
149 * Fixed globals (not per-cpu)
150 */
151static int ZoneSize;
46a3f46d 152static int ZoneLimit;
a108bf71 153static int ZonePageCount;
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154static int ZoneMask;
155static struct malloc_type *kmemstatistics;
156static struct kmemusage *kmemusage;
157static int32_t weirdary[16];
158
159static void *kmem_slab_alloc(vm_size_t bytes, vm_offset_t align, int flags);
160static void kmem_slab_free(void *ptr, vm_size_t bytes);
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161#if defined(INVARIANTS)
162static void chunk_mark_allocated(SLZone *z, void *chunk);
163static void chunk_mark_free(SLZone *z, void *chunk);
164#endif
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165
166/*
167 * Misc constants. Note that allocations that are exact multiples of
168 * PAGE_SIZE, or exceed the zone limit, fall through to the kmem module.
169 * IN_SAME_PAGE_MASK is used to sanity-check the per-page free lists.
170 */
171#define MIN_CHUNK_SIZE 8 /* in bytes */
172#define MIN_CHUNK_MASK (MIN_CHUNK_SIZE - 1)
173#define ZONE_RELS_THRESH 2 /* threshold number of zones */
174#define IN_SAME_PAGE_MASK (~(intptr_t)PAGE_MASK | MIN_CHUNK_MASK)
175
176/*
177 * The WEIRD_ADDR is used as known text to copy into free objects to
178 * try to create deterministic failure cases if the data is accessed after
179 * free.
180 */
181#define WEIRD_ADDR 0xdeadc0de
182#define MAX_COPY sizeof(weirdary)
183#define ZERO_LENGTH_PTR ((void *)-8)
184
185/*
186 * Misc global malloc buckets
187 */
188
189MALLOC_DEFINE(M_CACHE, "cache", "Various Dynamically allocated caches");
190MALLOC_DEFINE(M_DEVBUF, "devbuf", "device driver memory");
191MALLOC_DEFINE(M_TEMP, "temp", "misc temporary data buffers");
192
193MALLOC_DEFINE(M_IP6OPT, "ip6opt", "IPv6 options");
194MALLOC_DEFINE(M_IP6NDP, "ip6ndp", "IPv6 Neighbor Discovery");
195
196/*
197 * Initialize the slab memory allocator. We have to choose a zone size based
198 * on available physical memory. We choose a zone side which is approximately
199 * 1/1024th of our memory, so if we have 128MB of ram we have a zone size of
200 * 128K. The zone size is limited to the bounds set in slaballoc.h
201 * (typically 32K min, 128K max).
202 */
203static void kmeminit(void *dummy);
204
205SYSINIT(kmem, SI_SUB_KMEM, SI_ORDER_FIRST, kmeminit, NULL)
206
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207#ifdef INVARIANTS
208/*
209 * If enabled any memory allocated without M_ZERO is initialized to -1.
210 */
211static int use_malloc_pattern;
212SYSCTL_INT(_debug, OID_AUTO, use_malloc_pattern, CTLFLAG_RW,
213 &use_malloc_pattern, 0, "");
214#endif
215
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216static void
217kmeminit(void *dummy)
218{
219 vm_poff_t limsize;
220 int usesize;
221 int i;
222 vm_pindex_t npg;
223
224 limsize = (vm_poff_t)vmstats.v_page_count * PAGE_SIZE;
225 if (limsize > VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS)
226 limsize = VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS;
227
228 usesize = (int)(limsize / 1024); /* convert to KB */
229
230 ZoneSize = ZALLOC_MIN_ZONE_SIZE;
231 while (ZoneSize < ZALLOC_MAX_ZONE_SIZE && (ZoneSize << 1) < usesize)
232 ZoneSize <<= 1;
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233 ZoneLimit = ZoneSize / 4;
234 if (ZoneLimit > ZALLOC_ZONE_LIMIT)
235 ZoneLimit = ZALLOC_ZONE_LIMIT;
a108bf71 236 ZoneMask = ZoneSize - 1;
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237 ZonePageCount = ZoneSize / PAGE_SIZE;
238
239 npg = (VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS) / PAGE_SIZE;
dc1fd4b3 240 kmemusage = kmem_slab_alloc(npg * sizeof(struct kmemusage), PAGE_SIZE, M_WAITOK|M_ZERO);
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241
242 for (i = 0; i < arysize(weirdary); ++i)
243 weirdary[i] = WEIRD_ADDR;
244
245 if (bootverbose)
246 printf("Slab ZoneSize set to %dKB\n", ZoneSize / 1024);
247}
248
249/*
bba6a44d 250 * Initialize a malloc type tracking structure.
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251 */
252void
253malloc_init(void *data)
254{
255 struct malloc_type *type = data;
256 vm_poff_t limsize;
257
258 if (type->ks_magic != M_MAGIC)
259 panic("malloc type lacks magic");
260
261 if (type->ks_limit != 0)
262 return;
263
264 if (vmstats.v_page_count == 0)
265 panic("malloc_init not allowed before vm init");
266
267 limsize = (vm_poff_t)vmstats.v_page_count * PAGE_SIZE;
268 if (limsize > VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS)
269 limsize = VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS;
270 type->ks_limit = limsize / 10;
271
272 type->ks_next = kmemstatistics;
273 kmemstatistics = type;
274}
275
276void
277malloc_uninit(void *data)
278{
279 struct malloc_type *type = data;
280 struct malloc_type *t;
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281#ifdef INVARIANTS
282 int i;
1d712609 283 long ttl;
bba6a44d 284#endif
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285
286 if (type->ks_magic != M_MAGIC)
287 panic("malloc type lacks magic");
288
289 if (vmstats.v_page_count == 0)
290 panic("malloc_uninit not allowed before vm init");
291
292 if (type->ks_limit == 0)
293 panic("malloc_uninit on uninitialized type");
294
295#ifdef INVARIANTS
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296 /*
297 * memuse is only correct in aggregation. Due to memory being allocated
298 * on one cpu and freed on another individual array entries may be
299 * negative or positive (canceling each other out).
300 */
301 for (i = ttl = 0; i < ncpus; ++i)
302 ttl += type->ks_memuse[i];
303 if (ttl) {
304 printf("malloc_uninit: %ld bytes of '%s' still allocated on cpu %d\n",
305 ttl, type->ks_shortdesc, i);
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306 }
307#endif
308 if (type == kmemstatistics) {
309 kmemstatistics = type->ks_next;
310 } else {
311 for (t = kmemstatistics; t->ks_next != NULL; t = t->ks_next) {
312 if (t->ks_next == type) {
313 t->ks_next = type->ks_next;
314 break;
315 }
316 }
317 }
318 type->ks_next = NULL;
319 type->ks_limit = 0;
320}
321
322/*
323 * Calculate the zone index for the allocation request size and set the
324 * allocation request size to that particular zone's chunk size.
325 */
326static __inline int
327zoneindex(unsigned long *bytes)
328{
329 unsigned int n = (unsigned int)*bytes; /* unsigned for shift opt */
330 if (n < 128) {
331 *bytes = n = (n + 7) & ~7;
332 return(n / 8 - 1); /* 8 byte chunks, 16 zones */
333 }
334 if (n < 256) {
335 *bytes = n = (n + 15) & ~15;
336 return(n / 16 + 7);
337 }
338 if (n < 8192) {
339 if (n < 512) {
340 *bytes = n = (n + 31) & ~31;
341 return(n / 32 + 15);
342 }
343 if (n < 1024) {
344 *bytes = n = (n + 63) & ~63;
345 return(n / 64 + 23);
346 }
347 if (n < 2048) {
348 *bytes = n = (n + 127) & ~127;
349 return(n / 128 + 31);
350 }
351 if (n < 4096) {
352 *bytes = n = (n + 255) & ~255;
353 return(n / 256 + 39);
354 }
355 *bytes = n = (n + 511) & ~511;
356 return(n / 512 + 47);
357 }
358#if ZALLOC_ZONE_LIMIT > 8192
359 if (n < 16384) {
360 *bytes = n = (n + 1023) & ~1023;
361 return(n / 1024 + 55);
362 }
363#endif
364#if ZALLOC_ZONE_LIMIT > 16384
365 if (n < 32768) {
366 *bytes = n = (n + 2047) & ~2047;
367 return(n / 2048 + 63);
368 }
369#endif
370 panic("Unexpected byte count %d", n);
371 return(0);
372}
373
374/*
5b287bba 375 * malloc() (SLAB ALLOCATOR)
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376 *
377 * Allocate memory via the slab allocator. If the request is too large,
378 * or if it page-aligned beyond a certain size, we fall back to the
379 * KMEM subsystem. A SLAB tracking descriptor must be specified, use
380 * &SlabMisc if you don't care.
381 *
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382 * M_RNOWAIT - don't block.
383 * M_NULLOK - return NULL instead of blocking.
a108bf71 384 * M_ZERO - zero the returned memory.
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385 * M_USE_RESERVE - allow greater drawdown of the free list
386 * M_USE_INTERRUPT_RESERVE - allow the freelist to be exhausted
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387 *
388 * MPSAFE
a108bf71 389 */
8aca2bd4 390
a108bf71 391void *
8aca2bd4 392kmalloc(unsigned long size, struct malloc_type *type, int flags)
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393{
394 SLZone *z;
395 SLChunk *chunk;
396 SLGlobalData *slgd;
bba6a44d 397 struct globaldata *gd;
a108bf71 398 int zi;
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399#ifdef INVARIANTS
400 int i;
401#endif
a108bf71 402
b68ad50c 403 logmemory_quick(malloc_beg);
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404 gd = mycpu;
405 slgd = &gd->gd_slab;
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406
407 /*
408 * XXX silly to have this in the critical path.
409 */
410 if (type->ks_limit == 0) {
411 crit_enter();
412 if (type->ks_limit == 0)
413 malloc_init(type);
414 crit_exit();
415 }
416 ++type->ks_calls;
417
418 /*
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419 * Handle the case where the limit is reached. Panic if we can't return
420 * NULL. The original malloc code looped, but this tended to
a108bf71 421 * simply deadlock the computer.
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422 *
423 * ks_loosememuse is an up-only limit that is NOT MP-synchronized, used
424 * to determine if a more complete limit check should be done. The
425 * actual memory use is tracked via ks_memuse[cpu].
a108bf71 426 */
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427 while (type->ks_loosememuse >= type->ks_limit) {
428 int i;
429 long ttl;
430
431 for (i = ttl = 0; i < ncpus; ++i)
432 ttl += type->ks_memuse[i];
38e34349 433 type->ks_loosememuse = ttl; /* not MP synchronized */
bba6a44d 434 if (ttl >= type->ks_limit) {
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435 if (flags & M_NULLOK) {
436 logmemory(malloc, NULL, type, size, flags);
bba6a44d 437 return(NULL);
f2b5daf9 438 }
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439 panic("%s: malloc limit exceeded", type->ks_shortdesc);
440 }
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441 }
442
443 /*
444 * Handle the degenerate size == 0 case. Yes, this does happen.
445 * Return a special pointer. This is to maintain compatibility with
446 * the original malloc implementation. Certain devices, such as the
447 * adaptec driver, not only allocate 0 bytes, they check for NULL and
448 * also realloc() later on. Joy.
449 */
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450 if (size == 0) {
451 logmemory(malloc, ZERO_LENGTH_PTR, type, size, flags);
a108bf71 452 return(ZERO_LENGTH_PTR);
f2b5daf9 453 }
a108bf71 454
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455 /*
456 * Handle hysteresis from prior frees here in malloc(). We cannot
457 * safely manipulate the kernel_map in free() due to free() possibly
458 * being called via an IPI message or from sensitive interrupt code.
459 */
dc1fd4b3 460 while (slgd->NFreeZones > ZONE_RELS_THRESH && (flags & M_RNOWAIT) == 0) {
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461 crit_enter();
462 if (slgd->NFreeZones > ZONE_RELS_THRESH) { /* crit sect race */
463 z = slgd->FreeZones;
464 slgd->FreeZones = z->z_Next;
465 --slgd->NFreeZones;
466 kmem_slab_free(z, ZoneSize); /* may block */
467 }
468 crit_exit();
469 }
470 /*
471 * XXX handle oversized frees that were queued from free().
472 */
dc1fd4b3 473 while (slgd->FreeOvZones && (flags & M_RNOWAIT) == 0) {
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474 crit_enter();
475 if ((z = slgd->FreeOvZones) != NULL) {
476 KKASSERT(z->z_Magic == ZALLOC_OVSZ_MAGIC);
477 slgd->FreeOvZones = z->z_Next;
478 kmem_slab_free(z, z->z_ChunkSize); /* may block */
479 }
480 crit_exit();
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481 }
482
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483 /*
484 * Handle large allocations directly. There should not be very many of
485 * these so performance is not a big issue.
486 *
487 * Guarentee page alignment for allocations in multiples of PAGE_SIZE
488 */
46a3f46d 489 if (size >= ZoneLimit || (size & PAGE_MASK) == 0) {
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490 struct kmemusage *kup;
491
492 size = round_page(size);
493 chunk = kmem_slab_alloc(size, PAGE_SIZE, flags);
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494 if (chunk == NULL) {
495 logmemory(malloc, NULL, type, size, flags);
a108bf71 496 return(NULL);
f2b5daf9 497 }
a108bf71 498 flags &= ~M_ZERO; /* result already zero'd if M_ZERO was set */
8f1d5415 499 flags |= M_PASSIVE_ZERO;
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500 kup = btokup(chunk);
501 kup->ku_pagecnt = size / PAGE_SIZE;
bba6a44d 502 kup->ku_cpu = gd->gd_cpuid;
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503 crit_enter();
504 goto done;
505 }
506
507 /*
508 * Attempt to allocate out of an existing zone. First try the free list,
509 * then allocate out of unallocated space. If we find a good zone move
510 * it to the head of the list so later allocations find it quickly
511 * (we might have thousands of zones in the list).
512 *
513 * Note: zoneindex() will panic of size is too large.
514 */
515 zi = zoneindex(&size);
516 KKASSERT(zi < NZONES);
517 crit_enter();
518 if ((z = slgd->ZoneAry[zi]) != NULL) {
519 KKASSERT(z->z_NFree > 0);
520
521 /*
522 * Remove us from the ZoneAry[] when we become empty
523 */
524 if (--z->z_NFree == 0) {
525 slgd->ZoneAry[zi] = z->z_Next;
526 z->z_Next = NULL;
527 }
528
529 /*
530 * Locate a chunk in a free page. This attempts to localize
531 * reallocations into earlier pages without us having to sort
532 * the chunk list. A chunk may still overlap a page boundary.
533 */
534 while (z->z_FirstFreePg < ZonePageCount) {
535 if ((chunk = z->z_PageAry[z->z_FirstFreePg]) != NULL) {
536#ifdef DIAGNOSTIC
537 /*
538 * Diagnostic: c_Next is not total garbage.
539 */
540 KKASSERT(chunk->c_Next == NULL ||
541 ((intptr_t)chunk->c_Next & IN_SAME_PAGE_MASK) ==
542 ((intptr_t)chunk & IN_SAME_PAGE_MASK));
543#endif
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544#ifdef INVARIANTS
545 if ((uintptr_t)chunk < VM_MIN_KERNEL_ADDRESS)
a108bf71 546 panic("chunk %p FFPG %d/%d", chunk, z->z_FirstFreePg, ZonePageCount);
6ab8e1da 547 if (chunk->c_Next && (uintptr_t)chunk->c_Next < VM_MIN_KERNEL_ADDRESS)
a108bf71 548 panic("chunkNEXT %p %p FFPG %d/%d", chunk, chunk->c_Next, z->z_FirstFreePg, ZonePageCount);
10cc6608 549 chunk_mark_allocated(z, chunk);
6ab8e1da 550#endif
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551 z->z_PageAry[z->z_FirstFreePg] = chunk->c_Next;
552 goto done;
553 }
554 ++z->z_FirstFreePg;
555 }
556
557 /*
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558 * No chunks are available but NFree said we had some memory, so
559 * it must be available in the never-before-used-memory area
560 * governed by UIndex. The consequences are very serious if our zone
561 * got corrupted so we use an explicit panic rather then a KASSERT.
a108bf71 562 */
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563 if (z->z_UIndex + 1 != z->z_NMax)
564 z->z_UIndex = z->z_UIndex + 1;
565 else
566 z->z_UIndex = 0;
567 if (z->z_UIndex == z->z_UEndIndex)
568 panic("slaballoc: corrupted zone");
569 chunk = (SLChunk *)(z->z_BasePtr + z->z_UIndex * size);
8f1d5415 570 if ((z->z_Flags & SLZF_UNOTZEROD) == 0) {
6ab8e1da 571 flags &= ~M_ZERO;
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572 flags |= M_PASSIVE_ZERO;
573 }
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574#if defined(INVARIANTS)
575 chunk_mark_allocated(z, chunk);
576#endif
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577 goto done;
578 }
579
580 /*
581 * If all zones are exhausted we need to allocate a new zone for this
582 * index. Use M_ZERO to take advantage of pre-zerod pages. Also see
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583 * UAlloc use above in regards to M_ZERO. Note that when we are reusing
584 * a zone from the FreeZones list UAlloc'd data will not be zero'd, and
585 * we do not pre-zero it because we do not want to mess up the L1 cache.
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586 *
587 * At least one subsystem, the tty code (see CROUND) expects power-of-2
588 * allocations to be power-of-2 aligned. We maintain compatibility by
589 * adjusting the base offset below.
590 */
591 {
592 int off;
593
594 if ((z = slgd->FreeZones) != NULL) {
595 slgd->FreeZones = z->z_Next;
596 --slgd->NFreeZones;
597 bzero(z, sizeof(SLZone));
6ab8e1da 598 z->z_Flags |= SLZF_UNOTZEROD;
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MD
599 } else {
600 z = kmem_slab_alloc(ZoneSize, ZoneSize, flags|M_ZERO);
601 if (z == NULL)
602 goto fail;
603 }
604
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MD
605 /*
606 * How big is the base structure?
607 */
608#if defined(INVARIANTS)
609 /*
610 * Make room for z_Bitmap. An exact calculation is somewhat more
611 * complicated so don't make an exact calculation.
612 */
613 off = offsetof(SLZone, z_Bitmap[(ZoneSize / size + 31) / 32]);
614 bzero(z->z_Bitmap, (ZoneSize / size + 31) / 8);
615#else
616 off = sizeof(SLZone);
617#endif
618
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619 /*
620 * Guarentee power-of-2 alignment for power-of-2-sized chunks.
621 * Otherwise just 8-byte align the data.
622 */
623 if ((size | (size - 1)) + 1 == (size << 1))
10cc6608 624 off = (off + size - 1) & ~(size - 1);
a108bf71 625 else
10cc6608 626 off = (off + MIN_CHUNK_MASK) & ~MIN_CHUNK_MASK;
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MD
627 z->z_Magic = ZALLOC_SLAB_MAGIC;
628 z->z_ZoneIndex = zi;
629 z->z_NMax = (ZoneSize - off) / size;
630 z->z_NFree = z->z_NMax - 1;
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MD
631 z->z_BasePtr = (char *)z + off;
632 z->z_UIndex = z->z_UEndIndex = slgd->JunkIndex % z->z_NMax;
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633 z->z_ChunkSize = size;
634 z->z_FirstFreePg = ZonePageCount;
2db3b277 635 z->z_CpuGd = gd;
bba6a44d 636 z->z_Cpu = gd->gd_cpuid;
1c5ca4f3 637 chunk = (SLChunk *)(z->z_BasePtr + z->z_UIndex * size);
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638 z->z_Next = slgd->ZoneAry[zi];
639 slgd->ZoneAry[zi] = z;
8f1d5415 640 if ((z->z_Flags & SLZF_UNOTZEROD) == 0) {
6ab8e1da 641 flags &= ~M_ZERO; /* already zero'd */
8f1d5415
MD
642 flags |= M_PASSIVE_ZERO;
643 }
10cc6608
MD
644#if defined(INVARIANTS)
645 chunk_mark_allocated(z, chunk);
646#endif
1c5ca4f3
MD
647
648 /*
649 * Slide the base index for initial allocations out of the next
650 * zone we create so we do not over-weight the lower part of the
651 * cpu memory caches.
652 */
653 slgd->JunkIndex = (slgd->JunkIndex + ZALLOC_SLAB_SLIDE)
654 & (ZALLOC_MAX_ZONE_SIZE - 1);
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MD
655 }
656done:
bba6a44d
MD
657 ++type->ks_inuse[gd->gd_cpuid];
658 type->ks_memuse[gd->gd_cpuid] += size;
38e34349 659 type->ks_loosememuse += size; /* not MP synchronized */
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660 crit_exit();
661 if (flags & M_ZERO)
662 bzero(chunk, size);
bba6a44d 663#ifdef INVARIANTS
d2182dc1
MD
664 else if ((flags & (M_ZERO|M_PASSIVE_ZERO)) == 0) {
665 if (use_malloc_pattern) {
666 for (i = 0; i < size; i += sizeof(int)) {
667 *(int *)((char *)chunk + i) = -1;
668 }
669 }
bba6a44d 670 chunk->c_Next = (void *)-1; /* avoid accidental double-free check */
d2182dc1 671 }
bba6a44d 672#endif
f2b5daf9 673 logmemory(malloc, chunk, type, size, flags);
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MD
674 return(chunk);
675fail:
676 crit_exit();
f2b5daf9 677 logmemory(malloc, NULL, type, size, flags);
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678 return(NULL);
679}
680
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681/*
682 * kernel realloc. (SLAB ALLOCATOR) (MP SAFE)
683 *
684 * Generally speaking this routine is not called very often and we do
685 * not attempt to optimize it beyond reusing the same pointer if the
686 * new size fits within the chunking of the old pointer's zone.
687 */
a108bf71 688void *
8aca2bd4 689krealloc(void *ptr, unsigned long size, struct malloc_type *type, int flags)
a108bf71
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690{
691 SLZone *z;
692 void *nptr;
693 unsigned long osize;
694
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MD
695 KKASSERT((flags & M_ZERO) == 0); /* not supported */
696
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697 if (ptr == NULL || ptr == ZERO_LENGTH_PTR)
698 return(malloc(size, type, flags));
699 if (size == 0) {
700 free(ptr, type);
701 return(NULL);
702 }
703
704 /*
705 * Handle oversized allocations. XXX we really should require that a
706 * size be passed to free() instead of this nonsense.
707 */
708 {
709 struct kmemusage *kup;
710
711 kup = btokup(ptr);
712 if (kup->ku_pagecnt) {
713 osize = kup->ku_pagecnt << PAGE_SHIFT;
714 if (osize == round_page(size))
715 return(ptr);
716 if ((nptr = malloc(size, type, flags)) == NULL)
717 return(NULL);
718 bcopy(ptr, nptr, min(size, osize));
719 free(ptr, type);
720 return(nptr);
721 }
722 }
723
724 /*
725 * Get the original allocation's zone. If the new request winds up
726 * using the same chunk size we do not have to do anything.
727 */
728 z = (SLZone *)((uintptr_t)ptr & ~(uintptr_t)ZoneMask);
729 KKASSERT(z->z_Magic == ZALLOC_SLAB_MAGIC);
730
731 zoneindex(&size);
732 if (z->z_ChunkSize == size)
733 return(ptr);
734
735 /*
736 * Allocate memory for the new request size. Note that zoneindex has
737 * already adjusted the request size to the appropriate chunk size, which
738 * should optimize our bcopy(). Then copy and return the new pointer.
739 */
740 if ((nptr = malloc(size, type, flags)) == NULL)
741 return(NULL);
742 bcopy(ptr, nptr, min(size, z->z_ChunkSize));
743 free(ptr, type);
744 return(nptr);
745}
746
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MD
747/*
748 * Allocate a copy of the specified string.
749 *
750 * (MP SAFE) (MAY BLOCK)
751 */
1ac06773 752char *
59302080 753kstrdup(const char *str, struct malloc_type *type)
1ac06773
MD
754{
755 int zlen; /* length inclusive of terminating NUL */
756 char *nstr;
757
758 if (str == NULL)
759 return(NULL);
760 zlen = strlen(str) + 1;
761 nstr = malloc(zlen, type, M_WAITOK);
762 bcopy(str, nstr, zlen);
763 return(nstr);
764}
765
1d712609 766#ifdef SMP
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767/*
768 * free() (SLAB ALLOCATOR)
769 *
bba6a44d 770 * Free the specified chunk of memory.
a108bf71
MD
771 */
772static
773void
774free_remote(void *ptr)
775{
f2b5daf9 776 logmemory(free_remote, ptr, *(struct malloc_type **)ptr, -1, 0);
a108bf71
MD
777 free(ptr, *(struct malloc_type **)ptr);
778}
779
1d712609
MD
780#endif
781
38e34349 782/*
5b287bba 783 * free (SLAB ALLOCATOR)
38e34349
MD
784 *
785 * Free a memory block previously allocated by malloc. Note that we do not
786 * attempt to uplodate ks_loosememuse as MP races could prevent us from
787 * checking memory limits in malloc.
5b287bba
MD
788 *
789 * MPSAFE
38e34349 790 */
a108bf71 791void
8aca2bd4 792kfree(void *ptr, struct malloc_type *type)
a108bf71
MD
793{
794 SLZone *z;
795 SLChunk *chunk;
796 SLGlobalData *slgd;
bba6a44d 797 struct globaldata *gd;
a108bf71
MD
798 int pgno;
799
b68ad50c 800 logmemory_quick(free_beg);
bba6a44d
MD
801 gd = mycpu;
802 slgd = &gd->gd_slab;
a108bf71 803
d39911d9
JS
804 if (ptr == NULL)
805 panic("trying to free NULL pointer");
806
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MD
807 /*
808 * Handle special 0-byte allocations
809 */
f2b5daf9
MD
810 if (ptr == ZERO_LENGTH_PTR) {
811 logmemory(free_zero, ptr, type, -1, 0);
b68ad50c 812 logmemory_quick(free_end);
a108bf71 813 return;
f2b5daf9 814 }
a108bf71
MD
815
816 /*
817 * Handle oversized allocations. XXX we really should require that a
818 * size be passed to free() instead of this nonsense.
bba6a44d
MD
819 *
820 * This code is never called via an ipi.
a108bf71
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821 */
822 {
823 struct kmemusage *kup;
824 unsigned long size;
825
826 kup = btokup(ptr);
827 if (kup->ku_pagecnt) {
828 size = kup->ku_pagecnt << PAGE_SHIFT;
829 kup->ku_pagecnt = 0;
a108bf71
MD
830#ifdef INVARIANTS
831 KKASSERT(sizeof(weirdary) <= size);
832 bcopy(weirdary, ptr, sizeof(weirdary));
833#endif
bba6a44d
MD
834 /*
835 * note: we always adjust our cpu's slot, not the originating
836 * cpu (kup->ku_cpuid). The statistics are in aggregate.
81f5fc99
MD
837 *
838 * note: XXX we have still inherited the interrupts-can't-block
839 * assumption. An interrupt thread does not bump
840 * gd_intr_nesting_level so check TDF_INTTHREAD. This is
841 * primarily until we can fix softupdate's assumptions about free().
bba6a44d
MD
842 */
843 crit_enter();
844 --type->ks_inuse[gd->gd_cpuid];
845 type->ks_memuse[gd->gd_cpuid] -= size;
81f5fc99 846 if (mycpu->gd_intr_nesting_level || (gd->gd_curthread->td_flags & TDF_INTTHREAD)) {
f2b5daf9 847 logmemory(free_ovsz_delayed, ptr, type, size, 0);
46a3f46d
MD
848 z = (SLZone *)ptr;
849 z->z_Magic = ZALLOC_OVSZ_MAGIC;
850 z->z_Next = slgd->FreeOvZones;
851 z->z_ChunkSize = size;
852 slgd->FreeOvZones = z;
853 crit_exit();
854 } else {
bba6a44d 855 crit_exit();
f2b5daf9 856 logmemory(free_ovsz, ptr, type, size, 0);
46a3f46d
MD
857 kmem_slab_free(ptr, size); /* may block */
858 }
b68ad50c 859 logmemory_quick(free_end);
a108bf71
MD
860 return;
861 }
862 }
863
864 /*
865 * Zone case. Figure out the zone based on the fact that it is
866 * ZoneSize aligned.
867 */
868 z = (SLZone *)((uintptr_t)ptr & ~(uintptr_t)ZoneMask);
869 KKASSERT(z->z_Magic == ZALLOC_SLAB_MAGIC);
870
871 /*
872 * If we do not own the zone then forward the request to the
4c9f5a7f
MD
873 * cpu that does. Since the timing is non-critical, a passive
874 * message is sent.
a108bf71 875 */
2db3b277 876 if (z->z_CpuGd != gd) {
a108bf71 877 *(struct malloc_type **)ptr = type;
75c7ffea 878#ifdef SMP
f2b5daf9 879 logmemory(free_request, ptr, type, z->z_ChunkSize, 0);
4c9f5a7f 880 lwkt_send_ipiq_passive(z->z_CpuGd, free_remote, ptr);
75c7ffea
MD
881#else
882 panic("Corrupt SLZone");
883#endif
b68ad50c 884 logmemory_quick(free_end);
a108bf71
MD
885 return;
886 }
887
f2b5daf9
MD
888 logmemory(free_chunk, ptr, type, z->z_ChunkSize, 0);
889
a108bf71
MD
890 if (type->ks_magic != M_MAGIC)
891 panic("free: malloc type lacks magic");
892
893 crit_enter();
894 pgno = ((char *)ptr - (char *)z) >> PAGE_SHIFT;
895 chunk = ptr;
896
bba6a44d 897#ifdef INVARIANTS
a108bf71 898 /*
bba6a44d
MD
899 * Attempt to detect a double-free. To reduce overhead we only check
900 * if there appears to be link pointer at the base of the data.
a108bf71
MD
901 */
902 if (((intptr_t)chunk->c_Next - (intptr_t)z) >> PAGE_SHIFT == pgno) {
903 SLChunk *scan;
904 for (scan = z->z_PageAry[pgno]; scan; scan = scan->c_Next) {
905 if (scan == chunk)
906 panic("Double free at %p", chunk);
907 }
908 }
10cc6608 909 chunk_mark_free(z, chunk);
a108bf71
MD
910#endif
911
912 /*
913 * Put weird data into the memory to detect modifications after freeing,
914 * illegal pointer use after freeing (we should fault on the odd address),
915 * and so forth. XXX needs more work, see the old malloc code.
916 */
917#ifdef INVARIANTS
918 if (z->z_ChunkSize < sizeof(weirdary))
919 bcopy(weirdary, chunk, z->z_ChunkSize);
920 else
921 bcopy(weirdary, chunk, sizeof(weirdary));
922#endif
923
924 /*
925 * Add this free non-zero'd chunk to a linked list for reuse, adjust
926 * z_FirstFreePg.
927 */
6ab8e1da
MD
928#ifdef INVARIANTS
929 if ((uintptr_t)chunk < VM_MIN_KERNEL_ADDRESS)
fc92d4aa 930 panic("BADFREE %p", chunk);
a108bf71
MD
931#endif
932 chunk->c_Next = z->z_PageAry[pgno];
933 z->z_PageAry[pgno] = chunk;
6ab8e1da
MD
934#ifdef INVARIANTS
935 if (chunk->c_Next && (uintptr_t)chunk->c_Next < VM_MIN_KERNEL_ADDRESS)
a108bf71 936 panic("BADFREE2");
6ab8e1da 937#endif
a108bf71
MD
938 if (z->z_FirstFreePg > pgno)
939 z->z_FirstFreePg = pgno;
940
941 /*
942 * Bump the number of free chunks. If it becomes non-zero the zone
943 * must be added back onto the appropriate list.
944 */
945 if (z->z_NFree++ == 0) {
946 z->z_Next = slgd->ZoneAry[z->z_ZoneIndex];
947 slgd->ZoneAry[z->z_ZoneIndex] = z;
948 }
949
bba6a44d
MD
950 --type->ks_inuse[z->z_Cpu];
951 type->ks_memuse[z->z_Cpu] -= z->z_ChunkSize;
a108bf71
MD
952
953 /*
954 * If the zone becomes totally free, and there are other zones we
a7cf0021
MD
955 * can allocate from, move this zone to the FreeZones list. Since
956 * this code can be called from an IPI callback, do *NOT* try to mess
957 * with kernel_map here. Hysteresis will be performed at malloc() time.
a108bf71
MD
958 */
959 if (z->z_NFree == z->z_NMax &&
960 (z->z_Next || slgd->ZoneAry[z->z_ZoneIndex] != z)
961 ) {
962 SLZone **pz;
963
964 for (pz = &slgd->ZoneAry[z->z_ZoneIndex]; z != *pz; pz = &(*pz)->z_Next)
965 ;
966 *pz = z->z_Next;
967 z->z_Magic = -1;
a7cf0021
MD
968 z->z_Next = slgd->FreeZones;
969 slgd->FreeZones = z;
970 ++slgd->NFreeZones;
a108bf71 971 }
b68ad50c 972 logmemory_quick(free_end);
a108bf71
MD
973 crit_exit();
974}
975
10cc6608
MD
976#if defined(INVARIANTS)
977/*
978 * Helper routines for sanity checks
979 */
980static
981void
982chunk_mark_allocated(SLZone *z, void *chunk)
983{
984 int bitdex = ((char *)chunk - (char *)z->z_BasePtr) / z->z_ChunkSize;
985 __uint32_t *bitptr;
986
987 KASSERT(bitdex >= 0 && bitdex < z->z_NMax, ("memory chunk %p bit index %d is illegal", chunk, bitdex));
988 bitptr = &z->z_Bitmap[bitdex >> 5];
989 bitdex &= 31;
990 KASSERT((*bitptr & (1 << bitdex)) == 0, ("memory chunk %p is already allocated!", chunk));
991 *bitptr |= 1 << bitdex;
992}
993
994static
995void
996chunk_mark_free(SLZone *z, void *chunk)
997{
998 int bitdex = ((char *)chunk - (char *)z->z_BasePtr) / z->z_ChunkSize;
999 __uint32_t *bitptr;
1000
1001 KASSERT(bitdex >= 0 && bitdex < z->z_NMax, ("memory chunk %p bit index %d is illegal!", chunk, bitdex));
1002 bitptr = &z->z_Bitmap[bitdex >> 5];
1003 bitdex &= 31;
1004 KASSERT((*bitptr & (1 << bitdex)) != 0, ("memory chunk %p is already free!", chunk));
1005 *bitptr &= ~(1 << bitdex);
1006}
1007
1008#endif
1009
8aca2bd4
MD
1010#if !defined(KMALLOC_ONLY)
1011/*
1012 * Compatibility code for old libc-hostile function names
1013 */
1014
1015void *
1016malloc(unsigned long size, struct malloc_type *type, int flags)
1017{
1018 return(kmalloc(size, type, flags));
1019}
1020
1021void *
1022realloc(void *ptr, unsigned long size, struct malloc_type *type, int flags)
1023{
1024 return(krealloc(ptr, size, type, flags));
1025}
1026
1027void
1028free(void *ptr, struct malloc_type *type)
1029{
1030 kfree(ptr, type);
1031}
1032
1033#endif
1034
a108bf71 1035/*
5b287bba 1036 * kmem_slab_alloc()
a108bf71
MD
1037 *
1038 * Directly allocate and wire kernel memory in PAGE_SIZE chunks with the
1039 * specified alignment. M_* flags are expected in the flags field.
1040 *
1041 * Alignment must be a multiple of PAGE_SIZE.
1042 *
1043 * NOTE! XXX For the moment we use vm_map_entry_reserve/release(),
1044 * but when we move zalloc() over to use this function as its backend
1045 * we will have to switch to kreserve/krelease and call reserve(0)
1046 * after the new space is made available.
dc1fd4b3
MD
1047 *
1048 * Interrupt code which has preempted other code is not allowed to
c397c465
MD
1049 * use PQ_CACHE pages. However, if an interrupt thread is run
1050 * non-preemptively or blocks and then runs non-preemptively, then
1051 * it is free to use PQ_CACHE pages.
38e34349
MD
1052 *
1053 * This routine will currently obtain the BGL.
5b287bba
MD
1054 *
1055 * MPALMOSTSAFE - acquires mplock
a108bf71
MD
1056 */
1057static void *
1058kmem_slab_alloc(vm_size_t size, vm_offset_t align, int flags)
1059{
1060 vm_size_t i;
1061 vm_offset_t addr;
1062 vm_offset_t offset;
1de1e800 1063 int count, vmflags, base_vmflags;
dc1fd4b3 1064 thread_t td;
a108bf71
MD
1065 vm_map_t map = kernel_map;
1066
1067 size = round_page(size);
1068 addr = vm_map_min(map);
1069
1070 /*
5c39c498
MD
1071 * Reserve properly aligned space from kernel_map. RNOWAIT allocations
1072 * cannot block.
a108bf71 1073 */
5c39c498
MD
1074 if (flags & M_RNOWAIT) {
1075 if (try_mplock() == 0)
1076 return(NULL);
1077 } else {
1078 get_mplock();
1079 }
a108bf71
MD
1080 count = vm_map_entry_reserve(MAP_RESERVE_COUNT);
1081 crit_enter();
1082 vm_map_lock(map);
1083 if (vm_map_findspace(map, vm_map_min(map), size, align, &addr)) {
1084 vm_map_unlock(map);
8cb2bf45 1085 if ((flags & M_NULLOK) == 0)
a108bf71
MD
1086 panic("kmem_slab_alloc(): kernel_map ran out of space!");
1087 crit_exit();
1088 vm_map_entry_release(count);
38e34349 1089 rel_mplock();
a108bf71
MD
1090 return(NULL);
1091 }
1092 offset = addr - VM_MIN_KERNEL_ADDRESS;
1093 vm_object_reference(kernel_object);
1094 vm_map_insert(map, &count,
1095 kernel_object, offset, addr, addr + size,
1096 VM_PROT_ALL, VM_PROT_ALL, 0);
1097
dc1fd4b3 1098 td = curthread;
dc1fd4b3 1099
1de1e800
JS
1100 base_vmflags = 0;
1101 if (flags & M_ZERO)
1102 base_vmflags |= VM_ALLOC_ZERO;
1103 if (flags & M_USE_RESERVE)
1104 base_vmflags |= VM_ALLOC_SYSTEM;
1105 if (flags & M_USE_INTERRUPT_RESERVE)
1106 base_vmflags |= VM_ALLOC_INTERRUPT;
1107 if ((flags & (M_RNOWAIT|M_WAITOK)) == 0)
1108 panic("kmem_slab_alloc: bad flags %08x (%p)", flags, ((int **)&size)[-1]);
1109
1110
a108bf71
MD
1111 /*
1112 * Allocate the pages. Do not mess with the PG_ZERO flag yet.
1113 */
1114 for (i = 0; i < size; i += PAGE_SIZE) {
1115 vm_page_t m;
1116 vm_pindex_t idx = OFF_TO_IDX(offset + i);
fe1e98d0
MD
1117
1118 /*
c397c465
MD
1119 * VM_ALLOC_NORMAL can only be set if we are not preempting.
1120 *
1121 * VM_ALLOC_SYSTEM is automatically set if we are preempting and
1122 * M_WAITOK was specified as an alternative (i.e. M_USE_RESERVE is
1123 * implied in this case), though I'm sure if we really need to do
1124 * that.
fe1e98d0 1125 */
1de1e800 1126 vmflags = base_vmflags;
c397c465 1127 if (flags & M_WAITOK) {
1de1e800 1128 if (td->td_preempted)
fe1e98d0 1129 vmflags |= VM_ALLOC_SYSTEM;
1de1e800 1130 else
dc1fd4b3 1131 vmflags |= VM_ALLOC_NORMAL;
dc1fd4b3 1132 }
a108bf71 1133
dc1fd4b3
MD
1134 m = vm_page_alloc(kernel_object, idx, vmflags);
1135
1136 /*
1137 * If the allocation failed we either return NULL or we retry.
1138 *
c397c465
MD
1139 * If M_WAITOK is specified we wait for more memory and retry.
1140 * If M_WAITOK is specified from a preemption we yield instead of
1141 * wait. Livelock will not occur because the interrupt thread
1142 * will not be preempting anyone the second time around after the
1143 * yield.
dc1fd4b3 1144 */
a108bf71 1145 if (m == NULL) {
c397c465 1146 if (flags & M_WAITOK) {
fe1e98d0 1147 if (td->td_preempted) {
dc1fd4b3
MD
1148 vm_map_unlock(map);
1149 lwkt_yield();
1150 vm_map_lock(map);
1151 } else {
dc1fd4b3
MD
1152 vm_map_unlock(map);
1153 vm_wait();
1154 vm_map_lock(map);
1155 }
a108bf71
MD
1156 i -= PAGE_SIZE; /* retry */
1157 continue;
1158 }
dc1fd4b3
MD
1159
1160 /*
1161 * We were unable to recover, cleanup and return NULL
1162 */
a108bf71
MD
1163 while (i != 0) {
1164 i -= PAGE_SIZE;
1165 m = vm_page_lookup(kernel_object, OFF_TO_IDX(offset + i));
1166 vm_page_free(m);
1167 }
1168 vm_map_delete(map, addr, addr + size, &count);
1169 vm_map_unlock(map);
1170 crit_exit();
1171 vm_map_entry_release(count);
38e34349 1172 rel_mplock();
a108bf71
MD
1173 return(NULL);
1174 }
1175 }
1176
1177 /*
dc1fd4b3
MD
1178 * Success!
1179 *
a108bf71
MD
1180 * Mark the map entry as non-pageable using a routine that allows us to
1181 * populate the underlying pages.
1182 */
1183 vm_map_set_wired_quick(map, addr, size, &count);
1184 crit_exit();
1185
1186 /*
1187 * Enter the pages into the pmap and deal with PG_ZERO and M_ZERO.
1188 */
1189 for (i = 0; i < size; i += PAGE_SIZE) {
1190 vm_page_t m;
1191
1192 m = vm_page_lookup(kernel_object, OFF_TO_IDX(offset + i));
1193 m->valid = VM_PAGE_BITS_ALL;
1194 vm_page_wire(m);
1195 vm_page_wakeup(m);
1196 pmap_enter(kernel_pmap, addr + i, m, VM_PROT_ALL, 1);
1197 if ((m->flags & PG_ZERO) == 0 && (flags & M_ZERO))
1198 bzero((char *)addr + i, PAGE_SIZE);
1199 vm_page_flag_clear(m, PG_ZERO);
1200 vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE | PG_REFERENCED);
1201 }
1202 vm_map_unlock(map);
1203 vm_map_entry_release(count);
38e34349 1204 rel_mplock();
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1205 return((void *)addr);
1206}
1207
38e34349 1208/*
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1209 * kmem_slab_free()
1210 *
1211 * MPALMOSTSAFE - acquires mplock
38e34349 1212 */
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1213static void
1214kmem_slab_free(void *ptr, vm_size_t size)
1215{
38e34349 1216 get_mplock();
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1217 crit_enter();
1218 vm_map_remove(kernel_map, (vm_offset_t)ptr, (vm_offset_t)ptr + size);
1219 crit_exit();
38e34349 1220 rel_mplock();
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1221}
1222