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-rw-r--r--sys/kern/kern_malloc.c396
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diff --git a/sys/kern/kern_malloc.c b/sys/kern/kern_malloc.c
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+/* $NetBSD: kern_malloc.c,v 1.11 1995/05/01 22:39:11 cgd Exp $ */
+
+/*
+ * Copyright (c) 1987, 1991, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * @(#)kern_malloc.c 8.3 (Berkeley) 1/4/94
+ */
+
+#include <sys/param.h>
+#include <sys/proc.h>
+#include <sys/map.h>
+#include <sys/kernel.h>
+#include <sys/malloc.h>
+
+#include <vm/vm.h>
+#include <vm/vm_kern.h>
+
+struct kmembuckets bucket[MINBUCKET + 16];
+struct kmemstats kmemstats[M_LAST];
+struct kmemusage *kmemusage;
+char *kmembase, *kmemlimit;
+char *memname[] = INITKMEMNAMES;
+
+#ifdef DIAGNOSTIC
+/*
+ * This structure provides a set of masks to catch unaligned frees.
+ */
+long addrmask[] = { 0,
+ 0x00000001, 0x00000003, 0x00000007, 0x0000000f,
+ 0x0000001f, 0x0000003f, 0x0000007f, 0x000000ff,
+ 0x000001ff, 0x000003ff, 0x000007ff, 0x00000fff,
+ 0x00001fff, 0x00003fff, 0x00007fff, 0x0000ffff,
+};
+
+/*
+ * The WEIRD_ADDR is used as known text to copy into free objects so
+ * that modifications after frees can be detected.
+ */
+#define WEIRD_ADDR 0xdeadbeef
+#define MAX_COPY 32
+
+/*
+ * Normally the freelist structure is used only to hold the list pointer
+ * for free objects. However, when running with diagnostics, the first
+ * 8 bytes of the structure is unused except for diagnostic information,
+ * and the free list pointer is at offst 8 in the structure. Since the
+ * first 8 bytes is the portion of the structure most often modified, this
+ * helps to detect memory reuse problems and avoid free list corruption.
+ */
+struct freelist {
+ int32_t spare0;
+ int16_t type;
+ int16_t spare1;
+ caddr_t next;
+};
+#else /* !DIAGNOSTIC */
+struct freelist {
+ caddr_t next;
+};
+#endif /* DIAGNOSTIC */
+
+/*
+ * Allocate a block of memory
+ */
+void *
+malloc(size, type, flags)
+ unsigned long size;
+ int type, flags;
+{
+ register struct kmembuckets *kbp;
+ register struct kmemusage *kup;
+ register struct freelist *freep;
+ long indx, npg, allocsize;
+ int s;
+ caddr_t va, cp, savedlist;
+#ifdef DIAGNOSTIC
+ int32_t *end, *lp;
+ int copysize;
+ char *savedtype;
+#endif
+#ifdef KMEMSTATS
+ register struct kmemstats *ksp = &kmemstats[type];
+
+ if (((unsigned long)type) > M_LAST)
+ panic("malloc - bogus type");
+#endif
+ indx = BUCKETINDX(size);
+ kbp = &bucket[indx];
+ s = splimp();
+#ifdef KMEMSTATS
+ while (ksp->ks_memuse >= ksp->ks_limit) {
+ if (flags & M_NOWAIT) {
+ splx(s);
+ return ((void *) NULL);
+ }
+ if (ksp->ks_limblocks < 65535)
+ ksp->ks_limblocks++;
+ tsleep((caddr_t)ksp, PSWP+2, memname[type], 0);
+ }
+ ksp->ks_size |= 1 << indx;
+#endif
+#ifdef DIAGNOSTIC
+ copysize = 1 << indx < MAX_COPY ? 1 << indx : MAX_COPY;
+#endif
+ if (kbp->kb_next == NULL) {
+ kbp->kb_last = NULL;
+ if (size > MAXALLOCSAVE)
+ allocsize = roundup(size, CLBYTES);
+ else
+ allocsize = 1 << indx;
+ npg = clrnd(btoc(allocsize));
+ va = (caddr_t) kmem_malloc(kmem_map, (vm_size_t)ctob(npg),
+ !(flags & M_NOWAIT));
+ if (va == NULL) {
+ splx(s);
+ return ((void *) NULL);
+ }
+#ifdef KMEMSTATS
+ kbp->kb_total += kbp->kb_elmpercl;
+#endif
+ kup = btokup(va);
+ kup->ku_indx = indx;
+ if (allocsize > MAXALLOCSAVE) {
+ if (npg > 65535)
+ panic("malloc: allocation too large");
+ kup->ku_pagecnt = npg;
+#ifdef KMEMSTATS
+ ksp->ks_memuse += allocsize;
+#endif
+ goto out;
+ }
+#ifdef KMEMSTATS
+ kup->ku_freecnt = kbp->kb_elmpercl;
+ kbp->kb_totalfree += kbp->kb_elmpercl;
+#endif
+ /*
+ * Just in case we blocked while allocating memory,
+ * and someone else also allocated memory for this
+ * bucket, don't assume the list is still empty.
+ */
+ savedlist = kbp->kb_next;
+ kbp->kb_next = cp = va + (npg * NBPG) - allocsize;
+ for (;;) {
+ freep = (struct freelist *)cp;
+#ifdef DIAGNOSTIC
+ /*
+ * Copy in known text to detect modification
+ * after freeing.
+ */
+ end = (int32_t *)&cp[copysize];
+ for (lp = (int32_t *)cp; lp < end; lp++)
+ *lp = WEIRD_ADDR;
+ freep->type = M_FREE;
+#endif /* DIAGNOSTIC */
+ if (cp <= va)
+ break;
+ cp -= allocsize;
+ freep->next = cp;
+ }
+ freep->next = savedlist;
+ if (kbp->kb_last == NULL)
+ kbp->kb_last = (caddr_t)freep;
+ }
+ va = kbp->kb_next;
+ kbp->kb_next = ((struct freelist *)va)->next;
+#ifdef DIAGNOSTIC
+ freep = (struct freelist *)va;
+ savedtype = (unsigned)freep->type < M_LAST ?
+ memname[freep->type] : "???";
+ if (kbp->kb_next &&
+ !kernacc(kbp->kb_next, sizeof(struct freelist), 0)) {
+ printf("%s %d of object %p size %d %s %s (invalid addr %p)\n",
+ "Data modified on freelist: word",
+ (int32_t *)&kbp->kb_next - (int32_t *)kbp, va, size,
+ "previous type", savedtype, kbp->kb_next);
+ kbp->kb_next = NULL;
+ }
+
+ /* Fill the fields that we've used with WEIRD_ADDR */
+#if BYTE_ORDER == BIG_ENDIAN
+ freep->type = WEIRD_ADDR >> 16;
+#endif
+#if BYTE_ORDER == LITTLE_ENDIAN
+ freep->type = (short)WEIRD_ADDR;
+#endif
+ end = (int32_t *)&freep->next +
+ (sizeof(freep->next) / sizeof(int32_t));
+ for (lp = (int32_t *)&freep->next; lp < end; lp++)
+ *lp = WEIRD_ADDR;
+
+ /* and check that the data hasn't been modified. */
+ end = (int32_t *)&va[copysize];
+ for (lp = (int32_t *)va; lp < end; lp++) {
+ if (*lp == WEIRD_ADDR)
+ continue;
+ printf("%s %d of object %p size %d %s %s (%p != %p)\n",
+ "Data modified on freelist: word", lp - (int32_t *)va,
+ va, size, "previous type", savedtype, *lp, WEIRD_ADDR);
+ break;
+ }
+
+ freep->spare0 = 0;
+#endif /* DIAGNOSTIC */
+#ifdef KMEMSTATS
+ kup = btokup(va);
+ if (kup->ku_indx != indx)
+ panic("malloc: wrong bucket");
+ if (kup->ku_freecnt == 0)
+ panic("malloc: lost data");
+ kup->ku_freecnt--;
+ kbp->kb_totalfree--;
+ ksp->ks_memuse += 1 << indx;
+out:
+ kbp->kb_calls++;
+ ksp->ks_inuse++;
+ ksp->ks_calls++;
+ if (ksp->ks_memuse > ksp->ks_maxused)
+ ksp->ks_maxused = ksp->ks_memuse;
+#else
+out:
+#endif
+ splx(s);
+ return ((void *) va);
+}
+
+/*
+ * Free a block of memory allocated by malloc.
+ */
+void
+free(addr, type)
+ void *addr;
+ int type;
+{
+ register struct kmembuckets *kbp;
+ register struct kmemusage *kup;
+ register struct freelist *freep;
+ long size;
+ int s;
+#ifdef DIAGNOSTIC
+ caddr_t cp;
+ int32_t *end, *lp;
+ long alloc, copysize;
+#endif
+#ifdef KMEMSTATS
+ register struct kmemstats *ksp = &kmemstats[type];
+#endif
+
+ kup = btokup(addr);
+ size = 1 << kup->ku_indx;
+ kbp = &bucket[kup->ku_indx];
+ s = splimp();
+#ifdef DIAGNOSTIC
+ /*
+ * Check for returns of data that do not point to the
+ * beginning of the allocation.
+ */
+ if (size > NBPG * CLSIZE)
+ alloc = addrmask[BUCKETINDX(NBPG * CLSIZE)];
+ else
+ alloc = addrmask[kup->ku_indx];
+ if (((u_long)addr & alloc) != 0)
+ panic("free: unaligned addr 0x%x, size %d, type %s, mask %d\n",
+ addr, size, memname[type], alloc);
+#endif /* DIAGNOSTIC */
+ if (size > MAXALLOCSAVE) {
+ kmem_free(kmem_map, (vm_offset_t)addr, ctob(kup->ku_pagecnt));
+#ifdef KMEMSTATS
+ size = kup->ku_pagecnt << PGSHIFT;
+ ksp->ks_memuse -= size;
+ kup->ku_indx = 0;
+ kup->ku_pagecnt = 0;
+ if (ksp->ks_memuse + size >= ksp->ks_limit &&
+ ksp->ks_memuse < ksp->ks_limit)
+ wakeup((caddr_t)ksp);
+ ksp->ks_inuse--;
+ kbp->kb_total -= 1;
+#endif
+ splx(s);
+ return;
+ }
+ freep = (struct freelist *)addr;
+#ifdef DIAGNOSTIC
+ /*
+ * Check for multiple frees. Use a quick check to see if
+ * it looks free before laboriously searching the freelist.
+ */
+ if (freep->spare0 == WEIRD_ADDR) {
+ for (cp = kbp->kb_next; cp; cp = *(caddr_t *)cp) {
+ if (addr != cp)
+ continue;
+ printf("multiply freed item %p\n", addr);
+ panic("free: duplicated free");
+ }
+ }
+ /*
+ * Copy in known text to detect modification after freeing
+ * and to make it look free. Also, save the type being freed
+ * so we can list likely culprit if modification is detected
+ * when the object is reallocated.
+ */
+ copysize = size < MAX_COPY ? size : MAX_COPY;
+ end = (int32_t *)&((caddr_t)addr)[copysize];
+ for (lp = (int32_t *)addr; lp < end; lp++)
+ *lp = WEIRD_ADDR;
+ freep->type = type;
+#endif /* DIAGNOSTIC */
+#ifdef KMEMSTATS
+ kup->ku_freecnt++;
+ if (kup->ku_freecnt >= kbp->kb_elmpercl)
+ if (kup->ku_freecnt > kbp->kb_elmpercl)
+ panic("free: multiple frees");
+ else if (kbp->kb_totalfree > kbp->kb_highwat)
+ kbp->kb_couldfree++;
+ kbp->kb_totalfree++;
+ ksp->ks_memuse -= size;
+ if (ksp->ks_memuse + size >= ksp->ks_limit &&
+ ksp->ks_memuse < ksp->ks_limit)
+ wakeup((caddr_t)ksp);
+ ksp->ks_inuse--;
+#endif
+ if (kbp->kb_next == NULL)
+ kbp->kb_next = addr;
+ else
+ ((struct freelist *)kbp->kb_last)->next = addr;
+ freep->next = NULL;
+ kbp->kb_last = addr;
+ splx(s);
+}
+
+/*
+ * Initialize the kernel memory allocator
+ */
+kmeminit()
+{
+ register long indx;
+ int npg;
+
+#if ((MAXALLOCSAVE & (MAXALLOCSAVE - 1)) != 0)
+ ERROR!_kmeminit:_MAXALLOCSAVE_not_power_of_2
+#endif
+#if (MAXALLOCSAVE > MINALLOCSIZE * 32768)
+ ERROR!_kmeminit:_MAXALLOCSAVE_too_big
+#endif
+#if (MAXALLOCSAVE < CLBYTES)
+ ERROR!_kmeminit:_MAXALLOCSAVE_too_small
+#endif
+
+ if (sizeof(struct freelist) > (1 << MINBUCKET))
+ panic("minbucket too small/struct freelist too big");
+
+ npg = VM_KMEM_SIZE/ NBPG;
+ kmemusage = (struct kmemusage *) kmem_alloc(kernel_map,
+ (vm_size_t)(npg * sizeof(struct kmemusage)));
+ kmem_map = kmem_suballoc(kernel_map, (vm_offset_t *)&kmembase,
+ (vm_offset_t *)&kmemlimit, (vm_size_t)(npg * NBPG), FALSE);
+#ifdef KMEMSTATS
+ for (indx = 0; indx < MINBUCKET + 16; indx++) {
+ if (1 << indx >= CLBYTES)
+ bucket[indx].kb_elmpercl = 1;
+ else
+ bucket[indx].kb_elmpercl = CLBYTES / (1 << indx);
+ bucket[indx].kb_highwat = 5 * bucket[indx].kb_elmpercl;
+ }
+ for (indx = 0; indx < M_LAST; indx++)
+ kmemstats[indx].ks_limit = npg * NBPG * 6 / 10;
+#endif
+}