BSD 4.4 Lite Kernel Sources

1 files changed, 381 insertions, 0 deletions

diff --git a/sys/kern/kern_malloc.c b/sys/kern/kern_malloc.c
new file mode 100644
index 000000000000..c6276bc73cf4
--- /dev/null
+++ b/sys/kern/kern_malloc.c
@@ -0,0 +1,381 @@
+/*
+ * 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 first word of the structure is used to hold the list
+ * pointer for free objects. However, when running with diagnostics,
+ * we use the third and fourth fields, so as to catch modifications
+ * in the most commonly trashed first two words.
+ */
+struct freelist {
+	long	spare0;
+	short	type;
+	long	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
+	long *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 = (long *)&cp[copysize];
+			for (lp = (long *)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 of object 0x%x size %d %s %s (invalid addr 0x%x)\n",
+			"Data modified on freelist: word 2.5", va, size,
+			"previous type", savedtype, kbp->kb_next);
+		kbp->kb_next = NULL;
+	}
+#if BYTE_ORDER == BIG_ENDIAN
+	freep->type = WEIRD_ADDR >> 16;
+#endif
+#if BYTE_ORDER == LITTLE_ENDIAN
+	freep->type = (short)WEIRD_ADDR;
+#endif
+	if (((long)(&freep->next)) & 0x2)
+		freep->next = (caddr_t)((WEIRD_ADDR >> 16)|(WEIRD_ADDR << 16));
+	else
+		freep->next = (caddr_t)WEIRD_ADDR;
+	end = (long *)&va[copysize];
+	for (lp = (long *)va; lp < end; lp++) {
+		if (*lp == WEIRD_ADDR)
+			continue;
+		printf("%s %d of object 0x%x size %d %s %s (0x%x != 0x%x)\n",
+			"Data modified on freelist: word", lp - (long *)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;
+	long *end, *lp, 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 0x%x\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 = (long *)&((caddr_t)addr)[copysize];
+	for (lp = (long *)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
+	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
+}