098a0a97ed
Submitted by: Loren James Rittle <rittle@latour.rsch.comm.mot.com>
1145 lines
25 KiB
C
1145 lines
25 KiB
C
/*
|
|
* ----------------------------------------------------------------------------
|
|
* "THE BEER-WARE LICENSE" (Revision 42):
|
|
* <phk@FreeBSD.ORG> wrote this file. As long as you retain this notice you
|
|
* can do whatever you want with this stuff. If we meet some day, and you think
|
|
* this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
|
|
* ----------------------------------------------------------------------------
|
|
*
|
|
* $FreeBSD$
|
|
*
|
|
*/
|
|
|
|
/*
|
|
* Defining EXTRA_SANITY will enable extra checks which are related
|
|
* to internal conditions and consistency in malloc.c. This has a
|
|
* noticeable runtime performance hit, and generally will not do you
|
|
* any good unless you fiddle with the internals of malloc or want
|
|
* to catch random pointer corruption as early as possible.
|
|
*/
|
|
#ifndef MALLOC_EXTRA_SANITY
|
|
#undef MALLOC_EXTRA_SANITY
|
|
#endif
|
|
|
|
/*
|
|
* What to use for Junk. This is the byte value we use to fill with
|
|
* when the 'J' option is enabled.
|
|
*/
|
|
#define SOME_JUNK 0xd0 /* as in "Duh" :-) */
|
|
|
|
/*
|
|
* The basic parameters you can tweak.
|
|
*
|
|
* malloc_pageshift pagesize = 1 << malloc_pageshift
|
|
* It's probably best if this is the native
|
|
* page size, but it doesn't have to be.
|
|
*
|
|
* malloc_minsize minimum size of an allocation in bytes.
|
|
* If this is too small it's too much work
|
|
* to manage them. This is also the smallest
|
|
* unit of alignment used for the storage
|
|
* returned by malloc/realloc.
|
|
*
|
|
*/
|
|
|
|
#include "namespace.h"
|
|
#if defined(__FreeBSD__)
|
|
# if defined(__i386__)
|
|
# define malloc_pageshift 12U
|
|
# define malloc_minsize 16U
|
|
# endif
|
|
# if defined(__alpha__)
|
|
# define malloc_pageshift 13U
|
|
# define malloc_minsize 16U
|
|
# endif
|
|
# if !defined(__NETBSD_SYSCALLS)
|
|
# define HAS_UTRACE
|
|
# endif
|
|
/*
|
|
* Make malloc/free/realloc thread-safe in libc for use with
|
|
* kernel threads.
|
|
*/
|
|
# include "libc_private.h"
|
|
# include "spinlock.h"
|
|
static spinlock_t thread_lock = _SPINLOCK_INITIALIZER;
|
|
# define THREAD_LOCK() if (__isthreaded) _SPINLOCK(&thread_lock);
|
|
# define THREAD_UNLOCK() if (__isthreaded) _SPINUNLOCK(&thread_lock);
|
|
#endif /* __FreeBSD__ */
|
|
|
|
#if defined(__sparc__) && defined(sun)
|
|
# define malloc_pageshift 12U
|
|
# define malloc_minsize 16U
|
|
# define MAP_ANON (0)
|
|
static int fdzero;
|
|
# define MMAP_FD fdzero
|
|
# define INIT_MMAP() \
|
|
{ if ((fdzero = _open(_PATH_DEVZERO, O_RDWR, 0000)) == -1) \
|
|
wrterror("open of /dev/zero"); }
|
|
# define MADV_FREE MADV_DONTNEED
|
|
#endif /* __sparc__ */
|
|
|
|
/* Insert your combination here... */
|
|
#if defined(__FOOCPU__) && defined(__BAROS__)
|
|
# define malloc_pageshift 12U
|
|
# define malloc_minsize 16U
|
|
#endif /* __FOOCPU__ && __BAROS__ */
|
|
|
|
|
|
/*
|
|
* No user serviceable parts behind this point.
|
|
*/
|
|
#include <sys/types.h>
|
|
#include <sys/mman.h>
|
|
#include <errno.h>
|
|
#include <fcntl.h>
|
|
#include <paths.h>
|
|
#include <stddef.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
#include "un-namespace.h"
|
|
|
|
/*
|
|
* This structure describes a page worth of chunks.
|
|
*/
|
|
|
|
struct pginfo {
|
|
struct pginfo *next; /* next on the free list */
|
|
void *page; /* Pointer to the page */
|
|
u_short size; /* size of this page's chunks */
|
|
u_short shift; /* How far to shift for this size chunks */
|
|
u_short free; /* How many free chunks */
|
|
u_short total; /* How many chunk */
|
|
u_int bits[1]; /* Which chunks are free */
|
|
};
|
|
|
|
/*
|
|
* This structure describes a number of free pages.
|
|
*/
|
|
|
|
struct pgfree {
|
|
struct pgfree *next; /* next run of free pages */
|
|
struct pgfree *prev; /* prev run of free pages */
|
|
void *page; /* pointer to free pages */
|
|
void *end; /* pointer to end of free pages */
|
|
size_t size; /* number of bytes free */
|
|
};
|
|
|
|
/*
|
|
* How many bits per u_int in the bitmap.
|
|
* Change only if not 8 bits/byte
|
|
*/
|
|
#define MALLOC_BITS (8*sizeof(u_int))
|
|
|
|
/*
|
|
* Magic values to put in the page_directory
|
|
*/
|
|
#define MALLOC_NOT_MINE ((struct pginfo*) 0)
|
|
#define MALLOC_FREE ((struct pginfo*) 1)
|
|
#define MALLOC_FIRST ((struct pginfo*) 2)
|
|
#define MALLOC_FOLLOW ((struct pginfo*) 3)
|
|
#define MALLOC_MAGIC ((struct pginfo*) 4)
|
|
|
|
#ifndef malloc_pageshift
|
|
#define malloc_pageshift 12U
|
|
#endif
|
|
|
|
#ifndef malloc_minsize
|
|
#define malloc_minsize 16U
|
|
#endif
|
|
|
|
#if !defined(malloc_pagesize)
|
|
#define malloc_pagesize (1UL<<malloc_pageshift)
|
|
#endif
|
|
|
|
#if ((1<<malloc_pageshift) != malloc_pagesize)
|
|
#error "(1<<malloc_pageshift) != malloc_pagesize"
|
|
#endif
|
|
|
|
#ifndef malloc_maxsize
|
|
#define malloc_maxsize ((malloc_pagesize)>>1)
|
|
#endif
|
|
|
|
/* A mask for the offset inside a page. */
|
|
#define malloc_pagemask ((malloc_pagesize)-1)
|
|
|
|
#define pageround(foo) (((foo) + (malloc_pagemask))&(~(malloc_pagemask)))
|
|
#define ptr2index(foo) (((u_long)(foo) >> malloc_pageshift)-malloc_origo)
|
|
|
|
#ifndef THREAD_LOCK
|
|
#define THREAD_LOCK()
|
|
#endif
|
|
|
|
#ifndef THREAD_UNLOCK
|
|
#define THREAD_UNLOCK()
|
|
#endif
|
|
|
|
#ifndef MMAP_FD
|
|
#define MMAP_FD (-1)
|
|
#endif
|
|
|
|
#ifndef INIT_MMAP
|
|
#define INIT_MMAP()
|
|
#endif
|
|
|
|
/* Set when initialization has been done */
|
|
static unsigned malloc_started;
|
|
|
|
/* Recusion flag for public interface. */
|
|
static int malloc_active;
|
|
|
|
/* Number of free pages we cache */
|
|
static unsigned malloc_cache = 16;
|
|
|
|
/* The offset from pagenumber to index into the page directory */
|
|
static u_long malloc_origo;
|
|
|
|
/* The last index in the page directory we care about */
|
|
static u_long last_index;
|
|
|
|
/* Pointer to page directory. Allocated "as if with" malloc */
|
|
static struct pginfo **page_dir;
|
|
|
|
/* How many slots in the page directory */
|
|
static unsigned malloc_ninfo;
|
|
|
|
/* Free pages line up here */
|
|
static struct pgfree free_list;
|
|
|
|
/* Abort(), user doesn't handle problems. */
|
|
static int malloc_abort = 1;
|
|
|
|
/* Are we trying to die ? */
|
|
static int suicide;
|
|
|
|
/* always realloc ? */
|
|
static int malloc_realloc;
|
|
|
|
/* pass the kernel a hint on free pages ? */
|
|
static int malloc_hint = 0;
|
|
|
|
/* xmalloc behaviour ? */
|
|
static int malloc_xmalloc;
|
|
|
|
/* sysv behaviour for malloc(0) ? */
|
|
static int malloc_sysv;
|
|
|
|
/* zero fill ? */
|
|
static int malloc_zero;
|
|
|
|
/* junk fill ? */
|
|
static int malloc_junk = 1;
|
|
|
|
#ifdef HAS_UTRACE
|
|
|
|
/* utrace ? */
|
|
static int malloc_utrace;
|
|
|
|
struct ut { void *p; size_t s; void *r; };
|
|
|
|
void utrace __P((struct ut *, int));
|
|
|
|
#define UTRACE(a, b, c) \
|
|
if (malloc_utrace) \
|
|
{struct ut u; u.p=a; u.s = b; u.r=c; utrace(&u, sizeof u);}
|
|
#else /* !HAS_UTRACE */
|
|
#define UTRACE(a,b,c)
|
|
#endif /* HAS_UTRACE */
|
|
|
|
/* my last break. */
|
|
static void *malloc_brk;
|
|
|
|
/* one location cache for free-list holders */
|
|
static struct pgfree *px;
|
|
|
|
/* compile-time options */
|
|
char *_malloc_options;
|
|
|
|
/* Name of the current public function */
|
|
static char *malloc_func;
|
|
|
|
/* Macro for mmap */
|
|
#define MMAP(size) \
|
|
mmap(0, (size), PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE, \
|
|
MMAP_FD, 0);
|
|
|
|
/*
|
|
* Necessary function declarations
|
|
*/
|
|
static int extend_pgdir(u_long index);
|
|
static void *imalloc(size_t size);
|
|
static void ifree(void *ptr);
|
|
static void *irealloc(void *ptr, size_t size);
|
|
|
|
static void
|
|
wrtmessage(char *p1, char *p2, char *p3, char *p4)
|
|
{
|
|
|
|
_write(STDERR_FILENO, p1, strlen(p1));
|
|
_write(STDERR_FILENO, p2, strlen(p2));
|
|
_write(STDERR_FILENO, p3, strlen(p3));
|
|
_write(STDERR_FILENO, p4, strlen(p4));
|
|
}
|
|
|
|
void (*_malloc_message)(char *p1, char *p2, char *p3, char *p4) = wrtmessage;
|
|
|
|
extern char *__progname;
|
|
|
|
static void
|
|
wrterror(char *p)
|
|
{
|
|
|
|
suicide = 1;
|
|
_malloc_message(__progname, malloc_func, " error: ", p);
|
|
abort();
|
|
}
|
|
|
|
static void
|
|
wrtwarning(char *p)
|
|
{
|
|
|
|
if (malloc_abort)
|
|
wrterror(p);
|
|
_malloc_message(__progname, malloc_func, " warning: ", p);
|
|
}
|
|
|
|
/*
|
|
* Allocate a number of pages from the OS
|
|
*/
|
|
static void *
|
|
map_pages(size_t pages)
|
|
{
|
|
caddr_t result, tail;
|
|
|
|
result = (caddr_t)pageround((u_long)sbrk(0));
|
|
tail = result + (pages << malloc_pageshift);
|
|
|
|
if (brk(tail)) {
|
|
#ifdef EXTRA_SANITY
|
|
wrterror("(ES): map_pages fails\n");
|
|
#endif /* EXTRA_SANITY */
|
|
return 0;
|
|
}
|
|
|
|
last_index = ptr2index(tail) - 1;
|
|
malloc_brk = tail;
|
|
|
|
if ((last_index+1) >= malloc_ninfo && !extend_pgdir(last_index))
|
|
return 0;;
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* Extend page directory
|
|
*/
|
|
static int
|
|
extend_pgdir(u_long index)
|
|
{
|
|
struct pginfo **new, **old;
|
|
u_long i, oldlen;
|
|
|
|
/* Make it this many pages */
|
|
i = index * sizeof *page_dir;
|
|
i /= malloc_pagesize;
|
|
i += 2;
|
|
|
|
/* remember the old mapping size */
|
|
oldlen = malloc_ninfo * sizeof *page_dir;
|
|
|
|
/*
|
|
* NOTE: we allocate new pages and copy the directory rather than tempt
|
|
* fate by trying to "grow" the region.. There is nothing to prevent
|
|
* us from accidently re-mapping space that's been allocated by our caller
|
|
* via dlopen() or other mmap().
|
|
*
|
|
* The copy problem is not too bad, as there is 4K of page index per
|
|
* 4MB of malloc arena.
|
|
*
|
|
* We can totally avoid the copy if we open a file descriptor to associate
|
|
* the anon mappings with. Then, when we remap the pages at the new
|
|
* address, the old pages will be "magically" remapped.. But this means
|
|
* keeping open a "secret" file descriptor.....
|
|
*/
|
|
|
|
/* Get new pages */
|
|
new = (struct pginfo**) MMAP(i * malloc_pagesize);
|
|
if (new == (struct pginfo **)-1)
|
|
return 0;
|
|
|
|
/* Copy the old stuff */
|
|
memcpy(new, page_dir,
|
|
malloc_ninfo * sizeof *page_dir);
|
|
|
|
/* register the new size */
|
|
malloc_ninfo = i * malloc_pagesize / sizeof *page_dir;
|
|
|
|
/* swap the pointers */
|
|
old = page_dir;
|
|
page_dir = new;
|
|
|
|
/* Now free the old stuff */
|
|
munmap(old, oldlen);
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* Initialize the world
|
|
*/
|
|
static void
|
|
malloc_init ()
|
|
{
|
|
char *p, b[64];
|
|
int i, j;
|
|
int errnosave;
|
|
|
|
INIT_MMAP();
|
|
|
|
#ifdef EXTRA_SANITY
|
|
malloc_junk = 1;
|
|
#endif /* EXTRA_SANITY */
|
|
|
|
for (i = 0; i < 3; i++) {
|
|
if (i == 0) {
|
|
errnosave = errno;
|
|
j = readlink("/etc/malloc.conf", b, sizeof b - 1);
|
|
errno = errnosave;
|
|
if (j <= 0)
|
|
continue;
|
|
b[j] = '\0';
|
|
p = b;
|
|
} else if (i == 1) {
|
|
p = getenv("MALLOC_OPTIONS");
|
|
} else {
|
|
p = _malloc_options;
|
|
}
|
|
for (; p && *p; p++) {
|
|
switch (*p) {
|
|
case '>': malloc_cache <<= 1; break;
|
|
case '<': malloc_cache >>= 1; break;
|
|
case 'a': malloc_abort = 0; break;
|
|
case 'A': malloc_abort = 1; break;
|
|
case 'h': malloc_hint = 0; break;
|
|
case 'H': malloc_hint = 1; break;
|
|
case 'r': malloc_realloc = 0; break;
|
|
case 'R': malloc_realloc = 1; break;
|
|
case 'j': malloc_junk = 0; break;
|
|
case 'J': malloc_junk = 1; break;
|
|
#ifdef HAS_UTRACE
|
|
case 'u': malloc_utrace = 0; break;
|
|
case 'U': malloc_utrace = 1; break;
|
|
#endif
|
|
case 'v': malloc_sysv = 0; break;
|
|
case 'V': malloc_sysv = 1; break;
|
|
case 'x': malloc_xmalloc = 0; break;
|
|
case 'X': malloc_xmalloc = 1; break;
|
|
case 'z': malloc_zero = 0; break;
|
|
case 'Z': malloc_zero = 1; break;
|
|
default:
|
|
j = malloc_abort;
|
|
malloc_abort = 0;
|
|
wrtwarning("unknown char in MALLOC_OPTIONS\n");
|
|
malloc_abort = j;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
UTRACE(0, 0, 0);
|
|
|
|
/*
|
|
* We want junk in the entire allocation, and zero only in the part
|
|
* the user asked for.
|
|
*/
|
|
if (malloc_zero)
|
|
malloc_junk=1;
|
|
|
|
/*
|
|
* If we run with junk (or implicitly from above: zero), we want to
|
|
* force realloc() to get new storage, so we can DTRT with it.
|
|
*/
|
|
if (malloc_junk)
|
|
malloc_realloc=1;
|
|
|
|
/* Allocate one page for the page directory */
|
|
page_dir = (struct pginfo **) MMAP(malloc_pagesize);
|
|
|
|
if (page_dir == (struct pginfo **) -1)
|
|
wrterror("mmap(2) failed, check limits.\n");
|
|
|
|
/*
|
|
* We need a maximum of malloc_pageshift buckets, steal these from the
|
|
* front of the page_directory;
|
|
*/
|
|
malloc_origo = ((u_long)pageround((u_long)sbrk(0))) >> malloc_pageshift;
|
|
malloc_origo -= malloc_pageshift;
|
|
|
|
malloc_ninfo = malloc_pagesize / sizeof *page_dir;
|
|
|
|
/* Recalculate the cache size in bytes, and make sure it's nonzero */
|
|
|
|
if (!malloc_cache)
|
|
malloc_cache++;
|
|
|
|
malloc_cache <<= malloc_pageshift;
|
|
|
|
/*
|
|
* This is a nice hack from Kaleb Keithly (kaleb@x.org).
|
|
* We can sbrk(2) further back when we keep this on a low address.
|
|
*/
|
|
px = (struct pgfree *) imalloc (sizeof *px);
|
|
|
|
/* Been here, done that */
|
|
malloc_started++;
|
|
}
|
|
|
|
/*
|
|
* Allocate a number of complete pages
|
|
*/
|
|
static void *
|
|
malloc_pages(size_t size)
|
|
{
|
|
void *p, *delay_free = 0;
|
|
size_t i;
|
|
struct pgfree *pf;
|
|
u_long index;
|
|
|
|
size = pageround(size);
|
|
|
|
p = 0;
|
|
|
|
/* Look for free pages before asking for more */
|
|
for(pf = free_list.next; pf; pf = pf->next) {
|
|
|
|
#ifdef EXTRA_SANITY
|
|
if (pf->size & malloc_pagemask)
|
|
wrterror("(ES): junk length entry on free_list\n");
|
|
if (!pf->size)
|
|
wrterror("(ES): zero length entry on free_list\n");
|
|
if (pf->page == pf->end)
|
|
wrterror("(ES): zero entry on free_list\n");
|
|
if (pf->page > pf->end)
|
|
wrterror("(ES): sick entry on free_list\n");
|
|
if ((void*)pf->page >= (void*)sbrk(0))
|
|
wrterror("(ES): entry on free_list past brk\n");
|
|
if (page_dir[ptr2index(pf->page)] != MALLOC_FREE)
|
|
wrterror("(ES): non-free first page on free-list\n");
|
|
if (page_dir[ptr2index(pf->end)-1] != MALLOC_FREE)
|
|
wrterror("(ES): non-free last page on free-list\n");
|
|
#endif /* EXTRA_SANITY */
|
|
|
|
if (pf->size < size)
|
|
continue;
|
|
|
|
if (pf->size == size) {
|
|
p = pf->page;
|
|
if (pf->next)
|
|
pf->next->prev = pf->prev;
|
|
pf->prev->next = pf->next;
|
|
delay_free = pf;
|
|
break;
|
|
}
|
|
|
|
p = pf->page;
|
|
pf->page = (char *)pf->page + size;
|
|
pf->size -= size;
|
|
break;
|
|
}
|
|
|
|
#ifdef EXTRA_SANITY
|
|
if (p && page_dir[ptr2index(p)] != MALLOC_FREE)
|
|
wrterror("(ES): allocated non-free page on free-list\n");
|
|
#endif /* EXTRA_SANITY */
|
|
|
|
size >>= malloc_pageshift;
|
|
|
|
/* Map new pages */
|
|
if (!p)
|
|
p = map_pages(size);
|
|
|
|
if (p) {
|
|
|
|
index = ptr2index(p);
|
|
page_dir[index] = MALLOC_FIRST;
|
|
for (i=1;i<size;i++)
|
|
page_dir[index+i] = MALLOC_FOLLOW;
|
|
|
|
if (malloc_junk)
|
|
memset(p, SOME_JUNK, size << malloc_pageshift);
|
|
}
|
|
|
|
if (delay_free) {
|
|
if (!px)
|
|
px = delay_free;
|
|
else
|
|
ifree(delay_free);
|
|
}
|
|
|
|
return p;
|
|
}
|
|
|
|
/*
|
|
* Allocate a page of fragments
|
|
*/
|
|
|
|
static __inline__ int
|
|
malloc_make_chunks(int bits)
|
|
{
|
|
struct pginfo *bp;
|
|
void *pp;
|
|
int i, k, l;
|
|
|
|
/* Allocate a new bucket */
|
|
pp = malloc_pages(malloc_pagesize);
|
|
if (!pp)
|
|
return 0;
|
|
|
|
/* Find length of admin structure */
|
|
l = offsetof(struct pginfo, bits[0]);
|
|
l += sizeof bp->bits[0] *
|
|
(((malloc_pagesize >> bits)+MALLOC_BITS-1) / MALLOC_BITS);
|
|
|
|
/* Don't waste more than two chunks on this */
|
|
if ((1<<(bits)) <= l+l) {
|
|
bp = (struct pginfo *)pp;
|
|
} else {
|
|
bp = (struct pginfo *)imalloc(l);
|
|
if (!bp) {
|
|
ifree(pp);
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
bp->size = (1<<bits);
|
|
bp->shift = bits;
|
|
bp->total = bp->free = malloc_pagesize >> bits;
|
|
bp->page = pp;
|
|
|
|
/* set all valid bits in the bitmap */
|
|
k = bp->total;
|
|
i = 0;
|
|
|
|
/* Do a bunch at a time */
|
|
for(;k-i >= MALLOC_BITS; i += MALLOC_BITS)
|
|
bp->bits[i / MALLOC_BITS] = ~0;
|
|
|
|
for(; i < k; i++)
|
|
bp->bits[i/MALLOC_BITS] |= 1<<(i%MALLOC_BITS);
|
|
|
|
if (bp == bp->page) {
|
|
/* Mark the ones we stole for ourselves */
|
|
for(i=0;l > 0;i++) {
|
|
bp->bits[i/MALLOC_BITS] &= ~(1<<(i%MALLOC_BITS));
|
|
bp->free--;
|
|
bp->total--;
|
|
l -= (1 << bits);
|
|
}
|
|
}
|
|
|
|
/* MALLOC_LOCK */
|
|
|
|
page_dir[ptr2index(pp)] = bp;
|
|
|
|
bp->next = page_dir[bits];
|
|
page_dir[bits] = bp;
|
|
|
|
/* MALLOC_UNLOCK */
|
|
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* Allocate a fragment
|
|
*/
|
|
static void *
|
|
malloc_bytes(size_t size)
|
|
{
|
|
int i,j;
|
|
u_int u;
|
|
struct pginfo *bp;
|
|
int k;
|
|
u_int *lp;
|
|
|
|
/* Don't bother with anything less than this */
|
|
if (size < malloc_minsize)
|
|
size = malloc_minsize;
|
|
|
|
/* Find the right bucket */
|
|
j = 1;
|
|
i = size-1;
|
|
while (i >>= 1)
|
|
j++;
|
|
|
|
/* If it's empty, make a page more of that size chunks */
|
|
if (!page_dir[j] && !malloc_make_chunks(j))
|
|
return 0;
|
|
|
|
bp = page_dir[j];
|
|
|
|
/* Find first word of bitmap which isn't empty */
|
|
for (lp = bp->bits; !*lp; lp++)
|
|
;
|
|
|
|
/* Find that bit, and tweak it */
|
|
u = 1;
|
|
k = 0;
|
|
while (!(*lp & u)) {
|
|
u += u;
|
|
k++;
|
|
}
|
|
*lp ^= u;
|
|
|
|
/* If there are no more free, remove from free-list */
|
|
if (!--bp->free) {
|
|
page_dir[j] = bp->next;
|
|
bp->next = 0;
|
|
}
|
|
|
|
/* Adjust to the real offset of that chunk */
|
|
k += (lp-bp->bits)*MALLOC_BITS;
|
|
k <<= bp->shift;
|
|
|
|
if (malloc_junk)
|
|
memset((u_char*)bp->page + k, SOME_JUNK, bp->size);
|
|
|
|
return (u_char *)bp->page + k;
|
|
}
|
|
|
|
/*
|
|
* Allocate a piece of memory
|
|
*/
|
|
static void *
|
|
imalloc(size_t size)
|
|
{
|
|
void *result;
|
|
|
|
if (suicide)
|
|
abort();
|
|
|
|
if ((size + malloc_pagesize) < size) /* Check for overflow */
|
|
result = 0;
|
|
else if (size <= malloc_maxsize)
|
|
result = malloc_bytes(size);
|
|
else
|
|
result = malloc_pages(size);
|
|
|
|
if (malloc_zero && result)
|
|
memset(result, 0, size);
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* Change the size of an allocation.
|
|
*/
|
|
static void *
|
|
irealloc(void *ptr, size_t size)
|
|
{
|
|
void *p;
|
|
u_long osize, index;
|
|
struct pginfo **mp;
|
|
int i;
|
|
|
|
if (suicide)
|
|
abort();
|
|
|
|
index = ptr2index(ptr);
|
|
|
|
if (index < malloc_pageshift) {
|
|
wrtwarning("junk pointer, too low to make sense.\n");
|
|
return 0;
|
|
}
|
|
|
|
if (index > last_index) {
|
|
wrtwarning("junk pointer, too high to make sense.\n");
|
|
return 0;
|
|
}
|
|
|
|
mp = &page_dir[index];
|
|
|
|
if (*mp == MALLOC_FIRST) { /* Page allocation */
|
|
|
|
/* Check the pointer */
|
|
if ((u_long)ptr & malloc_pagemask) {
|
|
wrtwarning("modified (page-) pointer.\n");
|
|
return 0;
|
|
}
|
|
|
|
/* Find the size in bytes */
|
|
for (osize = malloc_pagesize; *++mp == MALLOC_FOLLOW;)
|
|
osize += malloc_pagesize;
|
|
|
|
if (!malloc_realloc && /* unless we have to, */
|
|
size <= osize && /* .. or are too small, */
|
|
size > (osize - malloc_pagesize)) { /* .. or can free a page, */
|
|
return ptr; /* don't do anything. */
|
|
}
|
|
|
|
} else if (*mp >= MALLOC_MAGIC) { /* Chunk allocation */
|
|
|
|
/* Check the pointer for sane values */
|
|
if (((u_long)ptr & ((*mp)->size-1))) {
|
|
wrtwarning("modified (chunk-) pointer.\n");
|
|
return 0;
|
|
}
|
|
|
|
/* Find the chunk index in the page */
|
|
i = ((u_long)ptr & malloc_pagemask) >> (*mp)->shift;
|
|
|
|
/* Verify that it isn't a free chunk already */
|
|
if ((*mp)->bits[i/MALLOC_BITS] & (1<<(i%MALLOC_BITS))) {
|
|
wrtwarning("chunk is already free.\n");
|
|
return 0;
|
|
}
|
|
|
|
osize = (*mp)->size;
|
|
|
|
if (!malloc_realloc && /* Unless we have to, */
|
|
size < osize && /* ..or are too small, */
|
|
(size > osize/2 || /* ..or could use a smaller size, */
|
|
osize == malloc_minsize)) { /* ..(if there is one) */
|
|
return ptr; /* ..Don't do anything */
|
|
}
|
|
|
|
} else {
|
|
wrtwarning("pointer to wrong page.\n");
|
|
return 0;
|
|
}
|
|
|
|
p = imalloc(size);
|
|
|
|
if (p) {
|
|
/* copy the lesser of the two sizes, and free the old one */
|
|
if (!size || !osize)
|
|
;
|
|
else if (osize < size)
|
|
memcpy(p, ptr, osize);
|
|
else
|
|
memcpy(p, ptr, size);
|
|
ifree(ptr);
|
|
}
|
|
return p;
|
|
}
|
|
|
|
/*
|
|
* Free a sequence of pages
|
|
*/
|
|
|
|
static __inline__ void
|
|
free_pages(void *ptr, u_long index, struct pginfo *info)
|
|
{
|
|
u_long i;
|
|
struct pgfree *pf, *pt=0;
|
|
u_long l;
|
|
void *tail;
|
|
|
|
if (info == MALLOC_FREE) {
|
|
wrtwarning("page is already free.\n");
|
|
return;
|
|
}
|
|
|
|
if (info != MALLOC_FIRST) {
|
|
wrtwarning("pointer to wrong page.\n");
|
|
return;
|
|
}
|
|
|
|
if ((u_long)ptr & malloc_pagemask) {
|
|
wrtwarning("modified (page-) pointer.\n");
|
|
return;
|
|
}
|
|
|
|
/* Count how many pages and mark them free at the same time */
|
|
page_dir[index] = MALLOC_FREE;
|
|
for (i = 1; page_dir[index+i] == MALLOC_FOLLOW; i++)
|
|
page_dir[index + i] = MALLOC_FREE;
|
|
|
|
l = i << malloc_pageshift;
|
|
|
|
if (malloc_junk)
|
|
memset(ptr, SOME_JUNK, l);
|
|
|
|
if (malloc_hint)
|
|
madvise(ptr, l, MADV_FREE);
|
|
|
|
tail = (char *)ptr+l;
|
|
|
|
/* add to free-list */
|
|
if (!px)
|
|
px = imalloc(sizeof *pt); /* This cannot fail... */
|
|
px->page = ptr;
|
|
px->end = tail;
|
|
px->size = l;
|
|
if (!free_list.next) {
|
|
|
|
/* Nothing on free list, put this at head */
|
|
px->next = free_list.next;
|
|
px->prev = &free_list;
|
|
free_list.next = px;
|
|
pf = px;
|
|
px = 0;
|
|
|
|
} else {
|
|
|
|
/* Find the right spot, leave pf pointing to the modified entry. */
|
|
tail = (char *)ptr+l;
|
|
|
|
for(pf = free_list.next; pf->end < ptr && pf->next; pf = pf->next)
|
|
; /* Race ahead here */
|
|
|
|
if (pf->page > tail) {
|
|
/* Insert before entry */
|
|
px->next = pf;
|
|
px->prev = pf->prev;
|
|
pf->prev = px;
|
|
px->prev->next = px;
|
|
pf = px;
|
|
px = 0;
|
|
} else if (pf->end == ptr ) {
|
|
/* Append to the previous entry */
|
|
pf->end = (char *)pf->end + l;
|
|
pf->size += l;
|
|
if (pf->next && pf->end == pf->next->page ) {
|
|
/* And collapse the next too. */
|
|
pt = pf->next;
|
|
pf->end = pt->end;
|
|
pf->size += pt->size;
|
|
pf->next = pt->next;
|
|
if (pf->next)
|
|
pf->next->prev = pf;
|
|
}
|
|
} else if (pf->page == tail) {
|
|
/* Prepend to entry */
|
|
pf->size += l;
|
|
pf->page = ptr;
|
|
} else if (!pf->next) {
|
|
/* Append at tail of chain */
|
|
px->next = 0;
|
|
px->prev = pf;
|
|
pf->next = px;
|
|
pf = px;
|
|
px = 0;
|
|
} else {
|
|
wrterror("freelist is destroyed.\n");
|
|
}
|
|
}
|
|
|
|
/* Return something to OS ? */
|
|
if (!pf->next && /* If we're the last one, */
|
|
pf->size > malloc_cache && /* ..and the cache is full, */
|
|
pf->end == malloc_brk && /* ..and none behind us, */
|
|
malloc_brk == sbrk(0)) { /* ..and it's OK to do... */
|
|
|
|
/*
|
|
* Keep the cache intact. Notice that the '>' above guarantees that
|
|
* the pf will always have at least one page afterwards.
|
|
*/
|
|
pf->end = (char *)pf->page + malloc_cache;
|
|
pf->size = malloc_cache;
|
|
|
|
brk(pf->end);
|
|
malloc_brk = pf->end;
|
|
|
|
index = ptr2index(pf->end);
|
|
last_index = index - 1;
|
|
|
|
for(i=index;i <= last_index;)
|
|
page_dir[i++] = MALLOC_NOT_MINE;
|
|
|
|
/* XXX: We could realloc/shrink the pagedir here I guess. */
|
|
}
|
|
if (pt)
|
|
ifree(pt);
|
|
}
|
|
|
|
/*
|
|
* Free a chunk, and possibly the page it's on, if the page becomes empty.
|
|
*/
|
|
|
|
static __inline__ void
|
|
free_bytes(void *ptr, u_long index, struct pginfo *info)
|
|
{
|
|
int i;
|
|
struct pginfo **mp;
|
|
void *vp;
|
|
|
|
/* Find the chunk number on the page */
|
|
i = ((u_long)ptr & malloc_pagemask) >> info->shift;
|
|
|
|
if (((u_long)ptr & (info->size-1))) {
|
|
wrtwarning("modified (chunk-) pointer.\n");
|
|
return;
|
|
}
|
|
|
|
if (info->bits[i/MALLOC_BITS] & (1<<(i%MALLOC_BITS))) {
|
|
wrtwarning("chunk is already free.\n");
|
|
return;
|
|
}
|
|
|
|
if (malloc_junk)
|
|
memset(ptr, SOME_JUNK, info->size);
|
|
|
|
info->bits[i/MALLOC_BITS] |= 1<<(i%MALLOC_BITS);
|
|
info->free++;
|
|
|
|
mp = page_dir + info->shift;
|
|
|
|
if (info->free == 1) {
|
|
|
|
/* Page became non-full */
|
|
|
|
mp = page_dir + info->shift;
|
|
/* Insert in address order */
|
|
while (*mp && (*mp)->next && (*mp)->next->page < info->page)
|
|
mp = &(*mp)->next;
|
|
info->next = *mp;
|
|
*mp = info;
|
|
return;
|
|
}
|
|
|
|
if (info->free != info->total)
|
|
return;
|
|
|
|
/* Find & remove this page in the queue */
|
|
while (*mp != info) {
|
|
mp = &((*mp)->next);
|
|
#ifdef EXTRA_SANITY
|
|
if (!*mp)
|
|
wrterror("(ES): Not on queue\n");
|
|
#endif /* EXTRA_SANITY */
|
|
}
|
|
*mp = info->next;
|
|
|
|
/* Free the page & the info structure if need be */
|
|
page_dir[ptr2index(info->page)] = MALLOC_FIRST;
|
|
vp = info->page; /* Order is important ! */
|
|
if(vp != (void*)info)
|
|
ifree(info);
|
|
ifree(vp);
|
|
}
|
|
|
|
static void
|
|
ifree(void *ptr)
|
|
{
|
|
struct pginfo *info;
|
|
u_long index;
|
|
|
|
/* This is legal */
|
|
if (!ptr)
|
|
return;
|
|
|
|
if (!malloc_started) {
|
|
wrtwarning("malloc() has never been called.\n");
|
|
return;
|
|
}
|
|
|
|
/* If we're already sinking, don't make matters any worse. */
|
|
if (suicide)
|
|
return;
|
|
|
|
index = ptr2index(ptr);
|
|
|
|
if (index < malloc_pageshift) {
|
|
wrtwarning("junk pointer, too low to make sense.\n");
|
|
return;
|
|
}
|
|
|
|
if (index > last_index) {
|
|
wrtwarning("junk pointer, too high to make sense.\n");
|
|
return;
|
|
}
|
|
|
|
info = page_dir[index];
|
|
|
|
if (info < MALLOC_MAGIC)
|
|
free_pages(ptr, index, info);
|
|
else
|
|
free_bytes(ptr, index, info);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* These are the public exported interface routines.
|
|
*/
|
|
|
|
|
|
void *
|
|
malloc(size_t size)
|
|
{
|
|
register void *r;
|
|
|
|
THREAD_LOCK();
|
|
malloc_func = " in malloc():";
|
|
if (malloc_active++) {
|
|
wrtwarning("recursive call.\n");
|
|
malloc_active--;
|
|
THREAD_UNLOCK();
|
|
return (0);
|
|
}
|
|
if (!malloc_started)
|
|
malloc_init();
|
|
if (malloc_sysv && !size)
|
|
r = 0;
|
|
else
|
|
r = imalloc(size);
|
|
UTRACE(0, size, r);
|
|
malloc_active--;
|
|
THREAD_UNLOCK();
|
|
if (malloc_xmalloc && !r)
|
|
wrterror("out of memory.\n");
|
|
return (r);
|
|
}
|
|
|
|
void
|
|
free(void *ptr)
|
|
{
|
|
THREAD_LOCK();
|
|
malloc_func = " in free():";
|
|
if (malloc_active++) {
|
|
wrtwarning("recursive call.\n");
|
|
malloc_active--;
|
|
return;
|
|
} else {
|
|
ifree(ptr);
|
|
UTRACE(ptr, 0, 0);
|
|
}
|
|
malloc_active--;
|
|
THREAD_UNLOCK();
|
|
return;
|
|
}
|
|
|
|
void *
|
|
realloc(void *ptr, size_t size)
|
|
{
|
|
register void *r;
|
|
|
|
THREAD_LOCK();
|
|
malloc_func = " in realloc():";
|
|
if (malloc_active++) {
|
|
wrtwarning("recursive call.\n");
|
|
malloc_active--;
|
|
return (0);
|
|
}
|
|
if (ptr && !malloc_started) {
|
|
wrtwarning("malloc() has never been called.\n");
|
|
ptr = 0;
|
|
}
|
|
if (!malloc_started)
|
|
malloc_init();
|
|
if (malloc_sysv && !size) {
|
|
ifree(ptr);
|
|
r = 0;
|
|
} else if (!ptr) {
|
|
r = imalloc(size);
|
|
} else {
|
|
r = irealloc(ptr, size);
|
|
}
|
|
UTRACE(ptr, size, r);
|
|
malloc_active--;
|
|
THREAD_UNLOCK();
|
|
if (malloc_xmalloc && !r)
|
|
wrterror("out of memory.\n");
|
|
return (r);
|
|
}
|
|
|