freebsd-nq/lib/libstand/zalloc.c
Doug Rabson f069bf5a2c * Enable old UFS compatibility code for booting from Digital Unix formatted
disks.
* Fix a whole raft of warnings, printf and otherwise.
* Make zalloc work for alpha (just a case of using the right typedef).
* Add some (disabled) malloc debug printing to stand.h.
1998-09-26 10:48:50 +00:00

593 lines
15 KiB
C

/*
* This module derived from code donated to the FreeBSD Project by
* Matthew Dillon <dillon@backplane.com>
*
* Copyright (c) 1998 The FreeBSD Project
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*
* $Id: zalloc.c,v 1.2 1998/09/26 03:24:14 dillon Exp $
*/
/*
* LIB/MEMORY/ZALLOC.C - self contained low-overhead memory pool/allocation
* subsystem
*
* This subsystem implements memory pools and memory allocation
* routines.
*
* Pools are managed via a linked list of 'free' areas. Allocating
* memory creates holes in the freelist, freeing memory fills them.
* Since the freelist consists only of free memory areas, it is possible
* to allocate the entire pool without incuring any structural overhead.
*
* The system works best when allocating similarly-sized chunks of
* memory. Care must be taken to avoid fragmentation when
* allocating/deallocating dissimilar chunks.
*
* When a memory pool is first allocated, the entire pool is marked as
* allocated. This is done mainly because we do not want to modify any
* portion of a pool's data area until we are given permission. The
* caller must explicitly deallocate portions of the pool to make them
* available.
*
* z[n]xalloc() works like z[n]alloc() but the allocation is made from
* within the specified address range. If the segment could not be
* allocated, NULL is returned. WARNING! The address range will be
* aligned to an 8 or 16 byte boundry depending on the cpu so if you
* give an unaligned address range, unexpected results may occur.
*
* If a standard allocation fails, the reclaim function will be called
* to recover some space. This usually causes other portions of the
* same pool to be released. Memory allocations at this low level
* should not block but you can do that too in your reclaim function
* if you want. Reclaim does not function when z[n]xalloc() is used,
* only for z[n]alloc().
*
* Allocation and frees of 0 bytes are valid operations.
*/
#include "zalloc_defs.h"
Prototype struct MemPool *DummyStructMemPool;
Library void *znalloc(struct MemPool *mpool, iaddr_t bytes);
Library void *zalloc(struct MemPool *mpool, iaddr_t bytes);
Library void *zallocAlign(struct MemPool *mpool, iaddr_t bytes, iaddr_t align);
Library void *zxalloc(struct MemPool *mp, void *addr1, void *addr2, iaddr_t bytes);
Library void *znxalloc(struct MemPool *mp, void *addr1, void *addr2, iaddr_t bytes);
Library char *zallocStr(struct MemPool *mpool, const char *s, int slen);
Library void zfree(struct MemPool *mpool, void *ptr, iaddr_t bytes);
Library void zfreeStr(struct MemPool *mpool, char *s);
Library void zinitPool(struct MemPool *mp, const char *id, void (*fpanic)(const char *ctl, ...), int (*freclaim)(struct MemPool *memPool, iaddr_t bytes), void *pBase, iaddr_t pSize);
Library void zclearPool(struct MemPool *mp);
Library void znop(const char *ctl, ...);
Library int znot(struct MemPool *memPool, iaddr_t bytes);
Library void zallocstats(struct MemPool *mp);
/*
* znop() - panic function if none supplied.
*/
void
znop(const char *ctl, ...)
{
}
/*
* znot() - reclaim function if none supplied
*/
int
znot(struct MemPool *memPool, iaddr_t bytes)
{
return(-1);
}
#ifndef MALLOCLIB
/*
* zalloc() - allocate and zero memory from pool. Call reclaim
* and retry if appropriate, return NULL if unable to allocate
* memory.
*/
void *
zalloc(MemPool *mp, iaddr_t bytes)
{
void *ptr;
if ((ptr = znalloc(mp, bytes)) != NULL)
bzero(ptr, bytes);
return(ptr);
}
/*
* zallocAlign() - allocate and zero memory from pool, enforce specified
* alignment (must be power of 2) on allocated memory.
*/
void *
zallocAlign(struct MemPool *mp, iaddr_t bytes, iaddr_t align)
{
void *ptr;
--align;
bytes = (bytes + align) & ~align;
if ((ptr = znalloc(mp, bytes)) != NULL) {
bzero(ptr, bytes);
}
return(ptr);
}
#endif
/*
* znalloc() - allocate memory (without zeroing) from pool. Call reclaim
* and retry if appropriate, return NULL if unable to allocate
* memory.
*/
void *
znalloc(MemPool *mp, iaddr_t bytes)
{
/*
* align according to pool object size (can be 0). This is
* inclusive of the MEMNODE_SIZE_MASK minimum alignment.
*
*/
bytes = (bytes + MEMNODE_SIZE_MASK) & ~MEMNODE_SIZE_MASK;
if (bytes == 0)
return((void *)-1);
do {
/*
* locate freelist entry big enough to hold the object. If all objects
* are the same size, this is a constant-time function.
*/
if (bytes <= mp->mp_Size - mp->mp_Used) {
MemNode **pmn;
MemNode *mn;
for (pmn = &mp->mp_First; (mn=*pmn) != NULL; pmn = &mn->mr_Next) {
if (bytes > mn->mr_Bytes)
continue;
/*
* Cut a chunk of memory out of the beginning of this
* block and fixup the link appropriately.
*/
{
char *ptr = (char *)mn;
if (mn->mr_Bytes == bytes) {
*pmn = mn->mr_Next;
} else {
mn = (MemNode *)((char *)mn + bytes);
mn->mr_Next = ((MemNode *)ptr)->mr_Next;
mn->mr_Bytes = ((MemNode *)ptr)->mr_Bytes - bytes;
*pmn = mn;
}
mp->mp_Used += bytes;
return(ptr);
}
}
}
} while (mp->mp_Reclaim(mp, bytes) == 0);
/*
* Memory pool is full, return NULL.
*/
return(NULL);
}
#ifndef MALLOCLIB
/*
* z[n]xalloc() - allocate memory from within a specific address region.
* If allocating AT a specific address, then addr2 must be
* set to addr1 + bytes (and this only works if addr1 is
* already aligned). addr1 and addr2 are aligned by
* MEMNODE_SIZE_MASK + 1 (i.e. they wlill be 8 or 16 byte
* aligned depending on the machine core).
*/
void *
zxalloc(MemPool *mp, void *addr1, void *addr2, iaddr_t bytes)
{
void *ptr;
if ((ptr = znxalloc(mp, addr1, addr2, bytes)) != NULL)
bzero(ptr, bytes);
return(ptr);
}
void *
znxalloc(MemPool *mp, void *addr1, void *addr2, iaddr_t bytes)
{
/*
* align according to pool object size (can be 0). This is
* inclusive of the MEMNODE_SIZE_MASK minimum alignment.
*/
bytes = (bytes + MEMNODE_SIZE_MASK) & ~MEMNODE_SIZE_MASK;
addr1= (void *)(((iaddr_t)addr1 + MEMNODE_SIZE_MASK) & ~MEMNODE_SIZE_MASK);
addr2= (void *)(((iaddr_t)addr2 + MEMNODE_SIZE_MASK) & ~MEMNODE_SIZE_MASK);
if (bytes == 0)
return((void *)addr1);
/*
* Locate freelist entry big enough to hold the object that is within
* the allowed address range.
*/
if (bytes <= mp->mp_Size - mp->mp_Used) {
MemNode **pmn;
MemNode *mn;
for (pmn = &mp->mp_First; (mn = *pmn) != NULL; pmn = &mn->mr_Next) {
int mrbytes = mn->mr_Bytes;
int offset = 0;
/*
* offset from base of mn to satisfy addr1. 0 or positive
*/
if ((char *)mn < (char *)addr1)
offset = (char *)addr1 - (char *)mn;
/*
* truncate mrbytes to satisfy addr2. mrbytes may go negative
* if the mn is beyond the last acceptable address.
*/
if ((char *)mn + mrbytes > (char *)addr2)
mrbytes = (saddr_t)((iaddr_t)addr2 - (iaddr_t)mn); /* signed */
/*
* beyond last acceptable address.
*
* before first acceptable address (if offset > mrbytes, the
* second conditional will always succeed).
*
* area overlapping acceptable address range is not big enough.
*/
if (mrbytes < 0)
break;
if (mrbytes - offset < bytes)
continue;
/*
* Cut a chunk of memory out of the block and fixup the link
* appropriately.
*
* If offset != 0, we have to cut a chunk out from the middle of
* the block.
*/
if (offset) {
MemNode *mnew = (MemNode *)((char *)mn + offset);
mnew->mr_Bytes = mn->mr_Bytes - offset;
mnew->mr_Next = mn->mr_Next;
mn->mr_Bytes = offset;
mn->mr_Next = mnew;
pmn = &mn->mr_Next;
mn = mnew;
}
{
char *ptr = (char *)mn;
if (mn->mr_Bytes == bytes) {
*pmn = mn->mr_Next;
} else {
mn = (MemNode *)((char *)mn + bytes);
mn->mr_Next = ((MemNode *)ptr)->mr_Next;
mn->mr_Bytes = ((MemNode *)ptr)->mr_Bytes - bytes;
*pmn = mn;
}
mp->mp_Used += bytes;
return(ptr);
}
}
}
return(NULL);
}
#endif
/*
* zfree() - free previously allocated memory
*/
void
zfree(MemPool *mp, void *ptr, iaddr_t bytes)
{
/*
* align according to pool object size (can be 0). This is
* inclusive of the MEMNODE_SIZE_MASK minimum alignment.
*/
bytes = (bytes + MEMNODE_SIZE_MASK) & ~MEMNODE_SIZE_MASK;
if (bytes == 0)
return;
/*
* panic if illegal pointer
*/
if ((char *)ptr < (char *)mp->mp_Base ||
(char *)ptr + bytes > (char *)mp->mp_End ||
((iaddr_t)ptr & MEMNODE_SIZE_MASK) != 0
) {
mp->mp_Panic(
"zfree(%s,0x%08lx,%d): wild pointer",
mp->mp_Ident,
(long)ptr,
bytes
);
}
/*
* free the segment
*/
{
MemNode **pmn;
MemNode *mn;
mp->mp_Used -= bytes;
for (pmn = &mp->mp_First; (mn = *pmn) != NULL; pmn = &mn->mr_Next) {
/*
* If area between last node and current node
* - check range
* - check merge with next area
* - check merge with previous area
*/
if ((char *)ptr <= (char *)mn) {
/*
* range check
*/
if ((char *)ptr + bytes > (char *)mn) {
mp->mp_Panic("zfree(%s,0x%08lx,%d): corrupt memlist1",
mp->mp_Ident,
(long)ptr,
bytes
);
}
/*
* merge against next area or create independant area
*/
if ((char *)ptr + bytes == (char *)mn) {
((MemNode *)ptr)->mr_Next = mn->mr_Next;
((MemNode *)ptr)->mr_Bytes= bytes + mn->mr_Bytes;
} else {
((MemNode *)ptr)->mr_Next = mn;
((MemNode *)ptr)->mr_Bytes= bytes;
}
*pmn = mn = (MemNode *)ptr;
/*
* merge against previous area (if there is a previous
* area).
*/
if (pmn != &mp->mp_First) {
if ((char*)pmn + ((MemNode*)pmn)->mr_Bytes == (char*)ptr) {
((MemNode *)pmn)->mr_Next = mn->mr_Next;
((MemNode *)pmn)->mr_Bytes += mn->mr_Bytes;
mn = (MemNode *)pmn;
}
}
return;
/* NOT REACHED */
}
if ((char *)ptr < (char *)mn + mn->mr_Bytes) {
mp->mp_Panic("zfree(%s,0x%08lx,%d): corrupt memlist2",
mp->mp_Ident,
(long)ptr,
bytes
);
}
}
/*
* We are beyond the last MemNode, append new MemNode. Merge against
* previous area if possible.
*/
if (pmn == &mp->mp_First ||
(char *)pmn + ((MemNode *)pmn)->mr_Bytes != (char *)ptr
) {
((MemNode *)ptr)->mr_Next = NULL;
((MemNode *)ptr)->mr_Bytes = bytes;
*pmn = (MemNode *)ptr;
mn = (MemNode *)ptr;
} else {
((MemNode *)pmn)->mr_Bytes += bytes;
mn = (MemNode *)pmn;
}
}
}
#ifndef MALLOCLIB
/*
* zallocStr() - allocate memory and copy string.
*/
char *
zallocStr(MemPool *mp, const char *s, int slen)
{
char *ptr;
if (slen < 0)
slen = strlen(s);
if ((ptr = znalloc(mp, slen + 1)) != NULL) {
bcopy(s, ptr, slen);
ptr[slen] = 0;
}
return(ptr);
}
/*
* zfreeStr() - free memory associated with an allocated string.
*/
void
zfreeStr(MemPool *mp, char *s)
{
zfree(mp, s, strlen(s) + 1);
}
#endif
/*
* zinitpool() - initialize a memory pool
*/
void
zinitPool(
MemPool *mp,
const char *id,
void (*fpanic)(const char *ctl, ...),
int (*freclaim)(MemPool *memPool, iaddr_t bytes),
void *pBase,
iaddr_t pSize
) {
if (fpanic == NULL)
fpanic = znop;
if (freclaim == NULL)
freclaim = znot;
if (id != (const char *)-1)
mp->mp_Ident = id;
mp->mp_Base = pBase;
mp->mp_End = (char *)pBase + pSize;
mp->mp_First = NULL;
mp->mp_Size = pSize;
mp->mp_Used = pSize;
mp->mp_Panic = fpanic;
mp->mp_Reclaim = freclaim;
}
/*
* zextendPool() - extend memory pool to cover additional space.
*
* Note: the added memory starts out as allocated, you
* must free it to make it available to the memory subsystem.
*
* Note: mp_Size may not reflect (mp_End - mp_Base) range
* due to other parts of the system doing their own sbrk()
* calls.
*/
void
zextendPool(MemPool *mp, void *base, iaddr_t bytes)
{
if (mp->mp_Size == 0) {
mp->mp_Base = base;
mp->mp_Used = bytes;
mp->mp_End = (char *)base + bytes;
} else {
void *pend = (char *)mp->mp_Base + mp->mp_Size;
if (base < mp->mp_Base) {
/* mp->mp_Size += (char *)mp->mp_Base - (char *)base; */
mp->mp_Used += (char *)mp->mp_Base - (char *)base;
mp->mp_Base = base;
}
base = (char *)base + bytes;
if (base > pend) {
/* mp->mp_Size += (char *)base - (char *)pend; */
mp->mp_Used += (char *)base - (char *)pend;
mp->mp_End = (char *)base;
}
}
mp->mp_Size += bytes;
}
#ifndef MALLOCLIB
/*
* zclearpool() - Free all memory associated with a memory pool,
* destroying any previous allocations. Commonly
* called afte zinitPool() to make a pool available
* for use.
*/
void
zclearPool(MemPool *mp)
{
MemNode *mn = mp->mp_Base;
mn->mr_Next = NULL;
mn->mr_Bytes = mp->mp_Size;
mp->mp_First = mn;
}
#endif
#ifdef ZALLOCDEBUG
void
zallocstats(MemPool *mp)
{
int abytes = 0;
int hbytes = 0;
int fcount = 0;
MemNode *mn;
printf("Pool %s, %d bytes reserved", mp->mp_Ident, (int) mp->mp_Size);
mn = mp->mp_First;
if ((void *)mn != (void *)mp->mp_Base) {
abytes += (char *)mn - (char *)mp->mp_Base;
}
while (mn) {
if ((char *)mn + mn->mr_Bytes != mp->mp_End) {
hbytes += mn->mr_Bytes;
++fcount;
}
if (mn->mr_Next)
abytes += (char *)mn->mr_Next - ((char *)mn + mn->mr_Bytes);
mn = mn->mr_Next;
}
printf(" %d bytes allocated\n%d fragments (%d bytes fragmented)\n",
abytes,
fcount,
hbytes
);
}
#endif