vmlast.c revision 34f9b3eef6fdadbda0a846aa4d68691ac40eace5
/***********************************************************************
* *
* This software is part of the ast package *
* Copyright (c) 1985-2009 AT&T Intellectual Property *
* and is licensed under the *
* Common Public License, Version 1.0 *
* by AT&T Intellectual Property *
* *
* A copy of the License is available at *
* http://www.opensource.org/licenses/cpl1.0.txt *
* (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9) *
* *
* Information and Software Systems Research *
* AT&T Research *
* Florham Park NJ *
* *
* Glenn Fowler <gsf@research.att.com> *
* David Korn <dgk@research.att.com> *
* Phong Vo <kpv@research.att.com> *
* *
***********************************************************************/
#if defined(_UWIN) && defined(_BLD_ast)
void _STUB_vmlast(){}
#else
#include "vmhdr.h"
/* Allocation with freeing and reallocing of last allocated block only.
**
** Written by Kiem-Phong Vo, kpv@research.att.com, 01/16/94.
*/
#if __STD_C
static Void_t* lastalloc(Vmalloc_t* vm, size_t size)
#else
static Void_t* lastalloc(vm, size)
Vmalloc_t* vm;
size_t size;
#endif
{
reg Block_t *tp, *next;
reg Seg_t *seg, *last;
reg size_t s;
reg Vmdata_t* vd = vm->data;
reg int local, inuse;
size_t orgsize = 0;
SETINUSE(vd, inuse);
if(!(local = vd->mode&VM_TRUST))
{ GETLOCAL(vd,local);
if(ISLOCK(vd,local))
{ CLRINUSE(vd, inuse);
return NIL(Void_t*);
}
SETLOCK(vd,local);
orgsize = size;
}
size = size < ALIGN ? ALIGN : ROUND(size,ALIGN);
for(;;)
{ for(last = NIL(Seg_t*), seg = vd->seg; seg; last = seg, seg = seg->next)
{ if(!(tp = seg->free) || (SIZE(tp)+sizeof(Head_t)) < size)
continue;
if(last)
{ last->next = seg->next;
seg->next = vd->seg;
vd->seg = seg;
}
goto got_block;
}
/* there is no usable free space in region, try extending */
if((tp = (*_Vmextend)(vm,size,NIL(Vmsearch_f))) )
{ seg = SEG(tp);
goto got_block;
}
else if(vd->mode&VM_AGAIN)
vd->mode &= ~VM_AGAIN;
else goto done;
}
got_block:
if((s = SIZE(tp)) >= size)
{ next = (Block_t*)((Vmuchar_t*)tp+size);
SIZE(next) = s - size;
SEG(next) = seg;
seg->free = next;
}
else seg->free = NIL(Block_t*);
vd->free = seg->last = tp;
if(!local && (vd->mode&VM_TRACE) && _Vmtrace)
(*_Vmtrace)(vm, NIL(Vmuchar_t*), (Vmuchar_t*)tp, orgsize, 0);
done:
CLRLOCK(vd,local);
ANNOUNCE(local, vm, VM_ALLOC, (Void_t*)tp, vm->disc);
CLRINUSE(vd, inuse);
return (Void_t*)tp;
}
#if __STD_C
static int lastfree(Vmalloc_t* vm, reg Void_t* data )
#else
static int lastfree(vm, data)
Vmalloc_t* vm;
reg Void_t* data;
#endif
{
reg Seg_t* seg;
reg Block_t* fp;
reg size_t s;
reg Vmdata_t* vd = vm->data;
reg int local, inuse;
if(!data)
return 0;
SETINUSE(vd, inuse);
if(!(local = vd->mode&VM_TRUST) )
{ GETLOCAL(vd, local);
if(ISLOCK(vd, local))
{ CLRINUSE(vd, inuse);
return -1;
}
SETLOCK(vd, local);
}
if(data != (Void_t*)vd->free)
{ if(!local && vm->disc->exceptf)
(void)(*vm->disc->exceptf)(vm,VM_BADADDR,data,vm->disc);
CLRLOCK(vd, local);
CLRINUSE(vd, inuse);
return -1;
}
seg = vd->seg;
if(!local && (vd->mode&VM_TRACE) && _Vmtrace)
{ if(seg->free )
s = (Vmuchar_t*)(seg->free) - (Vmuchar_t*)data;
else s = (Vmuchar_t*)BLOCK(seg->baddr) - (Vmuchar_t*)data;
(*_Vmtrace)(vm, (Vmuchar_t*)data, NIL(Vmuchar_t*), s, 0);
}
vd->free = NIL(Block_t*);
fp = (Block_t*)data;
SEG(fp) = seg;
SIZE(fp) = ((Vmuchar_t*)BLOCK(seg->baddr) - (Vmuchar_t*)data) - sizeof(Head_t);
seg->free = fp;
seg->last = NIL(Block_t*);
CLRLOCK(vd, local);
ANNOUNCE(local, vm, VM_FREE, data, vm->disc);
CLRINUSE(vd, inuse);
return 0;
}
#if __STD_C
static Void_t* lastresize(Vmalloc_t* vm, reg Void_t* data, size_t size, int type )
#else
static Void_t* lastresize(vm, data, size, type )
Vmalloc_t* vm;
reg Void_t* data;
size_t size;
int type;
#endif
{
reg Block_t* tp;
reg Seg_t *seg;
reg size_t oldsize;
reg ssize_t s, ds;
reg Vmdata_t* vd = vm->data;
reg int local, inuse;
reg Void_t* addr;
Void_t* orgdata = NIL(Void_t*);
size_t orgsize = 0;
SETINUSE(vd, inuse);
if(!data)
{ oldsize = 0;
data = lastalloc(vm,size);
goto done;
}
if(size <= 0)
{ (void)lastfree(vm,data);
CLRINUSE(vd, inuse);
return NIL(Void_t*);
}
if(!(local = vd->mode&VM_TRUST))
{ GETLOCAL(vd, local);
if(ISLOCK(vd, local))
{ CLRINUSE(vd, inuse);
return NIL(Void_t*);
}
SETLOCK(vd, local);
orgdata = data;
orgsize = size;
}
if(data == (Void_t*)vd->free)
seg = vd->seg;
else
{ /* see if it was one of ours */
for(seg = vd->seg; seg; seg = seg->next)
if(data >= seg->addr && data < (Void_t*)seg->baddr)
break;
if(!seg || (VLONG(data)%ALIGN) != 0 ||
(seg->last && (Vmuchar_t*)data > (Vmuchar_t*)seg->last) )
{ CLRLOCK(vd,0);
CLRINUSE(vd, inuse);
return NIL(Void_t*);
}
}
/* set 's' to be the current available space */
if(data != seg->last)
{ if(seg->last && (Vmuchar_t*)data < (Vmuchar_t*)seg->last)
oldsize = (Vmuchar_t*)seg->last - (Vmuchar_t*)data;
else oldsize = (Vmuchar_t*)BLOCK(seg->baddr) - (Vmuchar_t*)data;
s = -1;
}
else
{ s = (Vmuchar_t*)BLOCK(seg->baddr) - (Vmuchar_t*)data;
if(!(tp = seg->free) )
oldsize = s;
else
{ oldsize = (Vmuchar_t*)tp - (Vmuchar_t*)data;
seg->free = NIL(Block_t*);
}
}
size = size < ALIGN ? ALIGN : ROUND(size,ALIGN);
if(s < 0 || (ssize_t)size > s)
{ if(s >= 0) /* amount to extend */
{ ds = size-s; ds = ROUND(ds,vd->incr);
addr = (*vm->disc->memoryf)(vm, seg->addr, seg->extent,
seg->extent+ds, vm->disc);
if(addr == seg->addr)
{ s += ds;
seg->size += ds;
seg->extent += ds;
seg->baddr += ds;
SIZE(BLOCK(seg->baddr)) = BUSY;
}
else goto do_alloc;
}
else
{ do_alloc:
if(!(type&(VM_RSMOVE|VM_RSCOPY)) )
data = NIL(Void_t*);
else
{ tp = vd->free;
if(!(addr = KPVALLOC(vm,size,lastalloc)) )
{ vd->free = tp;
data = NIL(Void_t*);
}
else
{ if(type&VM_RSCOPY)
{ ds = oldsize < size ? oldsize : size;
memcpy(addr, data, ds);
}
if(s >= 0 && seg != vd->seg)
{ tp = (Block_t*)data;
SEG(tp) = seg;
SIZE(tp) = s - sizeof(Head_t);
seg->free = tp;
}
/* new block and size */
data = addr;
seg = vd->seg;
s = (Vmuchar_t*)BLOCK(seg->baddr) -
(Vmuchar_t*)data;
seg->free = NIL(Block_t*);
}
}
}
}
if(data)
{ if(s >= (ssize_t)(size+sizeof(Head_t)) )
{ tp = (Block_t*)((Vmuchar_t*)data + size);
SEG(tp) = seg;
SIZE(tp) = (s - size) - sizeof(Head_t);
seg->free = tp;
}
vd->free = seg->last = (Block_t*)data;
if(!local && (vd->mode&VM_TRACE) && _Vmtrace)
(*_Vmtrace)(vm,(Vmuchar_t*)orgdata,(Vmuchar_t*)data,orgsize,0);
}
CLRLOCK(vd, local);
ANNOUNCE(local, vm, VM_RESIZE, data, vm->disc);
done: if(data && (type&VM_RSZERO) && size > oldsize)
memset((Void_t*)((Vmuchar_t*)data + oldsize), 0, size-oldsize);
CLRINUSE(vd, inuse);
return data;
}
#if __STD_C
static long lastaddr(Vmalloc_t* vm, Void_t* addr)
#else
static long lastaddr(vm, addr)
Vmalloc_t* vm;
Void_t* addr;
#endif
{
reg Vmdata_t* vd = vm->data;
if(!(vd->mode&VM_TRUST) && ISLOCK(vd,0))
return -1L;
if(!vd->free || addr < (Void_t*)vd->free || addr >= (Void_t*)vd->seg->baddr)
return -1L;
else return (Vmuchar_t*)addr - (Vmuchar_t*)vd->free;
}
#if __STD_C
static long lastsize(Vmalloc_t* vm, Void_t* addr)
#else
static long lastsize(vm, addr)
Vmalloc_t* vm;
Void_t* addr;
#endif
{
reg Vmdata_t* vd = vm->data;
if(!(vd->mode&VM_TRUST) && ISLOCK(vd,0))
return -1L;
if(!vd->free || addr != (Void_t*)vd->free )
return -1L;
else if(vd->seg->free)
return (Vmuchar_t*)vd->seg->free - (Vmuchar_t*)addr;
else return (Vmuchar_t*)vd->seg->baddr - (Vmuchar_t*)addr - sizeof(Head_t);
}
#if __STD_C
static int lastcompact(Vmalloc_t* vm)
#else
static int lastcompact(vm)
Vmalloc_t* vm;
#endif
{
reg Block_t* fp;
reg Seg_t *seg, *next;
reg size_t s;
reg Vmdata_t* vd = vm->data;
reg int inuse;
SETINUSE(vd, inuse);
if(!(vd->mode&VM_TRUST))
{ if(ISLOCK(vd,0))
{ CLRINUSE(vd, inuse);
return -1;
}
SETLOCK(vd,0);
}
for(seg = vd->seg; seg; seg = next)
{ next = seg->next;
if(!(fp = seg->free))
continue;
seg->free = NIL(Block_t*);
if(seg->size == (s = SIZE(fp)&~BITS))
s = seg->extent;
else s += sizeof(Head_t);
if((*_Vmtruncate)(vm,seg,s,1) == s)
seg->free = fp;
}
if((vd->mode&VM_TRACE) && _Vmtrace)
(*_Vmtrace)(vm,(Vmuchar_t*)0,(Vmuchar_t*)0,0,0);
CLRLOCK(vd,0);
CLRINUSE(vd, inuse);
return 0;
}
#if __STD_C
static Void_t* lastalign(Vmalloc_t* vm, size_t size, size_t align)
#else
static Void_t* lastalign(vm, size, align)
Vmalloc_t* vm;
size_t size;
size_t align;
#endif
{
reg Vmuchar_t* data;
reg Seg_t* seg;
reg Block_t* next;
reg int local, inuse;
reg size_t s, orgsize = 0, orgalign = 0;
reg Vmdata_t* vd = vm->data;
if(size <= 0 || align <= 0)
return NIL(Void_t*);
SETINUSE(vd, inuse);
if(!(local = vd->mode&VM_TRUST) )
{ GETLOCAL(vd,local);
if(ISLOCK(vd,local) )
{ CLRINUSE(vd, inuse);
return NIL(Void_t*);
}
SETLOCK(vd,local);
orgsize = size;
orgalign = align;
}
size = size <= TINYSIZE ? TINYSIZE : ROUND(size,ALIGN);
align = MULTIPLE(align,ALIGN);
s = size + align;
if(!(data = (Vmuchar_t*)KPVALLOC(vm,s,lastalloc)) )
goto done;
/* find the segment containing this block */
for(seg = vd->seg; seg; seg = seg->next)
if(seg->last == (Block_t*)data)
break;
/**/ASSERT(seg);
/* get a suitably aligned address */
if((s = (size_t)(VLONG(data)%align)) != 0)
data += align-s; /**/ASSERT((VLONG(data)%align) == 0);
/* free the unused tail */
next = (Block_t*)(data+size);
if((s = (seg->baddr - (Vmuchar_t*)next)) >= sizeof(Block_t))
{ SEG(next) = seg;
SIZE(next) = s - sizeof(Head_t);
seg->free = next;
}
vd->free = seg->last = (Block_t*)data;
if(!local && !(vd->mode&VM_TRUST) && _Vmtrace && (vd->mode&VM_TRACE) )
(*_Vmtrace)(vm,NIL(Vmuchar_t*),data,orgsize,orgalign);
done:
CLRLOCK(vd,local);
ANNOUNCE(local, vm, VM_ALLOC, (Void_t*)data, vm->disc);
CLRINUSE(vd, inuse);
return (Void_t*)data;
}
/* Public method for free-1 allocation */
static Vmethod_t _Vmlast =
{
lastalloc,
lastresize,
lastfree,
lastaddr,
lastsize,
lastcompact,
lastalign,
VM_MTLAST
};
__DEFINE__(Vmethod_t*,Vmlast,&_Vmlast);
#ifdef NoF
NoF(vmlast)
#endif
#endif