xref: /titanic_41/usr/src/lib/libast/common/vmalloc/vmlast.c (revision 02d09e03eb27f3a2dc299de704e45dae5173f43f)
1 /***********************************************************************
2 *                                                                      *
3 *               This software is part of the ast package               *
4 *          Copyright (c) 1985-2009 AT&T Intellectual Property          *
5 *                      and is licensed under the                       *
6 *                  Common Public License, Version 1.0                  *
7 *                    by AT&T Intellectual Property                     *
8 *                                                                      *
9 *                A copy of the License is available at                 *
10 *            http://www.opensource.org/licenses/cpl1.0.txt             *
11 *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
12 *                                                                      *
13 *              Information and Software Systems Research               *
14 *                            AT&T Research                             *
15 *                           Florham Park NJ                            *
16 *                                                                      *
17 *                 Glenn Fowler <gsf@research.att.com>                  *
18 *                  David Korn <dgk@research.att.com>                   *
19 *                   Phong Vo <kpv@research.att.com>                    *
20 *                                                                      *
21 ***********************************************************************/
22 #if defined(_UWIN) && defined(_BLD_ast)
23 
24 void _STUB_vmlast(){}
25 
26 #else
27 
28 #include	"vmhdr.h"
29 
30 /*	Allocation with freeing and reallocing of last allocated block only.
31 **
32 **	Written by Kiem-Phong Vo, kpv@research.att.com, 01/16/94.
33 */
34 
35 #if __STD_C
36 static Void_t* lastalloc(Vmalloc_t* vm, size_t size)
37 #else
38 static Void_t* lastalloc(vm, size)
39 Vmalloc_t*	vm;
40 size_t		size;
41 #endif
42 {
43 	reg Block_t	*tp, *next;
44 	reg Seg_t	*seg, *last;
45 	reg size_t	s;
46 	reg Vmdata_t*	vd = vm->data;
47 	reg int		local, inuse;
48 	size_t		orgsize = 0;
49 
50 	SETINUSE(vd, inuse);
51 	if(!(local = vd->mode&VM_TRUST))
52 	{	GETLOCAL(vd,local);
53 		if(ISLOCK(vd,local))
54 		{	CLRINUSE(vd, inuse);
55 			return NIL(Void_t*);
56 		}
57 		SETLOCK(vd,local);
58 		orgsize = size;
59 	}
60 
61 	size = size < ALIGN ? ALIGN : ROUND(size,ALIGN);
62 	for(;;)
63 	{	for(last = NIL(Seg_t*), seg = vd->seg; seg; last = seg, seg = seg->next)
64 		{	if(!(tp = seg->free) || (SIZE(tp)+sizeof(Head_t)) < size)
65 				continue;
66 			if(last)
67 			{	last->next = seg->next;
68 				seg->next = vd->seg;
69 				vd->seg = seg;
70 			}
71 			goto got_block;
72 		}
73 
74 		/* there is no usable free space in region, try extending */
75 		if((tp = (*_Vmextend)(vm,size,NIL(Vmsearch_f))) )
76 		{	seg = SEG(tp);
77 			goto got_block;
78 		}
79 		else if(vd->mode&VM_AGAIN)
80 			vd->mode &= ~VM_AGAIN;
81 		else	goto done;
82 	}
83 
84 got_block:
85 	if((s = SIZE(tp)) >= size)
86 	{	next = (Block_t*)((Vmuchar_t*)tp+size);
87 		SIZE(next) = s - size;
88 		SEG(next) = seg;
89 		seg->free = next;
90 	}
91 	else	seg->free = NIL(Block_t*);
92 
93 	vd->free = seg->last = tp;
94 
95 	if(!local && (vd->mode&VM_TRACE) && _Vmtrace)
96 		(*_Vmtrace)(vm, NIL(Vmuchar_t*), (Vmuchar_t*)tp, orgsize, 0);
97 
98 done:
99 	CLRLOCK(vd,local);
100 	ANNOUNCE(local, vm, VM_ALLOC, (Void_t*)tp, vm->disc);
101 	CLRINUSE(vd, inuse);
102 	return (Void_t*)tp;
103 }
104 
105 #if __STD_C
106 static int lastfree(Vmalloc_t* vm, reg Void_t* data )
107 #else
108 static int lastfree(vm, data)
109 Vmalloc_t*	vm;
110 reg Void_t*	data;
111 #endif
112 {
113 	reg Seg_t*	seg;
114 	reg Block_t*	fp;
115 	reg size_t	s;
116 	reg Vmdata_t*	vd = vm->data;
117 	reg int		local, inuse;
118 
119 	if(!data)
120 		return 0;
121 
122 	SETINUSE(vd, inuse);
123 	if(!(local = vd->mode&VM_TRUST) )
124 	{	GETLOCAL(vd, local);
125 		if(ISLOCK(vd, local))
126 		{	CLRINUSE(vd, inuse);
127 			return -1;
128 		}
129 		SETLOCK(vd, local);
130 	}
131 	if(data != (Void_t*)vd->free)
132 	{	if(!local && vm->disc->exceptf)
133 			(void)(*vm->disc->exceptf)(vm,VM_BADADDR,data,vm->disc);
134 		CLRLOCK(vd, local);
135 		CLRINUSE(vd, inuse);
136 		return -1;
137 	}
138 
139 	seg = vd->seg;
140 	if(!local && (vd->mode&VM_TRACE) && _Vmtrace)
141 	{	if(seg->free )
142 			s = (Vmuchar_t*)(seg->free) - (Vmuchar_t*)data;
143 		else	s = (Vmuchar_t*)BLOCK(seg->baddr) - (Vmuchar_t*)data;
144 		(*_Vmtrace)(vm, (Vmuchar_t*)data, NIL(Vmuchar_t*), s, 0);
145 	}
146 
147 	vd->free = NIL(Block_t*);
148 	fp = (Block_t*)data;
149 	SEG(fp)  = seg;
150 	SIZE(fp) = ((Vmuchar_t*)BLOCK(seg->baddr) - (Vmuchar_t*)data) - sizeof(Head_t);
151 	seg->free = fp;
152 	seg->last = NIL(Block_t*);
153 
154 	CLRLOCK(vd, local);
155 	ANNOUNCE(local, vm, VM_FREE, data, vm->disc);
156 
157 	CLRINUSE(vd, inuse);
158 	return 0;
159 }
160 
161 #if __STD_C
162 static Void_t* lastresize(Vmalloc_t* vm, reg Void_t* data, size_t size, int type )
163 #else
164 static Void_t* lastresize(vm, data, size, type )
165 Vmalloc_t*	vm;
166 reg Void_t*	data;
167 size_t		size;
168 int		type;
169 #endif
170 {
171 	reg Block_t*	tp;
172 	reg Seg_t	*seg;
173 	reg size_t	oldsize;
174 	reg ssize_t	s, ds;
175 	reg Vmdata_t*	vd = vm->data;
176 	reg int		local, inuse;
177 	reg Void_t*	addr;
178 	Void_t*		orgdata = NIL(Void_t*);
179 	size_t		orgsize = 0;
180 
181 	SETINUSE(vd, inuse);
182 	if(!data)
183 	{	oldsize = 0;
184 		data = lastalloc(vm,size);
185 		goto done;
186 	}
187 	if(size <= 0)
188 	{	(void)lastfree(vm,data);
189 		CLRINUSE(vd, inuse);
190 		return NIL(Void_t*);
191 	}
192 
193 	if(!(local = vd->mode&VM_TRUST))
194 	{	GETLOCAL(vd, local);
195 		if(ISLOCK(vd, local))
196 		{	CLRINUSE(vd, inuse);
197 			return NIL(Void_t*);
198 		}
199 		SETLOCK(vd, local);
200 		orgdata = data;
201 		orgsize = size;
202 	}
203 
204 	if(data == (Void_t*)vd->free)
205 		seg = vd->seg;
206 	else
207 	{	/* see if it was one of ours */
208 		for(seg = vd->seg; seg; seg = seg->next)
209 			if(data >= seg->addr && data < (Void_t*)seg->baddr)
210 				break;
211 		if(!seg || (VLONG(data)%ALIGN) != 0 ||
212 		   (seg->last && (Vmuchar_t*)data > (Vmuchar_t*)seg->last) )
213 		{	CLRLOCK(vd,0);
214 			CLRINUSE(vd, inuse);
215 			return NIL(Void_t*);
216 		}
217 	}
218 
219 	/* set 's' to be the current available space */
220 	if(data != seg->last)
221 	{	if(seg->last && (Vmuchar_t*)data < (Vmuchar_t*)seg->last)
222 			oldsize = (Vmuchar_t*)seg->last - (Vmuchar_t*)data;
223 		else	oldsize = (Vmuchar_t*)BLOCK(seg->baddr) - (Vmuchar_t*)data;
224 		s = -1;
225 	}
226 	else
227 	{	s = (Vmuchar_t*)BLOCK(seg->baddr) - (Vmuchar_t*)data;
228 		if(!(tp = seg->free) )
229 			oldsize = s;
230 		else
231 		{	oldsize = (Vmuchar_t*)tp - (Vmuchar_t*)data;
232 			seg->free = NIL(Block_t*);
233 		}
234 	}
235 
236 	size = size < ALIGN ? ALIGN : ROUND(size,ALIGN);
237 	if(s < 0 || (ssize_t)size > s)
238 	{	if(s >= 0) /* amount to extend */
239 		{	ds = size-s; ds = ROUND(ds,vd->incr);
240 			addr = (*vm->disc->memoryf)(vm, seg->addr, seg->extent,
241 						    seg->extent+ds, vm->disc);
242 			if(addr == seg->addr)
243 			{	s += ds;
244 				seg->size += ds;
245 				seg->extent += ds;
246 				seg->baddr += ds;
247 				SIZE(BLOCK(seg->baddr)) = BUSY;
248 			}
249 			else	goto do_alloc;
250 		}
251 		else
252 		{ do_alloc:
253 			if(!(type&(VM_RSMOVE|VM_RSCOPY)) )
254 				data = NIL(Void_t*);
255 			else
256 			{	tp = vd->free;
257 				if(!(addr = KPVALLOC(vm,size,lastalloc)) )
258 				{	vd->free = tp;
259 					data = NIL(Void_t*);
260 				}
261 				else
262 				{	if(type&VM_RSCOPY)
263 					{	ds = oldsize < size ? oldsize : size;
264 						memcpy(addr, data, ds);
265 					}
266 
267 					if(s >= 0 && seg != vd->seg)
268 					{	tp = (Block_t*)data;
269 						SEG(tp) = seg;
270 						SIZE(tp) = s - sizeof(Head_t);
271 						seg->free = tp;
272 					}
273 
274 					/* new block and size */
275 					data = addr;
276 					seg = vd->seg;
277 					s = (Vmuchar_t*)BLOCK(seg->baddr) -
278 					    (Vmuchar_t*)data;
279 					seg->free = NIL(Block_t*);
280 				}
281 			}
282 		}
283 	}
284 
285 	if(data)
286 	{	if(s >= (ssize_t)(size+sizeof(Head_t)) )
287 		{	tp = (Block_t*)((Vmuchar_t*)data + size);
288 			SEG(tp) = seg;
289 			SIZE(tp) = (s - size) - sizeof(Head_t);
290 			seg->free = tp;
291 		}
292 
293 		vd->free = seg->last = (Block_t*)data;
294 
295 		if(!local && (vd->mode&VM_TRACE) && _Vmtrace)
296 			(*_Vmtrace)(vm,(Vmuchar_t*)orgdata,(Vmuchar_t*)data,orgsize,0);
297 	}
298 
299 	CLRLOCK(vd, local);
300 	ANNOUNCE(local, vm, VM_RESIZE, data, vm->disc);
301 
302 done:	if(data && (type&VM_RSZERO) && size > oldsize)
303 		memset((Void_t*)((Vmuchar_t*)data + oldsize), 0, size-oldsize);
304 
305 	CLRINUSE(vd, inuse);
306 	return data;
307 }
308 
309 
310 #if __STD_C
311 static long lastaddr(Vmalloc_t* vm, Void_t* addr)
312 #else
313 static long lastaddr(vm, addr)
314 Vmalloc_t*	vm;
315 Void_t*		addr;
316 #endif
317 {
318 	reg Vmdata_t*	vd = vm->data;
319 
320 	if(!(vd->mode&VM_TRUST) && ISLOCK(vd,0))
321 		return -1L;
322 	if(!vd->free || addr < (Void_t*)vd->free || addr >= (Void_t*)vd->seg->baddr)
323 		return -1L;
324 	else	return (Vmuchar_t*)addr - (Vmuchar_t*)vd->free;
325 }
326 
327 #if __STD_C
328 static long lastsize(Vmalloc_t* vm, Void_t* addr)
329 #else
330 static long lastsize(vm, addr)
331 Vmalloc_t*	vm;
332 Void_t*		addr;
333 #endif
334 {
335 	reg Vmdata_t*	vd = vm->data;
336 
337 	if(!(vd->mode&VM_TRUST) && ISLOCK(vd,0))
338 		return -1L;
339 	if(!vd->free || addr != (Void_t*)vd->free )
340 		return -1L;
341 	else if(vd->seg->free)
342 		return (Vmuchar_t*)vd->seg->free - (Vmuchar_t*)addr;
343 	else	return (Vmuchar_t*)vd->seg->baddr - (Vmuchar_t*)addr - sizeof(Head_t);
344 }
345 
346 #if __STD_C
347 static int lastcompact(Vmalloc_t* vm)
348 #else
349 static int lastcompact(vm)
350 Vmalloc_t*	vm;
351 #endif
352 {
353 	reg Block_t*	fp;
354 	reg Seg_t	*seg, *next;
355 	reg size_t	s;
356 	reg Vmdata_t*	vd = vm->data;
357 	reg int		inuse;
358 
359 	SETINUSE(vd, inuse);
360 	if(!(vd->mode&VM_TRUST))
361 	{	if(ISLOCK(vd,0))
362 		{	CLRINUSE(vd, inuse);
363 			return -1;
364 		}
365 		SETLOCK(vd,0);
366 	}
367 
368 	for(seg = vd->seg; seg; seg = next)
369 	{	next = seg->next;
370 
371 		if(!(fp = seg->free))
372 			continue;
373 
374 		seg->free = NIL(Block_t*);
375 		if(seg->size == (s = SIZE(fp)&~BITS))
376 			s = seg->extent;
377 		else	s += sizeof(Head_t);
378 
379 		if((*_Vmtruncate)(vm,seg,s,1) == s)
380 			seg->free = fp;
381 	}
382 
383 	if((vd->mode&VM_TRACE) && _Vmtrace)
384 		(*_Vmtrace)(vm,(Vmuchar_t*)0,(Vmuchar_t*)0,0,0);
385 
386 	CLRLOCK(vd,0);
387 	CLRINUSE(vd, inuse);
388 	return 0;
389 }
390 
391 #if __STD_C
392 static Void_t* lastalign(Vmalloc_t* vm, size_t size, size_t align)
393 #else
394 static Void_t* lastalign(vm, size, align)
395 Vmalloc_t*	vm;
396 size_t		size;
397 size_t		align;
398 #endif
399 {
400 	reg Vmuchar_t*	data;
401 	reg Seg_t*	seg;
402 	reg Block_t*	next;
403 	reg int		local, inuse;
404 	reg size_t	s, orgsize = 0, orgalign = 0;
405 	reg Vmdata_t*	vd = vm->data;
406 
407 	if(size <= 0 || align <= 0)
408 		return NIL(Void_t*);
409 
410 	SETINUSE(vd, inuse);
411 	if(!(local = vd->mode&VM_TRUST) )
412 	{	GETLOCAL(vd,local);
413 		if(ISLOCK(vd,local) )
414 		{	CLRINUSE(vd, inuse);
415 			return NIL(Void_t*);
416 		}
417 		SETLOCK(vd,local);
418 		orgsize = size;
419 		orgalign = align;
420 	}
421 
422 	size = size <= TINYSIZE ? TINYSIZE : ROUND(size,ALIGN);
423 	align = MULTIPLE(align,ALIGN);
424 
425 	s = size + align;
426 	if(!(data = (Vmuchar_t*)KPVALLOC(vm,s,lastalloc)) )
427 		goto done;
428 
429 	/* find the segment containing this block */
430 	for(seg = vd->seg; seg; seg = seg->next)
431 		if(seg->last == (Block_t*)data)
432 			break;
433 	/**/ASSERT(seg);
434 
435 	/* get a suitably aligned address */
436 	if((s = (size_t)(VLONG(data)%align)) != 0)
437 		data += align-s; /**/ASSERT((VLONG(data)%align) == 0);
438 
439 	/* free the unused tail */
440 	next = (Block_t*)(data+size);
441 	if((s = (seg->baddr - (Vmuchar_t*)next)) >= sizeof(Block_t))
442 	{	SEG(next) = seg;
443 		SIZE(next) = s - sizeof(Head_t);
444 		seg->free = next;
445 	}
446 
447 	vd->free = seg->last = (Block_t*)data;
448 
449 	if(!local && !(vd->mode&VM_TRUST) && _Vmtrace && (vd->mode&VM_TRACE) )
450 		(*_Vmtrace)(vm,NIL(Vmuchar_t*),data,orgsize,orgalign);
451 
452 done:
453 	CLRLOCK(vd,local);
454 	ANNOUNCE(local, vm, VM_ALLOC, (Void_t*)data, vm->disc);
455 
456 	CLRINUSE(vd, inuse);
457 	return (Void_t*)data;
458 }
459 
460 /* Public method for free-1 allocation */
461 static Vmethod_t _Vmlast =
462 {
463 	lastalloc,
464 	lastresize,
465 	lastfree,
466 	lastaddr,
467 	lastsize,
468 	lastcompact,
469 	lastalign,
470 	VM_MTLAST
471 };
472 
473 __DEFINE__(Vmethod_t*,Vmlast,&_Vmlast);
474 
475 #ifdef NoF
476 NoF(vmlast)
477 #endif
478 
479 #endif
480