1 056fe1ba 2003-11-23 devnull #include <u.h>
 2 056fe1ba 2003-11-23 devnull #include <libc.h>
 3 056fe1ba 2003-11-23 devnull #include <venti.h>
 4 056fe1ba 2003-11-23 devnull 
 5 056fe1ba 2003-11-23 devnull enum {
 6 056fe1ba 2003-11-23 devnull 	IdealAlignment = 32,
 7 056fe1ba 2003-11-23 devnull 	ChunkSize 	= 128*1024,
 8 056fe1ba 2003-11-23 devnull };
 9 056fe1ba 2003-11-23 devnull 
10 056fe1ba 2003-11-23 devnull 
11 056fe1ba 2003-11-23 devnull void
12 056fe1ba 2003-11-23 devnull vtfree(void *p)
13 056fe1ba 2003-11-23 devnull {
14 056fe1ba 2003-11-23 devnull 	if(p == 0)
15 056fe1ba 2003-11-23 devnull 		return;
16 056fe1ba 2003-11-23 devnull 	free(p);
17 056fe1ba 2003-11-23 devnull }
18 056fe1ba 2003-11-23 devnull 
19 056fe1ba 2003-11-23 devnull void *
20 056fe1ba 2003-11-23 devnull vtmalloc(int size)
21 056fe1ba 2003-11-23 devnull {
22 056fe1ba 2003-11-23 devnull 	void *p;
23 056fe1ba 2003-11-23 devnull 
24 056fe1ba 2003-11-23 devnull 	p = malloc(size);
25 056fe1ba 2003-11-23 devnull 	if(p == 0)
26 056fe1ba 2003-11-23 devnull 		sysfatal("vtmalloc: out of memory");
27 056fe1ba 2003-11-23 devnull 	setmalloctag(p, getcallerpc(&size));
28 056fe1ba 2003-11-23 devnull 	return p;
29 056fe1ba 2003-11-23 devnull }
30 056fe1ba 2003-11-23 devnull 
31 056fe1ba 2003-11-23 devnull void *
32 056fe1ba 2003-11-23 devnull vtmallocz(int size)
33 056fe1ba 2003-11-23 devnull {
34 056fe1ba 2003-11-23 devnull 	void *p = vtmalloc(size);
35 056fe1ba 2003-11-23 devnull 	memset(p, 0, size);
36 056fe1ba 2003-11-23 devnull 	setmalloctag(p, getcallerpc(&size));
37 056fe1ba 2003-11-23 devnull 	return p;
38 056fe1ba 2003-11-23 devnull }
39 056fe1ba 2003-11-23 devnull 
40 056fe1ba 2003-11-23 devnull void *
41 056fe1ba 2003-11-23 devnull vtrealloc(void *p, int size)
42 056fe1ba 2003-11-23 devnull {
43 056fe1ba 2003-11-23 devnull 	if(p == nil)
44 056fe1ba 2003-11-23 devnull 		return vtmalloc(size);
45 056fe1ba 2003-11-23 devnull 	p = realloc(p, size);
46 056fe1ba 2003-11-23 devnull 	if(p == 0)
47 056fe1ba 2003-11-23 devnull 		sysfatal("vtMemRealloc: out of memory");
48 056fe1ba 2003-11-23 devnull 	setrealloctag(p, getcallerpc(&size));
49 056fe1ba 2003-11-23 devnull 	return p;
50 056fe1ba 2003-11-23 devnull }
51 056fe1ba 2003-11-23 devnull 
52 056fe1ba 2003-11-23 devnull void *
53 056fe1ba 2003-11-23 devnull vtbrk(int n)
54 056fe1ba 2003-11-23 devnull {
55 056fe1ba 2003-11-23 devnull 	static Lock lk;
56 056fe1ba 2003-11-23 devnull 	static uchar *buf;
57 056fe1ba 2003-11-23 devnull 	static int nbuf;
58 056fe1ba 2003-11-23 devnull 	static int nchunk;
59 056fe1ba 2003-11-23 devnull 	int align, pad;
60 056fe1ba 2003-11-23 devnull 	void *p;
61 056fe1ba 2003-11-23 devnull 
62 056fe1ba 2003-11-23 devnull 	if(n >= IdealAlignment)
63 056fe1ba 2003-11-23 devnull 		align = IdealAlignment;
64 056fe1ba 2003-11-23 devnull 	else if(n > 8)
65 056fe1ba 2003-11-23 devnull 		align = 8;
66 056fe1ba 2003-11-23 devnull 	else	
67 056fe1ba 2003-11-23 devnull 		align = 4;
68 056fe1ba 2003-11-23 devnull 
69 056fe1ba 2003-11-23 devnull 	lock(&lk);
70 056fe1ba 2003-11-23 devnull 	pad = (align - (ulong)buf) & (align-1);
71 056fe1ba 2003-11-23 devnull 	if(n + pad > nbuf) {
72 056fe1ba 2003-11-23 devnull 		buf = vtmallocz(ChunkSize);
73 056fe1ba 2003-11-23 devnull 		nbuf = ChunkSize;
74 056fe1ba 2003-11-23 devnull 		pad = (align - (ulong)buf) & (align-1);
75 056fe1ba 2003-11-23 devnull 		nchunk++;
76 056fe1ba 2003-11-23 devnull 	}
77 056fe1ba 2003-11-23 devnull 
78 056fe1ba 2003-11-23 devnull 	assert(n + pad <= nbuf);	
79 056fe1ba 2003-11-23 devnull 	
80 056fe1ba 2003-11-23 devnull 	p = buf + pad;
81 056fe1ba 2003-11-23 devnull 	buf += pad + n;
82 056fe1ba 2003-11-23 devnull 	nbuf -= pad + n;
83 056fe1ba 2003-11-23 devnull 	unlock(&lk);
84 056fe1ba 2003-11-23 devnull 
85 056fe1ba 2003-11-23 devnull 	return p;
86 056fe1ba 2003-11-23 devnull }
87 056fe1ba 2003-11-23 devnull