Warning: Attempt to read property "date" on null in /usr/local/www/websvn.planix.org/blame.php on line 247

Warning: Attempt to read property "msg" on null in /usr/local/www/websvn.planix.org/blame.php on line 247
WebSVN – planix.SVN – Blame – /os/branches/feature_tlsv12/sys/src/cmd/ext2srv/iobuf.c – Rev 2

Subversion Repositories planix.SVN

Rev

Go to most recent revision | Details | Last modification | View Log | RSS feed

Rev Author Line No. Line
2 - 1 
#include <u.h>
2 
#include <libc.h>
3 
#include <fcall.h>
4 
#include <thread.h>
5 
#include <9p.h>
6 
#include "dat.h"
7 
#include "fns.h"
8 
 
9 
#define	NIOBUF		100
10 
#define	HIOB		(NIOBUF/3)
11 
 
12 
static Iobuf*	hiob[HIOB];		/* hash buckets */
13 
static Iobuf	iobuf[NIOBUF];		/* buffer headers */
14 
static Iobuf*	iohead;
15 
static Iobuf*	iotail;
16 
 
17 
Iobuf*
18 
getbuf(Xfs *dev, long addr)
19 
{
20 
	Iobuf *p, *h, **l, **f;
21 
 
22 
	l = &hiob[addr%HIOB];
23 
	for(p = *l; p; p = p->hash) {
24 
		if(p->addr == addr && p->dev == dev) {
25 
			p->busy++;
26 
			return p;
27 
		}
28 
	}
29 
	/* Find a non-busy buffer from the tail */
30 
	for(p = iotail; p && (p->busy > 0); p = p->prev)
31 
		;
32 
	if(!p)
33 
		panic("all buffers busy");
34 
	if(p->dirty){
35 
		xwrite(p);
36 
		p->dirty = 0;
37 
	}
38 
 
39 
	if( xread(dev, p, addr) < 0)
40 
		return 0;
41 
	/* Delete from hash chain */
42 
	f = &hiob[p->addr%HIOB];
43 
	if( *f == p )
44 
		*f = p->hash;
45 
	else {
46 
		for(h = *f; h ; h = h->hash)
47 
			if( h->hash == p ){
48 
				h->hash = p->hash;
49 
				break;
50 
			}
51 
	}
52 
	/* Fill and hash */
53 
	p->hash = *l;
54 
	*l = p;
55 
	p->addr = addr;
56 
	p->dev = dev;
57 
	p->busy=1;
58 
 
59 
	return p;
60 
}
61 
void
62 
putbuf(Iobuf *p)
63 
{
64 
	if(p->busy <= 0)
65 
		panic("putbuf");
66 
	p->busy--;
67 
 
68 
	/* Link onto head for lru */
69 
	if(p == iohead)
70 
		return;
71 
	if( p == iotail ){
72 
		p->prev->next = 0;
73 
		iotail = p->prev;
74 
	}else{
75 
		p->prev->next = p->next;
76 
		p->next->prev = p->prev;
77 
	}
78 
 
79 
	p->prev = 0;
80 
	p->next = iohead;
81 
	iohead->prev = p;
82 
	iohead = p;
83 
}
84 
void
85 
dirtybuf(Iobuf *p)
86 
{
87 
	if(p->busy <=0)
88 
		panic("dirtybuf");
89 
	p->dirty = 1;
90 
}
91 
void
92 
syncbuf(void)
93 
{
94 
	Iobuf *p;
95 
 
96 
	for(p=&iobuf[0] ; p<&iobuf[NIOBUF]; p++)
97 
		if( p->dirty ){
98 
			xwrite(p);
99 
			p->dirty = 0;
100 
		}
101 
}
102 
void
103 
purgebuf(Xfs *dev)
104 
{
105 
	Iobuf *p;
106 
 
107 
	for(p=&iobuf[0]; p<&iobuf[NIOBUF]; p++)
108 
		if(p->dev == dev)
109 
			p->busy = 0;
110 
 
111 
	/* Blow hash chains */
112 
	memset(hiob, 0, sizeof(hiob));
113 
}
114 
void
115 
iobuf_init(void)
116 
{
117 
	Iobuf *p;
118 
 
119 
	iohead = iobuf;
120 
	iotail = iobuf+NIOBUF-1;
121 
 
122 
	for(p = iobuf; p <= iotail; p++) {
123 
		p->next = p+1;
124 
		p->prev = p-1;
125 
 
126 
		p->iobuf = (char *)malloc(EXT2_MAX_BLOCK_SIZE);
127 
		if(p->iobuf == 0)
128 
			panic("iobuf_init");
129 
	}
130 
 
131 
	iohead->prev = 0;
132 
	iotail->next = 0;
133 
}
134 
int
135 
xread(Xfs *dev, Iobuf *p, long addr)
136 
{
137 
	/*chat("xread %d,%d...", dev->dev, addr);*/
138 
 
139 
	seek(dev->dev, (vlong)addr*dev->block_size, 0);
140 
	if(read(dev->dev, p->iobuf, dev->block_size) != dev->block_size){
141 
		chat("xread %d, block=%d failed ...", dev->dev, addr);
142 
		errno = Eio;
143 
		return -1;
144 
	}
145 
	/*chat("xread ok...");*/
146 
	return 0;
147 
}
148 
void
149 
xwrite(Iobuf *p)
150 
{
151 
	Xfs *dev;
152 
	long addr;
153 
 
154 
	dev = p->dev;
155 
	addr = p->addr;
156 
	/*chat("xwrite %d,%d...", dev->dev, addr);*/
157 
 
158 
	seek(dev->dev, (vlong)addr*dev->block_size, 0);
159 
	if(write(dev->dev, p->iobuf, dev->block_size) != dev->block_size){
160 
		chat("xwrite %d, block=%d failed ...", dev->dev, addr);
161 
		errno = Eio;
162 
		return;
163 
	}
164 
	/*chat("xwrite ok...");*/
165 
}
166 
void
167 
dumpbuf(void)
168 
{
169 
	Iobuf *p;
170 
 
171 
	for(p = iotail; p ; p = p->prev)
172 
		if( p->busy )
173 
			mchat("\nHi ERROR buf(%x, %d, %d)\n", p, p->addr, p->busy);
174 
}