xref: /plan9/sys/src/cmd/cwfs/wren.c (revision 390ad7e13cfcfef6cf0377dab79d2a0ed3c8f713)
1 /*
2  * drive disks
3  * used to be just scsi disks, and issued scsi commands directly to the host
4  * adapter, but now it just does normal i/o.
5  */
6 #include "all.h"
7 
8 enum { Sectorsz = 512, };		/* usual disk sector size */
9 
10 typedef	struct	Wren	Wren;
11 struct	Wren
12 {
13 	long	block;			/* size of a block -- from config */
14 	Devsize	nblock;			/* number of blocks -- from config */
15 	long	mult;			/* multiplier to get physical blocks */
16 	Devsize	max;			/* number of logical blocks */
17 
18 //	char	*sddir;			/* /dev/sdXX name */
19 };
20 
21 char *
dataof(char * file)22 dataof(char *file)
23 {
24 	char *datanm;
25 	Dir *dir;
26 
27 	dir = dirstat(file);
28 	if (dir != nil && dir->mode & DMDIR)
29 		datanm = smprint("%s/data", file);
30 	else
31 		datanm = strdup(file);
32 	free(dir);
33 	return datanm;
34 }
35 
36 void
wreninit(Device * d)37 wreninit(Device *d)
38 {
39 	Wren *dr;
40 	Dir *dir;
41 
42 	if(d->private)
43 		return;
44 	d->private = dr = malloc(sizeof(Wren));
45 
46 	if (d->wren.file)
47 		d->wren.sddata = dataof(d->wren.file);
48 	else {
49 		d->wren.sddir = sdof(d);
50 		d->wren.sddata = smprint("%s/data", d->wren.sddir);
51 	}
52 
53 	assert(d->wren.fd <= 0);
54 	d->wren.fd = open(d->wren.sddata, ORDWR);
55 	if (d->wren.fd < 0)
56 		panic("wreninit: can't open %s for %Z: %r", d->wren.sddata, d);
57 
58 	dr->block = inqsize(d->wren.sddata);
59 	if(dr->block <= 0 || dr->block >= 16*1024) {
60 		print("\twreninit %Z block size %ld, setting to %d\n",
61 			d, dr->block, Sectorsz);
62 		dr->block = Sectorsz;
63 	}
64 
65 	dir = dirfstat(d->wren.fd);
66 	dr->nblock = dir->length / dr->block;
67 	free(dir);
68 
69 	dr->mult = (RBUFSIZE + dr->block - 1) / dr->block;
70 	dr->max = (dr->nblock + 1) / dr->mult;
71 	print("\tdisk drive %Z: %,lld %ld-byte sectors, ",
72 		d, (Wideoff)dr->nblock, dr->block);
73 	print("%,lld %d-byte blocks\n", (Wideoff)dr->max, RBUFSIZE);
74 	print("\t\t%ld multiplier\n", dr->mult);
75 }
76 
77 Devsize
wrensize(Device * d)78 wrensize(Device *d)
79 {
80 	return ((Wren *)d->private)->max;
81 }
82 
83 int
wrenread(Device * d,Off b,void * c)84 wrenread(Device *d, Off b, void *c)
85 {
86 	int r = 0;
87 	Wren *dr = d->private;
88 
89 	if (dr == nil)
90 		panic("wrenread: no drive (%Z) block %lld", d, (Wideoff)b);
91 	if(b >= dr->max) {
92 		print("wrenread: block out of range %Z(%lld)\n", d, (Wideoff)b);
93 		r = 0x040;
94 	} else if (pread(d->wren.fd, c, RBUFSIZE, (vlong)b*RBUFSIZE) != RBUFSIZE) {
95 		print("wrenread: error on %Z(%lld): %r\n", d, (Wideoff)b);
96 		cons.nwrenre++;
97 		r = 1;
98 	}
99 	return r;
100 }
101 
102 int
wrenwrite(Device * d,Off b,void * c)103 wrenwrite(Device *d, Off b, void *c)
104 {
105 	int r = 0;
106 	Wren *dr = d->private;
107 
108 	if (dr == nil)
109 		panic("wrenwrite: no drive (%Z) block %lld", d, (Wideoff)b);
110 	if(b >= dr->max) {
111 		print("wrenwrite: block out of range %Z(%lld)\n",
112 			d, (Wideoff)b);
113 		r = 0x040;
114 	} else if (pwrite(d->wren.fd, c, RBUFSIZE, (vlong)b*RBUFSIZE) != RBUFSIZE) {
115 		print("wrenwrite: error on %Z(%lld): %r\n", d, (Wideoff)b);
116 		cons.nwrenwe++;
117 		r = 1;
118 	}
119 	return r;
120 }
121