subr_disk.c revision 51822 
1/*
2 * ----------------------------------------------------------------------------
3 * "THE BEER-WARE LICENSE" (Revision 42):
4 * <phk@FreeBSD.ORG> wrote this file.  As long as you retain this notice you
5 * can do whatever you want with this stuff. If we meet some day, and you think
6 * this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp
7 * ----------------------------------------------------------------------------
8 *
9 * $FreeBSD: head/sys/kern/subr_disk.c 51822 1999-09-30 19:03:25Z phk $
10 *
11 */
12
13#include <sys/param.h>
14#include <sys/systm.h>
15#include <sys/kernel.h>
16#include <sys/sysctl.h>
17#include <sys/buf.h>
18#include <sys/conf.h>
19#include <sys/disk.h>
20#include <sys/malloc.h>
21#include <sys/vnode.h>
22#include <machine/md_var.h>
23
24MALLOC_DEFINE(M_DISK, "disk", "disk data");
25
26static d_strategy_t diskstrategy;
27static d_open_t diskopen;
28static d_close_t diskclose;
29static d_ioctl_t diskioctl;
30static d_psize_t diskpsize;
31
32dev_t
33disk_create(int unit, struct disk *dp, int flags, struct cdevsw *cdevsw, struct cdevsw *proto)
34{
35	dev_t dev;
36
37	bzero(dp, sizeof(*dp));
38
39	dev = makedev(cdevsw->d_maj, 0);
40	if (!devsw(dev)) {
41		*proto = *cdevsw;
42		proto->d_open = diskopen;
43		proto->d_close = diskclose;
44		proto->d_ioctl = diskioctl;
45		proto->d_strategy = diskstrategy;
46		proto->d_psize = diskpsize;
47		cdevsw_add(proto);
48	}
49
50	printf("Creating DISK %s%d\n", cdevsw->d_name, unit);
51	dev = make_dev(proto, dkmakeminor(unit, WHOLE_DISK_SLICE, RAW_PART),
52	    0, 0, 0, "r%s%d", cdevsw->d_name, unit);
53
54	dev->si_disk = dp;
55	dp->d_dev = dev;
56	dp->d_flags = flags;
57	dp->d_devsw = cdevsw;
58	return (dev);
59}
60
61int
62disk_dumpcheck(dev_t dev, u_int *count, u_int *blkno, u_int *secsize)
63{
64	struct disk *dp;
65	struct disklabel *dl;
66	u_int boff;
67
68	dp = dev->si_disk;
69	if (!dp)
70		return (ENXIO);
71	if (!dp->d_slice)
72		return (ENXIO);
73	dl = dsgetlabel(dev, dp->d_slice);
74	if (!dl)
75		return (ENXIO);
76	*count = (u_long)Maxmem * PAGE_SIZE / dl->d_secsize;
77	if (dumplo < 0 ||
78	    (dumplo + *count > dl->d_partitions[dkpart(dev)].p_size))
79		return (EINVAL);
80	boff = dl->d_partitions[dkpart(dev)].p_offset +
81	    dp->d_slice->dss_slices[dkslice(dev)].ds_offset;
82	*blkno = boff + dumplo;
83	*secsize = dl->d_secsize;
84	return (0);
85
86}
87
88void
89disk_invalidate (struct disk *disk)
90{
91	dsgone(&disk->d_slice);
92}
93
94void
95disk_delete(dev_t dev)
96{
97	return;
98}
99
100/*
101 * The cdevsw functions
102 */
103
104static int
105diskopen(dev_t dev, int oflags, int devtype, struct proc *p)
106{
107	dev_t pdev;
108	struct disk *dp;
109	int error;
110
111	error = 0;
112	pdev = dkmodpart(dkmodslice(dev, WHOLE_DISK_SLICE), RAW_PART);
113
114	dp = pdev->si_disk;
115	if (!dp)
116		return (ENXIO);
117
118	dev->si_disk = dp;
119	dev->si_drv1 = pdev->si_drv1;
120	dev->si_drv2 = pdev->si_drv2;
121
122	if (!dsisopen(dp->d_slice))
123		error = dp->d_devsw->d_open(dev, oflags, devtype, p);
124
125	if (error)
126		return(error);
127
128	error = dsopen(dev, devtype, dp->d_flags, &dp->d_slice, &dp->d_label);
129
130	if (!dsisopen(dp->d_slice))
131		dp->d_devsw->d_close(dev, oflags, devtype, p);
132
133	return(error);
134}
135
136static int
137diskclose(dev_t dev, int fflag, int devtype, struct proc *p)
138{
139	struct disk *dp;
140	int error;
141
142	error = 0;
143	dp = dev->si_disk;
144	dsclose(dev, devtype, dp->d_slice);
145	if (!dsisopen(dp->d_slice))
146		error = dp->d_devsw->d_close(dev, fflag, devtype, p);
147	return (error);
148}
149
150static void
151diskstrategy(struct buf *bp)
152{
153	dev_t pdev;
154	struct disk *dp;
155
156	dp = bp->b_dev->si_disk;
157	if (!dp) {
158		pdev = dkmodpart(dkmodslice(bp->b_dev, WHOLE_DISK_SLICE), RAW_PART);
159		dp = pdev->si_disk;
160		bp->b_dev->si_drv1 = pdev->si_drv1;
161		bp->b_dev->si_drv2 = pdev->si_drv2;
162		/* XXX: don't set bp->b_dev->si_disk (?) */
163	} else {
164		pdev = dp->d_dev;
165	}
166
167	if (!dp) {
168		bp->b_error = ENXIO;
169		bp->b_flags |= B_ERROR;
170		biodone(bp);
171		return;
172	}
173
174	if (dscheck(bp, dp->d_slice) < 0) {
175		biodone(bp);
176		return;
177	}
178
179	dp->d_devsw->d_strategy(bp);
180	return;
181
182}
183
184static int
185diskioctl(dev_t dev, u_long cmd, caddr_t data, int fflag, struct proc *p)
186{
187	struct disk *dp;
188	int error;
189
190	dp = dev->si_disk;
191	error = dsioctl(dev, cmd, data, fflag, &dp->d_slice);
192	if (error == ENOIOCTL)
193		error = dp->d_devsw->d_ioctl(dev, cmd, data, fflag, p);
194	return (error);
195}
196
197static int
198diskpsize(dev_t dev)
199{
200	struct disk *dp;
201	dev_t pdev;
202
203	dp = dev->si_disk;
204	if (!dp) {
205		pdev = dkmodpart(dkmodslice(dev, WHOLE_DISK_SLICE), RAW_PART);
206		dp = pdev->si_disk;
207		dev->si_drv1 = pdev->si_drv1;
208		dev->si_drv2 = pdev->si_drv2;
209		/* XXX: don't set bp->b_dev->si_disk (?) */
210	}
211	return (dssize(dev, &dp->d_slice));
212}
213
214SYSCTL_DECL(_debug_sizeof);
215
216SYSCTL_INT(_debug_sizeof, OID_AUTO, disklabel, CTLFLAG_RD,
217    0, sizeof(struct disklabel), "sizeof(struct disklabel)");
218
219SYSCTL_INT(_debug_sizeof, OID_AUTO, diskslices, CTLFLAG_RD,
220    0, sizeof(struct diskslices), "sizeof(struct diskslices)");
221
222SYSCTL_INT(_debug_sizeof, OID_AUTO, disk, CTLFLAG_RD,
223    0, sizeof(struct disk), "sizeof(struct disk)");
224