xref: /dragonfly/sys/kern/subr_disk.c (revision 1d1731fa)
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: src/sys/kern/subr_disk.c,v 1.20.2.6 2001/10/05 07:14:57 peter Exp $
10  * $DragonFly: src/sys/kern/subr_disk.c,v 1.5 2003/07/22 17:03:33 dillon Exp $
11  *
12  */
13 
14 #include <sys/param.h>
15 #include <sys/systm.h>
16 #include <sys/kernel.h>
17 #include <sys/sysctl.h>
18 #include <sys/buf.h>
19 #include <sys/conf.h>
20 #include <sys/disk.h>
21 #include <sys/malloc.h>
22 #include <sys/sysctl.h>
23 #include <machine/md_var.h>
24 #include <sys/ctype.h>
25 #include <sys/msgport.h>
26 #include <sys/msgport2.h>
27 
28 static MALLOC_DEFINE(M_DISK, "disk", "disk data");
29 
30 static d_strategy_t diskstrategy;
31 static d_open_t diskopen;
32 static d_close_t diskclose;
33 static d_ioctl_t diskioctl;
34 static d_psize_t diskpsize;
35 static int disk_putport(lwkt_port_t port, lwkt_msg_t msg);
36 
37 static LIST_HEAD(, disk) disklist = LIST_HEAD_INITIALIZER(&disklist);
38 
39 static void
40 inherit_raw(dev_t pdev, dev_t dev)
41 {
42 	dev->si_disk = pdev->si_disk;
43 	dev->si_drv1 = pdev->si_drv1;
44 	dev->si_drv2 = pdev->si_drv2;
45 	dev->si_iosize_max = pdev->si_iosize_max;
46 	dev->si_bsize_phys = pdev->si_bsize_phys;
47 	dev->si_bsize_best = pdev->si_bsize_best;
48 }
49 
50 /*
51  * Create a slice and unit managed disk.  The underlying raw disk device
52  * is specified by cdevsw.  We create the device as a managed device by
53  * first creating it normally then overriding the message port with our
54  * own frontend (which will be responsible for assigning pblkno).
55  */
56 dev_t
57 disk_create(int unit, struct disk *dp, int flags, struct cdevsw *cdevsw)
58 {
59 	dev_t dev;
60 
61 	bzero(dp, sizeof(*dp));
62 	lwkt_init_port(&dp->d_port, NULL);	/* intercept port */
63 	dp->d_port.mp_beginmsg = disk_putport;
64 
65 	dev = makedev(cdevsw->d_maj, 0);	/* base device */
66 	dev->si_disk = dp;
67 						/* forwarding port */
68 	dp->d_fwdport = cdevsw_add_override(cdevsw, &dp->d_port);
69 
70 	if (bootverbose)
71 		printf("Creating DISK %s%d\n", cdevsw->d_name, unit);
72 
73   	/*
74 	 * The whole disk placemarker holds the disk structure.
75 	 */
76 	dev = make_dev(cdevsw, dkmakeminor(unit, WHOLE_DISK_SLICE, RAW_PART),
77 	    UID_ROOT, GID_OPERATOR, 0640, "%s%d", cdevsw->d_name, unit);
78 	dev->si_disk = dp;
79 	dp->d_dev = dev;
80 	dp->d_dsflags = flags;
81 	LIST_INSERT_HEAD(&disklist, dp, d_list);
82 	return (dev);
83 }
84 
85 void
86 disk_destroy(struct disk *disk)
87 {
88 	dev_t dev = disk->d_dev;
89 
90 	LIST_REMOVE(disk, d_list);
91 	bzero(disk, sizeof(*disk));
92 	dev->si_disk = NULL;
93 	destroy_dev(dev);
94 	/* YYY remove cdevsw entries? */
95 	return;
96 }
97 
98 int
99 disk_dumpcheck(dev_t dev, u_int *count, u_int *blkno, u_int *secsize)
100 {
101 	struct disk *dp;
102 	struct disklabel *dl;
103 	u_int boff;
104 
105 	dp = dev->si_disk;
106 	if (!dp)
107 		return (ENXIO);
108 	if (!dp->d_slice)
109 		return (ENXIO);
110 	dl = dsgetlabel(dev, dp->d_slice);
111 	if (!dl)
112 		return (ENXIO);
113 	*count = Maxmem * (PAGE_SIZE / dl->d_secsize);
114 	if (dumplo <= LABELSECTOR ||
115 	    (dumplo + *count > dl->d_partitions[dkpart(dev)].p_size))
116 		return (EINVAL);
117 	boff = dl->d_partitions[dkpart(dev)].p_offset +
118 	    dp->d_slice->dss_slices[dkslice(dev)].ds_offset;
119 	*blkno = boff + dumplo;
120 	*secsize = dl->d_secsize;
121 	return (0);
122 
123 }
124 
125 void
126 disk_invalidate (struct disk *disk)
127 {
128 	if (disk->d_slice)
129 		dsgone(&disk->d_slice);
130 }
131 
132 struct disk *
133 disk_enumerate(struct disk *disk)
134 {
135 	if (!disk)
136 		return (LIST_FIRST(&disklist));
137 	else
138 		return (LIST_NEXT(disk, d_list));
139 }
140 
141 static int
142 sysctl_disks(SYSCTL_HANDLER_ARGS)
143 {
144 	struct disk *disk;
145 	int error, first;
146 
147 	disk = NULL;
148 	first = 1;
149 
150 	while ((disk = disk_enumerate(disk))) {
151 		if (!first) {
152 			error = SYSCTL_OUT(req, " ", 1);
153 			if (error)
154 				return error;
155 		} else {
156 			first = 0;
157 		}
158 		error = SYSCTL_OUT(req, disk->d_dev->si_name, strlen(disk->d_dev->si_name));
159 		if (error)
160 			return error;
161 	}
162 	error = SYSCTL_OUT(req, "", 1);
163 	return error;
164 }
165 
166 SYSCTL_PROC(_kern, OID_AUTO, disks, CTLTYPE_STRING | CTLFLAG_RD, 0, NULL,
167     sysctl_disks, "A", "names of available disks");
168 
169 /*
170  * The port intercept functions
171  */
172 static
173 int
174 disk_putport(lwkt_port_t port, lwkt_msg_t lmsg)
175 {
176 	struct disk *disk = (struct disk *)port;
177 	cdevallmsg_t msg = (cdevallmsg_t)lmsg;
178 	int error;
179 
180 	switch(msg->am_lmsg.ms_cmd) {
181 	case CDEV_CMD_OPEN:
182 		error = diskopen(
183 			    msg->am_open.msg.dev,
184 			    msg->am_open.oflags,
185 			    msg->am_open.devtype,
186 			    msg->am_open.td);
187 		break;
188 	case CDEV_CMD_CLOSE:
189 		error = diskclose(
190 			    msg->am_close.msg.dev,
191 			    msg->am_close.fflag,
192 			    msg->am_close.devtype,
193 			    msg->am_close.td);
194 		break;
195 	case CDEV_CMD_IOCTL:
196 		error = diskioctl(
197 			    msg->am_ioctl.msg.dev,
198 			    msg->am_ioctl.cmd,
199 			    msg->am_ioctl.data,
200 			    msg->am_ioctl.fflag,
201 			    msg->am_ioctl.td);
202 		break;
203 	case CDEV_CMD_STRATEGY:
204 		diskstrategy(msg->am_strategy.bp);
205 		error = 0;
206 		break;
207 	case CDEV_CMD_PSIZE:
208 		msg->am_psize.result = diskpsize(msg->am_psize.msg.dev);
209 		error = 0;      /* XXX */
210 		break;
211 	default:
212 		error = lwkt_forwardmsg(disk->d_fwdport, &msg->am_lmsg);
213 		break;
214 	}
215 	return(error);
216 }
217 
218 static int
219 diskopen(dev_t dev, int oflags, int devtype, struct thread *td)
220 {
221 	dev_t pdev;
222 	struct disk *dp;
223 	int error;
224 
225 	error = 0;
226 	pdev = dkmodpart(dkmodslice(dev, WHOLE_DISK_SLICE), RAW_PART);
227 
228 	dp = pdev->si_disk;
229 	if (dp == NULL)
230 		return (ENXIO);
231 
232 	while (dp->d_flags & DISKFLAG_LOCK) {
233 		dp->d_flags |= DISKFLAG_WANTED;
234 		error = tsleep(dp, PCATCH, "diskopen", hz);
235 		if (error)
236 			return (error);
237 	}
238 	dp->d_flags |= DISKFLAG_LOCK;
239 
240 	if (!dsisopen(dp->d_slice)) {
241 		if (!pdev->si_iosize_max)
242 			pdev->si_iosize_max = dev->si_iosize_max;
243 		error = dev_port_dopen(dp->d_fwdport, pdev, oflags, devtype, td);
244 	}
245 
246 	/* Inherit properties from the whole/raw dev_t */
247 	inherit_raw(pdev, dev);
248 
249 	if (error)
250 		goto out;
251 
252 	error = dsopen(dev, devtype, dp->d_dsflags, &dp->d_slice, &dp->d_label);
253 
254 	if (!dsisopen(dp->d_slice))
255 		dev_port_dclose(dp->d_fwdport, pdev, oflags, devtype, td);
256 out:
257 	dp->d_flags &= ~DISKFLAG_LOCK;
258 	if (dp->d_flags & DISKFLAG_WANTED) {
259 		dp->d_flags &= ~DISKFLAG_WANTED;
260 		wakeup(dp);
261 	}
262 
263 	return(error);
264 }
265 
266 static int
267 diskclose(dev_t dev, int fflag, int devtype, struct thread *td)
268 {
269 	struct disk *dp;
270 	int error;
271 	dev_t pdev;
272 
273 	error = 0;
274 	pdev = dkmodpart(dkmodslice(dev, WHOLE_DISK_SLICE), RAW_PART);
275 	dp = pdev->si_disk;
276 	if (!dp)
277 		return (ENXIO);
278 	dsclose(dev, devtype, dp->d_slice);
279 	if (!dsisopen(dp->d_slice))
280 		error = dev_port_dclose(dp->d_fwdport, pdev, fflag, devtype, td);
281 	return (error);
282 }
283 
284 static void
285 diskstrategy(struct buf *bp)
286 {
287 	dev_t pdev;
288 	struct disk *dp;
289 
290 	pdev = dkmodpart(dkmodslice(bp->b_dev, WHOLE_DISK_SLICE), RAW_PART);
291 	dp = pdev->si_disk;
292 	if (dp != bp->b_dev->si_disk)
293 		inherit_raw(pdev, bp->b_dev);
294 
295 	if (!dp) {
296 		bp->b_error = ENXIO;
297 		bp->b_flags |= B_ERROR;
298 		biodone(bp);
299 		return;
300 	}
301 
302 	if (dscheck(bp, dp->d_slice) <= 0) {
303 		biodone(bp);
304 		return;
305 	}
306 	dev_port_dstrategy(dp->d_fwdport, dp->d_dev, bp);
307 }
308 
309 /*
310  * note: when forwarding the ioctl we use the original device rather then
311  * the whole disk slice.
312  */
313 static int
314 diskioctl(dev_t dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
315 {
316 	struct disk *dp;
317 	int error;
318 	dev_t pdev;
319 
320 	pdev = dkmodpart(dkmodslice(dev, WHOLE_DISK_SLICE), RAW_PART);
321 	dp = pdev->si_disk;
322 	if (!dp)
323 		return (ENXIO);
324 	error = dsioctl(dev, cmd, data, fflag, &dp->d_slice);
325 	if (error == ENOIOCTL)
326 		error = dev_port_dioctl(dp->d_fwdport, dev, cmd, data, fflag, td);
327 	return (error);
328 }
329 
330 static int
331 diskpsize(dev_t dev)
332 {
333 	struct disk *dp;
334 	dev_t pdev;
335 
336 	pdev = dkmodpart(dkmodslice(dev, WHOLE_DISK_SLICE), RAW_PART);
337 	dp = pdev->si_disk;
338 	if (!dp)
339 		return (-1);
340 	if (dp != dev->si_disk) {
341 		dev->si_drv1 = pdev->si_drv1;
342 		dev->si_drv2 = pdev->si_drv2;
343 		/* XXX: don't set bp->b_dev->si_disk (?) */
344 	}
345 	return (dssize(dev, &dp->d_slice));
346 }
347 
348 SYSCTL_DECL(_debug_sizeof);
349 
350 SYSCTL_INT(_debug_sizeof, OID_AUTO, disklabel, CTLFLAG_RD,
351     0, sizeof(struct disklabel), "sizeof(struct disklabel)");
352 
353 SYSCTL_INT(_debug_sizeof, OID_AUTO, diskslices, CTLFLAG_RD,
354     0, sizeof(struct diskslices), "sizeof(struct diskslices)");
355 
356 SYSCTL_INT(_debug_sizeof, OID_AUTO, disk, CTLFLAG_RD,
357     0, sizeof(struct disk), "sizeof(struct disk)");
358