xref: /freebsd/sys/geom/geom_slice.c (revision f9218d3d4fd34f082473b3a021c6d4d109fb47cf)
1 /*-
2  * Copyright (c) 2002 Poul-Henning Kamp
3  * Copyright (c) 2002 Networks Associates Technology, Inc.
4  * All rights reserved.
5  *
6  * This software was developed for the FreeBSD Project by Poul-Henning Kamp
7  * and NAI Labs, the Security Research Division of Network Associates, Inc.
8  * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
9  * DARPA CHATS research program.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. The names of the authors may not be used to endorse or promote
20  *    products derived from this software without specific prior written
21  *    permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  * $FreeBSD$
36  */
37 
38 
39 #include <sys/param.h>
40 #include <sys/stdint.h>
41 #ifndef _KERNEL
42 #include <stdio.h>
43 #include <unistd.h>
44 #include <stdlib.h>
45 #include <signal.h>
46 #include <string.h>
47 #include <err.h>
48 #else
49 #include <sys/systm.h>
50 #include <sys/kernel.h>
51 #include <sys/malloc.h>
52 #include <sys/bio.h>
53 #include <sys/sysctl.h>
54 #include <sys/proc.h>
55 #include <sys/kthread.h>
56 #include <sys/lock.h>
57 #include <sys/mutex.h>
58 #endif
59 #include <sys/errno.h>
60 #include <sys/sbuf.h>
61 #include <geom/geom.h>
62 #include <geom/geom_slice.h>
63 #include <machine/stdarg.h>
64 
65 static g_orphan_t g_slice_orphan;
66 static g_access_t g_slice_access;
67 static g_start_t g_slice_start;
68 
69 static struct g_slicer *
70 g_slice_init(unsigned nslice, unsigned scsize)
71 {
72 	struct g_slicer *gsp;
73 
74 	gsp = g_malloc(sizeof *gsp, M_WAITOK | M_ZERO);
75 	gsp->softc = g_malloc(scsize, M_WAITOK | M_ZERO);
76 	gsp->slices = g_malloc(nslice * sizeof(struct g_slice),
77 	    M_WAITOK | M_ZERO);
78 	gsp->nslice = nslice;
79 	return (gsp);
80 }
81 
82 static int
83 g_slice_access(struct g_provider *pp, int dr, int dw, int de)
84 {
85 	int error;
86 	u_int u;
87 	struct g_geom *gp;
88 	struct g_consumer *cp;
89 	struct g_provider *pp2;
90 	struct g_slicer *gsp;
91 	struct g_slice *gsl, *gsl2;
92 
93 	gp = pp->geom;
94 	cp = LIST_FIRST(&gp->consumer);
95 	KASSERT (cp != NULL, ("g_slice_access but no consumer"));
96 	gsp = gp->softc;
97 	gsl = &gsp->slices[pp->index];
98 	for (u = 0; u < gsp->nslice; u++) {
99 		gsl2 = &gsp->slices[u];
100 		if (gsl2->length == 0)
101 			continue;
102 		if (u == pp->index)
103 			continue;
104 		if (gsl->offset + gsl->length <= gsl2->offset)
105 			continue;
106 		if (gsl2->offset + gsl2->length <= gsl->offset)
107 			continue;
108 		/* overlap */
109 		pp2 = gsl2->provider;
110 		if ((pp->acw + dw) > 0 && pp2->ace > 0)
111 			return (EPERM);
112 		if ((pp->ace + de) > 0 && pp2->acw > 0)
113 			return (EPERM);
114 	}
115 	/* On first open, grab an extra "exclusive" bit */
116 	if (cp->acr == 0 && cp->acw == 0 && cp->ace == 0)
117 		de++;
118 	/* ... and let go of it on last close */
119 	if ((cp->acr + dr) == 0 && (cp->acw + dw) == 0 && (cp->ace + de) == 1)
120 		de--;
121 	error = g_access_rel(cp, dr, dw, de);
122 	return (error);
123 }
124 
125 void
126 g_slice_finish_hot(struct bio *bp)
127 {
128 	struct bio *bp2;
129 	struct g_geom *gp;
130 	struct g_consumer *cp;
131 	struct g_slicer *gsp;
132 	struct g_slice *gsl;
133 	int idx;
134 
135 	KASSERT(bp->bio_to != NULL, ("NULL bio_to in g_slice_finish_hot(%p)", bp));
136 	KASSERT(bp->bio_from != NULL, ("NULL bio_from in g_slice_finish_hot(%p)", bp));
137 	gp = bp->bio_to->geom;
138 	gsp = gp->softc;
139 	cp = LIST_FIRST(&gp->consumer);
140 	KASSERT(cp != NULL, ("NULL consumer in g_slice_finish_hot(%p)", bp));
141 	idx = bp->bio_to->index;
142 	gsl = &gsp->slices[idx];
143 
144 	bp2 = g_clone_bio(bp);
145 	if (bp2 == NULL) {
146 		g_io_deliver(bp, ENOMEM);
147 		return;
148 	}
149 	if (bp2->bio_offset + bp2->bio_length > gsl->length)
150 		bp2->bio_length = gsl->length - bp2->bio_offset;
151 	bp2->bio_done = g_std_done;
152 	bp2->bio_offset += gsl->offset;
153 	g_io_request(bp2, cp);
154 	return;
155 }
156 
157 static void
158 g_slice_start(struct bio *bp)
159 {
160 	struct bio *bp2;
161 	struct g_provider *pp;
162 	struct g_geom *gp;
163 	struct g_consumer *cp;
164 	struct g_slicer *gsp;
165 	struct g_slice *gsl, *gmp;
166 	int idx, error;
167 	u_int m_index;
168 	off_t t;
169 
170 	pp = bp->bio_to;
171 	gp = pp->geom;
172 	gsp = gp->softc;
173 	cp = LIST_FIRST(&gp->consumer);
174 	idx = pp->index;
175 	gsl = &gsp->slices[idx];
176 	switch(bp->bio_cmd) {
177 	case BIO_READ:
178 	case BIO_WRITE:
179 	case BIO_DELETE:
180 		if (bp->bio_offset > gsl->length) {
181 			g_io_deliver(bp, EINVAL); /* XXX: EWHAT ? */
182 			return;
183 		}
184 		/*
185 		 * Check if we collide with any hot spaces, and call the
186 		 * method once if so.
187 		 */
188 		t = bp->bio_offset + gsl->offset;
189 		/* .ctl devices may take us negative */
190 		if (t < 0 || (t + bp->bio_length) < 0) {
191 			g_io_deliver(bp, EINVAL);
192 			return;
193 		}
194 		for (m_index = 0; m_index < gsp->nhot; m_index++) {
195 			gmp = &gsp->hot[m_index];
196 			if (t >= gmp->offset + gmp->length)
197 				continue;
198 			if (t + bp->bio_length <= gmp->offset)
199 				continue;
200 			error = gsp->start(bp);
201 			if (error == EJUSTRETURN)
202 				return;
203 			else if (error) {
204 				g_io_deliver(bp, error);
205 				return;
206 			}
207 			break;
208 		}
209 		bp2 = g_clone_bio(bp);
210 		if (bp2 == NULL) {
211 			g_io_deliver(bp, ENOMEM);
212 			return;
213 		}
214 		if (bp2->bio_offset + bp2->bio_length > gsl->length)
215 			bp2->bio_length = gsl->length - bp2->bio_offset;
216 		bp2->bio_done = g_std_done;
217 		bp2->bio_offset += gsl->offset;
218 		g_io_request(bp2, cp);
219 		return;
220 	case BIO_GETATTR:
221 	case BIO_SETATTR:
222 		/* Give the real method a chance to override */
223 		if (gsp->start(bp))
224 			return;
225 		if (!strcmp("GEOM::frontstuff", bp->bio_attribute)) {
226 			t = gsp->cfrontstuff;
227 			if (gsp->frontstuff > t)
228 				t = gsp->frontstuff;
229 			t -= gsl->offset;
230 			if (t < 0)
231 				t = 0;
232 			if (t > gsl->length)
233 				t = gsl->length;
234 			g_handleattr_off_t(bp, "GEOM::frontstuff", t);
235 			return;
236 		}
237 #ifdef _KERNEL
238 		if (!strcmp("GEOM::kerneldump", bp->bio_attribute)) {
239 			struct g_kerneldump *gkd;
240 
241 			gkd = (struct g_kerneldump *)bp->bio_data;
242 			gkd->offset += gsp->slices[idx].offset;
243 			if (gkd->length > gsp->slices[idx].length)
244 				gkd->length = gsp->slices[idx].length;
245 			/* now, pass it on downwards... */
246 		}
247 #endif
248 		bp2 = g_clone_bio(bp);
249 		if (bp2 == NULL) {
250 			g_io_deliver(bp, ENOMEM);
251 			return;
252 		}
253 		bp2->bio_done = g_std_done;
254 		g_io_request(bp2, cp);
255 		break;
256 	default:
257 		g_io_deliver(bp, EOPNOTSUPP);
258 		return;
259 	}
260 }
261 
262 void
263 g_slice_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp)
264 {
265 	struct g_slicer *gsp;
266 
267 	gsp = gp->softc;
268 	if (indent == NULL) {
269 		sbuf_printf(sb, " i %u", pp->index);
270 		sbuf_printf(sb, " o %ju",
271 		    (uintmax_t)gsp->slices[pp->index].offset);
272 		return;
273 	}
274 	if (gp != NULL && (pp == NULL && cp == NULL)) {
275 		sbuf_printf(sb, "%s<frontstuff>%ju</frontstuff>\n",
276 		    indent, (intmax_t)gsp->frontstuff);
277 	}
278 	if (pp != NULL) {
279 		sbuf_printf(sb, "%s<index>%u</index>\n", indent, pp->index);
280 		sbuf_printf(sb, "%s<length>%ju</length>\n",
281 		    indent, (uintmax_t)gsp->slices[pp->index].length);
282 		sbuf_printf(sb, "%s<seclength>%ju</seclength>\n", indent,
283 		    (uintmax_t)gsp->slices[pp->index].length / 512);
284 		sbuf_printf(sb, "%s<offset>%ju</offset>\n", indent,
285 		    (uintmax_t)gsp->slices[pp->index].offset);
286 		sbuf_printf(sb, "%s<secoffset>%ju</secoffset>\n", indent,
287 		    (uintmax_t)gsp->slices[pp->index].offset / 512);
288 	}
289 }
290 
291 int
292 g_slice_config(struct g_geom *gp, u_int idx, int how, off_t offset, off_t length, u_int sectorsize, const char *fmt, ...)
293 {
294 	struct g_provider *pp, *pp2;
295 	struct g_slicer *gsp;
296 	struct g_slice *gsl;
297 	va_list ap;
298 	struct sbuf *sb;
299 	int error, acc;
300 
301 	g_trace(G_T_TOPOLOGY, "g_slice_config(%s, %d, %d)",
302 	     gp->name, idx, how);
303 	g_topology_assert();
304 	gsp = gp->softc;
305 	error = 0;
306 	if (idx >= gsp->nslice)
307 		return(EINVAL);
308 	gsl = &gsp->slices[idx];
309 	pp = gsl->provider;
310 	if (pp != NULL)
311 		acc = pp->acr + pp->acw + pp->ace;
312 	else
313 		acc = 0;
314 	if (acc != 0 && how != G_SLICE_CONFIG_FORCE) {
315 		if (length < gsl->length)
316 			return(EBUSY);
317 		if (offset != gsl->offset)
318 			return(EBUSY);
319 	}
320 	/* XXX: check offset + length <= MEDIASIZE */
321 	if (how == G_SLICE_CONFIG_CHECK)
322 		return (0);
323 	gsl->length = length;
324 	gsl->offset = offset;
325 	gsl->sectorsize = sectorsize;
326 	if (length == 0) {
327 		if (pp == NULL)
328 			return (0);
329 		if (bootverbose)
330 			printf("GEOM: Deconfigure %s\n", pp->name);
331 		g_orphan_provider(pp, ENXIO);
332 		gsl->provider = NULL;
333 		gsp->nprovider--;
334 		return (0);
335 	}
336 	if (pp != NULL) {
337 		if (bootverbose)
338 			printf("GEOM: Reconfigure %s, start %jd length %jd end %jd\n",
339 			    pp->name, (intmax_t)offset, (intmax_t)length,
340 			    (intmax_t)(offset + length - 1));
341 		pp->mediasize = gsl->length;
342 		return (0);
343 	}
344 	va_start(ap, fmt);
345 	sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND);
346 	sbuf_vprintf(sb, fmt, ap);
347 	sbuf_finish(sb);
348 	pp = g_new_providerf(gp, sbuf_data(sb));
349 	pp2 = LIST_FIRST(&gp->consumer)->provider;
350 	pp->flags = pp2->flags & G_PF_CANDELETE;
351 	if (pp2->stripesize > 0) {
352 		pp->stripesize = pp2->stripesize;
353 		pp->stripeoffset = (pp2->stripeoffset + offset) % pp->stripesize;
354 	}
355 	if (bootverbose)
356 		printf("GEOM: Configure %s, start %jd length %jd end %jd\n",
357 		    pp->name, (intmax_t)offset, (intmax_t)length,
358 		    (intmax_t)(offset + length - 1));
359 	pp->index = idx;
360 	pp->mediasize = gsl->length;
361 	pp->sectorsize = gsl->sectorsize;
362 	gsl->provider = pp;
363 	gsp->nprovider++;
364 	g_error_provider(pp, 0);
365 	sbuf_delete(sb);
366 	return(0);
367 }
368 
369 int
370 g_slice_conf_hot(struct g_geom *gp, u_int idx, off_t offset, off_t length)
371 {
372 	struct g_slicer *gsp;
373 	struct g_slice *gsl, *gsl2;
374 
375 	g_trace(G_T_TOPOLOGY, "g_slice_conf_hot()");
376 	g_topology_assert();
377 	gsp = gp->softc;
378 	gsl = gsp->hot;
379 	if(idx >= gsp->nhot) {
380 		gsl2 = g_malloc((idx + 1) * sizeof *gsl2, M_WAITOK | M_ZERO);
381 		if (gsp->hot != NULL)
382 			bcopy(gsp->hot, gsl2, gsp->nhot * sizeof *gsl2);
383 		gsp->hot = gsl2;
384 		if (gsp->hot != NULL)
385 			g_free(gsl);
386 		gsl = gsl2;
387 		gsp->nhot = idx + 1;
388 	}
389 	if (bootverbose)
390 		printf("GEOM: Add %s hot[%d] start %jd length %jd end %jd\n",
391 		    gp->name, idx, (intmax_t)offset, (intmax_t)length,
392 		    (intmax_t)(offset + length - 1));
393 	gsl[idx].offset = offset;
394 	gsl[idx].length = length;
395 	return (0);
396 }
397 
398 struct g_geom *
399 g_slice_new(struct g_class *mp, u_int slices, struct g_provider *pp, struct g_consumer **cpp, void *extrap, int extra, g_slice_start_t *start)
400 {
401 	struct g_geom *gp;
402 	struct g_slicer *gsp;
403 	struct g_consumer *cp;
404 	void **vp;
405 	int error, i;
406 
407 	g_topology_assert();
408 	vp = (void **)extrap;
409 	gp = g_new_geomf(mp, "%s", pp->name);
410 	gsp = g_slice_init(slices, extra);
411 	gsp->start = start;
412 	gp->access = g_slice_access;
413 	gp->orphan = g_slice_orphan;
414 	gp->softc = gsp;
415 	gp->start = g_slice_start;
416 	gp->spoiled = g_std_spoiled;
417 	gp->dumpconf = g_slice_dumpconf;
418 	cp = g_new_consumer(gp);
419 	error = g_attach(cp, pp);
420 	if (error == 0)
421 		error = g_access_rel(cp, 1, 0, 0);
422 	if (error) {
423 		if (cp->provider != NULL)
424 			g_detach(cp);
425 		g_destroy_consumer(cp);
426 		g_free(gsp->slices);
427 		g_free(gp->softc);
428 		g_destroy_geom(gp);
429 		return (NULL);
430 	}
431 	/* Find out if there are any magic bytes on the consumer */
432 	i = sizeof gsp->cfrontstuff;
433 	error = g_io_getattr("GEOM::frontstuff", cp, &i, &gsp->cfrontstuff);
434 	if (error)
435 		gsp->cfrontstuff = 0;
436 	*vp = gsp->softc;
437 	*cpp = cp;
438 	return (gp);
439 }
440 
441 static void
442 g_slice_orphan(struct g_consumer *cp)
443 {
444 	struct g_geom *gp;
445 	struct g_provider *pp;
446 	int error;
447 
448 	g_trace(G_T_TOPOLOGY, "g_slice_orphan(%p/%s)", cp, cp->provider->name);
449 	g_topology_assert();
450 	KASSERT(cp->provider->error != 0,
451 	    ("g_slice_orphan with error == 0"));
452 
453 	gp = cp->geom;
454 	/* XXX: Not good enough we leak the softc and its suballocations */
455 	gp->flags |= G_GEOM_WITHER;
456 	error = cp->provider->error;
457 	LIST_FOREACH(pp, &gp->provider, provider)
458 		g_orphan_provider(pp, error);
459 	return;
460 }
461