xref: /freebsd/sys/dev/cfi/cfi_disk.c (revision 716fd348e01c5f2ba125f878a634a753436c2994)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2009 Sam Leffler, Errno Consulting
5  * Copyright (c) 2012-2013, SRI International
6  * All rights reserved.
7  *
8  * Portions of this software were developed by SRI International and the
9  * University of Cambridge Computer Laboratory under DARPA/AFRL contract
10  * (FA8750-10-C-0237) ("CTSRD"), as part of the DARPA CRASH research
11  * programme.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/bio.h>
40 #include <sys/bus.h>
41 #include <sys/conf.h>
42 #include <sys/kernel.h>
43 #include <sys/malloc.h>
44 #include <sys/lock.h>
45 #include <sys/mutex.h>
46 #include <sys/module.h>
47 #include <sys/rman.h>
48 #include <sys/sysctl.h>
49 #include <sys/taskqueue.h>
50 
51 #include <machine/bus.h>
52 
53 #include <dev/cfi/cfi_var.h>
54 
55 #include <geom/geom.h>
56 #include <geom/geom_disk.h>
57 
58 struct cfi_disk_softc {
59 	struct cfi_softc *parent;
60 	struct disk	*disk;
61 	int		flags;
62 #define	CFI_DISK_OPEN	0x0001
63 	struct bio_queue_head bioq;	/* bio queue */
64 	struct mtx	qlock;		/* bioq lock */
65 	struct taskqueue *tq;		/* private task queue for i/o request */
66 	struct task	iotask;		/* i/o processing */
67 };
68 
69 #define	CFI_DISK_SECSIZE	512
70 #define	CFI_DISK_MAXIOSIZE	65536
71 
72 static int cfi_disk_detach(device_t);
73 static int cfi_disk_open(struct disk *);
74 static int cfi_disk_close(struct disk *);
75 static void cfi_io_proc(void *, int);
76 static int cfi_disk_getattr(struct bio *);
77 static void cfi_disk_strategy(struct bio *);
78 static int cfi_disk_ioctl(struct disk *, u_long, void *, int, struct thread *);
79 
80 static int
81 cfi_disk_probe(device_t dev)
82 {
83 	return 0;
84 }
85 
86 static int
87 cfi_disk_attach(device_t dev)
88 {
89 	struct cfi_disk_softc *sc = device_get_softc(dev);
90 
91 	sc->parent = device_get_softc(device_get_parent(dev));
92 	/* validate interface width; assumed by other code */
93 	if (sc->parent->sc_width != 1 &&
94 	    sc->parent->sc_width != 2 &&
95 	    sc->parent->sc_width != 4)
96 		return EINVAL;
97 
98 	sc->disk = disk_alloc();
99 	if (sc->disk == NULL)
100 		return ENOMEM;
101 	sc->disk->d_name = "cfid";
102 	sc->disk->d_unit = device_get_unit(dev);
103 	sc->disk->d_open = cfi_disk_open;
104 	sc->disk->d_close = cfi_disk_close;
105 	sc->disk->d_strategy = cfi_disk_strategy;
106 	sc->disk->d_ioctl = cfi_disk_ioctl;
107 	sc->disk->d_dump = NULL;		/* NB: no dumps */
108 	sc->disk->d_getattr = cfi_disk_getattr;
109 	sc->disk->d_sectorsize = CFI_DISK_SECSIZE;
110 	sc->disk->d_mediasize = sc->parent->sc_size;
111 	sc->disk->d_maxsize = CFI_DISK_MAXIOSIZE;
112 	/* NB: use stripesize to hold the erase/region size */
113 	if (sc->parent->sc_regions) {
114 		/*
115 		 * Multiple regions, use the last one.  This is a
116 		 * total hack as it's (presently) used only by
117 		 * geom_redboot to locate the FIS directory which
118 		 * lies at the start of the last erase region.
119 		 */
120 		sc->disk->d_stripesize =
121 		    sc->parent->sc_region[sc->parent->sc_regions-1].r_blksz;
122 	} else
123 		sc->disk->d_stripesize = sc->disk->d_mediasize;
124 	sc->disk->d_drv1 = sc;
125 	disk_create(sc->disk, DISK_VERSION);
126 
127 	mtx_init(&sc->qlock, "CFID I/O lock", NULL, MTX_DEF);
128 	bioq_init(&sc->bioq);
129 
130 	sc->tq = taskqueue_create("cfid_taskq", M_NOWAIT,
131 		taskqueue_thread_enqueue, &sc->tq);
132 	taskqueue_start_threads(&sc->tq, 1, PI_DISK, "cfid taskq");
133 
134 	TASK_INIT(&sc->iotask, 0, cfi_io_proc, sc);
135 
136 	return 0;
137 }
138 
139 static int
140 cfi_disk_detach(device_t dev)
141 {
142 	struct cfi_disk_softc *sc = device_get_softc(dev);
143 
144 	if (sc->flags & CFI_DISK_OPEN)
145 		return EBUSY;
146 	taskqueue_free(sc->tq);
147 	/* XXX drain bioq */
148 	disk_destroy(sc->disk);
149 	mtx_destroy(&sc->qlock);
150 	return 0;
151 }
152 
153 static int
154 cfi_disk_open(struct disk *dp)
155 {
156 	struct cfi_disk_softc *sc = dp->d_drv1;
157 
158 	/* XXX no interlock with /dev/cfi */
159 	sc->flags |= CFI_DISK_OPEN;
160 	return 0;
161 }
162 
163 static int
164 cfi_disk_close(struct disk *dp)
165 {
166 	struct cfi_disk_softc *sc = dp->d_drv1;
167 
168 	sc->flags &= ~CFI_DISK_OPEN;
169 	return 0;
170 }
171 
172 static void
173 cfi_disk_read(struct cfi_softc *sc, struct bio *bp)
174 {
175 	long resid;
176 
177 	KASSERT(sc->sc_width == 1 || sc->sc_width == 2 || sc->sc_width == 4,
178 	    ("sc_width %d", sc->sc_width));
179 
180 	if (sc->sc_writing) {
181 		bp->bio_error = cfi_block_finish(sc);
182 		if (bp->bio_error) {
183 			bp->bio_flags |= BIO_ERROR;
184 			goto done;
185 		}
186 	}
187 	if (bp->bio_offset > sc->sc_size) {
188 		bp->bio_flags |= BIO_ERROR;
189 		bp->bio_error = EIO;
190 		goto done;
191 	}
192 	resid = bp->bio_bcount;
193 	if (sc->sc_width == 1) {
194 		uint8_t *dp = (uint8_t *)bp->bio_data;
195 		while (resid > 0 && bp->bio_offset < sc->sc_size) {
196 			*dp++ = cfi_read_raw(sc, bp->bio_offset);
197 			bp->bio_offset += 1, resid -= 1;
198 		}
199 	} else if (sc->sc_width == 2) {
200 		uint16_t *dp = (uint16_t *)bp->bio_data;
201 		while (resid > 0 && bp->bio_offset < sc->sc_size) {
202 			*dp++ = cfi_read_raw(sc, bp->bio_offset);
203 			bp->bio_offset += 2, resid -= 2;
204 		}
205 	} else {
206 		uint32_t *dp = (uint32_t *)bp->bio_data;
207 		while (resid > 0 && bp->bio_offset < sc->sc_size) {
208 			*dp++ = cfi_read_raw(sc, bp->bio_offset);
209 			bp->bio_offset += 4, resid -= 4;
210 		}
211 	}
212 	bp->bio_resid = resid;
213 done:
214 	biodone(bp);
215 }
216 
217 static void
218 cfi_disk_write(struct cfi_softc *sc, struct bio *bp)
219 {
220 	long resid;
221 	u_int top;
222 
223 	KASSERT(sc->sc_width == 1 || sc->sc_width == 2 || sc->sc_width == 4,
224 	    ("sc_width %d", sc->sc_width));
225 
226 	if (bp->bio_offset > sc->sc_size) {
227 		bp->bio_flags |= BIO_ERROR;
228 		bp->bio_error = EIO;
229 		goto done;
230 	}
231 	resid = bp->bio_bcount;
232 	while (resid > 0) {
233 		/*
234 		 * Finish the current block if we're about to write
235 		 * to a different block.
236 		 */
237 		if (sc->sc_writing) {
238 			top = sc->sc_wrofs + sc->sc_wrbufsz;
239 			if (bp->bio_offset < sc->sc_wrofs ||
240 			    bp->bio_offset >= top)
241 				cfi_block_finish(sc);
242 		}
243 
244 		/* Start writing to a (new) block if applicable. */
245 		if (!sc->sc_writing) {
246 			bp->bio_error = cfi_block_start(sc, bp->bio_offset);
247 			if (bp->bio_error) {
248 				bp->bio_flags |= BIO_ERROR;
249 				goto done;
250 			}
251 		}
252 
253 		top = sc->sc_wrofs + sc->sc_wrbufsz;
254 		bcopy(bp->bio_data,
255 		    sc->sc_wrbuf + bp->bio_offset - sc->sc_wrofs,
256 		    MIN(top - bp->bio_offset, resid));
257 		resid -= MIN(top - bp->bio_offset, resid);
258 	}
259 	bp->bio_resid = resid;
260 done:
261 	biodone(bp);
262 }
263 
264 static void
265 cfi_io_proc(void *arg, int pending)
266 {
267 	struct cfi_disk_softc *sc = arg;
268 	struct cfi_softc *cfi = sc->parent;
269 	struct bio *bp;
270 
271 	for (;;) {
272 		mtx_lock(&sc->qlock);
273 		bp = bioq_takefirst(&sc->bioq);
274 		mtx_unlock(&sc->qlock);
275 		if (bp == NULL)
276 			break;
277 
278 		switch (bp->bio_cmd) {
279 		case BIO_READ:
280 			cfi_disk_read(cfi, bp);
281 			break;
282 		case BIO_WRITE:
283 			cfi_disk_write(cfi, bp);
284 			break;
285 		}
286 	}
287 }
288 
289 static int
290 cfi_disk_getattr(struct bio *bp)
291 {
292 	struct cfi_disk_softc *dsc;
293 	struct cfi_softc *sc;
294 	device_t dev;
295 
296 	if (bp->bio_disk == NULL || bp->bio_disk->d_drv1 == NULL)
297 		return (ENXIO);
298 
299 	dsc = bp->bio_disk->d_drv1;
300 	sc = dsc->parent;
301 	dev = sc->sc_dev;
302 
303 	if (strcmp(bp->bio_attribute, "CFI::device") == 0) {
304 		if (bp->bio_length != sizeof(dev))
305 			return (EFAULT);
306 		bcopy(&dev, bp->bio_data, sizeof(dev));
307 	} else
308 		return (-1);
309 	return (0);
310 }
311 
312 static void
313 cfi_disk_strategy(struct bio *bp)
314 {
315 	struct cfi_disk_softc *sc = bp->bio_disk->d_drv1;
316 
317 	if (sc == NULL) {
318 		biofinish(bp, NULL, EINVAL);
319 		return;
320 	}
321 	if (bp->bio_bcount == 0) {
322 		bp->bio_resid = bp->bio_bcount;
323 		biodone(bp);
324 		return;
325 	}
326 	switch (bp->bio_cmd) {
327 	case BIO_READ:
328 	case BIO_WRITE:
329 		mtx_lock(&sc->qlock);
330 		/* no value in sorting requests? */
331 		bioq_insert_tail(&sc->bioq, bp);
332 		mtx_unlock(&sc->qlock);
333 		taskqueue_enqueue(sc->tq, &sc->iotask);
334 		break;
335 	default:
336 		biofinish(bp, NULL, EOPNOTSUPP);
337 		break;
338 	}
339 }
340 
341 static int
342 cfi_disk_ioctl(struct disk *dp, u_long cmd, void *data, int fflag,
343 	struct thread *td)
344 {
345 	return EINVAL;
346 }
347 
348 static device_method_t cfi_disk_methods[] = {
349 	DEVMETHOD(device_probe,		cfi_disk_probe),
350 	DEVMETHOD(device_attach,	cfi_disk_attach),
351 	DEVMETHOD(device_detach,	cfi_disk_detach),
352 	{ 0, 0 }
353 };
354 static driver_t cfi_disk_driver = {
355 	"cfid",
356 	cfi_disk_methods,
357 	sizeof(struct cfi_disk_softc),
358 };
359 DRIVER_MODULE(cfid, cfi, cfi_disk_driver, NULL, NULL);
360