1 | /* $NetBSD: md.c,v 1.78 2016/07/27 05:14:40 pgoyette Exp $ */ |
2 | |
3 | /* |
4 | * Copyright (c) 1995 Gordon W. Ross, Leo Weppelman. |
5 | * All rights reserved. |
6 | * |
7 | * Redistribution and use in source and binary forms, with or without |
8 | * modification, are permitted provided that the following conditions |
9 | * are met: |
10 | * 1. Redistributions of source code must retain the above copyright |
11 | * notice, this list of conditions and the following disclaimer. |
12 | * 2. Redistributions in binary form must reproduce the above copyright |
13 | * notice, this list of conditions and the following disclaimer in the |
14 | * documentation and/or other materials provided with the distribution. |
15 | * |
16 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
17 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
18 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
19 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
20 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
21 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
22 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
23 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
24 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
25 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
26 | */ |
27 | |
28 | /* |
29 | * This implements a general-purpose memory-disk. |
30 | * See md.h for notes on the config types. |
31 | * |
32 | * Note that this driver provides the same functionality |
33 | * as the MFS filesystem hack, but this is better because |
34 | * you can use this for any filesystem type you'd like! |
35 | * |
36 | * Credit for most of the kmem ramdisk code goes to: |
37 | * Leo Weppelman (atari) and Phil Nelson (pc532) |
38 | * Credit for the ideas behind the "user space memory" code goes |
39 | * to the authors of the MFS implementation. |
40 | */ |
41 | |
42 | #include <sys/cdefs.h> |
43 | __KERNEL_RCSID(0, "$NetBSD: md.c,v 1.78 2016/07/27 05:14:40 pgoyette Exp $" ); |
44 | |
45 | #ifdef _KERNEL_OPT |
46 | #include "opt_md.h" |
47 | #else |
48 | #define MEMORY_DISK_SERVER 1 |
49 | #endif |
50 | |
51 | #include <sys/param.h> |
52 | #include <sys/kernel.h> |
53 | #include <sys/malloc.h> |
54 | #include <sys/systm.h> |
55 | #include <sys/buf.h> |
56 | #include <sys/bufq.h> |
57 | #include <sys/device.h> |
58 | #include <sys/disk.h> |
59 | #include <sys/stat.h> |
60 | #include <sys/proc.h> |
61 | #include <sys/conf.h> |
62 | #include <sys/disklabel.h> |
63 | |
64 | #include <uvm/uvm_extern.h> |
65 | |
66 | #include <dev/md.h> |
67 | |
68 | #include "ioconf.h" |
69 | /* |
70 | * The user-space functionality is included by default. |
71 | * Use `options MEMORY_DISK_SERVER=0' to turn it off. |
72 | */ |
73 | #ifndef MEMORY_DISK_SERVER |
74 | #error MEMORY_DISK_SERVER should be defined by opt_md.h |
75 | #endif /* MEMORY_DISK_SERVER */ |
76 | |
77 | /* |
78 | * We should use the raw partition for ioctl. |
79 | */ |
80 | #define MD_UNIT(unit) DISKUNIT(unit) |
81 | |
82 | /* autoconfig stuff... */ |
83 | |
84 | struct md_softc { |
85 | device_t sc_dev; /* Self. */ |
86 | struct disk sc_dkdev; /* hook for generic disk handling */ |
87 | struct md_conf sc_md; |
88 | kmutex_t sc_lock; /* Protect self. */ |
89 | kcondvar_t sc_cv; /* Wait here for work. */ |
90 | struct bufq_state *sc_buflist; |
91 | }; |
92 | /* shorthand for fields in sc_md: */ |
93 | #define sc_addr sc_md.md_addr |
94 | #define sc_size sc_md.md_size |
95 | #define sc_type sc_md.md_type |
96 | |
97 | static void md_attach(device_t, device_t, void *); |
98 | static int md_detach(device_t, int); |
99 | |
100 | static dev_type_open(mdopen); |
101 | static dev_type_close(mdclose); |
102 | static dev_type_read(mdread); |
103 | static dev_type_write(mdwrite); |
104 | static dev_type_ioctl(mdioctl); |
105 | static dev_type_strategy(mdstrategy); |
106 | static dev_type_size(mdsize); |
107 | |
108 | const struct bdevsw md_bdevsw = { |
109 | .d_open = mdopen, |
110 | .d_close = mdclose, |
111 | .d_strategy = mdstrategy, |
112 | .d_ioctl = mdioctl, |
113 | .d_dump = nodump, |
114 | .d_psize = mdsize, |
115 | .d_discard = nodiscard, |
116 | .d_flag = D_DISK | D_MPSAFE |
117 | }; |
118 | |
119 | const struct cdevsw md_cdevsw = { |
120 | .d_open = mdopen, |
121 | .d_close = mdclose, |
122 | .d_read = mdread, |
123 | .d_write = mdwrite, |
124 | .d_ioctl = mdioctl, |
125 | .d_stop = nostop, |
126 | .d_tty = notty, |
127 | .d_poll = nopoll, |
128 | .d_mmap = nommap, |
129 | .d_kqfilter = nokqfilter, |
130 | .d_discard = nodiscard, |
131 | .d_flag = D_DISK |
132 | }; |
133 | |
134 | static struct dkdriver mddkdriver = { |
135 | .d_strategy = mdstrategy |
136 | }; |
137 | |
138 | extern struct cfdriver md_cd; |
139 | CFATTACH_DECL3_NEW(md, sizeof(struct md_softc), |
140 | 0, md_attach, md_detach, NULL, NULL, NULL, DVF_DETACH_SHUTDOWN); |
141 | |
142 | static kmutex_t md_device_lock; /* Protect unit creation / deletion. */ |
143 | extern size_t md_root_size; |
144 | |
145 | static void md_set_disklabel(struct md_softc *); |
146 | |
147 | /* |
148 | * This is called if we are configured as a pseudo-device |
149 | */ |
150 | void |
151 | mdattach(int n) |
152 | { |
153 | |
154 | mutex_init(&md_device_lock, MUTEX_DEFAULT, IPL_NONE); |
155 | if (config_cfattach_attach(md_cd.cd_name, &md_ca)) { |
156 | aprint_error("%s: cfattach_attach failed\n" , md_cd.cd_name); |
157 | return; |
158 | } |
159 | } |
160 | |
161 | static void |
162 | md_attach(device_t parent, device_t self, void *aux) |
163 | { |
164 | struct md_softc *sc = device_private(self); |
165 | |
166 | sc->sc_dev = self; |
167 | sc->sc_type = MD_UNCONFIGURED; |
168 | mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_NONE); |
169 | cv_init(&sc->sc_cv, "mdidle" ); |
170 | bufq_alloc(&sc->sc_buflist, "fcfs" , 0); |
171 | |
172 | /* XXX - Could accept aux info here to set the config. */ |
173 | #ifdef MEMORY_DISK_HOOKS |
174 | /* |
175 | * This external function might setup a pre-loaded disk. |
176 | * All it would need to do is setup the md_conf struct. |
177 | * See sys/dev/md_root.c for an example. |
178 | */ |
179 | md_attach_hook(device_unit(self), &sc->sc_md); |
180 | #endif |
181 | |
182 | /* |
183 | * Initialize and attach the disk structure. |
184 | */ |
185 | disk_init(&sc->sc_dkdev, device_xname(self), &mddkdriver); |
186 | disk_attach(&sc->sc_dkdev); |
187 | |
188 | if (sc->sc_type != MD_UNCONFIGURED) |
189 | md_set_disklabel(sc); |
190 | |
191 | if (!pmf_device_register(self, NULL, NULL)) |
192 | aprint_error_dev(self, "couldn't establish power handler\n" ); |
193 | } |
194 | |
195 | static int |
196 | md_detach(device_t self, int flags) |
197 | { |
198 | struct md_softc *sc = device_private(self); |
199 | int rc; |
200 | |
201 | rc = 0; |
202 | mutex_enter(&sc->sc_dkdev.dk_openlock); |
203 | if (sc->sc_dkdev.dk_openmask == 0 && sc->sc_type == MD_UNCONFIGURED) |
204 | ; /* nothing to do */ |
205 | else if ((flags & DETACH_FORCE) == 0) |
206 | rc = EBUSY; |
207 | mutex_exit(&sc->sc_dkdev.dk_openlock); |
208 | |
209 | if (rc != 0) |
210 | return rc; |
211 | |
212 | pmf_device_deregister(self); |
213 | disk_detach(&sc->sc_dkdev); |
214 | disk_destroy(&sc->sc_dkdev); |
215 | bufq_free(sc->sc_buflist); |
216 | mutex_destroy(&sc->sc_lock); |
217 | cv_destroy(&sc->sc_cv); |
218 | return 0; |
219 | } |
220 | |
221 | /* |
222 | * operational routines: |
223 | * open, close, read, write, strategy, |
224 | * ioctl, dump, size |
225 | */ |
226 | |
227 | #if MEMORY_DISK_SERVER |
228 | static int md_server_loop(struct md_softc *sc); |
229 | static int md_ioctl_server(struct md_softc *sc, struct md_conf *umd, |
230 | struct lwp *l); |
231 | #endif /* MEMORY_DISK_SERVER */ |
232 | static int md_ioctl_kalloc(struct md_softc *sc, struct md_conf *umd, |
233 | struct lwp *l); |
234 | |
235 | static int |
236 | mdsize(dev_t dev) |
237 | { |
238 | struct md_softc *sc; |
239 | int res; |
240 | |
241 | sc = device_lookup_private(&md_cd, MD_UNIT(dev)); |
242 | if (sc == NULL) |
243 | return 0; |
244 | |
245 | mutex_enter(&sc->sc_lock); |
246 | if (sc->sc_type == MD_UNCONFIGURED) |
247 | res = 0; |
248 | else |
249 | res = sc->sc_size >> DEV_BSHIFT; |
250 | mutex_exit(&sc->sc_lock); |
251 | |
252 | return res; |
253 | } |
254 | |
255 | static int |
256 | mdopen(dev_t dev, int flag, int fmt, struct lwp *l) |
257 | { |
258 | int unit; |
259 | int part = DISKPART(dev); |
260 | int pmask = 1 << part; |
261 | cfdata_t cf; |
262 | struct md_softc *sc; |
263 | struct disk *dk; |
264 | #ifdef MEMORY_DISK_HOOKS |
265 | bool configured; |
266 | #endif |
267 | |
268 | mutex_enter(&md_device_lock); |
269 | unit = MD_UNIT(dev); |
270 | sc = device_lookup_private(&md_cd, unit); |
271 | if (sc == NULL) { |
272 | if (part != RAW_PART) { |
273 | mutex_exit(&md_device_lock); |
274 | return ENXIO; |
275 | } |
276 | cf = malloc(sizeof(*cf), M_DEVBUF, M_WAITOK); |
277 | cf->cf_name = md_cd.cd_name; |
278 | cf->cf_atname = md_cd.cd_name; |
279 | cf->cf_unit = unit; |
280 | cf->cf_fstate = FSTATE_STAR; |
281 | sc = device_private(config_attach_pseudo(cf)); |
282 | if (sc == NULL) { |
283 | mutex_exit(&md_device_lock); |
284 | return ENOMEM; |
285 | } |
286 | } |
287 | |
288 | dk = &sc->sc_dkdev; |
289 | |
290 | /* |
291 | * The raw partition is used for ioctl to configure. |
292 | */ |
293 | if (part == RAW_PART) |
294 | goto ok; |
295 | |
296 | #ifdef MEMORY_DISK_HOOKS |
297 | /* Call the open hook to allow loading the device. */ |
298 | configured = (sc->sc_type != MD_UNCONFIGURED); |
299 | md_open_hook(unit, &sc->sc_md); |
300 | /* initialize disklabel if the device is configured in open hook */ |
301 | if (!configured && sc->sc_type != MD_UNCONFIGURED) |
302 | md_set_disklabel(sc); |
303 | #endif |
304 | |
305 | /* |
306 | * This is a normal, "slave" device, so |
307 | * enforce initialized. |
308 | */ |
309 | if (sc->sc_type == MD_UNCONFIGURED) { |
310 | mutex_exit(&md_device_lock); |
311 | return ENXIO; |
312 | } |
313 | |
314 | ok: |
315 | /* XXX duplicates code in dk_open(). Call dk_open(), instead? */ |
316 | mutex_enter(&dk->dk_openlock); |
317 | /* Mark our unit as open. */ |
318 | switch (fmt) { |
319 | case S_IFCHR: |
320 | dk->dk_copenmask |= pmask; |
321 | break; |
322 | case S_IFBLK: |
323 | dk->dk_bopenmask |= pmask; |
324 | break; |
325 | } |
326 | |
327 | dk->dk_openmask = dk->dk_copenmask | dk->dk_bopenmask; |
328 | |
329 | mutex_exit(&dk->dk_openlock); |
330 | mutex_exit(&md_device_lock); |
331 | return 0; |
332 | } |
333 | |
334 | static int |
335 | mdclose(dev_t dev, int flag, int fmt, struct lwp *l) |
336 | { |
337 | int part = DISKPART(dev); |
338 | int pmask = 1 << part; |
339 | int error; |
340 | cfdata_t cf; |
341 | struct md_softc *sc; |
342 | struct disk *dk; |
343 | |
344 | sc = device_lookup_private(&md_cd, MD_UNIT(dev)); |
345 | if (sc == NULL) |
346 | return ENXIO; |
347 | |
348 | dk = &sc->sc_dkdev; |
349 | |
350 | mutex_enter(&dk->dk_openlock); |
351 | |
352 | switch (fmt) { |
353 | case S_IFCHR: |
354 | dk->dk_copenmask &= ~pmask; |
355 | break; |
356 | case S_IFBLK: |
357 | dk->dk_bopenmask &= ~pmask; |
358 | break; |
359 | } |
360 | dk->dk_openmask = dk->dk_copenmask | dk->dk_bopenmask; |
361 | if (dk->dk_openmask != 0) { |
362 | mutex_exit(&dk->dk_openlock); |
363 | return 0; |
364 | } |
365 | |
366 | mutex_exit(&dk->dk_openlock); |
367 | |
368 | mutex_enter(&md_device_lock); |
369 | cf = device_cfdata(sc->sc_dev); |
370 | error = config_detach(sc->sc_dev, DETACH_QUIET); |
371 | if (! error) |
372 | free(cf, M_DEVBUF); |
373 | mutex_exit(&md_device_lock); |
374 | return error; |
375 | } |
376 | |
377 | static int |
378 | mdread(dev_t dev, struct uio *uio, int flags) |
379 | { |
380 | struct md_softc *sc; |
381 | |
382 | sc = device_lookup_private(&md_cd, MD_UNIT(dev)); |
383 | |
384 | if (sc == NULL || sc->sc_type == MD_UNCONFIGURED) |
385 | return ENXIO; |
386 | |
387 | return (physio(mdstrategy, NULL, dev, B_READ, minphys, uio)); |
388 | } |
389 | |
390 | static int |
391 | mdwrite(dev_t dev, struct uio *uio, int flags) |
392 | { |
393 | struct md_softc *sc; |
394 | |
395 | sc = device_lookup_private(&md_cd, MD_UNIT(dev)); |
396 | |
397 | if (sc == NULL || sc->sc_type == MD_UNCONFIGURED) |
398 | return ENXIO; |
399 | |
400 | return (physio(mdstrategy, NULL, dev, B_WRITE, minphys, uio)); |
401 | } |
402 | |
403 | /* |
404 | * Handle I/O requests, either directly, or |
405 | * by passing them to the server process. |
406 | */ |
407 | static void |
408 | mdstrategy(struct buf *bp) |
409 | { |
410 | struct md_softc *sc; |
411 | void * addr; |
412 | size_t off, xfer; |
413 | bool is_read; |
414 | |
415 | sc = device_lookup_private(&md_cd, MD_UNIT(bp->b_dev)); |
416 | |
417 | if (sc == NULL || sc->sc_type == MD_UNCONFIGURED) { |
418 | bp->b_error = ENXIO; |
419 | goto done; |
420 | } |
421 | |
422 | mutex_enter(&sc->sc_lock); |
423 | |
424 | switch (sc->sc_type) { |
425 | #if MEMORY_DISK_SERVER |
426 | case MD_UMEM_SERVER: |
427 | /* Just add this job to the server's queue. */ |
428 | bufq_put(sc->sc_buflist, bp); |
429 | cv_signal(&sc->sc_cv); |
430 | mutex_exit(&sc->sc_lock); |
431 | /* see md_server_loop() */ |
432 | /* no biodone in this case */ |
433 | return; |
434 | #endif /* MEMORY_DISK_SERVER */ |
435 | |
436 | case MD_KMEM_FIXED: |
437 | case MD_KMEM_ALLOCATED: |
438 | /* These are in kernel space. Access directly. */ |
439 | is_read = ((bp->b_flags & B_READ) == B_READ); |
440 | bp->b_resid = bp->b_bcount; |
441 | off = (bp->b_blkno << DEV_BSHIFT); |
442 | if (off >= sc->sc_size) { |
443 | if (is_read) |
444 | break; /* EOF */ |
445 | goto set_eio; |
446 | } |
447 | xfer = bp->b_resid; |
448 | if (xfer > (sc->sc_size - off)) |
449 | xfer = (sc->sc_size - off); |
450 | addr = (char *)sc->sc_addr + off; |
451 | disk_busy(&sc->sc_dkdev); |
452 | if (is_read) |
453 | memcpy(bp->b_data, addr, xfer); |
454 | else |
455 | memcpy(addr, bp->b_data, xfer); |
456 | disk_unbusy(&sc->sc_dkdev, xfer, is_read); |
457 | bp->b_resid -= xfer; |
458 | break; |
459 | |
460 | default: |
461 | bp->b_resid = bp->b_bcount; |
462 | set_eio: |
463 | bp->b_error = EIO; |
464 | break; |
465 | } |
466 | mutex_exit(&sc->sc_lock); |
467 | |
468 | done: |
469 | |
470 | biodone(bp); |
471 | } |
472 | |
473 | static int |
474 | mdioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l) |
475 | { |
476 | struct md_softc *sc; |
477 | struct md_conf *umd; |
478 | int error; |
479 | |
480 | if ((sc = device_lookup_private(&md_cd, MD_UNIT(dev))) == NULL) |
481 | return ENXIO; |
482 | |
483 | mutex_enter(&sc->sc_lock); |
484 | if (sc->sc_type != MD_UNCONFIGURED) { |
485 | error = disk_ioctl(&sc->sc_dkdev, dev, cmd, data, flag, l); |
486 | if (error != EPASSTHROUGH) { |
487 | mutex_exit(&sc->sc_lock); |
488 | return 0; |
489 | } |
490 | } |
491 | |
492 | /* If this is not the raw partition, punt! */ |
493 | if (DISKPART(dev) != RAW_PART) { |
494 | mutex_exit(&sc->sc_lock); |
495 | return ENOTTY; |
496 | } |
497 | |
498 | umd = (struct md_conf *)data; |
499 | error = EINVAL; |
500 | switch (cmd) { |
501 | case MD_GETCONF: |
502 | *umd = sc->sc_md; |
503 | error = 0; |
504 | break; |
505 | |
506 | case MD_SETCONF: |
507 | /* Can only set it once. */ |
508 | if (sc->sc_type != MD_UNCONFIGURED) |
509 | break; |
510 | switch (umd->md_type) { |
511 | case MD_KMEM_ALLOCATED: |
512 | error = md_ioctl_kalloc(sc, umd, l); |
513 | break; |
514 | #if MEMORY_DISK_SERVER |
515 | case MD_UMEM_SERVER: |
516 | error = md_ioctl_server(sc, umd, l); |
517 | break; |
518 | #endif /* MEMORY_DISK_SERVER */ |
519 | default: |
520 | break; |
521 | } |
522 | break; |
523 | } |
524 | mutex_exit(&sc->sc_lock); |
525 | return error; |
526 | } |
527 | |
528 | static void |
529 | md_set_disklabel(struct md_softc *sc) |
530 | { |
531 | struct disk_geom *dg = &sc->sc_dkdev.dk_geom; |
532 | struct disklabel *lp = sc->sc_dkdev.dk_label; |
533 | struct partition *pp; |
534 | |
535 | memset(lp, 0, sizeof(*lp)); |
536 | |
537 | lp->d_secsize = DEV_BSIZE; |
538 | lp->d_secperunit = sc->sc_size / DEV_BSIZE; |
539 | if (lp->d_secperunit >= (32*64)) { |
540 | lp->d_nsectors = 32; |
541 | lp->d_ntracks = 64; |
542 | lp->d_ncylinders = lp->d_secperunit / (32*64); |
543 | } else { |
544 | lp->d_nsectors = 1; |
545 | lp->d_ntracks = 1; |
546 | lp->d_ncylinders = lp->d_secperunit; |
547 | } |
548 | lp->d_secpercyl = lp->d_ntracks*lp->d_nsectors; |
549 | |
550 | strncpy(lp->d_typename, md_cd.cd_name, sizeof(lp->d_typename)); |
551 | lp->d_type = DKTYPE_MD; |
552 | strncpy(lp->d_packname, "fictitious" , sizeof(lp->d_packname)); |
553 | lp->d_rpm = 3600; |
554 | lp->d_interleave = 1; |
555 | lp->d_flags = 0; |
556 | |
557 | pp = &lp->d_partitions[0]; |
558 | pp->p_offset = 0; |
559 | pp->p_size = lp->d_secperunit; |
560 | pp->p_fstype = FS_BSDFFS; |
561 | |
562 | pp = &lp->d_partitions[RAW_PART]; |
563 | pp->p_offset = 0; |
564 | pp->p_size = lp->d_secperunit; |
565 | pp->p_fstype = FS_UNUSED; |
566 | |
567 | lp->d_npartitions = RAW_PART+1; |
568 | lp->d_magic = DISKMAGIC; |
569 | lp->d_magic2 = DISKMAGIC; |
570 | lp->d_checksum = dkcksum(lp); |
571 | |
572 | memset(dg, 0, sizeof(*dg)); |
573 | |
574 | dg->dg_secsize = lp->d_secsize; |
575 | dg->dg_secperunit = lp->d_secperunit; |
576 | dg->dg_nsectors = lp->d_nsectors; |
577 | dg->dg_ntracks = lp->d_ntracks = 64;; |
578 | dg->dg_ncylinders = lp->d_ncylinders; |
579 | |
580 | disk_set_info(sc->sc_dev, &sc->sc_dkdev, NULL); |
581 | } |
582 | |
583 | /* |
584 | * Handle ioctl MD_SETCONF for (sc_type == MD_KMEM_ALLOCATED) |
585 | * Just allocate some kernel memory and return. |
586 | */ |
587 | static int |
588 | md_ioctl_kalloc(struct md_softc *sc, struct md_conf *umd, |
589 | struct lwp *l) |
590 | { |
591 | vaddr_t addr; |
592 | vsize_t size; |
593 | |
594 | mutex_exit(&sc->sc_lock); |
595 | |
596 | /* Sanity check the size. */ |
597 | size = umd->md_size; |
598 | addr = uvm_km_alloc(kernel_map, size, 0, UVM_KMF_WIRED|UVM_KMF_ZERO); |
599 | |
600 | mutex_enter(&sc->sc_lock); |
601 | |
602 | if (!addr) |
603 | return ENOMEM; |
604 | |
605 | /* If another thread beat us to configure this unit: fail. */ |
606 | if (sc->sc_type != MD_UNCONFIGURED) { |
607 | uvm_km_free(kernel_map, addr, size, UVM_KMF_WIRED); |
608 | return EINVAL; |
609 | } |
610 | |
611 | /* This unit is now configured. */ |
612 | sc->sc_addr = (void *)addr; /* kernel space */ |
613 | sc->sc_size = (size_t)size; |
614 | sc->sc_type = MD_KMEM_ALLOCATED; |
615 | md_set_disklabel(sc); |
616 | return 0; |
617 | } |
618 | |
619 | #if MEMORY_DISK_SERVER |
620 | |
621 | /* |
622 | * Handle ioctl MD_SETCONF for (sc_type == MD_UMEM_SERVER) |
623 | * Set config, then become the I/O server for this unit. |
624 | */ |
625 | static int |
626 | md_ioctl_server(struct md_softc *sc, struct md_conf *umd, |
627 | struct lwp *l) |
628 | { |
629 | vaddr_t end; |
630 | int error; |
631 | |
632 | KASSERT(mutex_owned(&sc->sc_lock)); |
633 | |
634 | /* Sanity check addr, size. */ |
635 | end = (vaddr_t) ((char *)umd->md_addr + umd->md_size); |
636 | |
637 | if ((end >= VM_MAXUSER_ADDRESS) || |
638 | (end < ((vaddr_t) umd->md_addr)) ) |
639 | return EINVAL; |
640 | |
641 | /* This unit is now configured. */ |
642 | sc->sc_addr = umd->md_addr; /* user space */ |
643 | sc->sc_size = umd->md_size; |
644 | sc->sc_type = MD_UMEM_SERVER; |
645 | md_set_disklabel(sc); |
646 | |
647 | /* Become the server daemon */ |
648 | error = md_server_loop(sc); |
649 | |
650 | /* This server is now going away! */ |
651 | sc->sc_type = MD_UNCONFIGURED; |
652 | sc->sc_addr = 0; |
653 | sc->sc_size = 0; |
654 | |
655 | return (error); |
656 | } |
657 | |
658 | static int |
659 | md_server_loop(struct md_softc *sc) |
660 | { |
661 | struct buf *bp; |
662 | void *addr; /* user space address */ |
663 | size_t off; /* offset into "device" */ |
664 | size_t xfer; /* amount to transfer */ |
665 | int error; |
666 | bool is_read; |
667 | |
668 | KASSERT(mutex_owned(&sc->sc_lock)); |
669 | |
670 | for (;;) { |
671 | /* Wait for some work to arrive. */ |
672 | while ((bp = bufq_get(sc->sc_buflist)) == NULL) { |
673 | error = cv_wait_sig(&sc->sc_cv, &sc->sc_lock); |
674 | if (error) |
675 | return error; |
676 | } |
677 | |
678 | /* Do the transfer to/from user space. */ |
679 | mutex_exit(&sc->sc_lock); |
680 | error = 0; |
681 | is_read = ((bp->b_flags & B_READ) == B_READ); |
682 | bp->b_resid = bp->b_bcount; |
683 | off = (bp->b_blkno << DEV_BSHIFT); |
684 | if (off >= sc->sc_size) { |
685 | if (is_read) |
686 | goto done; /* EOF (not an error) */ |
687 | error = EIO; |
688 | goto done; |
689 | } |
690 | xfer = bp->b_resid; |
691 | if (xfer > (sc->sc_size - off)) |
692 | xfer = (sc->sc_size - off); |
693 | addr = (char *)sc->sc_addr + off; |
694 | disk_busy(&sc->sc_dkdev); |
695 | if (is_read) |
696 | error = copyin(addr, bp->b_data, xfer); |
697 | else |
698 | error = copyout(bp->b_data, addr, xfer); |
699 | disk_unbusy(&sc->sc_dkdev, (error ? 0 : xfer), is_read); |
700 | if (!error) |
701 | bp->b_resid -= xfer; |
702 | |
703 | done: |
704 | if (error) { |
705 | bp->b_error = error; |
706 | } |
707 | biodone(bp); |
708 | mutex_enter(&sc->sc_lock); |
709 | } |
710 | } |
711 | #endif /* MEMORY_DISK_SERVER */ |
712 | |