ctl_backend_ramdisk.c revision 279005
1/*-
2 * Copyright (c) 2003, 2008 Silicon Graphics International Corp.
3 * Copyright (c) 2012 The FreeBSD Foundation
4 * All rights reserved.
5 *
6 * Portions of this software were developed by Edward Tomasz Napierala
7 * under sponsorship from the FreeBSD Foundation.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions, and the following disclaimer,
14 *    without modification.
15 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
16 *    substantially similar to the "NO WARRANTY" disclaimer below
17 *    ("Disclaimer") and any redistribution must be conditioned upon
18 *    including a substantially similar Disclaimer requirement for further
19 *    binary redistribution.
20 *
21 * NO WARRANTY
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
25 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
26 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
30 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
31 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
32 * POSSIBILITY OF SUCH DAMAGES.
33 *
34 * $Id: //depot/users/kenm/FreeBSD-test2/sys/cam/ctl/ctl_backend_ramdisk.c#3 $
35 */
36/*
37 * CAM Target Layer backend for a "fake" ramdisk.
38 *
39 * Author: Ken Merry <ken@FreeBSD.org>
40 */
41
42#include <sys/cdefs.h>
43__FBSDID("$FreeBSD: stable/10/sys/cam/ctl/ctl_backend_ramdisk.c 279005 2015-02-19 14:40:50Z mav $");
44
45#include <sys/param.h>
46#include <sys/systm.h>
47#include <sys/kernel.h>
48#include <sys/condvar.h>
49#include <sys/types.h>
50#include <sys/lock.h>
51#include <sys/mutex.h>
52#include <sys/malloc.h>
53#include <sys/taskqueue.h>
54#include <sys/time.h>
55#include <sys/queue.h>
56#include <sys/conf.h>
57#include <sys/ioccom.h>
58#include <sys/module.h>
59
60#include <cam/scsi/scsi_all.h>
61#include <cam/ctl/ctl_io.h>
62#include <cam/ctl/ctl.h>
63#include <cam/ctl/ctl_util.h>
64#include <cam/ctl/ctl_backend.h>
65#include <cam/ctl/ctl_frontend_internal.h>
66#include <cam/ctl/ctl_debug.h>
67#include <cam/ctl/ctl_ioctl.h>
68#include <cam/ctl/ctl_error.h>
69
70typedef enum {
71	CTL_BE_RAMDISK_LUN_UNCONFIGURED	= 0x01,
72	CTL_BE_RAMDISK_LUN_CONFIG_ERR	= 0x02,
73	CTL_BE_RAMDISK_LUN_WAITING	= 0x04
74} ctl_be_ramdisk_lun_flags;
75
76struct ctl_be_ramdisk_lun {
77	char lunname[32];
78	uint64_t size_bytes;
79	uint64_t size_blocks;
80	struct ctl_be_ramdisk_softc *softc;
81	ctl_be_ramdisk_lun_flags flags;
82	STAILQ_ENTRY(ctl_be_ramdisk_lun) links;
83	struct ctl_be_lun ctl_be_lun;
84	struct taskqueue *io_taskqueue;
85	struct task io_task;
86	STAILQ_HEAD(, ctl_io_hdr) cont_queue;
87	struct mtx_padalign queue_lock;
88};
89
90struct ctl_be_ramdisk_softc {
91	struct mtx lock;
92	int rd_size;
93#ifdef CTL_RAMDISK_PAGES
94	uint8_t **ramdisk_pages;
95	int num_pages;
96#else
97	uint8_t *ramdisk_buffer;
98#endif
99	int num_luns;
100	STAILQ_HEAD(, ctl_be_ramdisk_lun) lun_list;
101};
102
103static struct ctl_be_ramdisk_softc rd_softc;
104
105int ctl_backend_ramdisk_init(void);
106void ctl_backend_ramdisk_shutdown(void);
107static int ctl_backend_ramdisk_move_done(union ctl_io *io);
108static int ctl_backend_ramdisk_submit(union ctl_io *io);
109static void ctl_backend_ramdisk_continue(union ctl_io *io);
110static int ctl_backend_ramdisk_ioctl(struct cdev *dev, u_long cmd,
111				     caddr_t addr, int flag, struct thread *td);
112static int ctl_backend_ramdisk_rm(struct ctl_be_ramdisk_softc *softc,
113				  struct ctl_lun_req *req);
114static int ctl_backend_ramdisk_create(struct ctl_be_ramdisk_softc *softc,
115				      struct ctl_lun_req *req, int do_wait);
116static int ctl_backend_ramdisk_modify(struct ctl_be_ramdisk_softc *softc,
117				  struct ctl_lun_req *req);
118static void ctl_backend_ramdisk_worker(void *context, int pending);
119static void ctl_backend_ramdisk_lun_shutdown(void *be_lun);
120static void ctl_backend_ramdisk_lun_config_status(void *be_lun,
121						  ctl_lun_config_status status);
122static int ctl_backend_ramdisk_config_write(union ctl_io *io);
123static int ctl_backend_ramdisk_config_read(union ctl_io *io);
124
125static struct ctl_backend_driver ctl_be_ramdisk_driver =
126{
127	.name = "ramdisk",
128	.flags = CTL_BE_FLAG_HAS_CONFIG,
129	.init = ctl_backend_ramdisk_init,
130	.data_submit = ctl_backend_ramdisk_submit,
131	.data_move_done = ctl_backend_ramdisk_move_done,
132	.config_read = ctl_backend_ramdisk_config_read,
133	.config_write = ctl_backend_ramdisk_config_write,
134	.ioctl = ctl_backend_ramdisk_ioctl
135};
136
137MALLOC_DEFINE(M_RAMDISK, "ramdisk", "Memory used for CTL RAMdisk");
138CTL_BACKEND_DECLARE(cbr, ctl_be_ramdisk_driver);
139
140int
141ctl_backend_ramdisk_init(void)
142{
143	struct ctl_be_ramdisk_softc *softc;
144#ifdef CTL_RAMDISK_PAGES
145	int i;
146#endif
147
148
149	softc = &rd_softc;
150
151	memset(softc, 0, sizeof(*softc));
152
153	mtx_init(&softc->lock, "ctlramdisk", NULL, MTX_DEF);
154
155	STAILQ_INIT(&softc->lun_list);
156	softc->rd_size = 1024 * 1024;
157#ifdef CTL_RAMDISK_PAGES
158	softc->num_pages = softc->rd_size / PAGE_SIZE;
159	softc->ramdisk_pages = (uint8_t **)malloc(sizeof(uint8_t *) *
160						  softc->num_pages, M_RAMDISK,
161						  M_WAITOK);
162	for (i = 0; i < softc->num_pages; i++)
163		softc->ramdisk_pages[i] = malloc(PAGE_SIZE, M_RAMDISK,M_WAITOK);
164#else
165	softc->ramdisk_buffer = (uint8_t *)malloc(softc->rd_size, M_RAMDISK,
166						  M_WAITOK);
167#endif
168
169	return (0);
170}
171
172void
173ctl_backend_ramdisk_shutdown(void)
174{
175	struct ctl_be_ramdisk_softc *softc;
176	struct ctl_be_ramdisk_lun *lun, *next_lun;
177#ifdef CTL_RAMDISK_PAGES
178	int i;
179#endif
180
181	softc = &rd_softc;
182
183	mtx_lock(&softc->lock);
184	for (lun = STAILQ_FIRST(&softc->lun_list); lun != NULL; lun = next_lun){
185		/*
186		 * Grab the next LUN.  The current LUN may get removed by
187		 * ctl_invalidate_lun(), which will call our LUN shutdown
188		 * routine, if there is no outstanding I/O for this LUN.
189		 */
190		next_lun = STAILQ_NEXT(lun, links);
191
192		/*
193		 * Drop our lock here.  Since ctl_invalidate_lun() can call
194		 * back into us, this could potentially lead to a recursive
195		 * lock of the same mutex, which would cause a hang.
196		 */
197		mtx_unlock(&softc->lock);
198		ctl_disable_lun(&lun->ctl_be_lun);
199		ctl_invalidate_lun(&lun->ctl_be_lun);
200		mtx_lock(&softc->lock);
201	}
202	mtx_unlock(&softc->lock);
203
204#ifdef CTL_RAMDISK_PAGES
205	for (i = 0; i < softc->num_pages; i++)
206		free(softc->ramdisk_pages[i], M_RAMDISK);
207
208	free(softc->ramdisk_pages, M_RAMDISK);
209#else
210	free(softc->ramdisk_buffer, M_RAMDISK);
211#endif
212
213	if (ctl_backend_deregister(&ctl_be_ramdisk_driver) != 0) {
214		printf("ctl_backend_ramdisk_shutdown: "
215		       "ctl_backend_deregister() failed!\n");
216	}
217}
218
219static int
220ctl_backend_ramdisk_move_done(union ctl_io *io)
221{
222	struct ctl_be_lun *ctl_be_lun;
223	struct ctl_be_ramdisk_lun *be_lun;
224#ifdef CTL_TIME_IO
225	struct bintime cur_bt;
226#endif
227
228	CTL_DEBUG_PRINT(("ctl_backend_ramdisk_move_done\n"));
229	ctl_be_lun = (struct ctl_be_lun *)io->io_hdr.ctl_private[
230		CTL_PRIV_BACKEND_LUN].ptr;
231	be_lun = (struct ctl_be_ramdisk_lun *)ctl_be_lun->be_lun;
232#ifdef CTL_TIME_IO
233	getbintime(&cur_bt);
234	bintime_sub(&cur_bt, &io->io_hdr.dma_start_bt);
235	bintime_add(&io->io_hdr.dma_bt, &cur_bt);
236	io->io_hdr.num_dmas++;
237#endif
238	if (io->scsiio.kern_sg_entries > 0)
239		free(io->scsiio.kern_data_ptr, M_RAMDISK);
240	io->scsiio.kern_rel_offset += io->scsiio.kern_data_len;
241	if (io->io_hdr.flags & CTL_FLAG_ABORT) {
242		;
243	} else if ((io->io_hdr.port_status == 0) &&
244	    ((io->io_hdr.status & CTL_STATUS_MASK) == CTL_STATUS_NONE)) {
245		if (io->io_hdr.ctl_private[CTL_PRIV_BACKEND].integer > 0) {
246			mtx_lock(&be_lun->queue_lock);
247			STAILQ_INSERT_TAIL(&be_lun->cont_queue,
248			    &io->io_hdr, links);
249			mtx_unlock(&be_lun->queue_lock);
250			taskqueue_enqueue(be_lun->io_taskqueue,
251			    &be_lun->io_task);
252			return (0);
253		}
254		ctl_set_success(&io->scsiio);
255	} else if ((io->io_hdr.port_status != 0) &&
256	    ((io->io_hdr.status & CTL_STATUS_MASK) == CTL_STATUS_NONE ||
257	     (io->io_hdr.status & CTL_STATUS_MASK) == CTL_SUCCESS)) {
258		/*
259		 * For hardware error sense keys, the sense key
260		 * specific value is defined to be a retry count,
261		 * but we use it to pass back an internal FETD
262		 * error code.  XXX KDM  Hopefully the FETD is only
263		 * using 16 bits for an error code, since that's
264		 * all the space we have in the sks field.
265		 */
266		ctl_set_internal_failure(&io->scsiio,
267					 /*sks_valid*/ 1,
268					 /*retry_count*/
269					 io->io_hdr.port_status);
270	}
271	ctl_data_submit_done(io);
272	return(0);
273}
274
275static int
276ctl_backend_ramdisk_submit(union ctl_io *io)
277{
278	struct ctl_be_lun *ctl_be_lun;
279	struct ctl_lba_len_flags *lbalen;
280
281	ctl_be_lun = (struct ctl_be_lun *)io->io_hdr.ctl_private[
282		CTL_PRIV_BACKEND_LUN].ptr;
283	lbalen = (struct ctl_lba_len_flags *)&io->io_hdr.ctl_private[CTL_PRIV_LBA_LEN];
284	if (lbalen->flags & CTL_LLF_VERIFY) {
285		ctl_set_success(&io->scsiio);
286		ctl_data_submit_done(io);
287		return (CTL_RETVAL_COMPLETE);
288	}
289	io->io_hdr.ctl_private[CTL_PRIV_BACKEND].integer =
290	    lbalen->len * ctl_be_lun->blocksize;
291	ctl_backend_ramdisk_continue(io);
292	return (CTL_RETVAL_COMPLETE);
293}
294
295static void
296ctl_backend_ramdisk_continue(union ctl_io *io)
297{
298	struct ctl_be_ramdisk_softc *softc;
299	int len, len_filled, sg_filled;
300#ifdef CTL_RAMDISK_PAGES
301	struct ctl_sg_entry *sg_entries;
302	int i;
303#endif
304
305	softc = &rd_softc;
306	len = io->io_hdr.ctl_private[CTL_PRIV_BACKEND].integer;
307#ifdef CTL_RAMDISK_PAGES
308	sg_filled = min(btoc(len), softc->num_pages);
309	if (sg_filled > 1) {
310		io->scsiio.kern_data_ptr = malloc(sizeof(struct ctl_sg_entry) *
311						  sg_filled, M_RAMDISK,
312						  M_WAITOK);
313		sg_entries = (struct ctl_sg_entry *)io->scsiio.kern_data_ptr;
314		for (i = 0, len_filled = 0; i < sg_filled; i++) {
315			sg_entries[i].addr = softc->ramdisk_pages[i];
316			sg_entries[i].len = MIN(PAGE_SIZE, len - len_filled);
317			len_filled += sg_entries[i].len;
318		}
319		io->io_hdr.flags |= CTL_FLAG_KDPTR_SGLIST;
320	} else {
321		sg_filled = 0;
322		len_filled = len;
323		io->scsiio.kern_data_ptr = softc->ramdisk_pages[0];
324	}
325#else
326	sg_filled = 0;
327	len_filled = min(len, softc->rd_size);
328	io->scsiio.kern_data_ptr = softc->ramdisk_buffer;
329#endif /* CTL_RAMDISK_PAGES */
330
331	io->scsiio.be_move_done = ctl_backend_ramdisk_move_done;
332	io->scsiio.kern_data_resid = 0;
333	io->scsiio.kern_data_len = len_filled;
334	io->scsiio.kern_sg_entries = sg_filled;
335	io->io_hdr.flags |= CTL_FLAG_ALLOCATED;
336	io->io_hdr.ctl_private[CTL_PRIV_BACKEND].integer -= len_filled;
337#ifdef CTL_TIME_IO
338	getbintime(&io->io_hdr.dma_start_bt);
339#endif
340	ctl_datamove(io);
341}
342
343static void
344ctl_backend_ramdisk_worker(void *context, int pending)
345{
346	struct ctl_be_ramdisk_softc *softc;
347	struct ctl_be_ramdisk_lun *be_lun;
348	union ctl_io *io;
349
350	be_lun = (struct ctl_be_ramdisk_lun *)context;
351	softc = be_lun->softc;
352
353	mtx_lock(&be_lun->queue_lock);
354	for (;;) {
355		io = (union ctl_io *)STAILQ_FIRST(&be_lun->cont_queue);
356		if (io != NULL) {
357			STAILQ_REMOVE(&be_lun->cont_queue, &io->io_hdr,
358				      ctl_io_hdr, links);
359
360			mtx_unlock(&be_lun->queue_lock);
361
362			ctl_backend_ramdisk_continue(io);
363
364			mtx_lock(&be_lun->queue_lock);
365			continue;
366		}
367
368		/*
369		 * If we get here, there is no work left in the queues, so
370		 * just break out and let the task queue go to sleep.
371		 */
372		break;
373	}
374	mtx_unlock(&be_lun->queue_lock);
375}
376
377static int
378ctl_backend_ramdisk_ioctl(struct cdev *dev, u_long cmd, caddr_t addr,
379			  int flag, struct thread *td)
380{
381	struct ctl_be_ramdisk_softc *softc;
382	int retval;
383
384	retval = 0;
385	softc = &rd_softc;
386
387	switch (cmd) {
388	case CTL_LUN_REQ: {
389		struct ctl_lun_req *lun_req;
390
391		lun_req = (struct ctl_lun_req *)addr;
392
393		switch (lun_req->reqtype) {
394		case CTL_LUNREQ_CREATE:
395			retval = ctl_backend_ramdisk_create(softc, lun_req,
396							    /*do_wait*/ 1);
397			break;
398		case CTL_LUNREQ_RM:
399			retval = ctl_backend_ramdisk_rm(softc, lun_req);
400			break;
401		case CTL_LUNREQ_MODIFY:
402			retval = ctl_backend_ramdisk_modify(softc, lun_req);
403			break;
404		default:
405			lun_req->status = CTL_LUN_ERROR;
406			snprintf(lun_req->error_str, sizeof(lun_req->error_str),
407				 "%s: invalid LUN request type %d", __func__,
408				 lun_req->reqtype);
409			break;
410		}
411		break;
412	}
413	default:
414		retval = ENOTTY;
415		break;
416	}
417
418	return (retval);
419}
420
421static int
422ctl_backend_ramdisk_rm(struct ctl_be_ramdisk_softc *softc,
423		       struct ctl_lun_req *req)
424{
425	struct ctl_be_ramdisk_lun *be_lun;
426	struct ctl_lun_rm_params *params;
427	int retval;
428
429
430	retval = 0;
431	params = &req->reqdata.rm;
432
433	be_lun = NULL;
434
435	mtx_lock(&softc->lock);
436
437	STAILQ_FOREACH(be_lun, &softc->lun_list, links) {
438		if (be_lun->ctl_be_lun.lun_id == params->lun_id)
439			break;
440	}
441	mtx_unlock(&softc->lock);
442
443	if (be_lun == NULL) {
444		snprintf(req->error_str, sizeof(req->error_str),
445			 "%s: LUN %u is not managed by the ramdisk backend",
446			 __func__, params->lun_id);
447		goto bailout_error;
448	}
449
450	retval = ctl_disable_lun(&be_lun->ctl_be_lun);
451
452	if (retval != 0) {
453		snprintf(req->error_str, sizeof(req->error_str),
454			 "%s: error %d returned from ctl_disable_lun() for "
455			 "LUN %d", __func__, retval, params->lun_id);
456		goto bailout_error;
457	}
458
459	/*
460	 * Set the waiting flag before we invalidate the LUN.  Our shutdown
461	 * routine can be called any time after we invalidate the LUN,
462	 * and can be called from our context.
463	 *
464	 * This tells the shutdown routine that we're waiting, or we're
465	 * going to wait for the shutdown to happen.
466	 */
467	mtx_lock(&softc->lock);
468	be_lun->flags |= CTL_BE_RAMDISK_LUN_WAITING;
469	mtx_unlock(&softc->lock);
470
471	retval = ctl_invalidate_lun(&be_lun->ctl_be_lun);
472	if (retval != 0) {
473		snprintf(req->error_str, sizeof(req->error_str),
474			 "%s: error %d returned from ctl_invalidate_lun() for "
475			 "LUN %d", __func__, retval, params->lun_id);
476		mtx_lock(&softc->lock);
477		be_lun->flags &= ~CTL_BE_RAMDISK_LUN_WAITING;
478		mtx_unlock(&softc->lock);
479		goto bailout_error;
480	}
481
482	mtx_lock(&softc->lock);
483
484	while ((be_lun->flags & CTL_BE_RAMDISK_LUN_UNCONFIGURED) == 0) {
485		retval = msleep(be_lun, &softc->lock, PCATCH, "ctlram", 0);
486 		if (retval == EINTR)
487			break;
488	}
489	be_lun->flags &= ~CTL_BE_RAMDISK_LUN_WAITING;
490
491	/*
492	 * We only remove this LUN from the list and free it (below) if
493	 * retval == 0.  If the user interrupted the wait, we just bail out
494	 * without actually freeing the LUN.  We let the shutdown routine
495	 * free the LUN if that happens.
496	 */
497	if (retval == 0) {
498		STAILQ_REMOVE(&softc->lun_list, be_lun, ctl_be_ramdisk_lun,
499			      links);
500		softc->num_luns--;
501	}
502
503	mtx_unlock(&softc->lock);
504
505	if (retval == 0) {
506		taskqueue_drain(be_lun->io_taskqueue, &be_lun->io_task);
507		taskqueue_free(be_lun->io_taskqueue);
508		ctl_free_opts(&be_lun->ctl_be_lun.options);
509		mtx_destroy(&be_lun->queue_lock);
510		free(be_lun, M_RAMDISK);
511	}
512
513	req->status = CTL_LUN_OK;
514
515	return (retval);
516
517bailout_error:
518	req->status = CTL_LUN_ERROR;
519
520	return (0);
521}
522
523static int
524ctl_backend_ramdisk_create(struct ctl_be_ramdisk_softc *softc,
525			   struct ctl_lun_req *req, int do_wait)
526{
527	struct ctl_be_ramdisk_lun *be_lun;
528	struct ctl_lun_create_params *params;
529	uint32_t blocksize;
530	char *value;
531	char tmpstr[32];
532	int retval, unmap;
533
534	retval = 0;
535	params = &req->reqdata.create;
536	if (params->blocksize_bytes != 0)
537		blocksize = params->blocksize_bytes;
538	else
539		blocksize = 512;
540
541	be_lun = malloc(sizeof(*be_lun), M_RAMDISK, M_ZERO | (do_wait ?
542			M_WAITOK : M_NOWAIT));
543
544	if (be_lun == NULL) {
545		snprintf(req->error_str, sizeof(req->error_str),
546			 "%s: error allocating %zd bytes", __func__,
547			 sizeof(*be_lun));
548		goto bailout_error;
549	}
550	sprintf(be_lun->lunname, "cram%d", softc->num_luns);
551	ctl_init_opts(&be_lun->ctl_be_lun.options,
552	    req->num_be_args, req->kern_be_args);
553
554	if (params->flags & CTL_LUN_FLAG_DEV_TYPE)
555		be_lun->ctl_be_lun.lun_type = params->device_type;
556	else
557		be_lun->ctl_be_lun.lun_type = T_DIRECT;
558
559	if (be_lun->ctl_be_lun.lun_type == T_DIRECT) {
560
561		if (params->lun_size_bytes < blocksize) {
562			snprintf(req->error_str, sizeof(req->error_str),
563				 "%s: LUN size %ju < blocksize %u", __func__,
564				 params->lun_size_bytes, blocksize);
565			goto bailout_error;
566		}
567
568		be_lun->size_blocks = params->lun_size_bytes / blocksize;
569		be_lun->size_bytes = be_lun->size_blocks * blocksize;
570
571		be_lun->ctl_be_lun.maxlba = be_lun->size_blocks - 1;
572		be_lun->ctl_be_lun.atomicblock = UINT32_MAX;
573		be_lun->ctl_be_lun.opttxferlen = softc->rd_size / blocksize;
574	} else {
575		be_lun->ctl_be_lun.maxlba = 0;
576		blocksize = 0;
577		be_lun->size_bytes = 0;
578		be_lun->size_blocks = 0;
579	}
580
581	be_lun->ctl_be_lun.blocksize = blocksize;
582
583	/* Tell the user the blocksize we ended up using */
584	params->blocksize_bytes = blocksize;
585
586	/* Tell the user the exact size we ended up using */
587	params->lun_size_bytes = be_lun->size_bytes;
588
589	be_lun->softc = softc;
590
591	unmap = 1;
592	value = ctl_get_opt(&be_lun->ctl_be_lun.options, "unmap");
593	if (value != NULL && strcmp(value, "on") == 0)
594		unmap = (strcmp(value, "on") == 0);
595
596	be_lun->flags = CTL_BE_RAMDISK_LUN_UNCONFIGURED;
597	be_lun->ctl_be_lun.flags = CTL_LUN_FLAG_PRIMARY;
598	if (unmap)
599		be_lun->ctl_be_lun.flags |= CTL_LUN_FLAG_UNMAP;
600	be_lun->ctl_be_lun.be_lun = be_lun;
601
602	if (params->flags & CTL_LUN_FLAG_ID_REQ) {
603		be_lun->ctl_be_lun.req_lun_id = params->req_lun_id;
604		be_lun->ctl_be_lun.flags |= CTL_LUN_FLAG_ID_REQ;
605	} else
606		be_lun->ctl_be_lun.req_lun_id = 0;
607
608	be_lun->ctl_be_lun.lun_shutdown = ctl_backend_ramdisk_lun_shutdown;
609	be_lun->ctl_be_lun.lun_config_status =
610		ctl_backend_ramdisk_lun_config_status;
611	be_lun->ctl_be_lun.be = &ctl_be_ramdisk_driver;
612	if ((params->flags & CTL_LUN_FLAG_SERIAL_NUM) == 0) {
613		snprintf(tmpstr, sizeof(tmpstr), "MYSERIAL%4d",
614			 softc->num_luns);
615		strncpy((char *)be_lun->ctl_be_lun.serial_num, tmpstr,
616			MIN(sizeof(be_lun->ctl_be_lun.serial_num),
617			    sizeof(tmpstr)));
618
619		/* Tell the user what we used for a serial number */
620		strncpy((char *)params->serial_num, tmpstr,
621			MIN(sizeof(params->serial_num), sizeof(tmpstr)));
622	} else {
623		strncpy((char *)be_lun->ctl_be_lun.serial_num,
624			params->serial_num,
625			MIN(sizeof(be_lun->ctl_be_lun.serial_num),
626			    sizeof(params->serial_num)));
627	}
628	if ((params->flags & CTL_LUN_FLAG_DEVID) == 0) {
629		snprintf(tmpstr, sizeof(tmpstr), "MYDEVID%4d", softc->num_luns);
630		strncpy((char *)be_lun->ctl_be_lun.device_id, tmpstr,
631			MIN(sizeof(be_lun->ctl_be_lun.device_id),
632			    sizeof(tmpstr)));
633
634		/* Tell the user what we used for a device ID */
635		strncpy((char *)params->device_id, tmpstr,
636			MIN(sizeof(params->device_id), sizeof(tmpstr)));
637	} else {
638		strncpy((char *)be_lun->ctl_be_lun.device_id,
639			params->device_id,
640			MIN(sizeof(be_lun->ctl_be_lun.device_id),
641			    sizeof(params->device_id)));
642	}
643
644	STAILQ_INIT(&be_lun->cont_queue);
645	mtx_init(&be_lun->queue_lock, "cram queue lock", NULL, MTX_DEF);
646	TASK_INIT(&be_lun->io_task, /*priority*/0, ctl_backend_ramdisk_worker,
647	    be_lun);
648
649	be_lun->io_taskqueue = taskqueue_create(be_lun->lunname, M_WAITOK,
650	    taskqueue_thread_enqueue, /*context*/&be_lun->io_taskqueue);
651	if (be_lun->io_taskqueue == NULL) {
652		snprintf(req->error_str, sizeof(req->error_str),
653			 "%s: Unable to create taskqueue", __func__);
654		goto bailout_error;
655	}
656
657	retval = taskqueue_start_threads(&be_lun->io_taskqueue,
658					 /*num threads*/1,
659					 /*priority*/PWAIT,
660					 /*thread name*/
661					 "%s taskq", be_lun->lunname);
662	if (retval != 0)
663		goto bailout_error;
664
665	mtx_lock(&softc->lock);
666	softc->num_luns++;
667	STAILQ_INSERT_TAIL(&softc->lun_list, be_lun, links);
668
669	mtx_unlock(&softc->lock);
670
671	retval = ctl_add_lun(&be_lun->ctl_be_lun);
672	if (retval != 0) {
673		mtx_lock(&softc->lock);
674		STAILQ_REMOVE(&softc->lun_list, be_lun, ctl_be_ramdisk_lun,
675			      links);
676		softc->num_luns--;
677		mtx_unlock(&softc->lock);
678		snprintf(req->error_str, sizeof(req->error_str),
679			 "%s: ctl_add_lun() returned error %d, see dmesg for "
680			"details", __func__, retval);
681		retval = 0;
682		goto bailout_error;
683	}
684
685	if (do_wait == 0)
686		return (retval);
687
688	mtx_lock(&softc->lock);
689
690	/*
691	 * Tell the config_status routine that we're waiting so it won't
692	 * clean up the LUN in the event of an error.
693	 */
694	be_lun->flags |= CTL_BE_RAMDISK_LUN_WAITING;
695
696	while (be_lun->flags & CTL_BE_RAMDISK_LUN_UNCONFIGURED) {
697		retval = msleep(be_lun, &softc->lock, PCATCH, "ctlram", 0);
698		if (retval == EINTR)
699			break;
700	}
701	be_lun->flags &= ~CTL_BE_RAMDISK_LUN_WAITING;
702
703	if (be_lun->flags & CTL_BE_RAMDISK_LUN_CONFIG_ERR) {
704		snprintf(req->error_str, sizeof(req->error_str),
705			 "%s: LUN configuration error, see dmesg for details",
706			 __func__);
707		STAILQ_REMOVE(&softc->lun_list, be_lun, ctl_be_ramdisk_lun,
708			      links);
709		softc->num_luns--;
710		mtx_unlock(&softc->lock);
711		goto bailout_error;
712	} else {
713		params->req_lun_id = be_lun->ctl_be_lun.lun_id;
714	}
715	mtx_unlock(&softc->lock);
716
717	req->status = CTL_LUN_OK;
718
719	return (retval);
720
721bailout_error:
722	req->status = CTL_LUN_ERROR;
723	if (be_lun != NULL) {
724		if (be_lun->io_taskqueue != NULL) {
725			taskqueue_free(be_lun->io_taskqueue);
726		}
727		ctl_free_opts(&be_lun->ctl_be_lun.options);
728		mtx_destroy(&be_lun->queue_lock);
729		free(be_lun, M_RAMDISK);
730	}
731
732	return (retval);
733}
734
735static int
736ctl_backend_ramdisk_modify(struct ctl_be_ramdisk_softc *softc,
737		       struct ctl_lun_req *req)
738{
739	struct ctl_be_ramdisk_lun *be_lun;
740	struct ctl_lun_modify_params *params;
741	uint32_t blocksize;
742
743	params = &req->reqdata.modify;
744
745	be_lun = NULL;
746
747	mtx_lock(&softc->lock);
748	STAILQ_FOREACH(be_lun, &softc->lun_list, links) {
749		if (be_lun->ctl_be_lun.lun_id == params->lun_id)
750			break;
751	}
752	mtx_unlock(&softc->lock);
753
754	if (be_lun == NULL) {
755		snprintf(req->error_str, sizeof(req->error_str),
756			 "%s: LUN %u is not managed by the ramdisk backend",
757			 __func__, params->lun_id);
758		goto bailout_error;
759	}
760
761	if (params->lun_size_bytes == 0) {
762		snprintf(req->error_str, sizeof(req->error_str),
763			"%s: LUN size \"auto\" not supported "
764			"by the ramdisk backend", __func__);
765		goto bailout_error;
766	}
767
768	blocksize = be_lun->ctl_be_lun.blocksize;
769
770	if (params->lun_size_bytes < blocksize) {
771		snprintf(req->error_str, sizeof(req->error_str),
772			"%s: LUN size %ju < blocksize %u", __func__,
773			params->lun_size_bytes, blocksize);
774		goto bailout_error;
775	}
776
777	be_lun->size_blocks = params->lun_size_bytes / blocksize;
778	be_lun->size_bytes = be_lun->size_blocks * blocksize;
779
780	/*
781	 * The maximum LBA is the size - 1.
782	 *
783	 * XXX: Note that this field is being updated without locking,
784	 * 	which might cause problems on 32-bit architectures.
785	 */
786	be_lun->ctl_be_lun.maxlba = be_lun->size_blocks - 1;
787	ctl_lun_capacity_changed(&be_lun->ctl_be_lun);
788
789	/* Tell the user the exact size we ended up using */
790	params->lun_size_bytes = be_lun->size_bytes;
791
792	req->status = CTL_LUN_OK;
793
794	return (0);
795
796bailout_error:
797	req->status = CTL_LUN_ERROR;
798
799	return (0);
800}
801
802static void
803ctl_backend_ramdisk_lun_shutdown(void *be_lun)
804{
805	struct ctl_be_ramdisk_lun *lun;
806	struct ctl_be_ramdisk_softc *softc;
807	int do_free;
808
809	lun = (struct ctl_be_ramdisk_lun *)be_lun;
810	softc = lun->softc;
811	do_free = 0;
812
813	mtx_lock(&softc->lock);
814
815	lun->flags |= CTL_BE_RAMDISK_LUN_UNCONFIGURED;
816
817	if (lun->flags & CTL_BE_RAMDISK_LUN_WAITING) {
818		wakeup(lun);
819	} else {
820		STAILQ_REMOVE(&softc->lun_list, lun, ctl_be_ramdisk_lun,
821			      links);
822		softc->num_luns--;
823		do_free = 1;
824	}
825
826	mtx_unlock(&softc->lock);
827
828	if (do_free != 0)
829		free(be_lun, M_RAMDISK);
830}
831
832static void
833ctl_backend_ramdisk_lun_config_status(void *be_lun,
834				      ctl_lun_config_status status)
835{
836	struct ctl_be_ramdisk_lun *lun;
837	struct ctl_be_ramdisk_softc *softc;
838
839	lun = (struct ctl_be_ramdisk_lun *)be_lun;
840	softc = lun->softc;
841
842	if (status == CTL_LUN_CONFIG_OK) {
843		mtx_lock(&softc->lock);
844		lun->flags &= ~CTL_BE_RAMDISK_LUN_UNCONFIGURED;
845		if (lun->flags & CTL_BE_RAMDISK_LUN_WAITING)
846			wakeup(lun);
847		mtx_unlock(&softc->lock);
848
849		/*
850		 * We successfully added the LUN, attempt to enable it.
851		 */
852		if (ctl_enable_lun(&lun->ctl_be_lun) != 0) {
853			printf("%s: ctl_enable_lun() failed!\n", __func__);
854			if (ctl_invalidate_lun(&lun->ctl_be_lun) != 0) {
855				printf("%s: ctl_invalidate_lun() failed!\n",
856				       __func__);
857			}
858		}
859
860		return;
861	}
862
863
864	mtx_lock(&softc->lock);
865	lun->flags &= ~CTL_BE_RAMDISK_LUN_UNCONFIGURED;
866
867	/*
868	 * If we have a user waiting, let him handle the cleanup.  If not,
869	 * clean things up here.
870	 */
871	if (lun->flags & CTL_BE_RAMDISK_LUN_WAITING) {
872		lun->flags |= CTL_BE_RAMDISK_LUN_CONFIG_ERR;
873		wakeup(lun);
874	} else {
875		STAILQ_REMOVE(&softc->lun_list, lun, ctl_be_ramdisk_lun,
876			      links);
877		softc->num_luns--;
878		free(lun, M_RAMDISK);
879	}
880	mtx_unlock(&softc->lock);
881}
882
883static int
884ctl_backend_ramdisk_config_write(union ctl_io *io)
885{
886	struct ctl_be_ramdisk_softc *softc;
887	int retval;
888
889	retval = 0;
890	softc = &rd_softc;
891
892	switch (io->scsiio.cdb[0]) {
893	case SYNCHRONIZE_CACHE:
894	case SYNCHRONIZE_CACHE_16:
895		/*
896		 * The upper level CTL code will filter out any CDBs with
897		 * the immediate bit set and return the proper error.  It
898		 * will also not allow a sync cache command to go to a LUN
899		 * that is powered down.
900		 *
901		 * We don't really need to worry about what LBA range the
902		 * user asked to be synced out.  When they issue a sync
903		 * cache command, we'll sync out the whole thing.
904		 *
905		 * This is obviously just a stubbed out implementation.
906		 * The real implementation will be in the RAIDCore/CTL
907		 * interface, and can only really happen when RAIDCore
908		 * implements a per-array cache sync.
909		 */
910		ctl_set_success(&io->scsiio);
911		ctl_config_write_done(io);
912		break;
913	case START_STOP_UNIT: {
914		struct scsi_start_stop_unit *cdb;
915		struct ctl_be_lun *ctl_be_lun;
916		struct ctl_be_ramdisk_lun *be_lun;
917
918		cdb = (struct scsi_start_stop_unit *)io->scsiio.cdb;
919
920		ctl_be_lun = (struct ctl_be_lun *)io->io_hdr.ctl_private[
921			CTL_PRIV_BACKEND_LUN].ptr;
922		be_lun = (struct ctl_be_ramdisk_lun *)ctl_be_lun->be_lun;
923
924		if (cdb->how & SSS_START)
925			retval = ctl_start_lun(ctl_be_lun);
926		else {
927			retval = ctl_stop_lun(ctl_be_lun);
928#ifdef NEEDTOPORT
929			if ((retval == 0)
930			 && (cdb->byte2 & SSS_ONOFFLINE))
931				retval = ctl_lun_offline(ctl_be_lun);
932#endif
933		}
934
935		/*
936		 * In general, the above routines should not fail.  They
937		 * just set state for the LUN.  So we've got something
938		 * pretty wrong here if we can't start or stop the LUN.
939		 */
940		if (retval != 0) {
941			ctl_set_internal_failure(&io->scsiio,
942						 /*sks_valid*/ 1,
943						 /*retry_count*/ 0xf051);
944			retval = CTL_RETVAL_COMPLETE;
945		} else {
946			ctl_set_success(&io->scsiio);
947		}
948		ctl_config_write_done(io);
949		break;
950	}
951	case WRITE_SAME_10:
952	case WRITE_SAME_16:
953	case UNMAP:
954		ctl_set_success(&io->scsiio);
955		ctl_config_write_done(io);
956		break;
957	default:
958		ctl_set_invalid_opcode(&io->scsiio);
959		ctl_config_write_done(io);
960		retval = CTL_RETVAL_COMPLETE;
961		break;
962	}
963
964	return (retval);
965}
966
967static int
968ctl_backend_ramdisk_config_read(union ctl_io *io)
969{
970	int retval = 0;
971
972	switch (io->scsiio.cdb[0]) {
973	case SERVICE_ACTION_IN:
974		if (io->scsiio.cdb[1] == SGLS_SERVICE_ACTION) {
975			/* We have nothing to tell, leave default data. */
976			ctl_config_read_done(io);
977			retval = CTL_RETVAL_COMPLETE;
978			break;
979		}
980		ctl_set_invalid_field(&io->scsiio,
981				      /*sks_valid*/ 1,
982				      /*command*/ 1,
983				      /*field*/ 1,
984				      /*bit_valid*/ 1,
985				      /*bit*/ 4);
986		ctl_config_read_done(io);
987		retval = CTL_RETVAL_COMPLETE;
988		break;
989	default:
990		ctl_set_invalid_opcode(&io->scsiio);
991		ctl_config_read_done(io);
992		retval = CTL_RETVAL_COMPLETE;
993		break;
994	}
995
996	return (retval);
997}
998