xref: /freebsd/sys/dev/nvme/nvme_sim.c (revision 5e53a4f90f82c4345f277dd87cc9292f26e04a29)
1 /*-
2  * Copyright (c) 2016 Netflix, Inc
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer,
10  *    without modification, immediately at the beginning of the file.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/buf.h>
33 #include <sys/bus.h>
34 #include <sys/conf.h>
35 #include <sys/ioccom.h>
36 #include <sys/malloc.h>
37 #include <sys/proc.h>
38 #include <sys/smp.h>
39 
40 #include <cam/cam.h>
41 #include <cam/cam_ccb.h>
42 #include <cam/cam_sim.h>
43 #include <cam/cam_xpt_sim.h>
44 #include <cam/cam_xpt_internal.h>	// Yes, this is wrong.
45 #include <cam/cam_debug.h>
46 
47 #include <dev/pci/pcivar.h>
48 #include <dev/pci/pcireg.h>
49 
50 #include "nvme_private.h"
51 
52 #define ccb_accb_ptr spriv_ptr0
53 #define ccb_ctrlr_ptr spriv_ptr1
54 static void	nvme_sim_action(struct cam_sim *sim, union ccb *ccb);
55 static void	nvme_sim_poll(struct cam_sim *sim);
56 
57 #define sim2softc(sim)	((struct nvme_sim_softc *)cam_sim_softc(sim))
58 #define sim2ns(sim)	(sim2softc(sim)->s_ns)
59 #define sim2ctrlr(sim)	(sim2softc(sim)->s_ctrlr)
60 
61 struct nvme_sim_softc
62 {
63 	struct nvme_controller	*s_ctrlr;
64 	struct nvme_namespace	*s_ns;
65 	struct cam_sim		*s_sim;
66 	struct cam_path		*s_path;
67 };
68 
69 static void
70 nvme_sim_nvmeio_done(void *ccb_arg, const struct nvme_completion *cpl)
71 {
72 	union ccb *ccb = (union ccb *)ccb_arg;
73 
74 	/*
75 	 * Let the periph know the completion, and let it sort out what
76 	 * it means. Make our best guess, though for the status code.
77 	 */
78 	memcpy(&ccb->nvmeio.cpl, cpl, sizeof(*cpl));
79 	if (nvme_completion_is_error(cpl)) {
80 		ccb->ccb_h.status = CAM_REQ_CMP_ERR;
81 		xpt_done(ccb);
82 	} else {
83 		ccb->ccb_h.status = CAM_REQ_CMP;
84 		xpt_done_direct(ccb);
85 	}
86 }
87 
88 static void
89 nvme_sim_nvmeio(struct cam_sim *sim, union ccb *ccb)
90 {
91 	struct ccb_nvmeio	*nvmeio = &ccb->nvmeio;
92 	struct nvme_request	*req;
93 	void			*payload;
94 	uint32_t		size;
95 	struct nvme_controller *ctrlr;
96 
97 	ctrlr = sim2ctrlr(sim);
98 	payload = nvmeio->data_ptr;
99 	size = nvmeio->dxfer_len;
100 	/* SG LIST ??? */
101 	if ((nvmeio->ccb_h.flags & CAM_DATA_MASK) == CAM_DATA_BIO)
102 		req = nvme_allocate_request_bio((struct bio *)payload,
103 		    nvme_sim_nvmeio_done, ccb);
104 	else if ((nvmeio->ccb_h.flags & CAM_DATA_SG) == CAM_DATA_SG)
105 		req = nvme_allocate_request_ccb(ccb, nvme_sim_nvmeio_done, ccb);
106 	else if (payload == NULL)
107 		req = nvme_allocate_request_null(nvme_sim_nvmeio_done, ccb);
108 	else
109 		req = nvme_allocate_request_vaddr(payload, size,
110 		    nvme_sim_nvmeio_done, ccb);
111 
112 	if (req == NULL) {
113 		nvmeio->ccb_h.status = CAM_RESRC_UNAVAIL;
114 		xpt_done(ccb);
115 		return;
116 	}
117 
118 	memcpy(&req->cmd, &ccb->nvmeio.cmd, sizeof(ccb->nvmeio.cmd));
119 
120 	if (ccb->ccb_h.func_code == XPT_NVME_IO)
121 		nvme_ctrlr_submit_io_request(ctrlr, req);
122 	else
123 		nvme_ctrlr_submit_admin_request(ctrlr, req);
124 
125 	ccb->ccb_h.status |= CAM_SIM_QUEUED;
126 }
127 
128 static uint32_t
129 nvme_link_kBps(struct nvme_controller *ctrlr)
130 {
131 	uint32_t speed, lanes, link[] = { 1, 250000, 500000, 985000, 1970000 };
132 	uint32_t status;
133 
134 	status = pcie_read_config(ctrlr->dev, PCIER_LINK_STA, 2);
135 	speed = status & PCIEM_LINK_STA_SPEED;
136 	lanes = (status & PCIEM_LINK_STA_WIDTH) >> 4;
137 	/*
138 	 * Failsafe on link speed indicator. If it is insane report the number of
139 	 * lanes as the speed. Not 100% accurate, but may be diagnostic.
140 	 */
141 	if (speed >= nitems(link))
142 		speed = 0;
143 	return link[speed] * lanes;
144 }
145 
146 static void
147 nvme_sim_action(struct cam_sim *sim, union ccb *ccb)
148 {
149 	struct nvme_controller *ctrlr;
150 	struct nvme_namespace *ns;
151 
152 	CAM_DEBUG(ccb->ccb_h.path, CAM_DEBUG_TRACE,
153 	    ("nvme_sim_action: func= %#x\n",
154 		ccb->ccb_h.func_code));
155 
156 	/*
157 	 * XXX when we support multiple namespaces in the base driver we'll need
158 	 * to revisit how all this gets stored and saved in the periph driver's
159 	 * reserved areas. Right now we store all three in the softc of the sim.
160 	 */
161 	ns = sim2ns(sim);
162 	ctrlr = sim2ctrlr(sim);
163 
164 	mtx_assert(&ctrlr->lock, MA_OWNED);
165 
166 	switch (ccb->ccb_h.func_code) {
167 	case XPT_CALC_GEOMETRY:		/* Calculate Geometry Totally nuts ? XXX */
168 		/*
169 		 * Only meaningful for old-school SCSI disks since only the SCSI
170 		 * da driver generates them. Reject all these that slip through.
171 		 */
172 		/*FALLTHROUGH*/
173 	case XPT_ABORT:			/* Abort the specified CCB */
174 		ccb->ccb_h.status = CAM_REQ_INVALID;
175 		break;
176 	case XPT_SET_TRAN_SETTINGS:
177 		/*
178 		 * NVMe doesn't really have different transfer settings, but
179 		 * other parts of CAM think failure here is a big deal.
180 		 */
181 		ccb->ccb_h.status = CAM_REQ_CMP;
182 		break;
183 	case XPT_PATH_INQ:		/* Path routing inquiry */
184 	{
185 		struct ccb_pathinq *cpi = &ccb->cpi;
186 
187 		/*
188 		 * NVMe may have multiple LUNs on the same path. Current generation
189 		 * of NVMe devives support only a single name space. Multiple name
190 		 * space drives are coming, but it's unclear how we should report
191 		 * them up the stack.
192 		 */
193 		cpi->version_num = 1;
194 		cpi->hba_inquiry = 0;
195 		cpi->target_sprt = 0;
196 		cpi->hba_misc =  PIM_UNMAPPED /* | PIM_NOSCAN */;
197 		cpi->hba_eng_cnt = 0;
198 		cpi->max_target = 0;
199 		cpi->max_lun = ctrlr->cdata.nn;
200 		cpi->maxio = nvme_ns_get_max_io_xfer_size(ns);
201 		cpi->initiator_id = 0;
202 		cpi->bus_id = cam_sim_bus(sim);
203 		cpi->base_transfer_speed = nvme_link_kBps(ctrlr);
204 		strlcpy(cpi->sim_vid, "FreeBSD", SIM_IDLEN);
205 		strlcpy(cpi->hba_vid, "NVMe", HBA_IDLEN);
206 		strlcpy(cpi->dev_name, cam_sim_name(sim), DEV_IDLEN);
207 		cpi->unit_number = cam_sim_unit(sim);
208 		cpi->transport = XPORT_NVME;		/* XXX XPORT_PCIE ? */
209 		cpi->transport_version = nvme_mmio_read_4(ctrlr, vs);
210 		cpi->protocol = PROTO_NVME;
211 		cpi->protocol_version = nvme_mmio_read_4(ctrlr, vs);
212 		cpi->xport_specific.nvme.nsid = ns->id;
213 		cpi->ccb_h.status = CAM_REQ_CMP;
214 		break;
215 	}
216 	case XPT_GET_TRAN_SETTINGS:	/* Get transport settings */
217 	{
218 		struct ccb_trans_settings	*cts;
219 		struct ccb_trans_settings_nvme	*nvmep;
220 		struct ccb_trans_settings_nvme	*nvmex;
221 		device_t dev;
222 		uint32_t status, caps;
223 
224 		dev = ctrlr->dev;
225 		cts = &ccb->cts;
226 		nvmex = &cts->xport_specific.nvme;
227 		nvmep = &cts->proto_specific.nvme;
228 
229 		status = pcie_read_config(dev, PCIER_LINK_STA, 2);
230 		caps = pcie_read_config(dev, PCIER_LINK_CAP, 2);
231 		nvmex->valid = CTS_NVME_VALID_SPEC | CTS_NVME_VALID_LINK;
232 		nvmex->spec = nvme_mmio_read_4(ctrlr, vs);
233 		nvmex->speed = status & PCIEM_LINK_STA_SPEED;
234 		nvmex->lanes = (status & PCIEM_LINK_STA_WIDTH) >> 4;
235 		nvmex->max_speed = caps & PCIEM_LINK_CAP_MAX_SPEED;
236 		nvmex->max_lanes = (caps & PCIEM_LINK_CAP_MAX_WIDTH) >> 4;
237 
238 		/* XXX these should be something else maybe ? */
239 		nvmep->valid = 1;
240 		nvmep->spec = nvmex->spec;
241 
242 		cts->transport = XPORT_NVME;
243 		cts->protocol = PROTO_NVME;
244 		cts->ccb_h.status = CAM_REQ_CMP;
245 		break;
246 	}
247 	case XPT_TERM_IO:		/* Terminate the I/O process */
248 		/*
249 		 * every driver handles this, but nothing generates it. Assume
250 		 * it's OK to just say 'that worked'.
251 		 */
252 		/*FALLTHROUGH*/
253 	case XPT_RESET_DEV:		/* Bus Device Reset the specified device */
254 	case XPT_RESET_BUS:		/* Reset the specified bus */
255 		/*
256 		 * NVMe doesn't really support physically resetting the bus. It's part
257 		 * of the bus scanning dance, so return sucess to tell the process to
258 		 * proceed.
259 		 */
260 		ccb->ccb_h.status = CAM_REQ_CMP;
261 		break;
262 	case XPT_NVME_IO:		/* Execute the requested I/O operation */
263 	case XPT_NVME_ADMIN:		/* or Admin operation */
264 		nvme_sim_nvmeio(sim, ccb);
265 		return;			/* no done */
266 	default:
267 		ccb->ccb_h.status = CAM_REQ_INVALID;
268 		break;
269 	}
270 	xpt_done(ccb);
271 }
272 
273 static void
274 nvme_sim_poll(struct cam_sim *sim)
275 {
276 
277 	nvme_ctrlr_poll(sim2ctrlr(sim));
278 }
279 
280 static void *
281 nvme_sim_new_controller(struct nvme_controller *ctrlr)
282 {
283 	struct cam_devq *devq;
284 	int max_trans;
285 	int unit;
286 	struct nvme_sim_softc *sc = NULL;
287 
288 	max_trans = ctrlr->max_hw_pend_io;
289 	unit = device_get_unit(ctrlr->dev);
290 	devq = cam_simq_alloc(max_trans);
291 	if (devq == NULL)
292 		return NULL;
293 
294 	sc = malloc(sizeof(*sc), M_NVME, M_ZERO | M_WAITOK);
295 
296 	sc->s_ctrlr = ctrlr;
297 
298 	sc->s_sim = cam_sim_alloc(nvme_sim_action, nvme_sim_poll,
299 	    "nvme", sc, unit, &ctrlr->lock, max_trans, max_trans, devq);
300 	if (sc->s_sim == NULL) {
301 		printf("Failed to allocate a sim\n");
302 		cam_simq_free(devq);
303 		free(sc, M_NVME);
304 		return NULL;
305 	}
306 
307 	return sc;
308 }
309 
310 static void
311 nvme_sim_rescan_target(struct nvme_controller *ctrlr, struct cam_path *path)
312 {
313 	union ccb *ccb;
314 
315 	ccb = xpt_alloc_ccb_nowait();
316 	if (ccb == NULL) {
317 		printf("unable to alloc CCB for rescan\n");
318 		return;
319 	}
320 
321 	if (xpt_clone_path(&ccb->ccb_h.path, path) != CAM_REQ_CMP) {
322 		printf("unable to copy path for rescan\n");
323 		xpt_free_ccb(ccb);
324 		return;
325 	}
326 
327 	xpt_rescan(ccb);
328 }
329 
330 static void *
331 nvme_sim_new_ns(struct nvme_namespace *ns, void *sc_arg)
332 {
333 	struct nvme_sim_softc *sc = sc_arg;
334 	struct nvme_controller *ctrlr = sc->s_ctrlr;
335 	int i;
336 
337 	sc->s_ns = ns;
338 
339 	/*
340 	 * XXX this is creating one bus per ns, but it should be one
341 	 * XXX target per controller, and one LUN per namespace.
342 	 * XXX Current drives only support one NS, so there's time
343 	 * XXX to fix it later when new drives arrive.
344 	 *
345 	 * XXX I'm pretty sure the xpt_bus_register() call below is
346 	 * XXX like super lame and it really belongs in the sim_new_ctrlr
347 	 * XXX callback. Then the create_path below would be pretty close
348 	 * XXX to being right. Except we should be per-ns not per-ctrlr
349 	 * XXX data.
350 	 */
351 
352 	mtx_lock(&ctrlr->lock);
353 /* Create bus */
354 
355 	/*
356 	 * XXX do I need to lock ctrlr->lock ?
357 	 * XXX do I need to lock the path?
358 	 * ata and scsi seem to in their code, but their discovery is
359 	 * somewhat more asynchronous. We're only every called one at a
360 	 * time, and nothing is in parallel.
361 	 */
362 
363 	i = 0;
364 	if (xpt_bus_register(sc->s_sim, ctrlr->dev, 0) != CAM_SUCCESS)
365 		goto error;
366 	i++;
367 	if (xpt_create_path(&sc->s_path, /*periph*/NULL, cam_sim_path(sc->s_sim),
368 	    1, ns->id) != CAM_REQ_CMP)
369 		goto error;
370 	i++;
371 
372 	sc->s_path->device->nvme_data = nvme_ns_get_data(ns);
373 	sc->s_path->device->nvme_cdata = nvme_ctrlr_get_data(ns->ctrlr);
374 
375 /* Scan bus */
376 	nvme_sim_rescan_target(ctrlr, sc->s_path);
377 
378 	mtx_unlock(&ctrlr->lock);
379 
380 	return ns;
381 
382 error:
383 	switch (i) {
384 	case 2:
385 		xpt_free_path(sc->s_path);
386 	case 1:
387 		xpt_bus_deregister(cam_sim_path(sc->s_sim));
388 	case 0:
389 		cam_sim_free(sc->s_sim, /*free_devq*/TRUE);
390 	}
391 	mtx_unlock(&ctrlr->lock);
392 	return NULL;
393 }
394 
395 static void
396 nvme_sim_controller_fail(void *ctrlr_arg)
397 {
398 	/* XXX cleanup XXX */
399 }
400 
401 struct nvme_consumer *consumer_cookie;
402 
403 static void
404 nvme_sim_init(void)
405 {
406 	if (nvme_use_nvd)
407 		return;
408 
409 	consumer_cookie = nvme_register_consumer(nvme_sim_new_ns,
410 	    nvme_sim_new_controller, NULL, nvme_sim_controller_fail);
411 }
412 
413 SYSINIT(nvme_sim_register, SI_SUB_DRIVERS, SI_ORDER_ANY,
414     nvme_sim_init, NULL);
415 
416 static void
417 nvme_sim_uninit(void)
418 {
419 	if (nvme_use_nvd)
420 		return;
421 	/* XXX Cleanup */
422 
423 	nvme_unregister_consumer(consumer_cookie);
424 }
425 
426 SYSUNINIT(nvme_sim_unregister, SI_SUB_DRIVERS, SI_ORDER_ANY,
427     nvme_sim_uninit, NULL);
428