xref: /freebsd/sys/dev/nvme/nvme_sim.c (revision 58a0f0d00c0cc4a90ce584a61470290751bfcac7)
1 /*-
2  * Copyright (c) 2016 Netflix, Inc
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer,
9  *    without modification, immediately at the beginning of the file.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  */
25 
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
28 
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/buf.h>
32 #include <sys/bus.h>
33 #include <sys/conf.h>
34 #include <sys/ioccom.h>
35 #include <sys/malloc.h>
36 #include <sys/proc.h>
37 #include <sys/smp.h>
38 
39 #include <cam/cam.h>
40 #include <cam/cam_ccb.h>
41 #include <cam/cam_sim.h>
42 #include <cam/cam_xpt_sim.h>
43 #include <cam/cam_xpt_internal.h>	// Yes, this is wrong.
44 #include <cam/cam_debug.h>
45 
46 #include <dev/pci/pcivar.h>
47 #include <dev/pci/pcireg.h>
48 
49 #include "nvme_private.h"
50 
51 #define ccb_accb_ptr spriv_ptr0
52 #define ccb_ctrlr_ptr spriv_ptr1
53 static void	nvme_sim_action(struct cam_sim *sim, union ccb *ccb);
54 static void	nvme_sim_poll(struct cam_sim *sim);
55 
56 #define sim2softc(sim)	((struct nvme_sim_softc *)cam_sim_softc(sim))
57 #define sim2ns(sim)	(sim2softc(sim)->s_ns)
58 #define sim2ctrlr(sim)	(sim2softc(sim)->s_ctrlr)
59 
60 struct nvme_sim_softc
61 {
62 	struct nvme_controller	*s_ctrlr;
63 	struct nvme_namespace	*s_ns;
64 	struct cam_sim		*s_sim;
65 	struct cam_path		*s_path;
66 };
67 
68 static void
69 nvme_sim_nvmeio_done(void *ccb_arg, const struct nvme_completion *cpl)
70 {
71 	union ccb *ccb = (union ccb *)ccb_arg;
72 
73 	/*
74 	 * Let the periph know the completion, and let it sort out what
75 	 * it means. Make our best guess, though for the status code.
76 	 */
77 	memcpy(&ccb->nvmeio.cpl, cpl, sizeof(*cpl));
78 	ccb->ccb_h.status &= ~CAM_SIM_QUEUED;
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 	ccb->ccb_h.status |= CAM_SIM_QUEUED;
118 
119 	memcpy(&req->cmd, &ccb->nvmeio.cmd, sizeof(ccb->nvmeio.cmd));
120 
121 	if (ccb->ccb_h.func_code == XPT_NVME_IO)
122 		nvme_ctrlr_submit_io_request(ctrlr, req);
123 	else
124 		nvme_ctrlr_submit_admin_request(ctrlr, req);
125 }
126 
127 static uint32_t
128 nvme_link_kBps(struct nvme_controller *ctrlr)
129 {
130 	uint32_t speed, lanes, link[] = { 1, 250000, 500000, 985000, 1970000 };
131 	uint32_t status;
132 
133 	status = pcie_read_config(ctrlr->dev, PCIER_LINK_STA, 2);
134 	speed = status & PCIEM_LINK_STA_SPEED;
135 	lanes = (status & PCIEM_LINK_STA_WIDTH) >> 4;
136 	/*
137 	 * Failsafe on link speed indicator. If it is insane report the number of
138 	 * lanes as the speed. Not 100% accurate, but may be diagnostic.
139 	 */
140 	if (speed >= nitems(link))
141 		speed = 0;
142 	return link[speed] * lanes;
143 }
144 
145 static void
146 nvme_sim_action(struct cam_sim *sim, union ccb *ccb)
147 {
148 	struct nvme_controller *ctrlr;
149 	struct nvme_namespace *ns;
150 
151 	CAM_DEBUG(ccb->ccb_h.path, CAM_DEBUG_TRACE,
152 	    ("nvme_sim_action: func= %#x\n",
153 		ccb->ccb_h.func_code));
154 
155 	/*
156 	 * XXX when we support multiple namespaces in the base driver we'll need
157 	 * to revisit how all this gets stored and saved in the periph driver's
158 	 * reserved areas. Right now we store all three in the softc of the sim.
159 	 */
160 	ns = sim2ns(sim);
161 	ctrlr = sim2ctrlr(sim);
162 
163 	mtx_assert(&ctrlr->lock, MA_OWNED);
164 
165 	switch (ccb->ccb_h.func_code) {
166 	case XPT_CALC_GEOMETRY:		/* Calculate Geometry Totally nuts ? XXX */
167 		/*
168 		 * Only meaningful for old-school SCSI disks since only the SCSI
169 		 * da driver generates them. Reject all these that slip through.
170 		 */
171 		/*FALLTHROUGH*/
172 	case XPT_ABORT:			/* Abort the specified CCB */
173 		ccb->ccb_h.status = CAM_REQ_INVALID;
174 		break;
175 	case XPT_SET_TRAN_SETTINGS:
176 		/*
177 		 * NVMe doesn't really have different transfer settings, but
178 		 * other parts of CAM think failure here is a big deal.
179 		 */
180 		ccb->ccb_h.status = CAM_REQ_CMP;
181 		break;
182 	case XPT_PATH_INQ:		/* Path routing inquiry */
183 	{
184 		struct ccb_pathinq	*cpi = &ccb->cpi;
185 		device_t		dev = ctrlr->dev;
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->xport_specific.nvme.domain = pci_get_domain(dev);
214 		cpi->xport_specific.nvme.bus = pci_get_bus(dev);
215 		cpi->xport_specific.nvme.slot = pci_get_slot(dev);
216 		cpi->xport_specific.nvme.function = pci_get_function(dev);
217 		cpi->xport_specific.nvme.extra = 0;
218 		cpi->ccb_h.status = CAM_REQ_CMP;
219 		break;
220 	}
221 	case XPT_GET_TRAN_SETTINGS:	/* Get transport settings */
222 	{
223 		struct ccb_trans_settings	*cts;
224 		struct ccb_trans_settings_nvme	*nvmep;
225 		struct ccb_trans_settings_nvme	*nvmex;
226 		device_t dev;
227 		uint32_t status, caps;
228 
229 		dev = ctrlr->dev;
230 		cts = &ccb->cts;
231 		nvmex = &cts->xport_specific.nvme;
232 		nvmep = &cts->proto_specific.nvme;
233 
234 		status = pcie_read_config(dev, PCIER_LINK_STA, 2);
235 		caps = pcie_read_config(dev, PCIER_LINK_CAP, 2);
236 		nvmex->valid = CTS_NVME_VALID_SPEC | CTS_NVME_VALID_LINK;
237 		nvmex->spec = nvme_mmio_read_4(ctrlr, vs);
238 		nvmex->speed = status & PCIEM_LINK_STA_SPEED;
239 		nvmex->lanes = (status & PCIEM_LINK_STA_WIDTH) >> 4;
240 		nvmex->max_speed = caps & PCIEM_LINK_CAP_MAX_SPEED;
241 		nvmex->max_lanes = (caps & PCIEM_LINK_CAP_MAX_WIDTH) >> 4;
242 
243 		/* XXX these should be something else maybe ? */
244 		nvmep->valid = 1;
245 		nvmep->spec = nvmex->spec;
246 
247 		cts->transport = XPORT_NVME;
248 		cts->protocol = PROTO_NVME;
249 		cts->ccb_h.status = CAM_REQ_CMP;
250 		break;
251 	}
252 	case XPT_TERM_IO:		/* Terminate the I/O process */
253 		/*
254 		 * every driver handles this, but nothing generates it. Assume
255 		 * it's OK to just say 'that worked'.
256 		 */
257 		/*FALLTHROUGH*/
258 	case XPT_RESET_DEV:		/* Bus Device Reset the specified device */
259 	case XPT_RESET_BUS:		/* Reset the specified bus */
260 		/*
261 		 * NVMe doesn't really support physically resetting the bus. It's part
262 		 * of the bus scanning dance, so return sucess to tell the process to
263 		 * proceed.
264 		 */
265 		ccb->ccb_h.status = CAM_REQ_CMP;
266 		break;
267 	case XPT_NVME_IO:		/* Execute the requested I/O operation */
268 	case XPT_NVME_ADMIN:		/* or Admin operation */
269 		nvme_sim_nvmeio(sim, ccb);
270 		return;			/* no done */
271 	default:
272 		ccb->ccb_h.status = CAM_REQ_INVALID;
273 		break;
274 	}
275 	xpt_done(ccb);
276 }
277 
278 static void
279 nvme_sim_poll(struct cam_sim *sim)
280 {
281 
282 	nvme_ctrlr_poll(sim2ctrlr(sim));
283 }
284 
285 static void *
286 nvme_sim_new_controller(struct nvme_controller *ctrlr)
287 {
288 	struct cam_devq *devq;
289 	int max_trans;
290 	int unit;
291 	struct nvme_sim_softc *sc = NULL;
292 
293 	max_trans = ctrlr->max_hw_pend_io;
294 	unit = device_get_unit(ctrlr->dev);
295 	devq = cam_simq_alloc(max_trans);
296 	if (devq == NULL)
297 		return NULL;
298 
299 	sc = malloc(sizeof(*sc), M_NVME, M_ZERO | M_WAITOK);
300 
301 	sc->s_ctrlr = ctrlr;
302 
303 	sc->s_sim = cam_sim_alloc(nvme_sim_action, nvme_sim_poll,
304 	    "nvme", sc, unit, &ctrlr->lock, max_trans, max_trans, devq);
305 	if (sc->s_sim == NULL) {
306 		printf("Failed to allocate a sim\n");
307 		cam_simq_free(devq);
308 		free(sc, M_NVME);
309 		return NULL;
310 	}
311 
312 	return sc;
313 }
314 
315 static void
316 nvme_sim_rescan_target(struct nvme_controller *ctrlr, struct cam_path *path)
317 {
318 	union ccb *ccb;
319 
320 	ccb = xpt_alloc_ccb_nowait();
321 	if (ccb == NULL) {
322 		printf("unable to alloc CCB for rescan\n");
323 		return;
324 	}
325 
326 	if (xpt_clone_path(&ccb->ccb_h.path, path) != CAM_REQ_CMP) {
327 		printf("unable to copy path for rescan\n");
328 		xpt_free_ccb(ccb);
329 		return;
330 	}
331 
332 	xpt_rescan(ccb);
333 }
334 
335 static void *
336 nvme_sim_new_ns(struct nvme_namespace *ns, void *sc_arg)
337 {
338 	struct nvme_sim_softc *sc = sc_arg;
339 	struct nvme_controller *ctrlr = sc->s_ctrlr;
340 	int i;
341 
342 	sc->s_ns = ns;
343 
344 	/*
345 	 * XXX this is creating one bus per ns, but it should be one
346 	 * XXX target per controller, and one LUN per namespace.
347 	 * XXX Current drives only support one NS, so there's time
348 	 * XXX to fix it later when new drives arrive.
349 	 *
350 	 * XXX I'm pretty sure the xpt_bus_register() call below is
351 	 * XXX like super lame and it really belongs in the sim_new_ctrlr
352 	 * XXX callback. Then the create_path below would be pretty close
353 	 * XXX to being right. Except we should be per-ns not per-ctrlr
354 	 * XXX data.
355 	 */
356 
357 	mtx_lock(&ctrlr->lock);
358 /* Create bus */
359 
360 	/*
361 	 * XXX do I need to lock ctrlr->lock ?
362 	 * XXX do I need to lock the path?
363 	 * ata and scsi seem to in their code, but their discovery is
364 	 * somewhat more asynchronous. We're only every called one at a
365 	 * time, and nothing is in parallel.
366 	 */
367 
368 	i = 0;
369 	if (xpt_bus_register(sc->s_sim, ctrlr->dev, 0) != CAM_SUCCESS)
370 		goto error;
371 	i++;
372 	if (xpt_create_path(&sc->s_path, /*periph*/NULL, cam_sim_path(sc->s_sim),
373 	    1, ns->id) != CAM_REQ_CMP)
374 		goto error;
375 	i++;
376 
377 	sc->s_path->device->nvme_data = nvme_ns_get_data(ns);
378 	sc->s_path->device->nvme_cdata = nvme_ctrlr_get_data(ns->ctrlr);
379 
380 /* Scan bus */
381 	nvme_sim_rescan_target(ctrlr, sc->s_path);
382 
383 	mtx_unlock(&ctrlr->lock);
384 
385 	return ns;
386 
387 error:
388 	switch (i) {
389 	case 2:
390 		xpt_free_path(sc->s_path);
391 	case 1:
392 		xpt_bus_deregister(cam_sim_path(sc->s_sim));
393 	case 0:
394 		cam_sim_free(sc->s_sim, /*free_devq*/TRUE);
395 	}
396 	mtx_unlock(&ctrlr->lock);
397 	return NULL;
398 }
399 
400 static void
401 nvme_sim_controller_fail(void *ctrlr_arg)
402 {
403 	/* XXX cleanup XXX */
404 }
405 
406 struct nvme_consumer *consumer_cookie;
407 
408 static void
409 nvme_sim_init(void)
410 {
411 	if (nvme_use_nvd)
412 		return;
413 
414 	consumer_cookie = nvme_register_consumer(nvme_sim_new_ns,
415 	    nvme_sim_new_controller, NULL, nvme_sim_controller_fail);
416 }
417 
418 SYSINIT(nvme_sim_register, SI_SUB_DRIVERS, SI_ORDER_ANY,
419     nvme_sim_init, NULL);
420 
421 static void
422 nvme_sim_uninit(void)
423 {
424 	if (nvme_use_nvd)
425 		return;
426 	/* XXX Cleanup */
427 
428 	nvme_unregister_consumer(consumer_cookie);
429 }
430 
431 SYSUNINIT(nvme_sim_unregister, SI_SUB_DRIVERS, SI_ORDER_ANY,
432     nvme_sim_uninit, NULL);
433