xref: /freebsd/usr.sbin/bhyve/pci_virtio_9p.c (revision 98d920d9)
1 /*-
2  * Copyright (c) 2015 iXsystems Inc.
3  * Copyright (c) 2017-2018 Jakub Klama <jceel@FreeBSD.org>
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer
11  *    in this position and unchanged.
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 AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 /*
30  * VirtIO filesystem passthrough using 9p protocol.
31  */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include <sys/param.h>
37 #include <sys/linker_set.h>
38 #include <sys/uio.h>
39 #include <sys/capsicum.h>
40 
41 #include <errno.h>
42 #include <fcntl.h>
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <string.h>
46 #include <unistd.h>
47 #include <assert.h>
48 #include <pthread.h>
49 
50 #include <lib9p.h>
51 #include <backend/fs.h>
52 
53 #include "bhyverun.h"
54 #include "config.h"
55 #include "debug.h"
56 #include "pci_emul.h"
57 #include "virtio.h"
58 
59 #define	VT9P_MAX_IOV	128
60 #define VT9P_RINGSZ	256
61 #define	VT9P_MAXTAGSZ	256
62 #define	VT9P_CONFIGSPACESZ	(VT9P_MAXTAGSZ + sizeof(uint16_t))
63 
64 static int pci_vt9p_debug;
65 #define DPRINTF(params) if (pci_vt9p_debug) printf params
66 #define WPRINTF(params) printf params
67 
68 /*
69  * Per-device softc
70  */
71 struct pci_vt9p_softc {
72 	struct virtio_softc      vsc_vs;
73 	struct vqueue_info       vsc_vq;
74 	pthread_mutex_t          vsc_mtx;
75 	uint64_t                 vsc_cfg;
76 	uint64_t                 vsc_features;
77 	char *                   vsc_rootpath;
78 	struct pci_vt9p_config * vsc_config;
79 	struct l9p_backend *     vsc_fs_backend;
80 	struct l9p_server *      vsc_server;
81         struct l9p_connection *  vsc_conn;
82 };
83 
84 struct pci_vt9p_request {
85 	struct pci_vt9p_softc *	vsr_sc;
86 	struct iovec *		vsr_iov;
87 	size_t			vsr_niov;
88 	size_t			vsr_respidx;
89 	size_t			vsr_iolen;
90 	uint16_t		vsr_idx;
91 };
92 
93 struct pci_vt9p_config {
94 	uint16_t tag_len;
95 	char tag[0];
96 } __attribute__((packed));
97 
98 static int pci_vt9p_send(struct l9p_request *, const struct iovec *,
99     const size_t, const size_t, void *);
100 static void pci_vt9p_drop(struct l9p_request *, const struct iovec *, size_t,
101     void *);
102 static void pci_vt9p_reset(void *);
103 static void pci_vt9p_notify(void *, struct vqueue_info *);
104 static int pci_vt9p_cfgread(void *, int, int, uint32_t *);
105 static void pci_vt9p_neg_features(void *, uint64_t);
106 
107 static struct virtio_consts vt9p_vi_consts = {
108 	.vc_name =	"vt9p",
109 	.vc_nvq =	1,
110 	.vc_cfgsize =	VT9P_CONFIGSPACESZ,
111 	.vc_reset =	pci_vt9p_reset,
112 	.vc_qnotify =	pci_vt9p_notify,
113 	.vc_cfgread =	pci_vt9p_cfgread,
114 	.vc_apply_features = pci_vt9p_neg_features,
115 	.vc_hv_caps =	(1 << 0),
116 };
117 
118 static void
119 pci_vt9p_reset(void *vsc)
120 {
121 	struct pci_vt9p_softc *sc;
122 
123 	sc = vsc;
124 
125 	DPRINTF(("vt9p: device reset requested !\n"));
126 	vi_reset_dev(&sc->vsc_vs);
127 }
128 
129 static void
130 pci_vt9p_neg_features(void *vsc, uint64_t negotiated_features)
131 {
132 	struct pci_vt9p_softc *sc = vsc;
133 
134 	sc->vsc_features = negotiated_features;
135 }
136 
137 static int
138 pci_vt9p_cfgread(void *vsc, int offset, int size, uint32_t *retval)
139 {
140 	struct pci_vt9p_softc *sc = vsc;
141 	void *ptr;
142 
143 	ptr = (uint8_t *)sc->vsc_config + offset;
144 	memcpy(retval, ptr, size);
145 	return (0);
146 }
147 
148 static int
149 pci_vt9p_get_buffer(struct l9p_request *req, struct iovec *iov, size_t *niov,
150     void *arg __unused)
151 {
152 	struct pci_vt9p_request *preq = req->lr_aux;
153 	size_t n = preq->vsr_niov - preq->vsr_respidx;
154 
155 	memcpy(iov, preq->vsr_iov + preq->vsr_respidx,
156 	    n * sizeof(struct iovec));
157 	*niov = n;
158 	return (0);
159 }
160 
161 static int
162 pci_vt9p_send(struct l9p_request *req, const struct iovec *iov __unused,
163     const size_t niov __unused, const size_t iolen, void *arg __unused)
164 {
165 	struct pci_vt9p_request *preq = req->lr_aux;
166 	struct pci_vt9p_softc *sc = preq->vsr_sc;
167 
168 	preq->vsr_iolen = iolen;
169 
170 	pthread_mutex_lock(&sc->vsc_mtx);
171 	vq_relchain(&sc->vsc_vq, preq->vsr_idx, preq->vsr_iolen);
172 	vq_endchains(&sc->vsc_vq, 1);
173 	pthread_mutex_unlock(&sc->vsc_mtx);
174 	free(preq);
175 	return (0);
176 }
177 
178 static void
179 pci_vt9p_drop(struct l9p_request *req, const struct iovec *iov __unused,
180     size_t niov __unused, void *arg __unused)
181 {
182 	struct pci_vt9p_request *preq = req->lr_aux;
183 	struct pci_vt9p_softc *sc = preq->vsr_sc;
184 
185 	pthread_mutex_lock(&sc->vsc_mtx);
186 	vq_relchain(&sc->vsc_vq, preq->vsr_idx, 0);
187 	vq_endchains(&sc->vsc_vq, 1);
188 	pthread_mutex_unlock(&sc->vsc_mtx);
189 	free(preq);
190 }
191 
192 static void
193 pci_vt9p_notify(void *vsc, struct vqueue_info *vq)
194 {
195 	struct iovec iov[VT9P_MAX_IOV];
196 	struct pci_vt9p_softc *sc;
197 	struct pci_vt9p_request *preq;
198 	struct vi_req req;
199 	int n;
200 
201 	sc = vsc;
202 
203 	while (vq_has_descs(vq)) {
204 		n = vq_getchain(vq, iov, VT9P_MAX_IOV, &req);
205 		assert(n >= 1 && n <= VT9P_MAX_IOV);
206 		preq = calloc(1, sizeof(struct pci_vt9p_request));
207 		preq->vsr_sc = sc;
208 		preq->vsr_idx = req.idx;
209 		preq->vsr_iov = iov;
210 		preq->vsr_niov = n;
211 		preq->vsr_respidx = req.readable;
212 
213 		for (int i = 0; i < n; i++) {
214 			DPRINTF(("vt9p: vt9p_notify(): desc%d base=%p, "
215 			    "len=%zu\r\n", i, iov[i].iov_base,
216 			    iov[i].iov_len));
217 		}
218 
219 		l9p_connection_recv(sc->vsc_conn, iov, preq->vsr_respidx, preq);
220 	}
221 }
222 
223 static int
224 pci_vt9p_legacy_config(nvlist_t *nvl, const char *opts)
225 {
226 	char *sharename = NULL, *tofree, *token, *tokens;
227 
228 	if (opts == NULL)
229 		return (0);
230 
231 	tokens = tofree = strdup(opts);
232 	while ((token = strsep(&tokens, ",")) != NULL) {
233 		if (strchr(token, '=') != NULL) {
234 			if (sharename != NULL) {
235 				EPRINTLN(
236 			    "virtio-9p: more than one share name given");
237 				return (-1);
238 			}
239 
240 			sharename = strsep(&token, "=");
241 			set_config_value_node(nvl, "sharename", sharename);
242 			set_config_value_node(nvl, "path", token);
243 		} else
244 			set_config_bool_node(nvl, token, true);
245 	}
246 	free(tofree);
247 	return (0);
248 }
249 
250 static int
251 pci_vt9p_init(struct vmctx *ctx __unused, struct pci_devinst *pi, nvlist_t *nvl)
252 {
253 	struct pci_vt9p_softc *sc;
254 	const char *value;
255 	const char *sharename;
256 	int rootfd;
257 	bool ro;
258 	cap_rights_t rootcap;
259 
260 	ro = get_config_bool_node_default(nvl, "ro", false);
261 
262 	value = get_config_value_node(nvl, "path");
263 	if (value == NULL) {
264 		EPRINTLN("virtio-9p: path required");
265 		return (1);
266 	}
267 	rootfd = open(value, O_DIRECTORY);
268 	if (rootfd < 0) {
269 		EPRINTLN("virtio-9p: failed to open '%s': %s", value,
270 		    strerror(errno));
271 		return (-1);
272 	}
273 
274 	sharename = get_config_value_node(nvl, "sharename");
275 	if (sharename == NULL) {
276 		EPRINTLN("virtio-9p: share name required");
277 		return (1);
278 	}
279 	if (strlen(sharename) > VT9P_MAXTAGSZ) {
280 		EPRINTLN("virtio-9p: share name too long");
281 		return (1);
282 	}
283 
284 	sc = calloc(1, sizeof(struct pci_vt9p_softc));
285 	sc->vsc_config = calloc(1, sizeof(struct pci_vt9p_config) +
286 	    VT9P_MAXTAGSZ);
287 
288 	pthread_mutex_init(&sc->vsc_mtx, NULL);
289 
290 	cap_rights_init(&rootcap,
291 	    CAP_LOOKUP, CAP_ACL_CHECK, CAP_ACL_DELETE, CAP_ACL_GET,
292 	    CAP_ACL_SET, CAP_READ, CAP_WRITE, CAP_SEEK, CAP_FSTAT,
293 	    CAP_CREATE, CAP_FCHMODAT, CAP_FCHOWNAT, CAP_FTRUNCATE,
294 	    CAP_LINKAT_SOURCE, CAP_LINKAT_TARGET, CAP_MKDIRAT, CAP_MKNODAT,
295 	    CAP_PREAD, CAP_PWRITE, CAP_RENAMEAT_SOURCE, CAP_RENAMEAT_TARGET,
296 	    CAP_SEEK, CAP_SYMLINKAT, CAP_UNLINKAT, CAP_EXTATTR_DELETE,
297 	    CAP_EXTATTR_GET, CAP_EXTATTR_LIST, CAP_EXTATTR_SET,
298 	    CAP_FUTIMES, CAP_FSTATFS, CAP_FSYNC, CAP_FPATHCONF);
299 
300 	if (cap_rights_limit(rootfd, &rootcap) != 0)
301 		return (1);
302 
303 	sc->vsc_config->tag_len = (uint16_t)strlen(sharename);
304 	memcpy(sc->vsc_config->tag, sharename, sc->vsc_config->tag_len);
305 
306 	if (l9p_backend_fs_init(&sc->vsc_fs_backend, rootfd, ro) != 0) {
307 		errno = ENXIO;
308 		return (1);
309 	}
310 
311 	if (l9p_server_init(&sc->vsc_server, sc->vsc_fs_backend) != 0) {
312 		errno = ENXIO;
313 		return (1);
314 	}
315 
316 	if (l9p_connection_init(sc->vsc_server, &sc->vsc_conn) != 0) {
317 		errno = EIO;
318 		return (1);
319 	}
320 
321 	sc->vsc_conn->lc_msize = L9P_MAX_IOV * PAGE_SIZE;
322 	sc->vsc_conn->lc_lt.lt_get_response_buffer = pci_vt9p_get_buffer;
323 	sc->vsc_conn->lc_lt.lt_send_response = pci_vt9p_send;
324 	sc->vsc_conn->lc_lt.lt_drop_response = pci_vt9p_drop;
325 
326 	vi_softc_linkup(&sc->vsc_vs, &vt9p_vi_consts, sc, pi, &sc->vsc_vq);
327 	sc->vsc_vs.vs_mtx = &sc->vsc_mtx;
328 	sc->vsc_vq.vq_qsize = VT9P_RINGSZ;
329 
330 	/* initialize config space */
331 	pci_set_cfgdata16(pi, PCIR_DEVICE, VIRTIO_DEV_9P);
332 	pci_set_cfgdata16(pi, PCIR_VENDOR, VIRTIO_VENDOR);
333 	pci_set_cfgdata8(pi, PCIR_CLASS, PCIC_STORAGE);
334 	pci_set_cfgdata16(pi, PCIR_SUBDEV_0, VIRTIO_ID_9P);
335 	pci_set_cfgdata16(pi, PCIR_SUBVEND_0, VIRTIO_VENDOR);
336 
337 	if (vi_intr_init(&sc->vsc_vs, 1, fbsdrun_virtio_msix()))
338 		return (1);
339 	vi_set_io_bar(&sc->vsc_vs, 0);
340 
341 	return (0);
342 }
343 
344 static const struct pci_devemu pci_de_v9p = {
345 	.pe_emu =	"virtio-9p",
346 	.pe_legacy_config = pci_vt9p_legacy_config,
347 	.pe_init =	pci_vt9p_init,
348 	.pe_barwrite =	vi_pci_write,
349 	.pe_barread =	vi_pci_read
350 };
351 PCI_EMUL_SET(pci_de_v9p);
352