xref: /freebsd/usr.sbin/bhyve/pci_virtio_9p.c (revision 5def4c47d4bd90b209b9b4a4ba9faec15846d8fd)
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 	"vt9p",			/* our name */
109 	1,			/* we support 1 virtqueue */
110 	VT9P_CONFIGSPACESZ,	/* config reg size */
111 	pci_vt9p_reset,		/* reset */
112 	pci_vt9p_notify,	/* device-wide qnotify */
113 	pci_vt9p_cfgread,	/* read virtio config */
114 	NULL,			/* write virtio config */
115 	pci_vt9p_neg_features,	/* apply negotiated features */
116 	(1 << 0),		/* our capabilities */
117 };
118 
119 
120 static void
121 pci_vt9p_reset(void *vsc)
122 {
123 	struct pci_vt9p_softc *sc;
124 
125 	sc = vsc;
126 
127 	DPRINTF(("vt9p: device reset requested !\n"));
128 	vi_reset_dev(&sc->vsc_vs);
129 }
130 
131 static void
132 pci_vt9p_neg_features(void *vsc, uint64_t negotiated_features)
133 {
134 	struct pci_vt9p_softc *sc = vsc;
135 
136 	sc->vsc_features = negotiated_features;
137 }
138 
139 static int
140 pci_vt9p_cfgread(void *vsc, int offset, int size, uint32_t *retval)
141 {
142 	struct pci_vt9p_softc *sc = vsc;
143 	void *ptr;
144 
145 	ptr = (uint8_t *)sc->vsc_config + offset;
146 	memcpy(retval, ptr, size);
147 	return (0);
148 }
149 
150 static int
151 pci_vt9p_get_buffer(struct l9p_request *req, struct iovec *iov, size_t *niov,
152     void *arg)
153 {
154 	struct pci_vt9p_request *preq = req->lr_aux;
155 	size_t n = preq->vsr_niov - preq->vsr_respidx;
156 
157 	memcpy(iov, preq->vsr_iov + preq->vsr_respidx,
158 	    n * sizeof(struct iovec));
159 	*niov = n;
160 	return (0);
161 }
162 
163 static int
164 pci_vt9p_send(struct l9p_request *req, const struct iovec *iov,
165     const size_t niov, const size_t iolen, void *arg)
166 {
167 	struct pci_vt9p_request *preq = req->lr_aux;
168 	struct pci_vt9p_softc *sc = preq->vsr_sc;
169 
170 	preq->vsr_iolen = iolen;
171 
172 	pthread_mutex_lock(&sc->vsc_mtx);
173 	vq_relchain(&sc->vsc_vq, preq->vsr_idx, preq->vsr_iolen);
174 	vq_endchains(&sc->vsc_vq, 1);
175 	pthread_mutex_unlock(&sc->vsc_mtx);
176 	free(preq);
177 	return (0);
178 }
179 
180 static void
181 pci_vt9p_drop(struct l9p_request *req, const struct iovec *iov, size_t niov,
182     void *arg)
183 {
184 	struct pci_vt9p_request *preq = req->lr_aux;
185 	struct pci_vt9p_softc *sc = preq->vsr_sc;
186 
187 	pthread_mutex_lock(&sc->vsc_mtx);
188 	vq_relchain(&sc->vsc_vq, preq->vsr_idx, 0);
189 	vq_endchains(&sc->vsc_vq, 1);
190 	pthread_mutex_unlock(&sc->vsc_mtx);
191 	free(preq);
192 }
193 
194 static void
195 pci_vt9p_notify(void *vsc, struct vqueue_info *vq)
196 {
197 	struct iovec iov[VT9P_MAX_IOV];
198 	struct pci_vt9p_softc *sc;
199 	struct pci_vt9p_request *preq;
200 	struct vi_req req;
201 	uint16_t n;
202 
203 	sc = vsc;
204 
205 	while (vq_has_descs(vq)) {
206 		n = vq_getchain(vq, iov, VT9P_MAX_IOV, &req);
207 		preq = calloc(1, sizeof(struct pci_vt9p_request));
208 		preq->vsr_sc = sc;
209 		preq->vsr_idx = req.idx;
210 		preq->vsr_iov = iov;
211 		preq->vsr_niov = n;
212 		preq->vsr_respidx = req.readable;
213 
214 		for (int i = 0; i < n; i++) {
215 			DPRINTF(("vt9p: vt9p_notify(): desc%d base=%p, "
216 			    "len=%zu\r\n", i, iov[i].iov_base,
217 			    iov[i].iov_len));
218 		}
219 
220 		l9p_connection_recv(sc->vsc_conn, iov, preq->vsr_respidx, preq);
221 	}
222 }
223 
224 static int
225 pci_vt9p_legacy_config(nvlist_t *nvl, const char *opts)
226 {
227 	char *sharename = NULL, *tofree, *token, *tokens;
228 
229 	if (opts == NULL)
230 		return (0);
231 
232 	tokens = tofree = strdup(opts);
233 	while ((token = strsep(&tokens, ",")) != NULL) {
234 		if (strchr(token, '=') != NULL) {
235 			if (sharename != NULL) {
236 				EPRINTLN(
237 			    "virtio-9p: more than one share name given");
238 				return (-1);
239 			}
240 
241 			sharename = strsep(&token, "=");
242 			set_config_value_node(nvl, "sharename", sharename);
243 			set_config_value_node(nvl, "path", token);
244 		} else
245 			set_config_bool_node(nvl, token, true);
246 	}
247 	free(tofree);
248 	return (0);
249 }
250 
251 static int
252 pci_vt9p_init(struct vmctx *ctx, struct pci_devinst *pi, nvlist_t *nvl)
253 {
254 	struct pci_vt9p_softc *sc;
255 	const char *value;
256 	const char *sharename;
257 	int rootfd;
258 	bool ro;
259 	cap_rights_t rootcap;
260 
261 	ro = get_config_bool_node_default(nvl, "ro", false);
262 
263 	value = get_config_value_node(nvl, "path");
264 	if (value == NULL) {
265 		EPRINTLN("virtio-9p: path required");
266 		return (1);
267 	}
268 	rootfd = open(value, O_DIRECTORY);
269 	if (rootfd < 0) {
270 		EPRINTLN("virtio-9p: failed to open '%s': %s", value,
271 		    strerror(errno));
272 		return (-1);
273 	}
274 
275 	sharename = get_config_value_node(nvl, "sharename");
276 	if (sharename == NULL) {
277 		EPRINTLN("virtio-9p: share name required");
278 		return (1);
279 	}
280 	if (strlen(sharename) > VT9P_MAXTAGSZ) {
281 		EPRINTLN("virtio-9p: share name too long");
282 		return (1);
283 	}
284 
285 	sc = calloc(1, sizeof(struct pci_vt9p_softc));
286 	sc->vsc_config = calloc(1, sizeof(struct pci_vt9p_config) +
287 	    VT9P_MAXTAGSZ);
288 
289 	pthread_mutex_init(&sc->vsc_mtx, NULL);
290 
291 	cap_rights_init(&rootcap,
292 	    CAP_LOOKUP, CAP_ACL_CHECK, CAP_ACL_DELETE, CAP_ACL_GET,
293 	    CAP_ACL_SET, CAP_READ, CAP_WRITE, CAP_SEEK, CAP_FSTAT,
294 	    CAP_CREATE, CAP_FCHMODAT, CAP_FCHOWNAT, CAP_FTRUNCATE,
295 	    CAP_LINKAT_SOURCE, CAP_LINKAT_TARGET, CAP_MKDIRAT, CAP_MKNODAT,
296 	    CAP_PREAD, CAP_PWRITE, CAP_RENAMEAT_SOURCE, CAP_RENAMEAT_TARGET,
297 	    CAP_SEEK, CAP_SYMLINKAT, CAP_UNLINKAT, CAP_EXTATTR_DELETE,
298 	    CAP_EXTATTR_GET, CAP_EXTATTR_LIST, CAP_EXTATTR_SET,
299 	    CAP_FUTIMES, CAP_FSTATFS, CAP_FSYNC, CAP_FPATHCONF);
300 
301 	if (cap_rights_limit(rootfd, &rootcap) != 0)
302 		return (1);
303 
304 	sc->vsc_config->tag_len = (uint16_t)strlen(sharename);
305 	memcpy(sc->vsc_config->tag, sharename, sc->vsc_config->tag_len);
306 
307 	if (l9p_backend_fs_init(&sc->vsc_fs_backend, rootfd, ro) != 0) {
308 		errno = ENXIO;
309 		return (1);
310 	}
311 
312 	if (l9p_server_init(&sc->vsc_server, sc->vsc_fs_backend) != 0) {
313 		errno = ENXIO;
314 		return (1);
315 	}
316 
317 	if (l9p_connection_init(sc->vsc_server, &sc->vsc_conn) != 0) {
318 		errno = EIO;
319 		return (1);
320 	}
321 
322 	sc->vsc_conn->lc_msize = L9P_MAX_IOV * PAGE_SIZE;
323 	sc->vsc_conn->lc_lt.lt_get_response_buffer = pci_vt9p_get_buffer;
324 	sc->vsc_conn->lc_lt.lt_send_response = pci_vt9p_send;
325 	sc->vsc_conn->lc_lt.lt_drop_response = pci_vt9p_drop;
326 
327 	vi_softc_linkup(&sc->vsc_vs, &vt9p_vi_consts, sc, pi, &sc->vsc_vq);
328 	sc->vsc_vs.vs_mtx = &sc->vsc_mtx;
329 	sc->vsc_vq.vq_qsize = VT9P_RINGSZ;
330 
331 	/* initialize config space */
332 	pci_set_cfgdata16(pi, PCIR_DEVICE, VIRTIO_DEV_9P);
333 	pci_set_cfgdata16(pi, PCIR_VENDOR, VIRTIO_VENDOR);
334 	pci_set_cfgdata8(pi, PCIR_CLASS, PCIC_STORAGE);
335 	pci_set_cfgdata16(pi, PCIR_SUBDEV_0, VIRTIO_ID_9P);
336 	pci_set_cfgdata16(pi, PCIR_SUBVEND_0, VIRTIO_VENDOR);
337 
338 	if (vi_intr_init(&sc->vsc_vs, 1, fbsdrun_virtio_msix()))
339 		return (1);
340 	vi_set_io_bar(&sc->vsc_vs, 0);
341 
342 	return (0);
343 }
344 
345 struct pci_devemu pci_de_v9p = {
346 	.pe_emu =	"virtio-9p",
347 	.pe_legacy_config = pci_vt9p_legacy_config,
348 	.pe_init =	pci_vt9p_init,
349 	.pe_barwrite =	vi_pci_write,
350 	.pe_barread =	vi_pci_read
351 };
352 PCI_EMUL_SET(pci_de_v9p);
353