xref: /freebsd/contrib/lib9p/connection.c (revision dd41de95a84d979615a2ef11df6850622bf6184e)
1 /*
2  * Copyright 2016 Jakub Klama <jceel@FreeBSD.org>
3  * All rights reserved
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted providing 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  * 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
16  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
18  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
22  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
23  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
24  * POSSIBILITY OF SUCH DAMAGE.
25  *
26  */
27 
28 #include <stdlib.h>
29 #include <string.h>
30 #include <errno.h>
31 #include <assert.h>
32 #include <sys/queue.h>
33 #include "lib9p.h"
34 #include "lib9p_impl.h"
35 #include "fid.h"
36 #include "hashtable.h"
37 #include "log.h"
38 #include "threadpool.h"
39 #include "backend/backend.h"
40 
41 int
42 l9p_server_init(struct l9p_server **serverp, struct l9p_backend *backend)
43 {
44 	struct l9p_server *server;
45 
46 	server = l9p_calloc(1, sizeof (*server));
47 	server->ls_max_version = L9P_2000L;
48 	server->ls_backend = backend;
49 	LIST_INIT(&server->ls_conns);
50 
51 	*serverp = server;
52 	return (0);
53 }
54 
55 int
56 l9p_connection_init(struct l9p_server *server, struct l9p_connection **conn)
57 {
58 	struct l9p_connection *newconn;
59 
60 	assert(server != NULL);
61 	assert(conn != NULL);
62 
63 	newconn = calloc(1, sizeof (*newconn));
64 	if (newconn == NULL)
65 		return (-1);
66 	newconn->lc_server = server;
67 	newconn->lc_msize = L9P_DEFAULT_MSIZE;
68 	if (l9p_threadpool_init(&newconn->lc_tp, L9P_NUMTHREADS)) {
69 		free(newconn);
70 		return (-1);
71 	}
72 	ht_init(&newconn->lc_files, 100);
73 	ht_init(&newconn->lc_requests, 100);
74 	LIST_INSERT_HEAD(&server->ls_conns, newconn, lc_link);
75 	*conn = newconn;
76 
77 	return (0);
78 }
79 
80 void
81 l9p_connection_free(struct l9p_connection *conn)
82 {
83 
84 	LIST_REMOVE(conn, lc_link);
85 	free(conn);
86 }
87 
88 void
89 l9p_connection_recv(struct l9p_connection *conn, const struct iovec *iov,
90     const size_t niov, void *aux)
91 {
92 	struct l9p_request *req;
93 	int error;
94 
95 	req = l9p_calloc(1, sizeof (struct l9p_request));
96 	req->lr_aux = aux;
97 	req->lr_conn = conn;
98 
99 	req->lr_req_msg.lm_mode = L9P_UNPACK;
100 	req->lr_req_msg.lm_niov = niov;
101 	memcpy(req->lr_req_msg.lm_iov, iov, sizeof (struct iovec) * niov);
102 
103 	req->lr_resp_msg.lm_mode = L9P_PACK;
104 
105 	if (l9p_pufcall(&req->lr_req_msg, &req->lr_req, conn->lc_version) != 0) {
106 		L9P_LOG(L9P_WARNING, "cannot unpack received message");
107 		l9p_freefcall(&req->lr_req);
108 		free(req);
109 		return;
110 	}
111 
112 	if (ht_add(&conn->lc_requests, req->lr_req.hdr.tag, req)) {
113 		L9P_LOG(L9P_WARNING, "client reusing outstanding tag %d",
114 		    req->lr_req.hdr.tag);
115 		l9p_freefcall(&req->lr_req);
116 		free(req);
117 		return;
118 	}
119 
120 	error = conn->lc_lt.lt_get_response_buffer(req,
121 	    req->lr_resp_msg.lm_iov,
122 	    &req->lr_resp_msg.lm_niov,
123 	    conn->lc_lt.lt_aux);
124 	if (error) {
125 		L9P_LOG(L9P_WARNING, "cannot obtain buffers for response");
126 		ht_remove(&conn->lc_requests, req->lr_req.hdr.tag);
127 		l9p_freefcall(&req->lr_req);
128 		free(req);
129 		return;
130 	}
131 
132 	/*
133 	 * NB: it's up to l9p_threadpool_run to decide whether
134 	 * to queue the work or to run it immediately and wait
135 	 * (it must do the latter for Tflush requests).
136 	 */
137 	l9p_threadpool_run(&conn->lc_tp, req);
138 }
139 
140 void
141 l9p_connection_close(struct l9p_connection *conn)
142 {
143 	struct ht_iter iter;
144 	struct l9p_fid *fid;
145 	struct l9p_request *req;
146 
147 	L9P_LOG(L9P_DEBUG, "waiting for thread pool to shut down");
148 	l9p_threadpool_shutdown(&conn->lc_tp);
149 
150 	/* Drain pending requests (if any) */
151 	L9P_LOG(L9P_DEBUG, "draining pending requests");
152 	ht_iter(&conn->lc_requests, &iter);
153 	while ((req = ht_next(&iter)) != NULL) {
154 #ifdef notyet
155 		/* XXX would be good to know if there is anyone listening */
156 		if (anyone listening) {
157 			/* XXX crude - ops like Tclunk should succeed */
158 			req->lr_error = EINTR;
159 			l9p_respond(req, false, false);
160 		} else
161 #endif
162 		l9p_respond(req, true, false);	/* use no-answer path */
163 		ht_remove_at_iter(&iter);
164 	}
165 
166 	/* Close opened files (if any) */
167 	L9P_LOG(L9P_DEBUG, "closing opened files");
168 	ht_iter(&conn->lc_files, &iter);
169 	while ((fid = ht_next(&iter)) != NULL) {
170 		conn->lc_server->ls_backend->freefid(
171 		    conn->lc_server->ls_backend->softc, fid);
172 		free(fid);
173 		ht_remove_at_iter(&iter);
174 	}
175 
176 	ht_destroy(&conn->lc_requests);
177 	ht_destroy(&conn->lc_files);
178 }
179 
180 struct l9p_fid *
181 l9p_connection_alloc_fid(struct l9p_connection *conn, uint32_t fid)
182 {
183 	struct l9p_fid *file;
184 
185 	file = l9p_calloc(1, sizeof (struct l9p_fid));
186 	file->lo_fid = fid;
187 	/*
188 	 * Note that the new fid is not marked valid yet.
189 	 * The insert here will fail if the fid number is
190 	 * in use, otherwise we have an invalid fid in the
191 	 * table (as desired).
192 	 */
193 
194 	if (ht_add(&conn->lc_files, fid, file) != 0) {
195 		free(file);
196 		return (NULL);
197 	}
198 
199 	return (file);
200 }
201 
202 void
203 l9p_connection_remove_fid(struct l9p_connection *conn, struct l9p_fid *fid)
204 {
205 	struct l9p_backend *be;
206 
207 	/* fid should be marked invalid by this point */
208 	assert(!l9p_fid_isvalid(fid));
209 
210 	be = conn->lc_server->ls_backend;
211 	be->freefid(be->softc, fid);
212 
213 	ht_remove(&conn->lc_files, fid->lo_fid);
214 	free(fid);
215 }
216