xref: /dflybsd-src/sys/vfs/nfs/nfs_iod.c (revision f8565b0fd3905ebd9fb24ff83243c0b4cb3c0ea9)
1 /*
2  * Copyright (c) 2009 The DragonFly Project.  All rights reserved.
3  *
4  * This code is derived from software contributed to The DragonFly Project
5  * by Matthew Dillon <dillon@backplane.com>
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in
15  *    the documentation and/or other materials provided with the
16  *    distribution.
17  * 3. Neither the name of The DragonFly Project nor the names of its
18  *    contributors may be used to endorse or promote products derived
19  *    from this software without specific, prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 /*
35  * NFSIOD operations - now built into the kernel.
36  */
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/proc.h>
40 #include <sys/malloc.h>
41 #include <sys/mount.h>
42 #include <sys/kernel.h>
43 #include <sys/mbuf.h>
44 #include <sys/vnode.h>
45 #include <sys/fcntl.h>
46 #include <sys/protosw.h>
47 #include <sys/resourcevar.h>
48 #include <sys/socket.h>
49 #include <sys/socketvar.h>
50 #include <sys/socketops.h>
51 #include <sys/syslog.h>
52 #include <sys/thread.h>
53 #include <sys/tprintf.h>
54 #include <sys/sysctl.h>
55 #include <sys/signalvar.h>
56 #include <sys/mutex.h>
57 
58 #include <sys/signal2.h>
59 #include <sys/mutex2.h>
60 
61 #include <netinet/in.h>
62 #include <netinet/tcp.h>
63 #include <sys/thread2.h>
64 
65 #include "rpcv2.h"
66 #include "nfsproto.h"
67 #include "nfs.h"
68 #include "xdr_subs.h"
69 #include "nfsm_subs.h"
70 #include "nfsmount.h"
71 #include "nfsnode.h"
72 #include "nfsrtt.h"
73 
74 void
75 nfssvc_iod_reader(void *arg)
76 {
77 	struct nfsmount *nmp = arg;
78 	struct nfsm_info *info;
79 	struct nfsreq *req;
80 	int error;
81 
82 	if (nmp->nm_rxstate == NFSSVC_INIT)
83 		nmp->nm_rxstate = NFSSVC_PENDING;
84 	crit_enter();
85 	for (;;) {
86 		if (nmp->nm_rxstate == NFSSVC_WAITING) {
87 			if (TAILQ_FIRST(&nmp->nm_reqq) == NULL &&
88 			    TAILQ_FIRST(&nmp->nm_reqrxq) == NULL) {
89 				tsleep(&nmp->nm_rxstate, 0, "nfsidl", 0);
90 			} else {
91 				/*
92 				 * This can happen during shutdown, we don't
93 				 * want to hardloop.
94 				 */
95 				error = nfs_reply(nmp, NULL);
96 				if (error && error != EWOULDBLOCK) {
97 					tsleep(&nmp->nm_rxstate, 0,
98 						"nfsxxx", hz / 10);
99 				}
100 			}
101 			continue;
102 		}
103 		if (nmp->nm_rxstate != NFSSVC_PENDING)
104 			break;
105 		nmp->nm_rxstate = NFSSVC_WAITING;
106 
107 		/*
108 		 * Process requests which have received replies.  Only
109 		 * process the post-reply states.  If we get EINPROGRESS
110 		 * it means the request went back to an auth or retransmit
111 		 * state and we let the iod_writer thread deal with it.
112 		 *
113 		 * Any lock on the request is strictly temporary due to
114 		 * MP races (XXX).
115 		 *
116 		 * If the request completes we run the info->done call
117 		 * to finish up the I/O.
118 		 */
119 		while ((req = TAILQ_FIRST(&nmp->nm_reqrxq)) != NULL) {
120 			if (req->r_flags & R_LOCKED) {
121 				while (req->r_flags & R_LOCKED) {
122 					req->r_flags |= R_WANTED;
123 					tsleep(req, 0, "nfstrac", 0);
124 				}
125 				continue;
126 			}
127 			TAILQ_REMOVE(&nmp->nm_reqrxq, req, r_chain);
128 			crit_exit();
129 			info = req->r_info;
130 			KKASSERT(info);
131 			info->error = nfs_request(info,
132 						  NFSM_STATE_PROCESSREPLY,
133 						  NFSM_STATE_DONE);
134 			if (info->error == EINPROGRESS) {
135 				kprintf("rxq: move info %p back to txq\n", info);
136 				TAILQ_INSERT_TAIL(&nmp->nm_reqtxq, req, r_chain);
137 				nfssvc_iod_writer_wakeup(nmp);
138 			} else {
139 				atomic_subtract_int(&nmp->nm_bioqlen, 1);
140 				info->done(info);
141 			}
142 			crit_enter();
143 		}
144 	}
145 	crit_exit();
146 	nmp->nm_rxthread = NULL;
147 	nmp->nm_rxstate = NFSSVC_DONE;
148 	wakeup(&nmp->nm_rxthread);
149 }
150 
151 /*
152  * The writer sits on the send side of the client's socket and
153  * does both the initial processing of BIOs and also transmission
154  * and retransmission of nfsreq's.
155  *
156  * The writer processes both new BIOs from nm_bioq and retransmit
157  * or state machine jumpbacks from nm_reqtxq
158  */
159 void
160 nfssvc_iod_writer(void *arg)
161 {
162 	struct nfsmount *nmp = arg;
163 	struct bio *bio;
164 	struct nfsreq *req;
165 	struct vnode *vp;
166 	nfsm_info_t info;
167 
168 	if (nmp->nm_txstate == NFSSVC_INIT)
169 		nmp->nm_txstate = NFSSVC_PENDING;
170 	crit_enter();
171 	for (;;) {
172 		if (nmp->nm_txstate == NFSSVC_WAITING) {
173 			tsleep(&nmp->nm_txstate, 0, "nfsidl", 0);
174 			continue;
175 		}
176 		if (nmp->nm_txstate != NFSSVC_PENDING)
177 			break;
178 		nmp->nm_txstate = NFSSVC_WAITING;
179 
180 		while ((bio = TAILQ_FIRST(&nmp->nm_bioq)) != NULL) {
181 			TAILQ_REMOVE(&nmp->nm_bioq, bio, bio_act);
182 			vp = bio->bio_driver_info;
183 			crit_exit();
184 			nfs_startio(vp, bio, NULL);
185 			crit_enter();
186 		}
187 
188 		/*
189 		 * Process reauths & retransmits.  If we get an EINPROGRESS
190 		 * it means the state transitioned to WAITREPLY or later.
191 		 * Otherwise the request completed (probably with an error
192 		 * since we didn't get to a replied state).
193 		 */
194 		while ((req = TAILQ_FIRST(&nmp->nm_reqtxq)) != NULL) {
195 			TAILQ_REMOVE(&nmp->nm_reqtxq, req, r_chain);
196 			info = req->r_info;
197 			KKASSERT(info);
198 			crit_exit();
199 			info->error = nfs_request(info,
200 						  NFSM_STATE_AUTH,
201 						  NFSM_STATE_WAITREPLY);
202 			crit_enter();
203 			if (info->error == EINPROGRESS) {
204 				;
205 			} else {
206 				atomic_subtract_int(&nmp->nm_bioqlen, 1);
207 				info->done(info);
208 			}
209 		}
210 	}
211 	crit_exit();
212 	nmp->nm_txthread = NULL;
213 	nmp->nm_txstate = NFSSVC_DONE;
214 	wakeup(&nmp->nm_txthread);
215 }
216 
217 void
218 nfssvc_iod_stop1(struct nfsmount *nmp)
219 {
220 	crit_enter();
221 	nmp->nm_txstate = NFSSVC_STOPPING;
222 	nmp->nm_rxstate = NFSSVC_STOPPING;
223 	crit_exit();
224 }
225 
226 void
227 nfssvc_iod_stop2(struct nfsmount *nmp)
228 {
229 	wakeup(&nmp->nm_txstate);
230 	while (nmp->nm_txthread)
231 		tsleep(&nmp->nm_txthread, 0, "nfssttx", 0);
232 	wakeup(&nmp->nm_rxstate);
233 	while (nmp->nm_rxthread)
234 		tsleep(&nmp->nm_rxthread, 0, "nfsstrx", 0);
235 }
236 
237 
238 void
239 nfssvc_iod_writer_wakeup(struct nfsmount *nmp)
240 {
241 	if (nmp->nm_txstate == NFSSVC_WAITING) {
242 		nmp->nm_txstate = NFSSVC_PENDING;
243 		wakeup(&nmp->nm_txstate);
244 	}
245 }
246 
247 void
248 nfssvc_iod_reader_wakeup(struct nfsmount *nmp)
249 {
250 	if (nmp->nm_rxstate == NFSSVC_WAITING) {
251 		nmp->nm_rxstate = NFSSVC_PENDING;
252 		wakeup(&nmp->nm_rxstate);
253 	}
254 }
255