Commit | Line | Data |
---|---|---|
1d8206b9 TT |
1 | /* |
2 | * linux/net/sunrpc/svc_xprt.c | |
3 | * | |
4 | * Author: Tom Tucker <tom@opengridcomputing.com> | |
5 | */ | |
6 | ||
7 | #include <linux/sched.h> | |
8 | #include <linux/errno.h> | |
1d8206b9 | 9 | #include <linux/freezer.h> |
7086721f | 10 | #include <linux/kthread.h> |
5a0e3ad6 | 11 | #include <linux/slab.h> |
1d8206b9 | 12 | #include <net/sock.h> |
1d8206b9 TT |
13 | #include <linux/sunrpc/stats.h> |
14 | #include <linux/sunrpc/svc_xprt.h> | |
dcf1a357 | 15 | #include <linux/sunrpc/svcsock.h> |
99de8ea9 | 16 | #include <linux/sunrpc/xprt.h> |
3a9a231d | 17 | #include <linux/module.h> |
860a0d9e | 18 | #include <trace/events/sunrpc.h> |
1d8206b9 TT |
19 | |
20 | #define RPCDBG_FACILITY RPCDBG_SVCXPRT | |
21 | ||
0f0257ea TT |
22 | static struct svc_deferred_req *svc_deferred_dequeue(struct svc_xprt *xprt); |
23 | static int svc_deferred_recv(struct svc_rqst *rqstp); | |
24 | static struct cache_deferred_req *svc_defer(struct cache_req *req); | |
25 | static void svc_age_temp_xprts(unsigned long closure); | |
7710ec36 | 26 | static void svc_delete_xprt(struct svc_xprt *xprt); |
0971374e | 27 | static void svc_xprt_do_enqueue(struct svc_xprt *xprt); |
0f0257ea TT |
28 | |
29 | /* apparently the "standard" is that clients close | |
30 | * idle connections after 5 minutes, servers after | |
31 | * 6 minutes | |
32 | * http://www.connectathon.org/talks96/nfstcp.pdf | |
33 | */ | |
34 | static int svc_conn_age_period = 6*60; | |
35 | ||
1d8206b9 TT |
36 | /* List of registered transport classes */ |
37 | static DEFINE_SPINLOCK(svc_xprt_class_lock); | |
38 | static LIST_HEAD(svc_xprt_class_list); | |
39 | ||
0f0257ea TT |
40 | /* SMP locking strategy: |
41 | * | |
42 | * svc_pool->sp_lock protects most of the fields of that pool. | |
43 | * svc_serv->sv_lock protects sv_tempsocks, sv_permsocks, sv_tmpcnt. | |
44 | * when both need to be taken (rare), svc_serv->sv_lock is first. | |
45 | * BKL protects svc_serv->sv_nrthread. | |
46 | * svc_sock->sk_lock protects the svc_sock->sk_deferred list | |
47 | * and the ->sk_info_authunix cache. | |
48 | * | |
49 | * The XPT_BUSY bit in xprt->xpt_flags prevents a transport being | |
50 | * enqueued multiply. During normal transport processing this bit | |
51 | * is set by svc_xprt_enqueue and cleared by svc_xprt_received. | |
52 | * Providers should not manipulate this bit directly. | |
53 | * | |
54 | * Some flags can be set to certain values at any time | |
55 | * providing that certain rules are followed: | |
56 | * | |
57 | * XPT_CONN, XPT_DATA: | |
58 | * - Can be set or cleared at any time. | |
59 | * - After a set, svc_xprt_enqueue must be called to enqueue | |
60 | * the transport for processing. | |
61 | * - After a clear, the transport must be read/accepted. | |
62 | * If this succeeds, it must be set again. | |
63 | * XPT_CLOSE: | |
64 | * - Can set at any time. It is never cleared. | |
65 | * XPT_DEAD: | |
66 | * - Can only be set while XPT_BUSY is held which ensures | |
67 | * that no other thread will be using the transport or will | |
68 | * try to set XPT_DEAD. | |
69 | */ | |
70 | ||
1d8206b9 TT |
71 | int svc_reg_xprt_class(struct svc_xprt_class *xcl) |
72 | { | |
73 | struct svc_xprt_class *cl; | |
74 | int res = -EEXIST; | |
75 | ||
76 | dprintk("svc: Adding svc transport class '%s'\n", xcl->xcl_name); | |
77 | ||
78 | INIT_LIST_HEAD(&xcl->xcl_list); | |
79 | spin_lock(&svc_xprt_class_lock); | |
80 | /* Make sure there isn't already a class with the same name */ | |
81 | list_for_each_entry(cl, &svc_xprt_class_list, xcl_list) { | |
82 | if (strcmp(xcl->xcl_name, cl->xcl_name) == 0) | |
83 | goto out; | |
84 | } | |
85 | list_add_tail(&xcl->xcl_list, &svc_xprt_class_list); | |
86 | res = 0; | |
87 | out: | |
88 | spin_unlock(&svc_xprt_class_lock); | |
89 | return res; | |
90 | } | |
91 | EXPORT_SYMBOL_GPL(svc_reg_xprt_class); | |
92 | ||
93 | void svc_unreg_xprt_class(struct svc_xprt_class *xcl) | |
94 | { | |
95 | dprintk("svc: Removing svc transport class '%s'\n", xcl->xcl_name); | |
96 | spin_lock(&svc_xprt_class_lock); | |
97 | list_del_init(&xcl->xcl_list); | |
98 | spin_unlock(&svc_xprt_class_lock); | |
99 | } | |
100 | EXPORT_SYMBOL_GPL(svc_unreg_xprt_class); | |
101 | ||
dc9a16e4 TT |
102 | /* |
103 | * Format the transport list for printing | |
104 | */ | |
105 | int svc_print_xprts(char *buf, int maxlen) | |
106 | { | |
8f3a6de3 | 107 | struct svc_xprt_class *xcl; |
dc9a16e4 TT |
108 | char tmpstr[80]; |
109 | int len = 0; | |
110 | buf[0] = '\0'; | |
111 | ||
112 | spin_lock(&svc_xprt_class_lock); | |
8f3a6de3 | 113 | list_for_each_entry(xcl, &svc_xprt_class_list, xcl_list) { |
dc9a16e4 | 114 | int slen; |
dc9a16e4 TT |
115 | |
116 | sprintf(tmpstr, "%s %d\n", xcl->xcl_name, xcl->xcl_max_payload); | |
117 | slen = strlen(tmpstr); | |
118 | if (len + slen > maxlen) | |
119 | break; | |
120 | len += slen; | |
121 | strcat(buf, tmpstr); | |
122 | } | |
123 | spin_unlock(&svc_xprt_class_lock); | |
124 | ||
125 | return len; | |
126 | } | |
127 | ||
e1b3157f TT |
128 | static void svc_xprt_free(struct kref *kref) |
129 | { | |
130 | struct svc_xprt *xprt = | |
131 | container_of(kref, struct svc_xprt, xpt_ref); | |
132 | struct module *owner = xprt->xpt_class->xcl_owner; | |
e3bfca01 PE |
133 | if (test_bit(XPT_CACHE_AUTH, &xprt->xpt_flags)) |
134 | svcauth_unix_info_release(xprt); | |
4fb8518b | 135 | put_net(xprt->xpt_net); |
99de8ea9 BF |
136 | /* See comment on corresponding get in xs_setup_bc_tcp(): */ |
137 | if (xprt->xpt_bc_xprt) | |
138 | xprt_put(xprt->xpt_bc_xprt); | |
e1b3157f TT |
139 | xprt->xpt_ops->xpo_free(xprt); |
140 | module_put(owner); | |
141 | } | |
142 | ||
143 | void svc_xprt_put(struct svc_xprt *xprt) | |
144 | { | |
145 | kref_put(&xprt->xpt_ref, svc_xprt_free); | |
146 | } | |
147 | EXPORT_SYMBOL_GPL(svc_xprt_put); | |
148 | ||
1d8206b9 TT |
149 | /* |
150 | * Called by transport drivers to initialize the transport independent | |
151 | * portion of the transport instance. | |
152 | */ | |
bd4620dd SK |
153 | void svc_xprt_init(struct net *net, struct svc_xprt_class *xcl, |
154 | struct svc_xprt *xprt, struct svc_serv *serv) | |
1d8206b9 TT |
155 | { |
156 | memset(xprt, 0, sizeof(*xprt)); | |
157 | xprt->xpt_class = xcl; | |
158 | xprt->xpt_ops = xcl->xcl_ops; | |
e1b3157f | 159 | kref_init(&xprt->xpt_ref); |
bb5cf160 | 160 | xprt->xpt_server = serv; |
7a182083 TT |
161 | INIT_LIST_HEAD(&xprt->xpt_list); |
162 | INIT_LIST_HEAD(&xprt->xpt_ready); | |
8c7b0172 | 163 | INIT_LIST_HEAD(&xprt->xpt_deferred); |
edc7a894 | 164 | INIT_LIST_HEAD(&xprt->xpt_users); |
a50fea26 | 165 | mutex_init(&xprt->xpt_mutex); |
def13d74 | 166 | spin_lock_init(&xprt->xpt_lock); |
4e5caaa5 | 167 | set_bit(XPT_BUSY, &xprt->xpt_flags); |
4cfc7e60 | 168 | rpc_init_wait_queue(&xprt->xpt_bc_pending, "xpt_bc_pending"); |
bd4620dd | 169 | xprt->xpt_net = get_net(net); |
1d8206b9 TT |
170 | } |
171 | EXPORT_SYMBOL_GPL(svc_xprt_init); | |
b700cbb1 | 172 | |
5dd248f6 CL |
173 | static struct svc_xprt *__svc_xpo_create(struct svc_xprt_class *xcl, |
174 | struct svc_serv *serv, | |
62832c03 | 175 | struct net *net, |
9652ada3 CL |
176 | const int family, |
177 | const unsigned short port, | |
178 | int flags) | |
b700cbb1 | 179 | { |
b700cbb1 TT |
180 | struct sockaddr_in sin = { |
181 | .sin_family = AF_INET, | |
e6f1cebf | 182 | .sin_addr.s_addr = htonl(INADDR_ANY), |
b700cbb1 TT |
183 | .sin_port = htons(port), |
184 | }; | |
dfd56b8b | 185 | #if IS_ENABLED(CONFIG_IPV6) |
5dd248f6 CL |
186 | struct sockaddr_in6 sin6 = { |
187 | .sin6_family = AF_INET6, | |
188 | .sin6_addr = IN6ADDR_ANY_INIT, | |
189 | .sin6_port = htons(port), | |
190 | }; | |
dfd56b8b | 191 | #endif |
5dd248f6 CL |
192 | struct sockaddr *sap; |
193 | size_t len; | |
194 | ||
9652ada3 CL |
195 | switch (family) { |
196 | case PF_INET: | |
5dd248f6 CL |
197 | sap = (struct sockaddr *)&sin; |
198 | len = sizeof(sin); | |
199 | break; | |
dfd56b8b | 200 | #if IS_ENABLED(CONFIG_IPV6) |
9652ada3 | 201 | case PF_INET6: |
5dd248f6 CL |
202 | sap = (struct sockaddr *)&sin6; |
203 | len = sizeof(sin6); | |
204 | break; | |
dfd56b8b | 205 | #endif |
5dd248f6 CL |
206 | default: |
207 | return ERR_PTR(-EAFNOSUPPORT); | |
208 | } | |
209 | ||
62832c03 | 210 | return xcl->xcl_ops->xpo_create(serv, net, sap, len, flags); |
5dd248f6 CL |
211 | } |
212 | ||
6741019c BF |
213 | /* |
214 | * svc_xprt_received conditionally queues the transport for processing | |
215 | * by another thread. The caller must hold the XPT_BUSY bit and must | |
216 | * not thereafter touch transport data. | |
217 | * | |
218 | * Note: XPT_DATA only gets cleared when a read-attempt finds no (or | |
219 | * insufficient) data. | |
220 | */ | |
221 | static void svc_xprt_received(struct svc_xprt *xprt) | |
222 | { | |
acf06a7f JL |
223 | if (!test_bit(XPT_BUSY, &xprt->xpt_flags)) { |
224 | WARN_ONCE(1, "xprt=0x%p already busy!", xprt); | |
ff1fdb9b | 225 | return; |
acf06a7f JL |
226 | } |
227 | ||
6741019c | 228 | /* As soon as we clear busy, the xprt could be closed and |
0971374e | 229 | * 'put', so we need a reference to call svc_xprt_do_enqueue with: |
6741019c BF |
230 | */ |
231 | svc_xprt_get(xprt); | |
0971374e | 232 | smp_mb__before_atomic(); |
6741019c | 233 | clear_bit(XPT_BUSY, &xprt->xpt_flags); |
0971374e | 234 | svc_xprt_do_enqueue(xprt); |
6741019c BF |
235 | svc_xprt_put(xprt); |
236 | } | |
237 | ||
39b55301 BF |
238 | void svc_add_new_perm_xprt(struct svc_serv *serv, struct svc_xprt *new) |
239 | { | |
240 | clear_bit(XPT_TEMP, &new->xpt_flags); | |
241 | spin_lock_bh(&serv->sv_lock); | |
242 | list_add(&new->xpt_list, &serv->sv_permsocks); | |
243 | spin_unlock_bh(&serv->sv_lock); | |
244 | svc_xprt_received(new); | |
245 | } | |
246 | ||
9652ada3 | 247 | int svc_create_xprt(struct svc_serv *serv, const char *xprt_name, |
fc5d00b0 PE |
248 | struct net *net, const int family, |
249 | const unsigned short port, int flags) | |
5dd248f6 CL |
250 | { |
251 | struct svc_xprt_class *xcl; | |
252 | ||
b700cbb1 TT |
253 | dprintk("svc: creating transport %s[%d]\n", xprt_name, port); |
254 | spin_lock(&svc_xprt_class_lock); | |
255 | list_for_each_entry(xcl, &svc_xprt_class_list, xcl_list) { | |
4e5caaa5 | 256 | struct svc_xprt *newxprt; |
ed2849d3 | 257 | unsigned short newport; |
4e5caaa5 TT |
258 | |
259 | if (strcmp(xprt_name, xcl->xcl_name)) | |
260 | continue; | |
261 | ||
262 | if (!try_module_get(xcl->xcl_owner)) | |
263 | goto err; | |
264 | ||
265 | spin_unlock(&svc_xprt_class_lock); | |
62832c03 | 266 | newxprt = __svc_xpo_create(xcl, serv, net, family, port, flags); |
4e5caaa5 TT |
267 | if (IS_ERR(newxprt)) { |
268 | module_put(xcl->xcl_owner); | |
269 | return PTR_ERR(newxprt); | |
b700cbb1 | 270 | } |
39b55301 | 271 | svc_add_new_perm_xprt(serv, newxprt); |
ed2849d3 | 272 | newport = svc_xprt_local_port(newxprt); |
ed2849d3 | 273 | return newport; |
b700cbb1 | 274 | } |
4e5caaa5 | 275 | err: |
b700cbb1 TT |
276 | spin_unlock(&svc_xprt_class_lock); |
277 | dprintk("svc: transport %s not found\n", xprt_name); | |
68717908 CL |
278 | |
279 | /* This errno is exposed to user space. Provide a reasonable | |
280 | * perror msg for a bad transport. */ | |
281 | return -EPROTONOSUPPORT; | |
b700cbb1 TT |
282 | } |
283 | EXPORT_SYMBOL_GPL(svc_create_xprt); | |
9dbc240f TT |
284 | |
285 | /* | |
286 | * Copy the local and remote xprt addresses to the rqstp structure | |
287 | */ | |
288 | void svc_xprt_copy_addrs(struct svc_rqst *rqstp, struct svc_xprt *xprt) | |
289 | { | |
9dbc240f TT |
290 | memcpy(&rqstp->rq_addr, &xprt->xpt_remote, xprt->xpt_remotelen); |
291 | rqstp->rq_addrlen = xprt->xpt_remotelen; | |
292 | ||
293 | /* | |
294 | * Destination address in request is needed for binding the | |
295 | * source address in RPC replies/callbacks later. | |
296 | */ | |
849a1cf1 MJ |
297 | memcpy(&rqstp->rq_daddr, &xprt->xpt_local, xprt->xpt_locallen); |
298 | rqstp->rq_daddrlen = xprt->xpt_locallen; | |
9dbc240f TT |
299 | } |
300 | EXPORT_SYMBOL_GPL(svc_xprt_copy_addrs); | |
301 | ||
0f0257ea TT |
302 | /** |
303 | * svc_print_addr - Format rq_addr field for printing | |
304 | * @rqstp: svc_rqst struct containing address to print | |
305 | * @buf: target buffer for formatted address | |
306 | * @len: length of target buffer | |
307 | * | |
308 | */ | |
309 | char *svc_print_addr(struct svc_rqst *rqstp, char *buf, size_t len) | |
310 | { | |
311 | return __svc_print_addr(svc_addr(rqstp), buf, len); | |
312 | } | |
313 | EXPORT_SYMBOL_GPL(svc_print_addr); | |
314 | ||
9c335c0b BF |
315 | static bool svc_xprt_has_something_to_do(struct svc_xprt *xprt) |
316 | { | |
317 | if (xprt->xpt_flags & ((1<<XPT_CONN)|(1<<XPT_CLOSE))) | |
318 | return true; | |
319 | if (xprt->xpt_flags & ((1<<XPT_DATA)|(1<<XPT_DEFERRED))) | |
320 | return xprt->xpt_ops->xpo_has_wspace(xprt); | |
321 | return false; | |
322 | } | |
323 | ||
0971374e | 324 | static void svc_xprt_do_enqueue(struct svc_xprt *xprt) |
0f0257ea | 325 | { |
0f0257ea | 326 | struct svc_pool *pool; |
83a712e0 | 327 | struct svc_rqst *rqstp = NULL; |
0f0257ea | 328 | int cpu; |
b1691bc0 | 329 | bool queued = false; |
0f0257ea | 330 | |
9c335c0b | 331 | if (!svc_xprt_has_something_to_do(xprt)) |
83a712e0 | 332 | goto out; |
0f0257ea | 333 | |
0f0257ea TT |
334 | /* Mark transport as busy. It will remain in this state until |
335 | * the provider calls svc_xprt_received. We update XPT_BUSY | |
336 | * atomically because it also guards against trying to enqueue | |
337 | * the transport twice. | |
338 | */ | |
339 | if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags)) { | |
340 | /* Don't enqueue transport while already enqueued */ | |
341 | dprintk("svc: transport %p busy, not enqueued\n", xprt); | |
83a712e0 | 342 | goto out; |
0f0257ea | 343 | } |
0f0257ea | 344 | |
0c0746d0 TM |
345 | cpu = get_cpu(); |
346 | pool = svc_pool_for_cpu(xprt->xpt_server, cpu); | |
0c0746d0 | 347 | |
403c7b44 | 348 | atomic_long_inc(&pool->sp_stats.packets); |
0c0746d0 | 349 | |
b1691bc0 JL |
350 | redo_search: |
351 | /* find a thread for this xprt */ | |
352 | rcu_read_lock(); | |
353 | list_for_each_entry_rcu(rqstp, &pool->sp_all_threads, rq_all) { | |
354 | /* Do a lockless check first */ | |
355 | if (test_bit(RQ_BUSY, &rqstp->rq_flags)) | |
356 | continue; | |
357 | ||
358 | /* | |
359 | * Once the xprt has been queued, it can only be dequeued by | |
360 | * the task that intends to service it. All we can do at that | |
361 | * point is to try to wake this thread back up so that it can | |
362 | * do so. | |
983c6844 | 363 | */ |
b1691bc0 JL |
364 | if (!queued) { |
365 | spin_lock_bh(&rqstp->rq_lock); | |
366 | if (test_and_set_bit(RQ_BUSY, &rqstp->rq_flags)) { | |
367 | /* already busy, move on... */ | |
368 | spin_unlock_bh(&rqstp->rq_lock); | |
369 | continue; | |
370 | } | |
371 | ||
372 | /* this one will do */ | |
373 | rqstp->rq_xprt = xprt; | |
374 | svc_xprt_get(xprt); | |
375 | spin_unlock_bh(&rqstp->rq_lock); | |
376 | } | |
377 | rcu_read_unlock(); | |
378 | ||
403c7b44 | 379 | atomic_long_inc(&pool->sp_stats.threads_woken); |
b1691bc0 JL |
380 | wake_up_process(rqstp->rq_task); |
381 | put_cpu(); | |
83a712e0 | 382 | goto out; |
b1691bc0 JL |
383 | } |
384 | rcu_read_unlock(); | |
385 | ||
386 | /* | |
387 | * We didn't find an idle thread to use, so we need to queue the xprt. | |
388 | * Do so and then search again. If we find one, we can't hook this one | |
389 | * up to it directly but we can wake the thread up in the hopes that it | |
390 | * will pick it up once it searches for a xprt to service. | |
391 | */ | |
392 | if (!queued) { | |
393 | queued = true; | |
0f0257ea | 394 | dprintk("svc: transport %p put into queue\n", xprt); |
b1691bc0 | 395 | spin_lock_bh(&pool->sp_lock); |
0f0257ea | 396 | list_add_tail(&xprt->xpt_ready, &pool->sp_sockets); |
03cf6c9f | 397 | pool->sp_stats.sockets_queued++; |
b1691bc0 JL |
398 | spin_unlock_bh(&pool->sp_lock); |
399 | goto redo_search; | |
0f0257ea | 400 | } |
83a712e0 | 401 | rqstp = NULL; |
983c6844 | 402 | put_cpu(); |
83a712e0 JL |
403 | out: |
404 | trace_svc_xprt_do_enqueue(xprt, rqstp); | |
0f0257ea | 405 | } |
0971374e TM |
406 | |
407 | /* | |
408 | * Queue up a transport with data pending. If there are idle nfsd | |
409 | * processes, wake 'em up. | |
410 | * | |
411 | */ | |
412 | void svc_xprt_enqueue(struct svc_xprt *xprt) | |
413 | { | |
414 | if (test_bit(XPT_BUSY, &xprt->xpt_flags)) | |
415 | return; | |
416 | svc_xprt_do_enqueue(xprt); | |
417 | } | |
0f0257ea TT |
418 | EXPORT_SYMBOL_GPL(svc_xprt_enqueue); |
419 | ||
420 | /* | |
b1691bc0 | 421 | * Dequeue the first transport, if there is one. |
0f0257ea TT |
422 | */ |
423 | static struct svc_xprt *svc_xprt_dequeue(struct svc_pool *pool) | |
424 | { | |
b1691bc0 | 425 | struct svc_xprt *xprt = NULL; |
0f0257ea TT |
426 | |
427 | if (list_empty(&pool->sp_sockets)) | |
83a712e0 | 428 | goto out; |
0f0257ea | 429 | |
b1691bc0 JL |
430 | spin_lock_bh(&pool->sp_lock); |
431 | if (likely(!list_empty(&pool->sp_sockets))) { | |
432 | xprt = list_first_entry(&pool->sp_sockets, | |
433 | struct svc_xprt, xpt_ready); | |
434 | list_del_init(&xprt->xpt_ready); | |
435 | svc_xprt_get(xprt); | |
0f0257ea | 436 | |
b1691bc0 JL |
437 | dprintk("svc: transport %p dequeued, inuse=%d\n", |
438 | xprt, atomic_read(&xprt->xpt_ref.refcount)); | |
439 | } | |
440 | spin_unlock_bh(&pool->sp_lock); | |
83a712e0 JL |
441 | out: |
442 | trace_svc_xprt_dequeue(xprt); | |
0f0257ea TT |
443 | return xprt; |
444 | } | |
445 | ||
0f0257ea TT |
446 | /** |
447 | * svc_reserve - change the space reserved for the reply to a request. | |
448 | * @rqstp: The request in question | |
449 | * @space: new max space to reserve | |
450 | * | |
451 | * Each request reserves some space on the output queue of the transport | |
452 | * to make sure the reply fits. This function reduces that reserved | |
453 | * space to be the amount of space used already, plus @space. | |
454 | * | |
455 | */ | |
456 | void svc_reserve(struct svc_rqst *rqstp, int space) | |
457 | { | |
458 | space += rqstp->rq_res.head[0].iov_len; | |
459 | ||
460 | if (space < rqstp->rq_reserved) { | |
461 | struct svc_xprt *xprt = rqstp->rq_xprt; | |
462 | atomic_sub((rqstp->rq_reserved - space), &xprt->xpt_reserved); | |
463 | rqstp->rq_reserved = space; | |
464 | ||
51877680 TM |
465 | if (xprt->xpt_ops->xpo_adjust_wspace) |
466 | xprt->xpt_ops->xpo_adjust_wspace(xprt); | |
0f0257ea TT |
467 | svc_xprt_enqueue(xprt); |
468 | } | |
469 | } | |
24c3767e | 470 | EXPORT_SYMBOL_GPL(svc_reserve); |
0f0257ea TT |
471 | |
472 | static void svc_xprt_release(struct svc_rqst *rqstp) | |
473 | { | |
474 | struct svc_xprt *xprt = rqstp->rq_xprt; | |
475 | ||
476 | rqstp->rq_xprt->xpt_ops->xpo_release_rqst(rqstp); | |
477 | ||
2779e3ae TT |
478 | kfree(rqstp->rq_deferred); |
479 | rqstp->rq_deferred = NULL; | |
480 | ||
0f0257ea TT |
481 | svc_free_res_pages(rqstp); |
482 | rqstp->rq_res.page_len = 0; | |
483 | rqstp->rq_res.page_base = 0; | |
484 | ||
485 | /* Reset response buffer and release | |
486 | * the reservation. | |
487 | * But first, check that enough space was reserved | |
488 | * for the reply, otherwise we have a bug! | |
489 | */ | |
490 | if ((rqstp->rq_res.len) > rqstp->rq_reserved) | |
491 | printk(KERN_ERR "RPC request reserved %d but used %d\n", | |
492 | rqstp->rq_reserved, | |
493 | rqstp->rq_res.len); | |
494 | ||
495 | rqstp->rq_res.head[0].iov_len = 0; | |
496 | svc_reserve(rqstp, 0); | |
497 | rqstp->rq_xprt = NULL; | |
498 | ||
499 | svc_xprt_put(xprt); | |
500 | } | |
501 | ||
502 | /* | |
ceff739c JL |
503 | * Some svc_serv's will have occasional work to do, even when a xprt is not |
504 | * waiting to be serviced. This function is there to "kick" a task in one of | |
505 | * those services so that it can wake up and do that work. Note that we only | |
506 | * bother with pool 0 as we don't need to wake up more than one thread for | |
507 | * this purpose. | |
0f0257ea TT |
508 | */ |
509 | void svc_wake_up(struct svc_serv *serv) | |
510 | { | |
511 | struct svc_rqst *rqstp; | |
0f0257ea TT |
512 | struct svc_pool *pool; |
513 | ||
ceff739c JL |
514 | pool = &serv->sv_pools[0]; |
515 | ||
b1691bc0 JL |
516 | rcu_read_lock(); |
517 | list_for_each_entry_rcu(rqstp, &pool->sp_all_threads, rq_all) { | |
518 | /* skip any that aren't queued */ | |
519 | if (test_bit(RQ_BUSY, &rqstp->rq_flags)) | |
520 | continue; | |
521 | rcu_read_unlock(); | |
ceff739c JL |
522 | dprintk("svc: daemon %p woken up.\n", rqstp); |
523 | wake_up_process(rqstp->rq_task); | |
83a712e0 | 524 | trace_svc_wake_up(rqstp->rq_task->pid); |
b1691bc0 JL |
525 | return; |
526 | } | |
527 | rcu_read_unlock(); | |
528 | ||
529 | /* No free entries available */ | |
530 | set_bit(SP_TASK_PENDING, &pool->sp_flags); | |
531 | smp_wmb(); | |
83a712e0 | 532 | trace_svc_wake_up(0); |
0f0257ea | 533 | } |
24c3767e | 534 | EXPORT_SYMBOL_GPL(svc_wake_up); |
0f0257ea TT |
535 | |
536 | int svc_port_is_privileged(struct sockaddr *sin) | |
537 | { | |
538 | switch (sin->sa_family) { | |
539 | case AF_INET: | |
540 | return ntohs(((struct sockaddr_in *)sin)->sin_port) | |
541 | < PROT_SOCK; | |
542 | case AF_INET6: | |
543 | return ntohs(((struct sockaddr_in6 *)sin)->sin6_port) | |
544 | < PROT_SOCK; | |
545 | default: | |
546 | return 0; | |
547 | } | |
548 | } | |
549 | ||
550 | /* | |
c9233eb7 JL |
551 | * Make sure that we don't have too many active connections. If we have, |
552 | * something must be dropped. It's not clear what will happen if we allow | |
553 | * "too many" connections, but when dealing with network-facing software, | |
554 | * we have to code defensively. Here we do that by imposing hard limits. | |
0f0257ea TT |
555 | * |
556 | * There's no point in trying to do random drop here for DoS | |
557 | * prevention. The NFS clients does 1 reconnect in 15 seconds. An | |
558 | * attacker can easily beat that. | |
559 | * | |
560 | * The only somewhat efficient mechanism would be if drop old | |
561 | * connections from the same IP first. But right now we don't even | |
562 | * record the client IP in svc_sock. | |
c9233eb7 JL |
563 | * |
564 | * single-threaded services that expect a lot of clients will probably | |
565 | * need to set sv_maxconn to override the default value which is based | |
566 | * on the number of threads | |
0f0257ea TT |
567 | */ |
568 | static void svc_check_conn_limits(struct svc_serv *serv) | |
569 | { | |
c9233eb7 JL |
570 | unsigned int limit = serv->sv_maxconn ? serv->sv_maxconn : |
571 | (serv->sv_nrthreads+3) * 20; | |
572 | ||
573 | if (serv->sv_tmpcnt > limit) { | |
0f0257ea TT |
574 | struct svc_xprt *xprt = NULL; |
575 | spin_lock_bh(&serv->sv_lock); | |
576 | if (!list_empty(&serv->sv_tempsocks)) { | |
e87cc472 JP |
577 | /* Try to help the admin */ |
578 | net_notice_ratelimited("%s: too many open connections, consider increasing the %s\n", | |
579 | serv->sv_name, serv->sv_maxconn ? | |
580 | "max number of connections" : | |
581 | "number of threads"); | |
0f0257ea TT |
582 | /* |
583 | * Always select the oldest connection. It's not fair, | |
584 | * but so is life | |
585 | */ | |
586 | xprt = list_entry(serv->sv_tempsocks.prev, | |
587 | struct svc_xprt, | |
588 | xpt_list); | |
589 | set_bit(XPT_CLOSE, &xprt->xpt_flags); | |
590 | svc_xprt_get(xprt); | |
591 | } | |
592 | spin_unlock_bh(&serv->sv_lock); | |
593 | ||
594 | if (xprt) { | |
595 | svc_xprt_enqueue(xprt); | |
596 | svc_xprt_put(xprt); | |
597 | } | |
598 | } | |
599 | } | |
600 | ||
e1d83ee6 | 601 | static int svc_alloc_arg(struct svc_rqst *rqstp) |
0f0257ea | 602 | { |
6797fa5a BF |
603 | struct svc_serv *serv = rqstp->rq_server; |
604 | struct xdr_buf *arg; | |
605 | int pages; | |
606 | int i; | |
0f0257ea TT |
607 | |
608 | /* now allocate needed pages. If we get a failure, sleep briefly */ | |
609 | pages = (serv->sv_max_mesg + PAGE_SIZE) / PAGE_SIZE; | |
b25cd058 WAA |
610 | WARN_ON_ONCE(pages >= RPCSVC_MAXPAGES); |
611 | if (pages >= RPCSVC_MAXPAGES) | |
612 | /* use as many pages as possible */ | |
613 | pages = RPCSVC_MAXPAGES - 1; | |
0f0257ea TT |
614 | for (i = 0; i < pages ; i++) |
615 | while (rqstp->rq_pages[i] == NULL) { | |
616 | struct page *p = alloc_page(GFP_KERNEL); | |
617 | if (!p) { | |
7b54fe61 JL |
618 | set_current_state(TASK_INTERRUPTIBLE); |
619 | if (signalled() || kthread_should_stop()) { | |
620 | set_current_state(TASK_RUNNING); | |
7086721f | 621 | return -EINTR; |
7b54fe61 JL |
622 | } |
623 | schedule_timeout(msecs_to_jiffies(500)); | |
0f0257ea TT |
624 | } |
625 | rqstp->rq_pages[i] = p; | |
626 | } | |
2825a7f9 | 627 | rqstp->rq_page_end = &rqstp->rq_pages[i]; |
0f0257ea | 628 | rqstp->rq_pages[i++] = NULL; /* this might be seen in nfs_read_actor */ |
0f0257ea TT |
629 | |
630 | /* Make arg->head point to first page and arg->pages point to rest */ | |
631 | arg = &rqstp->rq_arg; | |
632 | arg->head[0].iov_base = page_address(rqstp->rq_pages[0]); | |
633 | arg->head[0].iov_len = PAGE_SIZE; | |
634 | arg->pages = rqstp->rq_pages + 1; | |
635 | arg->page_base = 0; | |
636 | /* save at least one page for response */ | |
637 | arg->page_len = (pages-2)*PAGE_SIZE; | |
638 | arg->len = (pages-1)*PAGE_SIZE; | |
639 | arg->tail[0].iov_len = 0; | |
6797fa5a BF |
640 | return 0; |
641 | } | |
0f0257ea | 642 | |
b1691bc0 JL |
643 | static bool |
644 | rqst_should_sleep(struct svc_rqst *rqstp) | |
645 | { | |
646 | struct svc_pool *pool = rqstp->rq_pool; | |
647 | ||
648 | /* did someone call svc_wake_up? */ | |
649 | if (test_and_clear_bit(SP_TASK_PENDING, &pool->sp_flags)) | |
650 | return false; | |
651 | ||
652 | /* was a socket queued? */ | |
653 | if (!list_empty(&pool->sp_sockets)) | |
654 | return false; | |
655 | ||
656 | /* are we shutting down? */ | |
657 | if (signalled() || kthread_should_stop()) | |
658 | return false; | |
659 | ||
660 | /* are we freezing? */ | |
661 | if (freezing(current)) | |
662 | return false; | |
663 | ||
664 | return true; | |
665 | } | |
666 | ||
e1d83ee6 | 667 | static struct svc_xprt *svc_get_next_xprt(struct svc_rqst *rqstp, long timeout) |
6797fa5a BF |
668 | { |
669 | struct svc_xprt *xprt; | |
670 | struct svc_pool *pool = rqstp->rq_pool; | |
a4aa8054 | 671 | long time_left = 0; |
0f0257ea | 672 | |
b1691bc0 JL |
673 | /* rq_xprt should be clear on entry */ |
674 | WARN_ON_ONCE(rqstp->rq_xprt); | |
675 | ||
f16b6e8d N |
676 | /* Normally we will wait up to 5 seconds for any required |
677 | * cache information to be provided. | |
678 | */ | |
679 | rqstp->rq_chandle.thread_wait = 5*HZ; | |
680 | ||
0f0257ea TT |
681 | xprt = svc_xprt_dequeue(pool); |
682 | if (xprt) { | |
683 | rqstp->rq_xprt = xprt; | |
f16b6e8d N |
684 | |
685 | /* As there is a shortage of threads and this request | |
6610f720 | 686 | * had to be queued, don't allow the thread to wait so |
f16b6e8d N |
687 | * long for cache updates. |
688 | */ | |
689 | rqstp->rq_chandle.thread_wait = 1*HZ; | |
4d5db3f5 | 690 | clear_bit(SP_TASK_PENDING, &pool->sp_flags); |
b1691bc0 JL |
691 | return xprt; |
692 | } | |
7086721f | 693 | |
b1691bc0 JL |
694 | /* |
695 | * We have to be able to interrupt this wait | |
696 | * to bring down the daemons ... | |
697 | */ | |
698 | set_current_state(TASK_INTERRUPTIBLE); | |
699 | clear_bit(RQ_BUSY, &rqstp->rq_flags); | |
700 | smp_mb(); | |
0f0257ea | 701 | |
b1691bc0 JL |
702 | if (likely(rqst_should_sleep(rqstp))) |
703 | time_left = schedule_timeout(timeout); | |
704 | else | |
705 | __set_current_state(TASK_RUNNING); | |
0f0257ea | 706 | |
b1691bc0 | 707 | try_to_freeze(); |
0f0257ea | 708 | |
b1691bc0 JL |
709 | spin_lock_bh(&rqstp->rq_lock); |
710 | set_bit(RQ_BUSY, &rqstp->rq_flags); | |
711 | spin_unlock_bh(&rqstp->rq_lock); | |
106f359c | 712 | |
b1691bc0 JL |
713 | xprt = rqstp->rq_xprt; |
714 | if (xprt != NULL) | |
715 | return xprt; | |
716 | ||
717 | if (!time_left) | |
718 | atomic_long_inc(&pool->sp_stats.threads_timedout); | |
719 | ||
720 | if (signalled() || kthread_should_stop()) | |
721 | return ERR_PTR(-EINTR); | |
722 | return ERR_PTR(-EAGAIN); | |
6797fa5a BF |
723 | } |
724 | ||
e1d83ee6 | 725 | static void svc_add_new_temp_xprt(struct svc_serv *serv, struct svc_xprt *newxpt) |
65b2e665 BF |
726 | { |
727 | spin_lock_bh(&serv->sv_lock); | |
728 | set_bit(XPT_TEMP, &newxpt->xpt_flags); | |
729 | list_add(&newxpt->xpt_list, &serv->sv_tempsocks); | |
730 | serv->sv_tmpcnt++; | |
731 | if (serv->sv_temptimer.function == NULL) { | |
732 | /* setup timer to age temp transports */ | |
733 | setup_timer(&serv->sv_temptimer, svc_age_temp_xprts, | |
734 | (unsigned long)serv); | |
735 | mod_timer(&serv->sv_temptimer, | |
736 | jiffies + svc_conn_age_period * HZ); | |
737 | } | |
738 | spin_unlock_bh(&serv->sv_lock); | |
739 | svc_xprt_received(newxpt); | |
740 | } | |
741 | ||
6797fa5a BF |
742 | static int svc_handle_xprt(struct svc_rqst *rqstp, struct svc_xprt *xprt) |
743 | { | |
744 | struct svc_serv *serv = rqstp->rq_server; | |
745 | int len = 0; | |
0f0257ea | 746 | |
1b644b6e BF |
747 | if (test_bit(XPT_CLOSE, &xprt->xpt_flags)) { |
748 | dprintk("svc_recv: found XPT_CLOSE\n"); | |
749 | svc_delete_xprt(xprt); | |
ca7896cd | 750 | /* Leave XPT_BUSY set on the dead xprt: */ |
83a712e0 | 751 | goto out; |
ca7896cd BF |
752 | } |
753 | if (test_bit(XPT_LISTENER, &xprt->xpt_flags)) { | |
0f0257ea | 754 | struct svc_xprt *newxpt; |
65b2e665 BF |
755 | /* |
756 | * We know this module_get will succeed because the | |
757 | * listener holds a reference too | |
758 | */ | |
759 | __module_get(xprt->xpt_class->xcl_owner); | |
760 | svc_check_conn_limits(xprt->xpt_server); | |
0f0257ea | 761 | newxpt = xprt->xpt_ops->xpo_accept(xprt); |
65b2e665 BF |
762 | if (newxpt) |
763 | svc_add_new_temp_xprt(serv, newxpt); | |
c789102c TM |
764 | else |
765 | module_put(xprt->xpt_class->xcl_owner); | |
9e5b208d | 766 | } else { |
6797fa5a | 767 | /* XPT_DATA|XPT_DEFERRED case: */ |
0f0257ea | 768 | dprintk("svc: server %p, pool %u, transport %p, inuse=%d\n", |
6797fa5a | 769 | rqstp, rqstp->rq_pool->sp_id, xprt, |
0f0257ea TT |
770 | atomic_read(&xprt->xpt_ref.refcount)); |
771 | rqstp->rq_deferred = svc_deferred_dequeue(xprt); | |
ca7896cd | 772 | if (rqstp->rq_deferred) |
0f0257ea | 773 | len = svc_deferred_recv(rqstp); |
ca7896cd | 774 | else |
0f0257ea TT |
775 | len = xprt->xpt_ops->xpo_recvfrom(rqstp); |
776 | dprintk("svc: got len=%d\n", len); | |
d10f27a7 BF |
777 | rqstp->rq_reserved = serv->sv_max_mesg; |
778 | atomic_add(rqstp->rq_reserved, &xprt->xpt_reserved); | |
0f0257ea | 779 | } |
6797fa5a | 780 | /* clear XPT_BUSY: */ |
ca7896cd | 781 | svc_xprt_received(xprt); |
83a712e0 JL |
782 | out: |
783 | trace_svc_handle_xprt(xprt, len); | |
6797fa5a BF |
784 | return len; |
785 | } | |
786 | ||
787 | /* | |
788 | * Receive the next request on any transport. This code is carefully | |
789 | * organised not to touch any cachelines in the shared svc_serv | |
790 | * structure, only cachelines in the local svc_pool. | |
791 | */ | |
792 | int svc_recv(struct svc_rqst *rqstp, long timeout) | |
793 | { | |
794 | struct svc_xprt *xprt = NULL; | |
795 | struct svc_serv *serv = rqstp->rq_server; | |
796 | int len, err; | |
797 | ||
798 | dprintk("svc: server %p waiting for data (to = %ld)\n", | |
799 | rqstp, timeout); | |
800 | ||
801 | if (rqstp->rq_xprt) | |
802 | printk(KERN_ERR | |
803 | "svc_recv: service %p, transport not NULL!\n", | |
804 | rqstp); | |
983c6844 | 805 | |
6797fa5a BF |
806 | err = svc_alloc_arg(rqstp); |
807 | if (err) | |
860a0d9e | 808 | goto out; |
6797fa5a BF |
809 | |
810 | try_to_freeze(); | |
811 | cond_resched(); | |
860a0d9e | 812 | err = -EINTR; |
6797fa5a | 813 | if (signalled() || kthread_should_stop()) |
860a0d9e | 814 | goto out; |
6797fa5a BF |
815 | |
816 | xprt = svc_get_next_xprt(rqstp, timeout); | |
860a0d9e JL |
817 | if (IS_ERR(xprt)) { |
818 | err = PTR_ERR(xprt); | |
819 | goto out; | |
820 | } | |
6797fa5a BF |
821 | |
822 | len = svc_handle_xprt(rqstp, xprt); | |
0f0257ea TT |
823 | |
824 | /* No data, incomplete (TCP) read, or accept() */ | |
860a0d9e | 825 | err = -EAGAIN; |
9f9d2ebe | 826 | if (len <= 0) |
860a0d9e | 827 | goto out_release; |
ca7896cd | 828 | |
0f0257ea TT |
829 | clear_bit(XPT_OLD, &xprt->xpt_flags); |
830 | ||
4d152e2c JL |
831 | if (xprt->xpt_ops->xpo_secure_port(rqstp)) |
832 | set_bit(RQ_SECURE, &rqstp->rq_flags); | |
833 | else | |
834 | clear_bit(RQ_SECURE, &rqstp->rq_flags); | |
0f0257ea | 835 | rqstp->rq_chandle.defer = svc_defer; |
860a0d9e | 836 | rqstp->rq_xid = svc_getu32(&rqstp->rq_arg.head[0]); |
0f0257ea TT |
837 | |
838 | if (serv->sv_stats) | |
839 | serv->sv_stats->netcnt++; | |
860a0d9e | 840 | trace_svc_recv(rqstp, len); |
0f0257ea | 841 | return len; |
860a0d9e | 842 | out_release: |
ca7896cd BF |
843 | rqstp->rq_res.len = 0; |
844 | svc_xprt_release(rqstp); | |
860a0d9e JL |
845 | out: |
846 | trace_svc_recv(rqstp, err); | |
847 | return err; | |
0f0257ea | 848 | } |
24c3767e | 849 | EXPORT_SYMBOL_GPL(svc_recv); |
0f0257ea TT |
850 | |
851 | /* | |
852 | * Drop request | |
853 | */ | |
854 | void svc_drop(struct svc_rqst *rqstp) | |
855 | { | |
856 | dprintk("svc: xprt %p dropped request\n", rqstp->rq_xprt); | |
857 | svc_xprt_release(rqstp); | |
858 | } | |
24c3767e | 859 | EXPORT_SYMBOL_GPL(svc_drop); |
0f0257ea TT |
860 | |
861 | /* | |
862 | * Return reply to client. | |
863 | */ | |
864 | int svc_send(struct svc_rqst *rqstp) | |
865 | { | |
866 | struct svc_xprt *xprt; | |
860a0d9e | 867 | int len = -EFAULT; |
0f0257ea TT |
868 | struct xdr_buf *xb; |
869 | ||
870 | xprt = rqstp->rq_xprt; | |
871 | if (!xprt) | |
860a0d9e | 872 | goto out; |
0f0257ea TT |
873 | |
874 | /* release the receive skb before sending the reply */ | |
875 | rqstp->rq_xprt->xpt_ops->xpo_release_rqst(rqstp); | |
876 | ||
877 | /* calculate over-all length */ | |
878 | xb = &rqstp->rq_res; | |
879 | xb->len = xb->head[0].iov_len + | |
880 | xb->page_len + | |
881 | xb->tail[0].iov_len; | |
882 | ||
883 | /* Grab mutex to serialize outgoing data. */ | |
884 | mutex_lock(&xprt->xpt_mutex); | |
f06f00a2 BF |
885 | if (test_bit(XPT_DEAD, &xprt->xpt_flags) |
886 | || test_bit(XPT_CLOSE, &xprt->xpt_flags)) | |
0f0257ea TT |
887 | len = -ENOTCONN; |
888 | else | |
889 | len = xprt->xpt_ops->xpo_sendto(rqstp); | |
890 | mutex_unlock(&xprt->xpt_mutex); | |
4cfc7e60 | 891 | rpc_wake_up(&xprt->xpt_bc_pending); |
0f0257ea TT |
892 | svc_xprt_release(rqstp); |
893 | ||
894 | if (len == -ECONNREFUSED || len == -ENOTCONN || len == -EAGAIN) | |
860a0d9e JL |
895 | len = 0; |
896 | out: | |
897 | trace_svc_send(rqstp, len); | |
0f0257ea TT |
898 | return len; |
899 | } | |
900 | ||
901 | /* | |
902 | * Timer function to close old temporary transports, using | |
903 | * a mark-and-sweep algorithm. | |
904 | */ | |
905 | static void svc_age_temp_xprts(unsigned long closure) | |
906 | { | |
907 | struct svc_serv *serv = (struct svc_serv *)closure; | |
908 | struct svc_xprt *xprt; | |
909 | struct list_head *le, *next; | |
0f0257ea TT |
910 | |
911 | dprintk("svc_age_temp_xprts\n"); | |
912 | ||
913 | if (!spin_trylock_bh(&serv->sv_lock)) { | |
914 | /* busy, try again 1 sec later */ | |
915 | dprintk("svc_age_temp_xprts: busy\n"); | |
916 | mod_timer(&serv->sv_temptimer, jiffies + HZ); | |
917 | return; | |
918 | } | |
919 | ||
920 | list_for_each_safe(le, next, &serv->sv_tempsocks) { | |
921 | xprt = list_entry(le, struct svc_xprt, xpt_list); | |
922 | ||
923 | /* First time through, just mark it OLD. Second time | |
924 | * through, close it. */ | |
925 | if (!test_and_set_bit(XPT_OLD, &xprt->xpt_flags)) | |
926 | continue; | |
f64f9e71 JP |
927 | if (atomic_read(&xprt->xpt_ref.refcount) > 1 || |
928 | test_bit(XPT_BUSY, &xprt->xpt_flags)) | |
0f0257ea | 929 | continue; |
e75bafbf | 930 | list_del_init(le); |
0f0257ea | 931 | set_bit(XPT_CLOSE, &xprt->xpt_flags); |
0f0257ea TT |
932 | dprintk("queuing xprt %p for closing\n", xprt); |
933 | ||
934 | /* a thread will dequeue and close it soon */ | |
935 | svc_xprt_enqueue(xprt); | |
0f0257ea | 936 | } |
e75bafbf | 937 | spin_unlock_bh(&serv->sv_lock); |
0f0257ea TT |
938 | |
939 | mod_timer(&serv->sv_temptimer, jiffies + svc_conn_age_period * HZ); | |
940 | } | |
941 | ||
edc7a894 BF |
942 | static void call_xpt_users(struct svc_xprt *xprt) |
943 | { | |
944 | struct svc_xpt_user *u; | |
945 | ||
946 | spin_lock(&xprt->xpt_lock); | |
947 | while (!list_empty(&xprt->xpt_users)) { | |
948 | u = list_first_entry(&xprt->xpt_users, struct svc_xpt_user, list); | |
949 | list_del(&u->list); | |
950 | u->callback(u); | |
951 | } | |
952 | spin_unlock(&xprt->xpt_lock); | |
953 | } | |
954 | ||
0f0257ea TT |
955 | /* |
956 | * Remove a dead transport | |
957 | */ | |
7710ec36 | 958 | static void svc_delete_xprt(struct svc_xprt *xprt) |
0f0257ea TT |
959 | { |
960 | struct svc_serv *serv = xprt->xpt_server; | |
22945e4a TT |
961 | struct svc_deferred_req *dr; |
962 | ||
963 | /* Only do this once */ | |
964 | if (test_and_set_bit(XPT_DEAD, &xprt->xpt_flags)) | |
ac9303eb | 965 | BUG(); |
0f0257ea TT |
966 | |
967 | dprintk("svc: svc_delete_xprt(%p)\n", xprt); | |
968 | xprt->xpt_ops->xpo_detach(xprt); | |
969 | ||
970 | spin_lock_bh(&serv->sv_lock); | |
8d65ef76 | 971 | list_del_init(&xprt->xpt_list); |
01047298 | 972 | WARN_ON_ONCE(!list_empty(&xprt->xpt_ready)); |
22945e4a TT |
973 | if (test_bit(XPT_TEMP, &xprt->xpt_flags)) |
974 | serv->sv_tmpcnt--; | |
788e69e5 | 975 | spin_unlock_bh(&serv->sv_lock); |
22945e4a | 976 | |
ab1b18f7 | 977 | while ((dr = svc_deferred_dequeue(xprt)) != NULL) |
22945e4a | 978 | kfree(dr); |
22945e4a | 979 | |
edc7a894 | 980 | call_xpt_users(xprt); |
22945e4a | 981 | svc_xprt_put(xprt); |
0f0257ea TT |
982 | } |
983 | ||
984 | void svc_close_xprt(struct svc_xprt *xprt) | |
985 | { | |
986 | set_bit(XPT_CLOSE, &xprt->xpt_flags); | |
987 | if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags)) | |
988 | /* someone else will have to effect the close */ | |
989 | return; | |
b1763316 BF |
990 | /* |
991 | * We expect svc_close_xprt() to work even when no threads are | |
992 | * running (e.g., while configuring the server before starting | |
993 | * any threads), so if the transport isn't busy, we delete | |
994 | * it ourself: | |
995 | */ | |
0f0257ea | 996 | svc_delete_xprt(xprt); |
0f0257ea | 997 | } |
a217813f | 998 | EXPORT_SYMBOL_GPL(svc_close_xprt); |
0f0257ea | 999 | |
cc630d9f | 1000 | static int svc_close_list(struct svc_serv *serv, struct list_head *xprt_list, struct net *net) |
0f0257ea TT |
1001 | { |
1002 | struct svc_xprt *xprt; | |
cc630d9f | 1003 | int ret = 0; |
0f0257ea | 1004 | |
719f8bcc | 1005 | spin_lock(&serv->sv_lock); |
b4f36f88 | 1006 | list_for_each_entry(xprt, xprt_list, xpt_list) { |
7b147f1f SK |
1007 | if (xprt->xpt_net != net) |
1008 | continue; | |
cc630d9f | 1009 | ret++; |
0f0257ea | 1010 | set_bit(XPT_CLOSE, &xprt->xpt_flags); |
cc630d9f | 1011 | svc_xprt_enqueue(xprt); |
0f0257ea | 1012 | } |
719f8bcc | 1013 | spin_unlock(&serv->sv_lock); |
cc630d9f | 1014 | return ret; |
0f0257ea TT |
1015 | } |
1016 | ||
cc630d9f | 1017 | static struct svc_xprt *svc_dequeue_net(struct svc_serv *serv, struct net *net) |
0f0257ea | 1018 | { |
b4f36f88 | 1019 | struct svc_pool *pool; |
0f0257ea TT |
1020 | struct svc_xprt *xprt; |
1021 | struct svc_xprt *tmp; | |
b4f36f88 BF |
1022 | int i; |
1023 | ||
b4f36f88 BF |
1024 | for (i = 0; i < serv->sv_nrpools; i++) { |
1025 | pool = &serv->sv_pools[i]; | |
1026 | ||
1027 | spin_lock_bh(&pool->sp_lock); | |
6f513365 | 1028 | list_for_each_entry_safe(xprt, tmp, &pool->sp_sockets, xpt_ready) { |
7b147f1f SK |
1029 | if (xprt->xpt_net != net) |
1030 | continue; | |
b4f36f88 | 1031 | list_del_init(&xprt->xpt_ready); |
cc630d9f BF |
1032 | spin_unlock_bh(&pool->sp_lock); |
1033 | return xprt; | |
b4f36f88 BF |
1034 | } |
1035 | spin_unlock_bh(&pool->sp_lock); | |
1036 | } | |
cc630d9f | 1037 | return NULL; |
6f513365 SK |
1038 | } |
1039 | ||
cc630d9f | 1040 | static void svc_clean_up_xprts(struct svc_serv *serv, struct net *net) |
6f513365 SK |
1041 | { |
1042 | struct svc_xprt *xprt; | |
719f8bcc | 1043 | |
cc630d9f BF |
1044 | while ((xprt = svc_dequeue_net(serv, net))) { |
1045 | set_bit(XPT_CLOSE, &xprt->xpt_flags); | |
719f8bcc | 1046 | svc_delete_xprt(xprt); |
cc630d9f | 1047 | } |
3a22bf50 SK |
1048 | } |
1049 | ||
cc630d9f BF |
1050 | /* |
1051 | * Server threads may still be running (especially in the case where the | |
1052 | * service is still running in other network namespaces). | |
1053 | * | |
1054 | * So we shut down sockets the same way we would on a running server, by | |
1055 | * setting XPT_CLOSE, enqueuing, and letting a thread pick it up to do | |
1056 | * the close. In the case there are no such other threads, | |
1057 | * threads running, svc_clean_up_xprts() does a simple version of a | |
1058 | * server's main event loop, and in the case where there are other | |
1059 | * threads, we may need to wait a little while and then check again to | |
1060 | * see if they're done. | |
1061 | */ | |
7b147f1f | 1062 | void svc_close_net(struct svc_serv *serv, struct net *net) |
3a22bf50 | 1063 | { |
cc630d9f | 1064 | int delay = 0; |
6f513365 | 1065 | |
cc630d9f BF |
1066 | while (svc_close_list(serv, &serv->sv_permsocks, net) + |
1067 | svc_close_list(serv, &serv->sv_tempsocks, net)) { | |
1068 | ||
1069 | svc_clean_up_xprts(serv, net); | |
1070 | msleep(delay++); | |
1071 | } | |
0f0257ea TT |
1072 | } |
1073 | ||
1074 | /* | |
1075 | * Handle defer and revisit of requests | |
1076 | */ | |
1077 | ||
1078 | static void svc_revisit(struct cache_deferred_req *dreq, int too_many) | |
1079 | { | |
1080 | struct svc_deferred_req *dr = | |
1081 | container_of(dreq, struct svc_deferred_req, handle); | |
1082 | struct svc_xprt *xprt = dr->xprt; | |
1083 | ||
22945e4a TT |
1084 | spin_lock(&xprt->xpt_lock); |
1085 | set_bit(XPT_DEFERRED, &xprt->xpt_flags); | |
1086 | if (too_many || test_bit(XPT_DEAD, &xprt->xpt_flags)) { | |
1087 | spin_unlock(&xprt->xpt_lock); | |
1088 | dprintk("revisit canceled\n"); | |
0f0257ea TT |
1089 | svc_xprt_put(xprt); |
1090 | kfree(dr); | |
1091 | return; | |
1092 | } | |
1093 | dprintk("revisit queued\n"); | |
1094 | dr->xprt = NULL; | |
0f0257ea TT |
1095 | list_add(&dr->handle.recent, &xprt->xpt_deferred); |
1096 | spin_unlock(&xprt->xpt_lock); | |
0f0257ea TT |
1097 | svc_xprt_enqueue(xprt); |
1098 | svc_xprt_put(xprt); | |
1099 | } | |
1100 | ||
260c1d12 TT |
1101 | /* |
1102 | * Save the request off for later processing. The request buffer looks | |
1103 | * like this: | |
1104 | * | |
1105 | * <xprt-header><rpc-header><rpc-pagelist><rpc-tail> | |
1106 | * | |
1107 | * This code can only handle requests that consist of an xprt-header | |
1108 | * and rpc-header. | |
1109 | */ | |
0f0257ea TT |
1110 | static struct cache_deferred_req *svc_defer(struct cache_req *req) |
1111 | { | |
1112 | struct svc_rqst *rqstp = container_of(req, struct svc_rqst, rq_chandle); | |
0f0257ea TT |
1113 | struct svc_deferred_req *dr; |
1114 | ||
30660e04 | 1115 | if (rqstp->rq_arg.page_len || !test_bit(RQ_USEDEFERRAL, &rqstp->rq_flags)) |
0f0257ea TT |
1116 | return NULL; /* if more than a page, give up FIXME */ |
1117 | if (rqstp->rq_deferred) { | |
1118 | dr = rqstp->rq_deferred; | |
1119 | rqstp->rq_deferred = NULL; | |
1120 | } else { | |
260c1d12 TT |
1121 | size_t skip; |
1122 | size_t size; | |
0f0257ea | 1123 | /* FIXME maybe discard if size too large */ |
260c1d12 | 1124 | size = sizeof(struct svc_deferred_req) + rqstp->rq_arg.len; |
0f0257ea TT |
1125 | dr = kmalloc(size, GFP_KERNEL); |
1126 | if (dr == NULL) | |
1127 | return NULL; | |
1128 | ||
1129 | dr->handle.owner = rqstp->rq_server; | |
1130 | dr->prot = rqstp->rq_prot; | |
1131 | memcpy(&dr->addr, &rqstp->rq_addr, rqstp->rq_addrlen); | |
1132 | dr->addrlen = rqstp->rq_addrlen; | |
1133 | dr->daddr = rqstp->rq_daddr; | |
1134 | dr->argslen = rqstp->rq_arg.len >> 2; | |
260c1d12 TT |
1135 | dr->xprt_hlen = rqstp->rq_xprt_hlen; |
1136 | ||
1137 | /* back up head to the start of the buffer and copy */ | |
1138 | skip = rqstp->rq_arg.len - rqstp->rq_arg.head[0].iov_len; | |
1139 | memcpy(dr->args, rqstp->rq_arg.head[0].iov_base - skip, | |
1140 | dr->argslen << 2); | |
0f0257ea TT |
1141 | } |
1142 | svc_xprt_get(rqstp->rq_xprt); | |
1143 | dr->xprt = rqstp->rq_xprt; | |
78b65eb3 | 1144 | set_bit(RQ_DROPME, &rqstp->rq_flags); |
0f0257ea TT |
1145 | |
1146 | dr->handle.revisit = svc_revisit; | |
1147 | return &dr->handle; | |
1148 | } | |
1149 | ||
1150 | /* | |
1151 | * recv data from a deferred request into an active one | |
1152 | */ | |
1153 | static int svc_deferred_recv(struct svc_rqst *rqstp) | |
1154 | { | |
1155 | struct svc_deferred_req *dr = rqstp->rq_deferred; | |
1156 | ||
260c1d12 TT |
1157 | /* setup iov_base past transport header */ |
1158 | rqstp->rq_arg.head[0].iov_base = dr->args + (dr->xprt_hlen>>2); | |
1159 | /* The iov_len does not include the transport header bytes */ | |
1160 | rqstp->rq_arg.head[0].iov_len = (dr->argslen<<2) - dr->xprt_hlen; | |
0f0257ea | 1161 | rqstp->rq_arg.page_len = 0; |
260c1d12 TT |
1162 | /* The rq_arg.len includes the transport header bytes */ |
1163 | rqstp->rq_arg.len = dr->argslen<<2; | |
0f0257ea TT |
1164 | rqstp->rq_prot = dr->prot; |
1165 | memcpy(&rqstp->rq_addr, &dr->addr, dr->addrlen); | |
1166 | rqstp->rq_addrlen = dr->addrlen; | |
260c1d12 TT |
1167 | /* Save off transport header len in case we get deferred again */ |
1168 | rqstp->rq_xprt_hlen = dr->xprt_hlen; | |
0f0257ea TT |
1169 | rqstp->rq_daddr = dr->daddr; |
1170 | rqstp->rq_respages = rqstp->rq_pages; | |
260c1d12 | 1171 | return (dr->argslen<<2) - dr->xprt_hlen; |
0f0257ea TT |
1172 | } |
1173 | ||
1174 | ||
1175 | static struct svc_deferred_req *svc_deferred_dequeue(struct svc_xprt *xprt) | |
1176 | { | |
1177 | struct svc_deferred_req *dr = NULL; | |
1178 | ||
1179 | if (!test_bit(XPT_DEFERRED, &xprt->xpt_flags)) | |
1180 | return NULL; | |
1181 | spin_lock(&xprt->xpt_lock); | |
0f0257ea TT |
1182 | if (!list_empty(&xprt->xpt_deferred)) { |
1183 | dr = list_entry(xprt->xpt_deferred.next, | |
1184 | struct svc_deferred_req, | |
1185 | handle.recent); | |
1186 | list_del_init(&dr->handle.recent); | |
62bac4af BF |
1187 | } else |
1188 | clear_bit(XPT_DEFERRED, &xprt->xpt_flags); | |
0f0257ea TT |
1189 | spin_unlock(&xprt->xpt_lock); |
1190 | return dr; | |
1191 | } | |
7fcb98d5 | 1192 | |
156e6209 CL |
1193 | /** |
1194 | * svc_find_xprt - find an RPC transport instance | |
1195 | * @serv: pointer to svc_serv to search | |
1196 | * @xcl_name: C string containing transport's class name | |
4cb54ca2 | 1197 | * @net: owner net pointer |
156e6209 CL |
1198 | * @af: Address family of transport's local address |
1199 | * @port: transport's IP port number | |
1200 | * | |
7fcb98d5 TT |
1201 | * Return the transport instance pointer for the endpoint accepting |
1202 | * connections/peer traffic from the specified transport class, | |
1203 | * address family and port. | |
1204 | * | |
1205 | * Specifying 0 for the address family or port is effectively a | |
1206 | * wild-card, and will result in matching the first transport in the | |
1207 | * service's list that has a matching class name. | |
1208 | */ | |
156e6209 | 1209 | struct svc_xprt *svc_find_xprt(struct svc_serv *serv, const char *xcl_name, |
4cb54ca2 SK |
1210 | struct net *net, const sa_family_t af, |
1211 | const unsigned short port) | |
7fcb98d5 TT |
1212 | { |
1213 | struct svc_xprt *xprt; | |
1214 | struct svc_xprt *found = NULL; | |
1215 | ||
1216 | /* Sanity check the args */ | |
156e6209 | 1217 | if (serv == NULL || xcl_name == NULL) |
7fcb98d5 TT |
1218 | return found; |
1219 | ||
1220 | spin_lock_bh(&serv->sv_lock); | |
1221 | list_for_each_entry(xprt, &serv->sv_permsocks, xpt_list) { | |
4cb54ca2 SK |
1222 | if (xprt->xpt_net != net) |
1223 | continue; | |
7fcb98d5 TT |
1224 | if (strcmp(xprt->xpt_class->xcl_name, xcl_name)) |
1225 | continue; | |
1226 | if (af != AF_UNSPEC && af != xprt->xpt_local.ss_family) | |
1227 | continue; | |
156e6209 | 1228 | if (port != 0 && port != svc_xprt_local_port(xprt)) |
7fcb98d5 TT |
1229 | continue; |
1230 | found = xprt; | |
a217813f | 1231 | svc_xprt_get(xprt); |
7fcb98d5 TT |
1232 | break; |
1233 | } | |
1234 | spin_unlock_bh(&serv->sv_lock); | |
1235 | return found; | |
1236 | } | |
1237 | EXPORT_SYMBOL_GPL(svc_find_xprt); | |
9571af18 | 1238 | |
335c54bd CL |
1239 | static int svc_one_xprt_name(const struct svc_xprt *xprt, |
1240 | char *pos, int remaining) | |
1241 | { | |
1242 | int len; | |
1243 | ||
1244 | len = snprintf(pos, remaining, "%s %u\n", | |
1245 | xprt->xpt_class->xcl_name, | |
1246 | svc_xprt_local_port(xprt)); | |
1247 | if (len >= remaining) | |
1248 | return -ENAMETOOLONG; | |
1249 | return len; | |
1250 | } | |
1251 | ||
1252 | /** | |
1253 | * svc_xprt_names - format a buffer with a list of transport names | |
1254 | * @serv: pointer to an RPC service | |
1255 | * @buf: pointer to a buffer to be filled in | |
1256 | * @buflen: length of buffer to be filled in | |
1257 | * | |
1258 | * Fills in @buf with a string containing a list of transport names, | |
1259 | * each name terminated with '\n'. | |
1260 | * | |
1261 | * Returns positive length of the filled-in string on success; otherwise | |
1262 | * a negative errno value is returned if an error occurs. | |
9571af18 | 1263 | */ |
335c54bd | 1264 | int svc_xprt_names(struct svc_serv *serv, char *buf, const int buflen) |
9571af18 TT |
1265 | { |
1266 | struct svc_xprt *xprt; | |
335c54bd CL |
1267 | int len, totlen; |
1268 | char *pos; | |
9571af18 TT |
1269 | |
1270 | /* Sanity check args */ | |
1271 | if (!serv) | |
1272 | return 0; | |
1273 | ||
1274 | spin_lock_bh(&serv->sv_lock); | |
335c54bd CL |
1275 | |
1276 | pos = buf; | |
1277 | totlen = 0; | |
9571af18 | 1278 | list_for_each_entry(xprt, &serv->sv_permsocks, xpt_list) { |
335c54bd CL |
1279 | len = svc_one_xprt_name(xprt, pos, buflen - totlen); |
1280 | if (len < 0) { | |
1281 | *buf = '\0'; | |
1282 | totlen = len; | |
1283 | } | |
1284 | if (len <= 0) | |
9571af18 | 1285 | break; |
335c54bd CL |
1286 | |
1287 | pos += len; | |
9571af18 TT |
1288 | totlen += len; |
1289 | } | |
335c54bd | 1290 | |
9571af18 TT |
1291 | spin_unlock_bh(&serv->sv_lock); |
1292 | return totlen; | |
1293 | } | |
1294 | EXPORT_SYMBOL_GPL(svc_xprt_names); | |
03cf6c9f GB |
1295 | |
1296 | ||
1297 | /*----------------------------------------------------------------------------*/ | |
1298 | ||
1299 | static void *svc_pool_stats_start(struct seq_file *m, loff_t *pos) | |
1300 | { | |
1301 | unsigned int pidx = (unsigned int)*pos; | |
1302 | struct svc_serv *serv = m->private; | |
1303 | ||
1304 | dprintk("svc_pool_stats_start, *pidx=%u\n", pidx); | |
1305 | ||
03cf6c9f GB |
1306 | if (!pidx) |
1307 | return SEQ_START_TOKEN; | |
1308 | return (pidx > serv->sv_nrpools ? NULL : &serv->sv_pools[pidx-1]); | |
1309 | } | |
1310 | ||
1311 | static void *svc_pool_stats_next(struct seq_file *m, void *p, loff_t *pos) | |
1312 | { | |
1313 | struct svc_pool *pool = p; | |
1314 | struct svc_serv *serv = m->private; | |
1315 | ||
1316 | dprintk("svc_pool_stats_next, *pos=%llu\n", *pos); | |
1317 | ||
1318 | if (p == SEQ_START_TOKEN) { | |
1319 | pool = &serv->sv_pools[0]; | |
1320 | } else { | |
1321 | unsigned int pidx = (pool - &serv->sv_pools[0]); | |
1322 | if (pidx < serv->sv_nrpools-1) | |
1323 | pool = &serv->sv_pools[pidx+1]; | |
1324 | else | |
1325 | pool = NULL; | |
1326 | } | |
1327 | ++*pos; | |
1328 | return pool; | |
1329 | } | |
1330 | ||
1331 | static void svc_pool_stats_stop(struct seq_file *m, void *p) | |
1332 | { | |
03cf6c9f GB |
1333 | } |
1334 | ||
1335 | static int svc_pool_stats_show(struct seq_file *m, void *p) | |
1336 | { | |
1337 | struct svc_pool *pool = p; | |
1338 | ||
1339 | if (p == SEQ_START_TOKEN) { | |
78c210ef | 1340 | seq_puts(m, "# pool packets-arrived sockets-enqueued threads-woken threads-timedout\n"); |
03cf6c9f GB |
1341 | return 0; |
1342 | } | |
1343 | ||
78c210ef | 1344 | seq_printf(m, "%u %lu %lu %lu %lu\n", |
03cf6c9f | 1345 | pool->sp_id, |
403c7b44 | 1346 | (unsigned long)atomic_long_read(&pool->sp_stats.packets), |
03cf6c9f | 1347 | pool->sp_stats.sockets_queued, |
403c7b44 JL |
1348 | (unsigned long)atomic_long_read(&pool->sp_stats.threads_woken), |
1349 | (unsigned long)atomic_long_read(&pool->sp_stats.threads_timedout)); | |
03cf6c9f GB |
1350 | |
1351 | return 0; | |
1352 | } | |
1353 | ||
1354 | static const struct seq_operations svc_pool_stats_seq_ops = { | |
1355 | .start = svc_pool_stats_start, | |
1356 | .next = svc_pool_stats_next, | |
1357 | .stop = svc_pool_stats_stop, | |
1358 | .show = svc_pool_stats_show, | |
1359 | }; | |
1360 | ||
1361 | int svc_pool_stats_open(struct svc_serv *serv, struct file *file) | |
1362 | { | |
1363 | int err; | |
1364 | ||
1365 | err = seq_open(file, &svc_pool_stats_seq_ops); | |
1366 | if (!err) | |
1367 | ((struct seq_file *) file->private_data)->private = serv; | |
1368 | return err; | |
1369 | } | |
1370 | EXPORT_SYMBOL(svc_pool_stats_open); | |
1371 | ||
1372 | /*----------------------------------------------------------------------------*/ |