2 * linux/fs/nfsd/nfs4callback.c
4 * Copyright (c) 2001 The Regents of the University of Michigan.
7 * Kendrick Smith <kmsmith@umich.edu>
8 * Andy Adamson <andros@umich.edu>
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. Neither the name of the University nor the names of its
20 * contributors may be used to endorse or promote products derived
21 * from this software without specific prior written permission.
23 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
24 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
25 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
26 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
28 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
30 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
31 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 #include <linux/module.h>
37 #include <linux/list.h>
38 #include <linux/inet.h>
39 #include <linux/errno.h>
40 #include <linux/delay.h>
41 #include <linux/sched.h>
42 #include <linux/kthread.h>
43 #include <linux/sunrpc/xdr.h>
44 #include <linux/sunrpc/svc.h>
45 #include <linux/sunrpc/clnt.h>
46 #include <linux/sunrpc/svcsock.h>
47 #include <linux/nfsd/nfsd.h>
48 #include <linux/nfsd/state.h>
49 #include <linux/sunrpc/sched.h>
50 #include <linux/nfs4.h>
52 #define NFSDDBG_FACILITY NFSDDBG_PROC
54 #define NFSPROC4_CB_NULL 0
55 #define NFSPROC4_CB_COMPOUND 1
56 #define NFS4_STATEID_SIZE 16
58 /* Index of predefined Linux callback client operations */
61 NFSPROC4_CLNT_CB_NULL = 0,
62 NFSPROC4_CLNT_CB_RECALL,
63 NFSPROC4_CLNT_CB_SEQUENCE,
71 #define NFS4_MAXTAGLEN 20
73 #define NFS4_enc_cb_null_sz 0
74 #define NFS4_dec_cb_null_sz 0
75 #define cb_compound_enc_hdr_sz 4
76 #define cb_compound_dec_hdr_sz (3 + (NFS4_MAXTAGLEN >> 2))
77 #define sessionid_sz (NFS4_MAX_SESSIONID_LEN >> 2)
78 #define cb_sequence_enc_sz (sessionid_sz + 4 + \
79 1 /* no referring calls list yet */)
80 #define cb_sequence_dec_sz (op_dec_sz + sessionid_sz + 4)
84 #define enc_nfs4_fh_sz (1 + (NFS4_FHSIZE >> 2))
85 #define enc_stateid_sz (NFS4_STATEID_SIZE >> 2)
86 #define NFS4_enc_cb_recall_sz (cb_compound_enc_hdr_sz + \
87 cb_sequence_enc_sz + \
88 1 + enc_stateid_sz + \
91 #define NFS4_dec_cb_recall_sz (cb_compound_dec_hdr_sz + \
92 cb_sequence_dec_sz + \
95 struct nfs4_rpc_args {
97 struct nfsd4_cb_sequence args_seq;
101 * Generic encode routines from fs/nfs/nfs4xdr.c
103 static inline __be32 *
104 xdr_writemem(__be32 *p, const void *ptr, int nbytes)
106 int tmp = XDR_QUADLEN(nbytes);
110 memcpy(p, ptr, nbytes);
114 #define WRITE32(n) *p++ = htonl(n)
115 #define WRITEMEM(ptr,nbytes) do { \
116 p = xdr_writemem(p, ptr, nbytes); \
118 #define RESERVE_SPACE(nbytes) do { \
119 p = xdr_reserve_space(xdr, nbytes); \
120 if (!p) dprintk("NFSD: RESERVE_SPACE(%d) failed in function %s\n", (int) (nbytes), __func__); \
125 * Generic decode routines from fs/nfs/nfs4xdr.c
127 #define DECODE_TAIL \
132 dprintk("NFSD: xdr error! (%s:%d)\n", __FILE__, __LINE__); \
136 #define READ32(x) (x) = ntohl(*p++)
137 #define READ64(x) do { \
138 (x) = (u64)ntohl(*p++) << 32; \
139 (x) |= ntohl(*p++); \
141 #define READTIME(x) do { \
143 (x.tv_sec) = ntohl(*p++); \
144 (x.tv_nsec) = ntohl(*p++); \
146 #define READ_BUF(nbytes) do { \
147 p = xdr_inline_decode(xdr, nbytes); \
149 dprintk("NFSD: %s: reply buffer overflowed in line %d.\n", \
150 __func__, __LINE__); \
155 struct nfs4_cb_compound_hdr {
157 u32 ident; /* minorversion 0 only */
170 } nfs_cb_errtbl[] = {
172 { NFS4ERR_PERM, EPERM },
173 { NFS4ERR_NOENT, ENOENT },
175 { NFS4ERR_NXIO, ENXIO },
176 { NFS4ERR_ACCESS, EACCES },
177 { NFS4ERR_EXIST, EEXIST },
178 { NFS4ERR_XDEV, EXDEV },
179 { NFS4ERR_NOTDIR, ENOTDIR },
180 { NFS4ERR_ISDIR, EISDIR },
181 { NFS4ERR_INVAL, EINVAL },
182 { NFS4ERR_FBIG, EFBIG },
183 { NFS4ERR_NOSPC, ENOSPC },
184 { NFS4ERR_ROFS, EROFS },
185 { NFS4ERR_MLINK, EMLINK },
186 { NFS4ERR_NAMETOOLONG, ENAMETOOLONG },
187 { NFS4ERR_NOTEMPTY, ENOTEMPTY },
188 { NFS4ERR_DQUOT, EDQUOT },
189 { NFS4ERR_STALE, ESTALE },
190 { NFS4ERR_BADHANDLE, EBADHANDLE },
191 { NFS4ERR_BAD_COOKIE, EBADCOOKIE },
192 { NFS4ERR_NOTSUPP, ENOTSUPP },
193 { NFS4ERR_TOOSMALL, ETOOSMALL },
194 { NFS4ERR_SERVERFAULT, ESERVERFAULT },
195 { NFS4ERR_BADTYPE, EBADTYPE },
196 { NFS4ERR_LOCKED, EAGAIN },
197 { NFS4ERR_RESOURCE, EREMOTEIO },
198 { NFS4ERR_SYMLINK, ELOOP },
199 { NFS4ERR_OP_ILLEGAL, EOPNOTSUPP },
200 { NFS4ERR_DEADLOCK, EDEADLK },
205 nfs_cb_stat_to_errno(int stat)
208 for (i = 0; nfs_cb_errtbl[i].stat != -1; i++) {
209 if (nfs_cb_errtbl[i].stat == stat)
210 return nfs_cb_errtbl[i].errno;
212 /* If we cannot translate the error, the recovery routines should
214 * Note: remaining NFSv4 error codes have values > 10000, so should
215 * not conflict with native Linux error codes.
225 encode_cb_compound_hdr(struct xdr_stream *xdr, struct nfs4_cb_compound_hdr *hdr)
230 WRITE32(0); /* tag length is always 0 */
231 WRITE32(hdr->minorversion);
237 static void encode_cb_nops(struct nfs4_cb_compound_hdr *hdr)
239 *hdr->nops_p = htonl(hdr->nops);
243 encode_cb_recall(struct xdr_stream *xdr, struct nfs4_delegation *dp,
244 struct nfs4_cb_compound_hdr *hdr)
247 int len = dp->dl_fh.fh_size;
249 RESERVE_SPACE(12+sizeof(dp->dl_stateid) + len);
250 WRITE32(OP_CB_RECALL);
251 WRITE32(dp->dl_stateid.si_generation);
252 WRITEMEM(&dp->dl_stateid.si_opaque, sizeof(stateid_opaque_t));
253 WRITE32(0); /* truncate optimization not implemented */
255 WRITEMEM(&dp->dl_fh.fh_base, len);
260 nfs4_xdr_enc_cb_null(struct rpc_rqst *req, __be32 *p)
262 struct xdr_stream xdrs, *xdr = &xdrs;
264 xdr_init_encode(&xdrs, &req->rq_snd_buf, p);
270 nfs4_xdr_enc_cb_recall(struct rpc_rqst *req, __be32 *p, struct nfs4_delegation *args)
272 struct xdr_stream xdr;
273 struct nfs4_cb_compound_hdr hdr = {
274 .ident = args->dl_ident,
277 xdr_init_encode(&xdr, &req->rq_snd_buf, p);
278 encode_cb_compound_hdr(&xdr, &hdr);
279 encode_cb_recall(&xdr, args, &hdr);
280 encode_cb_nops(&hdr);
286 decode_cb_compound_hdr(struct xdr_stream *xdr, struct nfs4_cb_compound_hdr *hdr){
292 READ_BUF(hdr->taglen + 4);
293 hdr->tag = (char *)p;
294 p += XDR_QUADLEN(hdr->taglen);
300 decode_cb_op_hdr(struct xdr_stream *xdr, enum nfs_opnum4 expected)
308 if (op != expected) {
309 dprintk("NFSD: decode_cb_op_hdr: Callback server returned "
310 " operation %d but we issued a request for %d\n",
315 if (nfserr != NFS_OK)
316 return -nfs_cb_stat_to_errno(nfserr);
321 nfs4_xdr_dec_cb_null(struct rpc_rqst *req, __be32 *p)
327 nfs4_xdr_dec_cb_recall(struct rpc_rqst *rqstp, __be32 *p)
329 struct xdr_stream xdr;
330 struct nfs4_cb_compound_hdr hdr;
333 xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p);
334 status = decode_cb_compound_hdr(&xdr, &hdr);
337 status = decode_cb_op_hdr(&xdr, OP_CB_RECALL);
343 * RPC procedure tables
345 #define PROC(proc, call, argtype, restype) \
346 [NFSPROC4_CLNT_##proc] = { \
347 .p_proc = NFSPROC4_CB_##call, \
348 .p_encode = (kxdrproc_t) nfs4_xdr_##argtype, \
349 .p_decode = (kxdrproc_t) nfs4_xdr_##restype, \
350 .p_arglen = NFS4_##argtype##_sz, \
351 .p_replen = NFS4_##restype##_sz, \
352 .p_statidx = NFSPROC4_CB_##call, \
356 static struct rpc_procinfo nfs4_cb_procedures[] = {
357 PROC(CB_NULL, NULL, enc_cb_null, dec_cb_null),
358 PROC(CB_RECALL, COMPOUND, enc_cb_recall, dec_cb_recall),
361 static struct rpc_version nfs_cb_version4 = {
363 .nrprocs = ARRAY_SIZE(nfs4_cb_procedures),
364 .procs = nfs4_cb_procedures
367 static struct rpc_version * nfs_cb_version[] = {
372 static struct rpc_program cb_program;
374 static struct rpc_stat cb_stats = {
375 .program = &cb_program
378 #define NFS4_CALLBACK 0x40000000
379 static struct rpc_program cb_program = {
381 .number = NFS4_CALLBACK,
382 .nrvers = ARRAY_SIZE(nfs_cb_version),
383 .version = nfs_cb_version,
385 .pipe_dir_name = "/nfsd4_cb",
388 static int max_cb_time(void)
390 return max(NFSD_LEASE_TIME/10, (time_t)1) * HZ;
393 /* Reference counting, callback cleanup, etc., all look racy as heck.
394 * And why is cb_set an atomic? */
396 int setup_callback_client(struct nfs4_client *clp)
398 struct nfs4_cb_conn *cb = &clp->cl_cb_conn;
399 struct rpc_timeout timeparms = {
400 .to_initval = max_cb_time(),
403 struct rpc_create_args args = {
404 .protocol = IPPROTO_TCP,
405 .address = (struct sockaddr *) &cb->cb_addr,
406 .addrsize = cb->cb_addrlen,
407 .timeout = &timeparms,
408 .program = &cb_program,
409 .prognumber = cb->cb_prog,
410 .version = nfs_cb_version[1]->number,
411 .authflavor = clp->cl_flavor,
412 .flags = (RPC_CLNT_CREATE_NOPING | RPC_CLNT_CREATE_QUIET),
413 .client_name = clp->cl_principal,
415 struct rpc_clnt *client;
417 if (!clp->cl_principal && (clp->cl_flavor >= RPC_AUTH_GSS_KRB5))
420 /* Create RPC client */
421 client = rpc_create(&args);
422 if (IS_ERR(client)) {
423 dprintk("NFSD: couldn't create callback client: %ld\n",
425 return PTR_ERR(client);
427 cb->cb_client = client;
432 static void warn_no_callback_path(struct nfs4_client *clp, int reason)
434 dprintk("NFSD: warning: no callback path to client %.*s: error %d\n",
435 (int)clp->cl_name.len, clp->cl_name.data, reason);
438 static void nfsd4_cb_probe_done(struct rpc_task *task, void *calldata)
440 struct nfs4_client *clp = calldata;
443 warn_no_callback_path(clp, task->tk_status);
445 atomic_set(&clp->cl_cb_conn.cb_set, 1);
446 put_nfs4_client(clp);
449 static const struct rpc_call_ops nfsd4_cb_probe_ops = {
450 .rpc_call_done = nfsd4_cb_probe_done,
453 static struct rpc_cred *callback_cred;
455 int set_callback_cred(void)
457 callback_cred = rpc_lookup_machine_cred();
464 void do_probe_callback(struct nfs4_client *clp)
466 struct nfs4_cb_conn *cb = &clp->cl_cb_conn;
467 struct rpc_message msg = {
468 .rpc_proc = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_NULL],
470 .rpc_cred = callback_cred
474 status = rpc_call_async(cb->cb_client, &msg, RPC_TASK_SOFT,
475 &nfsd4_cb_probe_ops, (void *)clp);
477 warn_no_callback_path(clp, status);
478 put_nfs4_client(clp);
483 * Set up the callback client and put a NFSPROC4_CB_NULL on the wire...
486 nfsd4_probe_callback(struct nfs4_client *clp)
490 BUG_ON(atomic_read(&clp->cl_cb_conn.cb_set));
492 status = setup_callback_client(clp);
494 warn_no_callback_path(clp, status);
498 /* the task holds a reference to the nfs4_client struct */
499 atomic_inc(&clp->cl_count);
501 do_probe_callback(clp);
505 * There's currently a single callback channel slot.
506 * If the slot is available, then mark it busy. Otherwise, set the
507 * thread for sleeping on the callback RPC wait queue.
509 static int nfsd41_cb_setup_sequence(struct nfs4_client *clp,
510 struct rpc_task *task)
512 struct nfs4_rpc_args *args = task->tk_msg.rpc_argp;
513 u32 *ptr = (u32 *)clp->cl_sessionid.data;
516 dprintk("%s: %u:%u:%u:%u\n", __func__,
517 ptr[0], ptr[1], ptr[2], ptr[3]);
519 if (test_and_set_bit(0, &clp->cl_cb_slot_busy) != 0) {
520 rpc_sleep_on(&clp->cl_cb_waitq, task, NULL);
521 dprintk("%s slot is busy\n", __func__);
527 * We'll need the clp during XDR encoding and decoding,
528 * and the sequence during decoding to verify the reply
530 args->args_seq.cbs_clp = clp;
531 task->tk_msg.rpc_resp = &args->args_seq;
534 dprintk("%s status=%d\n", __func__, status);
539 * TODO: cb_sequence should support referring call lists, cachethis, multiple
540 * slots, and mark callback channel down on communication errors.
542 static void nfsd4_cb_prepare(struct rpc_task *task, void *calldata)
544 struct nfs4_delegation *dp = calldata;
545 struct nfs4_client *clp = dp->dl_client;
546 struct nfs4_rpc_args *args = task->tk_msg.rpc_argp;
547 u32 minorversion = clp->cl_cb_conn.cb_minorversion;
550 args->args_seq.cbs_minorversion = minorversion;
552 status = nfsd41_cb_setup_sequence(clp, task);
554 if (status != -EAGAIN) {
555 /* terminate rpc task */
556 task->tk_status = status;
557 task->tk_action = NULL;
562 rpc_call_start(task);
565 static void nfsd4_cb_recall_done(struct rpc_task *task, void *calldata)
567 struct nfs4_delegation *dp = calldata;
568 struct nfs4_client *clp = dp->dl_client;
570 switch (task->tk_status) {
572 /* Network partition? */
573 atomic_set(&clp->cl_cb_conn.cb_set, 0);
574 warn_no_callback_path(clp, task->tk_status);
576 case -NFS4ERR_BAD_STATEID:
577 /* Race: client probably got cb_recall
578 * before open reply granting delegation */
581 /* success, or error we can't handle */
584 if (dp->dl_retries--) {
585 rpc_delay(task, 2*HZ);
587 rpc_restart_call(task);
589 atomic_set(&clp->cl_cb_conn.cb_set, 0);
590 warn_no_callback_path(clp, task->tk_status);
594 static void nfsd4_cb_recall_release(void *calldata)
596 struct nfs4_delegation *dp = calldata;
597 struct nfs4_client *clp = dp->dl_client;
599 nfs4_put_delegation(dp);
600 put_nfs4_client(clp);
603 static const struct rpc_call_ops nfsd4_cb_recall_ops = {
604 .rpc_call_prepare = nfsd4_cb_prepare,
605 .rpc_call_done = nfsd4_cb_recall_done,
606 .rpc_release = nfsd4_cb_recall_release,
610 * called with dp->dl_count inc'ed.
613 nfsd4_cb_recall(struct nfs4_delegation *dp)
615 struct nfs4_client *clp = dp->dl_client;
616 struct rpc_clnt *clnt = clp->cl_cb_conn.cb_client;
617 struct rpc_message msg = {
618 .rpc_proc = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_RECALL],
620 .rpc_cred = callback_cred
625 status = rpc_call_async(clnt, &msg, RPC_TASK_SOFT,
626 &nfsd4_cb_recall_ops, dp);
628 put_nfs4_client(clp);
629 nfs4_put_delegation(dp);