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/sunrpc/clnt.h>
37 #include <linux/nfsd/nfsd.h>
38 #include <linux/nfsd/state.h>
40 #define NFSDDBG_FACILITY NFSDDBG_PROC
42 #define NFSPROC4_CB_NULL 0
43 #define NFSPROC4_CB_COMPOUND 1
44 #define NFS4_STATEID_SIZE 16
46 /* Index of predefined Linux callback client operations */
49 NFSPROC4_CLNT_CB_NULL = 0,
50 NFSPROC4_CLNT_CB_RECALL,
51 NFSPROC4_CLNT_CB_SEQUENCE,
59 #define NFS4_MAXTAGLEN 20
61 #define NFS4_enc_cb_null_sz 0
62 #define NFS4_dec_cb_null_sz 0
63 #define cb_compound_enc_hdr_sz 4
64 #define cb_compound_dec_hdr_sz (3 + (NFS4_MAXTAGLEN >> 2))
65 #define sessionid_sz (NFS4_MAX_SESSIONID_LEN >> 2)
66 #define cb_sequence_enc_sz (sessionid_sz + 4 + \
67 1 /* no referring calls list yet */)
68 #define cb_sequence_dec_sz (op_dec_sz + sessionid_sz + 4)
72 #define enc_nfs4_fh_sz (1 + (NFS4_FHSIZE >> 2))
73 #define enc_stateid_sz (NFS4_STATEID_SIZE >> 2)
74 #define NFS4_enc_cb_recall_sz (cb_compound_enc_hdr_sz + \
75 cb_sequence_enc_sz + \
76 1 + enc_stateid_sz + \
79 #define NFS4_dec_cb_recall_sz (cb_compound_dec_hdr_sz + \
80 cb_sequence_dec_sz + \
83 struct nfs4_rpc_args {
85 struct nfsd4_cb_sequence args_seq;
89 * Generic encode routines from fs/nfs/nfs4xdr.c
91 static inline __be32 *
92 xdr_writemem(__be32 *p, const void *ptr, int nbytes)
94 int tmp = XDR_QUADLEN(nbytes);
98 memcpy(p, ptr, nbytes);
102 #define WRITE32(n) *p++ = htonl(n)
103 #define WRITEMEM(ptr,nbytes) do { \
104 p = xdr_writemem(p, ptr, nbytes); \
106 #define RESERVE_SPACE(nbytes) do { \
107 p = xdr_reserve_space(xdr, nbytes); \
108 if (!p) dprintk("NFSD: RESERVE_SPACE(%d) failed in function %s\n", (int) (nbytes), __func__); \
113 * Generic decode routines from fs/nfs/nfs4xdr.c
115 #define DECODE_TAIL \
120 dprintk("NFSD: xdr error! (%s:%d)\n", __FILE__, __LINE__); \
124 #define READ32(x) (x) = ntohl(*p++)
125 #define READ64(x) do { \
126 (x) = (u64)ntohl(*p++) << 32; \
127 (x) |= ntohl(*p++); \
129 #define READTIME(x) do { \
131 (x.tv_sec) = ntohl(*p++); \
132 (x.tv_nsec) = ntohl(*p++); \
134 #define READ_BUF(nbytes) do { \
135 p = xdr_inline_decode(xdr, nbytes); \
137 dprintk("NFSD: %s: reply buffer overflowed in line %d.\n", \
138 __func__, __LINE__); \
143 struct nfs4_cb_compound_hdr {
145 u32 ident; /* minorversion 0 only */
158 } nfs_cb_errtbl[] = {
160 { NFS4ERR_PERM, EPERM },
161 { NFS4ERR_NOENT, ENOENT },
163 { NFS4ERR_NXIO, ENXIO },
164 { NFS4ERR_ACCESS, EACCES },
165 { NFS4ERR_EXIST, EEXIST },
166 { NFS4ERR_XDEV, EXDEV },
167 { NFS4ERR_NOTDIR, ENOTDIR },
168 { NFS4ERR_ISDIR, EISDIR },
169 { NFS4ERR_INVAL, EINVAL },
170 { NFS4ERR_FBIG, EFBIG },
171 { NFS4ERR_NOSPC, ENOSPC },
172 { NFS4ERR_ROFS, EROFS },
173 { NFS4ERR_MLINK, EMLINK },
174 { NFS4ERR_NAMETOOLONG, ENAMETOOLONG },
175 { NFS4ERR_NOTEMPTY, ENOTEMPTY },
176 { NFS4ERR_DQUOT, EDQUOT },
177 { NFS4ERR_STALE, ESTALE },
178 { NFS4ERR_BADHANDLE, EBADHANDLE },
179 { NFS4ERR_BAD_COOKIE, EBADCOOKIE },
180 { NFS4ERR_NOTSUPP, ENOTSUPP },
181 { NFS4ERR_TOOSMALL, ETOOSMALL },
182 { NFS4ERR_SERVERFAULT, ESERVERFAULT },
183 { NFS4ERR_BADTYPE, EBADTYPE },
184 { NFS4ERR_LOCKED, EAGAIN },
185 { NFS4ERR_RESOURCE, EREMOTEIO },
186 { NFS4ERR_SYMLINK, ELOOP },
187 { NFS4ERR_OP_ILLEGAL, EOPNOTSUPP },
188 { NFS4ERR_DEADLOCK, EDEADLK },
193 nfs_cb_stat_to_errno(int stat)
196 for (i = 0; nfs_cb_errtbl[i].stat != -1; i++) {
197 if (nfs_cb_errtbl[i].stat == stat)
198 return nfs_cb_errtbl[i].errno;
200 /* If we cannot translate the error, the recovery routines should
202 * Note: remaining NFSv4 error codes have values > 10000, so should
203 * not conflict with native Linux error codes.
213 encode_cb_compound_hdr(struct xdr_stream *xdr, struct nfs4_cb_compound_hdr *hdr)
218 WRITE32(0); /* tag length is always 0 */
219 WRITE32(hdr->minorversion);
225 static void encode_cb_nops(struct nfs4_cb_compound_hdr *hdr)
227 *hdr->nops_p = htonl(hdr->nops);
231 encode_cb_recall(struct xdr_stream *xdr, struct nfs4_delegation *dp,
232 struct nfs4_cb_compound_hdr *hdr)
235 int len = dp->dl_fh.fh_size;
237 RESERVE_SPACE(12+sizeof(dp->dl_stateid) + len);
238 WRITE32(OP_CB_RECALL);
239 WRITE32(dp->dl_stateid.si_generation);
240 WRITEMEM(&dp->dl_stateid.si_opaque, sizeof(stateid_opaque_t));
241 WRITE32(0); /* truncate optimization not implemented */
243 WRITEMEM(&dp->dl_fh.fh_base, len);
248 encode_cb_sequence(struct xdr_stream *xdr, struct nfsd4_cb_sequence *args,
249 struct nfs4_cb_compound_hdr *hdr)
253 if (hdr->minorversion == 0)
256 RESERVE_SPACE(1 + NFS4_MAX_SESSIONID_LEN + 20);
258 WRITE32(OP_CB_SEQUENCE);
259 WRITEMEM(args->cbs_clp->cl_sessionid.data, NFS4_MAX_SESSIONID_LEN);
260 WRITE32(args->cbs_clp->cl_cb_seq_nr);
261 WRITE32(0); /* slotid, always 0 */
262 WRITE32(0); /* highest slotid always 0 */
263 WRITE32(0); /* cachethis always 0 */
264 WRITE32(0); /* FIXME: support referring_call_lists */
269 nfs4_xdr_enc_cb_null(struct rpc_rqst *req, __be32 *p)
271 struct xdr_stream xdrs, *xdr = &xdrs;
273 xdr_init_encode(&xdrs, &req->rq_snd_buf, p);
279 nfs4_xdr_enc_cb_recall(struct rpc_rqst *req, __be32 *p,
280 struct nfs4_rpc_args *rpc_args)
282 struct xdr_stream xdr;
283 struct nfs4_delegation *args = rpc_args->args_op;
284 struct nfs4_cb_compound_hdr hdr = {
285 .ident = args->dl_ident,
286 .minorversion = rpc_args->args_seq.cbs_minorversion,
289 xdr_init_encode(&xdr, &req->rq_snd_buf, p);
290 encode_cb_compound_hdr(&xdr, &hdr);
291 encode_cb_sequence(&xdr, &rpc_args->args_seq, &hdr);
292 encode_cb_recall(&xdr, args, &hdr);
293 encode_cb_nops(&hdr);
299 decode_cb_compound_hdr(struct xdr_stream *xdr, struct nfs4_cb_compound_hdr *hdr){
305 READ_BUF(hdr->taglen + 4);
306 hdr->tag = (char *)p;
307 p += XDR_QUADLEN(hdr->taglen);
313 decode_cb_op_hdr(struct xdr_stream *xdr, enum nfs_opnum4 expected)
321 if (op != expected) {
322 dprintk("NFSD: decode_cb_op_hdr: Callback server returned "
323 " operation %d but we issued a request for %d\n",
328 if (nfserr != NFS_OK)
329 return -nfs_cb_stat_to_errno(nfserr);
334 * Our current back channel implmentation supports a single backchannel
335 * with a single slot.
338 decode_cb_sequence(struct xdr_stream *xdr, struct nfsd4_cb_sequence *res,
339 struct rpc_rqst *rqstp)
341 struct nfs4_sessionid id;
346 if (res->cbs_minorversion == 0)
349 status = decode_cb_op_hdr(xdr, OP_CB_SEQUENCE);
354 * If the server returns different values for sessionID, slotID or
355 * sequence number, the server is looney tunes.
357 status = -ESERVERFAULT;
359 READ_BUF(NFS4_MAX_SESSIONID_LEN + 16);
360 memcpy(id.data, p, NFS4_MAX_SESSIONID_LEN);
361 p += XDR_QUADLEN(NFS4_MAX_SESSIONID_LEN);
362 if (memcmp(id.data, res->cbs_clp->cl_sessionid.data,
363 NFS4_MAX_SESSIONID_LEN)) {
364 dprintk("%s Invalid session id\n", __func__);
368 if (dummy != res->cbs_clp->cl_cb_seq_nr) {
369 dprintk("%s Invalid sequence number\n", __func__);
372 READ32(dummy); /* slotid must be 0 */
374 dprintk("%s Invalid slotid\n", __func__);
377 /* FIXME: process highest slotid and target highest slotid */
385 nfs4_xdr_dec_cb_null(struct rpc_rqst *req, __be32 *p)
391 nfs4_xdr_dec_cb_recall(struct rpc_rqst *rqstp, __be32 *p,
392 struct nfsd4_cb_sequence *seq)
394 struct xdr_stream xdr;
395 struct nfs4_cb_compound_hdr hdr;
398 xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p);
399 status = decode_cb_compound_hdr(&xdr, &hdr);
403 status = decode_cb_sequence(&xdr, seq, rqstp);
407 status = decode_cb_op_hdr(&xdr, OP_CB_RECALL);
413 * RPC procedure tables
415 #define PROC(proc, call, argtype, restype) \
416 [NFSPROC4_CLNT_##proc] = { \
417 .p_proc = NFSPROC4_CB_##call, \
418 .p_encode = (kxdrproc_t) nfs4_xdr_##argtype, \
419 .p_decode = (kxdrproc_t) nfs4_xdr_##restype, \
420 .p_arglen = NFS4_##argtype##_sz, \
421 .p_replen = NFS4_##restype##_sz, \
422 .p_statidx = NFSPROC4_CB_##call, \
426 static struct rpc_procinfo nfs4_cb_procedures[] = {
427 PROC(CB_NULL, NULL, enc_cb_null, dec_cb_null),
428 PROC(CB_RECALL, COMPOUND, enc_cb_recall, dec_cb_recall),
431 static struct rpc_version nfs_cb_version4 = {
433 .nrprocs = ARRAY_SIZE(nfs4_cb_procedures),
434 .procs = nfs4_cb_procedures
437 static struct rpc_version * nfs_cb_version[] = {
442 static struct rpc_program cb_program;
444 static struct rpc_stat cb_stats = {
445 .program = &cb_program
448 #define NFS4_CALLBACK 0x40000000
449 static struct rpc_program cb_program = {
451 .number = NFS4_CALLBACK,
452 .nrvers = ARRAY_SIZE(nfs_cb_version),
453 .version = nfs_cb_version,
455 .pipe_dir_name = "/nfsd4_cb",
458 static int max_cb_time(void)
460 return max(NFSD_LEASE_TIME/10, (time_t)1) * HZ;
463 /* Reference counting, callback cleanup, etc., all look racy as heck.
464 * And why is cb_set an atomic? */
466 int setup_callback_client(struct nfs4_client *clp)
468 struct nfs4_cb_conn *cb = &clp->cl_cb_conn;
469 struct rpc_timeout timeparms = {
470 .to_initval = max_cb_time(),
473 struct rpc_create_args args = {
474 .protocol = XPRT_TRANSPORT_TCP,
475 .address = (struct sockaddr *) &cb->cb_addr,
476 .addrsize = cb->cb_addrlen,
477 .timeout = &timeparms,
478 .program = &cb_program,
479 .prognumber = cb->cb_prog,
480 .version = nfs_cb_version[1]->number,
481 .authflavor = clp->cl_flavor,
482 .flags = (RPC_CLNT_CREATE_NOPING | RPC_CLNT_CREATE_QUIET),
483 .client_name = clp->cl_principal,
485 struct rpc_clnt *client;
487 if (!clp->cl_principal && (clp->cl_flavor >= RPC_AUTH_GSS_KRB5))
489 if (cb->cb_minorversion) {
490 args.bc_xprt = clp->cl_cb_xprt;
491 args.protocol = XPRT_TRANSPORT_BC_TCP;
493 /* Create RPC client */
494 client = rpc_create(&args);
495 if (IS_ERR(client)) {
496 dprintk("NFSD: couldn't create callback client: %ld\n",
498 return PTR_ERR(client);
500 cb->cb_client = client;
505 static void warn_no_callback_path(struct nfs4_client *clp, int reason)
507 dprintk("NFSD: warning: no callback path to client %.*s: error %d\n",
508 (int)clp->cl_name.len, clp->cl_name.data, reason);
511 static void nfsd4_cb_probe_done(struct rpc_task *task, void *calldata)
513 struct nfs4_client *clp = calldata;
516 warn_no_callback_path(clp, task->tk_status);
518 atomic_set(&clp->cl_cb_conn.cb_set, 1);
519 put_nfs4_client(clp);
522 static const struct rpc_call_ops nfsd4_cb_probe_ops = {
523 .rpc_call_done = nfsd4_cb_probe_done,
526 static struct rpc_cred *callback_cred;
528 int set_callback_cred(void)
530 callback_cred = rpc_lookup_machine_cred();
537 void do_probe_callback(struct nfs4_client *clp)
539 struct nfs4_cb_conn *cb = &clp->cl_cb_conn;
540 struct rpc_message msg = {
541 .rpc_proc = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_NULL],
543 .rpc_cred = callback_cred
547 status = rpc_call_async(cb->cb_client, &msg, RPC_TASK_SOFT,
548 &nfsd4_cb_probe_ops, (void *)clp);
550 warn_no_callback_path(clp, status);
551 put_nfs4_client(clp);
556 * Set up the callback client and put a NFSPROC4_CB_NULL on the wire...
559 nfsd4_probe_callback(struct nfs4_client *clp)
563 BUG_ON(atomic_read(&clp->cl_cb_conn.cb_set));
565 status = setup_callback_client(clp);
567 warn_no_callback_path(clp, status);
571 /* the task holds a reference to the nfs4_client struct */
572 atomic_inc(&clp->cl_count);
574 do_probe_callback(clp);
578 * There's currently a single callback channel slot.
579 * If the slot is available, then mark it busy. Otherwise, set the
580 * thread for sleeping on the callback RPC wait queue.
582 static int nfsd41_cb_setup_sequence(struct nfs4_client *clp,
583 struct rpc_task *task)
585 struct nfs4_rpc_args *args = task->tk_msg.rpc_argp;
586 u32 *ptr = (u32 *)clp->cl_sessionid.data;
589 dprintk("%s: %u:%u:%u:%u\n", __func__,
590 ptr[0], ptr[1], ptr[2], ptr[3]);
592 if (test_and_set_bit(0, &clp->cl_cb_slot_busy) != 0) {
593 rpc_sleep_on(&clp->cl_cb_waitq, task, NULL);
594 dprintk("%s slot is busy\n", __func__);
600 * We'll need the clp during XDR encoding and decoding,
601 * and the sequence during decoding to verify the reply
603 args->args_seq.cbs_clp = clp;
604 task->tk_msg.rpc_resp = &args->args_seq;
607 dprintk("%s status=%d\n", __func__, status);
612 * TODO: cb_sequence should support referring call lists, cachethis, multiple
613 * slots, and mark callback channel down on communication errors.
615 static void nfsd4_cb_prepare(struct rpc_task *task, void *calldata)
617 struct nfs4_delegation *dp = calldata;
618 struct nfs4_client *clp = dp->dl_client;
619 struct nfs4_rpc_args *args = task->tk_msg.rpc_argp;
620 u32 minorversion = clp->cl_cb_conn.cb_minorversion;
623 args->args_seq.cbs_minorversion = minorversion;
625 status = nfsd41_cb_setup_sequence(clp, task);
627 if (status != -EAGAIN) {
628 /* terminate rpc task */
629 task->tk_status = status;
630 task->tk_action = NULL;
635 rpc_call_start(task);
638 static void nfsd4_cb_done(struct rpc_task *task, void *calldata)
640 struct nfs4_delegation *dp = calldata;
641 struct nfs4_client *clp = dp->dl_client;
643 dprintk("%s: minorversion=%d\n", __func__,
644 clp->cl_cb_conn.cb_minorversion);
646 if (clp->cl_cb_conn.cb_minorversion) {
647 /* No need for lock, access serialized in nfsd4_cb_prepare */
649 clear_bit(0, &clp->cl_cb_slot_busy);
650 rpc_wake_up_next(&clp->cl_cb_waitq);
651 dprintk("%s: freed slot, new seqid=%d\n", __func__,
654 /* We're done looking into the sequence information */
655 task->tk_msg.rpc_resp = NULL;
659 static void nfsd4_cb_recall_done(struct rpc_task *task, void *calldata)
661 struct nfs4_delegation *dp = calldata;
662 struct nfs4_client *clp = dp->dl_client;
664 nfsd4_cb_done(task, calldata);
666 switch (task->tk_status) {
668 /* Network partition? */
669 atomic_set(&clp->cl_cb_conn.cb_set, 0);
670 warn_no_callback_path(clp, task->tk_status);
672 case -NFS4ERR_BAD_STATEID:
673 /* Race: client probably got cb_recall
674 * before open reply granting delegation */
677 /* success, or error we can't handle */
680 if (dp->dl_retries--) {
681 rpc_delay(task, 2*HZ);
683 rpc_restart_call(task);
686 atomic_set(&clp->cl_cb_conn.cb_set, 0);
687 warn_no_callback_path(clp, task->tk_status);
690 kfree(task->tk_msg.rpc_argp);
693 static void nfsd4_cb_recall_release(void *calldata)
695 struct nfs4_delegation *dp = calldata;
696 struct nfs4_client *clp = dp->dl_client;
698 nfs4_put_delegation(dp);
699 put_nfs4_client(clp);
702 static const struct rpc_call_ops nfsd4_cb_recall_ops = {
703 .rpc_call_prepare = nfsd4_cb_prepare,
704 .rpc_call_done = nfsd4_cb_recall_done,
705 .rpc_release = nfsd4_cb_recall_release,
709 * called with dp->dl_count inc'ed.
712 nfsd4_cb_recall(struct nfs4_delegation *dp)
714 struct nfs4_client *clp = dp->dl_client;
715 struct rpc_clnt *clnt = clp->cl_cb_conn.cb_client;
716 struct nfs4_rpc_args *args;
717 struct rpc_message msg = {
718 .rpc_proc = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_RECALL],
719 .rpc_cred = callback_cred
721 int status = -ENOMEM;
723 args = kzalloc(sizeof(*args), GFP_KERNEL);
729 status = rpc_call_async(clnt, &msg, RPC_TASK_SOFT,
730 &nfsd4_cb_recall_ops, dp);
734 put_nfs4_client(clp);
735 nfs4_put_delegation(dp);