/* * linux/fs/nfsd/nfs4callback.c * * Copyright (c) 2001 The Regents of the University of Michigan. * All rights reserved. * * Kendrick Smith * Andy Adamson * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define NFSDDBG_FACILITY NFSDDBG_PROC #define NFSPROC4_CB_NULL 0 #define NFSPROC4_CB_COMPOUND 1 /* Index of predefined Linux callback client operations */ enum { NFSPROC4_CLNT_CB_NULL = 0, NFSPROC4_CLNT_CB_RECALL, }; enum nfs_cb_opnum4 { OP_CB_RECALL = 4, }; #define NFS4_MAXTAGLEN 20 #define NFS4_enc_cb_null_sz 0 #define NFS4_dec_cb_null_sz 0 #define cb_compound_enc_hdr_sz 4 #define cb_compound_dec_hdr_sz (3 + (NFS4_MAXTAGLEN >> 2)) #define op_enc_sz 1 #define op_dec_sz 2 #define enc_nfs4_fh_sz (1 + (NFS4_FHSIZE >> 2)) #define enc_stateid_sz (NFS4_STATEID_SIZE >> 2) #define NFS4_enc_cb_recall_sz (cb_compound_enc_hdr_sz + \ 1 + enc_stateid_sz + \ enc_nfs4_fh_sz) #define NFS4_dec_cb_recall_sz (cb_compound_dec_hdr_sz + \ op_dec_sz) /* * Generic encode routines from fs/nfs/nfs4xdr.c */ static inline __be32 * xdr_writemem(__be32 *p, const void *ptr, int nbytes) { int tmp = XDR_QUADLEN(nbytes); if (!tmp) return p; p[tmp-1] = 0; memcpy(p, ptr, nbytes); return p + tmp; } #define WRITE32(n) *p++ = htonl(n) #define WRITEMEM(ptr,nbytes) do { \ p = xdr_writemem(p, ptr, nbytes); \ } while (0) #define RESERVE_SPACE(nbytes) do { \ p = xdr_reserve_space(xdr, nbytes); \ if (!p) dprintk("NFSD: RESERVE_SPACE(%d) failed in function %s\n", (int) (nbytes), __func__); \ BUG_ON(!p); \ } while (0) /* * Generic decode routines from fs/nfs/nfs4xdr.c */ #define DECODE_TAIL \ status = 0; \ out: \ return status; \ xdr_error: \ dprintk("NFSD: xdr error! (%s:%d)\n", __FILE__, __LINE__); \ status = -EIO; \ goto out #define READ32(x) (x) = ntohl(*p++) #define READ64(x) do { \ (x) = (u64)ntohl(*p++) << 32; \ (x) |= ntohl(*p++); \ } while (0) #define READTIME(x) do { \ p++; \ (x.tv_sec) = ntohl(*p++); \ (x.tv_nsec) = ntohl(*p++); \ } while (0) #define READ_BUF(nbytes) do { \ p = xdr_inline_decode(xdr, nbytes); \ if (!p) { \ dprintk("NFSD: %s: reply buffer overflowed in line %d.\n", \ __func__, __LINE__); \ return -EIO; \ } \ } while (0) struct nfs4_cb_compound_hdr { int status; u32 ident; u32 nops; u32 taglen; char * tag; }; static struct { int stat; int errno; } nfs_cb_errtbl[] = { { NFS4_OK, 0 }, { NFS4ERR_PERM, EPERM }, { NFS4ERR_NOENT, ENOENT }, { NFS4ERR_IO, EIO }, { NFS4ERR_NXIO, ENXIO }, { NFS4ERR_ACCESS, EACCES }, { NFS4ERR_EXIST, EEXIST }, { NFS4ERR_XDEV, EXDEV }, { NFS4ERR_NOTDIR, ENOTDIR }, { NFS4ERR_ISDIR, EISDIR }, { NFS4ERR_INVAL, EINVAL }, { NFS4ERR_FBIG, EFBIG }, { NFS4ERR_NOSPC, ENOSPC }, { NFS4ERR_ROFS, EROFS }, { NFS4ERR_MLINK, EMLINK }, { NFS4ERR_NAMETOOLONG, ENAMETOOLONG }, { NFS4ERR_NOTEMPTY, ENOTEMPTY }, { NFS4ERR_DQUOT, EDQUOT }, { NFS4ERR_STALE, ESTALE }, { NFS4ERR_BADHANDLE, EBADHANDLE }, { NFS4ERR_BAD_COOKIE, EBADCOOKIE }, { NFS4ERR_NOTSUPP, ENOTSUPP }, { NFS4ERR_TOOSMALL, ETOOSMALL }, { NFS4ERR_SERVERFAULT, ESERVERFAULT }, { NFS4ERR_BADTYPE, EBADTYPE }, { NFS4ERR_LOCKED, EAGAIN }, { NFS4ERR_RESOURCE, EREMOTEIO }, { NFS4ERR_SYMLINK, ELOOP }, { NFS4ERR_OP_ILLEGAL, EOPNOTSUPP }, { NFS4ERR_DEADLOCK, EDEADLK }, { -1, EIO } }; static int nfs_cb_stat_to_errno(int stat) { int i; for (i = 0; nfs_cb_errtbl[i].stat != -1; i++) { if (nfs_cb_errtbl[i].stat == stat) return nfs_cb_errtbl[i].errno; } /* If we cannot translate the error, the recovery routines should * handle it. * Note: remaining NFSv4 error codes have values > 10000, so should * not conflict with native Linux error codes. */ return stat; } /* * XDR encode */ static int encode_cb_compound_hdr(struct xdr_stream *xdr, struct nfs4_cb_compound_hdr *hdr) { __be32 * p; RESERVE_SPACE(16); WRITE32(0); /* tag length is always 0 */ WRITE32(NFS4_MINOR_VERSION); WRITE32(hdr->ident); WRITE32(hdr->nops); return 0; } static int encode_cb_recall(struct xdr_stream *xdr, struct nfs4_cb_recall *cb_rec) { __be32 *p; int len = cb_rec->cbr_fh.fh_size; RESERVE_SPACE(12+sizeof(cb_rec->cbr_stateid) + len); WRITE32(OP_CB_RECALL); WRITE32(cb_rec->cbr_stateid.si_generation); WRITEMEM(&cb_rec->cbr_stateid.si_opaque, sizeof(stateid_opaque_t)); WRITE32(cb_rec->cbr_trunc); WRITE32(len); WRITEMEM(&cb_rec->cbr_fh.fh_base, len); return 0; } static int nfs4_xdr_enc_cb_null(struct rpc_rqst *req, __be32 *p) { struct xdr_stream xdrs, *xdr = &xdrs; xdr_init_encode(&xdrs, &req->rq_snd_buf, p); RESERVE_SPACE(0); return 0; } static int nfs4_xdr_enc_cb_recall(struct rpc_rqst *req, __be32 *p, struct nfs4_cb_recall *args) { struct xdr_stream xdr; struct nfs4_cb_compound_hdr hdr = { .ident = args->cbr_ident, .nops = 1, }; xdr_init_encode(&xdr, &req->rq_snd_buf, p); encode_cb_compound_hdr(&xdr, &hdr); return (encode_cb_recall(&xdr, args)); } static int decode_cb_compound_hdr(struct xdr_stream *xdr, struct nfs4_cb_compound_hdr *hdr){ __be32 *p; READ_BUF(8); READ32(hdr->status); READ32(hdr->taglen); READ_BUF(hdr->taglen + 4); hdr->tag = (char *)p; p += XDR_QUADLEN(hdr->taglen); READ32(hdr->nops); return 0; } static int decode_cb_op_hdr(struct xdr_stream *xdr, enum nfs_opnum4 expected) { __be32 *p; u32 op; int32_t nfserr; READ_BUF(8); READ32(op); if (op != expected) { dprintk("NFSD: decode_cb_op_hdr: Callback server returned " " operation %d but we issued a request for %d\n", op, expected); return -EIO; } READ32(nfserr); if (nfserr != NFS_OK) return -nfs_cb_stat_to_errno(nfserr); return 0; } static int nfs4_xdr_dec_cb_null(struct rpc_rqst *req, __be32 *p) { return 0; } static int nfs4_xdr_dec_cb_recall(struct rpc_rqst *rqstp, __be32 *p) { struct xdr_stream xdr; struct nfs4_cb_compound_hdr hdr; int status; xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p); status = decode_cb_compound_hdr(&xdr, &hdr); if (status) goto out; status = decode_cb_op_hdr(&xdr, OP_CB_RECALL); out: return status; } /* * RPC procedure tables */ #define PROC(proc, call, argtype, restype) \ [NFSPROC4_CLNT_##proc] = { \ .p_proc = NFSPROC4_CB_##call, \ .p_encode = (kxdrproc_t) nfs4_xdr_##argtype, \ .p_decode = (kxdrproc_t) nfs4_xdr_##restype, \ .p_arglen = NFS4_##argtype##_sz, \ .p_replen = NFS4_##restype##_sz, \ .p_statidx = NFSPROC4_CB_##call, \ .p_name = #proc, \ } static struct rpc_procinfo nfs4_cb_procedures[] = { PROC(CB_NULL, NULL, enc_cb_null, dec_cb_null), PROC(CB_RECALL, COMPOUND, enc_cb_recall, dec_cb_recall), }; static struct rpc_version nfs_cb_version4 = { .number = 1, .nrprocs = ARRAY_SIZE(nfs4_cb_procedures), .procs = nfs4_cb_procedures }; static struct rpc_version * nfs_cb_version[] = { NULL, &nfs_cb_version4, }; static struct rpc_program cb_program; static struct rpc_stat cb_stats = { .program = &cb_program }; #define NFS4_CALLBACK 0x40000000 static struct rpc_program cb_program = { .name = "nfs4_cb", .number = NFS4_CALLBACK, .nrvers = ARRAY_SIZE(nfs_cb_version), .version = nfs_cb_version, .stats = &cb_stats, .pipe_dir_name = "/nfsd4_cb", }; static int max_cb_time(void) { return max(NFSD_LEASE_TIME/10, (time_t)1) * HZ; } /* Reference counting, callback cleanup, etc., all look racy as heck. * And why is cb_set an atomic? */ int setup_callback_client(struct nfs4_client *clp) { struct sockaddr_in addr; struct nfs4_callback *cb = &clp->cl_callback; struct rpc_timeout timeparms = { .to_initval = max_cb_time(), .to_retries = 0, }; struct rpc_create_args args = { .protocol = IPPROTO_TCP, .address = (struct sockaddr *)&addr, .addrsize = sizeof(addr), .timeout = &timeparms, .program = &cb_program, .prognumber = cb->cb_prog, .version = nfs_cb_version[1]->number, .authflavor = clp->cl_flavor, .flags = (RPC_CLNT_CREATE_NOPING | RPC_CLNT_CREATE_QUIET), .client_name = clp->cl_principal, }; struct rpc_clnt *client; if (!clp->cl_principal && (clp->cl_flavor >= RPC_AUTH_GSS_KRB5)) return -EINVAL; /* Initialize address */ memset(&addr, 0, sizeof(addr)); addr.sin_family = AF_INET; addr.sin_port = htons(cb->cb_port); addr.sin_addr.s_addr = htonl(cb->cb_addr); /* Create RPC client */ client = rpc_create(&args); if (IS_ERR(client)) { dprintk("NFSD: couldn't create callback client: %ld\n", PTR_ERR(client)); return PTR_ERR(client); } cb->cb_client = client; return 0; } static int do_probe_callback(void *data) { struct nfs4_client *clp = data; struct nfs4_callback *cb = &clp->cl_callback; struct rpc_message msg = { .rpc_proc = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_NULL], .rpc_argp = clp, }; int status; status = setup_callback_client(clp); if (status) goto out_err; status = rpc_call_sync(cb->cb_client, &msg, RPC_TASK_SOFT); if (status) goto out_release_client; atomic_set(&cb->cb_set, 1); put_nfs4_client(clp); return 0; out_release_client: rpc_shutdown_client(cb->cb_client); cb->cb_client = NULL; out_err: dprintk("NFSD: warning: no callback path to client %.*s: error %d\n", (int)clp->cl_name.len, clp->cl_name.data, status); put_nfs4_client(clp); return 0; } /* * Set up the callback client and put a NFSPROC4_CB_NULL on the wire... */ void nfsd4_probe_callback(struct nfs4_client *clp) { struct task_struct *t; BUG_ON(atomic_read(&clp->cl_callback.cb_set)); /* the task holds a reference to the nfs4_client struct */ atomic_inc(&clp->cl_count); t = kthread_run(do_probe_callback, clp, "nfs4_cb_probe"); if (IS_ERR(t)) atomic_dec(&clp->cl_count); return; } /* * called with dp->dl_count inc'ed. */ void nfsd4_cb_recall(struct nfs4_delegation *dp) { struct nfs4_client *clp = dp->dl_client; struct rpc_clnt *clnt = clp->cl_callback.cb_client; struct nfs4_cb_recall *cbr = &dp->dl_recall; struct rpc_message msg = { .rpc_proc = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_RECALL], .rpc_argp = cbr, }; int retries = 1; int status = 0; cbr->cbr_trunc = 0; /* XXX need to implement truncate optimization */ cbr->cbr_dp = dp; status = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT); while (retries--) { switch (status) { case -EIO: /* Network partition? */ atomic_set(&clp->cl_callback.cb_set, 0); case -EBADHANDLE: case -NFS4ERR_BAD_STATEID: /* Race: client probably got cb_recall * before open reply granting delegation */ break; default: goto out_put_cred; } ssleep(2); status = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT); } out_put_cred: /* * Success or failure, now we're either waiting for lease expiration * or deleg_return. */ put_nfs4_client(clp); nfs4_put_delegation(dp); return; }