v4.19.13 snapshot.
diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
new file mode 100644
index 0000000..601bf33
--- /dev/null
+++ b/fs/nfsd/nfs4callback.c
@@ -0,0 +1,1207 @@
+/*
+ * Copyright (c) 2001 The Regents of the University of Michigan.
+ * All rights reserved.
+ *
+ * Kendrick Smith <kmsmith@umich.edu>
+ * Andy Adamson <andros@umich.edu>
+ *
+ * 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 <linux/sunrpc/clnt.h>
+#include <linux/sunrpc/xprt.h>
+#include <linux/sunrpc/svc_xprt.h>
+#include <linux/slab.h>
+#include "nfsd.h"
+#include "state.h"
+#include "netns.h"
+#include "xdr4cb.h"
+
+#define NFSDDBG_FACILITY NFSDDBG_PROC
+
+static void nfsd4_mark_cb_fault(struct nfs4_client *, int reason);
+
+#define NFSPROC4_CB_NULL 0
+#define NFSPROC4_CB_COMPOUND 1
+
+/* Index of predefined Linux callback client operations */
+
+struct nfs4_cb_compound_hdr {
+ /* args */
+ u32 ident; /* minorversion 0 only */
+ u32 nops;
+ __be32 *nops_p;
+ u32 minorversion;
+ /* res */
+ int status;
+};
+
+/*
+ * Handle decode buffer overflows out-of-line.
+ */
+static void print_overflow_msg(const char *func, const struct xdr_stream *xdr)
+{
+ dprintk("NFS: %s prematurely hit the end of our receive buffer. "
+ "Remaining buffer length is %tu words.\n",
+ func, xdr->end - xdr->p);
+}
+
+static __be32 *xdr_encode_empty_array(__be32 *p)
+{
+ *p++ = xdr_zero;
+ return p;
+}
+
+/*
+ * Encode/decode NFSv4 CB basic data types
+ *
+ * Basic NFSv4 callback data types are defined in section 15 of RFC
+ * 3530: "Network File System (NFS) version 4 Protocol" and section
+ * 20 of RFC 5661: "Network File System (NFS) Version 4 Minor Version
+ * 1 Protocol"
+ */
+
+/*
+ * nfs_cb_opnum4
+ *
+ * enum nfs_cb_opnum4 {
+ * OP_CB_GETATTR = 3,
+ * ...
+ * };
+ */
+enum nfs_cb_opnum4 {
+ OP_CB_GETATTR = 3,
+ OP_CB_RECALL = 4,
+ OP_CB_LAYOUTRECALL = 5,
+ OP_CB_NOTIFY = 6,
+ OP_CB_PUSH_DELEG = 7,
+ OP_CB_RECALL_ANY = 8,
+ OP_CB_RECALLABLE_OBJ_AVAIL = 9,
+ OP_CB_RECALL_SLOT = 10,
+ OP_CB_SEQUENCE = 11,
+ OP_CB_WANTS_CANCELLED = 12,
+ OP_CB_NOTIFY_LOCK = 13,
+ OP_CB_NOTIFY_DEVICEID = 14,
+ OP_CB_ILLEGAL = 10044
+};
+
+static void encode_nfs_cb_opnum4(struct xdr_stream *xdr, enum nfs_cb_opnum4 op)
+{
+ __be32 *p;
+
+ p = xdr_reserve_space(xdr, 4);
+ *p = cpu_to_be32(op);
+}
+
+/*
+ * nfs_fh4
+ *
+ * typedef opaque nfs_fh4<NFS4_FHSIZE>;
+ */
+static void encode_nfs_fh4(struct xdr_stream *xdr, const struct knfsd_fh *fh)
+{
+ u32 length = fh->fh_size;
+ __be32 *p;
+
+ BUG_ON(length > NFS4_FHSIZE);
+ p = xdr_reserve_space(xdr, 4 + length);
+ xdr_encode_opaque(p, &fh->fh_base, length);
+}
+
+/*
+ * stateid4
+ *
+ * struct stateid4 {
+ * uint32_t seqid;
+ * opaque other[12];
+ * };
+ */
+static void encode_stateid4(struct xdr_stream *xdr, const stateid_t *sid)
+{
+ __be32 *p;
+
+ p = xdr_reserve_space(xdr, NFS4_STATEID_SIZE);
+ *p++ = cpu_to_be32(sid->si_generation);
+ xdr_encode_opaque_fixed(p, &sid->si_opaque, NFS4_STATEID_OTHER_SIZE);
+}
+
+/*
+ * sessionid4
+ *
+ * typedef opaque sessionid4[NFS4_SESSIONID_SIZE];
+ */
+static void encode_sessionid4(struct xdr_stream *xdr,
+ const struct nfsd4_session *session)
+{
+ __be32 *p;
+
+ p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN);
+ xdr_encode_opaque_fixed(p, session->se_sessionid.data,
+ NFS4_MAX_SESSIONID_LEN);
+}
+
+/*
+ * nfsstat4
+ */
+static const 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 }
+};
+
+/*
+ * 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.
+ */
+static int nfs_cb_stat_to_errno(int status)
+{
+ int i;
+
+ for (i = 0; nfs_cb_errtbl[i].stat != -1; i++) {
+ if (nfs_cb_errtbl[i].stat == status)
+ return nfs_cb_errtbl[i].errno;
+ }
+
+ dprintk("NFSD: Unrecognized NFS CB status value: %u\n", status);
+ return -status;
+}
+
+static int decode_cb_op_status(struct xdr_stream *xdr,
+ enum nfs_cb_opnum4 expected, int *status)
+{
+ __be32 *p;
+ u32 op;
+
+ p = xdr_inline_decode(xdr, 4 + 4);
+ if (unlikely(p == NULL))
+ goto out_overflow;
+ op = be32_to_cpup(p++);
+ if (unlikely(op != expected))
+ goto out_unexpected;
+ *status = nfs_cb_stat_to_errno(be32_to_cpup(p));
+ return 0;
+out_overflow:
+ print_overflow_msg(__func__, xdr);
+ return -EIO;
+out_unexpected:
+ dprintk("NFSD: Callback server returned operation %d but "
+ "we issued a request for %d\n", op, expected);
+ return -EIO;
+}
+
+/*
+ * CB_COMPOUND4args
+ *
+ * struct CB_COMPOUND4args {
+ * utf8str_cs tag;
+ * uint32_t minorversion;
+ * uint32_t callback_ident;
+ * nfs_cb_argop4 argarray<>;
+ * };
+*/
+static void encode_cb_compound4args(struct xdr_stream *xdr,
+ struct nfs4_cb_compound_hdr *hdr)
+{
+ __be32 * p;
+
+ p = xdr_reserve_space(xdr, 4 + 4 + 4 + 4);
+ p = xdr_encode_empty_array(p); /* empty tag */
+ *p++ = cpu_to_be32(hdr->minorversion);
+ *p++ = cpu_to_be32(hdr->ident);
+
+ hdr->nops_p = p;
+ *p = cpu_to_be32(hdr->nops); /* argarray element count */
+}
+
+/*
+ * Update argarray element count
+ */
+static void encode_cb_nops(struct nfs4_cb_compound_hdr *hdr)
+{
+ BUG_ON(hdr->nops > NFS4_MAX_BACK_CHANNEL_OPS);
+ *hdr->nops_p = cpu_to_be32(hdr->nops);
+}
+
+/*
+ * CB_COMPOUND4res
+ *
+ * struct CB_COMPOUND4res {
+ * nfsstat4 status;
+ * utf8str_cs tag;
+ * nfs_cb_resop4 resarray<>;
+ * };
+ */
+static int decode_cb_compound4res(struct xdr_stream *xdr,
+ struct nfs4_cb_compound_hdr *hdr)
+{
+ u32 length;
+ __be32 *p;
+
+ p = xdr_inline_decode(xdr, 4 + 4);
+ if (unlikely(p == NULL))
+ goto out_overflow;
+ hdr->status = be32_to_cpup(p++);
+ /* Ignore the tag */
+ length = be32_to_cpup(p++);
+ p = xdr_inline_decode(xdr, length + 4);
+ if (unlikely(p == NULL))
+ goto out_overflow;
+ p += XDR_QUADLEN(length);
+ hdr->nops = be32_to_cpup(p);
+ return 0;
+out_overflow:
+ print_overflow_msg(__func__, xdr);
+ return -EIO;
+}
+
+/*
+ * CB_RECALL4args
+ *
+ * struct CB_RECALL4args {
+ * stateid4 stateid;
+ * bool truncate;
+ * nfs_fh4 fh;
+ * };
+ */
+static void encode_cb_recall4args(struct xdr_stream *xdr,
+ const struct nfs4_delegation *dp,
+ struct nfs4_cb_compound_hdr *hdr)
+{
+ __be32 *p;
+
+ encode_nfs_cb_opnum4(xdr, OP_CB_RECALL);
+ encode_stateid4(xdr, &dp->dl_stid.sc_stateid);
+
+ p = xdr_reserve_space(xdr, 4);
+ *p++ = xdr_zero; /* truncate */
+
+ encode_nfs_fh4(xdr, &dp->dl_stid.sc_file->fi_fhandle);
+
+ hdr->nops++;
+}
+
+/*
+ * CB_SEQUENCE4args
+ *
+ * struct CB_SEQUENCE4args {
+ * sessionid4 csa_sessionid;
+ * sequenceid4 csa_sequenceid;
+ * slotid4 csa_slotid;
+ * slotid4 csa_highest_slotid;
+ * bool csa_cachethis;
+ * referring_call_list4 csa_referring_call_lists<>;
+ * };
+ */
+static void encode_cb_sequence4args(struct xdr_stream *xdr,
+ const struct nfsd4_callback *cb,
+ struct nfs4_cb_compound_hdr *hdr)
+{
+ struct nfsd4_session *session = cb->cb_clp->cl_cb_session;
+ __be32 *p;
+
+ if (hdr->minorversion == 0)
+ return;
+
+ encode_nfs_cb_opnum4(xdr, OP_CB_SEQUENCE);
+ encode_sessionid4(xdr, session);
+
+ p = xdr_reserve_space(xdr, 4 + 4 + 4 + 4 + 4);
+ *p++ = cpu_to_be32(session->se_cb_seq_nr); /* csa_sequenceid */
+ *p++ = xdr_zero; /* csa_slotid */
+ *p++ = xdr_zero; /* csa_highest_slotid */
+ *p++ = xdr_zero; /* csa_cachethis */
+ xdr_encode_empty_array(p); /* csa_referring_call_lists */
+
+ hdr->nops++;
+}
+
+/*
+ * CB_SEQUENCE4resok
+ *
+ * struct CB_SEQUENCE4resok {
+ * sessionid4 csr_sessionid;
+ * sequenceid4 csr_sequenceid;
+ * slotid4 csr_slotid;
+ * slotid4 csr_highest_slotid;
+ * slotid4 csr_target_highest_slotid;
+ * };
+ *
+ * union CB_SEQUENCE4res switch (nfsstat4 csr_status) {
+ * case NFS4_OK:
+ * CB_SEQUENCE4resok csr_resok4;
+ * default:
+ * void;
+ * };
+ *
+ * Our current back channel implmentation supports a single backchannel
+ * with a single slot.
+ */
+static int decode_cb_sequence4resok(struct xdr_stream *xdr,
+ struct nfsd4_callback *cb)
+{
+ struct nfsd4_session *session = cb->cb_clp->cl_cb_session;
+ int status = -ESERVERFAULT;
+ __be32 *p;
+ u32 dummy;
+
+ /*
+ * If the server returns different values for sessionID, slotID or
+ * sequence number, the server is looney tunes.
+ */
+ p = xdr_inline_decode(xdr, NFS4_MAX_SESSIONID_LEN + 4 + 4 + 4 + 4);
+ if (unlikely(p == NULL))
+ goto out_overflow;
+
+ if (memcmp(p, session->se_sessionid.data, NFS4_MAX_SESSIONID_LEN)) {
+ dprintk("NFS: %s Invalid session id\n", __func__);
+ goto out;
+ }
+ p += XDR_QUADLEN(NFS4_MAX_SESSIONID_LEN);
+
+ dummy = be32_to_cpup(p++);
+ if (dummy != session->se_cb_seq_nr) {
+ dprintk("NFS: %s Invalid sequence number\n", __func__);
+ goto out;
+ }
+
+ dummy = be32_to_cpup(p++);
+ if (dummy != 0) {
+ dprintk("NFS: %s Invalid slotid\n", __func__);
+ goto out;
+ }
+
+ /*
+ * FIXME: process highest slotid and target highest slotid
+ */
+ status = 0;
+out:
+ cb->cb_seq_status = status;
+ return status;
+out_overflow:
+ print_overflow_msg(__func__, xdr);
+ status = -EIO;
+ goto out;
+}
+
+static int decode_cb_sequence4res(struct xdr_stream *xdr,
+ struct nfsd4_callback *cb)
+{
+ int status;
+
+ if (cb->cb_clp->cl_minorversion == 0)
+ return 0;
+
+ status = decode_cb_op_status(xdr, OP_CB_SEQUENCE, &cb->cb_seq_status);
+ if (unlikely(status || cb->cb_seq_status))
+ return status;
+
+ return decode_cb_sequence4resok(xdr, cb);
+}
+
+/*
+ * NFSv4.0 and NFSv4.1 XDR encode functions
+ *
+ * NFSv4.0 callback argument types are defined in section 15 of RFC
+ * 3530: "Network File System (NFS) version 4 Protocol" and section 20
+ * of RFC 5661: "Network File System (NFS) Version 4 Minor Version 1
+ * Protocol".
+ */
+
+/*
+ * NB: Without this zero space reservation, callbacks over krb5p fail
+ */
+static void nfs4_xdr_enc_cb_null(struct rpc_rqst *req, struct xdr_stream *xdr,
+ const void *__unused)
+{
+ xdr_reserve_space(xdr, 0);
+}
+
+/*
+ * 20.2. Operation 4: CB_RECALL - Recall a Delegation
+ */
+static void nfs4_xdr_enc_cb_recall(struct rpc_rqst *req, struct xdr_stream *xdr,
+ const void *data)
+{
+ const struct nfsd4_callback *cb = data;
+ const struct nfs4_delegation *dp = cb_to_delegation(cb);
+ struct nfs4_cb_compound_hdr hdr = {
+ .ident = cb->cb_clp->cl_cb_ident,
+ .minorversion = cb->cb_clp->cl_minorversion,
+ };
+
+ encode_cb_compound4args(xdr, &hdr);
+ encode_cb_sequence4args(xdr, cb, &hdr);
+ encode_cb_recall4args(xdr, dp, &hdr);
+ encode_cb_nops(&hdr);
+}
+
+
+/*
+ * NFSv4.0 and NFSv4.1 XDR decode functions
+ *
+ * NFSv4.0 callback result types are defined in section 15 of RFC
+ * 3530: "Network File System (NFS) version 4 Protocol" and section 20
+ * of RFC 5661: "Network File System (NFS) Version 4 Minor Version 1
+ * Protocol".
+ */
+
+static int nfs4_xdr_dec_cb_null(struct rpc_rqst *req, struct xdr_stream *xdr,
+ void *__unused)
+{
+ return 0;
+}
+
+/*
+ * 20.2. Operation 4: CB_RECALL - Recall a Delegation
+ */
+static int nfs4_xdr_dec_cb_recall(struct rpc_rqst *rqstp,
+ struct xdr_stream *xdr,
+ void *data)
+{
+ struct nfsd4_callback *cb = data;
+ struct nfs4_cb_compound_hdr hdr;
+ int status;
+
+ status = decode_cb_compound4res(xdr, &hdr);
+ if (unlikely(status))
+ return status;
+
+ if (cb != NULL) {
+ status = decode_cb_sequence4res(xdr, cb);
+ if (unlikely(status || cb->cb_seq_status))
+ return status;
+ }
+
+ return decode_cb_op_status(xdr, OP_CB_RECALL, &cb->cb_status);
+}
+
+#ifdef CONFIG_NFSD_PNFS
+/*
+ * CB_LAYOUTRECALL4args
+ *
+ * struct layoutrecall_file4 {
+ * nfs_fh4 lor_fh;
+ * offset4 lor_offset;
+ * length4 lor_length;
+ * stateid4 lor_stateid;
+ * };
+ *
+ * union layoutrecall4 switch(layoutrecall_type4 lor_recalltype) {
+ * case LAYOUTRECALL4_FILE:
+ * layoutrecall_file4 lor_layout;
+ * case LAYOUTRECALL4_FSID:
+ * fsid4 lor_fsid;
+ * case LAYOUTRECALL4_ALL:
+ * void;
+ * };
+ *
+ * struct CB_LAYOUTRECALL4args {
+ * layouttype4 clora_type;
+ * layoutiomode4 clora_iomode;
+ * bool clora_changed;
+ * layoutrecall4 clora_recall;
+ * };
+ */
+static void encode_cb_layout4args(struct xdr_stream *xdr,
+ const struct nfs4_layout_stateid *ls,
+ struct nfs4_cb_compound_hdr *hdr)
+{
+ __be32 *p;
+
+ BUG_ON(hdr->minorversion == 0);
+
+ p = xdr_reserve_space(xdr, 5 * 4);
+ *p++ = cpu_to_be32(OP_CB_LAYOUTRECALL);
+ *p++ = cpu_to_be32(ls->ls_layout_type);
+ *p++ = cpu_to_be32(IOMODE_ANY);
+ *p++ = cpu_to_be32(1);
+ *p = cpu_to_be32(RETURN_FILE);
+
+ encode_nfs_fh4(xdr, &ls->ls_stid.sc_file->fi_fhandle);
+
+ p = xdr_reserve_space(xdr, 2 * 8);
+ p = xdr_encode_hyper(p, 0);
+ xdr_encode_hyper(p, NFS4_MAX_UINT64);
+
+ encode_stateid4(xdr, &ls->ls_recall_sid);
+
+ hdr->nops++;
+}
+
+static void nfs4_xdr_enc_cb_layout(struct rpc_rqst *req,
+ struct xdr_stream *xdr,
+ const void *data)
+{
+ const struct nfsd4_callback *cb = data;
+ const struct nfs4_layout_stateid *ls =
+ container_of(cb, struct nfs4_layout_stateid, ls_recall);
+ struct nfs4_cb_compound_hdr hdr = {
+ .ident = 0,
+ .minorversion = cb->cb_clp->cl_minorversion,
+ };
+
+ encode_cb_compound4args(xdr, &hdr);
+ encode_cb_sequence4args(xdr, cb, &hdr);
+ encode_cb_layout4args(xdr, ls, &hdr);
+ encode_cb_nops(&hdr);
+}
+
+static int nfs4_xdr_dec_cb_layout(struct rpc_rqst *rqstp,
+ struct xdr_stream *xdr,
+ void *data)
+{
+ struct nfsd4_callback *cb = data;
+ struct nfs4_cb_compound_hdr hdr;
+ int status;
+
+ status = decode_cb_compound4res(xdr, &hdr);
+ if (unlikely(status))
+ return status;
+
+ if (cb) {
+ status = decode_cb_sequence4res(xdr, cb);
+ if (unlikely(status || cb->cb_seq_status))
+ return status;
+ }
+ return decode_cb_op_status(xdr, OP_CB_LAYOUTRECALL, &cb->cb_status);
+}
+#endif /* CONFIG_NFSD_PNFS */
+
+static void encode_stateowner(struct xdr_stream *xdr, struct nfs4_stateowner *so)
+{
+ __be32 *p;
+
+ p = xdr_reserve_space(xdr, 8 + 4 + so->so_owner.len);
+ p = xdr_encode_opaque_fixed(p, &so->so_client->cl_clientid, 8);
+ xdr_encode_opaque(p, so->so_owner.data, so->so_owner.len);
+}
+
+static void nfs4_xdr_enc_cb_notify_lock(struct rpc_rqst *req,
+ struct xdr_stream *xdr,
+ const void *data)
+{
+ const struct nfsd4_callback *cb = data;
+ const struct nfsd4_blocked_lock *nbl =
+ container_of(cb, struct nfsd4_blocked_lock, nbl_cb);
+ struct nfs4_lockowner *lo = (struct nfs4_lockowner *)nbl->nbl_lock.fl_owner;
+ struct nfs4_cb_compound_hdr hdr = {
+ .ident = 0,
+ .minorversion = cb->cb_clp->cl_minorversion,
+ };
+
+ __be32 *p;
+
+ BUG_ON(hdr.minorversion == 0);
+
+ encode_cb_compound4args(xdr, &hdr);
+ encode_cb_sequence4args(xdr, cb, &hdr);
+
+ p = xdr_reserve_space(xdr, 4);
+ *p = cpu_to_be32(OP_CB_NOTIFY_LOCK);
+ encode_nfs_fh4(xdr, &nbl->nbl_fh);
+ encode_stateowner(xdr, &lo->lo_owner);
+ hdr.nops++;
+
+ encode_cb_nops(&hdr);
+}
+
+static int nfs4_xdr_dec_cb_notify_lock(struct rpc_rqst *rqstp,
+ struct xdr_stream *xdr,
+ void *data)
+{
+ struct nfsd4_callback *cb = data;
+ struct nfs4_cb_compound_hdr hdr;
+ int status;
+
+ status = decode_cb_compound4res(xdr, &hdr);
+ if (unlikely(status))
+ return status;
+
+ if (cb) {
+ status = decode_cb_sequence4res(xdr, cb);
+ if (unlikely(status || cb->cb_seq_status))
+ return status;
+ }
+ return decode_cb_op_status(xdr, OP_CB_NOTIFY_LOCK, &cb->cb_status);
+}
+
+/*
+ * RPC procedure tables
+ */
+#define PROC(proc, call, argtype, restype) \
+[NFSPROC4_CLNT_##proc] = { \
+ .p_proc = NFSPROC4_CB_##call, \
+ .p_encode = nfs4_xdr_enc_##argtype, \
+ .p_decode = nfs4_xdr_dec_##restype, \
+ .p_arglen = NFS4_enc_##argtype##_sz, \
+ .p_replen = NFS4_dec_##restype##_sz, \
+ .p_statidx = NFSPROC4_CB_##call, \
+ .p_name = #proc, \
+}
+
+static const struct rpc_procinfo nfs4_cb_procedures[] = {
+ PROC(CB_NULL, NULL, cb_null, cb_null),
+ PROC(CB_RECALL, COMPOUND, cb_recall, cb_recall),
+#ifdef CONFIG_NFSD_PNFS
+ PROC(CB_LAYOUT, COMPOUND, cb_layout, cb_layout),
+#endif
+ PROC(CB_NOTIFY_LOCK, COMPOUND, cb_notify_lock, cb_notify_lock),
+};
+
+static unsigned int nfs4_cb_counts[ARRAY_SIZE(nfs4_cb_procedures)];
+static const struct rpc_version nfs_cb_version4 = {
+/*
+ * Note on the callback rpc program version number: despite language in rfc
+ * 5661 section 18.36.3 requiring servers to use 4 in this field, the
+ * official xdr descriptions for both 4.0 and 4.1 specify version 1, and
+ * in practice that appears to be what implementations use. The section
+ * 18.36.3 language is expected to be fixed in an erratum.
+ */
+ .number = 1,
+ .nrprocs = ARRAY_SIZE(nfs4_cb_procedures),
+ .procs = nfs4_cb_procedures,
+ .counts = nfs4_cb_counts,
+};
+
+static const struct rpc_version *nfs_cb_version[2] = {
+ [1] = &nfs_cb_version4,
+};
+
+static const struct rpc_program cb_program;
+
+static struct rpc_stat cb_stats = {
+ .program = &cb_program
+};
+
+#define NFS4_CALLBACK 0x40000000
+static const 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(struct net *net)
+{
+ struct nfsd_net *nn = net_generic(net, nfsd_net_id);
+ return max(nn->nfsd4_lease/10, (time_t)1) * HZ;
+}
+
+static struct rpc_cred *get_backchannel_cred(struct nfs4_client *clp, struct rpc_clnt *client, struct nfsd4_session *ses)
+{
+ if (clp->cl_minorversion == 0) {
+ char *principal = clp->cl_cred.cr_targ_princ ?
+ clp->cl_cred.cr_targ_princ : "nfs";
+ struct rpc_cred *cred;
+
+ cred = rpc_lookup_machine_cred(principal);
+ if (!IS_ERR(cred))
+ get_rpccred(cred);
+ return cred;
+ } else {
+ struct rpc_auth *auth = client->cl_auth;
+ struct auth_cred acred = {};
+
+ acred.uid = ses->se_cb_sec.uid;
+ acred.gid = ses->se_cb_sec.gid;
+ return auth->au_ops->lookup_cred(client->cl_auth, &acred, 0);
+ }
+}
+
+static int setup_callback_client(struct nfs4_client *clp, struct nfs4_cb_conn *conn, struct nfsd4_session *ses)
+{
+ int maxtime = max_cb_time(clp->net);
+ struct rpc_timeout timeparms = {
+ .to_initval = maxtime,
+ .to_retries = 0,
+ .to_maxval = maxtime,
+ };
+ struct rpc_create_args args = {
+ .net = clp->net,
+ .address = (struct sockaddr *) &conn->cb_addr,
+ .addrsize = conn->cb_addrlen,
+ .saddress = (struct sockaddr *) &conn->cb_saddr,
+ .timeout = &timeparms,
+ .program = &cb_program,
+ .version = 1,
+ .flags = (RPC_CLNT_CREATE_NOPING | RPC_CLNT_CREATE_QUIET),
+ };
+ struct rpc_clnt *client;
+ struct rpc_cred *cred;
+
+ if (clp->cl_minorversion == 0) {
+ if (!clp->cl_cred.cr_principal &&
+ (clp->cl_cred.cr_flavor >= RPC_AUTH_GSS_KRB5))
+ return -EINVAL;
+ args.client_name = clp->cl_cred.cr_principal;
+ args.prognumber = conn->cb_prog;
+ args.protocol = XPRT_TRANSPORT_TCP;
+ args.authflavor = clp->cl_cred.cr_flavor;
+ clp->cl_cb_ident = conn->cb_ident;
+ } else {
+ if (!conn->cb_xprt)
+ return -EINVAL;
+ clp->cl_cb_conn.cb_xprt = conn->cb_xprt;
+ clp->cl_cb_session = ses;
+ args.bc_xprt = conn->cb_xprt;
+ args.prognumber = clp->cl_cb_session->se_cb_prog;
+ args.protocol = conn->cb_xprt->xpt_class->xcl_ident |
+ XPRT_TRANSPORT_BC;
+ args.authflavor = ses->se_cb_sec.flavor;
+ }
+ /* 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);
+ }
+ cred = get_backchannel_cred(clp, client, ses);
+ if (IS_ERR(cred)) {
+ rpc_shutdown_client(client);
+ return PTR_ERR(cred);
+ }
+ clp->cl_cb_client = client;
+ clp->cl_cb_cred = cred;
+ return 0;
+}
+
+static void warn_no_callback_path(struct nfs4_client *clp, int reason)
+{
+ dprintk("NFSD: warning: no callback path to client %.*s: error %d\n",
+ (int)clp->cl_name.len, clp->cl_name.data, reason);
+}
+
+static void nfsd4_mark_cb_down(struct nfs4_client *clp, int reason)
+{
+ if (test_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags))
+ return;
+ clp->cl_cb_state = NFSD4_CB_DOWN;
+ warn_no_callback_path(clp, reason);
+}
+
+static void nfsd4_mark_cb_fault(struct nfs4_client *clp, int reason)
+{
+ if (test_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags))
+ return;
+ clp->cl_cb_state = NFSD4_CB_FAULT;
+ warn_no_callback_path(clp, reason);
+}
+
+static void nfsd4_cb_probe_done(struct rpc_task *task, void *calldata)
+{
+ struct nfs4_client *clp = container_of(calldata, struct nfs4_client, cl_cb_null);
+
+ if (task->tk_status)
+ nfsd4_mark_cb_down(clp, task->tk_status);
+ else
+ clp->cl_cb_state = NFSD4_CB_UP;
+}
+
+static const struct rpc_call_ops nfsd4_cb_probe_ops = {
+ /* XXX: release method to ensure we set the cb channel down if
+ * necessary on early failure? */
+ .rpc_call_done = nfsd4_cb_probe_done,
+};
+
+static struct workqueue_struct *callback_wq;
+
+/*
+ * Poke the callback thread to process any updates to the callback
+ * parameters, and send a null probe.
+ */
+void nfsd4_probe_callback(struct nfs4_client *clp)
+{
+ clp->cl_cb_state = NFSD4_CB_UNKNOWN;
+ set_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags);
+ nfsd4_run_cb(&clp->cl_cb_null);
+}
+
+void nfsd4_probe_callback_sync(struct nfs4_client *clp)
+{
+ nfsd4_probe_callback(clp);
+ flush_workqueue(callback_wq);
+}
+
+void nfsd4_change_callback(struct nfs4_client *clp, struct nfs4_cb_conn *conn)
+{
+ clp->cl_cb_state = NFSD4_CB_UNKNOWN;
+ spin_lock(&clp->cl_lock);
+ memcpy(&clp->cl_cb_conn, conn, sizeof(struct nfs4_cb_conn));
+ spin_unlock(&clp->cl_lock);
+}
+
+/*
+ * There's currently a single callback channel slot.
+ * If the slot is available, then mark it busy. Otherwise, set the
+ * thread for sleeping on the callback RPC wait queue.
+ */
+static bool nfsd41_cb_get_slot(struct nfs4_client *clp, struct rpc_task *task)
+{
+ if (test_and_set_bit(0, &clp->cl_cb_slot_busy) != 0) {
+ rpc_sleep_on(&clp->cl_cb_waitq, task, NULL);
+ /* Race breaker */
+ if (test_and_set_bit(0, &clp->cl_cb_slot_busy) != 0) {
+ dprintk("%s slot is busy\n", __func__);
+ return false;
+ }
+ rpc_wake_up_queued_task(&clp->cl_cb_waitq, task);
+ }
+ return true;
+}
+
+/*
+ * TODO: cb_sequence should support referring call lists, cachethis, multiple
+ * slots, and mark callback channel down on communication errors.
+ */
+static void nfsd4_cb_prepare(struct rpc_task *task, void *calldata)
+{
+ struct nfsd4_callback *cb = calldata;
+ struct nfs4_client *clp = cb->cb_clp;
+ u32 minorversion = clp->cl_minorversion;
+
+ /*
+ * cb_seq_status is only set in decode_cb_sequence4res,
+ * and so will remain 1 if an rpc level failure occurs.
+ */
+ cb->cb_seq_status = 1;
+ cb->cb_status = 0;
+ if (minorversion) {
+ if (!nfsd41_cb_get_slot(clp, task))
+ return;
+ }
+ rpc_call_start(task);
+}
+
+static bool nfsd4_cb_sequence_done(struct rpc_task *task, struct nfsd4_callback *cb)
+{
+ struct nfs4_client *clp = cb->cb_clp;
+ struct nfsd4_session *session = clp->cl_cb_session;
+ bool ret = true;
+
+ if (!clp->cl_minorversion) {
+ /*
+ * If the backchannel connection was shut down while this
+ * task was queued, we need to resubmit it after setting up
+ * a new backchannel connection.
+ *
+ * Note that if we lost our callback connection permanently
+ * the submission code will error out, so we don't need to
+ * handle that case here.
+ */
+ if (task->tk_flags & RPC_TASK_KILLED)
+ goto need_restart;
+
+ return true;
+ }
+
+ switch (cb->cb_seq_status) {
+ case 0:
+ /*
+ * No need for lock, access serialized in nfsd4_cb_prepare
+ *
+ * RFC5661 20.9.3
+ * If CB_SEQUENCE returns an error, then the state of the slot
+ * (sequence ID, cached reply) MUST NOT change.
+ */
+ ++session->se_cb_seq_nr;
+ break;
+ case -ESERVERFAULT:
+ ++session->se_cb_seq_nr;
+ /* Fall through */
+ case 1:
+ case -NFS4ERR_BADSESSION:
+ nfsd4_mark_cb_fault(cb->cb_clp, cb->cb_seq_status);
+ ret = false;
+ break;
+ case -NFS4ERR_DELAY:
+ if (!rpc_restart_call(task))
+ goto out;
+
+ rpc_delay(task, 2 * HZ);
+ return false;
+ case -NFS4ERR_BADSLOT:
+ goto retry_nowait;
+ case -NFS4ERR_SEQ_MISORDERED:
+ if (session->se_cb_seq_nr != 1) {
+ session->se_cb_seq_nr = 1;
+ goto retry_nowait;
+ }
+ break;
+ default:
+ dprintk("%s: unprocessed error %d\n", __func__,
+ cb->cb_seq_status);
+ }
+
+ clear_bit(0, &clp->cl_cb_slot_busy);
+ rpc_wake_up_next(&clp->cl_cb_waitq);
+ dprintk("%s: freed slot, new seqid=%d\n", __func__,
+ clp->cl_cb_session->se_cb_seq_nr);
+
+ if (task->tk_flags & RPC_TASK_KILLED)
+ goto need_restart;
+out:
+ return ret;
+retry_nowait:
+ if (rpc_restart_call_prepare(task))
+ ret = false;
+ goto out;
+need_restart:
+ task->tk_status = 0;
+ cb->cb_need_restart = true;
+ return false;
+}
+
+static void nfsd4_cb_done(struct rpc_task *task, void *calldata)
+{
+ struct nfsd4_callback *cb = calldata;
+ struct nfs4_client *clp = cb->cb_clp;
+
+ dprintk("%s: minorversion=%d\n", __func__,
+ clp->cl_minorversion);
+
+ if (!nfsd4_cb_sequence_done(task, cb))
+ return;
+
+ if (cb->cb_status) {
+ WARN_ON_ONCE(task->tk_status);
+ task->tk_status = cb->cb_status;
+ }
+
+ switch (cb->cb_ops->done(cb, task)) {
+ case 0:
+ task->tk_status = 0;
+ rpc_restart_call_prepare(task);
+ return;
+ case 1:
+ break;
+ case -1:
+ /* Network partition? */
+ nfsd4_mark_cb_down(clp, task->tk_status);
+ break;
+ default:
+ BUG();
+ }
+}
+
+static void nfsd4_cb_release(void *calldata)
+{
+ struct nfsd4_callback *cb = calldata;
+
+ if (cb->cb_need_restart)
+ nfsd4_run_cb(cb);
+ else
+ cb->cb_ops->release(cb);
+
+}
+
+static const struct rpc_call_ops nfsd4_cb_ops = {
+ .rpc_call_prepare = nfsd4_cb_prepare,
+ .rpc_call_done = nfsd4_cb_done,
+ .rpc_release = nfsd4_cb_release,
+};
+
+int nfsd4_create_callback_queue(void)
+{
+ callback_wq = alloc_ordered_workqueue("nfsd4_callbacks", 0);
+ if (!callback_wq)
+ return -ENOMEM;
+ return 0;
+}
+
+void nfsd4_destroy_callback_queue(void)
+{
+ destroy_workqueue(callback_wq);
+}
+
+/* must be called under the state lock */
+void nfsd4_shutdown_callback(struct nfs4_client *clp)
+{
+ set_bit(NFSD4_CLIENT_CB_KILL, &clp->cl_flags);
+ /*
+ * Note this won't actually result in a null callback;
+ * instead, nfsd4_run_cb_null() will detect the killed
+ * client, destroy the rpc client, and stop:
+ */
+ nfsd4_run_cb(&clp->cl_cb_null);
+ flush_workqueue(callback_wq);
+}
+
+/* requires cl_lock: */
+static struct nfsd4_conn * __nfsd4_find_backchannel(struct nfs4_client *clp)
+{
+ struct nfsd4_session *s;
+ struct nfsd4_conn *c;
+
+ list_for_each_entry(s, &clp->cl_sessions, se_perclnt) {
+ list_for_each_entry(c, &s->se_conns, cn_persession) {
+ if (c->cn_flags & NFS4_CDFC4_BACK)
+ return c;
+ }
+ }
+ return NULL;
+}
+
+static void nfsd4_process_cb_update(struct nfsd4_callback *cb)
+{
+ struct nfs4_cb_conn conn;
+ struct nfs4_client *clp = cb->cb_clp;
+ struct nfsd4_session *ses = NULL;
+ struct nfsd4_conn *c;
+ int err;
+
+ /*
+ * This is either an update, or the client dying; in either case,
+ * kill the old client:
+ */
+ if (clp->cl_cb_client) {
+ rpc_shutdown_client(clp->cl_cb_client);
+ clp->cl_cb_client = NULL;
+ put_rpccred(clp->cl_cb_cred);
+ clp->cl_cb_cred = NULL;
+ }
+ if (clp->cl_cb_conn.cb_xprt) {
+ svc_xprt_put(clp->cl_cb_conn.cb_xprt);
+ clp->cl_cb_conn.cb_xprt = NULL;
+ }
+ if (test_bit(NFSD4_CLIENT_CB_KILL, &clp->cl_flags))
+ return;
+ spin_lock(&clp->cl_lock);
+ /*
+ * Only serialized callback code is allowed to clear these
+ * flags; main nfsd code can only set them:
+ */
+ BUG_ON(!(clp->cl_flags & NFSD4_CLIENT_CB_FLAG_MASK));
+ clear_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags);
+ memcpy(&conn, &cb->cb_clp->cl_cb_conn, sizeof(struct nfs4_cb_conn));
+ c = __nfsd4_find_backchannel(clp);
+ if (c) {
+ svc_xprt_get(c->cn_xprt);
+ conn.cb_xprt = c->cn_xprt;
+ ses = c->cn_session;
+ }
+ spin_unlock(&clp->cl_lock);
+
+ err = setup_callback_client(clp, &conn, ses);
+ if (err) {
+ nfsd4_mark_cb_down(clp, err);
+ return;
+ }
+}
+
+static void
+nfsd4_run_cb_work(struct work_struct *work)
+{
+ struct nfsd4_callback *cb =
+ container_of(work, struct nfsd4_callback, cb_work);
+ struct nfs4_client *clp = cb->cb_clp;
+ struct rpc_clnt *clnt;
+
+ if (cb->cb_need_restart) {
+ cb->cb_need_restart = false;
+ } else {
+ if (cb->cb_ops && cb->cb_ops->prepare)
+ cb->cb_ops->prepare(cb);
+ }
+
+ if (clp->cl_flags & NFSD4_CLIENT_CB_FLAG_MASK)
+ nfsd4_process_cb_update(cb);
+
+ clnt = clp->cl_cb_client;
+ if (!clnt) {
+ /* Callback channel broken, or client killed; give up: */
+ if (cb->cb_ops && cb->cb_ops->release)
+ cb->cb_ops->release(cb);
+ return;
+ }
+
+ /*
+ * Don't send probe messages for 4.1 or later.
+ */
+ if (!cb->cb_ops && clp->cl_minorversion) {
+ clp->cl_cb_state = NFSD4_CB_UP;
+ return;
+ }
+
+ cb->cb_msg.rpc_cred = clp->cl_cb_cred;
+ rpc_call_async(clnt, &cb->cb_msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN,
+ cb->cb_ops ? &nfsd4_cb_ops : &nfsd4_cb_probe_ops, cb);
+}
+
+void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp,
+ const struct nfsd4_callback_ops *ops, enum nfsd4_cb_op op)
+{
+ cb->cb_clp = clp;
+ cb->cb_msg.rpc_proc = &nfs4_cb_procedures[op];
+ cb->cb_msg.rpc_argp = cb;
+ cb->cb_msg.rpc_resp = cb;
+ cb->cb_ops = ops;
+ INIT_WORK(&cb->cb_work, nfsd4_run_cb_work);
+ cb->cb_seq_status = 1;
+ cb->cb_status = 0;
+ cb->cb_need_restart = false;
+}
+
+void nfsd4_run_cb(struct nfsd4_callback *cb)
+{
+ queue_work(callback_wq, &cb->cb_work);
+}