[mirror_ubuntu-artful-kernel.git] / fs / nfsd / nfs4callback.c

/*
 *  linux/fs/nfsd/nfs4callback.c
 *
 *  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/module.h>
#include <linux/list.h>
#include <linux/inet.h>
#include <linux/errno.h>
#include <linux/delay.h>
#include <linux/sched.h>
#include <linux/sunrpc/xdr.h>
#include <linux/sunrpc/svc.h>
#include <linux/sunrpc/clnt.h>
#include <linux/nfsd/nfsd.h>
#include <linux/nfsd/state.h>
#include <linux/sunrpc/sched.h>
#include <linux/nfs4.h>

#define NFSDDBG_FACILITY                NFSDDBG_PROC

#define NFSPROC4_CB_NULL 0
#define NFSPROC4_CB_COMPOUND 1

/* declarations */
static const struct rpc_call_ops nfs4_cb_null_ops;

/* 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			16
#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), __FUNCTION__); \
	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", \
			__FUNCTION__, __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_fhlen;

	RESERVE_SPACE(12+sizeof(cb_rec->cbr_stateid) + len);
	WRITE32(OP_CB_RECALL);
	WRITEMEM(&cb_rec->cbr_stateid, sizeof(stateid_t));
	WRITE32(cb_rec->cbr_trunc);
	WRITE32(len);
	WRITEMEM(cb_rec->cbr_fhval, 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,
};

/*
 * Use the SETCLIENTID credential
 */
static struct rpc_cred *
nfsd4_lookupcred(struct nfs4_client *clp, int taskflags)
{
        struct auth_cred acred;
	struct rpc_clnt *clnt = clp->cl_callback.cb_client;
	struct rpc_cred *ret;

        get_group_info(clp->cl_cred.cr_group_info);
        acred.uid = clp->cl_cred.cr_uid;
        acred.gid = clp->cl_cred.cr_gid;
        acred.group_info = clp->cl_cred.cr_group_info;

        dprintk("NFSD:     looking up %s cred\n",
                clnt->cl_auth->au_ops->au_name);
        ret = rpcauth_lookup_credcache(clnt->cl_auth, &acred, taskflags);
        put_group_info(clp->cl_cred.cr_group_info);
        return ret;
}

/*
 * Set up the callback client and put a NFSPROC4_CB_NULL on the wire...
 */
void
nfsd4_probe_callback(struct nfs4_client *clp)
{
	struct sockaddr_in	addr;
	struct nfs4_callback    *cb = &clp->cl_callback;
	struct rpc_timeout	timeparms = {
		.to_initval	= (NFSD_LEASE_TIME/4) * HZ,
		.to_retries	= 5,
		.to_maxval	= (NFSD_LEASE_TIME/2) * HZ,
		.to_exponential	= 1,
	};
	struct rpc_program *	program = &cb->cb_program;
	struct rpc_create_args args = {
		.protocol	= IPPROTO_TCP,
		.address	= (struct sockaddr *)&addr,
		.addrsize	= sizeof(addr),
		.timeout	= &timeparms,
		.program	= program,
		.version	= nfs_cb_version[1]->number,
		.authflavor	= RPC_AUTH_UNIX,	/* XXX: need AUTH_GSS... */
		.flags		= (RPC_CLNT_CREATE_NOPING),
	};
	struct rpc_message msg = {
		.rpc_proc       = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_NULL],
		.rpc_argp       = clp,
	};
	char clientname[16];
	int status;

	if (atomic_read(&cb->cb_set))
		return;

	/* 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);

	/* Initialize rpc_program */
	program->name = "nfs4_cb";
	program->number = cb->cb_prog;
	program->nrvers = ARRAY_SIZE(nfs_cb_version);
	program->version = nfs_cb_version;
	program->stats = &cb->cb_stat;

	/* Initialize rpc_stat */
	memset(program->stats, 0, sizeof(cb->cb_stat));
	program->stats->program = program;

	/* Just here to make some printk's more useful: */
	snprintf(clientname, sizeof(clientname),
		"%u.%u.%u.%u", NIPQUAD(addr.sin_addr));
	args.servername = clientname;

	/* Create RPC client */
	cb->cb_client = rpc_create(&args);
	if (IS_ERR(cb->cb_client)) {
		dprintk("NFSD: couldn't create callback client\n");
		goto out_err;
	}

	/* Kick rpciod, put the call on the wire. */
	if (rpciod_up() != 0)
		goto out_clnt;

	/* the task holds a reference to the nfs4_client struct */
	atomic_inc(&clp->cl_count);

	msg.rpc_cred = nfsd4_lookupcred(clp,0);
	if (IS_ERR(msg.rpc_cred))
		goto out_rpciod;
	status = rpc_call_async(cb->cb_client, &msg, RPC_TASK_ASYNC, &nfs4_cb_null_ops, NULL);
	put_rpccred(msg.rpc_cred);

	if (status != 0) {
		dprintk("NFSD: asynchronous NFSPROC4_CB_NULL failed!\n");
		goto out_rpciod;
	}
	return;

out_rpciod:
	atomic_dec(&clp->cl_count);
	rpciod_down();
out_clnt:
	rpc_shutdown_client(cb->cb_client);
out_err:
	cb->cb_client = NULL;
	dprintk("NFSD: warning: no callback path to client %.*s\n",
		(int)clp->cl_name.len, clp->cl_name.data);
}

static void
nfs4_cb_null(struct rpc_task *task, void *dummy)
{
	struct nfs4_client *clp = (struct nfs4_client *)task->tk_msg.rpc_argp;
	struct nfs4_callback *cb = &clp->cl_callback;
	__be32 addr = htonl(cb->cb_addr);

	dprintk("NFSD: nfs4_cb_null task->tk_status %d\n", task->tk_status);

	if (task->tk_status < 0) {
		dprintk("NFSD: callback establishment to client %.*s failed\n",
			(int)clp->cl_name.len, clp->cl_name.data);
		goto out;
	}
	atomic_set(&cb->cb_set, 1);
	dprintk("NFSD: callback set to client %u.%u.%u.%u\n", NIPQUAD(addr));
out:
	put_nfs4_client(clp);
}

static const struct rpc_call_ops nfs4_cb_null_ops = {
	.rpc_call_done = nfs4_cb_null,
};

/*
 * called with dp->dl_count inc'ed.
 * nfs4_lock_state() may or may not have been called.
 */
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;

	if ((!atomic_read(&clp->cl_callback.cb_set)) || !clnt)
		return;

	msg.rpc_cred = nfsd4_lookupcred(clp, 0);
	if (IS_ERR(msg.rpc_cred))
		goto out;

	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? */
			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:
	put_rpccred(msg.rpc_cred);
out:
	if (status == -EIO)
		atomic_set(&clp->cl_callback.cb_set, 0);
	/* Success or failure, now we're either waiting for lease expiration
	 * or deleg_return. */
	dprintk("NFSD: nfs4_cb_recall: dp %p dl_flock %p dl_count %d\n",dp, dp->dl_flock, atomic_read(&dp->dl_count));
	nfs4_put_delegation(dp);
	return;
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/fs/nfsd/nfs4callback.c
	3	*
	4	* Copyright (c) 2001 The Regents of the University of Michigan.
	5	* All rights reserved.
	6	*
	7	* Kendrick Smith <kmsmith@umich.edu>
	8	* Andy Adamson <andros@umich.edu>
	9	*
	10	* Redistribution and use in source and binary forms, with or without
	11	* modification, are permitted provided that the following conditions
	12	* are met:
	13	*
	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.
	22	*
	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.
	34	*/
	35
1da177e4 LT	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>
e8edc6e0	41	#include <linux/sched.h>
1da177e4 LT	42	#include <linux/sunrpc/xdr.h>
	43	#include <linux/sunrpc/svc.h>
	44	#include <linux/sunrpc/clnt.h>
	45	#include <linux/nfsd/nfsd.h>
	46	#include <linux/nfsd/state.h>
	47	#include <linux/sunrpc/sched.h>
	48	#include <linux/nfs4.h>
	49
	50	#define NFSDDBG_FACILITY NFSDDBG_PROC
	51
	52	#define NFSPROC4_CB_NULL 0
	53	#define NFSPROC4_CB_COMPOUND 1
	54
	55	/* declarations */
963d8fe5	56	static const struct rpc_call_ops nfs4_cb_null_ops;
1da177e4 LT	57
	58	/* Index of predefined Linux callback client operations */
	59
	60	enum {
	61	NFSPROC4_CLNT_CB_NULL = 0,
	62	NFSPROC4_CLNT_CB_RECALL,
	63	};
	64
	65	enum nfs_cb_opnum4 {
	66	OP_CB_RECALL = 4,
	67	};
	68
	69	#define NFS4_MAXTAGLEN 20
	70
	71	#define NFS4_enc_cb_null_sz 0
	72	#define NFS4_dec_cb_null_sz 0
	73	#define cb_compound_enc_hdr_sz 4
	74	#define cb_compound_dec_hdr_sz (3 + (NFS4_MAXTAGLEN >> 2))
	75	#define op_enc_sz 1
	76	#define op_dec_sz 2
	77	#define enc_nfs4_fh_sz (1 + (NFS4_FHSIZE >> 2))
	78	#define enc_stateid_sz 16
	79	#define NFS4_enc_cb_recall_sz (cb_compound_enc_hdr_sz + \
	80	1 + enc_stateid_sz + \
	81	enc_nfs4_fh_sz)
	82
	83	#define NFS4_dec_cb_recall_sz (cb_compound_dec_hdr_sz + \
	84	op_dec_sz)
	85
	86	/*
	87	* Generic encode routines from fs/nfs/nfs4xdr.c
	88	*/
f00f328f AV	89	static inline __be32 *
f00f328f AV	90	xdr_writemem(__be32 p, const void ptr, int nbytes)
1da177e4 LT	91	{
	92	int tmp = XDR_QUADLEN(nbytes);
	93	if (!tmp)
	94	return p;
	95	p[tmp-1] = 0;
	96	memcpy(p, ptr, nbytes);
	97	return p + tmp;
	98	}
	99
	100	#define WRITE32(n) *p++ = htonl(n)
	101	#define WRITEMEM(ptr,nbytes) do { \
	102	p = xdr_writemem(p, ptr, nbytes); \
	103	} while (0)
	104	#define RESERVE_SPACE(nbytes) do { \
	105	p = xdr_reserve_space(xdr, nbytes); \
	106	if (!p) dprintk("NFSD: RESERVE_SPACE(%d) failed in function %s\n", (int) (nbytes), __FUNCTION__); \
	107	BUG_ON(!p); \
	108	} while (0)
	109
	110	/*
	111	* Generic decode routines from fs/nfs/nfs4xdr.c
	112	*/
	113	#define DECODE_TAIL \
	114	status = 0; \
	115	out: \
	116	return status; \
	117	xdr_error: \
	118	dprintk("NFSD: xdr error! (%s:%d)\n", __FILE__, __LINE__); \
	119	status = -EIO; \
	120	goto out
	121
	122	#define READ32(x) (x) = ntohl(*p++)
	123	#define READ64(x) do { \
	124	(x) = (u64)ntohl(*p++) << 32; \
	125	(x) \|= ntohl(*p++); \
	126	} while (0)
	127	#define READTIME(x) do { \
	128	p++; \
	129	(x.tv_sec) = ntohl(*p++); \
	130	(x.tv_nsec) = ntohl(*p++); \
	131	} while (0)
	132	#define READ_BUF(nbytes) do { \
	133	p = xdr_inline_decode(xdr, nbytes); \
	134	if (!p) { \
3e3b4800	135	dprintk("NFSD: %s: reply buffer overflowed in line %d.\n", \
1da177e4 LT	136	__FUNCTION__, __LINE__); \
	137	return -EIO; \
	138	} \
	139	} while (0)
	140
	141	struct nfs4_cb_compound_hdr {
	142	int status;
	143	u32 ident;
	144	u32 nops;
	145	u32 taglen;
	146	char * tag;
	147	};
	148
	149	static struct {
	150	int stat;
	151	int errno;
	152	} nfs_cb_errtbl[] = {
	153	{ NFS4_OK, 0 },
	154	{ NFS4ERR_PERM, EPERM },
	155	{ NFS4ERR_NOENT, ENOENT },
	156	{ NFS4ERR_IO, EIO },
	157	{ NFS4ERR_NXIO, ENXIO },
	158	{ NFS4ERR_ACCESS, EACCES },
	159	{ NFS4ERR_EXIST, EEXIST },
	160	{ NFS4ERR_XDEV, EXDEV },
	161	{ NFS4ERR_NOTDIR, ENOTDIR },
	162	{ NFS4ERR_ISDIR, EISDIR },
	163	{ NFS4ERR_INVAL, EINVAL },
	164	{ NFS4ERR_FBIG, EFBIG },
	165	{ NFS4ERR_NOSPC, ENOSPC },
	166	{ NFS4ERR_ROFS, EROFS },
	167	{ NFS4ERR_MLINK, EMLINK },
	168	{ NFS4ERR_NAMETOOLONG, ENAMETOOLONG },
	169	{ NFS4ERR_NOTEMPTY, ENOTEMPTY },
	170	{ NFS4ERR_DQUOT, EDQUOT },
	171	{ NFS4ERR_STALE, ESTALE },
	172	{ NFS4ERR_BADHANDLE, EBADHANDLE },
	173	{ NFS4ERR_BAD_COOKIE, EBADCOOKIE },
	174	{ NFS4ERR_NOTSUPP, ENOTSUPP },
	175	{ NFS4ERR_TOOSMALL, ETOOSMALL },
	176	{ NFS4ERR_SERVERFAULT, ESERVERFAULT },
	177	{ NFS4ERR_BADTYPE, EBADTYPE },
	178	{ NFS4ERR_LOCKED, EAGAIN },
	179	{ NFS4ERR_RESOURCE, EREMOTEIO },
	180	{ NFS4ERR_SYMLINK, ELOOP },
	181	{ NFS4ERR_OP_ILLEGAL, EOPNOTSUPP },
	182	{ NFS4ERR_DEADLOCK, EDEADLK },
	183	{ -1, EIO }
	184	};
	185
	186	static int
	187	nfs_cb_stat_to_errno(int stat)
	188	{
	189	int i;
	190	for (i = 0; nfs_cb_errtbl[i].stat != -1; i++) {
	191	if (nfs_cb_errtbl[i].stat == stat)
	192	return nfs_cb_errtbl[i].errno;
	193	}
	194	/* If we cannot translate the error, the recovery routines should
	195	* handle it.
	196	* Note: remaining NFSv4 error codes have values > 10000, so should
	197	* not conflict with native Linux error codes.
	198	*/
	199	return stat;
200	}
201
202	/*
203	* XDR encode
204	*/
205
206	static int
207	encode_cb_compound_hdr(struct xdr_stream xdr, struct nfs4_cb_compound_hdr hdr)
208	{
f00f328f	209	__be32 * p;
1da177e4 LT	210
	211	RESERVE_SPACE(16);
	212	WRITE32(0); /* tag length is always 0 */
	213	WRITE32(NFS4_MINOR_VERSION);
	214	WRITE32(hdr->ident);
	215	WRITE32(hdr->nops);
	216	return 0;
	217	}
	218
	219	static int
	220	encode_cb_recall(struct xdr_stream xdr, struct nfs4_cb_recall cb_rec)
	221	{
f00f328f	222	__be32 *p;
1da177e4 LT	223	int len = cb_rec->cbr_fhlen;
	224
	225	RESERVE_SPACE(12+sizeof(cb_rec->cbr_stateid) + len);
	226	WRITE32(OP_CB_RECALL);
	227	WRITEMEM(&cb_rec->cbr_stateid, sizeof(stateid_t));
	228	WRITE32(cb_rec->cbr_trunc);
	229	WRITE32(len);
	230	WRITEMEM(cb_rec->cbr_fhval, len);
	231	return 0;
	232	}
	233
	234	static int
f00f328f	235	nfs4_xdr_enc_cb_null(struct rpc_rqst req, __be32 p)
1da177e4 LT	236	{
	237	struct xdr_stream xdrs, *xdr = &xdrs;
	238
	239	xdr_init_encode(&xdrs, &req->rq_snd_buf, p);
	240	RESERVE_SPACE(0);
	241	return 0;
	242	}
	243
	244	static int
f00f328f	245	nfs4_xdr_enc_cb_recall(struct rpc_rqst req, __be32 p, struct nfs4_cb_recall *args)
1da177e4 LT	246	{
	247	struct xdr_stream xdr;
	248	struct nfs4_cb_compound_hdr hdr = {
	249	.ident = args->cbr_ident,
	250	.nops = 1,
	251	};
	252
	253	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
	254	encode_cb_compound_hdr(&xdr, &hdr);
	255	return (encode_cb_recall(&xdr, args));
	256	}
	257
	258
	259	static int
	260	decode_cb_compound_hdr(struct xdr_stream xdr, struct nfs4_cb_compound_hdr hdr){
f00f328f	261	__be32 *p;
1da177e4 LT	262
	263	READ_BUF(8);
	264	READ32(hdr->status);
	265	READ32(hdr->taglen);
	266	READ_BUF(hdr->taglen + 4);
	267	hdr->tag = (char *)p;
	268	p += XDR_QUADLEN(hdr->taglen);
	269	READ32(hdr->nops);
	270	return 0;
	271	}
	272
	273	static int
	274	decode_cb_op_hdr(struct xdr_stream *xdr, enum nfs_opnum4 expected)
	275	{
f00f328f	276	__be32 *p;
1da177e4 LT	277	u32 op;
	278	int32_t nfserr;
	279
	280	READ_BUF(8);
	281	READ32(op);
	282	if (op != expected) {
	283	dprintk("NFSD: decode_cb_op_hdr: Callback server returned "
	284	" operation %d but we issued a request for %d\n",
	285	op, expected);
	286	return -EIO;
	287	}
	288	READ32(nfserr);
	289	if (nfserr != NFS_OK)
	290	return -nfs_cb_stat_to_errno(nfserr);
	291	return 0;
	292	}
	293
	294	static int
f00f328f	295	nfs4_xdr_dec_cb_null(struct rpc_rqst req, __be32 p)
1da177e4 LT	296	{
	297	return 0;
	298	}
	299
	300	static int
f00f328f	301	nfs4_xdr_dec_cb_recall(struct rpc_rqst rqstp, __be32 p)
1da177e4 LT	302	{
	303	struct xdr_stream xdr;
	304	struct nfs4_cb_compound_hdr hdr;
	305	int status;
	306
	307	xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p);
	308	status = decode_cb_compound_hdr(&xdr, &hdr);
	309	if (status)
	310	goto out;
	311	status = decode_cb_op_hdr(&xdr, OP_CB_RECALL);
	312	out:
	313	return status;
	314	}
	315
	316	/*
	317	* RPC procedure tables
	318	*/
1da177e4 LT	319	#define PROC(proc, call, argtype, restype) \
	320	[NFSPROC4_CLNT_##proc] = { \
	321	.p_proc = NFSPROC4_CB_##call, \
	322	.p_encode = (kxdrproc_t) nfs4_xdr_##argtype, \
	323	.p_decode = (kxdrproc_t) nfs4_xdr_##restype, \
2bea90d4 CL	324	.p_arglen = NFS4_##argtype##_sz, \
2bea90d4 CL	325	.p_replen = NFS4_##restype##_sz, \
cc0175c1 CL	326	.p_statidx = NFSPROC4_CB_##call, \
cc0175c1 CL	327	.p_name = #proc, \
1da177e4 LT	328	}
1da177e4 LT	329
fd39ca9a	330	static struct rpc_procinfo nfs4_cb_procedures[] = {
1da177e4 LT	331	PROC(CB_NULL, NULL, enc_cb_null, dec_cb_null),
	332	PROC(CB_RECALL, COMPOUND, enc_cb_recall, dec_cb_recall),
	333	};
	334
fd39ca9a	335	static struct rpc_version nfs_cb_version4 = {
1da177e4	336	.number = 1,
e8c96f8c	337	.nrprocs = ARRAY_SIZE(nfs4_cb_procedures),
1da177e4 LT	338	.procs = nfs4_cb_procedures
	339	};
	340
	341	static struct rpc_version * nfs_cb_version[] = {
	342	NULL,
	343	&nfs_cb_version4,
	344	};
	345
	346	/*
	347	* Use the SETCLIENTID credential
	348	*/
fd39ca9a	349	static struct rpc_cred *
1da177e4 LT	350	nfsd4_lookupcred(struct nfs4_client *clp, int taskflags)
	351	{
	352	struct auth_cred acred;
	353	struct rpc_clnt *clnt = clp->cl_callback.cb_client;
	354	struct rpc_cred *ret;
	355
	356	get_group_info(clp->cl_cred.cr_group_info);
	357	acred.uid = clp->cl_cred.cr_uid;
	358	acred.gid = clp->cl_cred.cr_gid;
	359	acred.group_info = clp->cl_cred.cr_group_info;
	360
	361	dprintk("NFSD: looking up %s cred\n",
	362	clnt->cl_auth->au_ops->au_name);
	363	ret = rpcauth_lookup_credcache(clnt->cl_auth, &acred, taskflags);
	364	put_group_info(clp->cl_cred.cr_group_info);
	365	return ret;
	366	}
	367
	368	/*
	369	* Set up the callback client and put a NFSPROC4_CB_NULL on the wire...
	370	*/
	371	void
	372	nfsd4_probe_callback(struct nfs4_client *clp)
	373	{
	374	struct sockaddr_in addr;
	375	struct nfs4_callback *cb = &clp->cl_callback;
ae5c7947 CL	376	struct rpc_timeout timeparms = {
	377	.to_initval = (NFSD_LEASE_TIME/4) * HZ,
	378	.to_retries = 5,
	379	.to_maxval = (NFSD_LEASE_TIME/2) * HZ,
	380	.to_exponential = 1,
	381	};
1da177e4	382	struct rpc_program * program = &cb->cb_program;
ae5c7947 CL	383	struct rpc_create_args args = {
	384	.protocol = IPPROTO_TCP,
	385	.address = (struct sockaddr *)&addr,
	386	.addrsize = sizeof(addr),
	387	.timeout = &timeparms,
ae5c7947 CL	388	.program = program,
	389	.version = nfs_cb_version[1]->number,
	390	.authflavor = RPC_AUTH_UNIX, /* XXX: need AUTH_GSS... */
	391	.flags = (RPC_CLNT_CREATE_NOPING),
	392	};
1da177e4 LT	393	struct rpc_message msg = {
	394	.rpc_proc = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_NULL],
	395	.rpc_argp = clp,
	396	};
f534a257	397	char clientname[16];
1da177e4 LT	398	int status;
1da177e4 LT	399
cb36d634	400	if (atomic_read(&cb->cb_set))
1da177e4 LT	401	return;
	402
	403	/* Initialize address */
	404	memset(&addr, 0, sizeof(addr));
	405	addr.sin_family = AF_INET;
	406	addr.sin_port = htons(cb->cb_port);
	407	addr.sin_addr.s_addr = htonl(cb->cb_addr);
	408
1da177e4 LT	409	/* Initialize rpc_program */
	410	program->name = "nfs4_cb";
	411	program->number = cb->cb_prog;
e8c96f8c	412	program->nrvers = ARRAY_SIZE(nfs_cb_version);
1da177e4	413	program->version = nfs_cb_version;
ae5c7947	414	program->stats = &cb->cb_stat;
1da177e4 LT	415
1da177e4 LT	416	/* Initialize rpc_stat */
ae5c7947 CL	417	memset(program->stats, 0, sizeof(cb->cb_stat));
	418	program->stats->program = program;
	419
f534a257 BF	420	/* Just here to make some printk's more useful: */
	421	snprintf(clientname, sizeof(clientname),
	422	"%u.%u.%u.%u", NIPQUAD(addr.sin_addr));
	423	args.servername = clientname;
	424
ae5c7947 CL	425	/* Create RPC client */
ae5c7947 CL	426	cb->cb_client = rpc_create(&args);
0942176f	427	if (IS_ERR(cb->cb_client)) {
1da177e4	428	dprintk("NFSD: couldn't create callback client\n");
5b616f5d	429	goto out_err;
1da177e4	430	}
1da177e4 LT	431
1da177e4 LT	432	/* Kick rpciod, put the call on the wire. */
ae5c7947	433	if (rpciod_up() != 0)
1da177e4	434	goto out_clnt;
541e0e09 N	435
541e0e09 N	436	/* the task holds a reference to the nfs4_client struct */
1da177e4 LT	437	atomic_inc(&clp->cl_count);
	438
	439	msg.rpc_cred = nfsd4_lookupcred(clp,0);
	440	if (IS_ERR(msg.rpc_cred))
	441	goto out_rpciod;
ae5c7947	442	status = rpc_call_async(cb->cb_client, &msg, RPC_TASK_ASYNC, &nfs4_cb_null_ops, NULL);
1da177e4 LT	443	put_rpccred(msg.rpc_cred);
	444
	445	if (status != 0) {
	446	dprintk("NFSD: asynchronous NFSPROC4_CB_NULL failed!\n");
	447	goto out_rpciod;
	448	}
	449	return;
	450
	451	out_rpciod:
	452	atomic_dec(&clp->cl_count);
	453	rpciod_down();
	454	out_clnt:
ae5c7947	455	rpc_shutdown_client(cb->cb_client);
1da177e4	456	out_err:
0942176f	457	cb->cb_client = NULL;
1da177e4 LT	458	dprintk("NFSD: warning: no callback path to client %.*s\n",
1da177e4 LT	459	(int)clp->cl_name.len, clp->cl_name.data);
1da177e4 LT	460	}
	461
	462	static void
963d8fe5	463	nfs4_cb_null(struct rpc_task task, void dummy)
1da177e4 LT	464	{
	465	struct nfs4_client clp = (struct nfs4_client )task->tk_msg.rpc_argp;
	466	struct nfs4_callback *cb = &clp->cl_callback;
c7afef1f	467	__be32 addr = htonl(cb->cb_addr);
1da177e4 LT	468
	469	dprintk("NFSD: nfs4_cb_null task->tk_status %d\n", task->tk_status);
	470
	471	if (task->tk_status < 0) {
	472	dprintk("NFSD: callback establishment to client %.*s failed\n",
	473	(int)clp->cl_name.len, clp->cl_name.data);
	474	goto out;
	475	}
	476	atomic_set(&cb->cb_set, 1);
	477	dprintk("NFSD: callback set to client %u.%u.%u.%u\n", NIPQUAD(addr));
	478	out:
	479	put_nfs4_client(clp);
	480	}
	481
963d8fe5 TM	482	static const struct rpc_call_ops nfs4_cb_null_ops = {
	483	.rpc_call_done = nfs4_cb_null,
	484	};
	485
1da177e4 LT	486	/*
	487	* called with dp->dl_count inc'ed.
	488	* nfs4_lock_state() may or may not have been called.
	489	*/
	490	void
	491	nfsd4_cb_recall(struct nfs4_delegation *dp)
	492	{
	493	struct nfs4_client *clp = dp->dl_client;
	494	struct rpc_clnt *clnt = clp->cl_callback.cb_client;
	495	struct nfs4_cb_recall *cbr = &dp->dl_recall;
	496	struct rpc_message msg = {
	497	.rpc_proc = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_RECALL],
	498	.rpc_argp = cbr,
	499	};
	500	int retries = 1;
	501	int status = 0;
	502
	503	if ((!atomic_read(&clp->cl_callback.cb_set)) \|\| !clnt)
	504	return;
	505
	506	msg.rpc_cred = nfsd4_lookupcred(clp, 0);
	507	if (IS_ERR(msg.rpc_cred))
	508	goto out;
	509
	510	cbr->cbr_trunc = 0; /* XXX need to implement truncate optimization */
	511	cbr->cbr_dp = dp;
	512
	513	status = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT);
	514	while (retries--) {
	515	switch (status) {
	516	case -EIO:
	517	/* Network partition? */
	518	case -EBADHANDLE:
	519	case -NFS4ERR_BAD_STATEID:
	520	/* Race: client probably got cb_recall
	521	* before open reply granting delegation */
	522	break;
	523	default:
	524	goto out_put_cred;
	525	}
	526	ssleep(2);
	527	status = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT);
	528	}
	529	out_put_cred:
	530	put_rpccred(msg.rpc_cred);
	531	out:
	532	if (status == -EIO)
	533	atomic_set(&clp->cl_callback.cb_set, 0);
	534	/* Success or failure, now we're either waiting for lease expiration
	535	* or deleg_return. */
	536	dprintk("NFSD: nfs4_cb_recall: dp %p dl_flock %p dl_count %d\n",dp, dp->dl_flock, atomic_read(&dp->dl_count));
	537	nfs4_put_delegation(dp);
	538	return;
	539	}