[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/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 u32 *
xdr_writemem(u32 *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.", \
			__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)
{
	u32 * 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)
{
	u32 *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, u32 *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, u32 *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){
        u32 *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)
{
	u32 *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, u32 *p)
{
	return 0;
}

static int
nfs4_xdr_dec_cb_recall(struct rpc_rqst *rqstp, u32 *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
 */
#ifndef MAX
# define MAX(a, b)      (((a) > (b))? (a) : (b))
#endif

#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_bufsiz = MAX(NFS4_##argtype##_sz,NFS4_##restype##_sz) << 2,  \
        .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;
	struct rpc_xprt *	xprt;
	struct rpc_program *	program = &cb->cb_program;
	struct rpc_stat *	stat = &cb->cb_stat;
	struct rpc_clnt *	clnt;
	struct rpc_message msg = {
		.rpc_proc       = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_NULL],
		.rpc_argp       = clp,
	};
	char                    hostname[32];
	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 timeout */
	timeparms.to_initval = (NFSD_LEASE_TIME/4) * HZ;
	timeparms.to_retries = 0;
	timeparms.to_maxval = (NFSD_LEASE_TIME/2) * HZ;
	timeparms.to_exponential = 1;

	/* Create RPC transport */
	xprt = xprt_create_proto(IPPROTO_TCP, &addr, &timeparms);
	if (IS_ERR(xprt)) {
		dprintk("NFSD: couldn't create callback transport!\n");
		goto out_err;
	}

	/* 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 = stat;

	/* Initialize rpc_stat */
	memset(stat, 0, sizeof(struct rpc_stat));
	stat->program = program;

	/* Create RPC client
 	 *
	 * XXX AUTH_UNIX only - need AUTH_GSS....
	 */
	sprintf(hostname, "%u.%u.%u.%u", NIPQUAD(addr.sin_addr.s_addr));
	clnt = rpc_new_client(xprt, hostname, program, 1, RPC_AUTH_UNIX);
	if (IS_ERR(clnt)) {
		dprintk("NFSD: couldn't create callback client\n");
		goto out_err;
	}
	clnt->cl_intr = 0;
	clnt->cl_softrtry = 1;

	/* Kick rpciod, put the call on the wire. */

	if (rpciod_up() != 0) {
		dprintk("nfsd: couldn't start rpciod for callbacks!\n");
		goto out_clnt;
	}

	cb->cb_client = 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(clnt, &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();
	cb->cb_client = NULL;
out_clnt:
	rpc_shutdown_client(clnt);
out_err:
	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;
	u32 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>
	41	#include <linux/sunrpc/xdr.h>
	42	#include <linux/sunrpc/svc.h>
	43	#include <linux/sunrpc/clnt.h>
	44	#include <linux/nfsd/nfsd.h>
	45	#include <linux/nfsd/state.h>
	46	#include <linux/sunrpc/sched.h>
	47	#include <linux/nfs4.h>
	48
	49	#define NFSDDBG_FACILITY NFSDDBG_PROC
	50
	51	#define NFSPROC4_CB_NULL 0
	52	#define NFSPROC4_CB_COMPOUND 1
	53
	54	/* declarations */
963d8fe5	55	static const struct rpc_call_ops nfs4_cb_null_ops;
1da177e4 LT	56
	57	/* Index of predefined Linux callback client operations */
	58
	59	enum {
	60	NFSPROC4_CLNT_CB_NULL = 0,
	61	NFSPROC4_CLNT_CB_RECALL,
	62	};
	63
	64	enum nfs_cb_opnum4 {
	65	OP_CB_RECALL = 4,
	66	};
	67
	68	#define NFS4_MAXTAGLEN 20
	69
	70	#define NFS4_enc_cb_null_sz 0
	71	#define NFS4_dec_cb_null_sz 0
	72	#define cb_compound_enc_hdr_sz 4
	73	#define cb_compound_dec_hdr_sz (3 + (NFS4_MAXTAGLEN >> 2))
	74	#define op_enc_sz 1
	75	#define op_dec_sz 2
	76	#define enc_nfs4_fh_sz (1 + (NFS4_FHSIZE >> 2))
	77	#define enc_stateid_sz 16
	78	#define NFS4_enc_cb_recall_sz (cb_compound_enc_hdr_sz + \
	79	1 + enc_stateid_sz + \
	80	enc_nfs4_fh_sz)
	81
	82	#define NFS4_dec_cb_recall_sz (cb_compound_dec_hdr_sz + \
	83	op_dec_sz)
	84
	85	/*
	86	* Generic encode routines from fs/nfs/nfs4xdr.c
	87	*/
	88	static inline u32 *
	89	xdr_writemem(u32 p, const void ptr, int nbytes)
	90	{
	91	int tmp = XDR_QUADLEN(nbytes);
	92	if (!tmp)
	93	return p;
	94	p[tmp-1] = 0;
	95	memcpy(p, ptr, nbytes);
	96	return p + tmp;
	97	}
	98
	99	#define WRITE32(n) *p++ = htonl(n)
	100	#define WRITEMEM(ptr,nbytes) do { \
	101	p = xdr_writemem(p, ptr, nbytes); \
	102	} while (0)
	103	#define RESERVE_SPACE(nbytes) do { \
	104	p = xdr_reserve_space(xdr, nbytes); \
	105	if (!p) dprintk("NFSD: RESERVE_SPACE(%d) failed in function %s\n", (int) (nbytes), __FUNCTION__); \
	106	BUG_ON(!p); \
	107	} while (0)
	108
	109	/*
	110	* Generic decode routines from fs/nfs/nfs4xdr.c
	111	*/
	112	#define DECODE_TAIL \
	113	status = 0; \
	114	out: \
	115	return status; \
	116	xdr_error: \
	117	dprintk("NFSD: xdr error! (%s:%d)\n", __FILE__, __LINE__); \
	118	status = -EIO; \
	119	goto out
120
121	#define READ32(x) (x) = ntohl(*p++)
122	#define READ64(x) do { \
123	(x) = (u64)ntohl(*p++) << 32; \
124	(x) \|= ntohl(*p++); \
125	} while (0)
126	#define READTIME(x) do { \
127	p++; \
128	(x.tv_sec) = ntohl(*p++); \
129	(x.tv_nsec) = ntohl(*p++); \
130	} while (0)
131	#define READ_BUF(nbytes) do { \
132	p = xdr_inline_decode(xdr, nbytes); \
133	if (!p) { \
134	dprintk("NFSD: %s: reply buffer overflowed in line %d.", \
135	__FUNCTION__, __LINE__); \
136	return -EIO; \
137	} \
138	} while (0)
139
140	struct nfs4_cb_compound_hdr {
141	int status;
142	u32 ident;
143	u32 nops;
144	u32 taglen;
145	char * tag;
146	};
147
148	static struct {
149	int stat;
150	int errno;
151	} nfs_cb_errtbl[] = {
152	{ NFS4_OK, 0 },
153	{ NFS4ERR_PERM, EPERM },
154	{ NFS4ERR_NOENT, ENOENT },
155	{ NFS4ERR_IO, EIO },
156	{ NFS4ERR_NXIO, ENXIO },
157	{ NFS4ERR_ACCESS, EACCES },
158	{ NFS4ERR_EXIST, EEXIST },
159	{ NFS4ERR_XDEV, EXDEV },
160	{ NFS4ERR_NOTDIR, ENOTDIR },
161	{ NFS4ERR_ISDIR, EISDIR },
162	{ NFS4ERR_INVAL, EINVAL },
163	{ NFS4ERR_FBIG, EFBIG },
164	{ NFS4ERR_NOSPC, ENOSPC },
165	{ NFS4ERR_ROFS, EROFS },
166	{ NFS4ERR_MLINK, EMLINK },
167	{ NFS4ERR_NAMETOOLONG, ENAMETOOLONG },
168	{ NFS4ERR_NOTEMPTY, ENOTEMPTY },
169	{ NFS4ERR_DQUOT, EDQUOT },
170	{ NFS4ERR_STALE, ESTALE },
171	{ NFS4ERR_BADHANDLE, EBADHANDLE },
172	{ NFS4ERR_BAD_COOKIE, EBADCOOKIE },
173	{ NFS4ERR_NOTSUPP, ENOTSUPP },
174	{ NFS4ERR_TOOSMALL, ETOOSMALL },
175	{ NFS4ERR_SERVERFAULT, ESERVERFAULT },
176	{ NFS4ERR_BADTYPE, EBADTYPE },
177	{ NFS4ERR_LOCKED, EAGAIN },
178	{ NFS4ERR_RESOURCE, EREMOTEIO },
179	{ NFS4ERR_SYMLINK, ELOOP },
180	{ NFS4ERR_OP_ILLEGAL, EOPNOTSUPP },
181	{ NFS4ERR_DEADLOCK, EDEADLK },
182	{ -1, EIO }
183	};
184
185	static int
186	nfs_cb_stat_to_errno(int stat)
187	{
188	int i;
189	for (i = 0; nfs_cb_errtbl[i].stat != -1; i++) {
190	if (nfs_cb_errtbl[i].stat == stat)
191	return nfs_cb_errtbl[i].errno;
192	}
193	/* If we cannot translate the error, the recovery routines should
194	* handle it.
195	* Note: remaining NFSv4 error codes have values > 10000, so should
196	* not conflict with native Linux error codes.
197	*/
198	return stat;
199	}
200
201	/*
202	* XDR encode
203	*/
204
205	static int
206	encode_cb_compound_hdr(struct xdr_stream xdr, struct nfs4_cb_compound_hdr hdr)
207	{
208	u32 * p;
209
210	RESERVE_SPACE(16);
211	WRITE32(0); /* tag length is always 0 */
212	WRITE32(NFS4_MINOR_VERSION);
213	WRITE32(hdr->ident);
214	WRITE32(hdr->nops);
215	return 0;
216	}
217
218	static int
219	encode_cb_recall(struct xdr_stream xdr, struct nfs4_cb_recall cb_rec)
220	{
221	u32 *p;
222	int len = cb_rec->cbr_fhlen;
223
224	RESERVE_SPACE(12+sizeof(cb_rec->cbr_stateid) + len);
225	WRITE32(OP_CB_RECALL);
226	WRITEMEM(&cb_rec->cbr_stateid, sizeof(stateid_t));
227	WRITE32(cb_rec->cbr_trunc);
228	WRITE32(len);
229	WRITEMEM(cb_rec->cbr_fhval, len);
230	return 0;
231	}
232
233	static int
234	nfs4_xdr_enc_cb_null(struct rpc_rqst req, u32 p)
235	{
236	struct xdr_stream xdrs, *xdr = &xdrs;
237
238	xdr_init_encode(&xdrs, &req->rq_snd_buf, p);
239	RESERVE_SPACE(0);
240	return 0;
241	}
242
243	static int
244	nfs4_xdr_enc_cb_recall(struct rpc_rqst req, u32 p, struct nfs4_cb_recall *args)
245	{
246	struct xdr_stream xdr;
247	struct nfs4_cb_compound_hdr hdr = {
248	.ident = args->cbr_ident,
249	.nops = 1,
250	};
251
252	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
253	encode_cb_compound_hdr(&xdr, &hdr);
254	return (encode_cb_recall(&xdr, args));
255	}
256
257
258	static int
259	decode_cb_compound_hdr(struct xdr_stream xdr, struct nfs4_cb_compound_hdr hdr){
260	u32 *p;
261
262	READ_BUF(8);
263	READ32(hdr->status);
264	READ32(hdr->taglen);
265	READ_BUF(hdr->taglen + 4);
266	hdr->tag = (char *)p;
267	p += XDR_QUADLEN(hdr->taglen);
268	READ32(hdr->nops);
269	return 0;
270	}
271
272	static int
273	decode_cb_op_hdr(struct xdr_stream *xdr, enum nfs_opnum4 expected)
274	{
275	u32 *p;
276	u32 op;
277	int32_t nfserr;
278
279	READ_BUF(8);
280	READ32(op);
281	if (op != expected) {
282	dprintk("NFSD: decode_cb_op_hdr: Callback server returned "
283	" operation %d but we issued a request for %d\n",
284	op, expected);
285	return -EIO;
286	}
287	READ32(nfserr);
288	if (nfserr != NFS_OK)
289	return -nfs_cb_stat_to_errno(nfserr);
290	return 0;
291	}
292
293	static int
294	nfs4_xdr_dec_cb_null(struct rpc_rqst req, u32 p)
295	{
296	return 0;
297	}
298
299	static int
300	nfs4_xdr_dec_cb_recall(struct rpc_rqst rqstp, u32 p)
301	{
302	struct xdr_stream xdr;
303	struct nfs4_cb_compound_hdr hdr;
304	int status;
305
306	xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p);
307	status = decode_cb_compound_hdr(&xdr, &hdr);
308	if (status)
309	goto out;
310	status = decode_cb_op_hdr(&xdr, OP_CB_RECALL);
311	out:
312	return status;
313	}
314
315	/*
316	* RPC procedure tables
317	*/
318	#ifndef MAX
319	# define MAX(a, b) (((a) > (b))? (a) : (b))
320	#endif
321
322	#define PROC(proc, call, argtype, restype) \
323	[NFSPROC4_CLNT_##proc] = { \
324	.p_proc = NFSPROC4_CB_##call, \
325	.p_encode = (kxdrproc_t) nfs4_xdr_##argtype, \
326	.p_decode = (kxdrproc_t) nfs4_xdr_##restype, \
327	.p_bufsiz = MAX(NFS4_##argtype##_sz,NFS4_##restype##_sz) << 2, \
cc0175c1 CL	328	.p_statidx = NFSPROC4_CB_##call, \
cc0175c1 CL	329	.p_name = #proc, \
1da177e4 LT	330	}
1da177e4 LT	331
fd39ca9a	332	static struct rpc_procinfo nfs4_cb_procedures[] = {
1da177e4 LT	333	PROC(CB_NULL, NULL, enc_cb_null, dec_cb_null),
	334	PROC(CB_RECALL, COMPOUND, enc_cb_recall, dec_cb_recall),
	335	};
	336
fd39ca9a	337	static struct rpc_version nfs_cb_version4 = {
1da177e4	338	.number = 1,
e8c96f8c	339	.nrprocs = ARRAY_SIZE(nfs4_cb_procedures),
1da177e4 LT	340	.procs = nfs4_cb_procedures
	341	};
	342
	343	static struct rpc_version * nfs_cb_version[] = {
	344	NULL,
	345	&nfs_cb_version4,
	346	};
	347
	348	/*
	349	* Use the SETCLIENTID credential
	350	*/
fd39ca9a	351	static struct rpc_cred *
1da177e4 LT	352	nfsd4_lookupcred(struct nfs4_client *clp, int taskflags)
	353	{
	354	struct auth_cred acred;
	355	struct rpc_clnt *clnt = clp->cl_callback.cb_client;
	356	struct rpc_cred *ret;
	357
	358	get_group_info(clp->cl_cred.cr_group_info);
	359	acred.uid = clp->cl_cred.cr_uid;
	360	acred.gid = clp->cl_cred.cr_gid;
	361	acred.group_info = clp->cl_cred.cr_group_info;
	362
	363	dprintk("NFSD: looking up %s cred\n",
	364	clnt->cl_auth->au_ops->au_name);
	365	ret = rpcauth_lookup_credcache(clnt->cl_auth, &acred, taskflags);
	366	put_group_info(clp->cl_cred.cr_group_info);
	367	return ret;
	368	}
	369
	370	/*
	371	* Set up the callback client and put a NFSPROC4_CB_NULL on the wire...
	372	*/
	373	void
	374	nfsd4_probe_callback(struct nfs4_client *clp)
	375	{
	376	struct sockaddr_in addr;
	377	struct nfs4_callback *cb = &clp->cl_callback;
	378	struct rpc_timeout timeparms;
	379	struct rpc_xprt * xprt;
	380	struct rpc_program * program = &cb->cb_program;
	381	struct rpc_stat * stat = &cb->cb_stat;
	382	struct rpc_clnt * clnt;
	383	struct rpc_message msg = {
	384	.rpc_proc = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_NULL],
	385	.rpc_argp = clp,
	386	};
	387	char hostname[32];
	388	int status;
	389
cb36d634	390	if (atomic_read(&cb->cb_set))
1da177e4 LT	391	return;
	392
	393	/* Initialize address */
	394	memset(&addr, 0, sizeof(addr));
	395	addr.sin_family = AF_INET;
	396	addr.sin_port = htons(cb->cb_port);
	397	addr.sin_addr.s_addr = htonl(cb->cb_addr);
	398
	399	/* Initialize timeout */
	400	timeparms.to_initval = (NFSD_LEASE_TIME/4) * HZ;
	401	timeparms.to_retries = 0;
	402	timeparms.to_maxval = (NFSD_LEASE_TIME/2) * HZ;
	403	timeparms.to_exponential = 1;
	404
	405	/* Create RPC transport */
f1ee4f22 N	406	xprt = xprt_create_proto(IPPROTO_TCP, &addr, &timeparms);
f1ee4f22 N	407	if (IS_ERR(xprt)) {
1da177e4 LT	408	dprintk("NFSD: couldn't create callback transport!\n");
	409	goto out_err;
	410	}
	411
	412	/* Initialize rpc_program */
	413	program->name = "nfs4_cb";
	414	program->number = cb->cb_prog;
e8c96f8c	415	program->nrvers = ARRAY_SIZE(nfs_cb_version);
1da177e4 LT	416	program->version = nfs_cb_version;
	417	program->stats = stat;
	418
	419	/* Initialize rpc_stat */
	420	memset(stat, 0, sizeof(struct rpc_stat));
	421	stat->program = program;
	422
	423	/* Create RPC client
	424	*
	425	* XXX AUTH_UNIX only - need AUTH_GSS....
	426	*/
	427	sprintf(hostname, "%u.%u.%u.%u", NIPQUAD(addr.sin_addr.s_addr));
5ba266d6	428	clnt = rpc_new_client(xprt, hostname, program, 1, RPC_AUTH_UNIX);
f1ee4f22	429	if (IS_ERR(clnt)) {
1da177e4	430	dprintk("NFSD: couldn't create callback client\n");
5b616f5d	431	goto out_err;
1da177e4 LT	432	}
	433	clnt->cl_intr = 0;
	434	clnt->cl_softrtry = 1;
1da177e4 LT	435
	436	/* Kick rpciod, put the call on the wire. */
	437
	438	if (rpciod_up() != 0) {
	439	dprintk("nfsd: couldn't start rpciod for callbacks!\n");
	440	goto out_clnt;
	441	}
	442
1da177e4	443	cb->cb_client = clnt;
541e0e09 N	444
541e0e09 N	445	/* the task holds a reference to the nfs4_client struct */
1da177e4 LT	446	atomic_inc(&clp->cl_count);
	447
	448	msg.rpc_cred = nfsd4_lookupcred(clp,0);
	449	if (IS_ERR(msg.rpc_cred))
	450	goto out_rpciod;
963d8fe5	451	status = rpc_call_async(clnt, &msg, RPC_TASK_ASYNC, &nfs4_cb_null_ops, NULL);
1da177e4 LT	452	put_rpccred(msg.rpc_cred);
	453
	454	if (status != 0) {
	455	dprintk("NFSD: asynchronous NFSPROC4_CB_NULL failed!\n");
	456	goto out_rpciod;
	457	}
	458	return;
	459
	460	out_rpciod:
	461	atomic_dec(&clp->cl_count);
	462	rpciod_down();
541e0e09	463	cb->cb_client = NULL;
1da177e4 LT	464	out_clnt:
1da177e4 LT	465	rpc_shutdown_client(clnt);
1da177e4 LT	466	out_err:
	467	dprintk("NFSD: warning: no callback path to client %.*s\n",
	468	(int)clp->cl_name.len, clp->cl_name.data);
1da177e4 LT	469	}
	470
	471	static void
963d8fe5	472	nfs4_cb_null(struct rpc_task task, void dummy)
1da177e4 LT	473	{
	474	struct nfs4_client clp = (struct nfs4_client )task->tk_msg.rpc_argp;
	475	struct nfs4_callback *cb = &clp->cl_callback;
	476	u32 addr = htonl(cb->cb_addr);
	477
	478	dprintk("NFSD: nfs4_cb_null task->tk_status %d\n", task->tk_status);
	479
	480	if (task->tk_status < 0) {
	481	dprintk("NFSD: callback establishment to client %.*s failed\n",
	482	(int)clp->cl_name.len, clp->cl_name.data);
	483	goto out;
	484	}
	485	atomic_set(&cb->cb_set, 1);
	486	dprintk("NFSD: callback set to client %u.%u.%u.%u\n", NIPQUAD(addr));
	487	out:
	488	put_nfs4_client(clp);
	489	}
	490
963d8fe5 TM	491	static const struct rpc_call_ops nfs4_cb_null_ops = {
	492	.rpc_call_done = nfs4_cb_null,
	493	};
	494
1da177e4 LT	495	/*
	496	* called with dp->dl_count inc'ed.
	497	* nfs4_lock_state() may or may not have been called.
	498	*/
	499	void
	500	nfsd4_cb_recall(struct nfs4_delegation *dp)
	501	{
	502	struct nfs4_client *clp = dp->dl_client;
	503	struct rpc_clnt *clnt = clp->cl_callback.cb_client;
	504	struct nfs4_cb_recall *cbr = &dp->dl_recall;
	505	struct rpc_message msg = {
	506	.rpc_proc = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_RECALL],
	507	.rpc_argp = cbr,
	508	};
	509	int retries = 1;
	510	int status = 0;
	511
	512	if ((!atomic_read(&clp->cl_callback.cb_set)) \|\| !clnt)
	513	return;
	514
	515	msg.rpc_cred = nfsd4_lookupcred(clp, 0);
	516	if (IS_ERR(msg.rpc_cred))
	517	goto out;
	518
	519	cbr->cbr_trunc = 0; /* XXX need to implement truncate optimization */
	520	cbr->cbr_dp = dp;
	521
	522	status = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT);
	523	while (retries--) {
	524	switch (status) {
	525	case -EIO:
	526	/* Network partition? */
	527	case -EBADHANDLE:
	528	case -NFS4ERR_BAD_STATEID:
	529	/* Race: client probably got cb_recall
	530	* before open reply granting delegation */
	531	break;
	532	default:
	533	goto out_put_cred;
	534	}
	535	ssleep(2);
	536	status = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT);
	537	}
	538	out_put_cred:
	539	put_rpccred(msg.rpc_cred);
	540	out:
	541	if (status == -EIO)
	542	atomic_set(&clp->cl_callback.cb_set, 0);
	543	/* Success or failure, now we're either waiting for lease expiration
	544	* or deleg_return. */
	545	dprintk("NFSD: nfs4_cb_recall: dp %p dl_flock %p dl_count %d\n",dp, dp->dl_flock, atomic_read(&dp->dl_count));
	546	nfs4_put_delegation(dp);
	547	return;
	548	}