[deliverable/linux.git] / fs / nfs / nfs42proc.c

/*
 * Copyright (c) 2014 Anna Schumaker <Anna.Schumaker@Netapp.com>
 */
#include <linux/fs.h>
#include <linux/sunrpc/sched.h>
#include <linux/nfs.h>
#include <linux/nfs3.h>
#include <linux/nfs4.h>
#include <linux/nfs_xdr.h>
#include <linux/nfs_fs.h>
#include "nfs4_fs.h"
#include "nfs42.h"
#include "iostat.h"
#include "pnfs.h"
#include "internal.h"

#define NFSDBG_FACILITY NFSDBG_PROC

static int nfs42_set_rw_stateid(nfs4_stateid *dst, struct file *file,
				fmode_t fmode)
{
	struct nfs_open_context *open;
	struct nfs_lock_context *lock;
	int ret;

	open = get_nfs_open_context(nfs_file_open_context(file));
	lock = nfs_get_lock_context(open);
	if (IS_ERR(lock)) {
		put_nfs_open_context(open);
		return PTR_ERR(lock);
	}

	ret = nfs4_set_rw_stateid(dst, open, lock, fmode);

	nfs_put_lock_context(lock);
	put_nfs_open_context(open);
	return ret;
}

static int _nfs42_proc_fallocate(struct rpc_message *msg, struct file *filep,
				 loff_t offset, loff_t len)
{
	struct inode *inode = file_inode(filep);
	struct nfs_server *server = NFS_SERVER(inode);
	struct nfs42_falloc_args args = {
		.falloc_fh	= NFS_FH(inode),
		.falloc_offset	= offset,
		.falloc_length	= len,
		.falloc_bitmask	= server->cache_consistency_bitmask,
	};
	struct nfs42_falloc_res res = {
		.falloc_server	= server,
	};
	int status;

	msg->rpc_argp = &args;
	msg->rpc_resp = &res;

	status = nfs42_set_rw_stateid(&args.falloc_stateid, filep, FMODE_WRITE);
	if (status)
		return status;

	res.falloc_fattr = nfs_alloc_fattr();
	if (!res.falloc_fattr)
		return -ENOMEM;

	status = nfs4_call_sync(server->client, server, msg,
				&args.seq_args, &res.seq_res, 0);
	if (status == 0)
		status = nfs_post_op_update_inode(inode, res.falloc_fattr);

	kfree(res.falloc_fattr);
	return status;
}

static int nfs42_proc_fallocate(struct rpc_message *msg, struct file *filep,
				loff_t offset, loff_t len)
{
	struct nfs_server *server = NFS_SERVER(file_inode(filep));
	struct nfs4_exception exception = { };
	int err;

	do {
		err = _nfs42_proc_fallocate(msg, filep, offset, len);
		if (err == -ENOTSUPP)
			return -EOPNOTSUPP;
		err = nfs4_handle_exception(server, err, &exception);
	} while (exception.retry);

	return err;
}

int nfs42_proc_allocate(struct file *filep, loff_t offset, loff_t len)
{
	struct rpc_message msg = {
		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_ALLOCATE],
	};
	struct inode *inode = file_inode(filep);
	int err;

	if (!nfs_server_capable(inode, NFS_CAP_ALLOCATE))
		return -EOPNOTSUPP;

	mutex_lock(&inode->i_mutex);

	err = nfs42_proc_fallocate(&msg, filep, offset, len);
	if (err == -EOPNOTSUPP)
		NFS_SERVER(inode)->caps &= ~NFS_CAP_ALLOCATE;

	mutex_unlock(&inode->i_mutex);
	return err;
}

int nfs42_proc_deallocate(struct file *filep, loff_t offset, loff_t len)
{
	struct rpc_message msg = {
		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_DEALLOCATE],
	};
	struct inode *inode = file_inode(filep);
	int err;

	if (!nfs_server_capable(inode, NFS_CAP_DEALLOCATE))
		return -EOPNOTSUPP;

	nfs_wb_all(inode);
	mutex_lock(&inode->i_mutex);

	err = nfs42_proc_fallocate(&msg, filep, offset, len);
	if (err == 0)
		truncate_pagecache_range(inode, offset, (offset + len) -1);
	if (err == -EOPNOTSUPP)
		NFS_SERVER(inode)->caps &= ~NFS_CAP_DEALLOCATE;

	mutex_unlock(&inode->i_mutex);
	return err;
}

static loff_t _nfs42_proc_llseek(struct file *filep, loff_t offset, int whence)
{
	struct inode *inode = file_inode(filep);
	struct nfs42_seek_args args = {
		.sa_fh		= NFS_FH(inode),
		.sa_offset	= offset,
		.sa_what	= (whence == SEEK_HOLE) ?
					NFS4_CONTENT_HOLE : NFS4_CONTENT_DATA,
	};
	struct nfs42_seek_res res;
	struct rpc_message msg = {
		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_SEEK],
		.rpc_argp = &args,
		.rpc_resp = &res,
	};
	struct nfs_server *server = NFS_SERVER(inode);
	int status;

	if (!nfs_server_capable(inode, NFS_CAP_SEEK))
		return -ENOTSUPP;

	status = nfs42_set_rw_stateid(&args.sa_stateid, filep, FMODE_READ);
	if (status)
		return status;

	nfs_wb_all(inode);
	status = nfs4_call_sync(server->client, server, &msg,
				&args.seq_args, &res.seq_res, 0);
	if (status == -ENOTSUPP)
		server->caps &= ~NFS_CAP_SEEK;
	if (status)
		return status;

	return vfs_setpos(filep, res.sr_offset, inode->i_sb->s_maxbytes);
}

loff_t nfs42_proc_llseek(struct file *filep, loff_t offset, int whence)
{
	struct nfs_server *server = NFS_SERVER(file_inode(filep));
	struct nfs4_exception exception = { };
	loff_t err;

	do {
		err = _nfs42_proc_llseek(filep, offset, whence);
		if (err >= 0)
			break;
		if (err == -ENOTSUPP)
			return -EOPNOTSUPP;
		err = nfs4_handle_exception(server, err, &exception);
	} while (exception.retry);

	return err;
}


static void
nfs42_layoutstat_prepare(struct rpc_task *task, void *calldata)
{
	struct nfs42_layoutstat_data *data = calldata;
	struct nfs_server *server = NFS_SERVER(data->args.inode);

	nfs41_setup_sequence(nfs4_get_session(server), &data->args.seq_args,
			     &data->res.seq_res, task);
}

static void
nfs42_layoutstat_done(struct rpc_task *task, void *calldata)
{
	struct nfs42_layoutstat_data *data = calldata;

	if (!nfs4_sequence_done(task, &data->res.seq_res))
		return;

	switch (task->tk_status) {
	case 0:
		break;
	case -ENOTSUPP:
	case -EOPNOTSUPP:
		NFS_SERVER(data->inode)->caps &= ~NFS_CAP_LAYOUTSTATS;
	default:
		dprintk("%s server returns %d\n", __func__, task->tk_status);
	}
}

static void
nfs42_layoutstat_release(void *calldata)
{
	struct nfs42_layoutstat_data *data = calldata;
	struct nfs_server *nfss = NFS_SERVER(data->args.inode);

	if (nfss->pnfs_curr_ld->cleanup_layoutstats)
		nfss->pnfs_curr_ld->cleanup_layoutstats(data);

	pnfs_put_layout_hdr(NFS_I(data->args.inode)->layout);
	smp_mb__before_atomic();
	clear_bit(NFS_INO_LAYOUTSTATS, &NFS_I(data->args.inode)->flags);
	smp_mb__after_atomic();
	nfs_iput_and_deactive(data->inode);
	kfree(data->args.devinfo);
	kfree(data);
}

static const struct rpc_call_ops nfs42_layoutstat_ops = {
	.rpc_call_prepare = nfs42_layoutstat_prepare,
	.rpc_call_done = nfs42_layoutstat_done,
	.rpc_release = nfs42_layoutstat_release,
};

int nfs42_proc_layoutstats_generic(struct nfs_server *server,
				   struct nfs42_layoutstat_data *data)
{
	struct rpc_message msg = {
		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_LAYOUTSTATS],
		.rpc_argp = &data->args,
		.rpc_resp = &data->res,
	};
	struct rpc_task_setup task_setup = {
		.rpc_client = server->client,
		.rpc_message = &msg,
		.callback_ops = &nfs42_layoutstat_ops,
		.callback_data = data,
		.flags = RPC_TASK_ASYNC,
	};
	struct rpc_task *task;

	data->inode = nfs_igrab_and_active(data->args.inode);
	if (!data->inode) {
		nfs42_layoutstat_release(data);
		return -EAGAIN;
	}
	nfs4_init_sequence(&data->args.seq_args, &data->res.seq_res, 0);
	task = rpc_run_task(&task_setup);
	if (IS_ERR(task))
		return PTR_ERR(task);
	return 0;
}

static int _nfs42_proc_clone(struct rpc_message *msg, struct file *src_f,
			     struct file *dst_f, loff_t src_offset,
			     loff_t dst_offset, loff_t count)
{
	struct inode *src_inode = file_inode(src_f);
	struct inode *dst_inode = file_inode(dst_f);
	struct nfs_server *server = NFS_SERVER(dst_inode);
	struct nfs42_clone_args args = {
		.src_fh = NFS_FH(src_inode),
		.dst_fh = NFS_FH(dst_inode),
		.src_offset = src_offset,
		.dst_offset = dst_offset,
		.count = count,
		.dst_bitmask = server->cache_consistency_bitmask,
	};
	struct nfs42_clone_res res = {
		.server	= server,
	};
	int status;

	msg->rpc_argp = &args;
	msg->rpc_resp = &res;

	status = nfs42_set_rw_stateid(&args.src_stateid, src_f, FMODE_READ);
	if (status)
		return status;

	status = nfs42_set_rw_stateid(&args.dst_stateid, dst_f, FMODE_WRITE);
	if (status)
		return status;

	res.dst_fattr = nfs_alloc_fattr();
	if (!res.dst_fattr)
		return -ENOMEM;

	status = nfs4_call_sync(server->client, server, msg,
				&args.seq_args, &res.seq_res, 0);
	if (status == 0)
		status = nfs_post_op_update_inode(dst_inode, res.dst_fattr);

	kfree(res.dst_fattr);
	return status;
}

int nfs42_proc_clone(struct file *src_f, struct file *dst_f,
		     loff_t src_offset, loff_t dst_offset, loff_t count)
{
	struct rpc_message msg = {
		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_CLONE],
	};
	struct inode *inode = file_inode(src_f);
	struct nfs_server *server = NFS_SERVER(file_inode(src_f));
	struct nfs4_exception exception = { };
	int err;

	if (!nfs_server_capable(inode, NFS_CAP_CLONE))
		return -EOPNOTSUPP;

	do {
		err = _nfs42_proc_clone(&msg, src_f, dst_f, src_offset,
					dst_offset, count);
		if (err == -ENOTSUPP || err == -EOPNOTSUPP) {
			NFS_SERVER(inode)->caps &= ~NFS_CAP_CLONE;
			return -EOPNOTSUPP;
		}
		err = nfs4_handle_exception(server, err, &exception);
	} while (exception.retry);

	return err;

}
Commit	Line	Data
1c6dcbe5 AS	1	/*
	2	* Copyright (c) 2014 Anna Schumaker <Anna.Schumaker@Netapp.com>
	3	*/
	4	#include <linux/fs.h>
	5	#include <linux/sunrpc/sched.h>
	6	#include <linux/nfs.h>
	7	#include <linux/nfs3.h>
	8	#include <linux/nfs4.h>
	9	#include <linux/nfs_xdr.h>
	10	#include <linux/nfs_fs.h>
	11	#include "nfs4_fs.h"
	12	#include "nfs42.h"
1b4a4bd8 PT	13	#include "iostat.h"
	14	#include "pnfs.h"
	15	#include "internal.h"
	16
291e1b94	17	#define NFSDBG_FACILITY NFSDBG_PROC
1c6dcbe5 AS	18
	19	static int nfs42_set_rw_stateid(nfs4_stateid dst, struct file file,
	20	fmode_t fmode)
	21	{
	22	struct nfs_open_context *open;
	23	struct nfs_lock_context *lock;
	24	int ret;
	25
	26	open = get_nfs_open_context(nfs_file_open_context(file));
	27	lock = nfs_get_lock_context(open);
	28	if (IS_ERR(lock)) {
	29	put_nfs_open_context(open);
	30	return PTR_ERR(lock);
	31	}
	32
	33	ret = nfs4_set_rw_stateid(dst, open, lock, fmode);
	34
	35	nfs_put_lock_context(lock);
	36	put_nfs_open_context(open);
	37	return ret;
	38	}
	39
f4ac1674 AS	40	static int _nfs42_proc_fallocate(struct rpc_message msg, struct file filep,
	41	loff_t offset, loff_t len)
	42	{
	43	struct inode *inode = file_inode(filep);
9a51940b	44	struct nfs_server *server = NFS_SERVER(inode);
f4ac1674 AS	45	struct nfs42_falloc_args args = {
	46	.falloc_fh = NFS_FH(inode),
	47	.falloc_offset = offset,
	48	.falloc_length = len,
9a51940b AS	49	.falloc_bitmask = server->cache_consistency_bitmask,
	50	};
	51	struct nfs42_falloc_res res = {
	52	.falloc_server = server,
f4ac1674	53	};
f4ac1674 AS	54	int status;
	55
	56	msg->rpc_argp = &args;
	57	msg->rpc_resp = &res;
	58
	59	status = nfs42_set_rw_stateid(&args.falloc_stateid, filep, FMODE_WRITE);
	60	if (status)
	61	return status;
	62
9a51940b AS	63	res.falloc_fattr = nfs_alloc_fattr();
	64	if (!res.falloc_fattr)
	65	return -ENOMEM;
	66
	67	status = nfs4_call_sync(server->client, server, msg,
	68	&args.seq_args, &res.seq_res, 0);
	69	if (status == 0)
	70	status = nfs_post_op_update_inode(inode, res.falloc_fattr);
	71
	72	kfree(res.falloc_fattr);
	73	return status;
f4ac1674 AS	74	}
	75
	76	static int nfs42_proc_fallocate(struct rpc_message msg, struct file filep,
	77	loff_t offset, loff_t len)
	78	{
	79	struct nfs_server *server = NFS_SERVER(file_inode(filep));
	80	struct nfs4_exception exception = { };
	81	int err;
	82
	83	do {
	84	err = _nfs42_proc_fallocate(msg, filep, offset, len);
	85	if (err == -ENOTSUPP)
	86	return -EOPNOTSUPP;
	87	err = nfs4_handle_exception(server, err, &exception);
	88	} while (exception.retry);
	89
	90	return err;
	91	}
	92
	93	int nfs42_proc_allocate(struct file *filep, loff_t offset, loff_t len)
	94	{
	95	struct rpc_message msg = {
	96	.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_ALLOCATE],
	97	};
	98	struct inode *inode = file_inode(filep);
	99	int err;
	100
	101	if (!nfs_server_capable(inode, NFS_CAP_ALLOCATE))
	102	return -EOPNOTSUPP;
	103
f830f7dd AS	104	mutex_lock(&inode->i_mutex);
f830f7dd AS	105
f4ac1674 AS	106	err = nfs42_proc_fallocate(&msg, filep, offset, len);
	107	if (err == -EOPNOTSUPP)
	108	NFS_SERVER(inode)->caps &= ~NFS_CAP_ALLOCATE;
f830f7dd AS	109
f830f7dd AS	110	mutex_unlock(&inode->i_mutex);
f4ac1674 AS	111	return err;
	112	}
	113
624bd5b7 AS	114	int nfs42_proc_deallocate(struct file *filep, loff_t offset, loff_t len)
	115	{
	116	struct rpc_message msg = {
	117	.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_DEALLOCATE],
	118	};
	119	struct inode *inode = file_inode(filep);
	120	int err;
	121
	122	if (!nfs_server_capable(inode, NFS_CAP_DEALLOCATE))
	123	return -EOPNOTSUPP;
	124
9a51940b	125	nfs_wb_all(inode);
f830f7dd AS	126	mutex_lock(&inode->i_mutex);
f830f7dd AS	127
624bd5b7	128	err = nfs42_proc_fallocate(&msg, filep, offset, len);
9a51940b AS	129	if (err == 0)
9a51940b AS	130	truncate_pagecache_range(inode, offset, (offset + len) -1);
624bd5b7 AS	131	if (err == -EOPNOTSUPP)
624bd5b7 AS	132	NFS_SERVER(inode)->caps &= ~NFS_CAP_DEALLOCATE;
f830f7dd AS	133
f830f7dd AS	134	mutex_unlock(&inode->i_mutex);
624bd5b7 AS	135	return err;
	136	}
	137
bdcc2cd1	138	static loff_t _nfs42_proc_llseek(struct file *filep, loff_t offset, int whence)
1c6dcbe5 AS	139	{
	140	struct inode *inode = file_inode(filep);
	141	struct nfs42_seek_args args = {
	142	.sa_fh = NFS_FH(inode),
	143	.sa_offset = offset,
	144	.sa_what = (whence == SEEK_HOLE) ?
	145	NFS4_CONTENT_HOLE : NFS4_CONTENT_DATA,
	146	};
	147	struct nfs42_seek_res res;
	148	struct rpc_message msg = {
	149	.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_SEEK],
	150	.rpc_argp = &args,
	151	.rpc_resp = &res,
	152	};
	153	struct nfs_server *server = NFS_SERVER(inode);
	154	int status;
	155
878ffa9f	156	if (!nfs_server_capable(inode, NFS_CAP_SEEK))
1c6dcbe5 AS	157	return -ENOTSUPP;
	158
	159	status = nfs42_set_rw_stateid(&args.sa_stateid, filep, FMODE_READ);
	160	if (status)
	161	return status;
	162
	163	nfs_wb_all(inode);
	164	status = nfs4_call_sync(server->client, server, &msg,
	165	&args.seq_args, &res.seq_res, 0);
	166	if (status == -ENOTSUPP)
	167	server->caps &= ~NFS_CAP_SEEK;
	168	if (status)
	169	return status;
	170
	171	return vfs_setpos(filep, res.sr_offset, inode->i_sb->s_maxbytes);
	172	}
be3a5d23	173
bdcc2cd1 BF	174	loff_t nfs42_proc_llseek(struct file *filep, loff_t offset, int whence)
	175	{
	176	struct nfs_server *server = NFS_SERVER(file_inode(filep));
	177	struct nfs4_exception exception = { };
306a5549	178	loff_t err;
bdcc2cd1 BF	179
	180	do {
	181	err = _nfs42_proc_llseek(filep, offset, whence);
306a5549 BF	182	if (err >= 0)
306a5549 BF	183	break;
bdcc2cd1 BF	184	if (err == -ENOTSUPP)
	185	return -EOPNOTSUPP;
	186	err = nfs4_handle_exception(server, err, &exception);
	187	} while (exception.retry);
	188
	189	return err;
	190	}
	191
	192
1b4a4bd8 PT	193	static void
	194	nfs42_layoutstat_prepare(struct rpc_task task, void calldata)
	195	{
	196	struct nfs42_layoutstat_data *data = calldata;
	197	struct nfs_server *server = NFS_SERVER(data->args.inode);
	198
	199	nfs41_setup_sequence(nfs4_get_session(server), &data->args.seq_args,
	200	&data->res.seq_res, task);
	201	}
	202
	203	static void
	204	nfs42_layoutstat_done(struct rpc_task task, void calldata)
	205	{
	206	struct nfs42_layoutstat_data *data = calldata;
	207
	208	if (!nfs4_sequence_done(task, &data->res.seq_res))
	209	return;
	210
6c5a0d89 TM	211	switch (task->tk_status) {
	212	case 0:
	213	break;
	214	case -ENOTSUPP:
	215	case -EOPNOTSUPP:
	216	NFS_SERVER(data->inode)->caps &= ~NFS_CAP_LAYOUTSTATS;
	217	default:
1b4a4bd8	218	dprintk("%s server returns %d\n", __func__, task->tk_status);
6c5a0d89	219	}
1b4a4bd8 PT	220	}
	221
	222	static void
	223	nfs42_layoutstat_release(void *calldata)
	224	{
	225	struct nfs42_layoutstat_data *data = calldata;
8733408d PT	226	struct nfs_server *nfss = NFS_SERVER(data->args.inode);
	227
	228	if (nfss->pnfs_curr_ld->cleanup_layoutstats)
	229	nfss->pnfs_curr_ld->cleanup_layoutstats(data);
1b4a4bd8 PT	230
1b4a4bd8 PT	231	pnfs_put_layout_hdr(NFS_I(data->args.inode)->layout);
1bfe3b25 PT	232	smp_mb__before_atomic();
	233	clear_bit(NFS_INO_LAYOUTSTATS, &NFS_I(data->args.inode)->flags);
	234	smp_mb__after_atomic();
1b4a4bd8 PT	235	nfs_iput_and_deactive(data->inode);
	236	kfree(data->args.devinfo);
	237	kfree(data);
	238	}
	239
be3a5d23	240	static const struct rpc_call_ops nfs42_layoutstat_ops = {
1b4a4bd8 PT	241	.rpc_call_prepare = nfs42_layoutstat_prepare,
	242	.rpc_call_done = nfs42_layoutstat_done,
	243	.rpc_release = nfs42_layoutstat_release,
be3a5d23 TM	244	};
	245
	246	int nfs42_proc_layoutstats_generic(struct nfs_server *server,
	247	struct nfs42_layoutstat_data *data)
	248	{
	249	struct rpc_message msg = {
	250	.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_LAYOUTSTATS],
	251	.rpc_argp = &data->args,
	252	.rpc_resp = &data->res,
	253	};
	254	struct rpc_task_setup task_setup = {
	255	.rpc_client = server->client,
	256	.rpc_message = &msg,
	257	.callback_ops = &nfs42_layoutstat_ops,
	258	.callback_data = data,
	259	.flags = RPC_TASK_ASYNC,
	260	};
	261	struct rpc_task *task;
	262
1b4a4bd8 PT	263	data->inode = nfs_igrab_and_active(data->args.inode);
	264	if (!data->inode) {
	265	nfs42_layoutstat_release(data);
	266	return -EAGAIN;
	267	}
be3a5d23 TM	268	nfs4_init_sequence(&data->args.seq_args, &data->res.seq_res, 0);
	269	task = rpc_run_task(&task_setup);
	270	if (IS_ERR(task))
	271	return PTR_ERR(task);
	272	return 0;
	273	}
e5341f3a PT	274
	275	static int _nfs42_proc_clone(struct rpc_message msg, struct file src_f,
	276	struct file *dst_f, loff_t src_offset,
	277	loff_t dst_offset, loff_t count)
	278	{
	279	struct inode *src_inode = file_inode(src_f);
	280	struct inode *dst_inode = file_inode(dst_f);
	281	struct nfs_server *server = NFS_SERVER(dst_inode);
	282	struct nfs42_clone_args args = {
	283	.src_fh = NFS_FH(src_inode),
	284	.dst_fh = NFS_FH(dst_inode),
	285	.src_offset = src_offset,
	286	.dst_offset = dst_offset,
9494b2ce	287	.count = count,
e5341f3a PT	288	.dst_bitmask = server->cache_consistency_bitmask,
	289	};
	290	struct nfs42_clone_res res = {
	291	.server = server,
	292	};
	293	int status;
	294
	295	msg->rpc_argp = &args;
	296	msg->rpc_resp = &res;
	297
	298	status = nfs42_set_rw_stateid(&args.src_stateid, src_f, FMODE_READ);
	299	if (status)
	300	return status;
	301
	302	status = nfs42_set_rw_stateid(&args.dst_stateid, dst_f, FMODE_WRITE);
	303	if (status)
	304	return status;
	305
	306	res.dst_fattr = nfs_alloc_fattr();
	307	if (!res.dst_fattr)
	308	return -ENOMEM;
	309
	310	status = nfs4_call_sync(server->client, server, msg,
	311	&args.seq_args, &res.seq_res, 0);
	312	if (status == 0)
	313	status = nfs_post_op_update_inode(dst_inode, res.dst_fattr);
	314
	315	kfree(res.dst_fattr);
	316	return status;
	317	}
	318
	319	int nfs42_proc_clone(struct file src_f, struct file dst_f,
	320	loff_t src_offset, loff_t dst_offset, loff_t count)
	321	{
	322	struct rpc_message msg = {
	323	.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_CLONE],
	324	};
	325	struct inode *inode = file_inode(src_f);
	326	struct nfs_server *server = NFS_SERVER(file_inode(src_f));
	327	struct nfs4_exception exception = { };
	328	int err;
	329
	330	if (!nfs_server_capable(inode, NFS_CAP_CLONE))
	331	return -EOPNOTSUPP;
	332
	333	do {
	334	err = _nfs42_proc_clone(&msg, src_f, dst_f, src_offset,
	335	dst_offset, count);
	336	if (err == -ENOTSUPP \|\| err == -EOPNOTSUPP) {
	337	NFS_SERVER(inode)->caps &= ~NFS_CAP_CLONE;
	338	return -EOPNOTSUPP;
	339	}
	340	err = nfs4_handle_exception(server, err, &exception);
	341	} while (exception.retry);
	342
	343	return err;
	344
	345	}