NFSv4.1: filelayout read

Attempt a pNFS file layout read by setting up the nfs_read_data struct and
calling nfs_initiate_read with the data server rpc client and the
filelayout rpc call ops.

Error handling is implemented in a subsequent patch.

Signed-off-by: Andy Adamson <andros@citi.umich.edu>
Signed-off-by: Dean Hildebrand <dhildeb@us.ibm.com>
Signed-off-by: Fred Isaman <iisaman@citi.umich.edu>
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Mingyang Guo <guomingyang@nrchpc.ac.cn>
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Tested-by: Guo Mingyang <guomingyang@nrchpc.ac.cn>
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This commit is contained in:
Andy Adamson 2011-03-01 01:34:19 +00:00 committed by Trond Myklebust
parent cfe7f4120f
commit dc70d7b318
6 changed files with 92 additions and 2 deletions

View File

@ -271,6 +271,8 @@ extern int nfs4_get_rootfh(struct nfs_server *server, struct nfs_fh *mntfh);
#endif
/* read.c */
extern int nfs_initiate_read(struct nfs_read_data *data, struct rpc_clnt *clnt,
const struct rpc_call_ops *call_ops);
extern void nfs_read_prepare(struct rpc_task *task, void *calldata);
/* write.c */

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@ -252,6 +252,9 @@ static inline struct nfs4_session *nfs4_get_session(const struct nfs_server *ser
extern int nfs4_setup_sequence(const struct nfs_server *server,
struct nfs4_sequence_args *args, struct nfs4_sequence_res *res,
int cache_reply, struct rpc_task *task);
extern int nfs41_setup_sequence(struct nfs4_session *session,
struct nfs4_sequence_args *args, struct nfs4_sequence_res *res,
int cache_reply, struct rpc_task *task);
extern void nfs4_destroy_session(struct nfs4_session *session);
extern struct nfs4_session *nfs4_alloc_session(struct nfs_client *clp);
extern int nfs4_proc_create_session(struct nfs_client *);

View File

@ -100,6 +100,87 @@ filelayout_get_dserver_offset(struct pnfs_layout_segment *lseg, loff_t offset)
BUG();
}
/*
* Call ops for the async read/write cases
* In the case of dense layouts, the offset needs to be reset to its
* original value.
*/
static void filelayout_read_prepare(struct rpc_task *task, void *data)
{
struct nfs_read_data *rdata = (struct nfs_read_data *)data;
if (nfs41_setup_sequence(rdata->ds_clp->cl_session,
&rdata->args.seq_args, &rdata->res.seq_res,
0, task))
return;
rpc_call_start(task);
}
static void filelayout_read_call_done(struct rpc_task *task, void *data)
{
struct nfs_read_data *rdata = (struct nfs_read_data *)data;
dprintk("--> %s task->tk_status %d\n", __func__, task->tk_status);
/* Note this may cause RPC to be resent */
rdata->mds_ops->rpc_call_done(task, data);
}
static void filelayout_read_release(void *data)
{
struct nfs_read_data *rdata = (struct nfs_read_data *)data;
rdata->mds_ops->rpc_release(data);
}
struct rpc_call_ops filelayout_read_call_ops = {
.rpc_call_prepare = filelayout_read_prepare,
.rpc_call_done = filelayout_read_call_done,
.rpc_release = filelayout_read_release,
};
static enum pnfs_try_status
filelayout_read_pagelist(struct nfs_read_data *data)
{
struct pnfs_layout_segment *lseg = data->lseg;
struct nfs4_pnfs_ds *ds;
loff_t offset = data->args.offset;
u32 j, idx;
struct nfs_fh *fh;
int status;
dprintk("--> %s ino %lu pgbase %u req %Zu@%llu\n",
__func__, data->inode->i_ino,
data->args.pgbase, (size_t)data->args.count, offset);
/* Retrieve the correct rpc_client for the byte range */
j = nfs4_fl_calc_j_index(lseg, offset);
idx = nfs4_fl_calc_ds_index(lseg, j);
ds = nfs4_fl_prepare_ds(lseg, idx);
if (!ds) {
printk(KERN_ERR "%s: prepare_ds failed, use MDS\n", __func__);
return PNFS_NOT_ATTEMPTED;
}
dprintk("%s USE DS:ip %x %hu\n", __func__,
ntohl(ds->ds_ip_addr), ntohs(ds->ds_port));
/* No multipath support. Use first DS */
data->ds_clp = ds->ds_clp;
fh = nfs4_fl_select_ds_fh(lseg, j);
if (fh)
data->args.fh = fh;
data->args.offset = filelayout_get_dserver_offset(lseg, offset);
data->mds_offset = offset;
/* Perform an asynchronous read to ds */
status = nfs_initiate_read(data, ds->ds_clp->cl_rpcclient,
&filelayout_read_call_ops);
BUG_ON(status != 0);
return PNFS_ATTEMPTED;
}
/*
* filelayout_check_layout()
*
@ -320,6 +401,7 @@ static struct pnfs_layoutdriver_type filelayout_type = {
.alloc_lseg = filelayout_alloc_lseg,
.free_lseg = filelayout_free_lseg,
.pg_test = filelayout_pg_test,
.read_pagelist = filelayout_read_pagelist,
};
static int __init nfs4filelayout_init(void)

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@ -505,7 +505,7 @@ out:
return ret_id;
}
static int nfs41_setup_sequence(struct nfs4_session *session,
int nfs41_setup_sequence(struct nfs4_session *session,
struct nfs4_sequence_args *args,
struct nfs4_sequence_res *res,
int cache_reply,
@ -571,6 +571,7 @@ static int nfs41_setup_sequence(struct nfs4_session *session,
res->sr_status = 1;
return 0;
}
EXPORT_SYMBOL_GPL(nfs41_setup_sequence);
int nfs4_setup_sequence(const struct nfs_server *server,
struct nfs4_sequence_args *args,

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@ -157,7 +157,7 @@ static void nfs_readpage_release(struct nfs_page *req)
nfs_release_request(req);
}
static int nfs_initiate_read(struct nfs_read_data *data, struct rpc_clnt *clnt,
int nfs_initiate_read(struct nfs_read_data *data, struct rpc_clnt *clnt,
const struct rpc_call_ops *call_ops)
{
struct inode *inode = data->inode;
@ -195,6 +195,7 @@ static int nfs_initiate_read(struct nfs_read_data *data, struct rpc_clnt *clnt,
rpc_put_task(task);
return 0;
}
EXPORT_SYMBOL_GPL(nfs_initiate_read);
/*
* Set up the NFS read request struct

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@ -1020,6 +1020,7 @@ struct nfs_read_data {
struct pnfs_layout_segment *lseg;
struct nfs_client *ds_clp; /* pNFS data server */
const struct rpc_call_ops *mds_ops;
__u64 mds_offset;
struct page *page_array[NFS_PAGEVEC_SIZE];
};