Commit 493292dd authored by Trond Myklebust's avatar Trond Myklebust
Browse files

NFS: Move the pnfs read code into pnfs.c 



...and ensure that we recoalese to take into account differences in
block sizes when falling back to read through the MDS.

Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
parent d9156f9f

fs/nfs/internal.h

+5 −1
Original line number Diff line number Diff line
@@ -291,14 +291,18 @@ extern struct dentry *nfs4_get_root(struct super_block *, struct nfs_fh *, 
extern int nfs4_get_rootfh(struct nfs_server *server, struct nfs_fh *mntfh);

#endif



struct nfs_pageio_descriptor;

/* 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);

extern int nfs_generic_pagein(struct nfs_pageio_descriptor *desc,

		struct list_head *head);



struct nfs_pageio_descriptor;

extern void nfs_pageio_init_read_mds(struct nfs_pageio_descriptor *pgio,

		struct inode *inode);

extern void nfs_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio);

extern void nfs_readdata_release(struct nfs_read_data *rdata);



/* write.c */

extern void nfs_pageio_init_write_mds(struct nfs_pageio_descriptor *pgio,

fs/nfs/nfs4filelayout.c

+1 −1
Original line number Diff line number Diff line
@@ -735,7 +735,7 @@ filelayout_pg_init_write(struct nfs_pageio_descriptor *pgio, 
static const struct nfs_pageio_ops filelayout_pg_read_ops = {

	.pg_init = filelayout_pg_init_read,

	.pg_test = filelayout_pg_test,

	.pg_doio = nfs_generic_pg_readpages,

	.pg_doio = pnfs_generic_pg_readpages,

};



static const struct nfs_pageio_ops filelayout_pg_write_ops = {

fs/nfs/objlayout/objio_osd.c

+1 −1
Original line number Diff line number Diff line
@@ -1007,7 +1007,7 @@ static bool objio_pg_test(struct nfs_pageio_descriptor *pgio, 
static const struct nfs_pageio_ops objio_pg_read_ops = {

	.pg_init = pnfs_generic_pg_init_read,

	.pg_test = objio_pg_test,

	.pg_doio = nfs_generic_pg_readpages,

	.pg_doio = pnfs_generic_pg_readpages,

};



static const struct nfs_pageio_ops objio_pg_write_ops = {

fs/nfs/pnfs.c

+55 −2
Original line number Diff line number Diff line
@@ -28,6 +28,7 @@ 
 */



#include <linux/nfs_fs.h>

#include <linux/nfs_page.h>

#include "internal.h"

#include "pnfs.h"

#include "iostat.h"
@@ -1216,18 +1217,32 @@ pnfs_ld_read_done(struct nfs_read_data *data) 
}

EXPORT_SYMBOL_GPL(pnfs_ld_read_done);



static void

pnfs_read_through_mds(struct nfs_pageio_descriptor *desc,

		struct nfs_read_data *data)

{

	list_splice_tail_init(&data->pages, &desc->pg_list);

	if (data->req && list_empty(&data->req->wb_list))

		nfs_list_add_request(data->req, &desc->pg_list);

	nfs_pageio_reset_read_mds(desc);

	desc->pg_recoalesce = 1;

	nfs_readdata_release(data);

}



/*

 * Call the appropriate parallel I/O subsystem read function.

 */

enum pnfs_try_status

static enum pnfs_try_status

pnfs_try_to_read_data(struct nfs_read_data *rdata,

		       const struct rpc_call_ops *call_ops)

		       const struct rpc_call_ops *call_ops,

		       struct pnfs_layout_segment *lseg)

{

	struct inode *inode = rdata->inode;

	struct nfs_server *nfss = NFS_SERVER(inode);

	enum pnfs_try_status trypnfs;



	rdata->mds_ops = call_ops;

	rdata->lseg = get_lseg(lseg);



	dprintk("%s: Reading ino:%lu %u@%llu\n",

		__func__, inode->i_ino, rdata->args.count, rdata->args.offset);
@@ -1243,6 +1258,44 @@ pnfs_try_to_read_data(struct nfs_read_data *rdata, 
	return trypnfs;

}



static void

pnfs_do_multiple_reads(struct nfs_pageio_descriptor *desc, struct list_head *head)

{

	struct nfs_read_data *data;

	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;

	struct pnfs_layout_segment *lseg = desc->pg_lseg;



	desc->pg_lseg = NULL;

	while (!list_empty(head)) {

		enum pnfs_try_status trypnfs;



		data = list_entry(head->next, struct nfs_read_data, list);

		list_del_init(&data->list);



		trypnfs = pnfs_try_to_read_data(data, call_ops, lseg);

		if (trypnfs == PNFS_NOT_ATTEMPTED)

			pnfs_read_through_mds(desc, data);

	}

	put_lseg(lseg);

}



int

pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)

{

	LIST_HEAD(head);

	int ret;



	ret = nfs_generic_pagein(desc, &head);

	if (ret != 0) {

		put_lseg(desc->pg_lseg);

		desc->pg_lseg = NULL;

		return ret;

	}

	pnfs_do_multiple_reads(desc, &head);

	return 0;

}

EXPORT_SYMBOL_GPL(pnfs_generic_pg_readpages);



/*

 * Currently there is only one (whole file) write lseg.

 */

fs/nfs/pnfs.h

+1 −9
Original line number Diff line number Diff line
@@ -157,9 +157,8 @@ void set_pnfs_layoutdriver(struct nfs_server *, u32 id); 
void unset_pnfs_layoutdriver(struct nfs_server *);

enum pnfs_try_status pnfs_try_to_write_data(struct nfs_write_data *,

					     const struct rpc_call_ops *, int);

enum pnfs_try_status pnfs_try_to_read_data(struct nfs_read_data *,

					    const struct rpc_call_ops *);

void pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *, struct nfs_page *);

int pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc);

void pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *, struct nfs_page *);

bool pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, struct nfs_page *req);

int pnfs_layout_process(struct nfs4_layoutget *lgp);
@@ -329,13 +328,6 @@ static inline void put_lseg(struct pnfs_layout_segment *lseg) 
{

}



static inline enum pnfs_try_status

pnfs_try_to_read_data(struct nfs_read_data *data,

		      const struct rpc_call_ops *call_ops)

{

	return PNFS_NOT_ATTEMPTED;

}



static inline enum pnfs_try_status

pnfs_try_to_write_data(struct nfs_write_data *data,

		       const struct rpc_call_ops *call_ops, int how)