Commit ceb11e13 authored by Peng Tao's avatar Peng Tao Committed by Tom Haynes
Browse files

pnfs: allow LD to ask to resend read through pnfs 



If current IO cannot be completed due to some transient errors,
LD may want to ask generic layer to resend the request through
pnfs again.

Signed-off-by: default avatarPeng Tao <tao.peng@primarydata.com>
Signed-off-by: default avatarTom Haynes <loghyr@primarydata.com>
parent 48d635f1

fs/nfs/pnfs.c

+14 −1
Original line number Diff line number Diff line
@@ -1880,15 +1880,28 @@ pnfs_try_to_read_data(struct nfs_pgio_header *hdr, 
	return trypnfs;

}



/* Resend all requests through pnfs. */

int pnfs_read_resend_pnfs(struct nfs_pgio_header *hdr)

{

	struct nfs_pageio_descriptor pgio;



	nfs_pageio_init_read(&pgio, hdr->inode, false, hdr->completion_ops);

	return nfs_pageio_resend(&pgio, hdr);

}

EXPORT_SYMBOL_GPL(pnfs_read_resend_pnfs);



static void

pnfs_do_read(struct nfs_pageio_descriptor *desc, struct nfs_pgio_header *hdr)

{

	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;

	struct pnfs_layout_segment *lseg = desc->pg_lseg;

	enum pnfs_try_status trypnfs;

	int err = 0;



	trypnfs = pnfs_try_to_read_data(hdr, call_ops, lseg);

	if (trypnfs == PNFS_NOT_ATTEMPTED)

	if (trypnfs == PNFS_TRY_AGAIN)

		err = pnfs_read_resend_pnfs(hdr);

	if (trypnfs == PNFS_NOT_ATTEMPTED || err)

		pnfs_read_through_mds(desc, hdr);

}

fs/nfs/pnfs.h

+2 −0
Original line number Diff line number Diff line
@@ -72,6 +72,7 @@ struct pnfs_layout_segment { 
enum pnfs_try_status {

	PNFS_ATTEMPTED     = 0,

	PNFS_NOT_ATTEMPTED = 1,

	PNFS_TRY_AGAIN     = 2,

};



#ifdef CONFIG_NFS_V4_1
@@ -268,6 +269,7 @@ int _pnfs_return_layout(struct inode *); 
int pnfs_commit_and_return_layout(struct inode *);

void pnfs_ld_write_done(struct nfs_pgio_header *);

void pnfs_ld_read_done(struct nfs_pgio_header *);

int pnfs_read_resend_pnfs(struct nfs_pgio_header *);

struct pnfs_layout_segment *pnfs_update_layout(struct inode *ino,

					       struct nfs_open_context *ctx,

					       loff_t pos,