From ceb11e13df3e78b450730c615037133c57b90c3b Mon Sep 17 00:00:00 2001 From: Peng Tao Date: Mon, 10 Nov 2014 08:35:38 +0800 Subject: [PATCH] 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: Peng Tao Signed-off-by: Tom Haynes --- fs/nfs/pnfs.c | 15 ++++++++++++++- fs/nfs/pnfs.h | 2 ++ 2 files changed, 16 insertions(+), 1 deletion(-) diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c index b822b1749643..685af4fb39ca 100644 --- a/fs/nfs/pnfs.c +++ b/fs/nfs/pnfs.c @@ -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); } diff --git a/fs/nfs/pnfs.h b/fs/nfs/pnfs.h index a0ab81cc9cf3..84c25cd476f8 100644 --- a/fs/nfs/pnfs.h +++ b/fs/nfs/pnfs.h @@ -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, -- 2.20.1