From 99c320887e23db004b80ebc536f2ade7160b7020 Mon Sep 17 00:00:00 2001 From: Dave Kleikamp Date: Fri, 29 May 2015 13:16:31 -0500 Subject: [PATCH] nfs: don't dirty kernel pages read by direct-io Replicate the logic in the commit: fd/direct-io: introduce should_dirty for kernel aio Signed-off-by: Dave Kleikamp Signed-off-by: Santosh Shilimkar --- fs/nfs/direct.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c index 38678d9a5cc4..8beeaf06e360 100644 --- a/fs/nfs/direct.c +++ b/fs/nfs/direct.c @@ -97,8 +97,11 @@ struct nfs_direct_req { struct pnfs_ds_commit_info ds_cinfo; /* Storage for cinfo */ struct work_struct work; int flags; + /* for write */ #define NFS_ODIRECT_DO_COMMIT (1) /* an unstable reply was received */ #define NFS_ODIRECT_RESCHED_WRITES (2) /* write verification failed */ + /* for read */ +#define NFS_ODIRECT_SHOULD_DIRTY (3) /* dirty user-space page after read */ struct nfs_writeverf verf; /* unstable write verifier */ }; @@ -426,7 +429,8 @@ static void nfs_direct_read_completion(struct nfs_pgio_header *hdr) struct nfs_page *req = nfs_list_entry(hdr->pages.next); struct page *page = req->wb_page; - if (!PageCompound(page) && bytes < hdr->good_bytes) + if (!PageCompound(page) && bytes < hdr->good_bytes && + (dreq->flags == NFS_ODIRECT_SHOULD_DIRTY)) set_page_dirty(page); bytes += req->wb_bytes; nfs_list_remove_request(req); @@ -608,6 +612,11 @@ ssize_t nfs_file_direct_read(struct kiocb *iocb, struct iov_iter *iter, if (!is_sync_kiocb(iocb)) dreq->iocb = iocb; + if (iter_is_iovec(iter)) + dreq->flags = NFS_ODIRECT_SHOULD_DIRTY; + else + dreq->flags = 0; + NFS_I(inode)->read_io += count; result = nfs_direct_read_schedule_iovec(dreq, iter, pos); -- 2.50.1