[PATCH v2 2/5] nfs: don't dirty ITER_BVEC pages read through direct I/O
From: Omar Sandoval <osandov@osandov.com>
Date: 2014-11-21 10:08:28
Also in:
linux-btrfs, linux-fsdevel, linux-nfs, lkml
Subsystem:
filesystems (vfs and infrastructure), nfs, sunrpc, and lockd clients, the rest · Maintainers:
Alexander Viro, Christian Brauner, Trond Myklebust, Anna Schumaker, Linus Torvalds
As with the generic blockdev code, kernel pages shouldn't be dirtied by the direct I/O path. Signed-off-by: Omar Sandoval <osandov@osandov.com> --- fs/nfs/direct.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index 10bf072..a67fa2c 100644
--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c@@ -88,6 +88,7 @@ struct nfs_direct_req { struct pnfs_ds_commit_info ds_cinfo; /* Storage for cinfo */ struct work_struct work; int flags; + int should_dirty; /* should we mark read pages dirty? */ #define NFS_ODIRECT_DO_COMMIT (1) /* an unstable reply was received */ #define NFS_ODIRECT_RESCHED_WRITES (2) /* write verification failed */ struct nfs_writeverf verf; /* unstable write verifier */
@@ -370,7 +371,8 @@ 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->should_dirty) set_page_dirty(page); bytes += req->wb_bytes; nfs_list_remove_request(req);
@@ -542,6 +544,7 @@ ssize_t nfs_file_direct_read(struct kiocb *iocb, struct iov_iter *iter, dreq->inode = inode; dreq->bytes_left = count; dreq->ctx = get_nfs_open_context(nfs_file_open_context(iocb->ki_filp)); + dreq->should_dirty = !(iter->type & ITER_BVEC); l_ctx = nfs_get_lock_context(dreq->ctx); if (IS_ERR(l_ctx)) { result = PTR_ERR(l_ctx);
--
2.1.3
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