From aa5accea404b2b92d39c1924cfeb90f6082f6389 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Fri, 27 Feb 2015 22:54:19 -0500 Subject: NFS: Ensure that buffered writes wait for O_DIRECT writes to complete The O_DIRECT code will grab the inode->i_mutex and flush out buffered writes, before scheduling a read or a write. However there is no equivalent in the buffered write code to wait for O_DIRECT to complete. Fixes a reported issue in xfstests generic/133, when first performing an O_DIRECT write followed by a buffered write. Signed-off-by: Trond Myklebust Tested-by: Chuck Lever --- fs/nfs/file.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'fs/nfs/file.c') diff --git a/fs/nfs/file.c b/fs/nfs/file.c index 94712fc781fa..c045c7169fa0 100644 --- a/fs/nfs/file.c +++ b/fs/nfs/file.c @@ -372,6 +372,10 @@ start: nfs_wait_bit_killable, TASK_KILLABLE); if (ret) return ret; + /* + * Wait for O_DIRECT to complete + */ + nfs_inode_dio_wait(mapping->host); page = grab_cache_page_write_begin(mapping, index, flags); if (!page) -- cgit v1.2.3 From 874f946376de57c8d6230b30ad71f742883fee3a Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Mon, 2 Mar 2015 23:32:08 -0500 Subject: NFS: Fix a regression in the read() syscall When invalidating the page cache for a regular file, we want to first sync all dirty data to disk and then call invalidate_inode_pages2(). The latter relies on nfs_launder_page() and nfs_release_page() to deal respectively with dirty pages, and unstable written pages. When commit 9590544694bec ("NFS: avoid deadlocks with loop-back mounted NFS filesystems.") changed the behaviour of nfs_release_page(), then it made it possible for invalidate_inode_pages2() to fail with an EBUSY. Unfortunately, that error is then propagated back to read(). Let's therefore work around the problem for now by protecting the call to sync the data and invalidate_inode_pages2() so that they are atomic w.r.t. the addition of new writes. Later on, we can revisit whether or not we still need nfs_launder_page() and nfs_release_page(). Signed-off-by: Trond Myklebust --- fs/nfs/file.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/nfs/file.c') diff --git a/fs/nfs/file.c b/fs/nfs/file.c index c045c7169fa0..41963ffca597 100644 --- a/fs/nfs/file.c +++ b/fs/nfs/file.c @@ -178,7 +178,7 @@ nfs_file_read(struct kiocb *iocb, struct iov_iter *to) iocb->ki_filp, iov_iter_count(to), (unsigned long) iocb->ki_pos); - result = nfs_revalidate_mapping(inode, iocb->ki_filp->f_mapping); + result = nfs_revalidate_mapping_protected(inode, iocb->ki_filp->f_mapping); if (!result) { result = generic_file_read_iter(iocb, to); if (result > 0) @@ -199,7 +199,7 @@ nfs_file_splice_read(struct file *filp, loff_t *ppos, dprintk("NFS: splice_read(%pD2, %lu@%Lu)\n", filp, (unsigned long) count, (unsigned long long) *ppos); - res = nfs_revalidate_mapping(inode, filp->f_mapping); + res = nfs_revalidate_mapping_protected(inode, filp->f_mapping); if (!res) { res = generic_file_splice_read(filp, ppos, pipe, count, flags); if (res > 0) -- cgit v1.2.3 From ef070dcb3989f553f5d84edf555eebc7e204099d Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Tue, 3 Mar 2015 00:06:35 -0500 Subject: NFS: Don't write enable new pages while an invalidation is proceeding nfs_vm_page_mkwrite() should wait until the page cache invalidation is finished. This is the second patch in a 2 patch series to deprecate the NFS client's reliance on nfs_release_page() in the context of nfs_invalidate_mapping(). Signed-off-by: Trond Myklebust --- fs/nfs/file.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'fs/nfs/file.c') diff --git a/fs/nfs/file.c b/fs/nfs/file.c index 41963ffca597..e679d24c39d3 100644 --- a/fs/nfs/file.c +++ b/fs/nfs/file.c @@ -623,6 +623,9 @@ static int nfs_vm_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) /* make sure the cache has finished storing the page */ nfs_fscache_wait_on_page_write(NFS_I(inode), page); + wait_on_bit_action(&NFS_I(inode)->flags, NFS_INO_INVALIDATING, + nfs_wait_bit_killable, TASK_KILLABLE); + lock_page(page); mapping = page_file_mapping(page); if (mapping != inode->i_mapping) -- cgit v1.2.3