[RFC PATCH v1 13/13] NFS: Call nfs_fscache_invalidate() when write extends the size of the file

[Dave Wysochanski <dwysocha@redhat.com>]

If a write extends the size of the file and fscache is enabled, we
need to invalidate the object with the new size.  Otherwise, the next
read from the cache may fail inside cachefiles_shape_extent() due to
cookie->zero_point being smaller than the size of the file.

Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
---
 fs/nfs/write.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 005eea29e0ec..0f2f15da27f0 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -277,6 +277,7 @@ static struct nfs_page *nfs_find_and_lock_page_request(struct page *page)
 static void nfs_grow_file(struct page *page, unsigned int offset, unsigned int count)
 {
 	struct inode *inode = page_file_mapping(page)->host;
+	struct nfs_inode *nfsi = NFS_I(inode);
 	loff_t end, i_size;
 	pgoff_t end_index;
 
@@ -289,10 +290,14 @@ static void nfs_grow_file(struct page *page, unsigned int offset, unsigned int c
 	if (i_size >= end)
 		goto out;
 	i_size_write(inode, end);
-	NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_SIZE;
+	nfsi->cache_validity &= ~NFS_INO_INVALID_SIZE;
+	if (nfsi->fscache)
+		nfs_fscache_invalidate(inode);
 	nfs_inc_stats(inode, NFSIOS_EXTENDWRITE);
 out:
 	spin_unlock(&inode->i_lock);
+	dprintk("NFS:       nfs_grow_file (0x%p/0x%p) i_size=%lld\n",
+		  nfsi, nfsi->fscache, end);
 }
 
 /* A writeback failed: mark the page as bad, and invalidate the page cache */
-- 
1.8.3.1