Use of READDIRPLUS on large directories

Commit Message

NeilBrown March 17, 2011, 12:55 a.m. UTC

None

Patch

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 2c3eb33..6882e14 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -804,6 +804,9 @@  static int nfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
 	desc->dir_cookie = &nfs_file_open_context(filp)->dir_cookie;
 	desc->decode = NFS_PROTO(inode)->decode_dirent;
 	desc->plus = NFS_USE_READDIRPLUS(inode);
+	if (filp->f_pos > 0 && !test_bit(NFS_INO_SEEN_GETATTR, &NFS_I(inode)->flags))
+		desc->plus = 0;
+	clear_bit(NFS_INO_SEEN_GETATTR, &NFS_I(inode)->flags);
 
 	nfs_block_sillyrename(dentry);
 	res = nfs_revalidate_mapping(inode, filp->f_mapping);
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 2f8e618..4cb17df 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -505,6 +505,15 @@  int nfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
 	struct inode *inode = dentry->d_inode;
 	int need_atime = NFS_I(inode)->cache_validity & NFS_INO_INVALID_ATIME;
 	int err;
+	struct dentry *p;
+	struct inode *pi;
+
+	rcu_read_lock();
+	p = dentry->d_parent;
+	pi = rcu_dereference(p)->d_inode;
+	if (pi && !test_bit(NFS_INO_SEEN_GETATTR, &NFS_I(pi)->flags))
+		set_bit(NFS_INO_SEEN_GETATTR, &NFS_I(pi)->flags);
+	rcu_read_unlock();
 
 	/* Flush out writes to the server in order to update c/mtime.  */
 	if (S_ISREG(inode->i_mode)) {
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index 6023efa..2a04ed5 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -219,6 +219,10 @@  struct nfs_inode {
 #define NFS_INO_FSCACHE		(5)		/* inode can be cached by FS-Cache */
 #define NFS_INO_FSCACHE_LOCK	(6)		/* FS-Cache cookie management lock */
 #define NFS_INO_COMMIT		(7)		/* inode is committing unstable writes */
+#define NFS_INO_SEEN_GETATTR	(8)		/* flag to track if app is calling
+						 * getattr in a directory during
+						 * readdir
+						 */
 
 static inline struct nfs_inode *NFS_I(const struct inode *inode)
 {