Merge branch 'vfs-scale-working' of git://git.kernel.org/pub/scm/linux/kernel/git/npiggin/linux-npiggin

* 'vfs-scale-working' of git://git.kernel.org/pub/scm/linux/kernel/git/npiggin/linux-npiggin: (57 commits)
  fs: scale mntget/mntput
  fs: rename vfsmount counter helpers
  fs: implement faster dentry memcmp
  fs: prefetch inode data in dcache lookup
  fs: improve scalability of pseudo filesystems
  fs: dcache per-inode inode alias locking
  fs: dcache per-bucket dcache hash locking
  bit_spinlock: add required includes
  kernel: add bl_list
  xfs: provide simple rcu-walk ACL implementation
  btrfs: provide simple rcu-walk ACL implementation
  ext2,3,4: provide simple rcu-walk ACL implementation
  fs: provide simple rcu-walk generic_check_acl implementation
  fs: provide rcu-walk aware permission i_ops
  fs: rcu-walk aware d_revalidate method
  fs: cache optimise dentry and inode for rcu-walk
  fs: dcache reduce branches in lookup path
  fs: dcache remove d_mounted
  fs: fs_struct use seqlock
  fs: rcu-walk for path lookup
  ...

1 files changed, 18 insertions, 14 deletions

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 996dd8989a91..d33da530097a 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -438,7 +438,7 @@ void nfs_prime_dcache(struct dentry *parent, struct nfs_entry *entry)
 	if (dentry == NULL)
 		return;
 
-	dentry->d_op = NFS_PROTO(dir)->dentry_ops;
+	d_set_d_op(dentry, NFS_PROTO(dir)->dentry_ops);
 	inode = nfs_fhget(dentry->d_sb, entry->fh, entry->fattr);
 	if (IS_ERR(inode))
 		goto out;
@@ -938,7 +938,8 @@ static int nfs_check_verifier(struct inode *dir, struct dentry *dentry)
  * component of the path.
  * We check for this using LOOKUP_CONTINUE and LOOKUP_PARENT.
  */
-static inline unsigned int nfs_lookup_check_intent(struct nameidata *nd, unsigned int mask)
+static inline unsigned int nfs_lookup_check_intent(struct nameidata *nd,
+						unsigned int mask)
 {
 	if (nd->flags & (LOOKUP_CONTINUE|LOOKUP_PARENT))
 		return 0;
@@ -1018,7 +1019,7 @@ int nfs_neg_need_reval(struct inode *dir, struct dentry *dentry,
  * If the parent directory is seen to have changed, we throw out the
  * cached dentry and do a new lookup.
  */
-static int nfs_lookup_revalidate(struct dentry * dentry, struct nameidata *nd)
+static int nfs_lookup_revalidate(struct dentry *dentry, struct nameidata *nd)
 {
 	struct inode *dir;
 	struct inode *inode;
@@ -1027,6 +1028,9 @@ static int nfs_lookup_revalidate(struct dentry * dentry, struct nameidata *nd)
 	struct nfs_fattr *fattr = NULL;
 	int error;
 
+	if (nd->flags & LOOKUP_RCU)
+		return -ECHILD;
+
 	parent = dget_parent(dentry);
 	dir = parent->d_inode;
 	nfs_inc_stats(dir, NFSIOS_DENTRYREVALIDATE);
@@ -1117,7 +1121,7 @@ out_error:
 /*
  * This is called from dput() when d_count is going to 0.
  */
-static int nfs_dentry_delete(struct dentry *dentry)
+static int nfs_dentry_delete(const struct dentry *dentry)
 {
 	dfprintk(VFS, "NFS: dentry_delete(%s/%s, %x)\n",
 		dentry->d_parent->d_name.name, dentry->d_name.name,
@@ -1188,7 +1192,7 @@ static struct dentry *nfs_lookup(struct inode *dir, struct dentry * dentry, stru
 	if (dentry->d_name.len > NFS_SERVER(dir)->namelen)
 		goto out;
 
-	dentry->d_op = NFS_PROTO(dir)->dentry_ops;
+	d_set_d_op(dentry, NFS_PROTO(dir)->dentry_ops);
 
 	/*
 	 * If we're doing an exclusive create, optimize away the lookup
@@ -1333,7 +1337,7 @@ static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry
 		res = ERR_PTR(-ENAMETOOLONG);
 		goto out;
 	}
-	dentry->d_op = NFS_PROTO(dir)->dentry_ops;
+	d_set_d_op(dentry, NFS_PROTO(dir)->dentry_ops);
 
 	/* Let vfs_create() deal with O_EXCL. Instantiate, but don't hash
 	 * the dentry. */
@@ -1718,11 +1722,9 @@ static int nfs_unlink(struct inode *dir, struct dentry *dentry)
 	dfprintk(VFS, "NFS: unlink(%s/%ld, %s)\n", dir->i_sb->s_id,
 		dir->i_ino, dentry->d_name.name);
 
-	spin_lock(&dcache_lock);
 	spin_lock(&dentry->d_lock);
-	if (atomic_read(&dentry->d_count) > 1) {
+	if (dentry->d_count > 1) {
 		spin_unlock(&dentry->d_lock);
-		spin_unlock(&dcache_lock);
 		/* Start asynchronous writeout of the inode */
 		write_inode_now(dentry->d_inode, 0);
 		error = nfs_sillyrename(dir, dentry);
@@ -1733,7 +1735,6 @@ static int nfs_unlink(struct inode *dir, struct dentry *dentry)
 		need_rehash = 1;
 	}
 	spin_unlock(&dentry->d_lock);
-	spin_unlock(&dcache_lock);
 	error = nfs_safe_remove(dentry);
 	if (!error || error == -ENOENT) {
 		nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
@@ -1868,7 +1869,7 @@ static int nfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 	dfprintk(VFS, "NFS: rename(%s/%s -> %s/%s, ct=%d)\n",
 		 old_dentry->d_parent->d_name.name, old_dentry->d_name.name,
 		 new_dentry->d_parent->d_name.name, new_dentry->d_name.name,
-		 atomic_read(&new_dentry->d_count));
+		 new_dentry->d_count);
 
 	/*
 	 * For non-directories, check whether the target is busy and if so,
@@ -1886,7 +1887,7 @@ static int nfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 			rehash = new_dentry;
 		}
 
-		if (atomic_read(&new_dentry->d_count) > 2) {
+		if (new_dentry->d_count > 2) {
 			int err;
 
 			/* copy the target dentry's name */
@@ -2188,11 +2189,14 @@ int nfs_may_open(struct inode *inode, struct rpc_cred *cred, int openflags)
 	return nfs_do_access(inode, cred, nfs_open_permission_mask(openflags));
 }
 
-int nfs_permission(struct inode *inode, int mask)
+int nfs_permission(struct inode *inode, int mask, unsigned int flags)
 {
 	struct rpc_cred *cred;
 	int res = 0;
 
+	if (flags & IPERM_FLAG_RCU)
+		return -ECHILD;
+
 	nfs_inc_stats(inode, NFSIOS_VFSACCESS);
 
 	if ((mask & (MAY_READ | MAY_WRITE | MAY_EXEC)) == 0)
@@ -2240,7 +2244,7 @@ out:
 out_notsup:
 	res = nfs_revalidate_inode(NFS_SERVER(inode), inode);
 	if (res == 0)
-		res = generic_permission(inode, mask, NULL);
+		res = generic_permission(inode, mask, flags, NULL);
 	goto out;
 }