1 files changed, 79 insertions, 76 deletions

diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 16f0673a423c..140c496f612c 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -820,55 +820,54 @@ static int nfsd_direct_splice_actor(struct pipe_inode_info *pipe,
 	return __splice_from_pipe(pipe, sd, nfsd_splice_actor);
 }
 
-static __be32
-nfsd_vfs_read(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
-              loff_t offset, struct kvec *vec, int vlen, unsigned long *count)
+__be32 nfsd_finish_read(struct file *file, unsigned long *count, int host_err)
 {
-	mm_segment_t	oldfs;
-	__be32		err;
-	int		host_err;
-
-	err = nfserr_perm;
-
-	if (file->f_op->splice_read && rqstp->rq_splice_ok) {
-		struct splice_desc sd = {
-			.len		= 0,
-			.total_len	= *count,
-			.pos		= offset,
-			.u.data		= rqstp,
-		};
-
-		rqstp->rq_next_page = rqstp->rq_respages + 1;
-		host_err = splice_direct_to_actor(file, &sd, nfsd_direct_splice_actor);
-	} else {
-		oldfs = get_fs();
-		set_fs(KERNEL_DS);
-		host_err = vfs_readv(file, (struct iovec __user *)vec, vlen, &offset);
-		set_fs(oldfs);
-	}
-
 	if (host_err >= 0) {
 		nfsdstats.io_read += host_err;
 		*count = host_err;
-		err = 0;
 		fsnotify_access(file);
+		return 0;
 	} else 
-		err = nfserrno(host_err);
-	return err;
+		return nfserrno(host_err);
+}
+
+int nfsd_splice_read(struct svc_rqst *rqstp,
+		     struct file *file, loff_t offset, unsigned long *count)
+{
+	struct splice_desc sd = {
+		.len		= 0,
+		.total_len	= *count,
+		.pos		= offset,
+		.u.data		= rqstp,
+	};
+	int host_err;
+
+	rqstp->rq_next_page = rqstp->rq_respages + 1;
+	host_err = splice_direct_to_actor(file, &sd, nfsd_direct_splice_actor);
+	return nfsd_finish_read(file, count, host_err);
 }
 
-static void kill_suid(struct dentry *dentry)
+int nfsd_readv(struct file *file, loff_t offset, struct kvec *vec, int vlen,
+		unsigned long *count)
 {
-	struct iattr	ia;
-	ia.ia_valid = ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_KILL_PRIV;
+	mm_segment_t oldfs;
+	int host_err;
 
-	mutex_lock(&dentry->d_inode->i_mutex);
-	/*
-	 * Note we call this on write, so notify_change will not
-	 * encounter any conflicting delegations:
-	 */
-	notify_change(dentry, &ia, NULL);
-	mutex_unlock(&dentry->d_inode->i_mutex);
+	oldfs = get_fs();
+	set_fs(KERNEL_DS);
+	host_err = vfs_readv(file, (struct iovec __user *)vec, vlen, &offset);
+	set_fs(oldfs);
+	return nfsd_finish_read(file, count, host_err);
+}
+
+static __be32
+nfsd_vfs_read(struct svc_rqst *rqstp, struct file *file,
+	      loff_t offset, struct kvec *vec, int vlen, unsigned long *count)
+{
+	if (file->f_op->splice_read && rqstp->rq_splice_ok)
+		return nfsd_splice_read(rqstp, file, offset, count);
+	else
+		return nfsd_readv(file, offset, vec, vlen, count);
 }
 
 /*
@@ -922,6 +921,16 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
 	int			stable = *stablep;
 	int			use_wgather;
 	loff_t			pos = offset;
+	unsigned int		pflags = current->flags;
+
+	if (rqstp->rq_local)
+		/*
+		 * We want less throttling in balance_dirty_pages()
+		 * and shrink_inactive_list() so that nfs to
+		 * localhost doesn't cause nfsd to lock up due to all
+		 * the client's dirty pages or its congested queue.
+		 */
+		current->flags |= PF_LESS_THROTTLE;
 
 	dentry = file->f_path.dentry;
 	inode = dentry->d_inode;
@@ -942,10 +951,6 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
 	nfsdstats.io_write += host_err;
 	fsnotify_modify(file);
 
-	/* clear setuid/setgid flag after write */
-	if (inode->i_mode & (S_ISUID | S_ISGID))
-		kill_suid(dentry);
-
 	if (stable) {
 		if (use_wgather)
 			host_err = wait_for_concurrent_writes(file);
@@ -959,36 +964,33 @@ out_nfserr:
 		err = 0;
 	else
 		err = nfserrno(host_err);
+	if (rqstp->rq_local)
+		tsk_restore_flags(current, pflags, PF_LESS_THROTTLE);
 	return err;
 }
 
-/*
- * Read data from a file. count must contain the requested read count
- * on entry. On return, *count contains the number of bytes actually read.
- * N.B. After this call fhp needs an fh_put
- */
-__be32 nfsd_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
-	loff_t offset, struct kvec *vec, int vlen, unsigned long *count)
+__be32 nfsd_get_tmp_read_open(struct svc_rqst *rqstp, struct svc_fh *fhp,
+		struct file **file, struct raparms **ra)
 {
-	struct file *file;
 	struct inode *inode;
-	struct raparms	*ra;
 	__be32 err;
 
-	err = nfsd_open(rqstp, fhp, S_IFREG, NFSD_MAY_READ, &file);
+	err = nfsd_open(rqstp, fhp, S_IFREG, NFSD_MAY_READ, file);
 	if (err)
 		return err;
 
-	inode = file_inode(file);
+	inode = file_inode(*file);
 
 	/* Get readahead parameters */
-	ra = nfsd_get_raparms(inode->i_sb->s_dev, inode->i_ino);
+	*ra = nfsd_get_raparms(inode->i_sb->s_dev, inode->i_ino);
 
-	if (ra && ra->p_set)
-		file->f_ra = ra->p_ra;
-
-	err = nfsd_vfs_read(rqstp, fhp, file, offset, vec, vlen, count);
+	if (*ra && (*ra)->p_set)
+		(*file)->f_ra = (*ra)->p_ra;
+	return nfs_ok;
+}
 
+void nfsd_put_tmp_read_open(struct file *file, struct raparms *ra)
+{
 	/* Write back readahead params */
 	if (ra) {
 		struct raparm_hbucket *rab = &raparm_hash[ra->p_hindex];
@@ -998,28 +1000,29 @@ __be32 nfsd_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
 		ra->p_count--;
 		spin_unlock(&rab->pb_lock);
 	}
-
 	nfsd_close(file);
-	return err;
 }
 
-/* As above, but use the provided file descriptor. */
-__be32
-nfsd_read_file(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
-		loff_t offset, struct kvec *vec, int vlen,
-		unsigned long *count)
+/*
+ * Read data from a file. count must contain the requested read count
+ * on entry. On return, *count contains the number of bytes actually read.
+ * N.B. After this call fhp needs an fh_put
+ */
+__be32 nfsd_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
+	loff_t offset, struct kvec *vec, int vlen, unsigned long *count)
 {
-	__be32		err;
+	struct file *file;
+	struct raparms	*ra;
+	__be32 err;
+
+	err = nfsd_get_tmp_read_open(rqstp, fhp, &file, &ra);
+	if (err)
+		return err;
+
+	err = nfsd_vfs_read(rqstp, file, offset, vec, vlen, count);
+
+	nfsd_put_tmp_read_open(file, ra);
 
-	if (file) {
-		err = nfsd_permission(rqstp, fhp->fh_export, fhp->fh_dentry,
-				NFSD_MAY_READ|NFSD_MAY_OWNER_OVERRIDE);
-		if (err)
-			goto out;
-		err = nfsd_vfs_read(rqstp, fhp, file, offset, vec, vlen, count);
-	} else /* Note file may still be NULL in NFSv4 special stateid case: */
-		err = nfsd_read(rqstp, fhp, offset, vec, vlen, count);
-out:
 	return err;
 }