4 files changed, 32 insertions, 8 deletions
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index ed095202942f..21f34ad0d411 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -30,6 +30,7 @@
 #include <linux/ratelimit.h>
 #include <linux/uuid.h>
 #include <linux/semaphore.h>
+#include <linux/error-injection.h>
 #include <asm/unaligned.h>
 #include "ctree.h"
 #include "disk-io.h"
@@ -3115,6 +3116,7 @@ recovery_tree_root:
 		goto fail_block_groups;
 	goto retry_root_backup;
 }
+ALLOW_ERROR_INJECTION(open_ctree, ERRNO);
 
 static void btrfs_end_buffer_write_sync(struct buffer_head *bh, int uptodate)
 {
diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index 014f3c090231..a9f22ac50d6a 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -22,6 +22,7 @@
 #include <linux/slab.h>
 #include <linux/math64.h>
 #include <linux/ratelimit.h>
+#include <linux/error-injection.h>
 #include "ctree.h"
 #include "free-space-cache.h"
 #include "transaction.h"
@@ -332,6 +333,7 @@ static int io_ctl_init(struct btrfs_io_ctl *io_ctl, struct inode *inode,
 
 	return 0;
 }
+ALLOW_ERROR_INJECTION(io_ctl_init, ERRNO);
 
 static void io_ctl_free(struct btrfs_io_ctl *io_ctl)
 {
diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index 11066d8647d2..90af87ff29ba 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -1549,16 +1549,13 @@ static void glock_hash_walk(glock_examiner examiner, const struct gfs2_sbd *sdp)
 	rhashtable_walk_enter(&gl_hash_table, &iter);
 
 	do {
-		gl = ERR_PTR(rhashtable_walk_start(&iter));
-		if (IS_ERR(gl))
-			goto walk_stop;
+		rhashtable_walk_start(&iter);
 
 		while ((gl = rhashtable_walk_next(&iter)) && !IS_ERR(gl))
 			if (gl->gl_name.ln_sbd == sdp &&
 			    lockref_get_not_dead(&gl->gl_lockref))
 				examiner(gl);
 
-walk_stop:
 		rhashtable_walk_stop(&iter);
 	} while (cond_resched(), gl == ERR_PTR(-EAGAIN));
 
@@ -1947,7 +1944,7 @@ static void *gfs2_glock_seq_start(struct seq_file *seq, loff_t *pos)
 	loff_t n = *pos;
 
 	rhashtable_walk_enter(&gl_hash_table, &gi->hti);
-	if (rhashtable_walk_start(&gi->hti) != 0)
+	if (rhashtable_walk_start_check(&gi->hti) != 0)
 		return NULL;
 
 	do {
diff --git a/fs/nsfs.c b/fs/nsfs.c
index 7c6f76d29f56..36b0772701a0 100644
--- a/fs/nsfs.c
+++ b/fs/nsfs.c
@@ -103,14 +103,14 @@ slow:
 	goto got_it;
 }
 
-void *ns_get_path(struct path *path, struct task_struct *task,
-			const struct proc_ns_operations *ns_ops)
+void *ns_get_path_cb(struct path *path, ns_get_path_helper_t *ns_get_cb,
+		     void *private_data)
 {
 	struct ns_common *ns;
 	void *ret;
 
 again:
-	ns = ns_ops->get(task);
+	ns = ns_get_cb(private_data);
 	if (!ns)
 		return ERR_PTR(-ENOENT);
 
@@ -120,6 +120,29 @@ again:
 	return ret;
 }
 
+struct ns_get_path_task_args {
+	const struct proc_ns_operations *ns_ops;
+	struct task_struct *task;
+};
+
+static struct ns_common *ns_get_path_task(void *private_data)
+{
+	struct ns_get_path_task_args *args = private_data;
+
+	return args->ns_ops->get(args->task);
+}
+
+void *ns_get_path(struct path *path, struct task_struct *task,
+		  const struct proc_ns_operations *ns_ops)
+{
+	struct ns_get_path_task_args args = {
+		.ns_ops	= ns_ops,
+		.task	= task,
+	};
+
+	return ns_get_path_cb(path, ns_get_path_task, &args);
+}
+
 int open_related_ns(struct ns_common *ns,
 		   struct ns_common *(*get_ns)(struct ns_common *ns))
 {