Merge tag 'v3.15-rc1' into patchwork

Linux 3.15-rc1

* tag 'v3.15-rc1': (12180 commits)
  Linux 3.15-rc1
  mm: Initialize error in shmem_file_aio_read()
  cifs: Use min_t() when comparing "size_t" and "unsigned long"
  sym53c8xx_2: Set DID_REQUEUE return code when aborting squeue
  powerpc: Don't try to set LPCR unless we're in hypervisor mode
  futex: update documentation for ordering guarantees
  ceph: fix pr_fmt() redefinition
  vti: don't allow to add the same tunnel twice
  gre: don't allow to add the same tunnel twice
  drivers: net: xen-netfront: fix array initialization bug
  missing bits of "splice: fix racy pipe->buffers uses"
  cifs: fix the race in cifs_writev()
  ceph_sync_{,direct_}write: fix an oops on ceph_osdc_new_request() failure
  pktgen: be friendly to LLTX devices
  r8152: check RTL8152_UNPLUG
  net: sun4i-emac: add promiscuous support
  net/apne: replace IS_ERR and PTR_ERR with PTR_ERR_OR_ZERO
  blackfin: cleanup board files
  bf609: clock: drop unused clock bit set/clear functions
  Blackfin: bf537: rename "CONFIG_ADT75"
  ...

1 files changed, 27 insertions, 6 deletions

diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c
index 865f4cf9a76..c5eb2143dc6 100644
--- a/fs/btrfs/sysfs.c
+++ b/fs/btrfs/sysfs.c
@@ -24,6 +24,7 @@
 #include <linux/kobject.h>
 #include <linux/bug.h>
 #include <linux/genhd.h>
+#include <linux/debugfs.h>
 
 #include "ctree.h"
 #include "disk-io.h"
@@ -599,6 +600,12 @@ static int add_device_membership(struct btrfs_fs_info *fs_info)
 /* /sys/fs/btrfs/ entry */
 static struct kset *btrfs_kset;
 
+/* /sys/kernel/debug/btrfs */
+static struct dentry *btrfs_debugfs_root_dentry;
+
+/* Debugging tunables and exported data */
+u64 btrfs_debugfs_test;
+
 int btrfs_sysfs_add_one(struct btrfs_fs_info *fs_info)
 {
 	int error;
@@ -642,27 +649,41 @@ failure:
 	return error;
 }
 
+static int btrfs_init_debugfs(void)
+{
+#ifdef CONFIG_DEBUG_FS
+	btrfs_debugfs_root_dentry = debugfs_create_dir("btrfs", NULL);
+	if (!btrfs_debugfs_root_dentry)
+		return -ENOMEM;
+
+	debugfs_create_u64("test", S_IRUGO | S_IWUGO, btrfs_debugfs_root_dentry,
+			&btrfs_debugfs_test);
+#endif
+	return 0;
+}
+
 int btrfs_init_sysfs(void)
 {
 	int ret;
+
 	btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj);
 	if (!btrfs_kset)
 		return -ENOMEM;
 
-	init_feature_attrs();
+	ret = btrfs_init_debugfs();
+	if (ret)
+		return ret;
 
+	init_feature_attrs();
 	ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
-	if (ret) {
-		kset_unregister(btrfs_kset);
-		return ret;
-	}
 
-	return 0;
+	return ret;
 }
 
 void btrfs_exit_sysfs(void)
 {
 	sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
 	kset_unregister(btrfs_kset);
+	debugfs_remove_recursive(btrfs_debugfs_root_dentry);
 }