[10/22] btrfs: add discard sysfs directory

Commit Message

Dennis Zhou Nov. 25, 2019, 7:46 p.m. UTC

Setup sysfs directory for discard stats + tunables.

Signed-off-by: Dennis Zhou <[e-mail]>
Reviewed-by: Josef Bacik <[e-mail]>
---
 fs/btrfs/ctree.h |  1 +
 fs/btrfs/sysfs.c | 26 ++++++++++++++++++++++++++
 2 files changed, 27 insertions(+)

Patch

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 0c5cd5e6c2c5..6a547317d26f 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -930,6 +930,7 @@  struct btrfs_fs_info {
 
 #ifdef CONFIG_BTRFS_DEBUG
 	struct kobject *debug_kobj;
+	struct kobject *discard_debug_kobj;
 #endif
 };
 
diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c
index beae5c8146fb..e877e4b3c631 100644
--- a/fs/btrfs/sysfs.c
+++ b/fs/btrfs/sysfs.c
@@ -338,6 +338,13 @@  static const struct attribute_group btrfs_static_feature_attr_group = {
 
 #ifdef CONFIG_BTRFS_DEBUG
 
+/*
+ * Discard statistics and tunables.
+ */
+static const struct attribute *discard_debug_attrs[] = {
+	NULL,
+};
+
 /*
  * Runtime debugging exported via sysfs
  *
@@ -776,6 +783,12 @@  void btrfs_sysfs_remove_mounted(struct btrfs_fs_info *fs_info)
 		kobject_put(fs_info->space_info_kobj);
 	}
 #ifdef CONFIG_BTRFS_DEBUG
+	if (fs_info->discard_debug_kobj) {
+		sysfs_remove_files(fs_info->discard_debug_kobj,
+				   discard_debug_attrs);
+		kobject_del(fs_info->discard_debug_kobj);
+		kobject_put(fs_info->discard_debug_kobj);
+	}
 	if (fs_info->debug_kobj) {
 		sysfs_remove_files(fs_info->debug_kobj,
 				   btrfs_debug_mount_attrs);
@@ -1131,6 +1144,19 @@  int btrfs_sysfs_add_mounted(struct btrfs_fs_info *fs_info)
 				   btrfs_debug_mount_attrs);
 	if (error)
 		goto failure;
+
+	/* Discard directory. */
+	fs_info->discard_debug_kobj = kobject_create_and_add("discard",
+						     fs_info->debug_kobj);
+	if (!fs_info->discard_debug_kobj) {
+		error = -ENOMEM;
+		goto failure;
+	}
+
+	error = sysfs_create_files(fs_info->discard_debug_kobj,
+				   discard_debug_attrs);
+	if (error)
+		goto failure;
 #endif
 
 	error = addrm_unknown_feature_attrs(fs_info, true);