1 files changed, 889 insertions, 162 deletions

diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c
index beb7f72d50b8..1f64c132b387 100644
--- a/fs/btrfs/sysfs.c
+++ b/fs/btrfs/sysfs.c
@@ -9,8 +9,10 @@
 #include <linux/spinlock.h>
 #include <linux/completion.h>
 #include <linux/bug.h>
+#include <linux/list.h>
+#include <linux/string_choices.h>
 #include <crypto/hash.h>
-
+#include "messages.h"
 #include "ctree.h"
 #include "discard.h"
 #include "disk-io.h"
@@ -21,6 +23,10 @@
 #include "space-info.h"
 #include "block-group.h"
 #include "qgroup.h"
+#include "misc.h"
+#include "fs.h"
+#include "accessors.h"
+#include "zoned.h"
 
 /*
  * Structure name                       Path
@@ -34,12 +40,12 @@
  * qgroup_attrs				/sys/fs/btrfs/<uuid>/qgroups/<level>_<qgroupid>
  * space_info_attrs			/sys/fs/btrfs/<uuid>/allocation/<bg-type>
  * raid_attrs				/sys/fs/btrfs/<uuid>/allocation/<bg-type>/<bg-profile>
+ * discard_attrs			/sys/fs/btrfs/<uuid>/discard
  *
  * When built with BTRFS_CONFIG_DEBUG:
  *
  * btrfs_debug_feature_attrs		/sys/fs/btrfs/debug
  * btrfs_debug_mount_attrs		/sys/fs/btrfs/<uuid>/debug
- * discard_debug_attrs			/sys/fs/btrfs/<uuid>/debug/discard
  */
 
 struct btrfs_feature_attr {
@@ -61,6 +67,10 @@ struct raid_kobject {
 	.store	= _store,						\
 }
 
+#define BTRFS_ATTR_W(_prefix, _name, _store)			        \
+	static struct kobj_attribute btrfs_attr_##_prefix##_##_name =	\
+			__INIT_KOBJ_ATTR(_name, 0200, NULL, _store)
+
 #define BTRFS_ATTR_RW(_prefix, _name, _show, _store)			\
 	static struct kobj_attribute btrfs_attr_##_prefix##_##_name =	\
 			__INIT_KOBJ_ATTR(_name, 0644, _show, _store)
@@ -92,6 +102,7 @@ static struct btrfs_feature_attr btrfs_attr_features_##_name = {	     \
 
 static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj);
 static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj);
+static struct kobject *get_btrfs_kobj(struct kobject *kobj);
 
 static struct btrfs_feature_attr *to_btrfs_feature_attr(struct kobj_attribute *a)
 {
@@ -151,8 +162,7 @@ static int can_modify_feature(struct btrfs_feature_attr *fa)
 		clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
 		break;
 	default:
-		pr_warn("btrfs: sysfs: unknown feature set %d\n",
-				fa->feature_set);
+		btrfs_warn(NULL, "sysfs: unknown feature set %d", fa->feature_set);
 		return 0;
 	}
 
@@ -242,7 +252,7 @@ static ssize_t btrfs_feature_attr_store(struct kobject *kobj,
 	/*
 	 * We don't want to do full transaction commit from inside sysfs
 	 */
-	btrfs_set_pending(fs_info, COMMIT);
+	set_bit(BTRFS_FS_NEED_TRANS_COMMIT, &fs_info->flags);
 	wake_up_process(fs_info->transaction_kthread);
 
 	return count;
@@ -270,23 +280,28 @@ static umode_t btrfs_feature_visible(struct kobject *kobj,
 	return mode;
 }
 
-BTRFS_FEAT_ATTR_INCOMPAT(mixed_backref, MIXED_BACKREF);
 BTRFS_FEAT_ATTR_INCOMPAT(default_subvol, DEFAULT_SUBVOL);
 BTRFS_FEAT_ATTR_INCOMPAT(mixed_groups, MIXED_GROUPS);
 BTRFS_FEAT_ATTR_INCOMPAT(compress_lzo, COMPRESS_LZO);
 BTRFS_FEAT_ATTR_INCOMPAT(compress_zstd, COMPRESS_ZSTD);
-BTRFS_FEAT_ATTR_INCOMPAT(big_metadata, BIG_METADATA);
 BTRFS_FEAT_ATTR_INCOMPAT(extended_iref, EXTENDED_IREF);
 BTRFS_FEAT_ATTR_INCOMPAT(raid56, RAID56);
 BTRFS_FEAT_ATTR_INCOMPAT(skinny_metadata, SKINNY_METADATA);
 BTRFS_FEAT_ATTR_INCOMPAT(no_holes, NO_HOLES);
 BTRFS_FEAT_ATTR_INCOMPAT(metadata_uuid, METADATA_UUID);
 BTRFS_FEAT_ATTR_COMPAT_RO(free_space_tree, FREE_SPACE_TREE);
+BTRFS_FEAT_ATTR_COMPAT_RO(block_group_tree, BLOCK_GROUP_TREE);
 BTRFS_FEAT_ATTR_INCOMPAT(raid1c34, RAID1C34);
-/* Remove once support for zoned allocation is feature complete */
-#ifdef CONFIG_BTRFS_DEBUG
+BTRFS_FEAT_ATTR_INCOMPAT(simple_quota, SIMPLE_QUOTA);
+#ifdef CONFIG_BLK_DEV_ZONED
 BTRFS_FEAT_ATTR_INCOMPAT(zoned, ZONED);
 #endif
+#ifdef CONFIG_BTRFS_EXPERIMENTAL
+/* Remove once support for extent tree v2 is feature complete */
+BTRFS_FEAT_ATTR_INCOMPAT(extent_tree_v2, EXTENT_TREE_V2);
+/* Remove once support for raid stripe tree is feature complete. */
+BTRFS_FEAT_ATTR_INCOMPAT(raid_stripe_tree, RAID_STRIPE_TREE);
+#endif
 #ifdef CONFIG_FS_VERITY
 BTRFS_FEAT_ATTR_COMPAT_RO(verity, VERITY);
 #endif
@@ -294,17 +309,15 @@ BTRFS_FEAT_ATTR_COMPAT_RO(verity, VERITY);
 /*
  * Features which depend on feature bits and may differ between each fs.
  *
- * /sys/fs/btrfs/features      - all available features implemeted by this version
+ * /sys/fs/btrfs/features      - all available features implemented by this version
  * /sys/fs/btrfs/UUID/features - features of the fs which are enabled or
  *                               can be changed on a mounted filesystem.
  */
 static struct attribute *btrfs_supported_feature_attrs[] = {
-	BTRFS_FEAT_ATTR_PTR(mixed_backref),
 	BTRFS_FEAT_ATTR_PTR(default_subvol),
 	BTRFS_FEAT_ATTR_PTR(mixed_groups),
 	BTRFS_FEAT_ATTR_PTR(compress_lzo),
 	BTRFS_FEAT_ATTR_PTR(compress_zstd),
-	BTRFS_FEAT_ATTR_PTR(big_metadata),
 	BTRFS_FEAT_ATTR_PTR(extended_iref),
 	BTRFS_FEAT_ATTR_PTR(raid56),
 	BTRFS_FEAT_ATTR_PTR(skinny_metadata),
@@ -312,9 +325,15 @@ static struct attribute *btrfs_supported_feature_attrs[] = {
 	BTRFS_FEAT_ATTR_PTR(metadata_uuid),
 	BTRFS_FEAT_ATTR_PTR(free_space_tree),
 	BTRFS_FEAT_ATTR_PTR(raid1c34),
-#ifdef CONFIG_BTRFS_DEBUG
+	BTRFS_FEAT_ATTR_PTR(block_group_tree),
+	BTRFS_FEAT_ATTR_PTR(simple_quota),
+#ifdef CONFIG_BLK_DEV_ZONED
 	BTRFS_FEAT_ATTR_PTR(zoned),
 #endif
+#ifdef CONFIG_BTRFS_EXPERIMENTAL
+	BTRFS_FEAT_ATTR_PTR(extent_tree_v2),
+	BTRFS_FEAT_ATTR_PTR(raid_stripe_tree),
+#endif
 #ifdef CONFIG_FS_VERITY
 	BTRFS_FEAT_ATTR_PTR(verity),
 #endif
@@ -367,6 +386,8 @@ static const char *rescue_opts[] = {
 	"nologreplay",
 	"ignorebadroots",
 	"ignoredatacsums",
+	"ignoremetacsums",
+	"ignoresuperflags",
 	"all",
 };
 
@@ -390,19 +411,35 @@ static ssize_t supported_sectorsizes_show(struct kobject *kobj,
 					  char *buf)
 {
 	ssize_t ret = 0;
+	bool has_output = false;
 
-	/* 4K sector size is also supported with 64K page size */
-	if (PAGE_SIZE == SZ_64K)
-		ret += sysfs_emit_at(buf, ret, "%u ", SZ_4K);
-
-	/* Only sectorsize == PAGE_SIZE is now supported */
-	ret += sysfs_emit_at(buf, ret, "%lu\n", PAGE_SIZE);
-
+	for (u32 cur = BTRFS_MIN_BLOCKSIZE; cur <= BTRFS_MAX_BLOCKSIZE; cur *= 2) {
+		if (!btrfs_supported_blocksize(cur))
+			continue;
+		if (has_output)
+			ret += sysfs_emit_at(buf, ret, " ");
+		ret += sysfs_emit_at(buf, ret, "%u", cur);
+		has_output = true;
+	}
+	ret += sysfs_emit_at(buf, ret, "\n");
 	return ret;
 }
 BTRFS_ATTR(static_feature, supported_sectorsizes,
 	   supported_sectorsizes_show);
 
+static ssize_t acl_show(struct kobject *kobj, struct kobj_attribute *a, char *buf)
+{
+	return sysfs_emit(buf, "%d\n", IS_ENABLED(CONFIG_BTRFS_FS_POSIX_ACL));
+}
+BTRFS_ATTR(static_feature, acl, acl_show);
+
+static ssize_t temp_fsid_supported_show(struct kobject *kobj,
+					struct kobj_attribute *a, char *buf)
+{
+	return sysfs_emit(buf, "0\n");
+}
+BTRFS_ATTR(static_feature, temp_fsid, temp_fsid_supported_show);
+
 /*
  * Features which only depend on kernel version.
  *
@@ -410,11 +447,13 @@ BTRFS_ATTR(static_feature, supported_sectorsizes,
  * btrfs_supported_feature_attrs.
  */
 static struct attribute *btrfs_supported_static_feature_attrs[] = {
+	BTRFS_ATTR_PTR(static_feature, acl),
 	BTRFS_ATTR_PTR(static_feature, rmdir_subvol),
 	BTRFS_ATTR_PTR(static_feature, supported_checksums),
 	BTRFS_ATTR_PTR(static_feature, send_stream_version),
 	BTRFS_ATTR_PTR(static_feature, supported_rescue_options),
 	BTRFS_ATTR_PTR(static_feature, supported_sectorsizes),
+	BTRFS_ATTR_PTR(static_feature, temp_fsid),
 	NULL
 };
 
@@ -423,12 +462,10 @@ static const struct attribute_group btrfs_static_feature_attr_group = {
 	.attrs = btrfs_supported_static_feature_attrs,
 };
 
-#ifdef CONFIG_BTRFS_DEBUG
-
 /*
  * Discard statistics and tunables
  */
-#define discard_to_fs_info(_kobj)	to_fs_info((_kobj)->parent->parent)
+#define discard_to_fs_info(_kobj)	to_fs_info(get_btrfs_kobj(_kobj))
 
 static ssize_t btrfs_discardable_bytes_show(struct kobject *kobj,
 					    struct kobj_attribute *a,
@@ -577,11 +614,11 @@ BTRFS_ATTR_RW(discard, max_discard_size, btrfs_discard_max_discard_size_show,
 	      btrfs_discard_max_discard_size_store);
 
 /*
- * Per-filesystem debugging of discard (when mounted with discard=async).
+ * Per-filesystem stats for discard (when mounted with discard=async).
  *
- * Path: /sys/fs/btrfs/<uuid>/debug/discard/
+ * Path: /sys/fs/btrfs/<uuid>/discard/
  */
-static const struct attribute *discard_debug_attrs[] = {
+static const struct attribute *discard_attrs[] = {
 	BTRFS_ATTR_PTR(discard, discardable_bytes),
 	BTRFS_ATTR_PTR(discard, discardable_extents),
 	BTRFS_ATTR_PTR(discard, discard_bitmap_bytes),
@@ -593,6 +630,8 @@ static const struct attribute *discard_debug_attrs[] = {
 	NULL,
 };
 
+#ifdef CONFIG_BTRFS_DEBUG
+
 /*
  * Per-filesystem runtime debugging exported via sysfs.
  *
@@ -692,7 +731,7 @@ static void release_raid_kobj(struct kobject *kobj)
 	kfree(to_raid_kobj(kobj));
 }
 
-static struct kobj_type btrfs_raid_ktype = {
+static const struct kobj_type btrfs_raid_ktype = {
 	.sysfs_ops = &kobj_sysfs_ops,
 	.release = release_raid_kobj,
 	.default_groups = raid_groups,
@@ -708,6 +747,151 @@ static ssize_t btrfs_space_info_show_##field(struct kobject *kobj,	\
 }									\
 BTRFS_ATTR(space_info, field, btrfs_space_info_show_##field)
 
+static ssize_t btrfs_chunk_size_show(struct kobject *kobj,
+				     struct kobj_attribute *a, char *buf)
+{
+	struct btrfs_space_info *sinfo = to_space_info(kobj);
+
+	return sysfs_emit(buf, "%llu\n", READ_ONCE(sinfo->chunk_size));
+}
+
+/*
+ * Store new chunk size in space info. Can be called on a read-only filesystem.
+ *
+ * If the new chunk size value is larger than 10% of free space it is reduced
+ * to match that limit. Alignment must be to 256M and the system chunk size
+ * cannot be set.
+ */
+static ssize_t btrfs_chunk_size_store(struct kobject *kobj,
+				      struct kobj_attribute *a,
+				      const char *buf, size_t len)
+{
+	struct btrfs_space_info *space_info = to_space_info(kobj);
+	struct btrfs_fs_info *fs_info = to_fs_info(get_btrfs_kobj(kobj));
+	char *retptr;
+	u64 val;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	if (!fs_info->fs_devices)
+		return -EINVAL;
+
+	if (btrfs_is_zoned(fs_info))
+		return -EINVAL;
+
+	/* System block type must not be changed. */
+	if (space_info->flags & BTRFS_BLOCK_GROUP_SYSTEM)
+		return -EPERM;
+
+	val = memparse(buf, &retptr);
+	/* There could be trailing '\n', also catch any typos after the value */
+	retptr = skip_spaces(retptr);
+	if (*retptr != 0 || val == 0)
+		return -EINVAL;
+
+	val = min(val, BTRFS_MAX_DATA_CHUNK_SIZE);
+
+	/* Limit stripe size to 10% of available space. */
+	val = min(mult_perc(fs_info->fs_devices->total_rw_bytes, 10), val);
+
+	/* Must be multiple of 256M. */
+	val &= ~((u64)SZ_256M - 1);
+
+	/* Must be at least 256M. */
+	if (val < SZ_256M)
+		return -EINVAL;
+
+	btrfs_update_space_info_chunk_size(space_info, val);
+
+	return len;
+}
+
+static ssize_t btrfs_size_classes_show(struct kobject *kobj,
+				       struct kobj_attribute *a, char *buf)
+{
+	struct btrfs_space_info *sinfo = to_space_info(kobj);
+	struct btrfs_block_group *bg;
+	u32 none = 0;
+	u32 small = 0;
+	u32 medium = 0;
+	u32 large = 0;
+
+	for (int i = 0; i < BTRFS_NR_RAID_TYPES; ++i) {
+		down_read(&sinfo->groups_sem);
+		list_for_each_entry(bg, &sinfo->block_groups[i], list) {
+			if (!btrfs_block_group_should_use_size_class(bg))
+				continue;
+			switch (bg->size_class) {
+			case BTRFS_BG_SZ_NONE:
+				none++;
+				break;
+			case BTRFS_BG_SZ_SMALL:
+				small++;
+				break;
+			case BTRFS_BG_SZ_MEDIUM:
+				medium++;
+				break;
+			case BTRFS_BG_SZ_LARGE:
+				large++;
+				break;
+			}
+		}
+		up_read(&sinfo->groups_sem);
+	}
+	return sysfs_emit(buf, "none %u\n"
+			       "small %u\n"
+			       "medium %u\n"
+			       "large %u\n",
+			       none, small, medium, large);
+}
+
+#ifdef CONFIG_BTRFS_DEBUG
+/*
+ * Request chunk allocation with current chunk size.
+ */
+static ssize_t btrfs_force_chunk_alloc_store(struct kobject *kobj,
+					     struct kobj_attribute *a,
+					     const char *buf, size_t len)
+{
+	struct btrfs_space_info *space_info = to_space_info(kobj);
+	struct btrfs_fs_info *fs_info = to_fs_info(get_btrfs_kobj(kobj));
+	struct btrfs_trans_handle *trans;
+	bool val;
+	int ret;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	if (sb_rdonly(fs_info->sb))
+		return -EROFS;
+
+	ret = kstrtobool(buf, &val);
+	if (ret)
+		return ret;
+
+	if (!val)
+		return -EINVAL;
+
+	/*
+	 * This is unsafe to be called from sysfs context and may cause
+	 * unexpected problems.
+	 */
+	trans = btrfs_start_transaction(fs_info->tree_root, 0);
+	if (IS_ERR(trans))
+		return PTR_ERR(trans);
+	ret = btrfs_force_chunk_alloc(trans, space_info->flags);
+	btrfs_end_transaction(trans);
+
+	if (ret == 1)
+		return len;
+
+	return -ENOSPC;
+}
+BTRFS_ATTR_W(space_info, force_chunk_alloc, btrfs_force_chunk_alloc_store);
+
+#endif
+
 SPACE_INFO_ATTR(flags);
 SPACE_INFO_ATTR(total_bytes);
 SPACE_INFO_ATTR(bytes_used);
@@ -718,6 +902,117 @@ SPACE_INFO_ATTR(bytes_readonly);
 SPACE_INFO_ATTR(bytes_zone_unusable);
 SPACE_INFO_ATTR(disk_used);
 SPACE_INFO_ATTR(disk_total);
+SPACE_INFO_ATTR(reclaim_count);
+SPACE_INFO_ATTR(reclaim_bytes);
+SPACE_INFO_ATTR(reclaim_errors);
+BTRFS_ATTR_RW(space_info, chunk_size, btrfs_chunk_size_show, btrfs_chunk_size_store);
+BTRFS_ATTR(space_info, size_classes, btrfs_size_classes_show);
+
+static ssize_t btrfs_sinfo_bg_reclaim_threshold_show(struct kobject *kobj,
+						     struct kobj_attribute *a,
+						     char *buf)
+{
+	struct btrfs_space_info *space_info = to_space_info(kobj);
+	ssize_t ret;
+
+	spin_lock(&space_info->lock);
+	ret = sysfs_emit(buf, "%d\n", btrfs_calc_reclaim_threshold(space_info));
+	spin_unlock(&space_info->lock);
+	return ret;
+}
+
+static ssize_t btrfs_sinfo_bg_reclaim_threshold_store(struct kobject *kobj,
+						      struct kobj_attribute *a,
+						      const char *buf, size_t len)
+{
+	struct btrfs_space_info *space_info = to_space_info(kobj);
+	int thresh;
+	int ret;
+
+	if (READ_ONCE(space_info->dynamic_reclaim))
+		return -EINVAL;
+
+	ret = kstrtoint(buf, 10, &thresh);
+	if (ret)
+		return ret;
+
+	if (thresh < 0 || thresh > 100)
+		return -EINVAL;
+
+	WRITE_ONCE(space_info->bg_reclaim_threshold, thresh);
+
+	return len;
+}
+
+BTRFS_ATTR_RW(space_info, bg_reclaim_threshold,
+	      btrfs_sinfo_bg_reclaim_threshold_show,
+	      btrfs_sinfo_bg_reclaim_threshold_store);
+
+static ssize_t btrfs_sinfo_dynamic_reclaim_show(struct kobject *kobj,
+						struct kobj_attribute *a,
+						char *buf)
+{
+	struct btrfs_space_info *space_info = to_space_info(kobj);
+
+	return sysfs_emit(buf, "%d\n", READ_ONCE(space_info->dynamic_reclaim));
+}
+
+static ssize_t btrfs_sinfo_dynamic_reclaim_store(struct kobject *kobj,
+						 struct kobj_attribute *a,
+						 const char *buf, size_t len)
+{
+	struct btrfs_space_info *space_info = to_space_info(kobj);
+	int dynamic_reclaim;
+	int ret;
+
+	ret = kstrtoint(buf, 10, &dynamic_reclaim);
+	if (ret)
+		return ret;
+
+	if (dynamic_reclaim < 0)
+		return -EINVAL;
+
+	WRITE_ONCE(space_info->dynamic_reclaim, dynamic_reclaim != 0);
+
+	return len;
+}
+
+BTRFS_ATTR_RW(space_info, dynamic_reclaim,
+	      btrfs_sinfo_dynamic_reclaim_show,
+	      btrfs_sinfo_dynamic_reclaim_store);
+
+static ssize_t btrfs_sinfo_periodic_reclaim_show(struct kobject *kobj,
+						struct kobj_attribute *a,
+						char *buf)
+{
+	struct btrfs_space_info *space_info = to_space_info(kobj);
+
+	return sysfs_emit(buf, "%d\n", READ_ONCE(space_info->periodic_reclaim));
+}
+
+static ssize_t btrfs_sinfo_periodic_reclaim_store(struct kobject *kobj,
+						 struct kobj_attribute *a,
+						 const char *buf, size_t len)
+{
+	struct btrfs_space_info *space_info = to_space_info(kobj);
+	int periodic_reclaim;
+	int ret;
+
+	ret = kstrtoint(buf, 10, &periodic_reclaim);
+	if (ret)
+		return ret;
+
+	if (periodic_reclaim < 0)
+		return -EINVAL;
+
+	WRITE_ONCE(space_info->periodic_reclaim, periodic_reclaim != 0);
+
+	return len;
+}
+
+BTRFS_ATTR_RW(space_info, periodic_reclaim,
+	      btrfs_sinfo_periodic_reclaim_show,
+	      btrfs_sinfo_periodic_reclaim_store);
 
 /*
  * Allocation information about block group types.
@@ -735,6 +1030,17 @@ static struct attribute *space_info_attrs[] = {
 	BTRFS_ATTR_PTR(space_info, bytes_zone_unusable),
 	BTRFS_ATTR_PTR(space_info, disk_used),
 	BTRFS_ATTR_PTR(space_info, disk_total),
+	BTRFS_ATTR_PTR(space_info, bg_reclaim_threshold),
+	BTRFS_ATTR_PTR(space_info, dynamic_reclaim),
+	BTRFS_ATTR_PTR(space_info, chunk_size),
+	BTRFS_ATTR_PTR(space_info, size_classes),
+	BTRFS_ATTR_PTR(space_info, reclaim_count),
+	BTRFS_ATTR_PTR(space_info, reclaim_bytes),
+	BTRFS_ATTR_PTR(space_info, reclaim_errors),
+	BTRFS_ATTR_PTR(space_info, periodic_reclaim),
+#ifdef CONFIG_BTRFS_DEBUG
+	BTRFS_ATTR_PTR(space_info, force_chunk_alloc),
+#endif
 	NULL,
 };
 ATTRIBUTE_GROUPS(space_info);
@@ -745,7 +1051,7 @@ static void space_info_release(struct kobject *kobj)
 	kfree(sinfo);
 }
 
-static struct kobj_type space_info_ktype = {
+static const struct kobj_type space_info_ktype = {
 	.sysfs_ops = &kobj_sysfs_ops,
 	.release = space_info_release,
 	.default_groups = space_info_groups,
@@ -806,7 +1112,7 @@ static ssize_t btrfs_label_store(struct kobject *kobj,
 	/*
 	 * We don't want to do full transaction commit from inside sysfs
 	 */
-	btrfs_set_pending(fs_info, COMMIT);
+	set_bit(BTRFS_FS_NEED_TRANS_COMMIT, &fs_info->flags);
 	wake_up_process(fs_info->transaction_kthread);
 
 	return len;
@@ -818,7 +1124,7 @@ static ssize_t btrfs_nodesize_show(struct kobject *kobj,
 {
 	struct btrfs_fs_info *fs_info = to_fs_info(kobj);
 
-	return sysfs_emit(buf, "%u\n", fs_info->super_copy->nodesize);
+	return sysfs_emit(buf, "%u\n", fs_info->nodesize);
 }
 
 BTRFS_ATTR(, nodesize, btrfs_nodesize_show);
@@ -828,17 +1134,117 @@ static ssize_t btrfs_sectorsize_show(struct kobject *kobj,
 {
 	struct btrfs_fs_info *fs_info = to_fs_info(kobj);
 
-	return sysfs_emit(buf, "%u\n", fs_info->super_copy->sectorsize);
+	return sysfs_emit(buf, "%u\n", fs_info->sectorsize);
 }
 
 BTRFS_ATTR(, sectorsize, btrfs_sectorsize_show);
 
+static ssize_t btrfs_commit_stats_show(struct kobject *kobj,
+				       struct kobj_attribute *a, char *buf)
+{
+	struct btrfs_fs_info *fs_info = to_fs_info(kobj);
+	u64 now = ktime_get_ns();
+	u64 start_time = fs_info->commit_stats.critical_section_start_time;
+	u64 pending = 0;
+
+	if (start_time)
+		pending = now - start_time;
+
+	return sysfs_emit(buf,
+		"commits %llu\n"
+		"cur_commit_ms %llu\n"
+		"last_commit_ms %llu\n"
+		"max_commit_ms %llu\n"
+		"total_commit_ms %llu\n",
+		fs_info->commit_stats.commit_count,
+		div_u64(pending, NSEC_PER_MSEC),
+		div_u64(fs_info->commit_stats.last_commit_dur, NSEC_PER_MSEC),
+		div_u64(fs_info->commit_stats.max_commit_dur, NSEC_PER_MSEC),
+		div_u64(fs_info->commit_stats.total_commit_dur, NSEC_PER_MSEC));
+}
+
+static ssize_t btrfs_commit_stats_store(struct kobject *kobj,
+					struct kobj_attribute *a,
+					const char *buf, size_t len)
+{
+	struct btrfs_fs_info *fs_info = to_fs_info(kobj);
+	unsigned long val;
+	int ret;
+
+	if (!fs_info)
+		return -EPERM;
+
+	if (!capable(CAP_SYS_RESOURCE))
+		return -EPERM;
+
+	ret = kstrtoul(buf, 10, &val);
+	if (ret)
+		return ret;
+	if (val)
+		return -EINVAL;
+
+	WRITE_ONCE(fs_info->commit_stats.max_commit_dur, 0);
+
+	return len;
+}
+BTRFS_ATTR_RW(, commit_stats, btrfs_commit_stats_show, btrfs_commit_stats_store);
+
+static ssize_t btrfs_zoned_stats_show(struct kobject *kobj,
+				      struct kobj_attribute *a, char *buf)
+{
+	struct btrfs_fs_info *fs_info = to_fs_info(kobj);
+	struct btrfs_block_group *bg;
+	size_t ret = 0;
+
+
+	if (!btrfs_is_zoned(fs_info))
+		return ret;
+
+	spin_lock(&fs_info->zone_active_bgs_lock);
+	ret += sysfs_emit_at(buf, ret, "active block-groups: %zu\n",
+			     list_count_nodes(&fs_info->zone_active_bgs));
+	spin_unlock(&fs_info->zone_active_bgs_lock);
+
+	mutex_lock(&fs_info->reclaim_bgs_lock);
+	spin_lock(&fs_info->unused_bgs_lock);
+	ret += sysfs_emit_at(buf, ret, "\treclaimable: %zu\n",
+			     list_count_nodes(&fs_info->reclaim_bgs));
+	ret += sysfs_emit_at(buf, ret, "\tunused: %zu\n",
+			     list_count_nodes(&fs_info->unused_bgs));
+	spin_unlock(&fs_info->unused_bgs_lock);
+	mutex_unlock(&fs_info->reclaim_bgs_lock);
+
+	ret += sysfs_emit_at(buf, ret, "\tneed reclaim: %s\n",
+			     str_true_false(btrfs_zoned_should_reclaim(fs_info)));
+
+	if (fs_info->data_reloc_bg)
+		ret += sysfs_emit_at(buf, ret,
+				     "data relocation block-group: %llu\n",
+				     fs_info->data_reloc_bg);
+	if (fs_info->treelog_bg)
+		ret += sysfs_emit_at(buf, ret,
+				     "tree-log block-group: %llu\n",
+				     fs_info->treelog_bg);
+
+	spin_lock(&fs_info->zone_active_bgs_lock);
+	ret += sysfs_emit_at(buf, ret, "active zones:\n");
+	list_for_each_entry(bg, &fs_info->zone_active_bgs, active_bg_list) {
+		ret += sysfs_emit_at(buf, ret,
+				     "\tstart: %llu, wp: %llu used: %llu, reserved: %llu, unusable: %llu\n",
+				     bg->start, bg->alloc_offset, bg->used,
+				     bg->reserved, bg->zone_unusable);
+	}
+	spin_unlock(&fs_info->zone_active_bgs_lock);
+	return ret;
+}
+BTRFS_ATTR(, zoned_stats, btrfs_zoned_stats_show);
+
 static ssize_t btrfs_clone_alignment_show(struct kobject *kobj,
 				struct kobj_attribute *a, char *buf)
 {
 	struct btrfs_fs_info *fs_info = to_fs_info(kobj);
 
-	return sysfs_emit(buf, "%u\n", fs_info->super_copy->sectorsize);
+	return sysfs_emit(buf, "%u\n", fs_info->sectorsize);
 }
 
 BTRFS_ATTR(, clone_alignment, btrfs_clone_alignment_show);
@@ -859,7 +1265,7 @@ static ssize_t quota_override_store(struct kobject *kobj,
 {
 	struct btrfs_fs_info *fs_info = to_fs_info(kobj);
 	unsigned long knob;
-	int err;
+	int ret;
 
 	if (!fs_info)
 		return -EPERM;
@@ -867,9 +1273,9 @@ static ssize_t quota_override_store(struct kobject *kobj,
 	if (!capable(CAP_SYS_RESOURCE))
 		return -EPERM;
 
-	err = kstrtoul(buf, 10, &knob);
-	if (err)
-		return err;
+	ret = kstrtoul(buf, 10, &knob);
+	if (ret)
+		return ret;
 	if (knob > 1)
 		return -EINVAL;
 
@@ -919,6 +1325,9 @@ static ssize_t btrfs_exclusive_operation_show(struct kobject *kobj,
 		case BTRFS_EXCLOP_BALANCE:
 			str = "balance\n";
 			break;
+		case BTRFS_EXCLOP_BALANCE_PAUSED:
+			str = "balance paused\n";
+			break;
 		case BTRFS_EXCLOP_DEV_ADD:
 			str = "device add\n";
 			break;
@@ -947,50 +1356,119 @@ static ssize_t btrfs_generation_show(struct kobject *kobj,
 {
 	struct btrfs_fs_info *fs_info = to_fs_info(kobj);
 
-	return sysfs_emit(buf, "%llu\n", fs_info->generation);
+	return sysfs_emit(buf, "%llu\n", btrfs_get_fs_generation(fs_info));
 }
 BTRFS_ATTR(, generation, btrfs_generation_show);
 
-/*
- * Look for an exact string @string in @buffer with possible leading or
- * trailing whitespace
- */
-static bool strmatch(const char *buffer, const char *string)
+static ssize_t btrfs_temp_fsid_show(struct kobject *kobj,
+				    struct kobj_attribute *a, char *buf)
 {
-	const size_t len = strlen(string);
+	struct btrfs_fs_info *fs_info = to_fs_info(kobj);
 
-	/* Skip leading whitespace */
-	buffer = skip_spaces(buffer);
+	return sysfs_emit(buf, "%d\n", fs_info->fs_devices->temp_fsid);
+}
+BTRFS_ATTR(, temp_fsid, btrfs_temp_fsid_show);
+
+static const char *btrfs_read_policy_name[] = {
+	"pid",
+#ifdef CONFIG_BTRFS_EXPERIMENTAL
+	"round-robin",
+	"devid",
+#endif
+};
 
-	/* Match entire string, check if the rest is whitespace or empty */
-	if (strncmp(string, buffer, len) == 0 &&
-	    strlen(skip_spaces(buffer + len)) == 0)
-		return true;
+#ifdef CONFIG_BTRFS_EXPERIMENTAL
 
-	return false;
+/* Global module configuration parameters. */
+static char *read_policy;
+char *btrfs_get_mod_read_policy(void)
+{
+	return read_policy;
 }
 
-static const char * const btrfs_read_policy_name[] = { "pid" };
+/* Set perms to 0, disable /sys/module/btrfs/parameter/read_policy interface. */
+module_param(read_policy, charp, 0);
+MODULE_PARM_DESC(read_policy,
+"Global read policy: pid (default), round-robin[:<min_contig_read>], devid[:<devid>]");
+#endif
+
+int btrfs_read_policy_to_enum(const char *str, s64 *value_ret)
+{
+	char param[32];
+	char __maybe_unused *value_str;
+
+	if (!str || strlen(str) == 0)
+		return 0;
+
+	strscpy(param, str);
+
+#ifdef CONFIG_BTRFS_EXPERIMENTAL
+	/* Separate value from input in policy:value format. */
+	value_str = strchr(param, ':');
+	if (value_str) {
+		char *retptr;
+
+		*value_str = 0;
+		value_str++;
+		if (!value_ret)
+			return -EINVAL;
+
+		*value_ret = memparse(value_str, &retptr);
+		/* There could be any trailing typos after the value. */
+		retptr = skip_spaces(retptr);
+		if (*retptr != 0 || *value_ret <= 0)
+			return -EINVAL;
+	}
+#endif
+
+	return sysfs_match_string(btrfs_read_policy_name, param);
+}
+
+#ifdef CONFIG_BTRFS_EXPERIMENTAL
+int __init btrfs_read_policy_init(void)
+{
+	s64 value;
+
+	if (btrfs_read_policy_to_enum(read_policy, &value) == -EINVAL) {
+		btrfs_err(NULL, "invalid read policy or value %s", read_policy);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+#endif
 
 static ssize_t btrfs_read_policy_show(struct kobject *kobj,
 				      struct kobj_attribute *a, char *buf)
 {
 	struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj);
+	const enum btrfs_read_policy policy = READ_ONCE(fs_devices->read_policy);
 	ssize_t ret = 0;
 	int i;
 
 	for (i = 0; i < BTRFS_NR_READ_POLICY; i++) {
-		if (fs_devices->read_policy == i)
-			ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s[%s]",
-					 (ret == 0 ? "" : " "),
-					 btrfs_read_policy_name[i]);
-		else
-			ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
-					 (ret == 0 ? "" : " "),
-					 btrfs_read_policy_name[i]);
+		if (ret != 0)
+			ret += sysfs_emit_at(buf, ret, " ");
+
+		if (i == policy)
+			ret += sysfs_emit_at(buf, ret, "[");
+
+		ret += sysfs_emit_at(buf, ret, "%s", btrfs_read_policy_name[i]);
+
+#ifdef CONFIG_BTRFS_EXPERIMENTAL
+		if (i == BTRFS_READ_POLICY_RR)
+			ret += sysfs_emit_at(buf, ret, ":%u",
+					     READ_ONCE(fs_devices->rr_min_contig_read));
+
+		if (i == BTRFS_READ_POLICY_DEVID)
+			ret += sysfs_emit_at(buf, ret, ":%llu",
+					     READ_ONCE(fs_devices->read_devid));
+#endif
+		if (i == policy)
+			ret += sysfs_emit_at(buf, ret, "]");
 	}
 
-	ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
+	ret += sysfs_emit_at(buf, ret, "\n");
 
 	return ret;
 }
@@ -1000,21 +1478,80 @@ static ssize_t btrfs_read_policy_store(struct kobject *kobj,
 				       const char *buf, size_t len)
 {
 	struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj);
-	int i;
+	int index;
+	s64 value = -1;
 
-	for (i = 0; i < BTRFS_NR_READ_POLICY; i++) {
-		if (strmatch(buf, btrfs_read_policy_name[i])) {
-			if (i != fs_devices->read_policy) {
-				fs_devices->read_policy = i;
-				btrfs_info(fs_devices->fs_info,
-					   "read policy set to '%s'",
-					   btrfs_read_policy_name[i]);
+	index = btrfs_read_policy_to_enum(buf, &value);
+	if (index < 0)
+		return -EINVAL;
+
+#ifdef CONFIG_BTRFS_EXPERIMENTAL
+	/* If moving from RR then disable collecting fs stats. */
+	if (fs_devices->read_policy == BTRFS_READ_POLICY_RR && index != BTRFS_READ_POLICY_RR)
+		fs_devices->collect_fs_stats = false;
+
+	if (index == BTRFS_READ_POLICY_RR) {
+		if (value != -1) {
+			const u32 sectorsize = fs_devices->fs_info->sectorsize;
+
+			if (!IS_ALIGNED(value, sectorsize)) {
+				u64 temp_value = round_up(value, sectorsize);
+
+				btrfs_debug(fs_devices->fs_info,
+"read_policy: min contig read %lld should be multiple of sectorsize %u, rounded to %llu",
+					  value, sectorsize, temp_value);
+				value = temp_value;
 			}
-			return len;
+		} else {
+			value = BTRFS_DEFAULT_RR_MIN_CONTIG_READ;
+		}
+
+		if (index != READ_ONCE(fs_devices->read_policy) ||
+		    value != READ_ONCE(fs_devices->rr_min_contig_read)) {
+			WRITE_ONCE(fs_devices->read_policy, index);
+			WRITE_ONCE(fs_devices->rr_min_contig_read, value);
+
+			btrfs_info(fs_devices->fs_info, "read policy set to '%s:%lld'",
+				   btrfs_read_policy_name[index], value);
+		}
+
+		fs_devices->collect_fs_stats = true;
+
+		return len;
+	}
+
+	if (index == BTRFS_READ_POLICY_DEVID) {
+		if (value != -1) {
+			BTRFS_DEV_LOOKUP_ARGS(args);
+
+			/* Validate input devid. */
+			args.devid = value;
+			if (btrfs_find_device(fs_devices, &args) == NULL)
+				return -EINVAL;
+		} else {
+			/* Set default devid to the devid of the latest device. */
+			value = fs_devices->latest_dev->devid;
 		}
+
+		if (index != READ_ONCE(fs_devices->read_policy) ||
+		    value != READ_ONCE(fs_devices->read_devid)) {
+			WRITE_ONCE(fs_devices->read_policy, index);
+			WRITE_ONCE(fs_devices->read_devid, value);
+
+			btrfs_info(fs_devices->fs_info, "read policy set to '%s:%llu'",
+				   btrfs_read_policy_name[index], value);
+		}
+
+		return len;
+	}
+#endif
+	if (index != READ_ONCE(fs_devices->read_policy)) {
+		WRITE_ONCE(fs_devices->read_policy, index);
+		btrfs_info(fs_devices->fs_info, "read policy set to '%s'",
+			   btrfs_read_policy_name[index]);
 	}
 
-	return -EINVAL;
+	return len;
 }
 BTRFS_ATTR_RW(, read_policy, btrfs_read_policy_show, btrfs_read_policy_store);
 
@@ -1023,11 +1560,8 @@ static ssize_t btrfs_bg_reclaim_threshold_show(struct kobject *kobj,
 					       char *buf)
 {
 	struct btrfs_fs_info *fs_info = to_fs_info(kobj);
-	ssize_t ret;
-
-	ret = sysfs_emit(buf, "%d\n", READ_ONCE(fs_info->bg_reclaim_threshold));
 
-	return ret;
+	return sysfs_emit(buf, "%d\n", READ_ONCE(fs_info->bg_reclaim_threshold));
 }
 
 static ssize_t btrfs_bg_reclaim_threshold_store(struct kobject *kobj,
@@ -1042,8 +1576,13 @@ static ssize_t btrfs_bg_reclaim_threshold_store(struct kobject *kobj,
 	if (ret)
 		return ret;
 
+#ifdef CONFIG_BTRFS_DEBUG
+	if (thresh != 0 && (thresh > 100))
+		return -EINVAL;
+#else
 	if (thresh != 0 && (thresh <= 50 || thresh > 100))
 		return -EINVAL;
+#endif
 
 	WRITE_ONCE(fs_info->bg_reclaim_threshold, thresh);
 
@@ -1052,6 +1591,47 @@ static ssize_t btrfs_bg_reclaim_threshold_store(struct kobject *kobj,
 BTRFS_ATTR_RW(, bg_reclaim_threshold, btrfs_bg_reclaim_threshold_show,
 	      btrfs_bg_reclaim_threshold_store);
 
+#ifdef CONFIG_BTRFS_EXPERIMENTAL
+static ssize_t btrfs_offload_csum_show(struct kobject *kobj,
+				       struct kobj_attribute *a, char *buf)
+{
+	struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj);
+
+	switch (READ_ONCE(fs_devices->offload_csum_mode)) {
+	case BTRFS_OFFLOAD_CSUM_AUTO:
+		return sysfs_emit(buf, "auto\n");
+	case BTRFS_OFFLOAD_CSUM_FORCE_ON:
+		return sysfs_emit(buf, "1\n");
+	case BTRFS_OFFLOAD_CSUM_FORCE_OFF:
+		return sysfs_emit(buf, "0\n");
+	default:
+		WARN_ON(1);
+		return -EINVAL;
+	}
+}
+
+static ssize_t btrfs_offload_csum_store(struct kobject *kobj,
+					struct kobj_attribute *a, const char *buf,
+					size_t len)
+{
+	struct btrfs_fs_devices *fs_devices = to_fs_devs(kobj);
+	int ret;
+	bool val;
+
+	ret = kstrtobool(buf, &val);
+	if (ret == 0)
+		WRITE_ONCE(fs_devices->offload_csum_mode,
+			   val ? BTRFS_OFFLOAD_CSUM_FORCE_ON : BTRFS_OFFLOAD_CSUM_FORCE_OFF);
+	else if (ret == -EINVAL && sysfs_streq(buf, "auto"))
+		WRITE_ONCE(fs_devices->offload_csum_mode, BTRFS_OFFLOAD_CSUM_AUTO);
+	else
+		return -EINVAL;
+
+	return len;
+}
+BTRFS_ATTR_RW(, offload_csum, btrfs_offload_csum_show, btrfs_offload_csum_store);
+#endif
+
 /*
  * Per-filesystem information and stats.
  *
@@ -1069,6 +1649,12 @@ static const struct attribute *btrfs_attrs[] = {
 	BTRFS_ATTR_PTR(, generation),
 	BTRFS_ATTR_PTR(, read_policy),
 	BTRFS_ATTR_PTR(, bg_reclaim_threshold),
+	BTRFS_ATTR_PTR(, commit_stats),
+	BTRFS_ATTR_PTR(, temp_fsid),
+	BTRFS_ATTR_PTR(, zoned_stats),
+#ifdef CONFIG_BTRFS_EXPERIMENTAL
+	BTRFS_ATTR_PTR(, offload_csum),
+#endif
 	NULL,
 };
 
@@ -1080,7 +1666,7 @@ static void btrfs_release_fsid_kobj(struct kobject *kobj)
 	complete(&fs_devs->kobj_unregister);
 }
 
-static struct kobj_type btrfs_ktype = {
+static const struct kobj_type btrfs_ktype = {
 	.sysfs_ops	= &kobj_sysfs_ops,
 	.release	= btrfs_release_fsid_kobj,
 };
@@ -1099,11 +1685,26 @@ static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj)
 	return to_fs_devs(kobj)->fs_info;
 }
 
+static struct kobject *get_btrfs_kobj(struct kobject *kobj)
+{
+	while (kobj) {
+		if (kobj->ktype == &btrfs_ktype)
+			return kobj;
+		kobj = kobj->parent;
+	}
+	return NULL;
+}
+
 #define NUM_FEATURE_BITS 64
 #define BTRFS_FEATURE_NAME_MAX 13
 static char btrfs_unknown_feature_names[FEAT_MAX][NUM_FEATURE_BITS][BTRFS_FEATURE_NAME_MAX];
 static struct btrfs_feature_attr btrfs_feature_attrs[FEAT_MAX][NUM_FEATURE_BITS];
 
+static_assert(ARRAY_SIZE(btrfs_unknown_feature_names) ==
+	      ARRAY_SIZE(btrfs_feature_attrs));
+static_assert(ARRAY_SIZE(btrfs_unknown_feature_names[0]) ==
+	      ARRAY_SIZE(btrfs_feature_attrs[0]));
+
 static const u64 supported_feature_masks[FEAT_MAX] = {
 	[FEAT_COMPAT]    = BTRFS_FEATURE_COMPAT_SUPP,
 	[FEAT_COMPAT_RO] = BTRFS_FEATURE_COMPAT_RO_SUPP,
@@ -1212,13 +1813,12 @@ void btrfs_sysfs_remove_mounted(struct btrfs_fs_info *fs_info)
 		kobject_del(fs_info->space_info_kobj);
 		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->discard_kobj) {
+		sysfs_remove_files(fs_info->discard_kobj, discard_attrs);
+		kobject_del(fs_info->discard_kobj);
+		kobject_put(fs_info->discard_kobj);
 	}
+#ifdef CONFIG_BTRFS_DEBUG
 	if (fs_info->debug_kobj) {
 		sysfs_remove_files(fs_info->debug_kobj, btrfs_debug_mount_attrs);
 		kobject_del(fs_info->debug_kobj);
@@ -1272,11 +1872,6 @@ static void init_feature_attrs(void)
 	struct btrfs_feature_attr *fa;
 	int set, i;
 
-	BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names) !=
-		     ARRAY_SIZE(btrfs_feature_attrs));
-	BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names[0]) !=
-		     ARRAY_SIZE(btrfs_feature_attrs[0]));
-
 	memset(btrfs_feature_attrs, 0, sizeof(btrfs_feature_attrs));
 	memset(btrfs_unknown_feature_names, 0,
 	       sizeof(btrfs_unknown_feature_names));
@@ -1399,16 +1994,35 @@ void btrfs_sysfs_remove_space_info(struct btrfs_space_info *space_info)
 	kobject_put(&space_info->kobj);
 }
 
-static const char *alloc_name(u64 flags)
+static const char *alloc_name(struct btrfs_space_info *space_info)
 {
+	u64 flags = space_info->flags;
+
 	switch (flags) {
 	case BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA:
 		return "mixed";
 	case BTRFS_BLOCK_GROUP_METADATA:
-		return "metadata";
+		switch (space_info->subgroup_id) {
+		case BTRFS_SUB_GROUP_PRIMARY:
+			return "metadata";
+		case BTRFS_SUB_GROUP_TREELOG:
+			return "metadata-treelog";
+		default:
+			WARN_ON_ONCE(1);
+			return "metadata (unknown sub-group)";
+		}
 	case BTRFS_BLOCK_GROUP_DATA:
-		return "data";
+		switch (space_info->subgroup_id) {
+		case BTRFS_SUB_GROUP_PRIMARY:
+			return "data";
+		case BTRFS_SUB_GROUP_DATA_RELOC:
+			return "data-reloc";
+		default:
+			WARN_ON_ONCE(1);
+			return "data (unknown sub-group)";
+		}
 	case BTRFS_BLOCK_GROUP_SYSTEM:
+		ASSERT(space_info->subgroup_id == BTRFS_SUB_GROUP_PRIMARY);
 		return "system";
 	default:
 		WARN_ON(1);
@@ -1420,14 +2034,13 @@ static const char *alloc_name(u64 flags)
  * Create a sysfs entry for a space info type at path
  * /sys/fs/btrfs/UUID/allocation/TYPE
  */
-int btrfs_sysfs_add_space_info_type(struct btrfs_fs_info *fs_info,
-				    struct btrfs_space_info *space_info)
+int btrfs_sysfs_add_space_info_type(struct btrfs_space_info *space_info)
 {
 	int ret;
 
 	ret = kobject_init_and_add(&space_info->kobj, &space_info_ktype,
-				   fs_info->space_info_kobj, "%s",
-				   alloc_name(space_info->flags));
+				   space_info->fs_info->space_info_kobj, "%s",
+				   alloc_name(space_info));
 	if (ret) {
 		kobject_put(&space_info->kobj);
 		return ret;
@@ -1518,6 +2131,10 @@ static ssize_t btrfs_devinfo_scrub_speed_max_store(struct kobject *kobj,
 	unsigned long long limit;
 
 	limit = memparse(buf, &endptr);
+	/* There could be trailing '\n', also catch any typos after the value. */
+	endptr = skip_spaces(endptr);
+	if (*endptr != 0)
+		return -EINVAL;
 	WRITE_ONCE(device->scrub_speed_max, limit);
 	return len;
 }
@@ -1601,7 +2218,7 @@ static void btrfs_release_devid_kobj(struct kobject *kobj)
 	complete(&device->kobj_unregister);
 }
 
-static struct kobj_type devid_ktype = {
+static const struct kobj_type devid_ktype = {
 	.sysfs_ops	= &kobj_sysfs_ops,
 	.default_groups = devid_groups,
 	.release	= btrfs_release_devid_kobj,
@@ -1685,7 +2302,7 @@ void btrfs_kobject_uevent(struct block_device *bdev, enum kobject_action action)
 
 	ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action);
 	if (ret)
-		pr_warn("BTRFS: Sending event '%d' to kobject: '%s' (%p): failed\n",
+		btrfs_warn(NULL, "sending event %d to kobject: '%s' (%p): failed",
 			action, kobject_name(&disk_to_dev(bdev->bd_disk)->kobj),
 			&disk_to_dev(bdev->bd_disk)->kobj);
 }
@@ -1728,15 +2345,15 @@ static struct kset *btrfs_kset;
  */
 int btrfs_sysfs_add_fsid(struct btrfs_fs_devices *fs_devs)
 {
-	int error;
+	int ret;
 
 	init_completion(&fs_devs->kobj_unregister);
 	fs_devs->fsid_kobj.kset = btrfs_kset;
-	error = kobject_init_and_add(&fs_devs->fsid_kobj, &btrfs_ktype, NULL,
-				     "%pU", fs_devs->fsid);
-	if (error) {
+	ret = kobject_init_and_add(&fs_devs->fsid_kobj, &btrfs_ktype, NULL,
+				   "%pU", fs_devs->fsid);
+	if (ret) {
 		kobject_put(&fs_devs->fsid_kobj);
-		return error;
+		return ret;
 	}
 
 	fs_devs->devices_kobj = kobject_create_and_add("devices",
@@ -1762,75 +2379,192 @@ int btrfs_sysfs_add_fsid(struct btrfs_fs_devices *fs_devs)
 
 int btrfs_sysfs_add_mounted(struct btrfs_fs_info *fs_info)
 {
-	int error;
+	int ret;
 	struct btrfs_fs_devices *fs_devs = fs_info->fs_devices;
 	struct kobject *fsid_kobj = &fs_devs->fsid_kobj;
 
-	error = btrfs_sysfs_add_fs_devices(fs_devs);
-	if (error)
-		return error;
+	ret = btrfs_sysfs_add_fs_devices(fs_devs);
+	if (ret)
+		return ret;
 
-	error = sysfs_create_files(fsid_kobj, btrfs_attrs);
-	if (error) {
+	ret = sysfs_create_files(fsid_kobj, btrfs_attrs);
+	if (ret) {
 		btrfs_sysfs_remove_fs_devices(fs_devs);
-		return error;
+		return ret;
 	}
 
-	error = sysfs_create_group(fsid_kobj,
-				   &btrfs_feature_attr_group);
-	if (error)
+	ret = sysfs_create_group(fsid_kobj, &btrfs_feature_attr_group);
+	if (ret)
 		goto failure;
 
 #ifdef CONFIG_BTRFS_DEBUG
 	fs_info->debug_kobj = kobject_create_and_add("debug", fsid_kobj);
 	if (!fs_info->debug_kobj) {
-		error = -ENOMEM;
+		ret = -ENOMEM;
 		goto failure;
 	}
 
-	error = sysfs_create_files(fs_info->debug_kobj, btrfs_debug_mount_attrs);
-	if (error)
+	ret = sysfs_create_files(fs_info->debug_kobj, btrfs_debug_mount_attrs);
+	if (ret)
 		goto failure;
+#endif
 
 	/* Discard directory */
-	fs_info->discard_debug_kobj = kobject_create_and_add("discard",
-						     fs_info->debug_kobj);
-	if (!fs_info->discard_debug_kobj) {
-		error = -ENOMEM;
+	fs_info->discard_kobj = kobject_create_and_add("discard", fsid_kobj);
+	if (!fs_info->discard_kobj) {
+		ret = -ENOMEM;
 		goto failure;
 	}
 
-	error = sysfs_create_files(fs_info->discard_debug_kobj,
-				   discard_debug_attrs);
-	if (error)
+	ret = sysfs_create_files(fs_info->discard_kobj, discard_attrs);
+	if (ret)
 		goto failure;
-#endif
 
-	error = addrm_unknown_feature_attrs(fs_info, true);
-	if (error)
+	ret = addrm_unknown_feature_attrs(fs_info, true);
+	if (ret)
 		goto failure;
 
-	error = sysfs_create_link(fsid_kobj, &fs_info->sb->s_bdi->dev->kobj, "bdi");
-	if (error)
+	ret = sysfs_create_link(fsid_kobj, &fs_info->sb->s_bdi->dev->kobj, "bdi");
+	if (ret)
 		goto failure;
 
 	fs_info->space_info_kobj = kobject_create_and_add("allocation",
 						  fsid_kobj);
 	if (!fs_info->space_info_kobj) {
-		error = -ENOMEM;
+		ret = -ENOMEM;
 		goto failure;
 	}
 
-	error = sysfs_create_files(fs_info->space_info_kobj, allocation_attrs);
-	if (error)
+	ret = sysfs_create_files(fs_info->space_info_kobj, allocation_attrs);
+	if (ret)
 		goto failure;
 
 	return 0;
 failure:
 	btrfs_sysfs_remove_mounted(fs_info);
-	return error;
+	return ret;
+}
+
+static ssize_t qgroup_enabled_show(struct kobject *qgroups_kobj,
+				   struct kobj_attribute *a,
+				   char *buf)
+{
+	struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent);
+	bool enabled;
+
+	spin_lock(&fs_info->qgroup_lock);
+	enabled = fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON;
+	spin_unlock(&fs_info->qgroup_lock);
+
+	return sysfs_emit(buf, "%d\n", enabled);
+}
+BTRFS_ATTR(qgroups, enabled, qgroup_enabled_show);
+
+static ssize_t qgroup_mode_show(struct kobject *qgroups_kobj,
+				struct kobj_attribute *a,
+				char *buf)
+{
+	struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent);
+	ssize_t ret = 0;
+
+	spin_lock(&fs_info->qgroup_lock);
+	ASSERT(btrfs_qgroup_enabled(fs_info));
+	switch (btrfs_qgroup_mode(fs_info)) {
+	case BTRFS_QGROUP_MODE_FULL:
+		ret = sysfs_emit(buf, "qgroup\n");
+		break;
+	case BTRFS_QGROUP_MODE_SIMPLE:
+		ret = sysfs_emit(buf, "squota\n");
+		break;
+	default:
+		btrfs_warn(fs_info, "unexpected qgroup mode %d\n",
+			   btrfs_qgroup_mode(fs_info));
+		break;
+	}
+	spin_unlock(&fs_info->qgroup_lock);
+
+	return ret;
+}
+BTRFS_ATTR(qgroups, mode, qgroup_mode_show);
+
+static ssize_t qgroup_inconsistent_show(struct kobject *qgroups_kobj,
+					struct kobj_attribute *a,
+					char *buf)
+{
+	struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent);
+	bool inconsistent;
+
+	spin_lock(&fs_info->qgroup_lock);
+	inconsistent = (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT);
+	spin_unlock(&fs_info->qgroup_lock);
+
+	return sysfs_emit(buf, "%d\n", inconsistent);
+}
+BTRFS_ATTR(qgroups, inconsistent, qgroup_inconsistent_show);
+
+static ssize_t qgroup_drop_subtree_thres_show(struct kobject *qgroups_kobj,
+					      struct kobj_attribute *a,
+					      char *buf)
+{
+	struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent);
+	u8 result;
+
+	spin_lock(&fs_info->qgroup_lock);
+	result = fs_info->qgroup_drop_subtree_thres;
+	spin_unlock(&fs_info->qgroup_lock);
+
+	return sysfs_emit(buf, "%d\n", result);
 }
 
+static ssize_t qgroup_drop_subtree_thres_store(struct kobject *qgroups_kobj,
+					       struct kobj_attribute *a,
+					       const char *buf, size_t len)
+{
+	struct btrfs_fs_info *fs_info = to_fs_info(qgroups_kobj->parent);
+	u8 new_thres;
+	int ret;
+
+	ret = kstrtou8(buf, 10, &new_thres);
+	if (ret)
+		return -EINVAL;
+
+	if (new_thres > BTRFS_MAX_LEVEL)
+		return -EINVAL;
+
+	spin_lock(&fs_info->qgroup_lock);
+	fs_info->qgroup_drop_subtree_thres = new_thres;
+	spin_unlock(&fs_info->qgroup_lock);
+
+	return len;
+}
+BTRFS_ATTR_RW(qgroups, drop_subtree_threshold, qgroup_drop_subtree_thres_show,
+	      qgroup_drop_subtree_thres_store);
+
+/*
+ * Qgroups global info
+ *
+ * Path: /sys/fs/btrfs/<uuid>/qgroups/
+ */
+static struct attribute *qgroups_attrs[] = {
+	BTRFS_ATTR_PTR(qgroups, enabled),
+	BTRFS_ATTR_PTR(qgroups, inconsistent),
+	BTRFS_ATTR_PTR(qgroups, drop_subtree_threshold),
+	BTRFS_ATTR_PTR(qgroups, mode),
+	NULL
+};
+ATTRIBUTE_GROUPS(qgroups);
+
+static void qgroups_release(struct kobject *kobj)
+{
+	kfree(kobj);
+}
+
+static const struct kobj_type qgroups_ktype = {
+	.sysfs_ops = &kobj_sysfs_ops,
+	.default_groups = qgroups_groups,
+	.release = qgroups_release,
+};
+
 static inline struct btrfs_fs_info *qgroup_kobj_to_fs_info(struct kobject *kobj)
 {
 	return to_fs_info(kobj->parent->parent);
@@ -1895,7 +2629,7 @@ static void qgroup_release(struct kobject *kobj)
 	memset(&qgroup->kobj, 0, sizeof(*kobj));
 }
 
-static struct kobj_type qgroup_ktype = {
+static const struct kobj_type qgroup_ktype = {
 	.sysfs_ops = &kobj_sysfs_ops,
 	.release = qgroup_release,
 	.default_groups = qgroup_groups,
@@ -1907,7 +2641,7 @@ int btrfs_sysfs_add_one_qgroup(struct btrfs_fs_info *fs_info,
 	struct kobject *qgroups_kobj = fs_info->qgroups_kobj;
 	int ret;
 
-	if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
+	if (btrfs_is_testing(fs_info))
 		return 0;
 	if (qgroup->kobj.state_initialized)
 		return 0;
@@ -1928,7 +2662,7 @@ void btrfs_sysfs_del_qgroups(struct btrfs_fs_info *fs_info)
 	struct btrfs_qgroup *qgroup;
 	struct btrfs_qgroup *next;
 
-	if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
+	if (btrfs_is_testing(fs_info))
 		return;
 
 	rbtree_postorder_for_each_entry_safe(qgroup, next,
@@ -1949,18 +2683,22 @@ int btrfs_sysfs_add_qgroups(struct btrfs_fs_info *fs_info)
 	struct btrfs_qgroup *next;
 	int ret = 0;
 
-	if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
+	if (btrfs_is_testing(fs_info))
 		return 0;
 
 	ASSERT(fsid_kobj);
 	if (fs_info->qgroups_kobj)
 		return 0;
 
-	fs_info->qgroups_kobj = kobject_create_and_add("qgroups", fsid_kobj);
-	if (!fs_info->qgroups_kobj) {
-		ret = -ENOMEM;
+	fs_info->qgroups_kobj = kzalloc(sizeof(struct kobject), GFP_KERNEL);
+	if (!fs_info->qgroups_kobj)
+		return -ENOMEM;
+
+	ret = kobject_init_and_add(fs_info->qgroups_kobj, &qgroups_ktype,
+				   fsid_kobj, "qgroups");
+	if (ret < 0)
 		goto out;
-	}
+
 	rbtree_postorder_for_each_entry_safe(qgroup, next,
 					     &fs_info->qgroup_tree, node) {
 		ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
@@ -1977,7 +2715,7 @@ out:
 void btrfs_sysfs_del_one_qgroup(struct btrfs_fs_info *fs_info,
 				struct btrfs_qgroup *qgroup)
 {
-	if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state))
+	if (btrfs_is_testing(fs_info))
 		return;
 
 	if (qgroup->kobj.state_initialized) {
@@ -1990,36 +2728,23 @@ void btrfs_sysfs_del_one_qgroup(struct btrfs_fs_info *fs_info,
  * Change per-fs features in /sys/fs/btrfs/UUID/features to match current
  * values in superblock. Call after any changes to incompat/compat_ro flags
  */
-void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info,
-		u64 bit, enum btrfs_feature_set set)
+void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info)
 {
-	struct btrfs_fs_devices *fs_devs;
 	struct kobject *fsid_kobj;
-	u64 __maybe_unused features;
-	int __maybe_unused ret;
+	int ret;
 
 	if (!fs_info)
 		return;
 
-	/*
-	 * See 14e46e04958df74 and e410e34fad913dd, feature bit updates are not
-	 * safe when called from some contexts (eg. balance)
-	 */
-	features = get_features(fs_info, set);
-	ASSERT(bit & supported_feature_masks[set]);
-
-	fs_devs = fs_info->fs_devices;
-	fsid_kobj = &fs_devs->fsid_kobj;
-
+	fsid_kobj = &fs_info->fs_devices->fsid_kobj;
 	if (!fsid_kobj->state_initialized)
 		return;
 
-	/*
-	 * FIXME: this is too heavy to update just one value, ideally we'd like
-	 * to use sysfs_update_group but some refactoring is needed first.
-	 */
-	sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group);
-	ret = sysfs_create_group(fsid_kobj, &btrfs_feature_attr_group);
+	ret = sysfs_update_group(fsid_kobj, &btrfs_feature_attr_group);
+	if (ret < 0)
+		btrfs_warn(fs_info,
+			   "failed to update /sys/fs/btrfs/%pU/features: %d",
+			   fs_info->fs_devices->fsid, ret);
 }
 
 int __init btrfs_init_sysfs(void)
@@ -2041,8 +2766,11 @@ int __init btrfs_init_sysfs(void)
 
 #ifdef CONFIG_BTRFS_DEBUG
 	ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_debug_feature_attr_group);
-	if (ret)
-		goto out2;
+	if (ret) {
+		sysfs_unmerge_group(&btrfs_kset->kobj,
+				    &btrfs_static_feature_attr_group);
+		goto out_remove_group;
+	}
 #endif
 
 	return 0;
@@ -2065,4 +2793,3 @@ void __cold btrfs_exit_sysfs(void)
 #endif
 	kset_unregister(btrfs_kset);
 }
-