This patch will add the following sysfs interface:
/sys/fs/btrfs/<UUID>/qgroups/<qgroup_id>/rfer
/sys/fs/btrfs/<UUID>/qgroups/<qgroup_id>/excl
/sys/fs/btrfs/<UUID>/qgroups/<qgroup_id>/max_rfer
/sys/fs/btrfs/<UUID>/qgroups/<qgroup_id>/max_excl
/sys/fs/btrfs/<UUID>/qgroups/<qgroup_id>/lim_flags
^^^ Above are already in "btrfs qgroup show" command output ^^^
/sys/fs/btrfs/<UUID>/qgroups/<qgroup_id>/rsv_data
/sys/fs/btrfs/<UUID>/qgroups/<qgroup_id>/rsv_meta_pertrans
/sys/fs/btrfs/<UUID>/qgroups/<qgroup_id>/rsv_meta_prealloc
The last 3 rsv related members are not visible to users, but can be very
useful to debug qgroup limit related bugs.
Also, to avoid '/' used in <qgroup_id>, the seperator between qgroup
level and qgroup id is changed to '_'.
The interface is not hidden behind 'debug' as I want this interface to
be included into production build so we could have an easier life to
debug qgroup rsv related bugs.
Signed-off-by: Qu Wenruo <wqu@xxxxxxxx>
---
fs/btrfs/ctree.h | 1 +
fs/btrfs/qgroup.c | 38 ++++++++----
fs/btrfs/qgroup.h | 12 ++++
fs/btrfs/sysfs.c | 149 ++++++++++++++++++++++++++++++++++++++++++++++
fs/btrfs/sysfs.h | 6 ++
5 files changed, 194 insertions(+), 12 deletions(-)
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index d8301bf240e0..7576dfe39841 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -779,6 +779,7 @@ struct btrfs_fs_info {
u32 thread_pool_size;
struct kobject *space_info_kobj;
+ struct kobject *qgroup_kobj;
u64 total_pinned;
diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index 74eb98479109..04fdd42f0eb5 100644
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -22,6 +22,7 @@
#include "extent_io.h"
#include "qgroup.h"
#include "block-group.h"
+#include "sysfs.h"
/* TODO XXX FIXME
* - subvol delete -> delete when ref goes to 0? delete limits also?
@@ -192,38 +193,47 @@ static struct btrfs_qgroup *add_qgroup_rb(struct btrfs_fs_info *fs_info,
struct rb_node **p = &fs_info->qgroup_tree.rb_node;
struct rb_node *parent = NULL;
struct btrfs_qgroup *qgroup;
+ int ret;
while (*p) {
parent = *p;
qgroup = rb_entry(parent, struct btrfs_qgroup, node);
- if (qgroup->qgroupid < qgroupid)
+ if (qgroup->qgroupid < qgroupid) {
p = &(*p)->rb_left;
- else if (qgroup->qgroupid > qgroupid)
+ } else if (qgroup->qgroupid > qgroupid) {
p = &(*p)->rb_right;
- else
+ } else {
return qgroup;
+ }
}
qgroup = kzalloc(sizeof(*qgroup), GFP_ATOMIC);
if (!qgroup)
return ERR_PTR(-ENOMEM);
-
qgroup->qgroupid = qgroupid;
INIT_LIST_HEAD(&qgroup->groups);
INIT_LIST_HEAD(&qgroup->members);
INIT_LIST_HEAD(&qgroup->dirty);
+ ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
+ if (ret < 0) {
+ kfree(qgroup);
+ return ERR_PTR(ret);
+ }
+
rb_link_node(&qgroup->node, parent, p);
rb_insert_color(&qgroup->node, &fs_info->qgroup_tree);
return qgroup;
}
-static void __del_qgroup_rb(struct btrfs_qgroup *qgroup)
+static void __del_qgroup_rb(struct btrfs_fs_info *fs_info,
+ struct btrfs_qgroup *qgroup)
{
struct btrfs_qgroup_list *list;
+ btrfs_sysfs_del_one_qgroup(fs_info, qgroup);
list_del(&qgroup->dirty);
while (!list_empty(&qgroup->groups)) {
list = list_first_entry(&qgroup->groups,
@@ -252,7 +262,7 @@ static int del_qgroup_rb(struct btrfs_fs_info *fs_info, u64 qgroupid)
return -ENOENT;
rb_erase(&qgroup->node, &fs_info->qgroup_tree);
- __del_qgroup_rb(qgroup);
+ __del_qgroup_rb(fs_info, qgroup);
return 0;
}
@@ -351,6 +361,9 @@ int btrfs_read_qgroup_config(struct btrfs_fs_info *fs_info)
goto out;
}
+ ret = btrfs_sysfs_add_qgroups(fs_info);
+ if (ret < 0)
+ goto out;
/* default this to quota off, in case no status key is found */
fs_info->qgroup_flags = 0;
@@ -500,16 +513,12 @@ int btrfs_read_qgroup_config(struct btrfs_fs_info *fs_info)
ulist_free(fs_info->qgroup_ulist);
fs_info->qgroup_ulist = NULL;
fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
+ btrfs_sysfs_del_qgroups(fs_info);
}
return ret < 0 ? ret : 0;
}
-static u64 btrfs_qgroup_subvolid(u64 qgroupid)
-{
- return (qgroupid & ((1ULL << BTRFS_QGROUP_LEVEL_SHIFT) - 1));
-}
-
/*
* Called in close_ctree() when quota is still enabled. This verifies we don't
* leak some reserved space.
@@ -562,7 +571,7 @@ void btrfs_free_qgroup_config(struct btrfs_fs_info *fs_info)
while ((n = rb_first(&fs_info->qgroup_tree))) {
qgroup = rb_entry(n, struct btrfs_qgroup, node);
rb_erase(n, &fs_info->qgroup_tree);
- __del_qgroup_rb(qgroup);
+ __del_qgroup_rb(fs_info, qgroup);
}
/*
* We call btrfs_free_qgroup_config() when unmounting
@@ -571,6 +580,7 @@ void btrfs_free_qgroup_config(struct btrfs_fs_info *fs_info)
*/
ulist_free(fs_info->qgroup_ulist);
fs_info->qgroup_ulist = NULL;
+ btrfs_sysfs_del_qgroups(fs_info);
}
static int add_qgroup_relation_item(struct btrfs_trans_handle *trans, u64 src,
@@ -943,6 +953,9 @@ int btrfs_quota_enable(struct btrfs_fs_info *fs_info)
goto out;
}
+ ret = btrfs_sysfs_add_qgroups(fs_info);
+ if (ret < 0)
+ goto out;
/*
* 1 for quota root item
* 1 for BTRFS_QGROUP_STATUS item
@@ -1089,6 +1102,7 @@ int btrfs_quota_enable(struct btrfs_fs_info *fs_info)
fs_info->qgroup_ulist = NULL;
if (trans)
btrfs_end_transaction(trans);
+ btrfs_sysfs_del_qgroups(fs_info);
}
mutex_unlock(&fs_info->qgroup_ioctl_lock);
return ret;
diff --git a/fs/btrfs/qgroup.h b/fs/btrfs/qgroup.h
index 3be5198a3719..728ffea7de48 100644
--- a/fs/btrfs/qgroup.h
+++ b/fs/btrfs/qgroup.h
@@ -8,6 +8,7 @@
#include <linux/spinlock.h>
#include <linux/rbtree.h>
+#include <linux/kobject.h>
#include "ulist.h"
#include "delayed-ref.h"
@@ -223,8 +224,19 @@ struct btrfs_qgroup {
*/
u64 old_refcnt;
u64 new_refcnt;
+
+ /*
+ * Sysfs kobjectid
+ */
+ struct kobject kobj;
+ struct completion kobj_unregister;
};
+static inline u64 btrfs_qgroup_subvolid(u64 qgroupid)
+{
+ return (qgroupid & ((1ULL << BTRFS_QGROUP_LEVEL_SHIFT) - 1));
+}
+
/*
* For qgroup event trace points only
*/
diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c
index a39bff64ff24..8468c0a22695 100644
--- a/fs/btrfs/sysfs.c
+++ b/fs/btrfs/sysfs.c
@@ -19,6 +19,7 @@
#include "volumes.h"
#include "space-info.h"
#include "block-group.h"
+#include "qgroup.h"
struct btrfs_feature_attr {
struct kobj_attribute kobj_attr;
@@ -1455,6 +1456,154 @@ int btrfs_sysfs_add_mounted(struct btrfs_fs_info *fs_info)
return error;
}
+#define QGROUP_ATTR(_member) \
+static ssize_t btrfs_qgroup_show_##_member(struct kobject *qgroup_kobj, \
+ struct kobj_attribute *a, char *buf) \
+{ \
+ struct kobject *fsid_kobj = qgroup_kobj->parent->parent; \
+ struct btrfs_fs_info *fs_info = to_fs_info(fsid_kobj); \
+ struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \
+ struct btrfs_qgroup, kobj); \
+ u64 val; \
+ \
+ spin_lock(&fs_info->qgroup_lock); \
+ val = qgroup->_member; \
+ spin_unlock(&fs_info->qgroup_lock); \
+ return scnprintf(buf, PAGE_SIZE, "%llu\n", val); \
+} \
+BTRFS_ATTR(qgroup, _member, btrfs_qgroup_show_##_member)
+
+#define QGROUP_RSV_ATTR(_name, _type) \
+static ssize_t btrfs_qgroup_rsv_show_##_name(struct kobject *qgroup_kobj,\
+ struct kobj_attribute *a, char *buf) \
+{ \
+ struct kobject *fsid_kobj = qgroup_kobj->parent->parent; \
+ struct btrfs_fs_info *fs_info = to_fs_info(fsid_kobj); \
+ struct btrfs_qgroup *qgroup = container_of(qgroup_kobj, \
+ struct btrfs_qgroup, kobj); \
+ u64 val; \
+ \
+ spin_lock(&fs_info->qgroup_lock); \
+ val = qgroup->rsv.values[_type]; \
+ spin_unlock(&fs_info->qgroup_lock); \
+ return scnprintf(buf, PAGE_SIZE, "%llu\n", val); \
+} \
+BTRFS_ATTR(qgroup, rsv_##_name, btrfs_qgroup_rsv_show_##_name)
+
+QGROUP_ATTR(rfer);
+QGROUP_ATTR(excl);
+QGROUP_ATTR(max_rfer);
+QGROUP_ATTR(max_excl);
+QGROUP_ATTR(lim_flags);
+QGROUP_RSV_ATTR(data, BTRFS_QGROUP_RSV_DATA);
+QGROUP_RSV_ATTR(meta_pertrans, BTRFS_QGROUP_RSV_META_PERTRANS);
+QGROUP_RSV_ATTR(meta_prealloc, BTRFS_QGROUP_RSV_META_PREALLOC);
+
+static struct attribute *qgroup_attrs[] = {
+ BTRFS_ATTR_PTR(qgroup, rfer),
+ BTRFS_ATTR_PTR(qgroup, excl),
+ BTRFS_ATTR_PTR(qgroup, max_rfer),
+ BTRFS_ATTR_PTR(qgroup, max_excl),
+ BTRFS_ATTR_PTR(qgroup, lim_flags),
+ BTRFS_ATTR_PTR(qgroup, rsv_data),
+ BTRFS_ATTR_PTR(qgroup, rsv_meta_pertrans),
+ BTRFS_ATTR_PTR(qgroup, rsv_meta_prealloc),
+ NULL
+};
+ATTRIBUTE_GROUPS(qgroup);
+static void qgroup_release(struct kobject *kobj)
+{
+ struct btrfs_qgroup *qgroup = container_of(kobj, struct btrfs_qgroup,
+ kobj);
+ memset(&qgroup->kobj, 0, sizeof(*kobj));
+ complete(&qgroup->kobj_unregister);
+}
+
+static struct kobj_type qgroup_ktype = {
+ .sysfs_ops = &kobj_sysfs_ops,
+ .release = qgroup_release,
+ .default_groups = qgroup_groups,
+};
+
+/*
+ * Needed string buffer size for qgroup, including tailing \0
+ *
+ * This includes U48_MAX + 1 + U16_MAX + 1.
+ * U48_MAX in dec can be 15 digits at, and U16_MAX can be 6 digits.
+ * Rounded up to 32 to provide some buffer.
+ */
+#define QGROUP_STR_LEN 32
+int btrfs_sysfs_add_one_qgroup(struct btrfs_fs_info *fs_info,
+ struct btrfs_qgroup *qgroup)
+{
+ struct kobject *qgroups_kobj = fs_info->qgroup_kobj;
+ int ret;
+
+ init_completion(&qgroup->kobj_unregister);
+ ret = kobject_init_and_add(&qgroup->kobj, &qgroup_ktype, qgroups_kobj,
+ "%u_%llu", (u16)btrfs_qgroup_level(qgroup->qgroupid),
+ btrfs_qgroup_subvolid(qgroup->qgroupid));
+ if (ret < 0)
+ kobject_put(&qgroup->kobj);
+
+ return ret;
+}
+
+void btrfs_sysfs_del_qgroups(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_qgroup *qgroup;
+ struct btrfs_qgroup *next;
+
+ rbtree_postorder_for_each_entry_safe(qgroup, next,
+ &fs_info->qgroup_tree, node) {
+ if (qgroup->kobj.state_initialized) {
+ kobject_del(&qgroup->kobj);
+ kobject_put(&qgroup->kobj);
+ wait_for_completion(&qgroup->kobj_unregister);
+ }
+ }
+ kobject_del(fs_info->qgroup_kobj);
+ kobject_put(fs_info->qgroup_kobj);
+ fs_info->qgroup_kobj = NULL;
+}
+
+/* Called when qgroup get initialized, thus there is no need for extra lock. */
+int btrfs_sysfs_add_qgroups(struct btrfs_fs_info *fs_info)
+{
+ struct kobject *fsid_kobj = &fs_info->fs_devices->fsid_kobj;
+ struct btrfs_qgroup *qgroup;
+ struct btrfs_qgroup *next;
+ int ret = 0;
+
+ ASSERT(fsid_kobj);
+ if (fs_info->qgroup_kobj)
+ return 0;
+
+ fs_info->qgroup_kobj = kobject_create_and_add("qgroups", fsid_kobj);
+ if (!fs_info->qgroup_kobj) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ rbtree_postorder_for_each_entry_safe(qgroup, next,
+ &fs_info->qgroup_tree, node) {
+ ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
+ if (ret < 0)
+ goto out;
+ }
+
+out:
+ if (ret < 0)
+ btrfs_sysfs_del_qgroups(fs_info);
+ return ret;
+}
+
+void btrfs_sysfs_del_one_qgroup(struct btrfs_fs_info *fs_info,
+ struct btrfs_qgroup *qgroup)
+{
+ kobject_del(&qgroup->kobj);
+ kobject_put(&qgroup->kobj);
+ wait_for_completion(&qgroup->kobj_unregister);
+}
/*
* Change per-fs features in /sys/fs/btrfs/UUID/features to match current
diff --git a/fs/btrfs/sysfs.h b/fs/btrfs/sysfs.h
index 718a26c97833..1e27a9c94c84 100644
--- a/fs/btrfs/sysfs.h
+++ b/fs/btrfs/sysfs.h
@@ -36,4 +36,10 @@ int btrfs_sysfs_add_space_info_type(struct btrfs_fs_info *fs_info,
void btrfs_sysfs_remove_space_info(struct btrfs_space_info *space_info);
void btrfs_sysfs_update_devid(struct btrfs_device *device);
+int btrfs_sysfs_add_one_qgroup(struct btrfs_fs_info *fs_info,
+ struct btrfs_qgroup *qgroup);
+void btrfs_sysfs_del_qgroups(struct btrfs_fs_info *fs_info);
+int btrfs_sysfs_add_qgroups(struct btrfs_fs_info *fs_info);
+void btrfs_sysfs_del_one_qgroup(struct btrfs_fs_info *fs_info,
+ struct btrfs_qgroup *qgroup);
#endif
--
2.27.0
