Btrfs: Add per-root block accounting and sysfs entries
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile
index ea7a228..ee505c8 100644
--- a/fs/btrfs/Makefile
+++ b/fs/btrfs/Makefile
@@ -5,7 +5,7 @@
btrfs-y := super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \
hash.o file-item.o inode-item.o inode-map.o disk-io.o \
transaction.o bit-radix.o inode.o file.o tree-defrag.o \
- extent_map.o
+ extent_map.o sysfs.o
#btrfs-y := ctree.o disk-io.o radix-tree.o extent-tree.o print-tree.o \
# root-tree.o dir-item.o hash.o file-item.o inode-item.o \
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 947f061..ffeee54 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -22,6 +22,7 @@
#include <linux/fs.h>
#include <linux/buffer_head.h>
#include <linux/workqueue.h>
+#include <linux/completion.h>
#include "bit-radix.h"
struct btrfs_trans_handle;
@@ -313,6 +314,8 @@
struct list_head trans_list;
struct list_head dead_roots;
struct delayed_work trans_work;
+ struct kobject super_kobj;
+ struct completion kobj_unregister;
int do_barriers;
int closing;
};
@@ -328,6 +331,8 @@
struct btrfs_key root_key;
struct btrfs_fs_info *fs_info;
struct inode *inode;
+ struct kobject root_kobj;
+ struct completion kobj_unregister;
u64 objectid;
u64 last_trans;
u32 blocksize;
@@ -338,6 +343,7 @@
struct btrfs_key defrag_progress;
int defrag_running;
int defrag_level;
+ char *name;
};
/* the lower bits in the key flags defines the item type */
@@ -814,6 +820,28 @@
item->flags = cpu_to_le32(val);
}
+static inline void btrfs_set_root_blocks_used(struct btrfs_root_item *item,
+ u64 val)
+{
+ item->blocks_used = cpu_to_le64(val);
+}
+
+static inline u64 btrfs_root_blocks_used(struct btrfs_root_item *item)
+{
+ return le64_to_cpu(item->blocks_used);
+}
+
+static inline void btrfs_set_root_block_limit(struct btrfs_root_item *item,
+ u64 val)
+{
+ item->block_limit = cpu_to_le64(val);
+}
+
+static inline u64 btrfs_root_block_limit(struct btrfs_root_item *item)
+{
+ return le64_to_cpu(item->block_limit);
+}
+
static inline u64 btrfs_super_blocknr(struct btrfs_super_block *s)
{
return le64_to_cpu(s->blocknr);
@@ -1014,6 +1042,23 @@
memmove(dst, src, nr);
}
+static inline int btrfs_set_root_name(struct btrfs_root *root,
+ const char *name, int len)
+{
+ /* if we already have a name just free it */
+ if (root->name)
+ kfree(root->name);
+
+ root->name = kmalloc(len+1, GFP_KERNEL);
+ if (!root->name)
+ return -ENOMEM;
+
+ memcpy(root->name, name, len);
+ root->name[len] ='\0';
+
+ return 0;
+}
+
/* helper function to cast into the data area of the leaf. */
#define btrfs_item_ptr(leaf, slot, type) \
((type *)(btrfs_leaf_data(leaf) + \
@@ -1191,4 +1236,13 @@
/* tree-defrag.c */
int btrfs_defrag_leaves(struct btrfs_trans_handle *trans,
struct btrfs_root *root, int cache_only);
+
+/* sysfs.c */
+int btrfs_init_sysfs(void);
+void btrfs_exit_sysfs(void);
+int btrfs_sysfs_add_super(struct btrfs_fs_info *fs);
+int btrfs_sysfs_add_root(struct btrfs_root *root);
+void btrfs_sysfs_del_root(struct btrfs_root *root);
+void btrfs_sysfs_del_super(struct btrfs_fs_info *root);
+
#endif
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index b2f7987..c25ef0a 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -294,9 +294,12 @@
root->last_trans = 0;
root->highest_inode = 0;
root->last_inode_alloc = 0;
+ root->name = NULL;
memset(&root->root_key, 0, sizeof(root->root_key));
memset(&root->root_item, 0, sizeof(root->root_item));
memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
+ memset(&root->root_kobj, 0, sizeof(root->root_kobj));
+ init_completion(&root->kobj_unregister);
root->defrag_running = 0;
root->defrag_level = 0;
root->root_key.objectid = objectid;
@@ -384,7 +387,8 @@
}
struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
- struct btrfs_key *location)
+ struct btrfs_key *location,
+ const char *name, int namelen)
{
struct btrfs_root *root;
int ret;
@@ -405,6 +409,22 @@
kfree(root);
return ERR_PTR(ret);
}
+
+ ret = btrfs_set_root_name(root, name, namelen);
+ if (ret) {
+ brelse(root->node);
+ kfree(root);
+ return ERR_PTR(ret);
+ }
+
+ ret = btrfs_sysfs_add_root(root);
+ if (ret) {
+ brelse(root->node);
+ kfree(root->name);
+ kfree(root);
+ return ERR_PTR(ret);
+ }
+
return root;
}
@@ -433,6 +453,8 @@
INIT_RADIX_TREE(&fs_info->block_group_data_radix, GFP_KERNEL);
INIT_LIST_HEAD(&fs_info->trans_list);
INIT_LIST_HEAD(&fs_info->dead_roots);
+ memset(&fs_info->super_kobj, 0, sizeof(fs_info->super_kobj));
+ init_completion(&fs_info->kobj_unregister);
sb_set_blocksize(sb, 4096);
fs_info->running_transaction = NULL;
fs_info->last_trans_committed = 0;
@@ -500,8 +522,10 @@
fs_info->generation = btrfs_super_generation(disk_super) + 1;
ret = btrfs_find_dead_roots(tree_root);
- if (ret)
+ if (ret) {
+ mutex_unlock(&fs_info->fs_mutex);
goto fail_tree_root;
+ }
mutex_unlock(&fs_info->fs_mutex);
return tree_root;
@@ -553,12 +577,15 @@
{
radix_tree_delete(&fs_info->fs_roots_radix,
(unsigned long)root->root_key.objectid);
+ btrfs_sysfs_del_root(root);
if (root->inode)
iput(root->inode);
if (root->node)
brelse(root->node);
if (root->commit_root)
brelse(root->commit_root);
+ if (root->name)
+ kfree(root->name);
kfree(root);
return 0;
}
diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h
index 5261733..da6bb72 100644
--- a/fs/btrfs/disk-io.h
+++ b/fs/btrfs/disk-io.h
@@ -66,7 +66,8 @@
int btrfs_csum_data(struct btrfs_root * root, char *data, size_t len,
char *result);
struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
- struct btrfs_key *location);
+ struct btrfs_key *location,
+ const char *name, int namelen);
struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_fs_info *fs_info,
struct btrfs_key *location);
u64 bh_blocknr(struct buffer_head *bh);
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index c31e84d..ff3f7c2 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -858,16 +858,23 @@
btrfs_set_extent_refs(ei, refs);
btrfs_mark_buffer_dirty(path->nodes[0]);
if (refs == 0) {
- u64 super_blocks_used;
+ u64 super_blocks_used, root_blocks_used;
if (pin) {
ret = pin_down_block(root, blocknr, 0);
BUG_ON(ret);
}
+ /* block accounting for super block */
super_blocks_used = btrfs_super_blocks_used(&info->super_copy);
btrfs_set_super_blocks_used(&info->super_copy,
super_blocks_used - num_blocks);
+
+ /* block accounting for root item */
+ root_blocks_used = btrfs_root_blocks_used(&root->root_item);
+ btrfs_set_root_blocks_used(&root->root_item,
+ root_blocks_used - num_blocks);
+
ret = btrfs_del_item(trans, extent_root, path);
if (ret) {
return ret;
@@ -1175,7 +1182,7 @@
{
int ret;
int pending_ret;
- u64 super_blocks_used;
+ u64 super_blocks_used, root_blocks_used;
u64 search_start = 0;
struct btrfs_fs_info *info = root->fs_info;
struct btrfs_root *extent_root = info->extent_root;
@@ -1193,10 +1200,16 @@
if (ret)
return ret;
+ /* block accounting for super block */
super_blocks_used = btrfs_super_blocks_used(&info->super_copy);
btrfs_set_super_blocks_used(&info->super_copy, super_blocks_used +
num_blocks);
+ /* block accounting for root item */
+ root_blocks_used = btrfs_root_blocks_used(&root->root_item);
+ btrfs_set_root_blocks_used(&root->root_item, root_blocks_used +
+ num_blocks);
+
if (root == extent_root) {
BUG_ON(num_blocks != 1);
set_radix_bit(&root->fs_info->extent_ins_radix, ins->objectid);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index dc18108..2e3918e 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -733,7 +733,8 @@
*/
static int fixup_tree_root_location(struct btrfs_root *root,
struct btrfs_key *location,
- struct btrfs_root **sub_root)
+ struct btrfs_root **sub_root,
+ struct dentry *dentry)
{
struct btrfs_path *path;
struct btrfs_root_item *ri;
@@ -747,7 +748,9 @@
BUG_ON(!path);
mutex_lock(&root->fs_info->fs_mutex);
- *sub_root = btrfs_read_fs_root(root->fs_info, location);
+ *sub_root = btrfs_read_fs_root(root->fs_info, location,
+ dentry->d_name.name,
+ dentry->d_name.len);
if (IS_ERR(*sub_root))
return PTR_ERR(*sub_root);
@@ -812,7 +815,8 @@
return ERR_PTR(ret);
inode = NULL;
if (location.objectid) {
- ret = fixup_tree_root_location(root, &location, &sub_root);
+ ret = fixup_tree_root_location(root, &location, &sub_root,
+ dentry);
if (ret < 0)
return ERR_PTR(ret);
if (ret > 0)
@@ -1829,6 +1833,7 @@
btrfs_set_root_blocknr(&root_item, bh_blocknr(subvol));
btrfs_set_root_refs(&root_item, 1);
+ btrfs_set_root_blocks_used(&root_item, 0);
memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
root_item.drop_level = 0;
brelse(subvol);
@@ -1865,7 +1870,7 @@
if (ret)
goto fail_commit;
- new_root = btrfs_read_fs_root(root->fs_info, &key);
+ new_root = btrfs_read_fs_root(root->fs_info, &key, name, namelen);
BUG_ON(!new_root);
trans = btrfs_start_transaction(new_root, 1);
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 7da9553..a68101a 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -45,12 +45,14 @@
static void btrfs_put_super (struct super_block * sb)
{
struct btrfs_root *root = btrfs_sb(sb);
+ struct btrfs_fs_info *fs = root->fs_info;
int ret;
ret = close_ctree(root);
if (ret) {
printk("close ctree returns %d\n", ret);
}
+ btrfs_sysfs_del_super(fs);
sb->s_fs_info = NULL;
}
@@ -101,6 +103,12 @@
err = -ENOMEM;
goto fail_close;
}
+
+ /* this does the super kobj at the same time */
+ err = btrfs_sysfs_add_super(tree_root->fs_info);
+ if (err)
+ goto fail_close;
+
sb->s_root = root_dentry;
btrfs_transaction_queue_work(tree_root, HZ * 30);
return 0;
@@ -182,6 +190,11 @@
static int __init init_btrfs_fs(void)
{
int err;
+
+ err = btrfs_init_sysfs();
+ if (err)
+ return err;
+
btrfs_init_transaction_sys();
err = btrfs_init_cachep();
if (err)
@@ -196,6 +209,7 @@
btrfs_destroy_cachep();
extent_map_exit();
unregister_filesystem(&btrfs_fs_type);
+ btrfs_exit_sysfs();
}
module_init(init_btrfs_fs)
diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c
index db8917e..2058783 100644
--- a/fs/btrfs/sysfs.c
+++ b/fs/btrfs/sysfs.c
@@ -16,6 +16,242 @@
* Boston, MA 021110-1307, USA.
*/
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/completion.h>
+#include <linux/buffer_head.h>
+#include <linux/module.h>
+#include <linux/kobject.h>
+
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
+
+static ssize_t root_blocks_used_show(struct btrfs_root *root, char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "%llu\n",
+ (unsigned long long)btrfs_root_blocks_used(&root->root_item));
+}
+
+static ssize_t root_block_limit_show(struct btrfs_root *root, char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "%llu\n",
+ (unsigned long long)btrfs_root_block_limit(&root->root_item));
+}
+
+static ssize_t super_blocks_used_show(struct btrfs_fs_info *fs, char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "%llu\n",
+ (unsigned long long)btrfs_super_blocks_used(fs->disk_super));
+}
+
+static ssize_t super_total_blocks_show(struct btrfs_fs_info *fs, char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "%llu\n",
+ (unsigned long long)btrfs_super_total_blocks(fs->disk_super));
+}
+
+static ssize_t super_blocksize_show(struct btrfs_fs_info *fs, char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "%llu\n",
+ (unsigned long long)btrfs_super_blocksize(fs->disk_super));
+}
+
+/* this is for root attrs (subvols/snapshots) */
+struct btrfs_root_attr {
+ struct attribute attr;
+ ssize_t (*show)(struct btrfs_root *, char *);
+ ssize_t (*store)(struct btrfs_root *, const char *, size_t);
+};
+
+#define ROOT_ATTR(name, mode, show, store) \
+static struct btrfs_root_attr btrfs_root_attr_##name = __ATTR(name, mode, show, store)
+
+ROOT_ATTR(blocks_used, 0444, root_blocks_used_show, NULL);
+ROOT_ATTR(block_limit, 0644, root_block_limit_show, NULL);
+
+static struct attribute *btrfs_root_attrs[] = {
+ &btrfs_root_attr_blocks_used.attr,
+ &btrfs_root_attr_block_limit.attr,
+ NULL,
+};
+
+/* this is for super attrs (actual full fs) */
+struct btrfs_super_attr {
+ struct attribute attr;
+ ssize_t (*show)(struct btrfs_fs_info *, char *);
+ ssize_t (*store)(struct btrfs_fs_info *, const char *, size_t);
+};
+
+#define SUPER_ATTR(name, mode, show, store) \
+static struct btrfs_super_attr btrfs_super_attr_##name = __ATTR(name, mode, show, store)
+
+SUPER_ATTR(blocks_used, 0444, super_blocks_used_show, NULL);
+SUPER_ATTR(total_blocks, 0444, super_total_blocks_show, NULL);
+SUPER_ATTR(blocksize, 0444, super_blocksize_show, NULL);
+
+static struct attribute *btrfs_super_attrs[] = {
+ &btrfs_super_attr_blocks_used.attr,
+ &btrfs_super_attr_total_blocks.attr,
+ &btrfs_super_attr_blocksize.attr,
+ NULL,
+};
+
+static ssize_t btrfs_super_attr_show(struct kobject *kobj,
+ struct attribute *attr, char *buf)
+{
+ struct btrfs_fs_info *fs = container_of(kobj, struct btrfs_fs_info,
+ super_kobj);
+ struct btrfs_super_attr *a = container_of(attr,
+ struct btrfs_super_attr,
+ attr);
+
+ return a->show ? a->show(fs, buf) : 0;
+}
+
+static ssize_t btrfs_super_attr_store(struct kobject *kobj,
+ struct attribute *attr,
+ const char *buf, size_t len)
+{
+ struct btrfs_fs_info *fs = container_of(kobj, struct btrfs_fs_info,
+ super_kobj);
+ struct btrfs_super_attr *a = container_of(attr,
+ struct btrfs_super_attr,
+ attr);
+
+ return a->store ? a->store(fs, buf, len) : 0;
+}
+
+static ssize_t btrfs_root_attr_show(struct kobject *kobj,
+ struct attribute *attr, char *buf)
+{
+ struct btrfs_root *root = container_of(kobj, struct btrfs_root,
+ root_kobj);
+ struct btrfs_root_attr *a = container_of(attr,
+ struct btrfs_root_attr,
+ attr);
+
+ return a->show ? a->show(root, buf) : 0;
+}
+
+static ssize_t btrfs_root_attr_store(struct kobject *kobj,
+ struct attribute *attr,
+ const char *buf, size_t len)
+{
+ struct btrfs_root *root = container_of(kobj, struct btrfs_root,
+ root_kobj);
+ struct btrfs_root_attr *a = container_of(attr,
+ struct btrfs_root_attr,
+ attr);
+ return a->store ? a->store(root, buf, len) : 0;
+}
+
+static void btrfs_super_release(struct kobject *kobj)
+{
+ struct btrfs_fs_info *fs = container_of(kobj, struct btrfs_fs_info,
+ super_kobj);
+ complete(&fs->kobj_unregister);
+}
+
+static void btrfs_root_release(struct kobject *kobj)
+{
+ struct btrfs_root *root = container_of(kobj, struct btrfs_root,
+ root_kobj);
+ complete(&root->kobj_unregister);
+}
+
+static struct sysfs_ops btrfs_super_attr_ops = {
+ .show = btrfs_super_attr_show,
+ .store = btrfs_super_attr_store,
+};
+
+static struct sysfs_ops btrfs_root_attr_ops = {
+ .show = btrfs_root_attr_show,
+ .store = btrfs_root_attr_store,
+};
+
+static struct kobj_type btrfs_root_ktype = {
+ .default_attrs = btrfs_root_attrs,
+ .sysfs_ops = &btrfs_root_attr_ops,
+ .release = btrfs_root_release,
+};
+
+static struct kobj_type btrfs_super_ktype = {
+ .default_attrs = btrfs_super_attrs,
+ .sysfs_ops = &btrfs_super_attr_ops,
+ .release = btrfs_super_release,
+};
+
+static struct kset btrfs_kset = {
+ .kobj = {.name = "btrfs"},
+};
+
+int btrfs_sysfs_add_super(struct btrfs_fs_info *fs)
+{
+ int error;
+
+ fs->super_kobj.kset = &btrfs_kset;
+ fs->super_kobj.ktype = &btrfs_super_ktype;
+
+ error = kobject_set_name(&fs->super_kobj, "%s",
+ fs->sb->s_id);
+ if (error)
+ goto fail;
+
+ error = kobject_register(&fs->super_kobj);
+ if (error)
+ goto fail;
+
+ return 0;
+
+fail:
+ printk(KERN_ERR "btrfs: sysfs creation for super failed\n");
+ return error;
+}
+
+int btrfs_sysfs_add_root(struct btrfs_root *root)
+{
+ int error;
+
+ root->root_kobj.ktype = &btrfs_root_ktype;
+ root->root_kobj.parent = &root->fs_info->super_kobj;
+
+ error = kobject_set_name(&root->root_kobj, "%s", root->name);
+ if (error) {
+ goto fail;
+ }
+
+ error = kobject_register(&root->root_kobj);
+ if (error)
+ goto fail;
+
+ return 0;
+
+fail:
+ printk(KERN_ERR "btrfs: sysfs creation for root failed\n");
+ return error;
+}
+
+void btrfs_sysfs_del_root(struct btrfs_root *root)
+{
+ kobject_unregister(&root->root_kobj);
+ wait_for_completion(&root->kobj_unregister);
+}
+
+void btrfs_sysfs_del_super(struct btrfs_fs_info *fs)
+{
+ kobject_unregister(&fs->super_kobj);
+ wait_for_completion(&fs->kobj_unregister);
+}
+
+int btrfs_init_sysfs()
+{
+ kobj_set_kset_s(&btrfs_kset, fs_subsys);
+ return kset_register(&btrfs_kset);
+}
+
+void btrfs_exit_sysfs()
+{
+ kset_unregister(&btrfs_kset);
+}
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 18abea8..2b15daa 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -236,6 +236,7 @@
struct dirty_root {
struct list_head list;
struct btrfs_root *root;
+ struct btrfs_root *latest_root;
};
int btrfs_add_dead_root(struct btrfs_root *root, struct list_head *dead_list)
@@ -278,6 +279,15 @@
btrfs_root_blocknr(&root->root_item));
brelse(root->commit_root);
root->commit_root = NULL;
+
+ /* make sure to update the root on disk
+ * so we get any updates to the block used
+ * counts
+ */
+ err = btrfs_update_root(trans,
+ root->fs_info->tree_root,
+ &root->root_key,
+ &root->root_item);
continue;
}
dirty = kmalloc(sizeof(*dirty), GFP_NOFS);
@@ -291,6 +301,7 @@
memcpy(dirty->root, root, sizeof(*root));
dirty->root->node = root->commit_root;
+ dirty->latest_root = root;
root->commit_root = NULL;
root->root_key.offset = root->fs_info->generation;
@@ -384,20 +395,29 @@
{
struct dirty_root *dirty;
struct btrfs_trans_handle *trans;
+ u64 num_blocks;
+ u64 blocks_used;
int ret = 0;
int err;
while(!list_empty(list)) {
+ struct btrfs_root *root;
+
mutex_lock(&tree_root->fs_info->fs_mutex);
dirty = list_entry(list->next, struct dirty_root, list);
list_del_init(&dirty->list);
+ num_blocks = btrfs_root_blocks_used(&dirty->root->root_item);
+ root = dirty->latest_root;
+
while(1) {
trans = btrfs_start_transaction(tree_root, 1);
+
ret = btrfs_drop_snapshot(trans, dirty->root);
if (ret != -EAGAIN) {
break;
}
+
err = btrfs_update_root(trans,
tree_root,
&dirty->root->root_key,
@@ -414,9 +434,19 @@
mutex_lock(&tree_root->fs_info->fs_mutex);
}
BUG_ON(ret);
+
+ num_blocks -= btrfs_root_blocks_used(&dirty->root->root_item);
+ blocks_used = btrfs_root_blocks_used(&root->root_item);
+ if (num_blocks) {
+ record_root_in_trans(root);
+ btrfs_set_root_blocks_used(&root->root_item,
+ blocks_used - num_blocks);
+ }
ret = btrfs_del_root(trans, tree_root, &dirty->root->root_key);
- if (ret)
+ if (ret) {
+ BUG();
break;
+ }
ret = btrfs_end_transaction(trans, tree_root);
BUG_ON(ret);
@@ -534,10 +564,12 @@
wake_up(&cur_trans->commit_wait);
put_transaction(cur_trans);
put_transaction(cur_trans);
+
if (root->fs_info->closing)
list_splice_init(&root->fs_info->dead_roots, &dirty_fs_roots);
else
list_splice_init(&dirty_fs_roots, &root->fs_info->dead_roots);
+
mutex_unlock(&root->fs_info->trans_mutex);
kmem_cache_free(btrfs_trans_handle_cachep, trans);