return btrfs_reduce_alloc_profile(root, flags);
}
-static u64 btrfs_get_alloc_profile(struct btrfs_root *root, int data)
+u64 btrfs_get_alloc_profile(struct btrfs_root *root, int data)
{
u64 flags;
return ret;
}
+/*
+ * helper to account the unused space of all the readonly block group in the
+ * list. takes mirrors into account.
+ */
+static u64 __btrfs_get_ro_block_group_free_space(struct list_head *groups_list)
+{
+ struct btrfs_block_group_cache *block_group;
+ u64 free_bytes = 0;
+ int factor;
+
+ list_for_each_entry(block_group, groups_list, list) {
+ spin_lock(&block_group->lock);
+
+ if (!block_group->ro) {
+ spin_unlock(&block_group->lock);
+ continue;
+ }
+
+ if (block_group->flags & (BTRFS_BLOCK_GROUP_RAID1 |
+ BTRFS_BLOCK_GROUP_RAID10 |
+ BTRFS_BLOCK_GROUP_DUP))
+ factor = 2;
+ else
+ factor = 1;
+
+ free_bytes += (block_group->key.offset -
+ btrfs_block_group_used(&block_group->item)) *
+ factor;
+
+ spin_unlock(&block_group->lock);
+ }
+
+ return free_bytes;
+}
+
+/*
+ * helper to account the unused space of all the readonly block group in the
+ * space_info. takes mirrors into account.
+ */
+u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo)
+{
+ int i;
+ u64 free_bytes = 0;
+
+ spin_lock(&sinfo->lock);
+
+ for(i = 0; i < BTRFS_NR_RAID_TYPES; i++)
+ if (!list_empty(&sinfo->block_groups[i]))
+ free_bytes += __btrfs_get_ro_block_group_free_space(
+ &sinfo->block_groups[i]);
+
+ spin_unlock(&sinfo->lock);
+
+ return free_bytes;
+}
+
int btrfs_set_block_group_rw(struct btrfs_root *root,
struct btrfs_block_group_cache *cache)
{
return 0;
}
+/*
+ * The helper to calc the free space on the devices that can be used to store
+ * file data.
+ */
+static int btrfs_calc_avail_data_space(struct btrfs_root *root, u64 *free_bytes)
+{
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ struct btrfs_device_info *devices_info;
+ struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
+ struct btrfs_device *device;
+ u64 skip_space;
+ u64 type;
+ u64 avail_space;
+ u64 used_space;
+ u64 min_stripe_size;
+ int min_stripes = 1;
+ int i = 0, nr_devices;
+ int ret;
+
+ nr_devices = fs_info->fs_devices->rw_devices;
+ BUG_ON(!nr_devices);
+
+ devices_info = kmalloc(sizeof(*devices_info) * nr_devices,
+ GFP_NOFS);
+ if (!devices_info)
+ return -ENOMEM;
+
+ /* calc min stripe number for data space alloction */
+ type = btrfs_get_alloc_profile(root, 1);
+ if (type & BTRFS_BLOCK_GROUP_RAID0)
+ min_stripes = 2;
+ else if (type & BTRFS_BLOCK_GROUP_RAID1)
+ min_stripes = 2;
+ else if (type & BTRFS_BLOCK_GROUP_RAID10)
+ min_stripes = 4;
+
+ if (type & BTRFS_BLOCK_GROUP_DUP)
+ min_stripe_size = 2 * BTRFS_STRIPE_LEN;
+ else
+ min_stripe_size = BTRFS_STRIPE_LEN;
+
+ list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
+ if (!device->in_fs_metadata)
+ continue;
+
+ avail_space = device->total_bytes - device->bytes_used;
+
+ /* align with stripe_len */
+ do_div(avail_space, BTRFS_STRIPE_LEN);
+ avail_space *= BTRFS_STRIPE_LEN;
+
+ /*
+ * In order to avoid overwritting the superblock on the drive,
+ * btrfs starts at an offset of at least 1MB when doing chunk
+ * allocation.
+ */
+ skip_space = 1024 * 1024;
+
+ /* user can set the offset in fs_info->alloc_start. */
+ if (fs_info->alloc_start + BTRFS_STRIPE_LEN <=
+ device->total_bytes)
+ skip_space = max(fs_info->alloc_start, skip_space);
+
+ /*
+ * btrfs can not use the free space in [0, skip_space - 1],
+ * we must subtract it from the total. In order to implement
+ * it, we account the used space in this range first.
+ */
+ ret = btrfs_account_dev_extents_size(device, 0, skip_space - 1,
+ &used_space);
+ if (ret) {
+ kfree(devices_info);
+ return ret;
+ }
+
+ /* calc the free space in [0, skip_space - 1] */
+ skip_space -= used_space;
+
+ /*
+ * we can use the free space in [0, skip_space - 1], subtract
+ * it from the total.
+ */
+ if (avail_space && avail_space >= skip_space)
+ avail_space -= skip_space;
+ else
+ avail_space = 0;
+
+ if (avail_space < min_stripe_size)
+ continue;
+
+ devices_info[i].dev = device;
+ devices_info[i].max_avail = avail_space;
+
+ i++;
+ }
+
+ nr_devices = i;
+
+ btrfs_descending_sort_devices(devices_info, nr_devices);
+
+ i = nr_devices - 1;
+ avail_space = 0;
+ while (nr_devices >= min_stripes) {
+ if (devices_info[i].max_avail >= min_stripe_size) {
+ int j;
+ u64 alloc_size;
+
+ avail_space += devices_info[i].max_avail * min_stripes;
+ alloc_size = devices_info[i].max_avail;
+ for (j = i + 1 - min_stripes; j <= i; j++)
+ devices_info[j].max_avail -= alloc_size;
+ }
+ i--;
+ nr_devices--;
+ }
+
+ kfree(devices_info);
+ *free_bytes = avail_space;
+ return 0;
+}
+
static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf)
{
struct btrfs_root *root = btrfs_sb(dentry->d_sb);
struct list_head *head = &root->fs_info->space_info;
struct btrfs_space_info *found;
u64 total_used = 0;
- u64 total_used_data = 0;
+ u64 total_free_data = 0;
int bits = dentry->d_sb->s_blocksize_bits;
__be32 *fsid = (__be32 *)root->fs_info->fsid;
+ int ret;
+ /* holding chunk_muext to avoid allocating new chunks */
+ mutex_lock(&root->fs_info->chunk_mutex);
rcu_read_lock();
list_for_each_entry_rcu(found, head, list) {
- if (found->flags & BTRFS_BLOCK_GROUP_DATA)
- total_used_data += found->disk_used;
- else
- total_used_data += found->disk_total;
+ if (found->flags & BTRFS_BLOCK_GROUP_DATA) {
+ total_free_data += found->disk_total - found->disk_used;
+ total_free_data -=
+ btrfs_account_ro_block_groups_free_space(found);
+ }
+
total_used += found->disk_used;
}
rcu_read_unlock();
buf->f_namelen = BTRFS_NAME_LEN;
buf->f_blocks = btrfs_super_total_bytes(disk_super) >> bits;
buf->f_bfree = buf->f_blocks - (total_used >> bits);
- buf->f_bavail = buf->f_blocks - (total_used_data >> bits);
buf->f_bsize = dentry->d_sb->s_blocksize;
buf->f_type = BTRFS_SUPER_MAGIC;
+ buf->f_bavail = total_free_data;
+ ret = btrfs_calc_avail_data_space(root, &total_free_data);
+ if (ret) {
+ mutex_unlock(&root->fs_info->chunk_mutex);
+ return ret;
+ }
+ buf->f_bavail += total_free_data;
+ buf->f_bavail = buf->f_bavail >> bits;
+ mutex_unlock(&root->fs_info->chunk_mutex);
/* We treat it as constant endianness (it doesn't matter _which_)
because we want the fsid to come out the same whether mounted
return ret;
}
+/* helper to account the used device space in the range */
+int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
+ u64 end, u64 *length)
+{
+ struct btrfs_key key;
+ struct btrfs_root *root = device->dev_root;
+ struct btrfs_dev_extent *dev_extent;
+ struct btrfs_path *path;
+ u64 extent_end;
+ int ret;
+ int slot;
+ struct extent_buffer *l;
+
+ *length = 0;
+
+ if (start >= device->total_bytes)
+ return 0;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+ path->reada = 2;
+
+ key.objectid = device->devid;
+ key.offset = start;
+ key.type = BTRFS_DEV_EXTENT_KEY;
+
+ ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
+ if (ret < 0)
+ goto out;
+ if (ret > 0) {
+ ret = btrfs_previous_item(root, path, key.objectid, key.type);
+ if (ret < 0)
+ goto out;
+ }
+
+ while (1) {
+ l = path->nodes[0];
+ slot = path->slots[0];
+ if (slot >= btrfs_header_nritems(l)) {
+ ret = btrfs_next_leaf(root, path);
+ if (ret == 0)
+ continue;
+ if (ret < 0)
+ goto out;
+
+ break;
+ }
+ btrfs_item_key_to_cpu(l, &key, slot);
+
+ if (key.objectid < device->devid)
+ goto next;
+
+ if (key.objectid > device->devid)
+ break;
+
+ if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY)
+ goto next;
+
+ dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
+ extent_end = key.offset + btrfs_dev_extent_length(l,
+ dev_extent);
+ if (key.offset <= start && extent_end > end) {
+ *length = end - start + 1;
+ break;
+ } else if (key.offset <= start && extent_end > start)
+ *length += extent_end - start;
+ else if (key.offset > start && extent_end <= end)
+ *length += extent_end - key.offset;
+ else if (key.offset > start && key.offset <= end) {
+ *length += end - key.offset + 1;
+ break;
+ } else if (key.offset > end)
+ break;
+
+next:
+ path->slots[0]++;
+ }
+ ret = 0;
+out:
+ btrfs_free_path(path);
+ return ret;
+}
+
/*
* find_free_dev_extent - find free space in the specified device
* @trans: transaction handler
projects / users / hch / configfs.git / commitdiff