This patch introduces a basic form of progress monitoring for balance operations, by counting the number of block groups remaining. The information is exposed to userspace by an ioctl.
Signed-off-by: Hugo Mills <h...@carfax.org.uk> --- fs/btrfs/ctree.h | 9 +++++++ fs/btrfs/disk-io.c | 2 + fs/btrfs/ioctl.c | 34 +++++++++++++++++++++++++++++ fs/btrfs/ioctl.h | 7 ++++++ fs/btrfs/volumes.c | 61 ++++++++++++++++++++++++++++++++++++++++++++++++++- 5 files changed, 111 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 7f78cc7..6c5526c 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -865,6 +865,11 @@ struct btrfs_block_group_cache { struct list_head cluster_list; }; +struct btrfs_balance_info { + u64 expected; + u64 completed; +}; + struct reloc_control; struct btrfs_device; struct btrfs_fs_devices; @@ -1078,6 +1083,10 @@ struct btrfs_fs_info { /* filesystem state */ u64 fs_state; + + /* Keep track of any rebalance operations on this FS */ + spinlock_t balance_info_lock; + struct btrfs_balance_info *balance_info; }; /* diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 100b07f..3d690de 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -1645,6 +1645,7 @@ struct btrfs_root *open_ctree(struct super_block *sb, spin_lock_init(&fs_info->ref_cache_lock); spin_lock_init(&fs_info->fs_roots_radix_lock); spin_lock_init(&fs_info->delayed_iput_lock); + spin_lock_init(&fs_info->balance_info_lock); init_completion(&fs_info->kobj_unregister); fs_info->tree_root = tree_root; @@ -1670,6 +1671,7 @@ struct btrfs_root *open_ctree(struct super_block *sb, fs_info->sb = sb; fs_info->max_inline = 8192 * 1024; fs_info->metadata_ratio = 0; + fs_info->balance_info = NULL; fs_info->thread_pool_size = min_t(unsigned long, num_online_cpus() + 2, 8); diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 5fdb2ab..a8fbb07 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -2375,6 +2375,38 @@ static noinline long btrfs_ioctl_wait_sync(struct file *file, void __user *argp) return btrfs_wait_for_commit(root, transid); } +/* + * Return the current status of any balance operation + */ +long btrfs_ioctl_balance_progress( + struct btrfs_fs_info *fs_info, + struct btrfs_ioctl_balance_progress __user *user_dest) +{ + int ret = 0; + struct btrfs_ioctl_balance_progress dest; + + spin_lock(&fs_info->balance_info_lock); + if (!fs_info->balance_info) { + ret = -EINVAL; + goto error; + } + + dest.expected = fs_info->balance_info->expected; + dest.completed = fs_info->balance_info->completed; + + spin_unlock(&fs_info->balance_info_lock); + + if (copy_to_user(user_dest, &dest, + sizeof(struct btrfs_ioctl_balance_progress))) + return -EFAULT; + + return 0; + +error: + spin_unlock(&fs_info->balance_info_lock); + return ret; +} + long btrfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { @@ -2414,6 +2446,8 @@ long btrfs_ioctl(struct file *file, unsigned int return btrfs_ioctl_rm_dev(root, argp); case BTRFS_IOC_BALANCE: return btrfs_balance(root->fs_info->dev_root); + case BTRFS_IOC_BALANCE_PROGRESS: + return btrfs_ioctl_balance_progress(root->fs_info, argp); case BTRFS_IOC_CLONE: return btrfs_ioctl_clone(file, arg, 0, 0, 0); case BTRFS_IOC_CLONE_RANGE: diff --git a/fs/btrfs/ioctl.h b/fs/btrfs/ioctl.h index 8fb3821..4c82d40 100644 --- a/fs/btrfs/ioctl.h +++ b/fs/btrfs/ioctl.h @@ -157,6 +157,11 @@ struct btrfs_ioctl_space_args { struct btrfs_ioctl_space_info spaces[0]; }; +struct btrfs_ioctl_balance_progress { + __u64 expected; + __u64 completed; +}; + #define BTRFS_IOC_SNAP_CREATE _IOW(BTRFS_IOCTL_MAGIC, 1, \ struct btrfs_ioctl_vol_args) #define BTRFS_IOC_DEFRAG _IOW(BTRFS_IOCTL_MAGIC, 2, \ @@ -203,4 +208,6 @@ struct btrfs_ioctl_space_args { struct btrfs_ioctl_vol_args_v2) #define BTRFS_IOC_SUBVOL_GETFLAGS _IOW(BTRFS_IOCTL_MAGIC, 25, __u64) #define BTRFS_IOC_SUBVOL_SETFLAGS _IOW(BTRFS_IOCTL_MAGIC, 26, __u64) +#define BTRFS_IOC_BALANCE_PROGRESS _IOR(BTRFS_IOCTL_MAGIC, 27, \ + struct btrfs_ioctl_balance_progress) #endif diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index dd13eb8..2bd4565 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -2041,6 +2041,7 @@ int btrfs_balance(struct btrfs_root *dev_root) struct btrfs_root *chunk_root = dev_root->fs_info->chunk_root; struct btrfs_trans_handle *trans; struct btrfs_key found_key; + struct btrfs_balance_info *bal_info; if (dev_root->fs_info->sb->s_flags & MS_RDONLY) return -EROFS; @@ -2051,6 +2052,20 @@ int btrfs_balance(struct btrfs_root *dev_root) mutex_lock(&dev_root->fs_info->volume_mutex); dev_root = dev_root->fs_info->dev_root; + bal_info = kmalloc( + sizeof(struct btrfs_balance_info), + GFP_NOFS); + if (!bal_info) { + ret = -ENOSPC; + goto error_no_status; + } + spin_lock(&dev_root->fs_info->balance_info_lock); + dev_root->fs_info->balance_info = bal_info; + bal_info->expected = -1; /* One less than actually counted, + because chunk 0 is special */ + bal_info->completed = 0; + spin_unlock(&dev_root->fs_info->balance_info_lock); + /* step one make some room on all the devices */ list_for_each_entry(device, devices, dev_list) { old_size = device->total_bytes; @@ -2074,10 +2089,42 @@ int btrfs_balance(struct btrfs_root *dev_root) btrfs_end_transaction(trans, dev_root); } - /* step two, relocate all the chunks */ + /* step two, count the chunks */ path = btrfs_alloc_path(); - BUG_ON(!path); + if (!path) { + ret = -ENOSPC; + goto error; + } + + key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; + key.offset = (u64)-1; + key.type = BTRFS_CHUNK_ITEM_KEY; + + ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0); + if (ret <= 0) { + printk(KERN_ERR "btrfs: Failed to find the last chunk.\n"); + BUG(); + } + + while (1) { + ret = btrfs_previous_item(chunk_root, path, 0, + BTRFS_CHUNK_ITEM_KEY); + if (ret) + break; + + spin_lock(&dev_root->fs_info->balance_info_lock); + bal_info->expected++; + spin_unlock(&dev_root->fs_info->balance_info_lock); + } + + btrfs_free_path(path); + path = btrfs_alloc_path(); + if (!path) { + ret = -ENOSPC; + goto error; + } + /* step three, relocate all the chunks */ key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; key.offset = (u64)-1; key.type = BTRFS_CHUNK_ITEM_KEY; @@ -2115,10 +2162,20 @@ int btrfs_balance(struct btrfs_root *dev_root) found_key.offset); BUG_ON(ret && ret != -ENOSPC); key.offset = found_key.offset - 1; + spin_lock(&dev_root->fs_info->balance_info_lock); + bal_info->completed++; + spin_unlock(&dev_root->fs_info->balance_info_lock); + printk(KERN_INFO "btrfs: balance: %llu/%llu block groups completed\n", + bal_info->completed, bal_info->expected); } ret = 0; error: btrfs_free_path(path); + spin_lock(&dev_root->fs_info->balance_info_lock); + kfree(dev_root->fs_info->balance_info); + dev_root->fs_info->balance_info = NULL; + spin_unlock(&dev_root->fs_info->balance_info_lock); +error_no_status: mutex_unlock(&dev_root->fs_info->volume_mutex); return ret; } -- 1.7.2.5 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html