Btrfs: make metadata chunks smaller

[safe/jmp/linux-2.6] / fs / btrfs / volumes.c

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index d2358c0..198cff2 100644 (file)
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -260,7 +260,7 @@ loop_lock:
                num_run++;
                batch_run++;
 
-               if (bio_sync(cur))
+               if (bio_rw_flagged(cur, BIO_RW_SYNCIO))
                        num_sync_run++;
 
                if (need_resched()) {
@@ -446,8 +446,10 @@ static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig)
                        goto error;
 
                device->name = kstrdup(orig_dev->name, GFP_NOFS);
-               if (!device->name)
+               if (!device->name) {
+                       kfree(device);
                        goto error;
+               }
 
                device->devid = orig_dev->devid;
                device->work.func = pending_bios_fn;
@@ -719,10 +721,9 @@ error:
  * called very infrequently and that a given device has a small number
  * of extents
  */
-static noinline int find_free_dev_extent(struct btrfs_trans_handle *trans,
-                                        struct btrfs_device *device,
-                                        u64 num_bytes, u64 *start,
-                                        u64 *max_avail)
+int find_free_dev_extent(struct btrfs_trans_handle *trans,
+                        struct btrfs_device *device, u64 num_bytes,
+                        u64 *start, u64 *max_avail)
 {
        struct btrfs_key key;
        struct btrfs_root *root = device->dev_root;
@@ -1736,6 +1737,10 @@ static int btrfs_relocate_chunk(struct btrfs_root *root,
        extent_root = root->fs_info->extent_root;
        em_tree = &root->fs_info->mapping_tree.map_tree;
 
+       ret = btrfs_can_relocate(extent_root, chunk_offset);
+       if (ret)
+               return -ENOSPC;
+
        /* step one, relocate all the extents inside this chunk */
        ret = btrfs_relocate_block_group(extent_root, chunk_offset);
        BUG_ON(ret);
@@ -1807,12 +1812,15 @@ static int btrfs_relocate_sys_chunks(struct btrfs_root *root)
        struct btrfs_key found_key;
        u64 chunk_tree = chunk_root->root_key.objectid;
        u64 chunk_type;
+       bool retried = false;
+       int failed = 0;
        int ret;
 
        path = btrfs_alloc_path();
        if (!path)
                return -ENOMEM;
 
+again:
        key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
        key.offset = (u64)-1;
        key.type = BTRFS_CHUNK_ITEM_KEY;
@@ -1842,7 +1850,10 @@ static int btrfs_relocate_sys_chunks(struct btrfs_root *root)
                        ret = btrfs_relocate_chunk(chunk_root, chunk_tree,
                                                   found_key.objectid,
                                                   found_key.offset);
-                       BUG_ON(ret);
+                       if (ret == -ENOSPC)
+                               failed++;
+                       else if (ret)
+                               BUG();
                }
 
                if (found_key.offset == 0)
@@ -1850,6 +1861,14 @@ static int btrfs_relocate_sys_chunks(struct btrfs_root *root)
                key.offset = found_key.offset - 1;
        }
        ret = 0;
+       if (failed && !retried) {
+               failed = 0;
+               retried = true;
+               goto again;
+       } else if (failed && retried) {
+               WARN_ON(1);
+               ret = -ENOSPC;
+       }
 error:
        btrfs_free_path(path);
        return ret;
@@ -1894,6 +1913,8 @@ int btrfs_balance(struct btrfs_root *dev_root)
                        continue;
 
                ret = btrfs_shrink_device(device, old_size - size_to_free);
+               if (ret == -ENOSPC)
+                       break;
                BUG_ON(ret);
 
                trans = btrfs_start_transaction(dev_root, 1);
@@ -1938,9 +1959,8 @@ int btrfs_balance(struct btrfs_root *dev_root)
                chunk = btrfs_item_ptr(path->nodes[0],
                                       path->slots[0],
                                       struct btrfs_chunk);
-               key.offset = found_key.offset;
                /* chunk zero is special */
-               if (key.offset == 0)
+               if (found_key.offset == 0)
                        break;
 
                btrfs_release_path(chunk_root, path);
@@ -1948,7 +1968,8 @@ int btrfs_balance(struct btrfs_root *dev_root)
                                           chunk_root->root_key.objectid,
                                           found_key.objectid,
                                           found_key.offset);
-               BUG_ON(ret);
+               BUG_ON(ret && ret != -ENOSPC);
+               key.offset = found_key.offset - 1;
        }
        ret = 0;
 error:
@@ -1974,10 +1995,13 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
        u64 chunk_offset;
        int ret;
        int slot;
+       int failed = 0;
+       bool retried = false;
        struct extent_buffer *l;
        struct btrfs_key key;
        struct btrfs_super_block *super_copy = &root->fs_info->super_copy;
        u64 old_total = btrfs_super_total_bytes(super_copy);
+       u64 old_size = device->total_bytes;
        u64 diff = device->total_bytes - new_size;
 
        if (new_size >= device->total_bytes)
@@ -1987,12 +2011,6 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
        if (!path)
                return -ENOMEM;
 
-       trans = btrfs_start_transaction(root, 1);
-       if (!trans) {
-               ret = -ENOMEM;
-               goto done;
-       }
-
        path->reada = 2;
 
        lock_chunks(root);
@@ -2001,8 +2019,8 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
        if (device->writeable)
                device->fs_devices->total_rw_bytes -= diff;
        unlock_chunks(root);
-       btrfs_end_transaction(trans, root);
 
+again:
        key.objectid = device->devid;
        key.offset = (u64)-1;
        key.type = BTRFS_DEV_EXTENT_KEY;
@@ -2017,6 +2035,7 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
                        goto done;
                if (ret) {
                        ret = 0;
+                       btrfs_release_path(root, path);
                        break;
                }
 
@@ -2024,14 +2043,18 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
                slot = path->slots[0];
                btrfs_item_key_to_cpu(l, &key, path->slots[0]);
 
-               if (key.objectid != device->devid)
+               if (key.objectid != device->devid) {
+                       btrfs_release_path(root, path);
                        break;
+               }
 
                dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
                length = btrfs_dev_extent_length(l, dev_extent);
 
-               if (key.offset + length <= new_size)
+               if (key.offset + length <= new_size) {
+                       btrfs_release_path(root, path);
                        break;
+               }
 
                chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent);
                chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent);
@@ -2040,8 +2063,26 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
 
                ret = btrfs_relocate_chunk(root, chunk_tree, chunk_objectid,
                                           chunk_offset);
-               if (ret)
+               if (ret && ret != -ENOSPC)
                        goto done;
+               if (ret == -ENOSPC)
+                       failed++;
+               key.offset -= 1;
+       }
+
+       if (failed && !retried) {
+               failed = 0;
+               retried = true;
+               goto again;
+       } else if (failed && retried) {
+               ret = -ENOSPC;
+               lock_chunks(root);
+
+               device->total_bytes = old_size;
+               if (device->writeable)
+                       device->fs_devices->total_rw_bytes += diff;
+               unlock_chunks(root);
+               goto done;
        }
 
        /* Shrinking succeeded, else we would be at "done". */
@@ -2168,7 +2209,7 @@ static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
                max_chunk_size = 10 * calc_size;
                min_stripe_size = 64 * 1024 * 1024;
        } else if (type & BTRFS_BLOCK_GROUP_METADATA) {
-               max_chunk_size = 4 * calc_size;
+               max_chunk_size = 256 * 1024 * 1024;
                min_stripe_size = 32 * 1024 * 1024;
        } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
                calc_size = 8 * 1024 * 1024;
@@ -2903,7 +2944,7 @@ static noinline int schedule_bio(struct btrfs_root *root,
        bio->bi_rw |= rw;
 
        spin_lock(&device->io_lock);
-       if (bio_sync(bio))
+       if (bio_rw_flagged(bio, BIO_RW_SYNCIO))
                pending_bios = &device->pending_sync_bios;
        else
                pending_bios = &device->pending_bios;