Btrfs: Pass down the expected generation number when reading tree blocks
authorChris Mason <chris.mason@oracle.com>
Mon, 12 May 2008 16:59:19 +0000 (12:59 -0400)
committerChris Mason <chris.mason@oracle.com>
Thu, 25 Sep 2008 15:04:03 +0000 (11:04 -0400)
Signed-off-by: Chris Mason <chris.mason@oracle.com>
fs/btrfs/ctree.c
fs/btrfs/disk-io.c
fs/btrfs/disk-io.h
fs/btrfs/extent-tree.c
fs/btrfs/print-tree.c
fs/btrfs/tree-defrag.c

index 29e5674..289d71d 100644 (file)
@@ -302,6 +302,7 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans,
        struct extent_buffer *cur;
        struct extent_buffer *tmp;
        u64 blocknr;
+       u64 gen;
        u64 search_start = *last_ret;
        u64 last_block = 0;
        u64 other;
@@ -354,6 +355,7 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans,
 
                progress_passed = 1;
                blocknr = btrfs_node_blockptr(parent, i);
+               gen = btrfs_node_ptr_generation(parent, i);
                if (last_block == 0)
                        last_block = blocknr;
 
@@ -387,15 +389,14 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans,
                        }
                        if (!cur) {
                                cur = read_tree_block(root, blocknr,
-                                                        blocksize);
+                                                        blocksize, gen);
                        } else if (!uptodate) {
-                               btrfs_read_buffer(cur);
+                               btrfs_read_buffer(cur, gen);
                        }
                }
                if (search_start == 0)
                        search_start = last_block;
 
-               btrfs_verify_block_csum(root, cur);
                err = __btrfs_cow_block(trans, root, cur, parent, i,
                                        &tmp, search_start,
                                        min(16 * blocksize,
@@ -696,12 +697,17 @@ static int bin_search(struct extent_buffer *eb, struct btrfs_key *key,
 static struct extent_buffer *read_node_slot(struct btrfs_root *root,
                                   struct extent_buffer *parent, int slot)
 {
+       int level = btrfs_header_level(parent);
        if (slot < 0)
                return NULL;
        if (slot >= btrfs_header_nritems(parent))
                return NULL;
+
+       BUG_ON(level == 0);
+
        return read_tree_block(root, btrfs_node_blockptr(parent, slot),
-                      btrfs_level_size(root, btrfs_header_level(parent) - 1));
+                      btrfs_level_size(root, level - 1),
+                      btrfs_node_ptr_generation(parent, slot));
 }
 
 static int balance_level(struct btrfs_trans_handle *trans,
@@ -1076,7 +1082,8 @@ static void reada_for_search(struct btrfs_root *root, struct btrfs_path *path,
                if ((search >= lowest_read && search <= highest_read) ||
                    (search < lowest_read && lowest_read - search <= 32768) ||
                    (search > highest_read && search - highest_read <= 32768)) {
-                       readahead_tree_block(root, search, blocksize);
+                       readahead_tree_block(root, search, blocksize,
+                                    btrfs_node_ptr_generation(node, nr));
                        nread += blocksize;
                }
                nscan++;
@@ -1109,8 +1116,6 @@ int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root
                      ins_len, int cow)
 {
        struct extent_buffer *b;
-       u64 bytenr;
-       u64 ptr_gen;
        int slot;
        int ret;
        int level;
@@ -1174,20 +1179,12 @@ again:
                        /* this is only true while dropping a snapshot */
                        if (level == lowest_level)
                                break;
-                       bytenr = btrfs_node_blockptr(b, slot);
-                       ptr_gen = btrfs_node_ptr_generation(b, slot);
+
                        if (should_reada)
                                reada_for_search(root, p, level, slot,
                                                 key->objectid);
-                       b = read_tree_block(root, bytenr,
-                                           btrfs_level_size(root, level - 1));
-                       if (ptr_gen != btrfs_header_generation(b)) {
-                               printk("block %llu bad gen wanted %llu "
-                                      "found %llu\n",
-                               (unsigned long long)b->start,
-                               (unsigned long long)ptr_gen,
-                               (unsigned long long)btrfs_header_generation(b));
-                       }
+
+                       b = read_node_slot(root, b, slot);
                } else {
                        p->slots[level] = slot;
                        if (ins_len > 0 && btrfs_leaf_free_space(root, b) <
@@ -1650,8 +1647,7 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root
        if (slot >= btrfs_header_nritems(upper) - 1)
                return 1;
 
-       right = read_tree_block(root, btrfs_node_blockptr(upper, slot + 1),
-                               root->leafsize);
+       right = read_node_slot(root, upper, slot + 1);
        free_space = btrfs_leaf_free_space(root, right);
        if (free_space < data_size + sizeof(struct btrfs_item)) {
                free_extent_buffer(right);
@@ -1826,8 +1822,7 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root
                return 1;
        }
 
-       left = read_tree_block(root, btrfs_node_blockptr(path->nodes[1],
-                              slot - 1), root->leafsize);
+       left = read_node_slot(root, path->nodes[1], slot - 1);
        free_space = btrfs_leaf_free_space(root, left);
        if (free_space < data_size + sizeof(struct btrfs_item)) {
                free_extent_buffer(left);
@@ -2742,7 +2737,6 @@ int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root,
  */
 int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path)
 {
-       u64 bytenr;
        int slot;
        int level = 1;
        struct extent_buffer *c;
@@ -2762,12 +2756,10 @@ int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path)
                }
                slot--;
 
-               bytenr = btrfs_node_blockptr(c, slot);
                if (next)
                        free_extent_buffer(next);
 
-               next = read_tree_block(root, bytenr,
-                                      btrfs_level_size(root, level - 1));
+               next = read_node_slot(root, c, slot);
                break;
        }
        path->slots[level] = slot;
@@ -2782,8 +2774,7 @@ int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path)
                path->slots[level] = slot;
                if (!level)
                        break;
-               next = read_tree_block(root, btrfs_node_blockptr(next, slot),
-                                      btrfs_level_size(root, level - 1));
+               next = read_node_slot(root, next, slot);
        }
        return 0;
 }
@@ -2797,7 +2788,6 @@ int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)
 {
        int slot;
        int level = 1;
-       u64 bytenr;
        struct extent_buffer *c;
        struct extent_buffer *next = NULL;
 
@@ -2814,15 +2804,13 @@ int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)
                        continue;
                }
 
-               bytenr = btrfs_node_blockptr(c, slot);
                if (next)
                        free_extent_buffer(next);
 
                if (path->reada)
                        reada_for_search(root, path, level, slot, 0);
 
-               next = read_tree_block(root, bytenr,
-                                      btrfs_level_size(root, level -1));
+               next = read_node_slot(root, c, slot);
                break;
        }
        path->slots[level] = slot;
@@ -2836,8 +2824,7 @@ int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)
                        break;
                if (path->reada)
                        reada_for_search(root, path, level, 0, 0);
-               next = read_tree_block(root, btrfs_node_blockptr(next, 0),
-                                      btrfs_level_size(root, level - 1));
+               next = read_node_slot(root, next, 0);
        }
        return 0;
 }
index c308316..edee7a4 100644 (file)
@@ -207,7 +207,7 @@ static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
 
 static int btree_read_extent_buffer_pages(struct btrfs_root *root,
                                          struct extent_buffer *eb,
-                                         u64 start)
+                                         u64 start, u64 parent_transid)
 {
        struct extent_io_tree *io_tree;
        int ret;
@@ -254,7 +254,8 @@ int csum_dirty_buffer(struct btrfs_root *root, struct page *page)
                WARN_ON(1);
        }
        eb = alloc_extent_buffer(tree, start, len, page, GFP_NOFS);
-       ret = btree_read_extent_buffer_pages(root, eb, start + PAGE_CACHE_SIZE);
+       ret = btree_read_extent_buffer_pages(root, eb, start + PAGE_CACHE_SIZE,
+                                            btrfs_header_generation(eb));
        BUG_ON(ret);
        btrfs_clear_buffer_defrag(eb);
        found_start = btrfs_header_bytenr(eb);
@@ -562,7 +563,8 @@ static struct address_space_operations btree_aops = {
        .sync_page      = block_sync_page,
 };
 
-int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize)
+int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
+                        u64 parent_transid)
 {
        struct extent_buffer *buf = NULL;
        struct inode *btree_inode = root->fs_info->btree_inode;
@@ -592,12 +594,6 @@ static int close_all_devices(struct btrfs_fs_info *fs_info)
        return 0;
 }
 
-int btrfs_verify_block_csum(struct btrfs_root *root,
-                           struct extent_buffer *buf)
-{
-       return btrfs_buffer_uptodate(buf);
-}
-
 struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
                                            u64 bytenr, u32 blocksize)
 {
@@ -621,7 +617,7 @@ struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
 
 
 struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
-                                     u32 blocksize)
+                                     u32 blocksize, u64 parent_transid)
 {
        struct extent_buffer *buf = NULL;
        struct inode *btree_inode = root->fs_info->btree_inode;
@@ -634,7 +630,7 @@ struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
        if (!buf)
                return NULL;
 
-       ret = btree_read_extent_buffer_pages(root, buf, 0);
+       ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
 
        if (ret == 0) {
                buf->flags |= EXTENT_UPTODATE;
@@ -715,7 +711,7 @@ static int find_and_setup_root(struct btrfs_root *tree_root,
 
        blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
        root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
-                                    blocksize);
+                                    blocksize, 0);
        BUG_ON(!root->node);
        return 0;
 }
@@ -771,7 +767,7 @@ out:
        }
        blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
        root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
-                                    blocksize);
+                                    blocksize, 0);
        BUG_ON(!root->node);
 insert:
        root->ref_cows = 1;
@@ -1288,7 +1284,7 @@ struct btrfs_root *open_ctree(struct super_block *sb,
 
        chunk_root->node = read_tree_block(chunk_root,
                                           btrfs_super_chunk_root(disk_super),
-                                          blocksize);
+                                          blocksize, 0);
        BUG_ON(!chunk_root->node);
 
        read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
@@ -1304,7 +1300,7 @@ struct btrfs_root *open_ctree(struct super_block *sb,
 
        tree_root->node = read_tree_block(tree_root,
                                          btrfs_super_root(disk_super),
-                                         blocksize);
+                                         blocksize, 0);
        if (!tree_root->node)
                goto fail_sb_buffer;
 
@@ -1732,11 +1728,11 @@ int btrfs_clear_buffer_defrag(struct extent_buffer *buf)
                     EXTENT_DEFRAG, GFP_NOFS);
 }
 
-int btrfs_read_buffer(struct extent_buffer *buf)
+int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid)
 {
        struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
        int ret;
-       ret = btree_read_extent_buffer_pages(root, buf, 0);
+       ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
        if (ret == 0) {
                buf->flags |= EXTENT_UPTODATE;
        }
index 5d5f697..e29c895 100644 (file)
@@ -25,8 +25,9 @@ struct btrfs_device;
 struct btrfs_fs_devices;
 
 struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
-                                     u32 blocksize);
-int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize);
+                                     u32 blocksize, u64 parent_transid);
+int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
+                        u64 parent_transid);
 struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
                                                   u64 bytenr, u32 blocksize);
 int clean_tree_block(struct btrfs_trans_handle *trans,
@@ -65,7 +66,7 @@ int btrfs_buffer_defrag(struct extent_buffer *buf);
 int btrfs_buffer_defrag_done(struct extent_buffer *buf);
 int btrfs_clear_buffer_defrag(struct extent_buffer *buf);
 int btrfs_clear_buffer_defrag_done(struct extent_buffer *buf);
-int btrfs_read_buffer(struct extent_buffer *buf);
+int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid);
 u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len);
 void btrfs_csum_final(u32 crc, char *result);
 void btrfs_throttle(struct btrfs_root *root);
index df95fb6..db07dde 100644 (file)
@@ -1338,7 +1338,8 @@ static int finish_current_insert(struct btrfs_trans_handle *trans,
                                        &extent_item, sizeof(extent_item));
                clear_extent_bits(&info->extent_ins, start, end, EXTENT_LOCKED,
                                  GFP_NOFS);
-               eb = read_tree_block(extent_root, ins.objectid, ins.offset);
+               eb = read_tree_block(extent_root, ins.objectid, ins.offset,
+                                    trans->transid);
                level = btrfs_header_level(eb);
                if (level == 0) {
                        btrfs_item_key(eb, &first, 0);
@@ -2076,7 +2077,8 @@ static void noinline reada_walk_down(struct btrfs_root *root,
                        }
                }
                mutex_unlock(&root->fs_info->fs_mutex);
-               ret = readahead_tree_block(root, bytenr, blocksize);
+               ret = readahead_tree_block(root, bytenr, blocksize,
+                                          btrfs_node_ptr_generation(node, i));
                last = bytenr + blocksize;
                cond_resched();
                mutex_lock(&root->fs_info->fs_mutex);
@@ -2096,6 +2098,7 @@ static int noinline walk_down_tree(struct btrfs_trans_handle *trans,
        u64 root_owner;
        u64 root_gen;
        u64 bytenr;
+       u64 ptr_gen;
        struct extent_buffer *next;
        struct extent_buffer *cur;
        struct extent_buffer *parent;
@@ -2132,6 +2135,7 @@ static int noinline walk_down_tree(struct btrfs_trans_handle *trans,
                        break;
                }
                bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
+               ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
                blocksize = btrfs_level_size(root, *level - 1);
                ret = lookup_extent_ref(trans, root, bytenr, blocksize, &refs);
                BUG_ON(ret);
@@ -2152,7 +2156,8 @@ static int noinline walk_down_tree(struct btrfs_trans_handle *trans,
                        reada_walk_down(root, cur, path->slots[*level]);
 
                        mutex_unlock(&root->fs_info->fs_mutex);
-                       next = read_tree_block(root, bytenr, blocksize);
+                       next = read_tree_block(root, bytenr, blocksize,
+                                              ptr_gen);
                        mutex_lock(&root->fs_info->fs_mutex);
 
                        /* we've dropped the lock, double check */
@@ -2173,8 +2178,6 @@ static int noinline walk_down_tree(struct btrfs_trans_handle *trans,
                                BUG_ON(ret);
                                continue;
                        }
-               } else if (next) {
-                       btrfs_verify_block_csum(root, next);
                }
                WARN_ON(*level <= 0);
                if (path->nodes[*level-1])
@@ -2609,7 +2612,7 @@ static int noinline relocate_one_reference(struct btrfs_root *extent_root,
                int i;
 
                eb = read_tree_block(found_root, extent_key->objectid,
-                                    extent_key->offset);
+                                    extent_key->offset, 0);
                level = btrfs_header_level(eb);
 
                if (level == 0)
index e99f324..14d8637 100644 (file)
@@ -186,7 +186,8 @@ void btrfs_print_tree(struct btrfs_root *root, struct extent_buffer *c)
        for (i = 0; i < nr; i++) {
                struct extent_buffer *next = read_tree_block(root,
                                        btrfs_node_blockptr(c, i),
-                                       btrfs_level_size(root, level - 1));
+                                       btrfs_level_size(root, level - 1),
+                                       btrfs_node_ptr_generation(c, i));
                if (btrfs_is_leaf(next) &&
                    btrfs_header_level(c) != 1)
                        BUG();
index 256af18..5085e9e 100644 (file)
@@ -28,6 +28,7 @@ static void reada_defrag(struct btrfs_root *root,
        int i;
        u32 nritems;
        u64 bytenr;
+       u64 gen;
        u32 blocksize;
        int ret;
 
@@ -35,7 +36,8 @@ static void reada_defrag(struct btrfs_root *root,
        nritems = btrfs_header_nritems(node);
        for (i = 0; i < nritems; i++) {
                bytenr = btrfs_node_blockptr(node, i);
-               ret = readahead_tree_block(root, bytenr, blocksize);
+               gen = btrfs_node_ptr_generation(node, i);
+               ret = readahead_tree_block(root, bytenr, blocksize, gen);
                if (ret)
                        break;
        }
@@ -101,10 +103,11 @@ static int defrag_walk_down(struct btrfs_trans_handle *trans,
                                path->slots[*level]++;
                                continue;
                        }
-                       btrfs_verify_block_csum(root, next);
                } else {
                        next = read_tree_block(root, bytenr,
-                                      btrfs_level_size(root, *level - 1));
+                                      btrfs_level_size(root, *level - 1),
+                                      btrfs_node_ptr_generation(cur,
+                                                        path->slots[*level]));
                }
                ret = btrfs_cow_block(trans, root, next, path->nodes[*level],
                                      path->slots[*level], &next);