-#include <stdio.h>
-#include <stdlib.h>
-#include "kerncompat.h"
-#include "radix-tree.h"
+/*
+ * Copyright (C) 2007 Oracle. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
#include "ctree.h"
#include "disk-io.h"
+#include "transaction.h"
+#include "print-tree.h"
+#include "repair.h"
+#include "internal.h"
+#include "sizes.h"
+
+static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root
+ *root, struct btrfs_path *path, int level);
+static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root
+ *root, struct btrfs_key *ins_key,
+ struct btrfs_path *path, int data_size, int extend);
+static int push_node_left(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, struct extent_buffer *dst,
+ struct extent_buffer *src, int empty);
+static int balance_node_right(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct extent_buffer *dst_buf,
+ struct extent_buffer *src_buf);
+
+inline void btrfs_init_path(struct btrfs_path *p)
+{
+ memset(p, 0, sizeof(*p));
+}
-static int refill_alloc_extent(struct ctree_root *root);
+struct btrfs_path *btrfs_alloc_path(void)
+{
+ struct btrfs_path *path;
+ path = kzalloc(sizeof(struct btrfs_path), GFP_NOFS);
+ return path;
+}
-static inline void init_path(struct ctree_path *p)
+void btrfs_free_path(struct btrfs_path *p)
{
- memset(p, 0, sizeof(*p));
+ if (!p)
+ return;
+ btrfs_release_path(p);
+ kfree(p);
}
-static void release_path(struct ctree_root *root, struct ctree_path *p)
+void btrfs_release_path(struct btrfs_path *p)
{
int i;
- for (i = 0; i < MAX_LEVEL; i++) {
+ for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
if (!p->nodes[i])
- break;
- tree_block_release(root, p->nodes[i]);
+ continue;
+ free_extent_buffer(p->nodes[i]);
}
+ memset(p, 0, sizeof(*p));
}
-/*
- * The leaf data grows from end-to-front in the node.
- * this returns the address of the start of the last item,
- * which is the stop of the leaf data stack
- */
-static inline unsigned int leaf_data_end(struct leaf *leaf)
+void add_root_to_dirty_list(struct btrfs_root *root)
{
- unsigned int nr = leaf->header.nritems;
- if (nr == 0)
- return sizeof(leaf->data);
- return leaf->items[nr-1].offset;
+ if (root->track_dirty && list_empty(&root->dirty_list)) {
+ list_add(&root->dirty_list,
+ &root->fs_info->dirty_cowonly_roots);
+ }
}
-/*
- * The space between the end of the leaf items and
- * the start of the leaf data. IOW, how much room
- * the leaf has left for both items and data
- */
-static inline int leaf_free_space(struct leaf *leaf)
+int btrfs_copy_root(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct extent_buffer *buf,
+ struct extent_buffer **cow_ret, u64 new_root_objectid)
{
- int data_end = leaf_data_end(leaf);
- int nritems = leaf->header.nritems;
- char *items_end = (char *)(leaf->items + nritems + 1);
- return (char *)(leaf->data + data_end) - (char *)items_end;
+ struct extent_buffer *cow;
+ int ret = 0;
+ int level;
+ struct btrfs_root *new_root;
+ struct btrfs_disk_key disk_key;
+
+ new_root = kmalloc(sizeof(*new_root), GFP_NOFS);
+ if (!new_root)
+ return -ENOMEM;
+
+ memcpy(new_root, root, sizeof(*new_root));
+ new_root->root_key.objectid = new_root_objectid;
+
+ WARN_ON(root->ref_cows && trans->transid !=
+ root->fs_info->running_transaction->transid);
+ WARN_ON(root->ref_cows && trans->transid != root->last_trans);
+
+ level = btrfs_header_level(buf);
+ if (level == 0)
+ btrfs_item_key(buf, &disk_key, 0);
+ else
+ btrfs_node_key(buf, &disk_key, 0);
+ cow = btrfs_alloc_free_block(trans, new_root, buf->len,
+ new_root_objectid, &disk_key,
+ level, buf->start, 0);
+ if (IS_ERR(cow)) {
+ kfree(new_root);
+ return PTR_ERR(cow);
+ }
+
+ copy_extent_buffer(cow, buf, 0, 0, cow->len);
+ btrfs_set_header_bytenr(cow, cow->start);
+ btrfs_set_header_generation(cow, trans->transid);
+ btrfs_set_header_backref_rev(cow, BTRFS_MIXED_BACKREF_REV);
+ btrfs_clear_header_flag(cow, BTRFS_HEADER_FLAG_WRITTEN |
+ BTRFS_HEADER_FLAG_RELOC);
+ if (new_root_objectid == BTRFS_TREE_RELOC_OBJECTID)
+ btrfs_set_header_flag(cow, BTRFS_HEADER_FLAG_RELOC);
+ else
+ btrfs_set_header_owner(cow, new_root_objectid);
+
+ write_extent_buffer(cow, root->fs_info->fsid,
+ btrfs_header_fsid(), BTRFS_FSID_SIZE);
+
+ WARN_ON(btrfs_header_generation(buf) > trans->transid);
+ ret = btrfs_inc_ref(trans, new_root, cow, 0);
+ kfree(new_root);
+
+ if (ret)
+ return ret;
+
+ btrfs_mark_buffer_dirty(cow);
+ *cow_ret = cow;
+ return 0;
}
/*
- * compare two keys in a memcmp fashion
+ * check if the tree block can be shared by multiple trees
*/
-int comp_keys(struct key *k1, struct key *k2)
+static int btrfs_block_can_be_shared(struct btrfs_root *root,
+ struct extent_buffer *buf)
+{
+ /*
+ * Tree blocks not in reference counted trees and tree roots
+ * are never shared. If a block was allocated after the last
+ * snapshot and the block was not allocated by tree relocation,
+ * we know the block is not shared.
+ */
+ if (root->ref_cows &&
+ buf != root->node && buf != root->commit_root &&
+ (btrfs_header_generation(buf) <=
+ btrfs_root_last_snapshot(&root->root_item) ||
+ btrfs_header_flag(buf, BTRFS_HEADER_FLAG_RELOC)))
+ return 1;
+#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
+ if (root->ref_cows &&
+ btrfs_header_backref_rev(buf) < BTRFS_MIXED_BACKREF_REV)
+ return 1;
+#endif
+ return 0;
+}
+
+static noinline int update_ref_for_cow(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct extent_buffer *buf,
+ struct extent_buffer *cow)
+{
+ u64 refs;
+ u64 owner;
+ u64 flags;
+ u64 new_flags = 0;
+ int ret;
+
+ /*
+ * Backrefs update rules:
+ *
+ * Always use full backrefs for extent pointers in tree block
+ * allocated by tree relocation.
+ *
+ * If a shared tree block is no longer referenced by its owner
+ * tree (btrfs_header_owner(buf) == root->root_key.objectid),
+ * use full backrefs for extent pointers in tree block.
+ *
+ * If a tree block is been relocating
+ * (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID),
+ * use full backrefs for extent pointers in tree block.
+ * The reason for this is some operations (such as drop tree)
+ * are only allowed for blocks use full backrefs.
+ */
+
+ if (btrfs_block_can_be_shared(root, buf)) {
+ ret = btrfs_lookup_extent_info(trans, root, buf->start,
+ btrfs_header_level(buf), 1,
+ &refs, &flags);
+ BUG_ON(ret);
+ BUG_ON(refs == 0);
+ } else {
+ refs = 1;
+ if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID ||
+ btrfs_header_backref_rev(buf) < BTRFS_MIXED_BACKREF_REV)
+ flags = BTRFS_BLOCK_FLAG_FULL_BACKREF;
+ else
+ flags = 0;
+ }
+
+ owner = btrfs_header_owner(buf);
+ BUG_ON(!(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF) &&
+ owner == BTRFS_TREE_RELOC_OBJECTID);
+
+ if (refs > 1) {
+ if ((owner == root->root_key.objectid ||
+ root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) &&
+ !(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)) {
+ ret = btrfs_inc_ref(trans, root, buf, 1);
+ BUG_ON(ret);
+
+ if (root->root_key.objectid ==
+ BTRFS_TREE_RELOC_OBJECTID) {
+ ret = btrfs_dec_ref(trans, root, buf, 0);
+ BUG_ON(ret);
+ ret = btrfs_inc_ref(trans, root, cow, 1);
+ BUG_ON(ret);
+ }
+ new_flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
+ } else {
+
+ if (root->root_key.objectid ==
+ BTRFS_TREE_RELOC_OBJECTID)
+ ret = btrfs_inc_ref(trans, root, cow, 1);
+ else
+ ret = btrfs_inc_ref(trans, root, cow, 0);
+ BUG_ON(ret);
+ }
+ if (new_flags != 0) {
+ ret = btrfs_set_block_flags(trans, root, buf->start,
+ btrfs_header_level(buf),
+ new_flags);
+ BUG_ON(ret);
+ }
+ } else {
+ if (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
+ if (root->root_key.objectid ==
+ BTRFS_TREE_RELOC_OBJECTID)
+ ret = btrfs_inc_ref(trans, root, cow, 1);
+ else
+ ret = btrfs_inc_ref(trans, root, cow, 0);
+ BUG_ON(ret);
+ ret = btrfs_dec_ref(trans, root, buf, 1);
+ BUG_ON(ret);
+ }
+ clean_tree_block(trans, root, buf);
+ }
+ return 0;
+}
+
+int __btrfs_cow_block(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct extent_buffer *buf,
+ struct extent_buffer *parent, int parent_slot,
+ struct extent_buffer **cow_ret,
+ u64 search_start, u64 empty_size)
+{
+ struct extent_buffer *cow;
+ struct btrfs_disk_key disk_key;
+ int level;
+
+ WARN_ON(root->ref_cows && trans->transid !=
+ root->fs_info->running_transaction->transid);
+ WARN_ON(root->ref_cows && trans->transid != root->last_trans);
+
+ level = btrfs_header_level(buf);
+
+ if (level == 0)
+ btrfs_item_key(buf, &disk_key, 0);
+ else
+ btrfs_node_key(buf, &disk_key, 0);
+
+ cow = btrfs_alloc_free_block(trans, root, buf->len,
+ root->root_key.objectid, &disk_key,
+ level, search_start, empty_size);
+ if (IS_ERR(cow))
+ return PTR_ERR(cow);
+
+ copy_extent_buffer(cow, buf, 0, 0, cow->len);
+ btrfs_set_header_bytenr(cow, cow->start);
+ btrfs_set_header_generation(cow, trans->transid);
+ btrfs_set_header_backref_rev(cow, BTRFS_MIXED_BACKREF_REV);
+ btrfs_clear_header_flag(cow, BTRFS_HEADER_FLAG_WRITTEN |
+ BTRFS_HEADER_FLAG_RELOC);
+ if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID)
+ btrfs_set_header_flag(cow, BTRFS_HEADER_FLAG_RELOC);
+ else
+ btrfs_set_header_owner(cow, root->root_key.objectid);
+
+ write_extent_buffer(cow, root->fs_info->fsid,
+ btrfs_header_fsid(), BTRFS_FSID_SIZE);
+
+ WARN_ON(!(buf->flags & EXTENT_BAD_TRANSID) &&
+ btrfs_header_generation(buf) > trans->transid);
+
+ update_ref_for_cow(trans, root, buf, cow);
+
+ if (buf == root->node) {
+ root->node = cow;
+ extent_buffer_get(cow);
+
+ btrfs_free_extent(trans, root, buf->start, buf->len,
+ 0, root->root_key.objectid, level, 0);
+ free_extent_buffer(buf);
+ add_root_to_dirty_list(root);
+ } else {
+ btrfs_set_node_blockptr(parent, parent_slot,
+ cow->start);
+ WARN_ON(trans->transid == 0);
+ btrfs_set_node_ptr_generation(parent, parent_slot,
+ trans->transid);
+ btrfs_mark_buffer_dirty(parent);
+ WARN_ON(btrfs_header_generation(parent) != trans->transid);
+
+ btrfs_free_extent(trans, root, buf->start, buf->len,
+ 0, root->root_key.objectid, level, 1);
+ }
+ if (!list_empty(&buf->recow)) {
+ list_del_init(&buf->recow);
+ free_extent_buffer(buf);
+ }
+ free_extent_buffer(buf);
+ btrfs_mark_buffer_dirty(cow);
+ *cow_ret = cow;
+ return 0;
+}
+
+static inline int should_cow_block(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct extent_buffer *buf)
+{
+ if (btrfs_header_generation(buf) == trans->transid &&
+ !btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN) &&
+ !(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID &&
+ btrfs_header_flag(buf, BTRFS_HEADER_FLAG_RELOC)))
+ return 0;
+ return 1;
+}
+
+int btrfs_cow_block(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, struct extent_buffer *buf,
+ struct extent_buffer *parent, int parent_slot,
+ struct extent_buffer **cow_ret)
+{
+ u64 search_start;
+ int ret;
+ /*
+ if (trans->transaction != root->fs_info->running_transaction) {
+ printk(KERN_CRIT "trans %Lu running %Lu\n", trans->transid,
+ root->fs_info->running_transaction->transid);
+ WARN_ON(1);
+ }
+ */
+ if (trans->transid != root->fs_info->generation) {
+ printk(KERN_CRIT "trans %llu running %llu\n",
+ (unsigned long long)trans->transid,
+ (unsigned long long)root->fs_info->generation);
+ WARN_ON(1);
+ }
+ if (!should_cow_block(trans, root, buf)) {
+ *cow_ret = buf;
+ return 0;
+ }
+
+ search_start = buf->start & ~((u64)SZ_1G - 1);
+ ret = __btrfs_cow_block(trans, root, buf, parent,
+ parent_slot, cow_ret, search_start, 0);
+ return ret;
+}
+
+int btrfs_comp_cpu_keys(struct btrfs_key *k1, struct btrfs_key *k2)
{
if (k1->objectid > k2->objectid)
return 1;
if (k1->objectid < k2->objectid)
return -1;
- if (k1->flags > k2->flags)
+ if (k1->type > k2->type)
return 1;
- if (k1->flags < k2->flags)
+ if (k1->type < k2->type)
return -1;
if (k1->offset > k2->offset)
return 1;
}
/*
- * search for key in the array p. items p are item_size apart
- * and there are 'max' items in p
+ * compare two keys in a memcmp fashion
+ */
+static int btrfs_comp_keys(struct btrfs_disk_key *disk, struct btrfs_key *k2)
+{
+ struct btrfs_key k1;
+
+ btrfs_disk_key_to_cpu(&k1, disk);
+ return btrfs_comp_cpu_keys(&k1, k2);
+}
+
+/*
+ * The leaf data grows from end-to-front in the node.
+ * this returns the address of the start of the last item,
+ * which is the stop of the leaf data stack
+ */
+static inline unsigned int leaf_data_end(const struct btrfs_fs_info *fs_info,
+ const struct extent_buffer *leaf)
+{
+ u32 nr = btrfs_header_nritems(leaf);
+ if (nr == 0)
+ return BTRFS_LEAF_DATA_SIZE(fs_info);
+ return btrfs_item_offset_nr(leaf, nr - 1);
+}
+
+enum btrfs_tree_block_status
+btrfs_check_node(struct btrfs_root *root, struct btrfs_disk_key *parent_key,
+ struct extent_buffer *buf)
+{
+ int i;
+ struct btrfs_key cpukey;
+ struct btrfs_disk_key key;
+ u32 nritems = btrfs_header_nritems(buf);
+ enum btrfs_tree_block_status ret = BTRFS_TREE_BLOCK_INVALID_NRITEMS;
+
+ if (nritems == 0 || nritems > BTRFS_NODEPTRS_PER_BLOCK(root->fs_info))
+ goto fail;
+
+ ret = BTRFS_TREE_BLOCK_INVALID_PARENT_KEY;
+ if (parent_key && parent_key->type) {
+ btrfs_node_key(buf, &key, 0);
+ if (memcmp(parent_key, &key, sizeof(key)))
+ goto fail;
+ }
+ ret = BTRFS_TREE_BLOCK_BAD_KEY_ORDER;
+ for (i = 0; nritems > 1 && i < nritems - 2; i++) {
+ btrfs_node_key(buf, &key, i);
+ btrfs_node_key_to_cpu(buf, &cpukey, i + 1);
+ if (btrfs_comp_keys(&key, &cpukey) >= 0)
+ goto fail;
+ }
+ return BTRFS_TREE_BLOCK_CLEAN;
+fail:
+ if (btrfs_header_owner(buf) == BTRFS_EXTENT_TREE_OBJECTID) {
+ if (parent_key)
+ btrfs_disk_key_to_cpu(&cpukey, parent_key);
+ else
+ btrfs_node_key_to_cpu(buf, &cpukey, 0);
+ btrfs_add_corrupt_extent_record(root->fs_info, &cpukey,
+ buf->start, buf->len,
+ btrfs_header_level(buf));
+ }
+ return ret;
+}
+
+enum btrfs_tree_block_status
+btrfs_check_leaf(struct btrfs_root *root, struct btrfs_disk_key *parent_key,
+ struct extent_buffer *buf)
+{
+ int i;
+ struct btrfs_key cpukey;
+ struct btrfs_disk_key key;
+ u32 nritems = btrfs_header_nritems(buf);
+ enum btrfs_tree_block_status ret = BTRFS_TREE_BLOCK_INVALID_NRITEMS;
+
+ if (nritems * sizeof(struct btrfs_item) > buf->len) {
+ fprintf(stderr, "invalid number of items %llu\n",
+ (unsigned long long)buf->start);
+ goto fail;
+ }
+
+ if (btrfs_header_level(buf) != 0) {
+ ret = BTRFS_TREE_BLOCK_INVALID_LEVEL;
+ fprintf(stderr, "leaf is not a leaf %llu\n",
+ (unsigned long long)btrfs_header_bytenr(buf));
+ goto fail;
+ }
+ if (btrfs_leaf_free_space(root, buf) < 0) {
+ ret = BTRFS_TREE_BLOCK_INVALID_FREE_SPACE;
+ fprintf(stderr, "leaf free space incorrect %llu %d\n",
+ (unsigned long long)btrfs_header_bytenr(buf),
+ btrfs_leaf_free_space(root, buf));
+ goto fail;
+ }
+
+ if (nritems == 0)
+ return BTRFS_TREE_BLOCK_CLEAN;
+
+ btrfs_item_key(buf, &key, 0);
+ if (parent_key && parent_key->type &&
+ memcmp(parent_key, &key, sizeof(key))) {
+ ret = BTRFS_TREE_BLOCK_INVALID_PARENT_KEY;
+ fprintf(stderr, "leaf parent key incorrect %llu\n",
+ (unsigned long long)btrfs_header_bytenr(buf));
+ goto fail;
+ }
+ for (i = 0; nritems > 1 && i < nritems - 1; i++) {
+ btrfs_item_key(buf, &key, i);
+ btrfs_item_key_to_cpu(buf, &cpukey, i + 1);
+ if (btrfs_comp_keys(&key, &cpukey) >= 0) {
+ ret = BTRFS_TREE_BLOCK_BAD_KEY_ORDER;
+ fprintf(stderr, "bad key ordering %d %d\n", i, i+1);
+ goto fail;
+ }
+ if (btrfs_item_offset_nr(buf, i) !=
+ btrfs_item_end_nr(buf, i + 1)) {
+ ret = BTRFS_TREE_BLOCK_INVALID_OFFSETS;
+ fprintf(stderr, "incorrect offsets %u %u\n",
+ btrfs_item_offset_nr(buf, i),
+ btrfs_item_end_nr(buf, i + 1));
+ goto fail;
+ }
+ if (i == 0 && btrfs_item_end_nr(buf, i) !=
+ BTRFS_LEAF_DATA_SIZE(root->fs_info)) {
+ ret = BTRFS_TREE_BLOCK_INVALID_OFFSETS;
+ fprintf(stderr, "bad item end %u wanted %u\n",
+ btrfs_item_end_nr(buf, i),
+ (unsigned)BTRFS_LEAF_DATA_SIZE(root->fs_info));
+ goto fail;
+ }
+ }
+
+ for (i = 0; i < nritems; i++) {
+ if (btrfs_item_end_nr(buf, i) >
+ BTRFS_LEAF_DATA_SIZE(root->fs_info)) {
+ btrfs_item_key(buf, &key, 0);
+ btrfs_print_key(&key);
+ fflush(stdout);
+ ret = BTRFS_TREE_BLOCK_INVALID_OFFSETS;
+ fprintf(stderr, "slot end outside of leaf %llu > %llu\n",
+ (unsigned long long)btrfs_item_end_nr(buf, i),
+ (unsigned long long)BTRFS_LEAF_DATA_SIZE(
+ root->fs_info));
+ goto fail;
+ }
+ }
+
+ return BTRFS_TREE_BLOCK_CLEAN;
+fail:
+ if (btrfs_header_owner(buf) == BTRFS_EXTENT_TREE_OBJECTID) {
+ if (parent_key)
+ btrfs_disk_key_to_cpu(&cpukey, parent_key);
+ else
+ btrfs_item_key_to_cpu(buf, &cpukey, 0);
+
+ btrfs_add_corrupt_extent_record(root->fs_info, &cpukey,
+ buf->start, buf->len, 0);
+ }
+ return ret;
+}
+
+static int noinline check_block(struct btrfs_root *root,
+ struct btrfs_path *path, int level)
+{
+ struct btrfs_disk_key key;
+ struct btrfs_disk_key *key_ptr = NULL;
+ struct extent_buffer *parent;
+ enum btrfs_tree_block_status ret;
+
+ if (path->skip_check_block)
+ return 0;
+ if (path->nodes[level + 1]) {
+ parent = path->nodes[level + 1];
+ btrfs_node_key(parent, &key, path->slots[level + 1]);
+ key_ptr = &key;
+ }
+ if (level == 0)
+ ret = btrfs_check_leaf(root, key_ptr, path->nodes[0]);
+ else
+ ret = btrfs_check_node(root, key_ptr, path->nodes[level]);
+ if (ret == BTRFS_TREE_BLOCK_CLEAN)
+ return 0;
+ return -EIO;
+}
+
+/*
+ * search for key in the extent_buffer. The items start at offset p,
+ * and they are item_size apart. There are 'max' items in p.
+ *
* the slot in the array is returned via slot, and it points to
* the place where you would insert key if it is not found in
* the array.
*
* slot may point to max if the key is bigger than all of the keys
*/
-int generic_bin_search(char *p, int item_size, struct key *key,
- int max, int *slot)
+static int generic_bin_search(struct extent_buffer *eb, unsigned long p,
+ int item_size, struct btrfs_key *key,
+ int max, int *slot)
{
int low = 0;
int high = max;
int mid;
int ret;
- struct key *tmp;
+ unsigned long offset;
+ struct btrfs_disk_key *tmp;
while(low < high) {
mid = (low + high) / 2;
- tmp = (struct key *)(p + mid * item_size);
- ret = comp_keys(tmp, key);
+ offset = p + mid * item_size;
+
+ tmp = (struct btrfs_disk_key *)(eb->data + offset);
+ ret = btrfs_comp_keys(tmp, key);
if (ret < 0)
low = mid + 1;
return 1;
}
-int bin_search(struct node *c, struct key *key, int *slot)
-{
- if (is_leaf(c->header.flags)) {
- struct leaf *l = (struct leaf *)c;
- return generic_bin_search((void *)l->items, sizeof(struct item),
- key, c->header.nritems, slot);
- } else {
- return generic_bin_search((void *)c->keys, sizeof(struct key),
- key, c->header.nritems, slot);
- }
- return -1;
-}
-
/*
- * look for key in the tree. path is filled in with nodes along the way
- * if key is found, we return zero and you can find the item in the leaf
- * level of the path (level 0)
- *
- * If the key isn't found, the path points to the slot where it should
- * be inserted.
+ * simple bin_search frontend that does the right thing for
+ * leaves vs nodes
*/
-int search_slot(struct ctree_root *root, struct key *key, struct ctree_path *p)
+static int bin_search(struct extent_buffer *eb, struct btrfs_key *key,
+ int level, int *slot)
{
- struct tree_buffer *b = root->node;
- struct node *c;
-
- int slot;
- int ret;
- int level;
- b->count++;
- while (b) {
- c = &b->node;
- level = node_level(c->header.flags);
- p->nodes[level] = b;
- ret = bin_search(c, key, &slot);
- if (!is_leaf(c->header.flags)) {
- if (ret && slot > 0)
- slot -= 1;
- p->slots[level] = slot;
- b = read_tree_block(root, c->blockptrs[slot]);
- continue;
- } else {
- p->slots[level] = slot;
- return ret;
- }
- }
- return -1;
+ if (level == 0)
+ return generic_bin_search(eb,
+ offsetof(struct btrfs_leaf, items),
+ sizeof(struct btrfs_item),
+ key, btrfs_header_nritems(eb),
+ slot);
+ else
+ return generic_bin_search(eb,
+ offsetof(struct btrfs_node, ptrs),
+ sizeof(struct btrfs_key_ptr),
+ key, btrfs_header_nritems(eb),
+ slot);
}
-/*
- * adjust the pointers going up the tree, starting at level
- * making sure the right key of each node is points to 'key'.
- * This is used after shifting pointers to the left, so it stops
- * fixing up pointers when a given leaf/node is not in slot 0 of the
- * higher levels
- */
-static void fixup_low_keys(struct ctree_root *root,
- struct ctree_path *path, struct key *key,
- int level)
+struct extent_buffer *read_node_slot(struct btrfs_fs_info *fs_info,
+ struct extent_buffer *parent, int slot)
{
- int i;
- for (i = level; i < MAX_LEVEL; i++) {
- struct node *t;
- int tslot = path->slots[i];
- if (!path->nodes[i])
- break;
- t = &path->nodes[i]->node;
- memcpy(t->keys + tslot, key, sizeof(*key));
- write_tree_block(root, path->nodes[i]);
- if (tslot != 0)
- break;
- }
+ int level = btrfs_header_level(parent);
+ if (slot < 0)
+ return NULL;
+ if (slot >= btrfs_header_nritems(parent))
+ return NULL;
+
+ if (level == 0)
+ return NULL;
+
+ return read_tree_block(fs_info, btrfs_node_blockptr(parent, slot),
+ btrfs_node_ptr_generation(parent, slot));
}
-/*
- * try to push data from one node into the next node left in the
- * tree. The src node is found at specified level in the path.
- * If some bytes were pushed, return 0, otherwise return 1.
- *
- * Lower nodes/leaves in the path are not touched, higher nodes may
- * be modified to reflect the push.
- *
- * The path is altered to reflect the push.
- */
-int push_node_left(struct ctree_root *root, struct ctree_path *path, int level)
+static int balance_level(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path, int level)
{
- int slot;
- struct node *left;
- struct node *right;
- int push_items = 0;
- int left_nritems;
- int right_nritems;
- struct tree_buffer *t;
- struct tree_buffer *right_buf;
+ struct extent_buffer *right = NULL;
+ struct extent_buffer *mid;
+ struct extent_buffer *left = NULL;
+ struct extent_buffer *parent = NULL;
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ int ret = 0;
+ int wret;
+ int pslot;
+ int orig_slot = path->slots[level];
+ u64 orig_ptr;
+
+ if (level == 0)
+ return 0;
- if (level == MAX_LEVEL - 1 || path->nodes[level + 1] == 0)
- return 1;
- slot = path->slots[level + 1];
- if (slot == 0)
- return 1;
+ mid = path->nodes[level];
+ WARN_ON(btrfs_header_generation(mid) != trans->transid);
- t = read_tree_block(root,
- path->nodes[level + 1]->node.blockptrs[slot - 1]);
- left = &t->node;
- right_buf = path->nodes[level];
- right = &right_buf->node;
- left_nritems = left->header.nritems;
- right_nritems = right->header.nritems;
- push_items = NODEPTRS_PER_BLOCK - (left_nritems + 1);
- if (push_items <= 0) {
- tree_block_release(root, t);
- return 1;
+ orig_ptr = btrfs_node_blockptr(mid, orig_slot);
+
+ if (level < BTRFS_MAX_LEVEL - 1) {
+ parent = path->nodes[level + 1];
+ pslot = path->slots[level + 1];
}
- if (right_nritems < push_items)
- push_items = right_nritems;
- memcpy(left->keys + left_nritems, right->keys,
- push_items * sizeof(struct key));
- memcpy(left->blockptrs + left_nritems, right->blockptrs,
- push_items * sizeof(u64));
- memmove(right->keys, right->keys + push_items,
- (right_nritems - push_items) * sizeof(struct key));
- memmove(right->blockptrs, right->blockptrs + push_items,
- (right_nritems - push_items) * sizeof(u64));
- right->header.nritems -= push_items;
- left->header.nritems += push_items;
+ /*
+ * deal with the case where there is only one pointer in the root
+ * by promoting the node below to a root
+ */
+ if (!parent) {
+ struct extent_buffer *child;
- /* adjust the pointers going up the tree */
- fixup_low_keys(root, path, right->keys, level + 1);
+ if (btrfs_header_nritems(mid) != 1)
+ return 0;
- write_tree_block(root, t);
- write_tree_block(root, right_buf);
+ /* promote the child to a root */
+ child = read_node_slot(fs_info, mid, 0);
+ BUG_ON(!extent_buffer_uptodate(child));
+ ret = btrfs_cow_block(trans, root, child, mid, 0, &child);
+ BUG_ON(ret);
+
+ root->node = child;
+ add_root_to_dirty_list(root);
+ path->nodes[level] = NULL;
+ clean_tree_block(trans, root, mid);
+ /* once for the path */
+ free_extent_buffer(mid);
+
+ ret = btrfs_free_extent(trans, root, mid->start, mid->len,
+ 0, root->root_key.objectid,
+ level, 1);
+ /* once for the root ptr */
+ free_extent_buffer(mid);
+ return ret;
+ }
+ if (btrfs_header_nritems(mid) >
+ BTRFS_NODEPTRS_PER_BLOCK(fs_info) / 4)
+ return 0;
- /* then fixup the leaf pointer in the path */
- if (path->slots[level] < push_items) {
- path->slots[level] += left_nritems;
- tree_block_release(root, path->nodes[level]);
- path->nodes[level] = t;
- path->slots[level + 1] -= 1;
+ left = read_node_slot(fs_info, parent, pslot - 1);
+ if (extent_buffer_uptodate(left)) {
+ wret = btrfs_cow_block(trans, root, left,
+ parent, pslot - 1, &left);
+ if (wret) {
+ ret = wret;
+ goto enospc;
+ }
+ }
+ right = read_node_slot(fs_info, parent, pslot + 1);
+ if (extent_buffer_uptodate(right)) {
+ wret = btrfs_cow_block(trans, root, right,
+ parent, pslot + 1, &right);
+ if (wret) {
+ ret = wret;
+ goto enospc;
+ }
+ }
+
+ /* first, try to make some room in the middle buffer */
+ if (left) {
+ orig_slot += btrfs_header_nritems(left);
+ wret = push_node_left(trans, root, left, mid, 1);
+ if (wret < 0)
+ ret = wret;
+ }
+
+ /*
+ * then try to empty the right most buffer into the middle
+ */
+ if (right) {
+ wret = push_node_left(trans, root, mid, right, 1);
+ if (wret < 0 && wret != -ENOSPC)
+ ret = wret;
+ if (btrfs_header_nritems(right) == 0) {
+ u64 bytenr = right->start;
+ u32 blocksize = right->len;
+
+ clean_tree_block(trans, root, right);
+ free_extent_buffer(right);
+ right = NULL;
+ wret = btrfs_del_ptr(root, path, level + 1, pslot + 1);
+ if (wret)
+ ret = wret;
+ wret = btrfs_free_extent(trans, root, bytenr,
+ blocksize, 0,
+ root->root_key.objectid,
+ level, 0);
+ if (wret)
+ ret = wret;
+ } else {
+ struct btrfs_disk_key right_key;
+ btrfs_node_key(right, &right_key, 0);
+ btrfs_set_node_key(parent, &right_key, pslot + 1);
+ btrfs_mark_buffer_dirty(parent);
+ }
+ }
+ if (btrfs_header_nritems(mid) == 1) {
+ /*
+ * we're not allowed to leave a node with one item in the
+ * tree during a delete. A deletion from lower in the tree
+ * could try to delete the only pointer in this node.
+ * So, pull some keys from the left.
+ * There has to be a left pointer at this point because
+ * otherwise we would have pulled some pointers from the
+ * right
+ */
+ BUG_ON(!left);
+ wret = balance_node_right(trans, root, mid, left);
+ if (wret < 0) {
+ ret = wret;
+ goto enospc;
+ }
+ if (wret == 1) {
+ wret = push_node_left(trans, root, left, mid, 1);
+ if (wret < 0)
+ ret = wret;
+ }
+ BUG_ON(wret == 1);
+ }
+ if (btrfs_header_nritems(mid) == 0) {
+ /* we've managed to empty the middle node, drop it */
+ u64 bytenr = mid->start;
+ u32 blocksize = mid->len;
+ clean_tree_block(trans, root, mid);
+ free_extent_buffer(mid);
+ mid = NULL;
+ wret = btrfs_del_ptr(root, path, level + 1, pslot);
+ if (wret)
+ ret = wret;
+ wret = btrfs_free_extent(trans, root, bytenr, blocksize,
+ 0, root->root_key.objectid,
+ level, 0);
+ if (wret)
+ ret = wret;
} else {
- path->slots[level] -= push_items;
- tree_block_release(root, t);
+ /* update the parent key to reflect our changes */
+ struct btrfs_disk_key mid_key;
+ btrfs_node_key(mid, &mid_key, 0);
+ btrfs_set_node_key(parent, &mid_key, pslot);
+ btrfs_mark_buffer_dirty(parent);
}
- return 0;
+
+ /* update the path */
+ if (left) {
+ if (btrfs_header_nritems(left) > orig_slot) {
+ extent_buffer_get(left);
+ path->nodes[level] = left;
+ path->slots[level + 1] -= 1;
+ path->slots[level] = orig_slot;
+ if (mid)
+ free_extent_buffer(mid);
+ } else {
+ orig_slot -= btrfs_header_nritems(left);
+ path->slots[level] = orig_slot;
+ }
+ }
+ /* double check we haven't messed things up */
+ check_block(root, path, level);
+ if (orig_ptr !=
+ btrfs_node_blockptr(path->nodes[level], path->slots[level]))
+ BUG();
+enospc:
+ if (right)
+ free_extent_buffer(right);
+ if (left)
+ free_extent_buffer(left);
+ return ret;
}
-/*
- * try to push data from one node into the next node right in the
- * tree. The src node is found at specified level in the path.
- * If some bytes were pushed, return 0, otherwise return 1.
- *
- * Lower nodes/leaves in the path are not touched, higher nodes may
- * be modified to reflect the push.
- *
- * The path is altered to reflect the push.
- */
-int push_node_right(struct ctree_root *root, struct ctree_path *path, int level)
+/* returns zero if the push worked, non-zero otherwise */
+static int noinline push_nodes_for_insert(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path, int level)
{
- int slot;
- struct tree_buffer *t;
- struct tree_buffer *src_buffer;
- struct node *dst;
- struct node *src;
- int push_items = 0;
- int dst_nritems;
- int src_nritems;
-
- /* can't push from the root */
- if (level == MAX_LEVEL - 1 || path->nodes[level + 1] == 0)
- return 1;
-
- /* only try to push inside the node higher up */
- slot = path->slots[level + 1];
- if (slot == NODEPTRS_PER_BLOCK - 1)
+ struct extent_buffer *right = NULL;
+ struct extent_buffer *mid;
+ struct extent_buffer *left = NULL;
+ struct extent_buffer *parent = NULL;
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ int ret = 0;
+ int wret;
+ int pslot;
+ int orig_slot = path->slots[level];
+
+ if (level == 0)
return 1;
- if (slot >= path->nodes[level + 1]->node.header.nritems -1)
- return 1;
+ mid = path->nodes[level];
+ WARN_ON(btrfs_header_generation(mid) != trans->transid);
- t = read_tree_block(root,
- path->nodes[level + 1]->node.blockptrs[slot + 1]);
- dst = &t->node;
- src_buffer = path->nodes[level];
- src = &src_buffer->node;
- dst_nritems = dst->header.nritems;
- src_nritems = src->header.nritems;
- push_items = NODEPTRS_PER_BLOCK - (dst_nritems + 1);
- if (push_items <= 0) {
- tree_block_release(root, t);
- return 1;
+ if (level < BTRFS_MAX_LEVEL - 1) {
+ parent = path->nodes[level + 1];
+ pslot = path->slots[level + 1];
}
- if (src_nritems < push_items)
- push_items = src_nritems;
- memmove(dst->keys + push_items, dst->keys,
- dst_nritems * sizeof(struct key));
- memcpy(dst->keys, src->keys + src_nritems - push_items,
- push_items * sizeof(struct key));
-
- memmove(dst->blockptrs + push_items, dst->blockptrs,
- dst_nritems * sizeof(u64));
- memcpy(dst->blockptrs, src->blockptrs + src_nritems - push_items,
- push_items * sizeof(u64));
-
- src->header.nritems -= push_items;
- dst->header.nritems += push_items;
+ if (!parent)
+ return 1;
- /* adjust the pointers going up the tree */
- memcpy(path->nodes[level + 1]->node.keys + path->slots[level + 1] + 1,
- dst->keys, sizeof(struct key));
+ left = read_node_slot(fs_info, parent, pslot - 1);
- write_tree_block(root, path->nodes[level + 1]);
- write_tree_block(root, t);
- write_tree_block(root, src_buffer);
+ /* first, try to make some room in the middle buffer */
+ if (extent_buffer_uptodate(left)) {
+ u32 left_nr;
+ left_nr = btrfs_header_nritems(left);
+ if (left_nr >= BTRFS_NODEPTRS_PER_BLOCK(fs_info) - 1) {
+ wret = 1;
+ } else {
+ ret = btrfs_cow_block(trans, root, left, parent,
+ pslot - 1, &left);
+ if (ret)
+ wret = 1;
+ else {
+ wret = push_node_left(trans, root,
+ left, mid, 0);
+ }
+ }
+ if (wret < 0)
+ ret = wret;
+ if (wret == 0) {
+ struct btrfs_disk_key disk_key;
+ orig_slot += left_nr;
+ btrfs_node_key(mid, &disk_key, 0);
+ btrfs_set_node_key(parent, &disk_key, pslot);
+ btrfs_mark_buffer_dirty(parent);
+ if (btrfs_header_nritems(left) > orig_slot) {
+ path->nodes[level] = left;
+ path->slots[level + 1] -= 1;
+ path->slots[level] = orig_slot;
+ free_extent_buffer(mid);
+ } else {
+ orig_slot -=
+ btrfs_header_nritems(left);
+ path->slots[level] = orig_slot;
+ free_extent_buffer(left);
+ }
+ return 0;
+ }
+ free_extent_buffer(left);
+ }
+ right= read_node_slot(fs_info, parent, pslot + 1);
- /* then fixup the pointers in the path */
- if (path->slots[level] >= src->header.nritems) {
- path->slots[level] -= src->header.nritems;
- tree_block_release(root, path->nodes[level]);
- path->nodes[level] = t;
- path->slots[level + 1] += 1;
- } else {
- tree_block_release(root, t);
+ /*
+ * then try to empty the right most buffer into the middle
+ */
+ if (extent_buffer_uptodate(right)) {
+ u32 right_nr;
+ right_nr = btrfs_header_nritems(right);
+ if (right_nr >= BTRFS_NODEPTRS_PER_BLOCK(root->fs_info) - 1) {
+ wret = 1;
+ } else {
+ ret = btrfs_cow_block(trans, root, right,
+ parent, pslot + 1,
+ &right);
+ if (ret)
+ wret = 1;
+ else {
+ wret = balance_node_right(trans, root,
+ right, mid);
+ }
+ }
+ if (wret < 0)
+ ret = wret;
+ if (wret == 0) {
+ struct btrfs_disk_key disk_key;
+
+ btrfs_node_key(right, &disk_key, 0);
+ btrfs_set_node_key(parent, &disk_key, pslot + 1);
+ btrfs_mark_buffer_dirty(parent);
+
+ if (btrfs_header_nritems(mid) <= orig_slot) {
+ path->nodes[level] = right;
+ path->slots[level + 1] += 1;
+ path->slots[level] = orig_slot -
+ btrfs_header_nritems(mid);
+ free_extent_buffer(mid);
+ } else {
+ free_extent_buffer(right);
+ }
+ return 0;
+ }
+ free_extent_buffer(right);
+ }
+ return 1;
+}
+
+/*
+ * readahead one full node of leaves
+ */
+void reada_for_search(struct btrfs_root *root, struct btrfs_path *path,
+ int level, int slot, u64 objectid)
+{
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ struct extent_buffer *node;
+ struct btrfs_disk_key disk_key;
+ u32 nritems;
+ u64 search;
+ u64 lowest_read;
+ u64 highest_read;
+ u64 nread = 0;
+ int direction = path->reada;
+ struct extent_buffer *eb;
+ u32 nr;
+ u32 nscan = 0;
+
+ if (level != 1)
+ return;
+
+ if (!path->nodes[level])
+ return;
+
+ node = path->nodes[level];
+ search = btrfs_node_blockptr(node, slot);
+ eb = btrfs_find_tree_block(fs_info, search, fs_info->nodesize);
+ if (eb) {
+ free_extent_buffer(eb);
+ return;
+ }
+
+ highest_read = search;
+ lowest_read = search;
+
+ nritems = btrfs_header_nritems(node);
+ nr = slot;
+ while(1) {
+ if (direction < 0) {
+ if (nr == 0)
+ break;
+ nr--;
+ } else if (direction > 0) {
+ nr++;
+ if (nr >= nritems)
+ break;
+ }
+ if (path->reada < 0 && objectid) {
+ btrfs_node_key(node, &disk_key, nr);
+ if (btrfs_disk_key_objectid(&disk_key) != objectid)
+ break;
+ }
+ search = btrfs_node_blockptr(node, nr);
+ if ((search >= lowest_read && search <= highest_read) ||
+ (search < lowest_read && lowest_read - search <= 32768) ||
+ (search > highest_read && search - highest_read <= 32768)) {
+ readahead_tree_block(fs_info, search,
+ btrfs_node_ptr_generation(node, nr));
+ nread += fs_info->nodesize;
+ }
+ nscan++;
+ if (path->reada < 2 && (nread > SZ_256K || nscan > 32))
+ break;
+ if(nread > SZ_1M || nscan > 128)
+ break;
+
+ if (search < lowest_read)
+ lowest_read = search;
+ if (search > highest_read)
+ highest_read = search;
+ }
+}
+
+int btrfs_find_item(struct btrfs_root *fs_root, struct btrfs_path *found_path,
+ u64 iobjectid, u64 ioff, u8 key_type,
+ struct btrfs_key *found_key)
+{
+ int ret;
+ struct btrfs_key key;
+ struct extent_buffer *eb;
+ struct btrfs_path *path;
+
+ key.type = key_type;
+ key.objectid = iobjectid;
+ key.offset = ioff;
+
+ if (found_path == NULL) {
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+ } else
+ path = found_path;
+
+ ret = btrfs_search_slot(NULL, fs_root, &key, path, 0, 0);
+ if ((ret < 0) || (found_key == NULL))
+ goto out;
+
+ eb = path->nodes[0];
+ if (ret && path->slots[0] >= btrfs_header_nritems(eb)) {
+ ret = btrfs_next_leaf(fs_root, path);
+ if (ret)
+ goto out;
+ eb = path->nodes[0];
+ }
+
+ btrfs_item_key_to_cpu(eb, found_key, path->slots[0]);
+ if (found_key->type != key.type ||
+ found_key->objectid != key.objectid) {
+ ret = 1;
+ goto out;
+ }
+
+out:
+ if (path != found_path)
+ btrfs_free_path(path);
+ return ret;
+}
+
+/*
+ * look for key in the tree. path is filled in with nodes along the way
+ * if key is found, we return zero and you can find the item in the leaf
+ * level of the path (level 0)
+ *
+ * If the key isn't found, the path points to the slot where it should
+ * be inserted, and 1 is returned. If there are other errors during the
+ * search a negative error number is returned.
+ *
+ * if ins_len > 0, nodes and leaves will be split as we walk down the
+ * tree. if ins_len < 0, nodes will be merged as we walk down the tree (if
+ * possible)
+ */
+int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root
+ *root, struct btrfs_key *key, struct btrfs_path *p, int
+ ins_len, int cow)
+{
+ struct extent_buffer *b;
+ int slot;
+ int ret;
+ int level;
+ int should_reada = p->reada;
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ u8 lowest_level = 0;
+
+ lowest_level = p->lowest_level;
+ WARN_ON(lowest_level && ins_len > 0);
+ WARN_ON(p->nodes[0] != NULL);
+ /*
+ WARN_ON(!mutex_is_locked(&root->fs_info->fs_mutex));
+ */
+again:
+ b = root->node;
+ extent_buffer_get(b);
+ while (b) {
+ level = btrfs_header_level(b);
+ if (cow) {
+ int wret;
+ wret = btrfs_cow_block(trans, root, b,
+ p->nodes[level + 1],
+ p->slots[level + 1],
+ &b);
+ if (wret) {
+ free_extent_buffer(b);
+ return wret;
+ }
+ }
+ BUG_ON(!cow && ins_len);
+ if (level != btrfs_header_level(b))
+ WARN_ON(1);
+ level = btrfs_header_level(b);
+ p->nodes[level] = b;
+ ret = check_block(root, p, level);
+ if (ret)
+ return -1;
+ ret = bin_search(b, key, level, &slot);
+ if (level != 0) {
+ if (ret && slot > 0)
+ slot -= 1;
+ p->slots[level] = slot;
+ if ((p->search_for_split || ins_len > 0) &&
+ btrfs_header_nritems(b) >=
+ BTRFS_NODEPTRS_PER_BLOCK(fs_info) - 3) {
+ int sret = split_node(trans, root, p, level);
+ BUG_ON(sret > 0);
+ if (sret)
+ return sret;
+ b = p->nodes[level];
+ slot = p->slots[level];
+ } else if (ins_len < 0) {
+ int sret = balance_level(trans, root, p,
+ level);
+ if (sret)
+ return sret;
+ b = p->nodes[level];
+ if (!b) {
+ btrfs_release_path(p);
+ goto again;
+ }
+ slot = p->slots[level];
+ BUG_ON(btrfs_header_nritems(b) == 1);
+ }
+ /* this is only true while dropping a snapshot */
+ if (level == lowest_level)
+ break;
+
+ if (should_reada)
+ reada_for_search(root, p, level, slot,
+ key->objectid);
+
+ b = read_node_slot(fs_info, b, slot);
+ if (!extent_buffer_uptodate(b))
+ return -EIO;
+ } else {
+ p->slots[level] = slot;
+ if (ins_len > 0 &&
+ ins_len > btrfs_leaf_free_space(root, b)) {
+ int sret = split_leaf(trans, root, key,
+ p, ins_len, ret == 0);
+ BUG_ON(sret > 0);
+ if (sret)
+ return sret;
+ }
+ return ret;
+ }
+ }
+ return 1;
+}
+
+/*
+ * adjust the pointers going up the tree, starting at level
+ * making sure the right key of each node is points to 'key'.
+ * This is used after shifting pointers to the left, so it stops
+ * fixing up pointers when a given leaf/node is not in slot 0 of the
+ * higher levels
+ */
+void btrfs_fixup_low_keys(struct btrfs_root *root, struct btrfs_path *path,
+ struct btrfs_disk_key *key, int level)
+{
+ int i;
+ struct extent_buffer *t;
+
+ for (i = level; i < BTRFS_MAX_LEVEL; i++) {
+ int tslot = path->slots[i];
+ if (!path->nodes[i])
+ break;
+ t = path->nodes[i];
+ btrfs_set_node_key(t, key, tslot);
+ btrfs_mark_buffer_dirty(path->nodes[i]);
+ if (tslot != 0)
+ break;
}
+}
+
+/*
+ * update item key.
+ *
+ * This function isn't completely safe. It's the caller's responsibility
+ * that the new key won't break the order
+ */
+int btrfs_set_item_key_safe(struct btrfs_root *root, struct btrfs_path *path,
+ struct btrfs_key *new_key)
+{
+ struct btrfs_disk_key disk_key;
+ struct extent_buffer *eb;
+ int slot;
+
+ eb = path->nodes[0];
+ slot = path->slots[0];
+ if (slot > 0) {
+ btrfs_item_key(eb, &disk_key, slot - 1);
+ if (btrfs_comp_keys(&disk_key, new_key) >= 0)
+ return -1;
+ }
+ if (slot < btrfs_header_nritems(eb) - 1) {
+ btrfs_item_key(eb, &disk_key, slot + 1);
+ if (btrfs_comp_keys(&disk_key, new_key) <= 0)
+ return -1;
+ }
+
+ btrfs_cpu_key_to_disk(&disk_key, new_key);
+ btrfs_set_item_key(eb, &disk_key, slot);
+ btrfs_mark_buffer_dirty(eb);
+ if (slot == 0)
+ btrfs_fixup_low_keys(root, path, &disk_key, 1);
+ return 0;
+}
+
+/*
+ * update an item key without the safety checks. This is meant to be called by
+ * fsck only.
+ */
+void btrfs_set_item_key_unsafe(struct btrfs_root *root,
+ struct btrfs_path *path,
+ struct btrfs_key *new_key)
+{
+ struct btrfs_disk_key disk_key;
+ struct extent_buffer *eb;
+ int slot;
+
+ eb = path->nodes[0];
+ slot = path->slots[0];
+
+ btrfs_cpu_key_to_disk(&disk_key, new_key);
+ btrfs_set_item_key(eb, &disk_key, slot);
+ btrfs_mark_buffer_dirty(eb);
+ if (slot == 0)
+ btrfs_fixup_low_keys(root, path, &disk_key, 1);
+}
+
+/*
+ * try to push data from one node into the next node left in the
+ * tree.
+ *
+ * returns 0 if some ptrs were pushed left, < 0 if there was some horrible
+ * error, and > 0 if there was no room in the left hand block.
+ */
+static int push_node_left(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, struct extent_buffer *dst,
+ struct extent_buffer *src, int empty)
+{
+ int push_items = 0;
+ int src_nritems;
+ int dst_nritems;
+ int ret = 0;
+
+ src_nritems = btrfs_header_nritems(src);
+ dst_nritems = btrfs_header_nritems(dst);
+ push_items = BTRFS_NODEPTRS_PER_BLOCK(root->fs_info) - dst_nritems;
+ WARN_ON(btrfs_header_generation(src) != trans->transid);
+ WARN_ON(btrfs_header_generation(dst) != trans->transid);
+
+ if (!empty && src_nritems <= 8)
+ return 1;
+
+ if (push_items <= 0) {
+ return 1;
+ }
+
+ if (empty) {
+ push_items = min(src_nritems, push_items);
+ if (push_items < src_nritems) {
+ /* leave at least 8 pointers in the node if
+ * we aren't going to empty it
+ */
+ if (src_nritems - push_items < 8) {
+ if (push_items <= 8)
+ return 1;
+ push_items -= 8;
+ }
+ }
+ } else
+ push_items = min(src_nritems - 8, push_items);
+
+ copy_extent_buffer(dst, src,
+ btrfs_node_key_ptr_offset(dst_nritems),
+ btrfs_node_key_ptr_offset(0),
+ push_items * sizeof(struct btrfs_key_ptr));
+
+ if (push_items < src_nritems) {
+ memmove_extent_buffer(src, btrfs_node_key_ptr_offset(0),
+ btrfs_node_key_ptr_offset(push_items),
+ (src_nritems - push_items) *
+ sizeof(struct btrfs_key_ptr));
+ }
+ btrfs_set_header_nritems(src, src_nritems - push_items);
+ btrfs_set_header_nritems(dst, dst_nritems + push_items);
+ btrfs_mark_buffer_dirty(src);
+ btrfs_mark_buffer_dirty(dst);
+
+ return ret;
+}
+
+/*
+ * try to push data from one node into the next node right in the
+ * tree.
+ *
+ * returns 0 if some ptrs were pushed, < 0 if there was some horrible
+ * error, and > 0 if there was no room in the right hand block.
+ *
+ * this will only push up to 1/2 the contents of the left node over
+ */
+static int balance_node_right(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct extent_buffer *dst,
+ struct extent_buffer *src)
+{
+ int push_items = 0;
+ int max_push;
+ int src_nritems;
+ int dst_nritems;
+ int ret = 0;
+
+ WARN_ON(btrfs_header_generation(src) != trans->transid);
+ WARN_ON(btrfs_header_generation(dst) != trans->transid);
+
+ src_nritems = btrfs_header_nritems(src);
+ dst_nritems = btrfs_header_nritems(dst);
+ push_items = BTRFS_NODEPTRS_PER_BLOCK(root->fs_info) - dst_nritems;
+ if (push_items <= 0) {
+ return 1;
+ }
+
+ if (src_nritems < 4) {
+ return 1;
+ }
+
+ max_push = src_nritems / 2 + 1;
+ /* don't try to empty the node */
+ if (max_push >= src_nritems) {
+ return 1;
+ }
+
+ if (max_push < push_items)
+ push_items = max_push;
+
+ memmove_extent_buffer(dst, btrfs_node_key_ptr_offset(push_items),
+ btrfs_node_key_ptr_offset(0),
+ (dst_nritems) *
+ sizeof(struct btrfs_key_ptr));
+
+ copy_extent_buffer(dst, src,
+ btrfs_node_key_ptr_offset(0),
+ btrfs_node_key_ptr_offset(src_nritems - push_items),
+ push_items * sizeof(struct btrfs_key_ptr));
+
+ btrfs_set_header_nritems(src, src_nritems - push_items);
+ btrfs_set_header_nritems(dst, dst_nritems + push_items);
+
+ btrfs_mark_buffer_dirty(src);
+ btrfs_mark_buffer_dirty(dst);
+
+ return ret;
+}
+
+/*
+ * helper function to insert a new root level in the tree.
+ * A new node is allocated, and a single item is inserted to
+ * point to the existing root
+ *
+ * returns zero on success or < 0 on failure.
+ */
+static int noinline insert_new_root(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path, int level)
+{
+ u64 lower_gen;
+ struct extent_buffer *lower;
+ struct extent_buffer *c;
+ struct extent_buffer *old;
+ struct btrfs_disk_key lower_key;
+
+ BUG_ON(path->nodes[level]);
+ BUG_ON(path->nodes[level-1] != root->node);
+
+ lower = path->nodes[level-1];
+ if (level == 1)
+ btrfs_item_key(lower, &lower_key, 0);
+ else
+ btrfs_node_key(lower, &lower_key, 0);
+
+ c = btrfs_alloc_free_block(trans, root, root->fs_info->nodesize,
+ root->root_key.objectid, &lower_key,
+ level, root->node->start, 0);
+
+ if (IS_ERR(c))
+ return PTR_ERR(c);
+
+ memset_extent_buffer(c, 0, 0, sizeof(struct btrfs_header));
+ btrfs_set_header_nritems(c, 1);
+ btrfs_set_header_level(c, level);
+ btrfs_set_header_bytenr(c, c->start);
+ btrfs_set_header_generation(c, trans->transid);
+ btrfs_set_header_backref_rev(c, BTRFS_MIXED_BACKREF_REV);
+ btrfs_set_header_owner(c, root->root_key.objectid);
+
+ write_extent_buffer(c, root->fs_info->fsid,
+ btrfs_header_fsid(), BTRFS_FSID_SIZE);
+
+ write_extent_buffer(c, root->fs_info->chunk_tree_uuid,
+ btrfs_header_chunk_tree_uuid(c),
+ BTRFS_UUID_SIZE);
+
+ btrfs_set_node_key(c, &lower_key, 0);
+ btrfs_set_node_blockptr(c, 0, lower->start);
+ lower_gen = btrfs_header_generation(lower);
+ WARN_ON(lower_gen != trans->transid);
+
+ btrfs_set_node_ptr_generation(c, 0, lower_gen);
+
+ btrfs_mark_buffer_dirty(c);
+
+ old = root->node;
+ root->node = c;
+
+ /* the super has an extra ref to root->node */
+ free_extent_buffer(old);
+
+ add_root_to_dirty_list(root);
+ extent_buffer_get(c);
+ path->nodes[level] = c;
+ path->slots[level] = 0;
return 0;
}
/*
* worker function to insert a single pointer in a node.
* the node should have enough room for the pointer already
+ *
* slot and level indicate where you want the key to go, and
* blocknr is the block the key points to.
+ *
+ * returns zero on success and < 0 on any error
*/
-int __insert_ptr(struct ctree_root *root,
- struct ctree_path *path, struct key *key,
- u64 blocknr, int slot, int level)
+static int insert_ptr(struct btrfs_trans_handle *trans, struct btrfs_root
+ *root, struct btrfs_path *path, struct btrfs_disk_key
+ *key, u64 bytenr, int slot, int level)
{
- struct node *c;
- struct node *lower;
- struct key *lower_key;
+ struct extent_buffer *lower;
int nritems;
- /* need a new root */
- if (!path->nodes[level]) {
- struct tree_buffer *t;
- t = alloc_free_block(root);
- c = &t->node;
- memset(c, 0, sizeof(c));
- c->header.nritems = 2;
- c->header.flags = node_level(level);
- c->header.blocknr = t->blocknr;
- c->header.parentid = root->node->node.header.parentid;
- lower = &path->nodes[level-1]->node;
- if (is_leaf(lower->header.flags))
- lower_key = &((struct leaf *)lower)->items[0].key;
- else
- lower_key = lower->keys;
- memcpy(c->keys, lower_key, sizeof(struct key));
- memcpy(c->keys + 1, key, sizeof(struct key));
- c->blockptrs[0] = path->nodes[level-1]->blocknr;
- c->blockptrs[1] = blocknr;
- /* the super has an extra ref to root->node */
- tree_block_release(root, root->node);
- root->node = t;
- t->count++;
- write_tree_block(root, t);
- path->nodes[level] = t;
- path->slots[level] = 0;
- if (c->keys[1].objectid == 0)
- BUG();
- return 0;
- }
- lower = &path->nodes[level]->node;
- nritems = lower->header.nritems;
+
+ BUG_ON(!path->nodes[level]);
+ lower = path->nodes[level];
+ nritems = btrfs_header_nritems(lower);
if (slot > nritems)
BUG();
- if (nritems == NODEPTRS_PER_BLOCK)
+ if (nritems == BTRFS_NODEPTRS_PER_BLOCK(root->fs_info))
BUG();
- if (slot != nritems) {
- memmove(lower->keys + slot + 1, lower->keys + slot,
- (nritems - slot) * sizeof(struct key));
- memmove(lower->blockptrs + slot + 1, lower->blockptrs + slot,
- (nritems - slot) * sizeof(u64));
- }
- memcpy(lower->keys + slot, key, sizeof(struct key));
- lower->blockptrs[slot] = blocknr;
- lower->header.nritems++;
- if (lower->keys[1].objectid == 0)
- BUG();
- write_tree_block(root, path->nodes[level]);
+ if (slot < nritems) {
+ /* shift the items */
+ memmove_extent_buffer(lower,
+ btrfs_node_key_ptr_offset(slot + 1),
+ btrfs_node_key_ptr_offset(slot),
+ (nritems - slot) * sizeof(struct btrfs_key_ptr));
+ }
+ btrfs_set_node_key(lower, key, slot);
+ btrfs_set_node_blockptr(lower, slot, bytenr);
+ WARN_ON(trans->transid == 0);
+ btrfs_set_node_ptr_generation(lower, slot, trans->transid);
+ btrfs_set_header_nritems(lower, nritems + 1);
+ btrfs_mark_buffer_dirty(lower);
return 0;
}
-
/*
- * insert a key,blocknr pair into the tree at a given level
- * If the node at that level in the path doesn't have room,
- * it is split or shifted as appropriate.
+ * split the node at the specified level in path in two.
+ * The path is corrected to point to the appropriate node after the split
+ *
+ * Before splitting this tries to make some room in the node by pushing
+ * left and right, if either one works, it returns right away.
+ *
+ * returns 0 on success and < 0 on failure
*/
-int insert_ptr(struct ctree_root *root,
- struct ctree_path *path, struct key *key,
- u64 blocknr, int level)
+static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root
+ *root, struct btrfs_path *path, int level)
{
- struct tree_buffer *t = path->nodes[level];
- struct node *c = &path->nodes[level]->node;
- struct node *b;
- struct tree_buffer *b_buffer;
- struct tree_buffer *bal[MAX_LEVEL];
- int bal_level = level;
+ struct extent_buffer *c;
+ struct extent_buffer *split;
+ struct btrfs_disk_key disk_key;
int mid;
- int bal_start = -1;
-
- /*
- * check to see if we need to make room in the node for this
- * pointer. If we do, keep walking the tree, making sure there
- * is enough room in each level for the required insertions.
- *
- * The bal array is filled in with any nodes to be inserted
- * due to splitting. Once we've done all the splitting required
- * do the inserts based on the data in the bal array.
- */
- memset(bal, 0, sizeof(bal));
- while(t && t->node.header.nritems == NODEPTRS_PER_BLOCK) {
- c = &t->node;
- if (push_node_left(root, path,
- node_level(c->header.flags)) == 0)
- break;
- if (push_node_right(root, path,
- node_level(c->header.flags)) == 0)
- break;
- bal_start = bal_level;
- if (bal_level == MAX_LEVEL - 1)
- BUG();
- b_buffer = alloc_free_block(root);
- b = &b_buffer->node;
- b->header.flags = c->header.flags;
- b->header.blocknr = b_buffer->blocknr;
- b->header.parentid = root->node->node.header.parentid;
- mid = (c->header.nritems + 1) / 2;
- memcpy(b->keys, c->keys + mid,
- (c->header.nritems - mid) * sizeof(struct key));
- memcpy(b->blockptrs, c->blockptrs + mid,
- (c->header.nritems - mid) * sizeof(u64));
- b->header.nritems = c->header.nritems - mid;
- c->header.nritems = mid;
-
- write_tree_block(root, t);
- write_tree_block(root, b_buffer);
-
- bal[bal_level] = b_buffer;
- if (bal_level == MAX_LEVEL - 1)
- break;
- bal_level += 1;
- t = path->nodes[bal_level];
+ int ret;
+ int wret;
+ u32 c_nritems;
+
+ c = path->nodes[level];
+ WARN_ON(btrfs_header_generation(c) != trans->transid);
+ if (c == root->node) {
+ /* trying to split the root, lets make a new one */
+ ret = insert_new_root(trans, root, path, level + 1);
+ if (ret)
+ return ret;
+ } else {
+ ret = push_nodes_for_insert(trans, root, path, level);
+ c = path->nodes[level];
+ if (!ret && btrfs_header_nritems(c) <
+ BTRFS_NODEPTRS_PER_BLOCK(root->fs_info) - 3)
+ return 0;
+ if (ret < 0)
+ return ret;
}
- /*
- * bal_start tells us the first level in the tree that needed to
- * be split. Go through the bal array inserting the new nodes
- * as needed. The path is fixed as we go.
- */
- while(bal_start > 0) {
- b_buffer = bal[bal_start];
- c = &path->nodes[bal_start]->node;
- __insert_ptr(root, path, b_buffer->node.keys, b_buffer->blocknr,
- path->slots[bal_start + 1] + 1, bal_start + 1);
- if (path->slots[bal_start] >= c->header.nritems) {
- path->slots[bal_start] -= c->header.nritems;
- tree_block_release(root, path->nodes[bal_start]);
- path->nodes[bal_start] = b_buffer;
- path->slots[bal_start + 1] += 1;
- } else {
- tree_block_release(root, b_buffer);
- }
- bal_start--;
- if (!bal[bal_start])
- break;
+
+ c_nritems = btrfs_header_nritems(c);
+ mid = (c_nritems + 1) / 2;
+ btrfs_node_key(c, &disk_key, mid);
+
+ split = btrfs_alloc_free_block(trans, root, root->fs_info->nodesize,
+ root->root_key.objectid,
+ &disk_key, level, c->start, 0);
+ if (IS_ERR(split))
+ return PTR_ERR(split);
+
+ memset_extent_buffer(split, 0, 0, sizeof(struct btrfs_header));
+ btrfs_set_header_level(split, btrfs_header_level(c));
+ btrfs_set_header_bytenr(split, split->start);
+ btrfs_set_header_generation(split, trans->transid);
+ btrfs_set_header_backref_rev(split, BTRFS_MIXED_BACKREF_REV);
+ btrfs_set_header_owner(split, root->root_key.objectid);
+ write_extent_buffer(split, root->fs_info->fsid,
+ btrfs_header_fsid(), BTRFS_FSID_SIZE);
+ write_extent_buffer(split, root->fs_info->chunk_tree_uuid,
+ btrfs_header_chunk_tree_uuid(split),
+ BTRFS_UUID_SIZE);
+
+
+ copy_extent_buffer(split, c,
+ btrfs_node_key_ptr_offset(0),
+ btrfs_node_key_ptr_offset(mid),
+ (c_nritems - mid) * sizeof(struct btrfs_key_ptr));
+ btrfs_set_header_nritems(split, c_nritems - mid);
+ btrfs_set_header_nritems(c, mid);
+ ret = 0;
+
+ btrfs_mark_buffer_dirty(c);
+ btrfs_mark_buffer_dirty(split);
+
+ wret = insert_ptr(trans, root, path, &disk_key, split->start,
+ path->slots[level + 1] + 1,
+ level + 1);
+ if (wret)
+ ret = wret;
+
+ if (path->slots[level] >= mid) {
+ path->slots[level] -= mid;
+ free_extent_buffer(c);
+ path->nodes[level] = split;
+ path->slots[level + 1] += 1;
+ } else {
+ free_extent_buffer(split);
}
- /* Now that the tree has room, insert the requested pointer */
- return __insert_ptr(root, path, key, blocknr, path->slots[level] + 1,
- level);
+ return ret;
}
/*
* and nr indicate which items in the leaf to check. This totals up the
* space used both by the item structs and the item data
*/
-int leaf_space_used(struct leaf *l, int start, int nr)
+static int leaf_space_used(struct extent_buffer *l, int start, int nr)
{
int data_len;
- int end = start + nr - 1;
+ int nritems = btrfs_header_nritems(l);
+ int end = min(nritems, start + nr) - 1;
if (!nr)
return 0;
- data_len = l->items[start].offset + l->items[start].size;
- data_len = data_len - l->items[end].offset;
- data_len += sizeof(struct item) * nr;
+ data_len = btrfs_item_end_nr(l, start);
+ data_len = data_len - btrfs_item_offset_nr(l, end);
+ data_len += sizeof(struct btrfs_item) * nr;
+ WARN_ON(data_len < 0);
return data_len;
}
/*
+ * The space between the end of the leaf items and
+ * the start of the leaf data. IOW, how much room
+ * the leaf has left for both items and data
+ */
+int btrfs_leaf_free_space(struct btrfs_root *root, struct extent_buffer *leaf)
+{
+ u32 nodesize = (root ? BTRFS_LEAF_DATA_SIZE(root->fs_info) : leaf->len);
+ int nritems = btrfs_header_nritems(leaf);
+ int ret;
+ ret = nodesize - leaf_space_used(leaf, 0, nritems);
+ if (ret < 0) {
+ printk("leaf free space ret %d, leaf data size %u, used %d nritems %d\n",
+ ret, nodesize, leaf_space_used(leaf, 0, nritems),
+ nritems);
+ }
+ return ret;
+}
+
+/*
+ * push some data in the path leaf to the right, trying to free up at
+ * least data_size bytes. returns zero if the push worked, nonzero otherwise
+ *
+ * returns 1 if the push failed because the other node didn't have enough
+ * room, 0 if everything worked out and < 0 if there were major errors.
+ */
+static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root
+ *root, struct btrfs_path *path, int data_size,
+ int empty)
+{
+ struct extent_buffer *left = path->nodes[0];
+ struct extent_buffer *right;
+ struct extent_buffer *upper;
+ struct btrfs_disk_key disk_key;
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ int slot;
+ u32 i;
+ int free_space;
+ int push_space = 0;
+ int push_items = 0;
+ struct btrfs_item *item;
+ u32 left_nritems;
+ u32 nr;
+ u32 right_nritems;
+ u32 data_end;
+ u32 this_item_size;
+ int ret;
+
+ slot = path->slots[1];
+ if (!path->nodes[1]) {
+ return 1;
+ }
+ upper = path->nodes[1];
+ if (slot >= btrfs_header_nritems(upper) - 1)
+ return 1;
+
+ right = read_node_slot(fs_info, upper, slot + 1);
+ if (!extent_buffer_uptodate(right)) {
+ if (IS_ERR(right))
+ return PTR_ERR(right);
+ return -EIO;
+ }
+ free_space = btrfs_leaf_free_space(root, right);
+ if (free_space < data_size) {
+ free_extent_buffer(right);
+ return 1;
+ }
+
+ /* cow and double check */
+ ret = btrfs_cow_block(trans, root, right, upper,
+ slot + 1, &right);
+ if (ret) {
+ free_extent_buffer(right);
+ return 1;
+ }
+ free_space = btrfs_leaf_free_space(root, right);
+ if (free_space < data_size) {
+ free_extent_buffer(right);
+ return 1;
+ }
+
+ left_nritems = btrfs_header_nritems(left);
+ if (left_nritems == 0) {
+ free_extent_buffer(right);
+ return 1;
+ }
+
+ if (empty)
+ nr = 0;
+ else
+ nr = 1;
+
+ i = left_nritems - 1;
+ while (i >= nr) {
+ item = btrfs_item_nr(i);
+
+ if (path->slots[0] == i)
+ push_space += data_size + sizeof(*item);
+
+ this_item_size = btrfs_item_size(left, item);
+ if (this_item_size + sizeof(*item) + push_space > free_space)
+ break;
+ push_items++;
+ push_space += this_item_size + sizeof(*item);
+ if (i == 0)
+ break;
+ i--;
+ }
+
+ if (push_items == 0) {
+ free_extent_buffer(right);
+ return 1;
+ }
+
+ if (!empty && push_items == left_nritems)
+ WARN_ON(1);
+
+ /* push left to right */
+ right_nritems = btrfs_header_nritems(right);
+
+ push_space = btrfs_item_end_nr(left, left_nritems - push_items);
+ push_space -= leaf_data_end(fs_info, left);
+
+ /* make room in the right data area */
+ data_end = leaf_data_end(fs_info, right);
+ memmove_extent_buffer(right,
+ btrfs_leaf_data(right) + data_end - push_space,
+ btrfs_leaf_data(right) + data_end,
+ BTRFS_LEAF_DATA_SIZE(root->fs_info) - data_end);
+
+ /* copy from the left data area */
+ copy_extent_buffer(right, left, btrfs_leaf_data(right) +
+ BTRFS_LEAF_DATA_SIZE(root->fs_info) - push_space,
+ btrfs_leaf_data(left) + leaf_data_end(fs_info, left),
+ push_space);
+
+ memmove_extent_buffer(right, btrfs_item_nr_offset(push_items),
+ btrfs_item_nr_offset(0),
+ right_nritems * sizeof(struct btrfs_item));
+
+ /* copy the items from left to right */
+ copy_extent_buffer(right, left, btrfs_item_nr_offset(0),
+ btrfs_item_nr_offset(left_nritems - push_items),
+ push_items * sizeof(struct btrfs_item));
+
+ /* update the item pointers */
+ right_nritems += push_items;
+ btrfs_set_header_nritems(right, right_nritems);
+ push_space = BTRFS_LEAF_DATA_SIZE(root->fs_info);
+ for (i = 0; i < right_nritems; i++) {
+ item = btrfs_item_nr(i);
+ push_space -= btrfs_item_size(right, item);
+ btrfs_set_item_offset(right, item, push_space);
+ }
+
+ left_nritems -= push_items;
+ btrfs_set_header_nritems(left, left_nritems);
+
+ if (left_nritems)
+ btrfs_mark_buffer_dirty(left);
+ btrfs_mark_buffer_dirty(right);
+
+ btrfs_item_key(right, &disk_key, 0);
+ btrfs_set_node_key(upper, &disk_key, slot + 1);
+ btrfs_mark_buffer_dirty(upper);
+
+ /* then fixup the leaf pointer in the path */
+ if (path->slots[0] >= left_nritems) {
+ path->slots[0] -= left_nritems;
+ free_extent_buffer(path->nodes[0]);
+ path->nodes[0] = right;
+ path->slots[1] += 1;
+ } else {
+ free_extent_buffer(right);
+ }
+ return 0;
+}
+/*
* push some data in the path leaf to the left, trying to free up at
* least data_size bytes. returns zero if the push worked, nonzero otherwise
*/
-int push_leaf_left(struct ctree_root *root, struct ctree_path *path,
- int data_size)
+static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root
+ *root, struct btrfs_path *path, int data_size,
+ int empty)
{
- struct tree_buffer *right_buf = path->nodes[0];
- struct leaf *right = &right_buf->leaf;
- struct tree_buffer *t;
- struct leaf *left;
+ struct btrfs_disk_key disk_key;
+ struct extent_buffer *right = path->nodes[0];
+ struct extent_buffer *left;
+ struct btrfs_fs_info *fs_info = root->fs_info;
int slot;
int i;
int free_space;
int push_space = 0;
int push_items = 0;
- struct item *item;
- int old_left_nritems;
+ struct btrfs_item *item;
+ u32 old_left_nritems;
+ u32 right_nritems;
+ u32 nr;
+ int ret = 0;
+ u32 this_item_size;
+ u32 old_left_item_size;
slot = path->slots[1];
- if (slot == 0) {
+ if (slot == 0)
+ return 1;
+ if (!path->nodes[1])
+ return 1;
+
+ right_nritems = btrfs_header_nritems(right);
+ if (right_nritems == 0) {
return 1;
}
- if (!path->nodes[1]) {
+
+ left = read_node_slot(fs_info, path->nodes[1], slot - 1);
+ free_space = btrfs_leaf_free_space(root, left);
+ if (free_space < data_size) {
+ free_extent_buffer(left);
return 1;
}
- t = read_tree_block(root, path->nodes[1]->node.blockptrs[slot - 1]);
- left = &t->leaf;
- free_space = leaf_free_space(left);
- if (free_space < data_size + sizeof(struct item)) {
- tree_block_release(root, t);
+
+ /* cow and double check */
+ ret = btrfs_cow_block(trans, root, left,
+ path->nodes[1], slot - 1, &left);
+ if (ret) {
+ /* we hit -ENOSPC, but it isn't fatal here */
+ free_extent_buffer(left);
return 1;
}
- for (i = 0; i < right->header.nritems; i++) {
- item = right->items + i;
+
+ free_space = btrfs_leaf_free_space(root, left);
+ if (free_space < data_size) {
+ free_extent_buffer(left);
+ return 1;
+ }
+
+ if (empty)
+ nr = right_nritems;
+ else
+ nr = right_nritems - 1;
+
+ for (i = 0; i < nr; i++) {
+ item = btrfs_item_nr(i);
+
if (path->slots[0] == i)
push_space += data_size + sizeof(*item);
- if (item->size + sizeof(*item) + push_space > free_space)
+
+ this_item_size = btrfs_item_size(right, item);
+ if (this_item_size + sizeof(*item) + push_space > free_space)
break;
+
push_items++;
- push_space += item->size + sizeof(*item);
+ push_space += this_item_size + sizeof(*item);
}
+
if (push_items == 0) {
- tree_block_release(root, t);
+ free_extent_buffer(left);
return 1;
}
+ if (!empty && push_items == btrfs_header_nritems(right))
+ WARN_ON(1);
+
/* push data from right to left */
- memcpy(left->items + left->header.nritems,
- right->items, push_items * sizeof(struct item));
- push_space = LEAF_DATA_SIZE - right->items[push_items -1].offset;
- memcpy(left->data + leaf_data_end(left) - push_space,
- right->data + right->items[push_items - 1].offset,
- push_space);
- old_left_nritems = left->header.nritems;
- BUG_ON(old_left_nritems < 0);
+ copy_extent_buffer(left, right,
+ btrfs_item_nr_offset(btrfs_header_nritems(left)),
+ btrfs_item_nr_offset(0),
+ push_items * sizeof(struct btrfs_item));
+
+ push_space = BTRFS_LEAF_DATA_SIZE(root->fs_info) -
+ btrfs_item_offset_nr(right, push_items -1);
+
+ copy_extent_buffer(left, right, btrfs_leaf_data(left) +
+ leaf_data_end(fs_info, left) - push_space,
+ btrfs_leaf_data(right) +
+ btrfs_item_offset_nr(right, push_items - 1),
+ push_space);
+ old_left_nritems = btrfs_header_nritems(left);
+ BUG_ON(old_left_nritems == 0);
+
+ old_left_item_size = btrfs_item_offset_nr(left, old_left_nritems - 1);
+ for (i = old_left_nritems; i < old_left_nritems + push_items; i++) {
+ u32 ioff;
+
+ item = btrfs_item_nr(i);
+ ioff = btrfs_item_offset(left, item);
+ btrfs_set_item_offset(left, item,
+ ioff - (BTRFS_LEAF_DATA_SIZE(root->fs_info) -
+ old_left_item_size));
+ }
+ btrfs_set_header_nritems(left, old_left_nritems + push_items);
+
+ /* fixup right node */
+ if (push_items > right_nritems) {
+ printk("push items %d nr %u\n", push_items, right_nritems);
+ WARN_ON(1);
+ }
+
+ if (push_items < right_nritems) {
+ push_space = btrfs_item_offset_nr(right, push_items - 1) -
+ leaf_data_end(fs_info, right);
+ memmove_extent_buffer(right, btrfs_leaf_data(right) +
+ BTRFS_LEAF_DATA_SIZE(root->fs_info) -
+ push_space,
+ btrfs_leaf_data(right) +
+ leaf_data_end(fs_info, right),
+ push_space);
+
+ memmove_extent_buffer(right, btrfs_item_nr_offset(0),
+ btrfs_item_nr_offset(push_items),
+ (btrfs_header_nritems(right) - push_items) *
+ sizeof(struct btrfs_item));
+ }
+ right_nritems -= push_items;
+ btrfs_set_header_nritems(right, right_nritems);
+ push_space = BTRFS_LEAF_DATA_SIZE(root->fs_info);
+ for (i = 0; i < right_nritems; i++) {
+ item = btrfs_item_nr(i);
+ push_space = push_space - btrfs_item_size(right, item);
+ btrfs_set_item_offset(right, item, push_space);
+ }
+
+ btrfs_mark_buffer_dirty(left);
+ if (right_nritems)
+ btrfs_mark_buffer_dirty(right);
+
+ btrfs_item_key(right, &disk_key, 0);
+ btrfs_fixup_low_keys(root, path, &disk_key, 1);
+
+ /* then fixup the leaf pointer in the path */
+ if (path->slots[0] < push_items) {
+ path->slots[0] += old_left_nritems;
+ free_extent_buffer(path->nodes[0]);
+ path->nodes[0] = left;
+ path->slots[1] -= 1;
+ } else {
+ free_extent_buffer(left);
+ path->slots[0] -= push_items;
+ }
+ BUG_ON(path->slots[0] < 0);
+ return ret;
+}
+
+/*
+ * split the path's leaf in two, making sure there is at least data_size
+ * available for the resulting leaf level of the path.
+ *
+ * returns 0 if all went well and < 0 on failure.
+ */
+static noinline int copy_for_split(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ struct extent_buffer *l,
+ struct extent_buffer *right,
+ int slot, int mid, int nritems)
+{
+ int data_copy_size;
+ int rt_data_off;
+ int i;
+ int ret = 0;
+ int wret;
+ struct btrfs_disk_key disk_key;
+
+ nritems = nritems - mid;
+ btrfs_set_header_nritems(right, nritems);
+ data_copy_size = btrfs_item_end_nr(l, mid) -
+ leaf_data_end(root->fs_info, l);
+
+ copy_extent_buffer(right, l, btrfs_item_nr_offset(0),
+ btrfs_item_nr_offset(mid),
+ nritems * sizeof(struct btrfs_item));
+
+ copy_extent_buffer(right, l,
+ btrfs_leaf_data(right) +
+ BTRFS_LEAF_DATA_SIZE(root->fs_info) -
+ data_copy_size, btrfs_leaf_data(l) +
+ leaf_data_end(root->fs_info, l), data_copy_size);
+
+ rt_data_off = BTRFS_LEAF_DATA_SIZE(root->fs_info) -
+ btrfs_item_end_nr(l, mid);
+
+ for (i = 0; i < nritems; i++) {
+ struct btrfs_item *item = btrfs_item_nr(i);
+ u32 ioff = btrfs_item_offset(right, item);
+ btrfs_set_item_offset(right, item, ioff + rt_data_off);
+ }
+
+ btrfs_set_header_nritems(l, mid);
+ ret = 0;
+ btrfs_item_key(right, &disk_key, 0);
+ wret = insert_ptr(trans, root, path, &disk_key, right->start,
+ path->slots[1] + 1, 1);
+ if (wret)
+ ret = wret;
+
+ btrfs_mark_buffer_dirty(right);
+ btrfs_mark_buffer_dirty(l);
+ BUG_ON(path->slots[0] != slot);
+
+ if (mid <= slot) {
+ free_extent_buffer(path->nodes[0]);
+ path->nodes[0] = right;
+ path->slots[0] -= mid;
+ path->slots[1] += 1;
+ } else {
+ free_extent_buffer(right);
+ }
+
+ BUG_ON(path->slots[0] < 0);
+
+ return ret;
+}
+
+/*
+ * split the path's leaf in two, making sure there is at least data_size
+ * available for the resulting leaf level of the path.
+ *
+ * returns 0 if all went well and < 0 on failure.
+ */
+static noinline int split_leaf(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_key *ins_key,
+ struct btrfs_path *path, int data_size,
+ int extend)
+{
+ struct btrfs_disk_key disk_key;
+ struct extent_buffer *l;
+ u32 nritems;
+ int mid;
+ int slot;
+ struct extent_buffer *right;
+ int ret = 0;
+ int wret;
+ int split;
+ int num_doubles = 0;
+
+ l = path->nodes[0];
+ slot = path->slots[0];
+ if (extend && data_size + btrfs_item_size_nr(l, slot) +
+ sizeof(struct btrfs_item) > BTRFS_LEAF_DATA_SIZE(root->fs_info))
+ return -EOVERFLOW;
+
+ /* first try to make some room by pushing left and right */
+ if (data_size && ins_key->type != BTRFS_DIR_ITEM_KEY) {
+ wret = push_leaf_right(trans, root, path, data_size, 0);
+ if (wret < 0)
+ return wret;
+ if (wret) {
+ wret = push_leaf_left(trans, root, path, data_size, 0);
+ if (wret < 0)
+ return wret;
+ }
+ l = path->nodes[0];
+
+ /* did the pushes work? */
+ if (btrfs_leaf_free_space(root, l) >= data_size)
+ return 0;
+ }
+
+ if (!path->nodes[1]) {
+ ret = insert_new_root(trans, root, path, 1);
+ if (ret)
+ return ret;
+ }
+again:
+ split = 1;
+ l = path->nodes[0];
+ slot = path->slots[0];
+ nritems = btrfs_header_nritems(l);
+ mid = (nritems + 1) / 2;
+
+ if (mid <= slot) {
+ if (nritems == 1 ||
+ leaf_space_used(l, mid, nritems - mid) + data_size >
+ BTRFS_LEAF_DATA_SIZE(root->fs_info)) {
+ if (slot >= nritems) {
+ split = 0;
+ } else {
+ mid = slot;
+ if (mid != nritems &&
+ leaf_space_used(l, mid, nritems - mid) +
+ data_size >
+ BTRFS_LEAF_DATA_SIZE(root->fs_info)) {
+ split = 2;
+ }
+ }
+ }
+ } else {
+ if (leaf_space_used(l, 0, mid) + data_size >
+ BTRFS_LEAF_DATA_SIZE(root->fs_info)) {
+ if (!extend && data_size && slot == 0) {
+ split = 0;
+ } else if ((extend || !data_size) && slot == 0) {
+ mid = 1;
+ } else {
+ mid = slot;
+ if (mid != nritems &&
+ leaf_space_used(l, mid, nritems - mid) +
+ data_size >
+ BTRFS_LEAF_DATA_SIZE(root->fs_info)) {
+ split = 2 ;
+ }
+ }
+ }
+ }
+
+ if (split == 0)
+ btrfs_cpu_key_to_disk(&disk_key, ins_key);
+ else
+ btrfs_item_key(l, &disk_key, mid);
+
+ right = btrfs_alloc_free_block(trans, root, root->fs_info->nodesize,
+ root->root_key.objectid,
+ &disk_key, 0, l->start, 0);
+ if (IS_ERR(right)) {
+ BUG_ON(1);
+ return PTR_ERR(right);
+ }
+
+ memset_extent_buffer(right, 0, 0, sizeof(struct btrfs_header));
+ btrfs_set_header_bytenr(right, right->start);
+ btrfs_set_header_generation(right, trans->transid);
+ btrfs_set_header_backref_rev(right, BTRFS_MIXED_BACKREF_REV);
+ btrfs_set_header_owner(right, root->root_key.objectid);
+ btrfs_set_header_level(right, 0);
+ write_extent_buffer(right, root->fs_info->fsid,
+ btrfs_header_fsid(), BTRFS_FSID_SIZE);
+
+ write_extent_buffer(right, root->fs_info->chunk_tree_uuid,
+ btrfs_header_chunk_tree_uuid(right),
+ BTRFS_UUID_SIZE);
+
+ if (split == 0) {
+ if (mid <= slot) {
+ btrfs_set_header_nritems(right, 0);
+ wret = insert_ptr(trans, root, path,
+ &disk_key, right->start,
+ path->slots[1] + 1, 1);
+ if (wret)
+ ret = wret;
+
+ free_extent_buffer(path->nodes[0]);
+ path->nodes[0] = right;
+ path->slots[0] = 0;
+ path->slots[1] += 1;
+ } else {
+ btrfs_set_header_nritems(right, 0);
+ wret = insert_ptr(trans, root, path,
+ &disk_key,
+ right->start,
+ path->slots[1], 1);
+ if (wret)
+ ret = wret;
+ free_extent_buffer(path->nodes[0]);
+ path->nodes[0] = right;
+ path->slots[0] = 0;
+ if (path->slots[1] == 0) {
+ btrfs_fixup_low_keys(root, path,
+ &disk_key, 1);
+ }
+ }
+ btrfs_mark_buffer_dirty(right);
+ return ret;
+ }
+
+ ret = copy_for_split(trans, root, path, l, right, slot, mid, nritems);
+ BUG_ON(ret);
+
+ if (split == 2) {
+ BUG_ON(num_doubles != 0);
+ num_doubles++;
+ goto again;
+ }
+
+ return ret;
+}
+
+/*
+ * This function splits a single item into two items,
+ * giving 'new_key' to the new item and splitting the
+ * old one at split_offset (from the start of the item).
+ *
+ * The path may be released by this operation. After
+ * the split, the path is pointing to the old item. The
+ * new item is going to be in the same node as the old one.
+ *
+ * Note, the item being split must be smaller enough to live alone on
+ * a tree block with room for one extra struct btrfs_item
+ *
+ * This allows us to split the item in place, keeping a lock on the
+ * leaf the entire time.
+ */
+int btrfs_split_item(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ struct btrfs_key *new_key,
+ unsigned long split_offset)
+{
+ u32 item_size;
+ struct extent_buffer *leaf;
+ struct btrfs_key orig_key;
+ struct btrfs_item *item;
+ struct btrfs_item *new_item;
+ int ret = 0;
+ int slot;
+ u32 nritems;
+ u32 orig_offset;
+ struct btrfs_disk_key disk_key;
+ char *buf;
+
+ leaf = path->nodes[0];
+ btrfs_item_key_to_cpu(leaf, &orig_key, path->slots[0]);
+ if (btrfs_leaf_free_space(root, leaf) >= sizeof(struct btrfs_item))
+ goto split;
+
+ item_size = btrfs_item_size_nr(leaf, path->slots[0]);
+ btrfs_release_path(path);
+
+ path->search_for_split = 1;
+
+ ret = btrfs_search_slot(trans, root, &orig_key, path, 0, 1);
+ path->search_for_split = 0;
+
+ /* if our item isn't there or got smaller, return now */
+ if (ret != 0 || item_size != btrfs_item_size_nr(path->nodes[0],
+ path->slots[0])) {
+ return -EAGAIN;
+ }
+
+ ret = split_leaf(trans, root, &orig_key, path, 0, 0);
+ BUG_ON(ret);
+
+ BUG_ON(btrfs_leaf_free_space(root, leaf) < sizeof(struct btrfs_item));
+ leaf = path->nodes[0];
+
+split:
+ item = btrfs_item_nr(path->slots[0]);
+ orig_offset = btrfs_item_offset(leaf, item);
+ item_size = btrfs_item_size(leaf, item);
+
+
+ buf = kmalloc(item_size, GFP_NOFS);
+ BUG_ON(!buf);
+ read_extent_buffer(leaf, buf, btrfs_item_ptr_offset(leaf,
+ path->slots[0]), item_size);
+ slot = path->slots[0] + 1;
+ leaf = path->nodes[0];
+
+ nritems = btrfs_header_nritems(leaf);
+
+ if (slot < nritems) {
+ /* shift the items */
+ memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot + 1),
+ btrfs_item_nr_offset(slot),
+ (nritems - slot) * sizeof(struct btrfs_item));
+
+ }
+
+ btrfs_cpu_key_to_disk(&disk_key, new_key);
+ btrfs_set_item_key(leaf, &disk_key, slot);
+
+ new_item = btrfs_item_nr(slot);
- for(i = old_left_nritems; i < old_left_nritems + push_items; i++) {
- left->items[i].offset -= LEAF_DATA_SIZE -
- left->items[old_left_nritems -1].offset;
- }
- left->header.nritems += push_items;
+ btrfs_set_item_offset(leaf, new_item, orig_offset);
+ btrfs_set_item_size(leaf, new_item, item_size - split_offset);
- /* fixup right node */
- push_space = right->items[push_items-1].offset - leaf_data_end(right);
- memmove(right->data + LEAF_DATA_SIZE - push_space, right->data +
- leaf_data_end(right), push_space);
- memmove(right->items, right->items + push_items,
- (right->header.nritems - push_items) * sizeof(struct item));
- right->header.nritems -= push_items;
- push_space = LEAF_DATA_SIZE;
+ btrfs_set_item_offset(leaf, item,
+ orig_offset + item_size - split_offset);
+ btrfs_set_item_size(leaf, item, split_offset);
+
+ btrfs_set_header_nritems(leaf, nritems + 1);
+
+ /* write the data for the start of the original item */
+ write_extent_buffer(leaf, buf,
+ btrfs_item_ptr_offset(leaf, path->slots[0]),
+ split_offset);
- for (i = 0; i < right->header.nritems; i++) {
- right->items[i].offset = push_space - right->items[i].size;
- push_space = right->items[i].offset;
+ /* write the data for the new item */
+ write_extent_buffer(leaf, buf + split_offset,
+ btrfs_item_ptr_offset(leaf, slot),
+ item_size - split_offset);
+ btrfs_mark_buffer_dirty(leaf);
+
+ ret = 0;
+ if (btrfs_leaf_free_space(root, leaf) < 0) {
+ btrfs_print_leaf(root, leaf);
+ BUG();
}
+ kfree(buf);
+ return ret;
+}
- write_tree_block(root, t);
- write_tree_block(root, right_buf);
+int btrfs_truncate_item(struct btrfs_root *root, struct btrfs_path *path,
+ u32 new_size, int from_end)
+{
+ int ret = 0;
+ int slot;
+ struct extent_buffer *leaf;
+ struct btrfs_item *item;
+ u32 nritems;
+ unsigned int data_end;
+ unsigned int old_data_start;
+ unsigned int old_size;
+ unsigned int size_diff;
+ int i;
- fixup_low_keys(root, path, &right->items[0].key, 1);
+ leaf = path->nodes[0];
+ slot = path->slots[0];
- /* then fixup the leaf pointer in the path */
- if (path->slots[0] < push_items) {
- path->slots[0] += old_left_nritems;
- tree_block_release(root, path->nodes[0]);
- path->nodes[0] = t;
- path->slots[1] -= 1;
+ old_size = btrfs_item_size_nr(leaf, slot);
+ if (old_size == new_size)
+ return 0;
+
+ nritems = btrfs_header_nritems(leaf);
+ data_end = leaf_data_end(root->fs_info, leaf);
+
+ old_data_start = btrfs_item_offset_nr(leaf, slot);
+
+ size_diff = old_size - new_size;
+
+ BUG_ON(slot < 0);
+ BUG_ON(slot >= nritems);
+
+ /*
+ * item0..itemN ... dataN.offset..dataN.size .. data0.size
+ */
+ /* first correct the data pointers */
+ for (i = slot; i < nritems; i++) {
+ u32 ioff;
+ item = btrfs_item_nr(i);
+ ioff = btrfs_item_offset(leaf, item);
+ btrfs_set_item_offset(leaf, item, ioff + size_diff);
+ }
+
+ /* shift the data */
+ if (from_end) {
+ memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) +
+ data_end + size_diff, btrfs_leaf_data(leaf) +
+ data_end, old_data_start + new_size - data_end);
} else {
- tree_block_release(root, t);
- path->slots[0] -= push_items;
+ struct btrfs_disk_key disk_key;
+ u64 offset;
+
+ btrfs_item_key(leaf, &disk_key, slot);
+
+ if (btrfs_disk_key_type(&disk_key) == BTRFS_EXTENT_DATA_KEY) {
+ unsigned long ptr;
+ struct btrfs_file_extent_item *fi;
+
+ fi = btrfs_item_ptr(leaf, slot,
+ struct btrfs_file_extent_item);
+ fi = (struct btrfs_file_extent_item *)(
+ (unsigned long)fi - size_diff);
+
+ if (btrfs_file_extent_type(leaf, fi) ==
+ BTRFS_FILE_EXTENT_INLINE) {
+ ptr = btrfs_item_ptr_offset(leaf, slot);
+ memmove_extent_buffer(leaf, ptr,
+ (unsigned long)fi,
+ offsetof(struct btrfs_file_extent_item,
+ disk_bytenr));
+ }
+ }
+
+ memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) +
+ data_end + size_diff, btrfs_leaf_data(leaf) +
+ data_end, old_data_start - data_end);
+
+ offset = btrfs_disk_key_offset(&disk_key);
+ btrfs_set_disk_key_offset(&disk_key, offset + size_diff);
+ btrfs_set_item_key(leaf, &disk_key, slot);
+ if (slot == 0)
+ btrfs_fixup_low_keys(root, path, &disk_key, 1);
}
- BUG_ON(path->slots[0] < 0);
- return 0;
+
+ item = btrfs_item_nr(slot);
+ btrfs_set_item_size(leaf, item, new_size);
+ btrfs_mark_buffer_dirty(leaf);
+
+ ret = 0;
+ if (btrfs_leaf_free_space(root, leaf) < 0) {
+ btrfs_print_leaf(root, leaf);
+ BUG();
+ }
+ return ret;
}
-/*
- * split the path's leaf in two, making sure there is at least data_size
- * available for the resulting leaf level of the path.
- */
-int split_leaf(struct ctree_root *root, struct ctree_path *path, int data_size)
+int btrfs_extend_item(struct btrfs_root *root, struct btrfs_path *path,
+ u32 data_size)
{
- struct tree_buffer *l_buf = path->nodes[0];
- struct leaf *l = &l_buf->leaf;
- int nritems;
- int mid;
+ int ret = 0;
int slot;
- struct leaf *right;
- struct tree_buffer *right_buffer;
- int space_needed = data_size + sizeof(struct item);
- int data_copy_size;
- int rt_data_off;
+ struct extent_buffer *leaf;
+ struct btrfs_item *item;
+ u32 nritems;
+ unsigned int data_end;
+ unsigned int old_data;
+ unsigned int old_size;
int i;
- int ret;
- if (push_leaf_left(root, path, data_size) == 0) {
- l_buf = path->nodes[0];
- l = &l_buf->leaf;
- if (leaf_free_space(l) >= sizeof(struct item) + data_size)
- return 0;
+ leaf = path->nodes[0];
+
+ nritems = btrfs_header_nritems(leaf);
+ data_end = leaf_data_end(root->fs_info, leaf);
+
+ if (btrfs_leaf_free_space(root, leaf) < data_size) {
+ btrfs_print_leaf(root, leaf);
+ BUG();
}
slot = path->slots[0];
- nritems = l->header.nritems;
- mid = (nritems + 1)/ 2;
-
- right_buffer = alloc_free_block(root);
- BUG_ON(!right_buffer);
- BUG_ON(mid == nritems);
- right = &right_buffer->leaf;
- memset(right, 0, sizeof(*right));
- if (mid <= slot) {
- if (leaf_space_used(l, mid, nritems - mid) + space_needed >
- LEAF_DATA_SIZE)
- BUG();
- } else {
- if (leaf_space_used(l, 0, mid + 1) + space_needed >
- LEAF_DATA_SIZE)
- BUG();
- }
- right->header.nritems = nritems - mid;
- right->header.blocknr = right_buffer->blocknr;
- right->header.flags = node_level(0);
- right->header.parentid = root->node->node.header.parentid;
- data_copy_size = l->items[mid].offset + l->items[mid].size -
- leaf_data_end(l);
- memcpy(right->items, l->items + mid,
- (nritems - mid) * sizeof(struct item));
- memcpy(right->data + LEAF_DATA_SIZE - data_copy_size,
- l->data + leaf_data_end(l), data_copy_size);
- rt_data_off = LEAF_DATA_SIZE -
- (l->items[mid].offset + l->items[mid].size);
-
- for (i = 0; i < right->header.nritems; i++)
- right->items[i].offset += rt_data_off;
-
- l->header.nritems = mid;
- ret = insert_ptr(root, path, &right->items[0].key,
- right_buffer->blocknr, 1);
-
- write_tree_block(root, right_buffer);
- write_tree_block(root, l_buf);
+ old_data = btrfs_item_end_nr(leaf, slot);
- BUG_ON(path->slots[0] != slot);
- if (mid <= slot) {
- tree_block_release(root, path->nodes[0]);
- path->nodes[0] = right_buffer;
- path->slots[0] -= mid;
- path->slots[1] += 1;
- } else
- tree_block_release(root, right_buffer);
- BUG_ON(path->slots[0] < 0);
+ BUG_ON(slot < 0);
+ if (slot >= nritems) {
+ btrfs_print_leaf(root, leaf);
+ printk("slot %d too large, nritems %d\n", slot, nritems);
+ BUG_ON(1);
+ }
+
+ /*
+ * item0..itemN ... dataN.offset..dataN.size .. data0.size
+ */
+ /* first correct the data pointers */
+ for (i = slot; i < nritems; i++) {
+ u32 ioff;
+ item = btrfs_item_nr(i);
+ ioff = btrfs_item_offset(leaf, item);
+ btrfs_set_item_offset(leaf, item, ioff - data_size);
+ }
+
+ /* shift the data */
+ memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) +
+ data_end - data_size, btrfs_leaf_data(leaf) +
+ data_end, old_data - data_end);
+
+ data_end = old_data;
+ old_size = btrfs_item_size_nr(leaf, slot);
+ item = btrfs_item_nr(slot);
+ btrfs_set_item_size(leaf, item, old_size + data_size);
+ btrfs_mark_buffer_dirty(leaf);
+
+ ret = 0;
+ if (btrfs_leaf_free_space(root, leaf) < 0) {
+ btrfs_print_leaf(root, leaf);
+ BUG();
+ }
return ret;
}
* Given a key and some data, insert an item into the tree.
* This does all the path init required, making room in the tree if needed.
*/
-int insert_item(struct ctree_root *root, struct key *key,
- void *data, int data_size)
+int btrfs_insert_empty_items(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ struct btrfs_key *cpu_key, u32 *data_size,
+ int nr)
{
- int ret;
+ struct extent_buffer *leaf;
+ struct btrfs_item *item;
+ int ret = 0;
int slot;
- int slot_orig;
- struct leaf *leaf;
- struct tree_buffer *leaf_buf;
- unsigned int nritems;
+ int i;
+ u32 nritems;
+ u32 total_size = 0;
+ u32 total_data = 0;
unsigned int data_end;
- struct ctree_path path;
+ struct btrfs_disk_key disk_key;
- refill_alloc_extent(root);
+ for (i = 0; i < nr; i++) {
+ total_data += data_size[i];
+ }
/* create a root if there isn't one */
- if (!root->node) {
+ if (!root->node)
BUG();
-#if 0
- struct tree_buffer *t;
- t = alloc_free_block(root);
- BUG_ON(!t);
- t->node.header.nritems = 0;
- t->node.header.flags = node_level(0);
- t->node.header.blocknr = t->blocknr;
- root->node = t;
- write_tree_block(root, t);
-#endif
- }
- init_path(&path);
- ret = search_slot(root, key, &path);
+
+ total_size = total_data + nr * sizeof(struct btrfs_item);
+ ret = btrfs_search_slot(trans, root, cpu_key, path, total_size, 1);
if (ret == 0) {
- release_path(root, &path);
return -EEXIST;
}
+ if (ret < 0)
+ goto out;
- slot_orig = path.slots[0];
- leaf_buf = path.nodes[0];
- leaf = &leaf_buf->leaf;
+ leaf = path->nodes[0];
- /* make room if needed */
- if (leaf_free_space(leaf) < sizeof(struct item) + data_size) {
- split_leaf(root, &path, data_size);
- leaf_buf = path.nodes[0];
- leaf = &path.nodes[0]->leaf;
- }
- nritems = leaf->header.nritems;
- data_end = leaf_data_end(leaf);
+ nritems = btrfs_header_nritems(leaf);
+ data_end = leaf_data_end(root->fs_info, leaf);
- if (leaf_free_space(leaf) < sizeof(struct item) + data_size)
+ if (btrfs_leaf_free_space(root, leaf) < total_size) {
+ btrfs_print_leaf(root, leaf);
+ printk("not enough freespace need %u have %d\n",
+ total_size, btrfs_leaf_free_space(root, leaf));
BUG();
+ }
- slot = path.slots[0];
+ slot = path->slots[0];
BUG_ON(slot < 0);
- if (slot == 0)
- fixup_low_keys(root, &path, key, 1);
- if (slot != nritems) {
- int i;
- unsigned int old_data = leaf->items[slot].offset +
- leaf->items[slot].size;
+ if (slot < nritems) {
+ unsigned int old_data = btrfs_item_end_nr(leaf, slot);
+
+ if (old_data < data_end) {
+ btrfs_print_leaf(root, leaf);
+ printk("slot %d old_data %d data_end %d\n",
+ slot, old_data, data_end);
+ BUG_ON(1);
+ }
/*
* item0..itemN ... dataN.offset..dataN.size .. data0.size
*/
/* first correct the data pointers */
- for (i = slot; i < nritems; i++)
- leaf->items[i].offset -= data_size;
+ for (i = slot; i < nritems; i++) {
+ u32 ioff;
+
+ item = btrfs_item_nr(i);
+ ioff = btrfs_item_offset(leaf, item);
+ btrfs_set_item_offset(leaf, item, ioff - total_data);
+ }
/* shift the items */
- memmove(leaf->items + slot + 1, leaf->items + slot,
- (nritems - slot) * sizeof(struct item));
+ memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot + nr),
+ btrfs_item_nr_offset(slot),
+ (nritems - slot) * sizeof(struct btrfs_item));
/* shift the data */
- memmove(leaf->data + data_end - data_size, leaf->data +
- data_end, old_data - data_end);
+ memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) +
+ data_end - total_data, btrfs_leaf_data(leaf) +
+ data_end, old_data - data_end);
data_end = old_data;
}
- /* copy the new data in */
- memcpy(&leaf->items[slot].key, key, sizeof(struct key));
- leaf->items[slot].offset = data_end - data_size;
- leaf->items[slot].size = data_size;
- memcpy(leaf->data + data_end - data_size, data, data_size);
- leaf->header.nritems += 1;
- write_tree_block(root, leaf_buf);
- if (leaf_free_space(leaf) < 0)
+
+ /* setup the item for the new data */
+ for (i = 0; i < nr; i++) {
+ btrfs_cpu_key_to_disk(&disk_key, cpu_key + i);
+ btrfs_set_item_key(leaf, &disk_key, slot + i);
+ item = btrfs_item_nr(slot + i);
+ btrfs_set_item_offset(leaf, item, data_end - data_size[i]);
+ data_end -= data_size[i];
+ btrfs_set_item_size(leaf, item, data_size[i]);
+ }
+ btrfs_set_header_nritems(leaf, nritems + nr);
+ btrfs_mark_buffer_dirty(leaf);
+
+ ret = 0;
+ if (slot == 0) {
+ btrfs_cpu_key_to_disk(&disk_key, cpu_key);
+ btrfs_fixup_low_keys(root, path, &disk_key, 1);
+ }
+
+ if (btrfs_leaf_free_space(root, leaf) < 0) {
+ btrfs_print_leaf(root, leaf);
BUG();
- release_path(root, &path);
- return 0;
+ }
+
+out:
+ return ret;
+}
+
+/*
+ * Given a key and some data, insert an item into the tree.
+ * This does all the path init required, making room in the tree if needed.
+ */
+int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root
+ *root, struct btrfs_key *cpu_key, void *data, u32
+ data_size)
+{
+ int ret = 0;
+ struct btrfs_path *path;
+ struct extent_buffer *leaf;
+ unsigned long ptr;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ ret = btrfs_insert_empty_item(trans, root, path, cpu_key, data_size);
+ if (!ret) {
+ leaf = path->nodes[0];
+ ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
+ write_extent_buffer(leaf, data, ptr, data_size);
+ btrfs_mark_buffer_dirty(leaf);
+ }
+ btrfs_free_path(path);
+ return ret;
}
/*
- * delete the pointer from a given level in the path. The path is not
- * fixed up, so after calling this it is not valid at that level.
+ * delete the pointer from a given node.
*
* If the delete empties a node, the node is removed from the tree,
* continuing all the way the root if required. The root is converted into
* a leaf if all the nodes are emptied.
*/
-int del_ptr(struct ctree_root *root, struct ctree_path *path, int level)
+int btrfs_del_ptr(struct btrfs_root *root, struct btrfs_path *path,
+ int level, int slot)
{
- int slot;
- struct tree_buffer *t;
- struct node *node;
- int nritems;
+ struct extent_buffer *parent = path->nodes[level];
+ u32 nritems;
+ int ret = 0;
- while(1) {
- t = path->nodes[level];
- if (!t)
- break;
- node = &t->node;
- slot = path->slots[level];
- nritems = node->header.nritems;
-
- if (slot != nritems -1) {
- memmove(node->keys + slot, node->keys + slot + 1,
- sizeof(struct key) * (nritems - slot - 1));
- memmove(node->blockptrs + slot,
- node->blockptrs + slot + 1,
- sizeof(u64) * (nritems - slot - 1));
- }
- node->header.nritems--;
- write_tree_block(root, t);
- if (node->header.nritems != 0) {
- int tslot;
- if (slot == 0)
- fixup_low_keys(root, path, node->keys,
- level + 1);
- tslot = path->slots[level+1];
- t->count++;
- push_node_left(root, path, level);
- if (node->header.nritems) {
- push_node_right(root, path, level);
- }
- if (node->header.nritems) {
- tree_block_release(root, t);
- break;
- }
- tree_block_release(root, t);
- path->slots[level+1] = tslot;
- }
- if (t == root->node) {
- /* just turn the root into a leaf and break */
- root->node->node.header.flags = node_level(0);
- write_tree_block(root, t);
- break;
- }
- level++;
- if (!path->nodes[level])
- BUG();
+ nritems = btrfs_header_nritems(parent);
+ if (slot < nritems - 1) {
+ /* shift the items */
+ memmove_extent_buffer(parent,
+ btrfs_node_key_ptr_offset(slot),
+ btrfs_node_key_ptr_offset(slot + 1),
+ sizeof(struct btrfs_key_ptr) *
+ (nritems - slot - 1));
}
- return 0;
+ nritems--;
+ btrfs_set_header_nritems(parent, nritems);
+ if (nritems == 0 && parent == root->node) {
+ BUG_ON(btrfs_header_level(root->node) != 1);
+ /* just turn the root into a leaf and break */
+ btrfs_set_header_level(root->node, 0);
+ } else if (slot == 0) {
+ struct btrfs_disk_key disk_key;
+
+ btrfs_node_key(parent, &disk_key, 0);
+ btrfs_fixup_low_keys(root, path, &disk_key, level + 1);
+ }
+ btrfs_mark_buffer_dirty(parent);
+ return ret;
+}
+
+/*
+ * a helper function to delete the leaf pointed to by path->slots[1] and
+ * path->nodes[1].
+ *
+ * This deletes the pointer in path->nodes[1] and frees the leaf
+ * block extent. zero is returned if it all worked out, < 0 otherwise.
+ *
+ * The path must have already been setup for deleting the leaf, including
+ * all the proper balancing. path->nodes[1] must be locked.
+ */
+static noinline int btrfs_del_leaf(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ struct extent_buffer *leaf)
+{
+ int ret;
+
+ WARN_ON(btrfs_header_generation(leaf) != trans->transid);
+ ret = btrfs_del_ptr(root, path, 1, path->slots[1]);
+ if (ret)
+ return ret;
+
+ ret = btrfs_free_extent(trans, root, leaf->start, leaf->len,
+ 0, root->root_key.objectid, 0, 0);
+ return ret;
}
/*
* delete the item at the leaf level in path. If that empties
* the leaf, remove it from the tree
*/
-int del_item(struct ctree_root *root, struct ctree_path *path)
+int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root,
+ struct btrfs_path *path, int slot, int nr)
{
- int slot;
- struct leaf *leaf;
- struct tree_buffer *leaf_buf;
- int doff;
- int dsize;
+ struct extent_buffer *leaf;
+ struct btrfs_item *item;
+ int last_off;
+ int dsize = 0;
+ int ret = 0;
+ int wret;
+ int i;
+ u32 nritems;
+
+ leaf = path->nodes[0];
+ last_off = btrfs_item_offset_nr(leaf, slot + nr - 1);
+
+ for (i = 0; i < nr; i++)
+ dsize += btrfs_item_size_nr(leaf, slot + i);
+
+ nritems = btrfs_header_nritems(leaf);
+
+ if (slot + nr != nritems) {
+ int data_end = leaf_data_end(root->fs_info, leaf);
+
+ memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) +
+ data_end + dsize,
+ btrfs_leaf_data(leaf) + data_end,
+ last_off - data_end);
+
+ for (i = slot + nr; i < nritems; i++) {
+ u32 ioff;
+
+ item = btrfs_item_nr(i);
+ ioff = btrfs_item_offset(leaf, item);
+ btrfs_set_item_offset(leaf, item, ioff + dsize);
+ }
+
+ memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot),
+ btrfs_item_nr_offset(slot + nr),
+ sizeof(struct btrfs_item) *
+ (nritems - slot - nr));
+ }
+ btrfs_set_header_nritems(leaf, nritems - nr);
+ nritems -= nr;
- leaf_buf = path->nodes[0];
- leaf = &leaf_buf->leaf;
- slot = path->slots[0];
- doff = leaf->items[slot].offset;
- dsize = leaf->items[slot].size;
-
- if (slot != leaf->header.nritems - 1) {
- int i;
- int data_end = leaf_data_end(leaf);
- memmove(leaf->data + data_end + dsize,
- leaf->data + data_end,
- doff - data_end);
- for (i = slot + 1; i < leaf->header.nritems; i++)
- leaf->items[i].offset += dsize;
- memmove(leaf->items + slot, leaf->items + slot + 1,
- sizeof(struct item) *
- (leaf->header.nritems - slot - 1));
- }
- leaf->header.nritems -= 1;
/* delete the leaf if we've emptied it */
- if (leaf->header.nritems == 0) {
- if (leaf_buf == root->node) {
- leaf->header.flags = node_level(0);
- write_tree_block(root, leaf_buf);
- } else
- del_ptr(root, path, 1);
+ if (nritems == 0) {
+ if (leaf == root->node) {
+ btrfs_set_header_level(leaf, 0);
+ } else {
+ clean_tree_block(trans, root, leaf);
+ wret = btrfs_del_leaf(trans, root, path, leaf);
+ BUG_ON(ret);
+ if (wret)
+ ret = wret;
+ }
} else {
- if (slot == 0)
- fixup_low_keys(root, path, &leaf->items[0].key, 1);
- write_tree_block(root, leaf_buf);
+ int used = leaf_space_used(leaf, 0, nritems);
+ if (slot == 0) {
+ struct btrfs_disk_key disk_key;
+
+ btrfs_item_key(leaf, &disk_key, 0);
+ btrfs_fixup_low_keys(root, path, &disk_key, 1);
+ }
+
/* delete the leaf if it is mostly empty */
- if (leaf_space_used(leaf, 0, leaf->header.nritems) <
- LEAF_DATA_SIZE / 4) {
+ if (used < BTRFS_LEAF_DATA_SIZE(root->fs_info) / 4) {
/* push_leaf_left fixes the path.
* make sure the path still points to our leaf
* for possible call to del_ptr below
*/
slot = path->slots[1];
- leaf_buf->count++;
- push_leaf_left(root, path, 1);
- if (leaf->header.nritems == 0) {
+ extent_buffer_get(leaf);
+
+ wret = push_leaf_left(trans, root, path, 1, 1);
+ if (wret < 0 && wret != -ENOSPC)
+ ret = wret;
+
+ if (path->nodes[0] == leaf &&
+ btrfs_header_nritems(leaf)) {
+ wret = push_leaf_right(trans, root, path, 1, 1);
+ if (wret < 0 && wret != -ENOSPC)
+ ret = wret;
+ }
+
+ if (btrfs_header_nritems(leaf) == 0) {
+ clean_tree_block(trans, root, leaf);
path->slots[1] = slot;
- del_ptr(root, path, 1);
+ ret = btrfs_del_leaf(trans, root, path, leaf);
+ BUG_ON(ret);
+ free_extent_buffer(leaf);
+
+ } else {
+ btrfs_mark_buffer_dirty(leaf);
+ free_extent_buffer(leaf);
}
- tree_block_release(root, leaf_buf);
+ } else {
+ btrfs_mark_buffer_dirty(leaf);
}
}
- return 0;
+ return ret;
}
-int next_leaf(struct ctree_root *root, struct ctree_path *path)
+/*
+ * walk up the tree as far as required to find the previous leaf.
+ * returns 0 if it found something or 1 if there are no lesser leaves.
+ * returns < 0 on io errors.
+ */
+int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path)
{
int slot;
int level = 1;
- u64 blocknr;
- struct tree_buffer *c;
- struct tree_buffer *next = NULL;
+ struct extent_buffer *c;
+ struct extent_buffer *next = NULL;
+ struct btrfs_fs_info *fs_info = root->fs_info;
- while(level < MAX_LEVEL) {
+ while(level < BTRFS_MAX_LEVEL) {
if (!path->nodes[level])
- return -1;
- slot = path->slots[level] + 1;
+ return 1;
+
+ slot = path->slots[level];
c = path->nodes[level];
- if (slot >= c->node.header.nritems) {
+ if (slot == 0) {
level++;
+ if (level == BTRFS_MAX_LEVEL)
+ return 1;
continue;
}
- blocknr = c->node.blockptrs[slot];
- if (next)
- tree_block_release(root, next);
- next = read_tree_block(root, blocknr);
+ slot--;
+
+ next = read_node_slot(fs_info, c, slot);
+ if (!extent_buffer_uptodate(next)) {
+ if (IS_ERR(next))
+ return PTR_ERR(next);
+ return -EIO;
+ }
break;
}
path->slots[level] = slot;
while(1) {
level--;
c = path->nodes[level];
- tree_block_release(root, c);
+ free_extent_buffer(c);
+ slot = btrfs_header_nritems(next);
+ if (slot != 0)
+ slot--;
path->nodes[level] = next;
- path->slots[level] = 0;
+ path->slots[level] = slot;
if (!level)
break;
- next = read_tree_block(root, next->node.blockptrs[0]);
+ next = read_node_slot(fs_info, next, slot);
+ if (!extent_buffer_uptodate(next)) {
+ if (IS_ERR(next))
+ return PTR_ERR(next);
+ return -EIO;
+ }
}
return 0;
}
-int alloc_extent(struct ctree_root *orig_root, u64 num_blocks, u64 search_start,
- u64 search_end, u64 owner, struct key *ins)
+/*
+ * walk up the tree as far as required to find the next leaf.
+ * returns 0 if it found something or 1 if there are no greater leaves.
+ * returns < 0 on io errors.
+ */
+int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)
{
- struct ctree_path path;
- struct key *key;
- int ret;
- u64 hole_size = 0;
- int slot = 0;
- u64 last_block;
- int start_found = 0;
- struct leaf *l;
- struct extent_item extent_item;
- struct ctree_root * root = orig_root->extent_root;
-
- init_path(&path);
- ins->objectid = search_start;
- ins->offset = 0;
- ins->flags = 0;
-
- ret = search_slot(root, ins, &path);
- while (1) {
- l = &path.nodes[0]->leaf;
- slot = path.slots[0];
- if (!l) {
- // FIXME allocate root
- }
- if (slot >= l->header.nritems) {
- ret = next_leaf(root, &path);
- if (ret == 0)
- continue;
- if (!start_found) {
- ins->objectid = search_start;
- ins->offset = num_blocks;
- hole_size = search_end - search_start;
- goto insert;
- }
- ins->objectid = last_block;
- ins->offset = num_blocks;
- hole_size = search_end - last_block;
- goto insert;
+ int slot;
+ int level = 1;
+ struct extent_buffer *c;
+ struct extent_buffer *next = NULL;
+ struct btrfs_fs_info *fs_info = root->fs_info;
+
+ while(level < BTRFS_MAX_LEVEL) {
+ if (!path->nodes[level])
+ return 1;
+
+ slot = path->slots[level] + 1;
+ c = path->nodes[level];
+ if (slot >= btrfs_header_nritems(c)) {
+ level++;
+ if (level == BTRFS_MAX_LEVEL)
+ return 1;
+ continue;
}
- key = &l->items[slot].key;
- if (start_found) {
- hole_size = key->objectid - last_block;
- if (hole_size > num_blocks) {
- ins->objectid = last_block;
- ins->offset = num_blocks;
- goto insert;
- }
- } else
- start_found = 1;
- last_block = key->objectid + key->offset;
- path.slots[0]++;
- }
- // FIXME -ENOSPC
-insert:
- release_path(root, &path);
- extent_item.refs = 1;
- extent_item.owner = owner;
- if (root == orig_root && root->reserve_extent->num_blocks == 0) {
- root->reserve_extent->blocknr = ins->objectid;
- root->reserve_extent->num_blocks = ins->offset;
- root->reserve_extent->num_used = 0;
- }
- ret = insert_item(root->extent_root, ins, &extent_item, sizeof(extent_item));
- return ret;
+
+ if (path->reada)
+ reada_for_search(root, path, level, slot, 0);
+
+ next = read_node_slot(fs_info, c, slot);
+ if (!extent_buffer_uptodate(next))
+ return -EIO;
+ break;
+ }
+ path->slots[level] = slot;
+ while(1) {
+ level--;
+ c = path->nodes[level];
+ free_extent_buffer(c);
+ path->nodes[level] = next;
+ path->slots[level] = 0;
+ if (!level)
+ break;
+ if (path->reada)
+ reada_for_search(root, path, level, 0, 0);
+ next = read_node_slot(fs_info, next, 0);
+ if (!extent_buffer_uptodate(next))
+ return -EIO;
+ }
+ return 0;
}
-static int refill_alloc_extent(struct ctree_root *root)
+int btrfs_previous_item(struct btrfs_root *root,
+ struct btrfs_path *path, u64 min_objectid,
+ int type)
{
- struct alloc_extent *ae = root->alloc_extent;
- struct key key;
+ struct btrfs_key found_key;
+ struct extent_buffer *leaf;
+ u32 nritems;
int ret;
- int min_blocks = MAX_LEVEL * 2;
- if (ae->num_blocks > ae->num_used && ae->num_blocks - ae->num_used >
- min_blocks)
- return 0;
- ae = root->reserve_extent;
- if (ae->num_blocks > ae->num_used) {
- if (root->alloc_extent->num_blocks == 0) {
- /* we should swap reserve/alloc_extent when alloc
- * fills up
- */
- BUG();
+ while(1) {
+ if (path->slots[0] == 0) {
+ ret = btrfs_prev_leaf(root, path);
+ if (ret != 0)
+ return ret;
+ } else {
+ path->slots[0]--;
}
- if (ae->num_blocks - ae->num_used < min_blocks)
- BUG();
- return 0;
+ leaf = path->nodes[0];
+ nritems = btrfs_header_nritems(leaf);
+ if (nritems == 0)
+ return 1;
+ if (path->slots[0] == nritems)
+ path->slots[0]--;
+
+ btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
+ if (found_key.objectid < min_objectid)
+ break;
+ if (found_key.type == type)
+ return 0;
+ if (found_key.objectid == min_objectid &&
+ found_key.type < type)
+ break;
}
- ret = alloc_extent(root,
- min_blocks * 2, 0, (unsigned long)-1,
- root->node->node.header.parentid, &key);
- ae->blocknr = key.objectid;
- ae->num_blocks = key.offset;
- ae->num_used = 0;
- return ret;
+ return 1;
}
-void print_leaf(struct leaf *l)
-{
- int i;
- int nr = l->header.nritems;
- struct item *item;
- struct extent_item *ei;
- printf("leaf %lu total ptrs %d free space %d\n", l->header.blocknr, nr,
- leaf_free_space(l));
- fflush(stdout);
- for (i = 0 ; i < nr ; i++) {
- item = l->items + i;
- printf("\titem %d key (%lu %u %lu) itemoff %d itemsize %d\n",
- i,
- item->key.objectid, item->key.flags, item->key.offset,
- item->offset, item->size);
- fflush(stdout);
- printf("\t\titem data %.*s\n", item->size, l->data+item->offset);
- ei = (struct extent_item *)(l->data + item->offset);
- printf("\t\textent data %u %lu\n", ei->refs, ei->owner);
- fflush(stdout);
- }
-}
-void print_tree(struct ctree_root *root, struct tree_buffer *t)
+/*
+ * search in extent tree to find a previous Metadata/Data extent item with
+ * min objecitd.
+ *
+ * returns 0 if something is found, 1 if nothing was found and < 0 on error
+ */
+int btrfs_previous_extent_item(struct btrfs_root *root,
+ struct btrfs_path *path, u64 min_objectid)
{
- int i;
- int nr;
- struct node *c;
+ struct btrfs_key found_key;
+ struct extent_buffer *leaf;
+ u32 nritems;
+ int ret;
- if (!t)
- return;
- c = &t->node;
- nr = c->header.nritems;
- if (c->header.blocknr != t->blocknr)
- BUG();
- if (is_leaf(c->header.flags)) {
- print_leaf((struct leaf *)c);
- return;
- }
- printf("node %lu level %d total ptrs %d free spc %lu\n", t->blocknr,
- node_level(c->header.flags), c->header.nritems,
- NODEPTRS_PER_BLOCK - c->header.nritems);
- fflush(stdout);
- for (i = 0; i < nr; i++) {
- printf("\tkey %d (%lu %u %lu) block %lu\n",
- i,
- c->keys[i].objectid, c->keys[i].flags, c->keys[i].offset,
- c->blockptrs[i]);
- fflush(stdout);
- }
- for (i = 0; i < nr; i++) {
- struct tree_buffer *next_buf = read_tree_block(root,
- c->blockptrs[i]);
- struct node *next = &next_buf->node;
- if (is_leaf(next->header.flags) &&
- node_level(c->header.flags) != 1)
- BUG();
- if (node_level(next->header.flags) !=
- node_level(c->header.flags) - 1)
- BUG();
- print_tree(root, next_buf);
- tree_block_release(root, next_buf);
+ while (1) {
+ if (path->slots[0] == 0) {
+ ret = btrfs_prev_leaf(root, path);
+ if (ret != 0)
+ return ret;
+ } else {
+ path->slots[0]--;
+ }
+ leaf = path->nodes[0];
+ nritems = btrfs_header_nritems(leaf);
+ if (nritems == 0)
+ return 1;
+ if (path->slots[0] == nritems)
+ path->slots[0]--;
+
+ btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
+ if (found_key.objectid < min_objectid)
+ break;
+ if (found_key.type == BTRFS_EXTENT_ITEM_KEY ||
+ found_key.type == BTRFS_METADATA_ITEM_KEY)
+ return 0;
+ if (found_key.objectid == min_objectid &&
+ found_key.type < BTRFS_EXTENT_ITEM_KEY)
+ break;
}
-
-}
-
-/* for testing only */
-int next_key(int i, int max_key) {
- return rand() % max_key;
- // return i;
+ return 1;
}
-int main() {
- struct ctree_root *root;
- struct key ins;
- struct key last = { (u64)-1, 0, 0};
- char *buf;
- int i;
- int num;
+/*
+ * Search in extent tree to found next meta/data extent
+ * Caller needs to check for no-hole or skinny metadata features.
+ */
+int btrfs_next_extent_item(struct btrfs_root *root,
+ struct btrfs_path *path, u64 max_objectid)
+{
+ struct btrfs_key found_key;
int ret;
- int run_size = 10000;
- int max_key = 100000000;
- int tree_size = 0;
- struct ctree_path path;
- struct ctree_super_block super;
-
- radix_tree_init();
-
-
- root = open_ctree("dbfile", &super);
- printf("root tree\n");
- print_tree(root, root->node);
- printf("map tree\n");
- print_tree(root->extent_root, root->extent_root->node);
-
- srand(55);
- for (i = 0; i < run_size; i++) {
- buf = malloc(64);
- num = next_key(i, max_key);
- // num = i;
- sprintf(buf, "string-%d", num);
- // printf("insert %d\n", num);
- ins.objectid = num;
- ins.offset = 0;
- ins.flags = 0;
- ret = insert_item(root, &ins, buf, strlen(buf));
- if (!ret)
- tree_size++;
- }
- printf("root used: %lu\n", root->alloc_extent->num_used);
- printf("root tree\n");
- // print_tree(root, root->node);
- printf("map tree\n");
- printf("map used: %lu\n", root->extent_root->alloc_extent->num_used);
- // print_tree(root->extent_root, root->extent_root->node);
- write_ctree_super(root, &super);
- close_ctree(root);
-
- root = open_ctree("dbfile", &super);
- printf("starting search\n");
- srand(55);
- for (i = 0; i < run_size; i++) {
- num = next_key(i, max_key);
- ins.objectid = num;
- init_path(&path);
- ret = search_slot(root, &ins, &path);
- if (ret) {
- print_tree(root, root->node);
- printf("unable to find %d\n", num);
- exit(1);
- }
- release_path(root, &path);
- }
- write_ctree_super(root, &super);
- close_ctree(root);
- root = open_ctree("dbfile", &super);
- printf("node %p level %d total ptrs %d free spc %lu\n", root->node,
- node_level(root->node->node.header.flags),
- root->node->node.header.nritems,
- NODEPTRS_PER_BLOCK - root->node->node.header.nritems);
- printf("all searches good, deleting some items\n");
- i = 0;
- srand(55);
- for (i = 0 ; i < run_size/4; i++) {
- num = next_key(i, max_key);
- ins.objectid = num;
- init_path(&path);
- ret = search_slot(root, &ins, &path);
+
+ while (1) {
+ ret = btrfs_next_item(root, path);
if (ret)
- continue;
- ret = del_item(root, &path);
- if (ret != 0)
- BUG();
- release_path(root, &path);
- tree_size--;
- }
- srand(128);
- for (i = 0; i < run_size; i++) {
- buf = malloc(64);
- num = next_key(i, max_key);
- sprintf(buf, "string-%d", num);
- ins.objectid = num;
- ret = insert_item(root, &ins, buf, strlen(buf));
- if (!ret)
- tree_size++;
- }
- write_ctree_super(root, &super);
- close_ctree(root);
- root = open_ctree("dbfile", &super);
- printf("starting search2\n");
- srand(128);
- for (i = 0; i < run_size; i++) {
- num = next_key(i, max_key);
- ins.objectid = num;
- init_path(&path);
- ret = search_slot(root, &ins, &path);
- if (ret) {
- print_tree(root, root->node);
- printf("unable to find %d\n", num);
- exit(1);
- }
- release_path(root, &path);
- }
- printf("starting big long delete run\n");
- while(root->node && root->node->node.header.nritems > 0) {
- struct leaf *leaf;
- int slot;
- ins.objectid = (u64)-1;
- init_path(&path);
- ret = search_slot(root, &ins, &path);
- if (ret == 0)
- BUG();
-
- leaf = &path.nodes[0]->leaf;
- slot = path.slots[0];
- if (slot != leaf->header.nritems)
- BUG();
- while(path.slots[0] > 0) {
- path.slots[0] -= 1;
- slot = path.slots[0];
- leaf = &path.nodes[0]->leaf;
-
- if (comp_keys(&last, &leaf->items[slot].key) <= 0)
- BUG();
- memcpy(&last, &leaf->items[slot].key, sizeof(last));
- ret = del_item(root, &path);
- if (ret != 0) {
- printf("del_item returned %d\n", ret);
- BUG();
- }
- tree_size--;
- }
- release_path(root, &path);
+ return ret;
+ btrfs_item_key_to_cpu(path->nodes[0], &found_key,
+ path->slots[0]);
+ if (found_key.objectid > max_objectid)
+ return 1;
+ if (found_key.type == BTRFS_EXTENT_ITEM_KEY ||
+ found_key.type == BTRFS_METADATA_ITEM_KEY)
+ return 0;
}
- write_ctree_super(root, &super);
- close_ctree(root);
- printf("tree size is now %d\n", tree_size);
- return 0;
}
projects / platform / upstream / btrfs-progs.git / blobdiff