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variable block size support

This commit is contained in:
Chris Mason 2007-03-14 14:14:43 -04:00 committed by David Woodhouse
parent 942050de0e
commit 7a0a809b4c
10 changed files with 238 additions and 300 deletions
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225
ctree.c
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@ -47,7 +47,7 @@ static int btrfs_cow_block(struct btrfs_root *root,
return 0;
}
cow = btrfs_alloc_free_block(root);
memcpy(&cow->node, &buf->node, sizeof(buf->node));
memcpy(&cow->node, &buf->node, root->blocksize);
btrfs_set_header_blocknr(&cow->node.header, cow->blocknr);
*cow_ret = cow;
btrfs_inc_ref(root, buf);
@ -72,11 +72,12 @@ static int btrfs_cow_block(struct btrfs_root *root,
* 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 btrfs_leaf *leaf)
static inline unsigned int leaf_data_end(struct btrfs_root *root,
struct btrfs_leaf *leaf)
{
u32 nr = btrfs_header_nritems(&leaf->header);
if (nr == 0)
return sizeof(leaf->data);
return BTRFS_LEAF_DATA_SIZE(root);
return btrfs_item_offset(leaf->items + nr - 1);
}
@ -85,12 +86,12 @@ static inline unsigned int leaf_data_end(struct btrfs_leaf *leaf)
* 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_leaf *leaf)
int btrfs_leaf_free_space(struct btrfs_root *root, struct btrfs_leaf *leaf)
{
int data_end = leaf_data_end(leaf);
int data_end = leaf_data_end(root, leaf);
int nritems = btrfs_header_nritems(&leaf->header);
char *items_end = (char *)(leaf->items + nritems + 1);
return (char *)(leaf->data + data_end) - (char *)items_end;
return (char *)(btrfs_leaf_data(leaf) + data_end) - (char *)items_end;
}
/*
@ -117,7 +118,8 @@ static int comp_keys(struct btrfs_disk_key *disk, struct btrfs_key *k2)
return 0;
}
static int check_node(struct btrfs_path *path, int level)
static int check_node(struct btrfs_root *root, struct btrfs_path *path,
int level)
{
int i;
struct btrfs_node *parent = NULL;
@ -131,22 +133,23 @@ static int check_node(struct btrfs_path *path, int level)
BUG_ON(nritems == 0);
if (parent) {
struct btrfs_disk_key *parent_key;
parent_key = &parent->keys[parent_slot];
BUG_ON(memcmp(parent_key, node->keys,
parent_key = &parent->ptrs[parent_slot].key;
BUG_ON(memcmp(parent_key, &node->ptrs[0].key,
sizeof(struct btrfs_disk_key)));
BUG_ON(btrfs_node_blockptr(parent, parent_slot) !=
btrfs_header_blocknr(&node->header));
}
BUG_ON(nritems > NODEPTRS_PER_BLOCK);
BUG_ON(nritems > BTRFS_NODEPTRS_PER_BLOCK(root));
for (i = 0; nritems > 1 && i < nritems - 2; i++) {
struct btrfs_key cpukey;
btrfs_disk_key_to_cpu(&cpukey, &node->keys[i + 1]);
BUG_ON(comp_keys(&node->keys[i], &cpukey) >= 0);
btrfs_disk_key_to_cpu(&cpukey, &node->ptrs[i + 1].key);
BUG_ON(comp_keys(&node->ptrs[i].key, &cpukey) >= 0);
}
return 0;
}
static int check_leaf(struct btrfs_path *path, int level)
static int check_leaf(struct btrfs_root *root, struct btrfs_path *path,
int level)
{
int i;
struct btrfs_leaf *leaf = &path->nodes[level]->leaf;
@ -157,14 +160,14 @@ static int check_leaf(struct btrfs_path *path, int level)
if (path->nodes[level + 1])
parent = &path->nodes[level + 1]->node;
parent_slot = path->slots[level + 1];
BUG_ON(btrfs_leaf_free_space(leaf) < 0);
BUG_ON(btrfs_leaf_free_space(root, leaf) < 0);
if (nritems == 0)
return 0;
if (parent) {
struct btrfs_disk_key *parent_key;
parent_key = &parent->keys[parent_slot];
parent_key = &parent->ptrs[parent_slot].key;
BUG_ON(memcmp(parent_key, &leaf->items[0].key,
sizeof(struct btrfs_disk_key)));
BUG_ON(btrfs_node_blockptr(parent, parent_slot) !=
@ -180,17 +183,18 @@ static int check_leaf(struct btrfs_path *path, int level)
if (i == 0) {
BUG_ON(btrfs_item_offset(leaf->items + i) +
btrfs_item_size(leaf->items + i) !=
LEAF_DATA_SIZE);
BTRFS_LEAF_DATA_SIZE(root));
}
}
return 0;
}
static int check_block(struct btrfs_path *path, int level)
static int check_block(struct btrfs_root *root, struct btrfs_path *path,
int level)
{
if (level == 0)
return check_leaf(path, level);
return check_node(path, level);
return check_leaf(root, path, level);
return check_node(root, path, level);
}
/*
@ -242,8 +246,8 @@ static int bin_search(struct btrfs_node *c, struct btrfs_key *key, int *slot)
key, btrfs_header_nritems(&c->header),
slot);
} else {
return generic_bin_search((void *)c->keys,
sizeof(struct btrfs_disk_key),
return generic_bin_search((void *)c->ptrs,
sizeof(struct btrfs_key_ptr),
key, btrfs_header_nritems(&c->header),
slot);
}
@ -311,7 +315,8 @@ static int balance_level(struct btrfs_root *root, struct btrfs_path *path,
}
parent = &parent_buf->node;
if (btrfs_header_nritems(&mid->header) > NODEPTRS_PER_BLOCK / 4)
if (btrfs_header_nritems(&mid->header) >
BTRFS_NODEPTRS_PER_BLOCK(root) / 4)
return 0;
left_buf = read_node_slot(root, parent_buf, pslot - 1);
@ -351,7 +356,8 @@ static int balance_level(struct btrfs_root *root, struct btrfs_path *path,
if (wret)
ret = wret;
} else {
memcpy(parent->keys + pslot + 1, right->keys,
memcpy(&parent->ptrs[pslot + 1].key,
&right->ptrs[0].key,
sizeof(struct btrfs_disk_key));
BUG_ON(list_empty(&parent_buf->dirty));
}
@ -387,7 +393,7 @@ static int balance_level(struct btrfs_root *root, struct btrfs_path *path,
ret = wret;
} else {
/* update the parent key to reflect our changes */
memcpy(parent->keys + pslot, mid->keys,
memcpy(&parent->ptrs[pslot].key, &mid->ptrs[0].key,
sizeof(struct btrfs_disk_key));
BUG_ON(list_empty(&parent_buf->dirty));
}
@ -407,7 +413,7 @@ static int balance_level(struct btrfs_root *root, struct btrfs_path *path,
}
}
/* double check we haven't messed things up */
check_block(path, level);
check_block(root, path, level);
if (orig_ptr != btrfs_node_blockptr(&path->nodes[level]->node,
path->slots[level]))
BUG();
@ -456,7 +462,7 @@ again:
BUG_ON(!cow && ins_len);
c = &b->node;
p->nodes[level] = b;
ret = check_block(p, level);
ret = check_block(root, p, level);
if (ret)
return -1;
ret = bin_search(c, key, &slot);
@ -465,7 +471,7 @@ again:
slot -= 1;
p->slots[level] = slot;
if (ins_len > 0 && btrfs_header_nritems(&c->header) ==
NODEPTRS_PER_BLOCK) {
BTRFS_NODEPTRS_PER_BLOCK(root)) {
int sret = split_node(root, p, level);
BUG_ON(sret > 0);
if (sret)
@ -488,7 +494,7 @@ again:
} else {
struct btrfs_leaf *l = (struct btrfs_leaf *)c;
p->slots[level] = slot;
if (ins_len > 0 && btrfs_leaf_free_space(l) <
if (ins_len > 0 && btrfs_leaf_free_space(root, l) <
sizeof(struct btrfs_item) + ins_len) {
int sret = split_leaf(root, p, ins_len);
BUG_ON(sret > 0);
@ -525,7 +531,7 @@ static int fixup_low_keys(struct btrfs_root *root,
if (!path->nodes[i])
break;
t = &path->nodes[i]->node;
memcpy(t->keys + tslot, key, sizeof(*key));
memcpy(&t->ptrs[tslot].key, key, sizeof(*key));
BUG_ON(list_empty(&path->nodes[i]->dirty));
if (tslot != 0)
break;
@ -552,7 +558,7 @@ static int push_node_left(struct btrfs_root *root, struct btrfs_buffer *dst_buf,
src_nritems = btrfs_header_nritems(&src->header);
dst_nritems = btrfs_header_nritems(&dst->header);
push_items = NODEPTRS_PER_BLOCK - dst_nritems;
push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems;
if (push_items <= 0) {
return 1;
}
@ -560,16 +566,12 @@ static int push_node_left(struct btrfs_root *root, struct btrfs_buffer *dst_buf,
if (src_nritems < push_items)
push_items = src_nritems;
memcpy(dst->keys + dst_nritems, src->keys,
push_items * sizeof(struct btrfs_disk_key));
memcpy(dst->blockptrs + dst_nritems, src->blockptrs,
push_items * sizeof(u64));
memcpy(dst->ptrs + dst_nritems, src->ptrs,
push_items * sizeof(struct btrfs_key_ptr));
if (push_items < src_nritems) {
memmove(src->keys, src->keys + push_items,
memmove(src->ptrs, src->ptrs + push_items,
(src_nritems - push_items) *
sizeof(struct btrfs_disk_key));
memmove(src->blockptrs, src->blockptrs + push_items,
(src_nritems - push_items) * sizeof(u64));
sizeof(struct btrfs_key_ptr));
}
btrfs_set_header_nritems(&src->header, src_nritems - push_items);
btrfs_set_header_nritems(&dst->header, dst_nritems + push_items);
@ -601,7 +603,7 @@ static int balance_node_right(struct btrfs_root *root,
src_nritems = btrfs_header_nritems(&src->header);
dst_nritems = btrfs_header_nritems(&dst->header);
push_items = NODEPTRS_PER_BLOCK - dst_nritems;
push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems;
if (push_items <= 0) {
return 1;
}
@ -613,14 +615,10 @@ static int balance_node_right(struct btrfs_root *root,
if (max_push < push_items)
push_items = max_push;
memmove(dst->keys + push_items, dst->keys,
dst_nritems * sizeof(struct btrfs_disk_key));
memmove(dst->blockptrs + push_items, dst->blockptrs,
dst_nritems * sizeof(u64));
memcpy(dst->keys, src->keys + src_nritems - push_items,
push_items * sizeof(struct btrfs_disk_key));
memcpy(dst->blockptrs, src->blockptrs + src_nritems - push_items,
push_items * sizeof(u64));
memmove(dst->ptrs + push_items, dst->ptrs,
dst_nritems * sizeof(struct btrfs_key_ptr));
memcpy(dst->ptrs, src->ptrs + src_nritems - push_items,
push_items * sizeof(struct btrfs_key_ptr));
btrfs_set_header_nritems(&src->header, src_nritems - push_items);
btrfs_set_header_nritems(&dst->header, dst_nritems + push_items);
@ -650,7 +648,7 @@ static int insert_new_root(struct btrfs_root *root,
t = btrfs_alloc_free_block(root);
c = &t->node;
memset(c, 0, sizeof(c));
memset(c, 0, root->blocksize);
btrfs_set_header_nritems(&c->header, 1);
btrfs_set_header_level(&c->header, level);
btrfs_set_header_blocknr(&c->header, t->blocknr);
@ -660,8 +658,8 @@ static int insert_new_root(struct btrfs_root *root,
if (btrfs_is_leaf(lower))
lower_key = &((struct btrfs_leaf *)lower)->items[0].key;
else
lower_key = lower->keys;
memcpy(c->keys, lower_key, sizeof(struct btrfs_disk_key));
lower_key = &lower->ptrs[0].key;
memcpy(&c->ptrs[0].key, lower_key, sizeof(struct btrfs_disk_key));
btrfs_set_node_blockptr(c, 0, path->nodes[level - 1]->blocknr);
/* the super has an extra ref to root->node */
btrfs_block_release(root, root->node);
@ -693,19 +691,15 @@ static int insert_ptr(struct btrfs_root *root,
nritems = btrfs_header_nritems(&lower->header);
if (slot > nritems)
BUG();
if (nritems == NODEPTRS_PER_BLOCK)
if (nritems == BTRFS_NODEPTRS_PER_BLOCK(root))
BUG();
if (slot != nritems) {
memmove(lower->keys + slot + 1, lower->keys + slot,
(nritems - slot) * sizeof(struct btrfs_disk_key));
memmove(lower->blockptrs + slot + 1, lower->blockptrs + slot,
(nritems - slot) * sizeof(u64));
memmove(lower->ptrs + slot + 1, lower->ptrs + slot,
(nritems - slot) * sizeof(struct btrfs_key_ptr));
}
memcpy(lower->keys + slot, key, sizeof(struct btrfs_disk_key));
memcpy(&lower->ptrs[slot].key, key, sizeof(struct btrfs_disk_key));
btrfs_set_node_blockptr(lower, slot, blocknr);
btrfs_set_header_nritems(&lower->header, nritems + 1);
if (lower->keys[1].objectid == 0)
BUG();
BUG_ON(list_empty(&path->nodes[level]->dirty));
return 0;
}
@ -747,17 +741,16 @@ static int split_node(struct btrfs_root *root, struct btrfs_path *path,
btrfs_set_header_parentid(&split->header,
btrfs_header_parentid(&root->node->node.header));
mid = (c_nritems + 1) / 2;
memcpy(split->keys, c->keys + mid,
(c_nritems - mid) * sizeof(struct btrfs_disk_key));
memcpy(split->blockptrs, c->blockptrs + mid,
(c_nritems - mid) * sizeof(u64));
memcpy(split->ptrs, c->ptrs + mid,
(c_nritems - mid) * sizeof(struct btrfs_key_ptr));
btrfs_set_header_nritems(&split->header, c_nritems - mid);
btrfs_set_header_nritems(&c->header, mid);
ret = 0;
BUG_ON(list_empty(&t->dirty));
wret = insert_ptr(root, path, split->keys, split_buffer->blocknr,
path->slots[level + 1] + 1, level + 1);
wret = insert_ptr(root, path, &split->ptrs[0].key,
split_buffer->blocknr, path->slots[level + 1] + 1,
level + 1);
if (wret)
ret = wret;
@ -825,7 +818,7 @@ static int push_leaf_right(struct btrfs_root *root, struct btrfs_path *path,
right_buf = read_tree_block(root, btrfs_node_blockptr(&upper->node,
slot + 1));
right = &right_buf->leaf;
free_space = btrfs_leaf_free_space(right);
free_space = btrfs_leaf_free_space(root, right);
if (free_space < data_size + sizeof(struct btrfs_item)) {
btrfs_block_release(root, right_buf);
return 1;
@ -833,7 +826,7 @@ static int push_leaf_right(struct btrfs_root *root, struct btrfs_path *path,
/* cow and double check */
btrfs_cow_block(root, right_buf, upper, slot + 1, &right_buf);
right = &right_buf->leaf;
free_space = btrfs_leaf_free_space(right);
free_space = btrfs_leaf_free_space(root, right);
if (free_space < data_size + sizeof(struct btrfs_item)) {
btrfs_block_release(root, right_buf);
return 1;
@ -857,15 +850,14 @@ static int push_leaf_right(struct btrfs_root *root, struct btrfs_path *path,
right_nritems = btrfs_header_nritems(&right->header);
/* push left to right */
push_space = btrfs_item_end(left->items + left_nritems - push_items);
push_space -= leaf_data_end(left);
push_space -= leaf_data_end(root, left);
/* make room in the right data area */
memmove(right->data + leaf_data_end(right) - push_space,
right->data + leaf_data_end(right),
LEAF_DATA_SIZE - leaf_data_end(right));
memmove(btrfs_leaf_data(right) + leaf_data_end(root, right) -
push_space, btrfs_leaf_data(right) + leaf_data_end(root, right),
BTRFS_LEAF_DATA_SIZE(root) - leaf_data_end(root, right));
/* copy from the left data area */
memcpy(right->data + LEAF_DATA_SIZE - push_space,
left->data + leaf_data_end(left),
push_space);
memcpy(btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) - push_space,
btrfs_leaf_data(left) + leaf_data_end(root, left), push_space);
memmove(right->items + push_items, right->items,
right_nritems * sizeof(struct btrfs_item));
/* copy the items from left to right */
@ -875,7 +867,7 @@ static int push_leaf_right(struct btrfs_root *root, struct btrfs_path *path,
/* update the item pointers */
right_nritems += push_items;
btrfs_set_header_nritems(&right->header, right_nritems);
push_space = LEAF_DATA_SIZE;
push_space = BTRFS_LEAF_DATA_SIZE(root);
for (i = 0; i < right_nritems; i++) {
btrfs_set_item_offset(right->items + i, push_space -
btrfs_item_size(right->items + i));
@ -886,7 +878,7 @@ static int push_leaf_right(struct btrfs_root *root, struct btrfs_path *path,
BUG_ON(list_empty(&left_buf->dirty));
BUG_ON(list_empty(&right_buf->dirty));
memcpy(upper->node.keys + slot + 1,
memcpy(&upper->node.ptrs[slot + 1].key,
&right->items[0].key, sizeof(struct btrfs_disk_key));
BUG_ON(list_empty(&upper->dirty));
@ -932,7 +924,7 @@ static int push_leaf_left(struct btrfs_root *root, struct btrfs_path *path,
t = read_tree_block(root, btrfs_node_blockptr(&path->nodes[1]->node,
slot - 1));
left = &t->leaf;
free_space = btrfs_leaf_free_space(left);
free_space = btrfs_leaf_free_space(root, left);
if (free_space < data_size + sizeof(struct btrfs_item)) {
btrfs_block_release(root, t);
return 1;
@ -941,7 +933,7 @@ static int push_leaf_left(struct btrfs_root *root, struct btrfs_path *path,
/* cow and double check */
btrfs_cow_block(root, t, path->nodes[1], slot - 1, &t);
left = &t->leaf;
free_space = btrfs_leaf_free_space(left);
free_space = btrfs_leaf_free_space(root, left);
if (free_space < data_size + sizeof(struct btrfs_item)) {
btrfs_block_release(root, t);
return 1;
@ -964,17 +956,19 @@ static int push_leaf_left(struct btrfs_root *root, struct btrfs_path *path,
/* push data from right to left */
memcpy(left->items + btrfs_header_nritems(&left->header),
right->items, push_items * sizeof(struct btrfs_item));
push_space = LEAF_DATA_SIZE -
push_space = BTRFS_LEAF_DATA_SIZE(root) -
btrfs_item_offset(right->items + push_items -1);
memcpy(left->data + leaf_data_end(left) - push_space,
right->data + btrfs_item_offset(right->items + push_items - 1),
memcpy(btrfs_leaf_data(left) + leaf_data_end(root, left) - push_space,
btrfs_leaf_data(right) +
btrfs_item_offset(right->items + push_items - 1),
push_space);
old_left_nritems = btrfs_header_nritems(&left->header);
BUG_ON(old_left_nritems < 0);
for (i = old_left_nritems; i < old_left_nritems + push_items; i++) {
u16 ioff = btrfs_item_offset(left->items + i);
btrfs_set_item_offset(left->items + i, ioff - (LEAF_DATA_SIZE -
u32 ioff = btrfs_item_offset(left->items + i);
btrfs_set_item_offset(left->items + i, ioff -
(BTRFS_LEAF_DATA_SIZE(root) -
btrfs_item_offset(left->items +
old_left_nritems - 1)));
}
@ -982,16 +976,17 @@ static int push_leaf_left(struct btrfs_root *root, struct btrfs_path *path,
/* fixup right node */
push_space = btrfs_item_offset(right->items + push_items - 1) -
leaf_data_end(right);
memmove(right->data + LEAF_DATA_SIZE - push_space, right->data +
leaf_data_end(right), push_space);
leaf_data_end(root, right);
memmove(btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) -
push_space, btrfs_leaf_data(right) +
leaf_data_end(root, right), push_space);
memmove(right->items, right->items + push_items,
(btrfs_header_nritems(&right->header) - push_items) *
sizeof(struct btrfs_item));
btrfs_set_header_nritems(&right->header,
btrfs_header_nritems(&right->header) -
push_items);
push_space = LEAF_DATA_SIZE;
push_space = BTRFS_LEAF_DATA_SIZE(root);
for (i = 0; i < btrfs_header_nritems(&right->header); i++) {
btrfs_set_item_offset(right->items + i, push_space -
@ -1051,12 +1046,12 @@ static int split_leaf(struct btrfs_root *root, struct btrfs_path *path,
if (wret < 0)
return wret;
}
l_buf = path->nodes[0];
l = &l_buf->leaf;
/* did the pushes work? */
if (btrfs_leaf_free_space(l) >= sizeof(struct btrfs_item) + data_size)
if (btrfs_leaf_free_space(root, l) >=
sizeof(struct btrfs_item) + data_size)
return 0;
if (!path->nodes[1]) {
@ -1071,16 +1066,16 @@ static int split_leaf(struct btrfs_root *root, struct btrfs_path *path,
BUG_ON(!right_buffer);
BUG_ON(mid == nritems);
right = &right_buffer->leaf;
memset(right, 0, sizeof(*right));
memset(&right->header, 0, sizeof(right->header));
if (mid <= slot) {
/* FIXME, just alloc a new leaf here */
if (leaf_space_used(l, mid, nritems - mid) + space_needed >
LEAF_DATA_SIZE)
BTRFS_LEAF_DATA_SIZE(root))
BUG();
} else {
/* FIXME, just alloc a new leaf here */
if (leaf_space_used(l, 0, mid + 1) + space_needed >
LEAF_DATA_SIZE)
BTRFS_LEAF_DATA_SIZE(root))
BUG();
}
btrfs_set_header_nritems(&right->header, nritems - mid);
@ -1088,15 +1083,18 @@ static int split_leaf(struct btrfs_root *root, struct btrfs_path *path,
btrfs_set_header_level(&right->header, 0);
btrfs_set_header_parentid(&right->header,
btrfs_header_parentid(&root->node->node.header));
data_copy_size = btrfs_item_end(l->items + mid) - leaf_data_end(l);
data_copy_size = btrfs_item_end(l->items + mid) -
leaf_data_end(root, l);
memcpy(right->items, l->items + mid,
(nritems - mid) * sizeof(struct btrfs_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 - btrfs_item_end(l->items + mid);
memcpy(btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) -
data_copy_size, btrfs_leaf_data(l) +
leaf_data_end(root, l), data_copy_size);
rt_data_off = BTRFS_LEAF_DATA_SIZE(root) -
btrfs_item_end(l->items + mid);
for (i = 0; i < btrfs_header_nritems(&right->header); i++) {
u16 ioff = btrfs_item_offset(right->items + i);
u32 ioff = btrfs_item_offset(right->items + i);
btrfs_set_item_offset(right->items + i, ioff + rt_data_off);
}
@ -1156,9 +1154,9 @@ int btrfs_insert_item(struct btrfs_root *root, struct btrfs_key *cpu_key,
leaf = &leaf_buf->leaf;
nritems = btrfs_header_nritems(&leaf->header);
data_end = leaf_data_end(leaf);
data_end = leaf_data_end(root, leaf);
if (btrfs_leaf_free_space(leaf) <
if (btrfs_leaf_free_space(root, leaf) <
sizeof(struct btrfs_item) + data_size)
BUG();
@ -1173,7 +1171,7 @@ int btrfs_insert_item(struct btrfs_root *root, struct btrfs_key *cpu_key,
*/
/* first correct the data pointers */
for (i = slot; i < nritems; i++) {
u16 ioff = btrfs_item_offset(leaf->items + i);
u32 ioff = btrfs_item_offset(leaf->items + i);
btrfs_set_item_offset(leaf->items + i,
ioff - data_size);
}
@ -1183,7 +1181,8 @@ int btrfs_insert_item(struct btrfs_root *root, struct btrfs_key *cpu_key,
(nritems - slot) * sizeof(struct btrfs_item));
/* shift the data */
memmove(leaf->data + data_end - data_size, leaf->data +
memmove(btrfs_leaf_data(leaf) + data_end - data_size,
btrfs_leaf_data(leaf) +
data_end, old_data - data_end);
data_end = old_data;
}
@ -1192,7 +1191,7 @@ int btrfs_insert_item(struct btrfs_root *root, struct btrfs_key *cpu_key,
sizeof(struct btrfs_disk_key));
btrfs_set_item_offset(leaf->items + slot, data_end - data_size);
btrfs_set_item_size(leaf->items + slot, data_size);
memcpy(leaf->data + data_end - data_size, data, data_size);
memcpy(btrfs_leaf_data(leaf) + data_end - data_size, data, data_size);
btrfs_set_header_nritems(&leaf->header, nritems + 1);
ret = 0;
@ -1200,9 +1199,9 @@ int btrfs_insert_item(struct btrfs_root *root, struct btrfs_key *cpu_key,
ret = fixup_low_keys(root, &path, &disk_key, 1);
BUG_ON(list_empty(&leaf_buf->dirty));
if (btrfs_leaf_free_space(leaf) < 0)
if (btrfs_leaf_free_space(root, leaf) < 0)
BUG();
check_leaf(&path, 0);
check_leaf(root, &path, 0);
out:
btrfs_release_path(root, &path);
return ret;
@ -1227,11 +1226,8 @@ static int del_ptr(struct btrfs_root *root, struct btrfs_path *path, int level,
node = &parent->node;
nritems = btrfs_header_nritems(&node->header);
if (slot != nritems -1) {
memmove(node->keys + slot, node->keys + slot + 1,
sizeof(struct btrfs_disk_key) * (nritems - slot - 1));
memmove(node->blockptrs + slot,
node->blockptrs + slot + 1,
sizeof(u64) * (nritems - slot - 1));
memmove(node->ptrs + slot, node->ptrs + slot + 1,
sizeof(struct btrfs_key_ptr) * (nritems - slot - 1));
}
nritems--;
btrfs_set_header_nritems(&node->header, nritems);
@ -1240,7 +1236,8 @@ static int del_ptr(struct btrfs_root *root, struct btrfs_path *path, int level,
/* just turn the root into a leaf and break */
btrfs_set_header_level(&root->node->node.header, 0);
} else if (slot == 0) {
wret = fixup_low_keys(root, path, node->keys, level + 1);
wret = fixup_low_keys(root, path, &node->ptrs[0].key,
level + 1);
if (wret)
ret = wret;
}
@ -1272,12 +1269,12 @@ int btrfs_del_item(struct btrfs_root *root, struct btrfs_path *path)
if (slot != nritems - 1) {
int i;
int data_end = leaf_data_end(leaf);
memmove(leaf->data + data_end + dsize,
leaf->data + data_end,
int data_end = leaf_data_end(root, leaf);
memmove(btrfs_leaf_data(leaf) + data_end + dsize,
btrfs_leaf_data(leaf) + data_end,
doff - data_end);
for (i = slot + 1; i < nritems; i++) {
u16 ioff = btrfs_item_offset(leaf->items + i);
u32 ioff = btrfs_item_offset(leaf->items + i);
btrfs_set_item_offset(leaf->items + i, ioff + dsize);
}
memmove(leaf->items + slot, leaf->items + slot + 1,
@ -1311,7 +1308,7 @@ int btrfs_del_item(struct btrfs_root *root, struct btrfs_path *path)
BUG_ON(list_empty(&leaf_buf->dirty));
/* delete the leaf if it is mostly empty */
if (used < LEAF_DATA_SIZE / 3) {
if (used < BTRFS_LEAF_DATA_SIZE(root) / 3) {
/* push_leaf_left fixes the path.
* make sure the path still points to our leaf
* for possible call to del_ptr below

62
ctree.h
View File

@ -5,7 +5,6 @@
#include "kerncompat.h"
#define BTRFS_MAGIC "_BtRfS_M"
#define BTRFS_BLOCKSIZE 1024
#define BTRFS_ROOT_TREE_OBJECTID 1
#define BTRFS_EXTENT_TREE_OBJECTID 2
@ -52,8 +51,11 @@ struct btrfs_header {
} __attribute__ ((__packed__));
#define BTRFS_MAX_LEVEL 8
#define NODEPTRS_PER_BLOCK ((BTRFS_BLOCKSIZE - sizeof(struct btrfs_header)) / \
(sizeof(struct btrfs_disk_key) + sizeof(u64)))
#define BTRFS_NODEPTRS_PER_BLOCK(r) (((r)->blocksize - \
sizeof(struct btrfs_header)) / \
(sizeof(struct btrfs_disk_key) + sizeof(u64)))
#define __BTRFS_LEAF_DATA_SIZE(bs) ((bs) - sizeof(struct btrfs_header))
#define BTRFS_LEAF_DATA_SIZE(r) (__BTRFS_LEAF_DATA_SIZE(r->blocksize))
struct btrfs_buffer;
@ -86,6 +88,7 @@ struct btrfs_root {
int ref_cows;
struct btrfs_root_item root_item;
struct btrfs_key root_key;
u32 blocksize;
};
/*
@ -97,7 +100,7 @@ struct btrfs_super_block {
__le64 blocknr; /* this block number */
__le32 csum;
__le64 magic;
__le16 blocksize;
__le32 blocksize;
__le64 generation;
__le64 root;
__le64 total_blocks;
@ -111,7 +114,7 @@ struct btrfs_super_block {
*/
struct btrfs_item {
struct btrfs_disk_key key;
__le16 offset;
__le32 offset;
__le16 size;
} __attribute__ ((__packed__));
@ -122,24 +125,23 @@ struct btrfs_item {
* The data is separate from the items to get the keys closer together
* during searches.
*/
#define LEAF_DATA_SIZE (BTRFS_BLOCKSIZE - sizeof(struct btrfs_header))
struct btrfs_leaf {
struct btrfs_header header;
union {
struct btrfs_item items[LEAF_DATA_SIZE/
sizeof(struct btrfs_item)];
u8 data[BTRFS_BLOCKSIZE - sizeof(struct btrfs_header)];
};
struct btrfs_item items[];
} __attribute__ ((__packed__));
/*
* all non-leaf blocks are nodes, they hold only keys and pointers to
* other blocks
*/
struct btrfs_key_ptr {
struct btrfs_disk_key key;
__le64 blockptr;
} __attribute__ ((__packed__));
struct btrfs_node {
struct btrfs_header header;
struct btrfs_disk_key keys[NODEPTRS_PER_BLOCK];
__le64 blockptrs[NODEPTRS_PER_BLOCK];
struct btrfs_key_ptr ptrs[];
} __attribute__ ((__packed__));
/*
@ -186,28 +188,28 @@ static inline void btrfs_set_extent_refs(struct btrfs_extent_item *ei, u32 val)
static inline u64 btrfs_node_blockptr(struct btrfs_node *n, int nr)
{
return le64_to_cpu(n->blockptrs[nr]);
return le64_to_cpu(n->ptrs[nr].blockptr);
}
static inline void btrfs_set_node_blockptr(struct btrfs_node *n, int nr,
u64 val)
{
n->blockptrs[nr] = cpu_to_le64(val);
n->ptrs[nr].blockptr = cpu_to_le64(val);
}
static inline u16 btrfs_item_offset(struct btrfs_item *item)
static inline u32 btrfs_item_offset(struct btrfs_item *item)
{
return le16_to_cpu(item->offset);
return le32_to_cpu(item->offset);
}
static inline void btrfs_set_item_offset(struct btrfs_item *item, u16 val)
static inline void btrfs_set_item_offset(struct btrfs_item *item, u32 val)
{
item->offset = cpu_to_le16(val);
item->offset = cpu_to_le32(val);
}
static inline u16 btrfs_item_end(struct btrfs_item *item)
static inline u32 btrfs_item_end(struct btrfs_item *item)
{
return le16_to_cpu(item->offset) + le16_to_cpu(item->size);
return le32_to_cpu(item->offset) + le16_to_cpu(item->size);
}
static inline u16 btrfs_item_size(struct btrfs_item *item)
@ -390,20 +392,26 @@ static inline void btrfs_set_super_blocks_used(struct btrfs_super_block *s,
s->blocks_used = cpu_to_le64(val);
}
static inline u16 btrfs_super_blocksize(struct btrfs_super_block *s)
static inline u32 btrfs_super_blocksize(struct btrfs_super_block *s)
{
return le16_to_cpu(s->blocksize);
return le32_to_cpu(s->blocksize);
}
static inline void btrfs_set_super_blocksize(struct btrfs_super_block *s,
u16 val)
u32 val)
{
s->blocksize = cpu_to_le16(val);
s->blocksize = cpu_to_le32(val);
}
static inline u8 *btrfs_leaf_data(struct btrfs_leaf *l)
{
return (u8 *)l->items;
}
/* helper function to cast into the data area of the leaf. */
#define btrfs_item_ptr(leaf, slot, type) \
((type *)((leaf)->data + btrfs_item_offset((leaf)->items + (slot))))
((type *)(btrfs_leaf_data(leaf) + \
btrfs_item_offset((leaf)->items + (slot))))
struct btrfs_buffer *btrfs_alloc_free_block(struct btrfs_root *root);
int btrfs_inc_ref(struct btrfs_root *root, struct btrfs_buffer *buf);
@ -416,7 +424,7 @@ int btrfs_del_item(struct btrfs_root *root, struct btrfs_path *path);
int btrfs_insert_item(struct btrfs_root *root, struct btrfs_key *key,
void *data, int data_size);
int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path);
int btrfs_leaf_free_space(struct btrfs_leaf *leaf);
int btrfs_leaf_free_space(struct btrfs_root *root, struct btrfs_leaf *leaf);
int btrfs_drop_snapshot(struct btrfs_root *root, struct btrfs_buffer *snap);
int btrfs_finish_extent_commit(struct btrfs_root *root);
int btrfs_del_root(struct btrfs_root *root, struct btrfs_key *key);

42
disk-io.c
View File

@ -46,7 +46,8 @@ struct btrfs_buffer *alloc_tree_block(struct btrfs_root *root, u64 blocknr)
{
struct btrfs_buffer *buf;
int ret;
buf = malloc(sizeof(struct btrfs_buffer));
buf = malloc(sizeof(struct btrfs_buffer) + root->blocksize);
if (!buf)
return buf;
allocated_blocks++;
@ -84,7 +85,7 @@ struct btrfs_buffer *find_tree_block(struct btrfs_root *root, u64 blocknr)
struct btrfs_buffer *read_tree_block(struct btrfs_root *root, u64 blocknr)
{
loff_t offset = blocknr * BTRFS_BLOCKSIZE;
loff_t offset = blocknr * root->blocksize;
struct btrfs_buffer *buf;
int ret;
@ -95,8 +96,8 @@ struct btrfs_buffer *read_tree_block(struct btrfs_root *root, u64 blocknr)
buf = alloc_tree_block(root, blocknr);
if (!buf)
return NULL;
ret = pread(root->fp, &buf->node, BTRFS_BLOCKSIZE, offset);
if (ret != BTRFS_BLOCKSIZE) {
ret = pread(root->fp, &buf->node, root->blocksize, offset);
if (ret != root->blocksize) {
free(buf);
return NULL;
}
@ -127,13 +128,13 @@ int clean_tree_block(struct btrfs_root *root, struct btrfs_buffer *buf)
int write_tree_block(struct btrfs_root *root, struct btrfs_buffer *buf)
{
u64 blocknr = buf->blocknr;
loff_t offset = blocknr * BTRFS_BLOCKSIZE;
loff_t offset = blocknr * root->blocksize;
int ret;
if (buf->blocknr != btrfs_header_blocknr(&buf->node.header))
BUG();
ret = pwrite(root->fp, &buf->node, BTRFS_BLOCKSIZE, offset);
if (ret != BTRFS_BLOCKSIZE)
ret = pwrite(root->fp, &buf->node, root->blocksize, offset);
if (ret != root->blocksize)
return ret;
return 0;
}
@ -215,7 +216,8 @@ int btrfs_commit_transaction(struct btrfs_root *root,
return ret;
}
static int __setup_root(struct btrfs_root *root, u64 objectid, int fp)
static int __setup_root(struct btrfs_super_block *super,
struct btrfs_root *root, u64 objectid, int fp)
{
INIT_LIST_HEAD(&root->trans);
INIT_LIST_HEAD(&root->cache);
@ -223,6 +225,8 @@ static int __setup_root(struct btrfs_root *root, u64 objectid, int fp)
root->fp = fp;
root->node = NULL;
root->commit_root = NULL;
root->blocksize = btrfs_super_blocksize(super);
root->ref_cows = 0;
memset(&root->current_insert, 0, sizeof(root->current_insert));
memset(&root->last_insert, 0, sizeof(root->last_insert));
memset(&root->root_key, 0, sizeof(root->root_key));
@ -230,19 +234,19 @@ static int __setup_root(struct btrfs_root *root, u64 objectid, int fp)
return 0;
}
static int find_and_setup_root(struct btrfs_root *tree_root, u64 objectid,
struct btrfs_root *root, int fp)
static int find_and_setup_root(struct btrfs_super_block *super,
struct btrfs_root *tree_root, u64 objectid,
struct btrfs_root *root, int fp)
{
int ret;
__setup_root(root, objectid, fp);
__setup_root(super, root, objectid, fp);
ret = btrfs_find_last_root(tree_root, objectid,
&root->root_item, &root->root_key);
BUG_ON(ret);
root->node = read_tree_block(root,
btrfs_root_blocknr(&root->root_item));
root->ref_cows = 0;
BUG_ON(!root->node);
return 0;
}
@ -277,28 +281,28 @@ struct btrfs_root *open_ctree(char *filename, struct btrfs_super_block *super)
INIT_RADIX_TREE(&tree_root->cache_radix, GFP_KERNEL);
ret = pread(fp, super, sizeof(struct btrfs_super_block),
BTRFS_SUPER_INFO_OFFSET(BTRFS_BLOCKSIZE));
BTRFS_SUPER_INFO_OFFSET);
if (ret == 0 || btrfs_super_root(super) == 0) {
printf("making new FS!\n");
ret = mkfs(fp, 0, BTRFS_BLOCKSIZE);
ret = mkfs(fp, 0, 1024);
if (ret)
return NULL;
ret = pread(fp, super, sizeof(struct btrfs_super_block),
BTRFS_SUPER_INFO_OFFSET(BTRFS_BLOCKSIZE));
BTRFS_SUPER_INFO_OFFSET);
if (ret != sizeof(struct btrfs_super_block))
return NULL;
}
BUG_ON(ret < 0);
__setup_root(tree_root, BTRFS_ROOT_TREE_OBJECTID, fp);
__setup_root(super, tree_root, BTRFS_ROOT_TREE_OBJECTID, fp);
tree_root->node = read_tree_block(tree_root, btrfs_super_root(super));
BUG_ON(!tree_root->node);
ret = find_and_setup_root(tree_root, BTRFS_EXTENT_TREE_OBJECTID,
ret = find_and_setup_root(super, tree_root, BTRFS_EXTENT_TREE_OBJECTID,
extent_root, fp);
BUG_ON(ret);
ret = find_and_setup_root(tree_root, BTRFS_FS_TREE_OBJECTID,
ret = find_and_setup_root(super, tree_root, BTRFS_FS_TREE_OBJECTID,
root, fp);
BUG_ON(ret);
@ -313,7 +317,7 @@ int write_ctree_super(struct btrfs_root *root, struct btrfs_super_block *s)
int ret;
btrfs_set_super_root(s, root->tree_root->node->blocknr);
ret = pwrite(root->fp, s, sizeof(*s),
BTRFS_SUPER_INFO_OFFSET(BTRFS_BLOCKSIZE));
BTRFS_SUPER_INFO_OFFSET);
if (ret != sizeof(*s)) {
fprintf(stderr, "failed to write new super block err %d\n", ret);
return ret;

9
disk-io.h
View File

@ -5,12 +5,12 @@
struct btrfs_buffer {
u64 blocknr;
int count;
struct list_head dirty;
struct list_head cache;
union {
struct btrfs_node node;
struct btrfs_leaf leaf;
};
struct list_head dirty;
struct list_head cache;
};
struct btrfs_buffer *read_tree_block(struct btrfs_root *root, u64 blocknr);
@ -24,9 +24,8 @@ struct btrfs_root *open_ctree(char *filename, struct btrfs_super_block *s);
int close_ctree(struct btrfs_root *root, struct btrfs_super_block *s);
void btrfs_block_release(struct btrfs_root *root, struct btrfs_buffer *buf);
int write_ctree_super(struct btrfs_root *root, struct btrfs_super_block *s);
int mkfs(int fd, u64 num_blocks, u16 blocksize);
int mkfs(int fd, u64 num_blocks, u32 blocksize);
#define BTRFS_SUPER_INFO_OFFSET(bs) (16 * (bs))
#define BTRFS_SUPER_INFO_OFFSET (16 * 1024)
#endif

6
extent-tree.c
View File

@ -143,7 +143,6 @@ static int __free_extent(struct btrfs_root *root, u64 blocknr, u64 num_blocks)
struct btrfs_key key;
struct btrfs_root *extent_root = root->extent_root;
int ret;
struct btrfs_item *item;
struct btrfs_extent_item *ei;
struct btrfs_key ins;
u32 refs;
@ -161,9 +160,8 @@ static int __free_extent(struct btrfs_root *root, u64 blocknr, u64 num_blocks)
printf("failed to find %Lu\n", key.objectid);
BUG();
}
item = path.nodes[0]->leaf.items + path.slots[0];
ei = (struct btrfs_extent_item *)(path.nodes[0]->leaf.data +
btrfs_item_offset(item));
ei = btrfs_item_ptr(&path.nodes[0]->leaf, path.slots[0],
struct btrfs_extent_item);
BUG_ON(ei->refs == 0);
refs = btrfs_extent_refs(ei) - 1;
btrfs_set_extent_refs(ei, refs);

171
mkfs.c
View File

@ -10,19 +10,20 @@
#include "ctree.h"
#include "disk-io.h"
int mkfs(int fd, u64 num_blocks, u16 blocksize)
int mkfs(int fd, u64 num_blocks, u32 blocksize)
{
struct btrfs_super_block super;
struct btrfs_leaf empty_leaf;
struct btrfs_leaf *empty_leaf;
struct btrfs_root_item root_item;
struct btrfs_item item;
struct btrfs_extent_item extent_item;
char *block;
int ret;
u16 itemoff;
u32 itemoff;
u32 start_block = BTRFS_SUPER_INFO_OFFSET / blocksize;
btrfs_set_super_blocknr(&super, 16);
btrfs_set_super_root(&super, 17);
btrfs_set_super_blocknr(&super, start_block);
btrfs_set_super_root(&super, start_block + 1);
strcpy((char *)(&super.magic), BTRFS_MAGIC);
btrfs_set_super_blocksize(&super, blocksize);
btrfs_set_super_total_blocks(&super, num_blocks);
@ -32,168 +33,98 @@ int mkfs(int fd, u64 num_blocks, u16 blocksize)
memset(block, 0, blocksize);
BUG_ON(sizeof(super) > blocksize);
memcpy(block, &super, sizeof(super));
ret = pwrite(fd, block, blocksize, BTRFS_SUPER_INFO_OFFSET(blocksize));
ret = pwrite(fd, block, blocksize, BTRFS_SUPER_INFO_OFFSET);
BUG_ON(ret != blocksize);
/* create the tree of root objects */
memset(&empty_leaf, 0, sizeof(empty_leaf));
btrfs_set_header_parentid(&empty_leaf.header, BTRFS_ROOT_TREE_OBJECTID);
btrfs_set_header_blocknr(&empty_leaf.header, 17);
btrfs_set_header_nritems(&empty_leaf.header, 2);
empty_leaf = malloc(blocksize);
memset(empty_leaf, 0, blocksize);
btrfs_set_header_parentid(&empty_leaf->header,
BTRFS_ROOT_TREE_OBJECTID);
btrfs_set_header_blocknr(&empty_leaf->header, start_block + 1);
btrfs_set_header_nritems(&empty_leaf->header, 2);
/* create the items for the root tree */
btrfs_set_root_blocknr(&root_item, 18);
btrfs_set_root_blocknr(&root_item, start_block + 2);
btrfs_set_root_refs(&root_item, 1);
itemoff = LEAF_DATA_SIZE - sizeof(root_item);
itemoff = __BTRFS_LEAF_DATA_SIZE(blocksize) - sizeof(root_item);
btrfs_set_item_offset(&item, itemoff);
btrfs_set_item_size(&item, sizeof(root_item));
btrfs_set_key_objectid(&item.key, BTRFS_EXTENT_TREE_OBJECTID);
btrfs_set_key_offset(&item.key, 0);
btrfs_set_key_flags(&item.key, 0);
memcpy(empty_leaf.items, &item, sizeof(item));
memcpy(empty_leaf.data + itemoff, &root_item, sizeof(root_item));
memcpy(empty_leaf->items, &item, sizeof(item));
memcpy(btrfs_leaf_data(empty_leaf) + itemoff,
&root_item, sizeof(root_item));
btrfs_set_root_blocknr(&root_item, 19);
btrfs_set_root_blocknr(&root_item, start_block + 3);
itemoff = itemoff - sizeof(root_item);
btrfs_set_item_offset(&item, itemoff);
btrfs_set_key_objectid(&item.key, BTRFS_FS_TREE_OBJECTID);
memcpy(empty_leaf.items + 1, &item, sizeof(item));
memcpy(empty_leaf.data + itemoff, &root_item, sizeof(root_item));
ret = pwrite(fd, &empty_leaf, blocksize, 17 * blocksize);
memcpy(empty_leaf->items + 1, &item, sizeof(item));
memcpy(btrfs_leaf_data(empty_leaf) + itemoff,
&root_item, sizeof(root_item));
ret = pwrite(fd, empty_leaf, blocksize, (start_block + 1) * blocksize);
/* create the items for the extent tree */
btrfs_set_header_parentid(&empty_leaf.header,
btrfs_set_header_parentid(&empty_leaf->header,
BTRFS_EXTENT_TREE_OBJECTID);
btrfs_set_header_blocknr(&empty_leaf.header, 18);
btrfs_set_header_nritems(&empty_leaf.header, 4);
btrfs_set_header_blocknr(&empty_leaf->header, start_block + 2);
btrfs_set_header_nritems(&empty_leaf->header, 4);
/* item1, reserve blocks 0-16 */
btrfs_set_key_objectid(&item.key, 0);
btrfs_set_key_offset(&item.key, 17);
btrfs_set_key_offset(&item.key, start_block + 1);
btrfs_set_key_flags(&item.key, 0);
itemoff = LEAF_DATA_SIZE - sizeof(struct btrfs_extent_item);
itemoff = __BTRFS_LEAF_DATA_SIZE(blocksize) -
sizeof(struct btrfs_extent_item);
btrfs_set_item_offset(&item, itemoff);
btrfs_set_item_size(&item, sizeof(struct btrfs_extent_item));
btrfs_set_extent_refs(&extent_item, 1);
btrfs_set_extent_owner(&extent_item, 0);
memcpy(empty_leaf.items, &item, sizeof(item));
memcpy(empty_leaf.data + btrfs_item_offset(&item), &extent_item,
btrfs_item_size(&item));
memcpy(empty_leaf->items, &item, sizeof(item));
memcpy(btrfs_leaf_data(empty_leaf) + btrfs_item_offset(&item),
&extent_item, btrfs_item_size(&item));
/* item2, give block 17 to the root */
btrfs_set_key_objectid(&item.key, 17);
btrfs_set_key_objectid(&item.key, start_block + 1);
btrfs_set_key_offset(&item.key, 1);
itemoff = itemoff - sizeof(struct btrfs_extent_item);
btrfs_set_item_offset(&item, itemoff);
btrfs_set_extent_owner(&extent_item, BTRFS_ROOT_TREE_OBJECTID);
memcpy(empty_leaf.items + 1, &item, sizeof(item));
memcpy(empty_leaf.data + btrfs_item_offset(&item), &extent_item,
btrfs_item_size(&item));
memcpy(empty_leaf->items + 1, &item, sizeof(item));
memcpy(btrfs_leaf_data(empty_leaf) + btrfs_item_offset(&item),
&extent_item, btrfs_item_size(&item));
/* item3, give block 18 to the extent root */
btrfs_set_key_objectid(&item.key, 18);
btrfs_set_key_objectid(&item.key, start_block + 2);
btrfs_set_key_offset(&item.key, 1);
itemoff = itemoff - sizeof(struct btrfs_extent_item);
btrfs_set_item_offset(&item, itemoff);
btrfs_set_extent_owner(&extent_item, BTRFS_EXTENT_TREE_OBJECTID);
memcpy(empty_leaf.items + 2, &item, sizeof(item));
memcpy(empty_leaf.data + btrfs_item_offset(&item), &extent_item,
btrfs_item_size(&item));
memcpy(empty_leaf->items + 2, &item, sizeof(item));
memcpy(btrfs_leaf_data(empty_leaf) + btrfs_item_offset(&item),
&extent_item, btrfs_item_size(&item));
/* item4, give block 19 to the FS root */
btrfs_set_key_objectid(&item.key, 19);
btrfs_set_key_objectid(&item.key, start_block + 3);
btrfs_set_key_offset(&item.key, 1);
itemoff = itemoff - sizeof(struct btrfs_extent_item);
btrfs_set_item_offset(&item, itemoff);
btrfs_set_extent_owner(&extent_item, BTRFS_FS_TREE_OBJECTID);
memcpy(empty_leaf.items + 3, &item, sizeof(item));
memcpy(empty_leaf.data + btrfs_item_offset(&item), &extent_item,
btrfs_item_size(&item));
ret = pwrite(fd, &empty_leaf, blocksize, 18 * blocksize);
if (ret != sizeof(empty_leaf))
memcpy(empty_leaf->items + 3, &item, sizeof(item));
memcpy(btrfs_leaf_data(empty_leaf) + btrfs_item_offset(&item),
&extent_item, btrfs_item_size(&item));
ret = pwrite(fd, empty_leaf, blocksize, (start_block + 2) * blocksize);
if (ret != blocksize)
return -1;
/* finally create the FS root */
btrfs_set_header_parentid(&empty_leaf.header, BTRFS_FS_TREE_OBJECTID);
btrfs_set_header_blocknr(&empty_leaf.header, 19);
btrfs_set_header_nritems(&empty_leaf.header, 0);
ret = pwrite(fd, &empty_leaf, blocksize, 19 * blocksize);
if (ret != sizeof(empty_leaf))
btrfs_set_header_parentid(&empty_leaf->header, BTRFS_FS_TREE_OBJECTID);
btrfs_set_header_blocknr(&empty_leaf->header, start_block + 3);
btrfs_set_header_nritems(&empty_leaf->header, 0);
ret = pwrite(fd, empty_leaf, blocksize, (start_block + 3) * blocksize);
if (ret != blocksize)
return -1;
return 0;
}
#if 0
int mkfs(int fd)
{
struct btrfs_root_info info[2];
struct btrfs_leaf empty_leaf;
struct btrfs_item item;
struct btrfs_extent_item extent_item;
int ret;
/* setup the super block area */
memset(info, 0, sizeof(info));
btrfs_set_root_blocknr(info, 16);
btrfs_set_root_objectid(info, 1);
btrfs_set_root_tree_root(info, 17);
btrfs_set_root_blocknr(info + 1, 16);
btrfs_set_root_objectid(info + 1, 2);
btrfs_set_root_tree_root(info + 1, 18);
ret = pwrite(fd, info, sizeof(info),
BTRFS_SUPER_INFO_OFFSET(BTRFS_BLOCKSIZE));
if (ret != sizeof(info))
return -1;
/* create leaves for the tree root and extent root */
memset(&empty_leaf, 0, sizeof(empty_leaf));
btrfs_set_header_parentid(&empty_leaf.header, 1);
btrfs_set_header_blocknr(&empty_leaf.header, 17);
ret = pwrite(fd, &empty_leaf, sizeof(empty_leaf), 17 * BTRFS_BLOCKSIZE);
if (ret != sizeof(empty_leaf))
return -1;
btrfs_set_header_parentid(&empty_leaf.header, 2);
btrfs_set_header_blocknr(&empty_leaf.header, 18);
btrfs_set_header_nritems(&empty_leaf.header, 3);
/* item1, reserve blocks 0-16 */
btrfs_set_key_objectid(&item.key, 0);
btrfs_set_key_offset(&item.key, 17);
btrfs_set_key_flags(&item.key, 0);
btrfs_set_item_offset(&item, LEAF_DATA_SIZE -
sizeof(struct btrfs_extent_item));
btrfs_set_item_size(&item, sizeof(struct btrfs_extent_item));
btrfs_set_extent_refs(&extent_item, 1);
btrfs_set_extent_owner(&extent_item, 0);
memcpy(empty_leaf.items, &item, sizeof(item));
memcpy(empty_leaf.data + btrfs_item_offset(&item), &extent_item,
btrfs_item_size(&item));
/* item2, give block 17 to the root */
btrfs_set_key_objectid(&item.key, 17);
btrfs_set_key_offset(&item.key, 1);
btrfs_set_item_offset(&item, LEAF_DATA_SIZE -
sizeof(struct btrfs_extent_item) * 2);
btrfs_set_extent_owner(&extent_item, 1);
memcpy(empty_leaf.items + 1, &item, sizeof(item));
memcpy(empty_leaf.data + btrfs_item_offset(&item), &extent_item,
btrfs_item_size(&item));
/* item3, give block 18 for the extent root */
btrfs_set_key_objectid(&item.key, 18);
btrfs_set_key_offset(&item.key, 1);
btrfs_set_item_offset(&item, LEAF_DATA_SIZE -
sizeof(struct btrfs_extent_item) * 3);
btrfs_set_extent_owner(&extent_item, 2);
memcpy(empty_leaf.items + 2, &item, sizeof(item));
memcpy(empty_leaf.data + btrfs_item_offset(&item), &extent_item,
btrfs_item_size(&item));
ret = pwrite(fd, &empty_leaf, sizeof(empty_leaf), 18 * BTRFS_BLOCKSIZE);
if (ret != sizeof(empty_leaf))
return -1;
return 0;
}
#endif

15
print-tree.c
View File

@ -5,7 +5,7 @@
#include "ctree.h"
#include "disk-io.h"
void btrfs_print_leaf(struct btrfs_leaf *l)
void btrfs_print_leaf(struct btrfs_root *root, struct btrfs_leaf *l)
{
int i;
u32 nr = btrfs_header_nritems(&l->header);
@ -13,7 +13,8 @@ void btrfs_print_leaf(struct btrfs_leaf *l)
struct btrfs_extent_item *ei;
struct btrfs_root_item *ri;
printf("leaf %Lu total ptrs %d free space %d\n",
btrfs_header_blocknr(&l->header), nr, btrfs_leaf_free_space(l));
btrfs_header_blocknr(&l->header), nr,
btrfs_leaf_free_space(root, l));
fflush(stdout);
for (i = 0 ; i < nr ; i++) {
item = l->items + i;
@ -25,7 +26,7 @@ void btrfs_print_leaf(struct btrfs_leaf *l)
btrfs_item_offset(item),
btrfs_item_size(item));
printf("\t\titem data %.*s\n", btrfs_item_size(item),
l->data + btrfs_item_offset(item));
btrfs_leaf_data(l) + btrfs_item_offset(item));
ei = btrfs_item_ptr(l, i, struct btrfs_extent_item);
printf("\t\textent data refs %u owner %Lu\n",
btrfs_extent_refs(ei), btrfs_extent_owner(ei));
@ -46,18 +47,18 @@ void btrfs_print_tree(struct btrfs_root *root, struct btrfs_buffer *t)
c = &t->node;
nr = btrfs_header_nritems(&c->header);
if (btrfs_is_leaf(c)) {
btrfs_print_leaf((struct btrfs_leaf *)c);
btrfs_print_leaf(root, (struct btrfs_leaf *)c);
return;
}
printf("node %Lu level %d total ptrs %d free spc %u\n", t->blocknr,
btrfs_header_level(&c->header), nr,
(u32)NODEPTRS_PER_BLOCK - nr);
(u32)BTRFS_NODEPTRS_PER_BLOCK(root) - nr);
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,
btrfs_node_blockptr(c, i));
c->ptrs[i].key.objectid, c->ptrs[i].key.flags,
c->ptrs[i].key.offset, btrfs_node_blockptr(c, i));
fflush(stdout);
}
for (i = 0; i < nr; i++) {

2
print-tree.h
View File

@ -1,3 +1,3 @@
void btrfs_print_leaf(struct btrfs_leaf *l);
void btrfs_print_leaf(struct btrfs_root *root, struct btrfs_leaf *l);
void btrfs_print_tree(struct btrfs_root *root, struct btrfs_buffer *t);

2
quick-test.c
View File

@ -73,7 +73,7 @@ int main(int ac, char **av) {
printf("node %p level %d total ptrs %d free spc %lu\n", root->node,
btrfs_header_level(&root->node->node.header),
btrfs_header_nritems(&root->node->node.header),
NODEPTRS_PER_BLOCK -
BTRFS_NODEPTRS_PER_BLOCK(root) -
btrfs_header_nritems(&root->node->node.header));
printf("all searches good, deleting some items\n");
i = 0;

4
root-tree.c
View File

@ -31,7 +31,7 @@ int btrfs_find_last_root(struct btrfs_root *root, u64 objectid,
ret = 1;
goto out;
}
memcpy(item, l->data + btrfs_item_offset(l->items + slot),
memcpy(item, btrfs_item_ptr(l, slot, struct btrfs_root_item),
sizeof(*item));
btrfs_disk_key_to_cpu(key, &l->items[slot].key);
btrfs_release_path(root, &path);
@ -55,7 +55,7 @@ int btrfs_update_root(struct btrfs_root *root, struct btrfs_key *key,
BUG_ON(ret != 0);
l = &path.nodes[0]->leaf;
slot = path.slots[0];
memcpy(l->data + btrfs_item_offset(l->items + slot), item,
memcpy(btrfs_item_ptr(l, slot, struct btrfs_root_item), item,
sizeof(*item));
out:
btrfs_release_path(root, &path);