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Btrfs: Break up ctree.c a little 

Extent fixes

Signed-off-by: Chris Mason <chris.mason@oracle.com>
This commit is contained in:
Chris Mason 2007-02-24 06:24:44 -05:00 committed by David Woodhouse
parent 9a8dd1502d
commit 5de08d7d50
6 changed files with 176 additions and 374 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
fs/btrfs/Makefile
View File

@ -1,12 +1,16 @@
CFLAGS= -g -Wall
CFLAGS = -g -Wall
headers = radix-tree.h ctree.h disk-io.h kerncompat.h print-tree.h
objects = ctree.o disk-io.o radix-tree.o mkfs.o extent-tree.o print-tree.o
.c.o:
$(CC) $(CFLAGS) -c $<
#.c.o:
# $(CC) $(CFLAGS) -c $<
ctree: ctree.o disk-io.h ctree.h disk-io.o radix-tree.o radix-tree.h mkfs.o
gcc $(CFLAGS) -o ctree ctree.o disk-io.o radix-tree.o mkfs.o
ctree : $(objects)
gcc $(CFLAGS) -o ctree $(objects)
clean:
$(objects) : $(headers)
clean :
rm ctree *.o

446
fs/btrfs/ctree.c
View File

@ -4,23 +4,21 @@
#include "radix-tree.h"
#include "ctree.h"
#include "disk-io.h"
#define SEARCH_READ 0
#define SEARCH_WRITE 1
#define CTREE_EXTENT_PENDING 0
#include "print-tree.h"
int split_node(struct ctree_root *root, struct ctree_path *path, int level);
int split_leaf(struct ctree_root *root, struct ctree_path *path, int data_size);
struct tree_buffer *alloc_free_block(struct ctree_root *root);
int free_extent(struct ctree_root *root, u64 blocknr, u64 num_blocks);
int push_node_left(struct ctree_root *root, struct ctree_path *path, int level);
int push_node_right(struct ctree_root *root,
struct ctree_path *path, int level);
int del_ptr(struct ctree_root *root, struct ctree_path *path, int level);
static inline void init_path(struct ctree_path *p)
inline void init_path(struct ctree_path *p)
{
memset(p, 0, sizeof(*p));
}
static void release_path(struct ctree_root *root, struct ctree_path *p)
void release_path(struct ctree_root *root, struct ctree_path *p)
{
int i;
for (i = 0; i < MAX_LEVEL; i++) {
@ -48,7 +46,7 @@ static inline unsigned int leaf_data_end(struct leaf *leaf)
* 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 leaf_free_space(struct leaf *leaf)
{
int data_end = leaf_data_end(leaf);
int nritems = leaf->header.nritems;
@ -133,7 +131,8 @@ int bin_search(struct node *c, struct key *key, int *slot)
* If the key isn't found, the path points to the slot where it should
* be inserted.
*/
int search_slot(struct ctree_root *root, struct key *key, struct ctree_path *p, int ins_len)
int search_slot(struct ctree_root *root, struct key *key,
struct ctree_path *p, int ins_len)
{
struct tree_buffer *b = root->node;
struct node *c;
@ -151,7 +150,8 @@ int search_slot(struct ctree_root *root, struct key *key, struct ctree_path *p,
if (ret && slot > 0)
slot -= 1;
p->slots[level] = slot;
if (ins_len && c->header.nritems == NODEPTRS_PER_BLOCK) {
if (ins_len > 0 &&
c->header.nritems == NODEPTRS_PER_BLOCK) {
int sret = split_node(root, p, level);
BUG_ON(sret > 0);
if (sret)
@ -159,13 +159,37 @@ int search_slot(struct ctree_root *root, struct key *key, struct ctree_path *p,
b = p->nodes[level];
c = &b->node;
slot = p->slots[level];
} else if (ins_len < 0 &&
c->header.nritems <= NODEPTRS_PER_BLOCK/4) {
u64 blocknr = b->blocknr;
slot = p->slots[level +1];
b->count++;
if (push_node_left(root, p, level))
push_node_right(root, p, level);
if (c->header.nritems == 0 &&
level < MAX_LEVEL - 1 &&
p->nodes[level + 1]) {
int tslot = p->slots[level + 1];
p->slots[level + 1] = slot;
del_ptr(root, p, level + 1);
p->slots[level + 1] = tslot;
tree_block_release(root, b);
free_extent(root, blocknr, 1);
} else {
tree_block_release(root, b);
}
b = p->nodes[level];
c = &b->node;
slot = p->slots[level];
}
b = read_tree_block(root, c->blockptrs[slot]);
continue;
} else {
struct leaf *l = (struct leaf *)c;
p->slots[level] = slot;
if (ins_len && leaf_free_space(l) < sizeof(struct item) + ins_len) {
if (ins_len > 0 && leaf_free_space(l) <
sizeof(struct item) + ins_len) {
int sret = split_leaf(root, p, ins_len);
BUG_ON(sret > 0);
if (sret)
@ -355,7 +379,8 @@ int push_node_right(struct ctree_root *root, struct ctree_path *path, int level)
return 0;
}
static int insert_new_root(struct ctree_root *root, struct ctree_path *path, int level)
static int insert_new_root(struct ctree_root *root,
struct ctree_path *path, int level)
{
struct tree_buffer *t;
struct node *lower;
@ -463,7 +488,7 @@ int split_node(struct ctree_root *root, struct ctree_path *path, int level)
write_tree_block(root, split_buffer);
insert_ptr(root, path, split->keys, split_buffer->blocknr,
path->slots[level + 1] + 1, level + 1);
if (path->slots[level] > mid) {
if (path->slots[level] >= mid) {
path->slots[level] -= mid;
tree_block_release(root, t);
path->nodes[level] = split_buffer;
@ -744,8 +769,7 @@ int insert_item(struct ctree_root *root, struct key *key,
}
/*
* 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
@ -778,22 +802,10 @@ int del_ptr(struct ctree_root *root, struct ctree_path *path, int level)
write_tree_block(root, t);
blocknr = t->blocknr;
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;
break;
}
if (t == root->node) {
/* just turn the root into a leaf and break */
@ -850,12 +862,12 @@ int del_item(struct ctree_root *root, struct ctree_path *path)
free_extent(root, leaf_buf->blocknr, 1);
}
} else {
int used = leaf_space_used(leaf, 0, leaf->header.nritems);
if (slot == 0)
fixup_low_keys(root, path, &leaf->items[0].key, 1);
write_tree_block(root, leaf_buf);
/* delete the leaf if it is mostly empty */
if (leaf_space_used(leaf, 0, leaf->header.nritems) <
LEAF_DATA_SIZE / 4) {
if (used < LEAF_DATA_SIZE / 3) {
/* push_leaf_left fixes the path.
* make sure the path still points to our leaf
* for possible call to del_ptr below
@ -864,81 +876,19 @@ int del_item(struct ctree_root *root, struct ctree_path *path)
leaf_buf->count++;
push_leaf_left(root, path, 1);
if (leaf->header.nritems == 0) {
u64 blocknr = leaf_buf->blocknr;
path->slots[1] = slot;
del_ptr(root, path, 1);
tree_block_release(root, leaf_buf);
free_extent(root, blocknr, 1);
} else {
tree_block_release(root, leaf_buf);
}
tree_block_release(root, leaf_buf);
}
}
return 0;
}
static int del_pending_extents(struct ctree_root *extent_root)
{
int ret;
struct key key;
struct tree_buffer *gang[4];
int i;
struct ctree_path path;
while(1) {
ret = radix_tree_gang_lookup_tag(&extent_root->cache_radix,
(void **)gang, 0, ARRAY_SIZE(gang),
CTREE_EXTENT_PENDING);
if (!ret)
break;
for (i = 0; i < ret; i++) {
key.objectid = gang[i]->blocknr;
key.flags = 0;
key.offset = 1;
init_path(&path);
ret = search_slot(extent_root, &key, &path, 0);
if (ret) {
BUG();
// FIXME undo it and return sane
return ret;
}
ret = del_item(extent_root, &path);
if (ret) {
BUG();
return ret;
}
release_path(extent_root, &path);
radix_tree_tag_clear(&extent_root->cache_radix, gang[i]->blocknr,
CTREE_EXTENT_PENDING);
tree_block_release(extent_root, gang[i]);
}
}
return 0;
}
int free_extent(struct ctree_root *root, u64 blocknr, u64 num_blocks)
{
struct ctree_path path;
struct key key;
struct ctree_root *extent_root = root->extent_root;
struct tree_buffer *t;
int pending_ret;
int ret;
key.objectid = blocknr;
key.flags = 0;
key.offset = num_blocks;
if (root == extent_root) {
t = read_tree_block(root, key.objectid);
radix_tree_tag_set(&root->cache_radix, key.objectid, CTREE_EXTENT_PENDING);
return 0;
}
init_path(&path);
ret = search_slot(extent_root, &key, &path, 0);
if (ret)
BUG();
ret = del_item(extent_root, &path);
release_path(extent_root, &path);
pending_ret = del_pending_extents(root->extent_root);
return ret ? ret : pending_ret;
}
int next_leaf(struct ctree_root *root, struct ctree_path *path)
{
int slot;
@ -976,241 +926,10 @@ int next_leaf(struct ctree_root *root, struct ctree_path *path)
return 0;
}
int find_free_extent(struct ctree_root *orig_root, u64 num_blocks, u64 search_start,
u64 search_end, struct key *ins)
{
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 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, 0);
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;
start_found = 1;
goto insert;
}
ins->objectid = last_block;
ins->offset = num_blocks;
hole_size = search_end - last_block;
goto insert;
}
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;
insert_failed:
path.slots[0]++;
}
// FIXME -ENOSPC
insert:
if (orig_root->extent_root == orig_root) {
BUG_ON(num_blocks != 1);
if ((root->current_insert.objectid <= ins->objectid &&
root->current_insert.objectid + root->current_insert.offset >
ins->objectid) ||
(root->current_insert.objectid > ins->objectid &&
root->current_insert.objectid <= ins->objectid + ins->offset) ||
radix_tree_tag_get(&root->cache_radix, ins->objectid,
CTREE_EXTENT_PENDING)) {
last_block = ins->objectid + 1;
search_start = last_block;
goto insert_failed;
}
}
release_path(root, &path);
if (ins->offset != 1)
BUG();
return 0;
}
static int insert_pending_extents(struct ctree_root *extent_root)
{
int ret;
struct key key;
struct extent_item item;
struct tree_buffer *gang[4];
int i;
// FIXME -ENOSPC
item.refs = 1;
item.owner = extent_root->node->node.header.parentid;
while(1) {
ret = radix_tree_gang_lookup_tag(&extent_root->cache_radix,
(void **)gang, 0, ARRAY_SIZE(gang),
CTREE_EXTENT_PENDING);
if (!ret)
break;
for (i = 0; i < ret; i++) {
key.objectid = gang[i]->blocknr;
key.flags = 0;
key.offset = 1;
ret = insert_item(extent_root, &key, &item, sizeof(item));
if (ret) {
BUG();
// FIXME undo it and return sane
return ret;
}
radix_tree_tag_clear(&extent_root->cache_radix, gang[i]->blocknr,
CTREE_EXTENT_PENDING);
tree_block_release(extent_root, gang[i]);
}
}
return 0;
}
int alloc_extent(struct ctree_root *root, u64 num_blocks, u64 search_start,
u64 search_end, u64 owner, struct key *ins, struct tree_buffer **buf)
{
int ret;
int pending_ret;
struct extent_item extent_item;
extent_item.refs = 1;
extent_item.owner = owner;
ret = find_free_extent(root, num_blocks, search_start, search_end, ins);
if (ret)
return ret;
if (root != root->extent_root) {
memcpy(&root->extent_root->current_insert, ins, sizeof(*ins));
ret = insert_item(root->extent_root, ins, &extent_item, sizeof(extent_item));
memset(&root->extent_root->current_insert, 0, sizeof(struct key));
pending_ret = insert_pending_extents(root->extent_root);
if (ret)
return ret;
if (pending_ret)
return pending_ret;
*buf = find_tree_block(root, ins->objectid);
return 0;
}
/* we're allocating an extent for the extent tree, don't recurse */
BUG_ON(ins->offset != 1);
*buf = find_tree_block(root, ins->objectid);
BUG_ON(!*buf);
radix_tree_tag_set(&root->cache_radix, ins->objectid, CTREE_EXTENT_PENDING);
(*buf)->count++;
return 0;
}
struct tree_buffer *alloc_free_block(struct ctree_root *root)
{
struct key ins;
int ret;
struct tree_buffer *buf = NULL;
ret = alloc_extent(root, 1, 0, (unsigned long)-1, root->node->node.header.parentid,
&ins, &buf);
if (ret) {
BUG();
return NULL;
}
if (root != root->extent_root)
BUG_ON(radix_tree_tag_get(&root->extent_root->cache_radix, buf->blocknr,
CTREE_EXTENT_PENDING));
return buf;
}
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)
{
int i;
int nr;
struct node *c;
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);
}
}
/* for testing only */
int next_key(int i, int max_key) {
// return rand() % max_key;
return i;
return rand() % max_key;
// return i;
}
int main() {
@ -1221,8 +940,8 @@ int main() {
int i;
int num;
int ret;
int run_size = 10000;
int max_key = 100000000;
int run_size = 20000000;
int max_key = 100000000;
int tree_size = 0;
struct ctree_path path;
struct ctree_super_block super;
@ -1231,11 +950,6 @@ int main() {
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);
fflush(stdout);
srand(55);
for (i = 0; i < run_size; i++) {
@ -1243,13 +957,15 @@ int main() {
num = next_key(i, max_key);
// num = i;
sprintf(buf, "string-%d", num);
// printf("insert %d\n", num);
if (i % 10000 == 0)
printf("insert %d:%d\n", num, i);
ins.objectid = num;
ins.offset = 0;
ins.flags = 0;
ret = insert_item(root, &ins, buf, strlen(buf));
if (!ret)
tree_size++;
free(buf);
}
write_ctree_super(root, &super);
close_ctree(root);
@ -1261,6 +977,8 @@ int main() {
num = next_key(i, max_key);
ins.objectid = num;
init_path(&path);
if (i % 10000 == 0)
printf("search %d:%d\n", num, i);
ret = search_slot(root, &ins, &path, 0);
if (ret) {
print_tree(root, root->node);
@ -1283,39 +1001,32 @@ int main() {
num = next_key(i, max_key);
ins.objectid = num;
init_path(&path);
ret = search_slot(root, &ins, &path, 0);
if (ret)
continue;
ret = del_item(root, &path);
if (ret != 0)
BUG();
ret = search_slot(root, &ins, &path, -1);
if (!ret) {
if (i % 10000 == 0)
printf("del %d:%d\n", num, i);
ret = del_item(root, &path);
if (ret != 0)
BUG();
tree_size--;
}
release_path(root, &path);
tree_size--;
}
write_ctree_super(root, &super);
close_ctree(root);
root = open_ctree("dbfile", &super);
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;
if (i % 10000 == 0)
printf("insert %d:%d\n", num, i);
ret = insert_item(root, &ins, buf, strlen(buf));
if (!ret)
tree_size++;
if (i >= 5) {
struct key ugh;
ugh.objectid = 5;
ugh.flags = 0;
ugh.offset = 0;
init_path(&path);
ret = search_slot(root, &ugh, &path, 0);
if (ret) {
print_tree(root, root->node);
printf("unable to find 5 %d\n", num);
exit(1);
}
release_path(root, &path);
}
free(buf);
}
write_ctree_super(root, &super);
close_ctree(root);
@ -1326,6 +1037,8 @@ int main() {
num = next_key(i, max_key);
ins.objectid = num;
init_path(&path);
if (i % 10000 == 0)
printf("search %d:%d\n", num, i);
ret = search_slot(root, &ins, &path, 0);
if (ret) {
print_tree(root, root->node);
@ -1340,7 +1053,7 @@ int main() {
int slot;
ins.objectid = (u64)-1;
init_path(&path);
ret = search_slot(root, &ins, &path, 0);
ret = search_slot(root, &ins, &path, -1);
if (ret == 0)
BUG();
@ -1356,6 +1069,8 @@ int main() {
if (comp_keys(&last, &leaf->items[slot].key) <= 0)
BUG();
memcpy(&last, &leaf->items[slot].key, sizeof(last));
if (tree_size % 10000 == 0)
printf("big del %d:%d\n", tree_size, i);
ret = del_item(root, &path);
if (ret != 0) {
printf("del_item returned %d\n", ret);
@ -1365,10 +1080,9 @@ int main() {
}
release_path(root, &path);
}
write_ctree_super(root, &super);
close_ctree(root);
printf("tree size is now %d\n", tree_size);
printf("map tree\n");
print_tree(root->extent_root, root->extent_root->node);
write_ctree_super(root, &super);
close_ctree(root);
return 0;
}

12
fs/btrfs/ctree.h
View File

@ -1,7 +1,7 @@
#ifndef __CTREE__
#define __CTREE__
#define CTREE_BLOCKSIZE 256
#define CTREE_BLOCKSIZE 4096
struct key {
u64 objectid;
@ -81,4 +81,14 @@ struct ctree_path {
struct tree_buffer *nodes[MAX_LEVEL];
int slots[MAX_LEVEL];
};
struct tree_buffer *alloc_free_block(struct ctree_root *root);
int free_extent(struct ctree_root *root, u64 blocknr, u64 num_blocks);
int search_slot(struct ctree_root *root, struct key *key, struct ctree_path *p, int ins_len);
void release_path(struct ctree_root *root, struct ctree_path *p);
void init_path(struct ctree_path *p);
int del_item(struct ctree_root *root, struct ctree_path *path);
int insert_item(struct ctree_root *root, struct key *key, void *data, int data_size);
int next_leaf(struct ctree_root *root, struct ctree_path *path);
int leaf_free_space(struct leaf *leaf);
#endif

1
fs/btrfs/disk-io.c
View File

@ -172,7 +172,6 @@ int close_ctree(struct ctree_root *root)
void tree_block_release(struct ctree_root *root, struct tree_buffer *buf)
{
buf->count--;
write_tree_block(root, buf);
if (buf->count < 0)
BUG();
if (buf->count == 0) {

72
fs/btrfs/print-tree.c Normal file
View File

@ -0,0 +1,72 @@
#include <stdio.h>
#include <stdlib.h>
#include "kerncompat.h"
#include "radix-tree.h"
#include "ctree.h"
#include "disk-io.h"
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)
{
int i;
int nr;
struct node *c;
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);
}
}

3
fs/btrfs/print-tree.h Normal file
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@ -0,0 +1,3 @@
void print_leaf(struct leaf *l);
void print_tree(struct ctree_root *root, struct tree_buffer *t);