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Btrfs: extent fixes 

Signed-off-by: Chris Mason <chris.mason@oracle.com>
This commit is contained in:
Chris Mason 2007-02-21 17:04:57 -05:00 committed by David Woodhouse
parent 06ed4b316e
commit cfaa72952f
5 changed files with 103 additions and 61 deletions
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69
fs/btrfs/ctree.c
View File

@ -354,6 +354,7 @@ int __insert_ptr(struct ctree_root *root,
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;
@ -363,7 +364,7 @@ int __insert_ptr(struct ctree_root *root,
memcpy(c->keys + 1, key, sizeof(struct key));
c->blockptrs[0] = path->nodes[level-1]->blocknr;
c->blockptrs[1] = blocknr;
/* the path has an extra ref to root->node */
/* the super has an extra ref to root->node */
tree_block_release(root, root->node);
root->node = t;
t->count++;
@ -439,6 +440,7 @@ int insert_ptr(struct ctree_root *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));
@ -642,6 +644,7 @@ int split_leaf(struct ctree_root *root, struct ctree_path *path, int data_size)
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,
@ -689,8 +692,12 @@ int insert_item(struct ctree_root *root, struct key *key,
unsigned int data_end;
struct ctree_path path;
refill_alloc_extent(root);
/* create a root if there isn't one */
if (!root->node) {
BUG();
#if 0
struct tree_buffer *t;
t = alloc_free_block(root);
BUG_ON(!t);
@ -699,6 +706,7 @@ int insert_item(struct ctree_root *root, struct key *key,
t->node.header.blocknr = t->blocknr;
root->node = t;
write_tree_block(root, t);
#endif
}
init_path(&path);
ret = search_slot(root, key, &path);
@ -758,7 +766,6 @@ int insert_item(struct ctree_root *root, struct key *key,
if (leaf_free_space(leaf) < 0)
BUG();
release_path(root, &path);
refill_alloc_extent(root);
return 0;
}
@ -893,7 +900,7 @@ int next_leaf(struct ctree_root *root, struct ctree_path *path)
int level = 1;
u64 blocknr;
struct tree_buffer *c;
struct tree_buffer *next;
struct tree_buffer *next = NULL;
while(level < MAX_LEVEL) {
if (!path->nodes[level])
@ -905,6 +912,8 @@ int next_leaf(struct ctree_root *root, struct ctree_path *path)
continue;
}
blocknr = c->node.blockptrs[slot];
if (next)
tree_block_release(root, next);
next = read_tree_block(root, blocknr);
break;
}
@ -922,7 +931,7 @@ int next_leaf(struct ctree_root *root, struct ctree_path *path)
return 0;
}
int alloc_extent(struct ctree_root *root, u64 num_blocks, u64 search_start,
int alloc_extent(struct ctree_root *orig_root, u64 num_blocks, u64 search_start,
u64 search_end, u64 owner, struct key *ins)
{
struct ctree_path path;
@ -934,6 +943,7 @@ int alloc_extent(struct ctree_root *root, u64 num_blocks, u64 search_start,
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;
@ -974,13 +984,18 @@ int alloc_extent(struct ctree_root *root, u64 num_blocks, u64 search_start,
start_found = 1;
last_block = key->objectid + key->offset;
path.slots[0]++;
printf("last block is not %lu\n", last_block);
}
// FIXME -ENOSPC
insert:
release_path(root, &path);
extent_item.refs = 1;
extent_item.owner = owner;
ret = insert_item(root, ins, &extent_item, sizeof(extent_item));
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;
}
@ -991,7 +1006,6 @@ static int refill_alloc_extent(struct ctree_root *root)
int ret;
int min_blocks = MAX_LEVEL * 2;
printf("refill alloc root %p, numused %lu total %lu\n", root, ae->num_used, ae->num_blocks);
if (ae->num_blocks > ae->num_used && ae->num_blocks - ae->num_used >
min_blocks)
return 0;
@ -1007,9 +1021,9 @@ static int refill_alloc_extent(struct ctree_root *root)
BUG();
return 0;
}
// FIXME, this recurses
ret = alloc_extent(root->extent_root,
min_blocks * 2, 0, (unsigned long)-1, 0, &key);
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;
@ -1021,6 +1035,7 @@ 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);
@ -1032,6 +1047,8 @@ void print_leaf(struct leaf *l)
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);
}
}
@ -1080,8 +1097,8 @@ void print_tree(struct ctree_root *root, struct tree_buffer *t)
/* 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() {
@ -1092,15 +1109,20 @@ int main() {
int i;
int num;
int ret;
int run_size = 256;
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");
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++) {
@ -1112,22 +1134,20 @@ int main() {
ins.objectid = num;
ins.offset = 0;
ins.flags = 0;
printf("insert %d\n", i);
ret = insert_item(root, &ins, buf, strlen(buf));
if (!ret)
tree_size++;
printf("done insert %d\n", i);
}
printf("root used: %lu\n", root->alloc_extent->num_used);
printf("root tree\n");
print_tree(root, root->node);
// 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);
exit(1);
// print_tree(root->extent_root, root->extent_root->node);
write_ctree_super(root, &super);
close_ctree(root);
root = open_ctree("dbfile");
root = open_ctree("dbfile", &super);
printf("starting search\n");
srand(55);
for (i = 0; i < run_size; i++) {
@ -1142,8 +1162,9 @@ int main() {
}
release_path(root, &path);
}
write_ctree_super(root, &super);
close_ctree(root);
root = open_ctree("dbfile");
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,
@ -1174,8 +1195,9 @@ int main() {
if (!ret)
tree_size++;
}
write_ctree_super(root, &super);
close_ctree(root);
root = open_ctree("dbfile");
root = open_ctree("dbfile", &super);
printf("starting search2\n");
srand(128);
for (i = 0; i < run_size; i++) {
@ -1221,6 +1243,7 @@ int main() {
}
release_path(root, &path);
}
write_ctree_super(root, &super);
close_ctree(root);
printf("tree size is now %d\n", tree_size);
return 0;

5
fs/btrfs/ctree.h
View File

@ -57,6 +57,11 @@ struct ctree_root_info {
u64 snapuuid[2]; /* root specific uuid */
} __attribute__ ((__packed__));
struct ctree_super_block {
struct ctree_root_info root_info;
struct ctree_root_info extent_info;
} __attribute__ ((__packed__));
struct item {
struct key key;
u16 offset;

79
fs/btrfs/disk-io.c
View File

@ -15,7 +15,7 @@ static int allocated_blocks = 0;
static int get_free_block(struct ctree_root *root, u64 *block)
{
struct stat st;
int ret;
int ret = 0;
if (root->alloc_extent->num_used >= root->alloc_extent->num_blocks)
return -1;
@ -30,9 +30,14 @@ static int get_free_block(struct ctree_root *root, u64 *block)
}
st.st_size = 0;
ret = fstat(root->fp, &st);
if (st.st_size < (*block + 1) * CTREE_BLOCKSIZE)
if (st.st_size < (*block + 1) * CTREE_BLOCKSIZE) {
ret = ftruncate(root->fp,
(*block + 1) * CTREE_BLOCKSIZE);
if (ret) {
perror("ftruncate");
exit(1);
}
}
return ret;
}
@ -81,11 +86,7 @@ struct tree_buffer *read_tree_block(struct ctree_root *root, u64 blocknr)
buf = radix_tree_lookup(&root->cache_radix, blocknr);
if (buf) {
buf->count++;
if (buf->blocknr != blocknr)
BUG();
if (buf->blocknr != buf->node.header.blocknr)
BUG();
return buf;
goto test;
}
buf = alloc_tree_block(root, blocknr);
if (!buf)
@ -95,8 +96,11 @@ struct tree_buffer *read_tree_block(struct ctree_root *root, u64 blocknr)
free(buf);
return NULL;
}
test:
if (buf->blocknr != buf->node.header.blocknr)
BUG();
if (root->node && buf->node.header.parentid != root->node->node.header.parentid)
BUG();
return buf;
}
@ -111,36 +115,30 @@ int write_tree_block(struct ctree_root *root, struct tree_buffer *buf)
ret = pwrite(root->fp, &buf->node, CTREE_BLOCKSIZE, offset);
if (ret != CTREE_BLOCKSIZE)
return ret;
if (buf == root->node)
return update_root_block(root);
return 0;
}
struct ctree_super_block {
struct ctree_root_info root_info;
struct ctree_root_info extent_info;
} __attribute__ ((__packed__));
static int __setup_root(struct ctree_root *root, struct ctree_root *extent_root,
struct ctree_root_info *info, int fp)
{
INIT_RADIX_TREE(&root->cache_radix, GFP_KERNEL);
root->fp = fp;
root->node = NULL;
root->node = read_tree_block(root, info->tree_root);
root->extent_root = extent_root;
memcpy(&root->ai1, &info->alloc_extent, sizeof(info->alloc_extent));
memcpy(&root->ai2, &info->reserve_extent, sizeof(info->reserve_extent));
root->alloc_extent = &root->ai1;
root->reserve_extent = &root->ai2;
INIT_RADIX_TREE(&root->cache_radix, GFP_KERNEL);
printf("setup done reading root %p, used %lu\n", root, root->alloc_extent->num_used);
printf("setup done reading root %p, used %lu available %lu\n", root, root->alloc_extent->num_used, root->alloc_extent->num_blocks);
printf("setup done reading root %p, reserve used %lu available %lu\n", root, root->reserve_extent->num_used, root->reserve_extent->num_blocks);
return 0;
}
struct ctree_root *open_ctree(char *filename)
struct ctree_root *open_ctree(char *filename, struct ctree_super_block *super)
{
struct ctree_root *root = malloc(sizeof(struct ctree_root));
struct ctree_root *extent_root = malloc(sizeof(struct ctree_root));
struct ctree_super_block super;
int fp;
int ret;
@ -149,48 +147,61 @@ struct ctree_root *open_ctree(char *filename)
free(root);
return NULL;
}
ret = pread(fp, &super, sizeof(struct ctree_super_block),
ret = pread(fp, super, sizeof(struct ctree_super_block),
CTREE_SUPER_INFO_OFFSET(CTREE_BLOCKSIZE));
if (ret == 0) {
ret = mkfs(fp);
if (ret)
return NULL;
ret = pread(fp, &super, sizeof(struct ctree_super_block),
ret = pread(fp, super, sizeof(struct ctree_super_block),
CTREE_SUPER_INFO_OFFSET(CTREE_BLOCKSIZE));
if (ret != sizeof(struct ctree_super_block))
return NULL;
}
BUG_ON(ret < 0);
__setup_root(root, extent_root, &super.root_info, fp);
__setup_root(extent_root, extent_root, &super.extent_info, fp);
__setup_root(root, extent_root, &super->root_info, fp);
__setup_root(extent_root, extent_root, &super->extent_info, fp);
return root;
}
static int __update_root(struct ctree_root *root, struct ctree_root_info *info)
{
info->tree_root = root->node->blocknr;
memcpy(&info->alloc_extent, root->alloc_extent, sizeof(struct alloc_extent));
memcpy(&info->reserve_extent, root->reserve_extent, sizeof(struct alloc_extent));
return 0;
}
int write_ctree_super(struct ctree_root *root, struct ctree_super_block *s)
{
int ret;
__update_root(root, &s->root_info);
__update_root(root->extent_root, &s->extent_info);
ret = pwrite(root->fp, s, sizeof(*s), CTREE_SUPER_INFO_OFFSET(CTREE_BLOCKSIZE));
if (ret != sizeof(*s)) {
fprintf(stderr, "failed to write new super block err %d\n", ret);
return ret;
}
return 0;
}
int close_ctree(struct ctree_root *root)
{
close(root->fp);
if (root->node)
tree_block_release(root, root->node);
if (root->extent_root->node)
tree_block_release(root->extent_root, root->extent_root->node);
free(root);
printf("on close %d blocks are allocated\n", allocated_blocks);
return 0;
}
int update_root_block(struct ctree_root *root)
{
int ret;
u64 root_block = root->node->blocknr;
ret = pwrite(root->fp, &root_block, sizeof(u64), 0);
if (ret != sizeof(u64))
return ret;
return 0;
}
void tree_block_release(struct ctree_root *root, struct tree_buffer *buf)
{
return;
buf->count--;
if (buf->count < 0)
BUG();
if (buf->count == 0) {
if (!radix_tree_lookup(&root->cache_radix, buf->blocknr))
BUG();

4
fs/btrfs/disk-io.h
View File

@ -12,11 +12,11 @@ struct tree_buffer {
struct tree_buffer *read_tree_block(struct ctree_root *root, u64 blocknr);
int write_tree_block(struct ctree_root *root, struct tree_buffer *buf);
struct ctree_root *open_ctree(char *filename);
struct ctree_root *open_ctree(char *filename, struct ctree_super_block *s);
int close_ctree(struct ctree_root *root);
void tree_block_release(struct ctree_root *root, struct tree_buffer *buf);
struct tree_buffer *alloc_free_block(struct ctree_root *root);
int update_root_block(struct ctree_root *root);
int write_ctree_super(struct ctree_root *root, struct ctree_super_block *s);
int mkfs(int fd);
#define CTREE_SUPER_INFO_OFFSET(bs) (16 * (bs))

7
fs/btrfs/mkfs.c
View File

@ -18,12 +18,13 @@ int mkfs(int fd)
struct extent_item extent_item;
int ret;
/* setup the super block area */
memset(info, 0, sizeof(info));
info[0].blocknr = 16;
info[0].objectid = 1;
info[0].tree_root = 17;
info[0].alloc_extent.blocknr = 0;
info[0].alloc_extent.num_blocks = 20;
info[0].alloc_extent.num_blocks = 64;
/* 0-17 are used (inclusive) */
info[0].alloc_extent.num_used = 18;
@ -31,12 +32,14 @@ int mkfs(int fd)
info[1].objectid = 2;
info[1].tree_root = 64;
info[1].alloc_extent.blocknr = 64;
info[1].alloc_extent.num_blocks = 8;
info[1].alloc_extent.num_blocks = 64;
info[1].alloc_extent.num_used = 1;
ret = pwrite(fd, info, sizeof(info),
CTREE_SUPER_INFO_OFFSET(CTREE_BLOCKSIZE));
if (ret != sizeof(info))
return -1;
/* create leaves for the tree root and extent root */
memset(&empty_leaf, 0, sizeof(empty_leaf));
empty_leaf.header.parentid = 1;
empty_leaf.header.blocknr = 17;