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#define _XOPEN_SOURCE 500
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include "kerncompat.h"
#include "radix-tree.h"
#include "ctree.h"
#include "disk-io.h"
static int allocated_blocks = 0;
static int get_free_block(struct ctree_root *root, u64 *block)
{
struct stat st;
int ret = 0;
if (root->alloc_extent->num_used >= root->alloc_extent->num_blocks)
return -1;
*block = root->alloc_extent->blocknr + root->alloc_extent->num_used;
root->alloc_extent->num_used += 1;
if (root->alloc_extent->num_used >= root->alloc_extent->num_blocks) {
struct alloc_extent *ae = root->alloc_extent;
root->alloc_extent = root->reserve_extent;
root->reserve_extent = ae;
ae->num_blocks = 0;
}
st.st_size = 0;
ret = fstat(root->fp, &st);
if (st.st_size < (*block + 1) * CTREE_BLOCKSIZE) {
ret = ftruncate(root->fp,
(*block + 1) * CTREE_BLOCKSIZE);
if (ret) {
perror("ftruncate");
exit(1);
}
}
return ret;
}
struct tree_buffer *alloc_tree_block(struct ctree_root *root, u64 blocknr)
{
struct tree_buffer *buf;
int ret;
buf = malloc(sizeof(struct tree_buffer));
if (!buf)
return buf;
allocated_blocks++;
buf->blocknr = blocknr;
buf->count = 1;
radix_tree_preload(GFP_KERNEL);
ret = radix_tree_insert(&root->cache_radix, blocknr, buf);
radix_tree_preload_end();
if (ret) {
free(buf);
return NULL;
}
return buf;
}
struct tree_buffer *alloc_free_block(struct ctree_root *root)
{
u64 free_block;
int ret;
struct tree_buffer * buf;
ret = get_free_block(root, &free_block);
if (ret) {
BUG();
return NULL;
}
buf = alloc_tree_block(root, free_block);
if (!buf)
BUG();
return buf;
}
struct tree_buffer *read_tree_block(struct ctree_root *root, u64 blocknr)
{
loff_t offset = blocknr * CTREE_BLOCKSIZE;
struct tree_buffer *buf;
int ret;
buf = radix_tree_lookup(&root->cache_radix, blocknr);
if (buf) {
buf->count++;
goto test;
}
buf = alloc_tree_block(root, blocknr);
if (!buf)
return NULL;
ret = pread(root->fp, &buf->node, CTREE_BLOCKSIZE, offset);
if (ret != CTREE_BLOCKSIZE) {
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;
}
int write_tree_block(struct ctree_root *root, struct tree_buffer *buf)
{
u64 blocknr = buf->blocknr;
loff_t offset = blocknr * CTREE_BLOCKSIZE;
int ret;
if (buf->blocknr != buf->node.header.blocknr)
BUG();
ret = pwrite(root->fp, &buf->node, CTREE_BLOCKSIZE, offset);
if (ret != CTREE_BLOCKSIZE)
return ret;
return 0;
}
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;
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_super_block *super)
{
struct ctree_root *root = malloc(sizeof(struct ctree_root));
struct ctree_root *extent_root = malloc(sizeof(struct ctree_root));
int fp;
int ret;
fp = open(filename, O_CREAT | O_RDWR);
if (fp < 0) {
free(root);
return NULL;
}
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),
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);
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;
}
void tree_block_release(struct ctree_root *root, struct tree_buffer *buf)
{
buf->count--;
if (buf->count < 0)
BUG();
if (buf->count == 0) {
if (!radix_tree_lookup(&root->cache_radix, buf->blocknr))
BUG();
radix_tree_delete(&root->cache_radix, buf->blocknr);
memset(buf, 0, sizeof(*buf));
free(buf);
BUG_ON(allocated_blocks == 0);
allocated_blocks--;
}
}
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