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Btrfs: add disk ioctl, mostly working

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Signed-off-by: Chris Mason <chris.mason@oracle.com>
This commit is contained in:
Chris Mason
2007-04-12 10:43:05 -04:00
committed by David Woodhouse
parent 7eccb903a8
commit 8352d8a473
5 changed files with 221 additions and 17 deletions
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128
fs/btrfs/disk-io.c
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@@ -16,6 +16,28 @@ struct dev_lookup {
struct block_device *bdev;
};
int btrfs_insert_dev_radix(struct btrfs_root *root,
struct block_device *bdev,
u64 block_start,
u64 num_blocks)
{
struct dev_lookup *lookup;
char b[BDEVNAME_SIZE];
int ret;
lookup = kmalloc(sizeof(*lookup), GFP_NOFS);
if (!lookup)
return -ENOMEM;
lookup->block_start = block_start;
lookup->num_blocks = num_blocks;
lookup->bdev = bdev;
printk("inserting %s into dev radix %Lu %Lu\n", bdevname(bdev, b), block_start, num_blocks);
ret = radix_tree_insert(&root->fs_info->dev_radix, block_start +
num_blocks - 1, lookup);
return ret;
}
u64 bh_blocknr(struct buffer_head *bh)
{
int blkbits = bh->b_page->mapping->host->i_blkbits;
@@ -34,6 +56,8 @@ static int check_tree_block(struct btrfs_root *root, struct buffer_head *buf)
{
struct btrfs_node *node = btrfs_buffer_node(buf);
if (bh_blocknr(buf) != btrfs_header_blocknr(&node->header)) {
printk(KERN_CRIT "bh_blocknr(buf) is %Lu, header is %Lu\n",
bh_blocknr(buf), btrfs_header_blocknr(&node->header));
BUG();
}
return 0;
@@ -76,11 +100,10 @@ out_unlock:
return ret;
}
static int map_bh_to_logical(struct btrfs_root *root, struct buffer_head *bh,
int btrfs_map_bh_to_logical(struct btrfs_root *root, struct buffer_head *bh,
u64 logical)
{
struct dev_lookup *lookup[2];
char b[BDEVNAME_SIZE];
int ret;
@@ -96,7 +119,6 @@ static int map_bh_to_logical(struct btrfs_root *root, struct buffer_head *bh,
}
bh->b_bdev = lookup[0]->bdev;
bh->b_blocknr = logical - lookup[0]->block_start;
printk("logical mapping %Lu to %lu bdev %s\n", logical, bh->b_blocknr, bdevname(bh->b_bdev, b));
set_buffer_mapped(bh);
ret = 0;
out:
@@ -126,7 +148,7 @@ struct buffer_head *btrfs_find_create_tree_block(struct btrfs_root *root,
bh = head;
do {
if (!buffer_mapped(bh)) {
err = map_bh_to_logical(root, bh, first_block);
err = btrfs_map_bh_to_logical(root, bh, first_block);
BUG_ON(err);
}
if (bh_blocknr(bh) == blocknr) {
@@ -150,7 +172,7 @@ static int btree_get_block(struct inode *inode, sector_t iblock,
{
int err;
struct btrfs_root *root = BTRFS_I(bh->b_page->mapping->host)->root;
err = map_bh_to_logical(root, bh, iblock);
err = btrfs_map_bh_to_logical(root, bh, iblock);
return err;
}
@@ -396,6 +418,89 @@ printk("all worked\n");
return root;
}
int btrfs_open_disk(struct btrfs_root *root, u64 block_start, u64 num_blocks,
char *filename, int name_len)
{
char *null_filename;
struct block_device *bdev;
int ret;
if (block_start == 0) {
printk("skipping disk with block_start == 0\n");
return 0;
}
null_filename = kmalloc(name_len + 1, GFP_NOFS);
if (!null_filename)
return -ENOMEM;
memcpy(null_filename, filename, name_len);
null_filename[name_len] = '\0';
bdev = open_bdev_excl(null_filename, O_RDWR, root->fs_info->sb);
if (IS_ERR(bdev)) {
ret = PTR_ERR(bdev);
goto out;
}
set_blocksize(bdev, root->fs_info->sb->s_blocksize);
ret = btrfs_insert_dev_radix(root, bdev, block_start, num_blocks);
BUG_ON(ret);
ret = 0;
out:
kfree(null_filename);
return ret;
}
static int read_device_info(struct btrfs_root *root)
{
struct btrfs_path *path;
int ret;
struct btrfs_key key;
struct btrfs_leaf *leaf;
struct btrfs_device_item *dev_item;
int nritems;
int slot;
root = root->fs_info->dev_root;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = 0;
key.offset = 0;
key.flags = 0;
btrfs_set_key_type(&key, BTRFS_DEV_ITEM_KEY);
mutex_lock(&root->fs_info->fs_mutex);
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
leaf = btrfs_buffer_leaf(path->nodes[0]);
nritems = btrfs_header_nritems(&leaf->header);
while(1) {
slot = path->slots[0];
if (slot >= nritems) {
ret = btrfs_next_leaf(root, path);
if (ret)
break;
leaf = btrfs_buffer_leaf(path->nodes[0]);
nritems = btrfs_header_nritems(&leaf->header);
slot = path->slots[0];
}
btrfs_disk_key_to_cpu(&key, &leaf->items[slot].key);
if (btrfs_key_type(&key) != BTRFS_DEV_ITEM_KEY) {
path->slots[0]++;
continue;
}
dev_item = btrfs_item_ptr(leaf, slot, struct btrfs_device_item);
printk("found key %Lu %Lu\n", key.objectid, key.offset);
ret = btrfs_open_disk(root, key.objectid, key.offset,
(char *)(dev_item + 1),
btrfs_device_pathlen(dev_item));
BUG_ON(ret);
path->slots[0]++;
}
btrfs_free_path(path);
mutex_unlock(&root->fs_info->fs_mutex);
return 0;
}
struct btrfs_root *open_ctree(struct super_block *sb)
{
struct btrfs_root *extent_root = kmalloc(sizeof(struct btrfs_root),
@@ -463,17 +568,26 @@ struct btrfs_root *open_ctree(struct super_block *sb)
if (!btrfs_super_root(disk_super))
return NULL;
i_size_write(fs_info->btree_inode,
btrfs_super_total_blocks(disk_super) <<
fs_info->btree_inode->i_blkbits);
radix_tree_delete(&fs_info->dev_radix, (u32)-2);
dev_lookup->block_start = btrfs_super_device_block_start(disk_super);
dev_lookup->num_blocks = btrfs_super_device_num_blocks(disk_super);
ret = radix_tree_insert(&fs_info->dev_radix,
dev_lookup->block_start +
dev_lookup->num_blocks, dev_lookup);
dev_lookup->num_blocks - 1, dev_lookup);
BUG_ON(ret);
fs_info->disk_super = disk_super;
dev_root->node = read_tree_block(tree_root,
btrfs_super_device_root(disk_super));
ret = read_device_info(dev_root);
BUG_ON(ret);
tree_root->node = read_tree_block(tree_root,
btrfs_super_root(disk_super));
BUG_ON(!tree_root->node);
@@ -562,7 +676,7 @@ static int free_dev_radix(struct btrfs_fs_info *fs_info)
close_bdev_excl(lookup[i]->bdev);
radix_tree_delete(&fs_info->dev_radix,
lookup[i]->block_start +
lookup[i]->num_blocks);
lookup[i]->num_blocks - 1);
kfree(lookup[i]);
}
}