[deliverable/linux.git] / fs / btrfs / file-item.c

#include <linux/module.h>
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"

#define MAX_CSUM_ITEMS(r) ((((BTRFS_LEAF_DATA_SIZE(r) - \
				 sizeof(struct btrfs_item)) / \
				sizeof(struct btrfs_csum_item)) - 1))
int btrfs_insert_file_extent(struct btrfs_trans_handle *trans,
			       struct btrfs_root *root,
			       u64 objectid, u64 pos,
			       u64 offset, u64 num_blocks)
{
	int ret = 0;
	struct btrfs_file_extent_item *item;
	struct btrfs_key file_key;
	struct btrfs_path *path;

	path = btrfs_alloc_path();
	BUG_ON(!path);
	btrfs_init_path(path);
	/*
	ret = btrfs_alloc_extent(trans, root, num_blocks, hint_block,
				 (u64)-1, &ins);
				 */
	BUG_ON(ret);
	file_key.objectid = objectid;
	file_key.offset = pos;
	file_key.flags = 0;
	btrfs_set_key_type(&file_key, BTRFS_EXTENT_DATA_KEY);

	ret = btrfs_insert_empty_item(trans, root, path, &file_key,
				      sizeof(*item));
	BUG_ON(ret);
	item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
			      struct btrfs_file_extent_item);
	btrfs_set_file_extent_disk_blocknr(item, offset);
	btrfs_set_file_extent_disk_num_blocks(item, num_blocks);
	btrfs_set_file_extent_offset(item, 0);
	btrfs_set_file_extent_num_blocks(item, num_blocks);
	btrfs_set_file_extent_generation(item, trans->transid);
	btrfs_mark_buffer_dirty(path->nodes[0]);
	btrfs_release_path(root, path);
	btrfs_free_path(path);
	return 0;
}

struct btrfs_csum_item *btrfs_lookup_csum(struct btrfs_trans_handle *trans,
					  struct btrfs_root *root,
					  struct btrfs_path *path,
					  u64 objectid, u64 offset,
					  int cow)
{
	int ret;
	struct btrfs_key file_key;
	struct btrfs_key found_key;
	struct btrfs_csum_item *item;
	struct btrfs_leaf *leaf;
	u64 csum_offset = 0;

	file_key.objectid = objectid;
	file_key.offset = offset;
	file_key.flags = 0;
	btrfs_set_key_type(&file_key, BTRFS_CSUM_ITEM_KEY);
printk("__lookup for %Lu\n", offset);
	ret = btrfs_search_slot(trans, root, &file_key, path, 0, cow);
	if (ret < 0)
		goto fail;
	leaf = btrfs_buffer_leaf(path->nodes[0]);
	if (ret > 0) {
		ret = 1;
		if (path->slots[0] == 0) {
printk("fail1\n");
			goto fail;
		}
		path->slots[0]--;
		btrfs_disk_key_to_cpu(&found_key,
				      &leaf->items[path->slots[0]].key);
		if (btrfs_key_type(&found_key) != BTRFS_CSUM_ITEM_KEY ||
		    found_key.objectid != objectid) {
printk("fail2 type %u %Lu %Lu\n", btrfs_key_type(&found_key), found_key.objectid, objectid);
			goto fail;
		}
		csum_offset = (offset - found_key.offset) >>
				root->fs_info->sb->s_blocksize_bits;
		if (csum_offset >=
		    btrfs_item_size(leaf->items + path->slots[0]) /
		    sizeof(struct btrfs_csum_item)) {
printk("fail3, csum offset %lu size %u\n", csum_offset, btrfs_item_size(leaf->items + path->slots[0]) / sizeof(struct btrfs_csum_item));
			goto fail;
		}
	}
	item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_csum_item);
	item += csum_offset;
	return item;
fail:
	if (ret > 0)
		ret = -ENOENT;
	return ERR_PTR(ret);
}


int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans,
			     struct btrfs_root *root,
			     struct btrfs_path *path, u64 objectid,
			     u64 offset, int mod)
{
	int ret;
	struct btrfs_key file_key;
	int ins_len = mod < 0 ? -1 : 0;
	int cow = mod != 0;
	struct btrfs_csum_item *csum_item;

	csum_item = btrfs_lookup_csum(trans, root, path, objectid, offset, 0);
	if (IS_ERR(csum_item))
		return PTR_ERR(csum_item);
	file_key.objectid = objectid;
	file_key.offset = btrfs_csum_extent_offset(csum_item);
	file_key.flags = 0;
	btrfs_set_key_type(&file_key, BTRFS_EXTENT_DATA_KEY);
	btrfs_release_path(root, path);
printk("lookup file extent searches for %Lu\n", file_key.offset);
	ret = btrfs_search_slot(trans, root, &file_key, path, ins_len, cow);
printk("ret is %d\n", ret);
	return ret;
}

int btrfs_csum_file_block(struct btrfs_trans_handle *trans,
			  struct btrfs_root *root,
			  u64 objectid, u64 offset,
			  u64 extent_offset,
			  char *data, size_t len)
{
	int ret;
	struct btrfs_key file_key;
	struct btrfs_key found_key;
	struct btrfs_path *path;
	struct btrfs_csum_item *item;
	struct btrfs_leaf *leaf;
	u64 csum_offset;

	path = btrfs_alloc_path();
	BUG_ON(!path);
	btrfs_init_path(path);

	item = btrfs_lookup_csum(trans, root, path, objectid, offset, 0);
	if (!IS_ERR(item))
		goto found;
	btrfs_release_path(root, path);
	file_key.objectid = objectid;
	file_key.offset = offset;
	file_key.flags = 0;
	btrfs_set_key_type(&file_key, BTRFS_CSUM_ITEM_KEY);
printk("searching for csum %Lu %Lu\n", objectid, offset);
	ret = btrfs_search_slot(trans, root, &file_key, path,
				sizeof(struct btrfs_csum_item), 1);
printk("ret %d\n", ret);
	if (ret < 0)
		goto fail;
	if (ret == 0) {
		BUG();
	}
	if (path->slots[0] == 0) {
		btrfs_release_path(root, path);
		goto insert;
	}
	path->slots[0]--;
	leaf = btrfs_buffer_leaf(path->nodes[0]);
	btrfs_disk_key_to_cpu(&found_key, &leaf->items[path->slots[0]].key);
printk("found key %Lu %Lu %u\n", found_key.objectid, found_key.offset, found_key.flags);
	csum_offset = (offset - found_key.offset) >>
			root->fs_info->sb->s_blocksize_bits;
printk("csum_offset %Lu\n", csum_offset);
	if (btrfs_key_type(&found_key) != BTRFS_CSUM_ITEM_KEY ||
	    found_key.objectid != objectid ||
	    csum_offset >= MAX_CSUM_ITEMS(root)) {
		btrfs_release_path(root, path);
printk("insert1\n");
		goto insert;
	}
	if (csum_offset >= btrfs_item_size(leaf->items + path->slots[0]) /
	    sizeof(struct btrfs_csum_item)) {
		ret = btrfs_extend_item(trans, root, path,
					sizeof(struct btrfs_csum_item));
		BUG_ON(ret);
printk("item extended\n");
		goto csum;
	}

insert:
	csum_offset = 0;
printk("inserting item %Lu %Lu %u\n", file_key.objectid, file_key.offset, file_key.flags);
	ret = btrfs_insert_empty_item(trans, root, path, &file_key,
				      sizeof(struct btrfs_csum_item));
	if (ret != 0 && ret != -EEXIST)
		goto fail;
csum:
	item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
			      struct btrfs_csum_item);
	ret = 0;
	item += csum_offset;
found:
	ret = btrfs_csum_data(root, data, len, item->csum);
	btrfs_set_csum_extent_offset(item, extent_offset);
	btrfs_mark_buffer_dirty(path->nodes[0]);
fail:
	btrfs_release_path(root, path);
	btrfs_free_path(path);
printk("return ret %d\n", ret);
	return ret;
}

int btrfs_csum_verify_file_block(struct btrfs_root *root,
				 u64 objectid, u64 offset,
				 char *data, size_t len)
{
	int ret;
	struct btrfs_key file_key;
	struct btrfs_path *path;
	struct btrfs_csum_item *item;
	char result[BTRFS_CSUM_SIZE];

	path = btrfs_alloc_path();
	BUG_ON(!path);
	btrfs_init_path(path);
	file_key.objectid = objectid;
	file_key.offset = offset;
	file_key.flags = 0;
	btrfs_set_key_type(&file_key, BTRFS_CSUM_ITEM_KEY);
	mutex_lock(&root->fs_info->fs_mutex);

	item = btrfs_lookup_csum(NULL, root, path, objectid, offset, 0);
	if (IS_ERR(item)) {
		ret = PTR_ERR(item);
		goto fail;
	}

	ret = btrfs_csum_data(root, data, len, result);
	WARN_ON(ret);
	if (memcmp(result, item->csum, BTRFS_CSUM_SIZE))
		ret = 1;
fail:
	btrfs_release_path(root, path);
	btrfs_free_path(path);
	mutex_unlock(&root->fs_info->fs_mutex);
	return ret;
}
Commit	Line	Data
	1	#include <linux/module.h>
	2	#include "ctree.h"
	3	#include "disk-io.h"
	4	#include "transaction.h"
	5
	6	#define MAX_CSUM_ITEMS(r) ((((BTRFS_LEAF_DATA_SIZE(r) - \
	7	sizeof(struct btrfs_item)) / \
	8	sizeof(struct btrfs_csum_item)) - 1))
	9	int btrfs_insert_file_extent(struct btrfs_trans_handle *trans,
	10	struct btrfs_root *root,
	11	u64 objectid, u64 pos,
	12	u64 offset, u64 num_blocks)
	13	{
	14	int ret = 0;
	15	struct btrfs_file_extent_item *item;
	16	struct btrfs_key file_key;
	17	struct btrfs_path *path;
	18
	19	path = btrfs_alloc_path();
	20	BUG_ON(!path);
	21	btrfs_init_path(path);
	22	/*
	23	ret = btrfs_alloc_extent(trans, root, num_blocks, hint_block,
	24	(u64)-1, &ins);
	25	*/
	26	BUG_ON(ret);
	27	file_key.objectid = objectid;
	28	file_key.offset = pos;
	29	file_key.flags = 0;
	30	btrfs_set_key_type(&file_key, BTRFS_EXTENT_DATA_KEY);
	31
	32	ret = btrfs_insert_empty_item(trans, root, path, &file_key,
	33	sizeof(*item));
	34	BUG_ON(ret);
	35	item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
	36	struct btrfs_file_extent_item);
	37	btrfs_set_file_extent_disk_blocknr(item, offset);
	38	btrfs_set_file_extent_disk_num_blocks(item, num_blocks);
	39	btrfs_set_file_extent_offset(item, 0);
	40	btrfs_set_file_extent_num_blocks(item, num_blocks);
	41	btrfs_set_file_extent_generation(item, trans->transid);
	42	btrfs_mark_buffer_dirty(path->nodes[0]);
	43	btrfs_release_path(root, path);
	44	btrfs_free_path(path);
	45	return 0;
	46	}
	47
	48	struct btrfs_csum_item btrfs_lookup_csum(struct btrfs_trans_handle trans,
	49	struct btrfs_root *root,
	50	struct btrfs_path *path,
	51	u64 objectid, u64 offset,
	52	int cow)
	53	{
	54	int ret;
	55	struct btrfs_key file_key;
	56	struct btrfs_key found_key;
	57	struct btrfs_csum_item *item;
	58	struct btrfs_leaf *leaf;
	59	u64 csum_offset = 0;
	60
	61	file_key.objectid = objectid;
	62	file_key.offset = offset;
	63	file_key.flags = 0;
	64	btrfs_set_key_type(&file_key, BTRFS_CSUM_ITEM_KEY);
	65	printk("__lookup for %Lu\n", offset);
	66	ret = btrfs_search_slot(trans, root, &file_key, path, 0, cow);
	67	if (ret < 0)
	68	goto fail;
	69	leaf = btrfs_buffer_leaf(path->nodes[0]);
	70	if (ret > 0) {
	71	ret = 1;
	72	if (path->slots[0] == 0) {
	73	printk("fail1\n");
	74	goto fail;
	75	}
	76	path->slots[0]--;
	77	btrfs_disk_key_to_cpu(&found_key,
	78	&leaf->items[path->slots[0]].key);
	79	if (btrfs_key_type(&found_key) != BTRFS_CSUM_ITEM_KEY \|\|
	80	found_key.objectid != objectid) {
	81	printk("fail2 type %u %Lu %Lu\n", btrfs_key_type(&found_key), found_key.objectid, objectid);
	82	goto fail;
	83	}
	84	csum_offset = (offset - found_key.offset) >>
	85	root->fs_info->sb->s_blocksize_bits;
	86	if (csum_offset >=
	87	btrfs_item_size(leaf->items + path->slots[0]) /
	88	sizeof(struct btrfs_csum_item)) {
	89	printk("fail3, csum offset %lu size %u\n", csum_offset, btrfs_item_size(leaf->items + path->slots[0]) / sizeof(struct btrfs_csum_item));
	90	goto fail;
	91	}
	92	}
	93	item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_csum_item);
	94	item += csum_offset;
	95	return item;
	96	fail:
	97	if (ret > 0)
	98	ret = -ENOENT;
	99	return ERR_PTR(ret);
	100	}
	101
	102
	103	int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans,
	104	struct btrfs_root *root,
	105	struct btrfs_path *path, u64 objectid,
	106	u64 offset, int mod)
	107	{
	108	int ret;
	109	struct btrfs_key file_key;
	110	int ins_len = mod < 0 ? -1 : 0;
	111	int cow = mod != 0;
	112	struct btrfs_csum_item *csum_item;
	113
	114	csum_item = btrfs_lookup_csum(trans, root, path, objectid, offset, 0);
	115	if (IS_ERR(csum_item))
	116	return PTR_ERR(csum_item);
	117	file_key.objectid = objectid;
	118	file_key.offset = btrfs_csum_extent_offset(csum_item);
	119	file_key.flags = 0;
	120	btrfs_set_key_type(&file_key, BTRFS_EXTENT_DATA_KEY);
	121	btrfs_release_path(root, path);
	122	printk("lookup file extent searches for %Lu\n", file_key.offset);
	123	ret = btrfs_search_slot(trans, root, &file_key, path, ins_len, cow);
	124	printk("ret is %d\n", ret);
	125	return ret;
	126	}
	127
	128	int btrfs_csum_file_block(struct btrfs_trans_handle *trans,
	129	struct btrfs_root *root,
	130	u64 objectid, u64 offset,
	131	u64 extent_offset,
	132	char *data, size_t len)
	133	{
	134	int ret;
	135	struct btrfs_key file_key;
	136	struct btrfs_key found_key;
	137	struct btrfs_path *path;
	138	struct btrfs_csum_item *item;
	139	struct btrfs_leaf *leaf;
	140	u64 csum_offset;
	141
	142	path = btrfs_alloc_path();
	143	BUG_ON(!path);
	144	btrfs_init_path(path);
	145
	146	item = btrfs_lookup_csum(trans, root, path, objectid, offset, 0);
	147	if (!IS_ERR(item))
	148	goto found;
	149	btrfs_release_path(root, path);
	150	file_key.objectid = objectid;
	151	file_key.offset = offset;
	152	file_key.flags = 0;
	153	btrfs_set_key_type(&file_key, BTRFS_CSUM_ITEM_KEY);
	154	printk("searching for csum %Lu %Lu\n", objectid, offset);
	155	ret = btrfs_search_slot(trans, root, &file_key, path,
	156	sizeof(struct btrfs_csum_item), 1);
	157	printk("ret %d\n", ret);
	158	if (ret < 0)
	159	goto fail;
	160	if (ret == 0) {
	161	BUG();
	162	}
	163	if (path->slots[0] == 0) {
	164	btrfs_release_path(root, path);
	165	goto insert;
	166	}
	167	path->slots[0]--;
	168	leaf = btrfs_buffer_leaf(path->nodes[0]);
	169	btrfs_disk_key_to_cpu(&found_key, &leaf->items[path->slots[0]].key);
	170	printk("found key %Lu %Lu %u\n", found_key.objectid, found_key.offset, found_key.flags);
	171	csum_offset = (offset - found_key.offset) >>
	172	root->fs_info->sb->s_blocksize_bits;
	173	printk("csum_offset %Lu\n", csum_offset);
	174	if (btrfs_key_type(&found_key) != BTRFS_CSUM_ITEM_KEY \|\|
	175	found_key.objectid != objectid \|\|
	176	csum_offset >= MAX_CSUM_ITEMS(root)) {
	177	btrfs_release_path(root, path);
	178	printk("insert1\n");
	179	goto insert;
	180	}
	181	if (csum_offset >= btrfs_item_size(leaf->items + path->slots[0]) /
	182	sizeof(struct btrfs_csum_item)) {
	183	ret = btrfs_extend_item(trans, root, path,
	184	sizeof(struct btrfs_csum_item));
	185	BUG_ON(ret);
	186	printk("item extended\n");
	187	goto csum;
	188	}
	189
	190	insert:
	191	csum_offset = 0;
	192	printk("inserting item %Lu %Lu %u\n", file_key.objectid, file_key.offset, file_key.flags);
	193	ret = btrfs_insert_empty_item(trans, root, path, &file_key,
	194	sizeof(struct btrfs_csum_item));
	195	if (ret != 0 && ret != -EEXIST)
	196	goto fail;
	197	csum:
	198	item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
	199	struct btrfs_csum_item);
	200	ret = 0;
	201	item += csum_offset;
	202	found:
	203	ret = btrfs_csum_data(root, data, len, item->csum);
	204	btrfs_set_csum_extent_offset(item, extent_offset);
	205	btrfs_mark_buffer_dirty(path->nodes[0]);
	206	fail:
	207	btrfs_release_path(root, path);
	208	btrfs_free_path(path);
	209	printk("return ret %d\n", ret);
	210	return ret;
	211	}
	212
	213	int btrfs_csum_verify_file_block(struct btrfs_root *root,
	214	u64 objectid, u64 offset,
	215	char *data, size_t len)
	216	{
	217	int ret;
	218	struct btrfs_key file_key;
	219	struct btrfs_path *path;
	220	struct btrfs_csum_item *item;
	221	char result[BTRFS_CSUM_SIZE];
	222
	223	path = btrfs_alloc_path();
	224	BUG_ON(!path);
	225	btrfs_init_path(path);
	226	file_key.objectid = objectid;
	227	file_key.offset = offset;
	228	file_key.flags = 0;
	229	btrfs_set_key_type(&file_key, BTRFS_CSUM_ITEM_KEY);
	230	mutex_lock(&root->fs_info->fs_mutex);
	231
	232	item = btrfs_lookup_csum(NULL, root, path, objectid, offset, 0);
	233	if (IS_ERR(item)) {
	234	ret = PTR_ERR(item);
	235	goto fail;
	236	}
	237
	238	ret = btrfs_csum_data(root, data, len, result);
	239	WARN_ON(ret);
	240	if (memcmp(result, item->csum, BTRFS_CSUM_SIZE))
	241	ret = 1;
	242	fail:
	243	btrfs_release_path(root, path);
	244	btrfs_free_path(path);
	245	mutex_unlock(&root->fs_info->fs_mutex);
	246	return ret;
	247	}
	248