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Btrfs: directory inode index is back
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Signed-off-by: Chris Mason <chris.mason@oracle.com>
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Chris Mason authored and David Woodhouse committed Apr 19, 2007
1 parent 236454d commit 7e38180
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Showing 4 changed files with 206 additions and 362 deletions.
4 changes: 2 additions & 2 deletions fs/btrfs/TODO
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Original file line number Diff line number Diff line change
@@ -1,12 +1,12 @@
* cleanup, add more error checking, get rid of BUG_ONs
* Fix ENOSPC handling
* Add block mapping tree (simple dm layer)
* Make allocator smarter
* add a block group to struct inode
* Make sure nobh stuff is working properly for cows
* Do actual block accounting
* Check compat and incompat flags on the inode
* Get rid of struct ctree_path, limiting tree levels held at one time
* Add generation number to key pointer in nodes
* Add parent pointer back to extent map.
* Release
* Do real tree locking
* Add extent mirroring (backup copies of blocks)
Expand Down
58 changes: 17 additions & 41 deletions fs/btrfs/ctree.h
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Original file line number Diff line number Diff line change
Expand Up @@ -185,11 +185,6 @@ struct btrfs_inode_item {
struct btrfs_inode_timespec otime;
} __attribute__ ((__packed__));

/* inline data is just a blob of bytes */
struct btrfs_inline_data_item {
u8 data;
} __attribute__ ((__packed__));

struct btrfs_dir_item {
struct btrfs_disk_key location;
__le16 flags;
Expand Down Expand Up @@ -293,9 +288,6 @@ struct btrfs_root {
#define BTRFS_KEY_TYPE_MASK (((u32)BTRFS_KEY_TYPE_MAX - 1) << \
BTRFS_KEY_TYPE_SHIFT)

#define BTRFS_KEY_OVERFLOW_MAX 128
#define BTRFS_KEY_OVERFLOW_MASK ((u32)BTRFS_KEY_OVERFLOW_MAX - 1)

/*
* inode items have the data typically returned from stat and store other
* info about object characteristics. There is one for every file and dir in
Expand Down Expand Up @@ -621,31 +613,6 @@ static inline void btrfs_set_key_type(struct btrfs_key *key, u32 val)
key->flags = (key->flags & ~(BTRFS_KEY_TYPE_MASK)) | val;
}

static inline u32 btrfs_key_overflow(struct btrfs_key *key)
{
return key->flags & BTRFS_KEY_OVERFLOW_MASK;
}

static inline void btrfs_set_key_overflow(struct btrfs_key *key, u32 over)
{
BUG_ON(over >= BTRFS_KEY_OVERFLOW_MAX);
key->flags = (key->flags & ~BTRFS_KEY_OVERFLOW_MASK) | over;
}

static inline u32 btrfs_disk_key_overflow(struct btrfs_disk_key *key)
{
return le32_to_cpu(key->flags) & BTRFS_KEY_OVERFLOW_MASK;
}

static inline void btrfs_set_disk_key_overflow(struct btrfs_disk_key *key,
u32 over)
{
u32 flags = btrfs_disk_key_flags(key);
BUG_ON(over >= BTRFS_KEY_OVERFLOW_MAX);
flags = (flags & ~BTRFS_KEY_OVERFLOW_MASK) | over;
btrfs_set_disk_key_flags(key, flags);
}

static inline u64 btrfs_header_blocknr(struct btrfs_header *h)
{
return le64_to_cpu(h->blocknr);
Expand Down Expand Up @@ -1079,15 +1046,24 @@ int btrfs_find_last_root(struct btrfs_root *root, u64 objectid, struct
int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
*root, const char *name, int name_len, u64 dir,
struct btrfs_key *location, u8 type);
int btrfs_lookup_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
*root, struct btrfs_path *path, u64 dir,
const char *name, int name_len, int mod);
int btrfs_lookup_dir_index_item(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path, u64 dir,
u64 objectid, int mod);
int btrfs_match_dir_item_name(struct btrfs_root *root, struct btrfs_path *path,
struct btrfs_dir_item *btrfs_lookup_dir_item(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path, u64 dir,
const char *name, int name_len,
int mod);
struct btrfs_dir_item *
btrfs_lookup_dir_index_item(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path, u64 dir,
u64 objectid, const char *name, int name_len,
int mod);
struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_root *root,
struct btrfs_path *path,
const char *name, int name_len);
int btrfs_delete_one_dir_name(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path,
struct btrfs_dir_item *di);
/* inode-map.c */
int btrfs_find_free_objectid(struct btrfs_trans_handle *trans,
struct btrfs_root *fs_root,
Expand Down
204 changes: 144 additions & 60 deletions fs/btrfs/dir-item.c
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Original file line number Diff line number Diff line change
Expand Up @@ -4,24 +4,31 @@
#include "hash.h"
#include "transaction.h"

int insert_with_overflow(struct btrfs_trans_handle *trans, struct btrfs_root
*root, struct btrfs_path *path, struct btrfs_key
*cpu_key, u32 data_size)
struct btrfs_dir_item *insert_with_overflow(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path,
struct btrfs_key *cpu_key,
u32 data_size)
{
int overflow;
int ret;
char *ptr;
struct btrfs_item *item;
struct btrfs_leaf *leaf;

ret = btrfs_insert_empty_item(trans, root, path, cpu_key, data_size);
overflow = btrfs_key_overflow(cpu_key);

while(ret == -EEXIST && overflow < BTRFS_KEY_OVERFLOW_MAX) {
overflow++;
btrfs_set_key_overflow(cpu_key, overflow);
btrfs_release_path(root, path);
ret = btrfs_insert_empty_item(trans, root, path, cpu_key,
data_size);
if (ret == -EEXIST) {
ret = btrfs_extend_item(trans, root, path, data_size);
WARN_ON(ret > 0);
if (ret)
return ERR_PTR(ret);
}
return ret;
WARN_ON(ret > 0);
leaf = btrfs_buffer_leaf(path->nodes[0]);
item = leaf->items + path->slots[0];
ptr = btrfs_item_ptr(leaf, path->slots[0], char);
BUG_ON(data_size > btrfs_item_size(item));
ptr += btrfs_item_size(item) - data_size;
return (struct btrfs_dir_item *)ptr;
}

int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
Expand All @@ -43,13 +50,12 @@ int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
path = btrfs_alloc_path();
btrfs_init_path(path);
data_size = sizeof(*dir_item) + name_len;
ret = insert_with_overflow(trans, root, path, &key, data_size);
if (ret)
dir_item = insert_with_overflow(trans, root, path, &key, data_size);
if (IS_ERR(dir_item)) {
ret = PTR_ERR(dir_item);
goto out;
}

dir_item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
path->slots[0],
struct btrfs_dir_item);
btrfs_cpu_key_to_disk(&dir_item->location, location);
btrfs_set_dir_type(dir_item, type);
btrfs_set_dir_flags(dir_item, 0);
Expand All @@ -58,73 +64,151 @@ int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root

btrfs_memcpy(root, path->nodes[0]->b_data, name_ptr, name, name_len);
btrfs_mark_buffer_dirty(path->nodes[0]);
out:

/* FIXME, use some real flag for selecting the extra index */
if (root == root->fs_info->tree_root) {
ret = 0;
goto out;
}

btrfs_release_path(root, path);

btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
key.offset = location->objectid;
dir_item = insert_with_overflow(trans, root, path, &key, data_size);
if (IS_ERR(dir_item)) {
ret = PTR_ERR(dir_item);
goto out;
}
btrfs_cpu_key_to_disk(&dir_item->location, location);
btrfs_set_dir_type(dir_item, type);
btrfs_set_dir_flags(dir_item, 0);
btrfs_set_dir_name_len(dir_item, name_len);
name_ptr = (char *)(dir_item + 1);
btrfs_memcpy(root, path->nodes[0]->b_data, name_ptr, name, name_len);
btrfs_mark_buffer_dirty(path->nodes[0]);
out:
btrfs_free_path(path);
return ret;
}

int btrfs_lookup_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
*root, struct btrfs_path *path, u64 dir,
const char *name, int name_len, int mod)
struct btrfs_dir_item *btrfs_lookup_dir_item(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path, u64 dir,
const char *name, int name_len,
int mod)
{
int ret;
struct btrfs_key key;
int ins_len = mod < 0 ? -1 : 0;
int cow = mod != 0;
struct btrfs_disk_key *found_key;
struct btrfs_leaf *leaf;
u32 overflow;

key.objectid = dir;
key.flags = 0;
btrfs_set_key_type(&key, BTRFS_DIR_ITEM_KEY);
// btrfs_set_key_overflow(&key, BTRFS_KEY_OVERFLOW_MAX - 1);
ret = btrfs_name_hash(name, name_len, &key.offset);
BUG_ON(ret);
while(1) {
ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
if (ret < 0)
return ret;
if (ret > 0) {
if (path->slots[0] == 0)
return 1;
path->slots[0]--;
}
leaf = btrfs_buffer_leaf(path->nodes[0]);
found_key = &leaf->items[path->slots[0]].key;

if (btrfs_disk_key_objectid(found_key) != dir ||
btrfs_disk_key_type(found_key) != BTRFS_DIR_ITEM_KEY ||
btrfs_disk_key_offset(found_key) != key.offset)
return 1;

if (btrfs_match_dir_item_name(root, path, name, name_len))
return 0;

overflow = btrfs_disk_key_overflow(found_key);
if (overflow == 0)
return 1;
btrfs_set_key_overflow(&key, overflow - 1);
btrfs_release_path(root, path);
ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
if (ret < 0)
return ERR_PTR(ret);
if (ret > 0) {
if (path->slots[0] == 0)
return NULL;
path->slots[0]--;
}
return 1;
leaf = btrfs_buffer_leaf(path->nodes[0]);
found_key = &leaf->items[path->slots[0]].key;

if (btrfs_disk_key_objectid(found_key) != dir ||
btrfs_disk_key_type(found_key) != BTRFS_DIR_ITEM_KEY ||
btrfs_disk_key_offset(found_key) != key.offset)
return NULL;

return btrfs_match_dir_item_name(root, path, name, name_len);
}

int btrfs_match_dir_item_name(struct btrfs_root *root,
struct btrfs_dir_item *
btrfs_lookup_dir_index_item(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path, u64 dir,
u64 objectid, const char *name, int name_len,
int mod)
{
int ret;
struct btrfs_key key;
int ins_len = mod < 0 ? -1 : 0;
int cow = mod != 0;

key.objectid = dir;
key.flags = 0;
btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
key.offset = objectid;

ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
if (ret < 0)
return ERR_PTR(ret);
if (ret > 0)
return ERR_PTR(-ENOENT);
return btrfs_match_dir_item_name(root, path, name, name_len);
}

struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_root *root,
struct btrfs_path *path,
const char *name, int name_len)
{
struct btrfs_dir_item *dir_item;
char *name_ptr;
u32 total_len;
u32 cur = 0;
u32 this_len;
struct btrfs_leaf *leaf;

dir_item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
path->slots[0],
struct btrfs_dir_item);
if (btrfs_dir_name_len(dir_item) != name_len)
return 0;
name_ptr = (char *)(dir_item + 1);
if (memcmp(name_ptr, name, name_len))
return 0;
return 1;
leaf = btrfs_buffer_leaf(path->nodes[0]);
dir_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dir_item);
total_len = btrfs_item_size(leaf->items + path->slots[0]);
while(cur < total_len) {
this_len = sizeof(*dir_item) + btrfs_dir_name_len(dir_item);
name_ptr = (char *)(dir_item + 1);

if (btrfs_dir_name_len(dir_item) == name_len &&
memcmp(name_ptr, name, name_len) == 0)
return dir_item;

cur += this_len;
dir_item = (struct btrfs_dir_item *)((char *)dir_item +
this_len);
}
return NULL;
}

int btrfs_delete_one_dir_name(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path,
struct btrfs_dir_item *di)
{

struct btrfs_leaf *leaf;
u32 sub_item_len;
u32 item_len;
int ret;

leaf = btrfs_buffer_leaf(path->nodes[0]);
sub_item_len = sizeof(*di) + btrfs_dir_name_len(di);
item_len = btrfs_item_size(leaf->items + path->slots[0]);
if (sub_item_len == btrfs_item_size(leaf->items + path->slots[0])) {
ret = btrfs_del_item(trans, root, path);
BUG_ON(ret);
} else {
char *ptr = (char *)di;
char *start = btrfs_item_ptr(leaf, path->slots[0], char);
btrfs_memmove(root, leaf, ptr, ptr + sub_item_len,
item_len - (ptr + sub_item_len - start));
ret = btrfs_truncate_item(trans, root, path,
item_len - sub_item_len);
BUG_ON(ret);
}
return 0;
}

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