Btrfs: Add a write ahead tree log to optimize synchronous operations
File syncs and directory syncs are optimized by copying their
items into a special (copy-on-write) log tree. There is one log tree per
subvolume and the btrfs super block points to a tree of log tree roots.
After a crash, items are copied out of the log tree and back into the
subvolume. See tree-log.c for all the details.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 43d3f264..65df9d8 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -46,6 +46,8 @@
#include "volumes.h"
#include "ordered-data.h"
#include "xattr.h"
+#include "compat.h"
+#include "tree-log.h"
struct btrfs_iget_args {
u64 ino;
@@ -586,6 +588,7 @@
&ordered_extent->list);
btrfs_ordered_update_i_size(inode, ordered_extent);
+ btrfs_update_inode(trans, root, inode);
btrfs_remove_ordered_extent(inode, ordered_extent);
/* once for us */
@@ -593,7 +596,6 @@
/* once for the tree */
btrfs_put_ordered_extent(ordered_extent);
- btrfs_update_inode(trans, root, inode);
btrfs_end_transaction(trans, root);
return 0;
}
@@ -1007,7 +1009,8 @@
inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
inode->i_blocks = btrfs_inode_nblocks(leaf, inode_item);
- inode->i_generation = btrfs_inode_generation(leaf, inode_item);
+ BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item);
+ inode->i_generation = BTRFS_I(inode)->generation;
inode->i_rdev = 0;
rdev = btrfs_inode_rdev(leaf, inode_item);
@@ -1056,7 +1059,8 @@
make_bad_inode(inode);
}
-static void fill_inode_item(struct extent_buffer *leaf,
+static void fill_inode_item(struct btrfs_trans_handle *trans,
+ struct extent_buffer *leaf,
struct btrfs_inode_item *item,
struct inode *inode)
{
@@ -1082,7 +1086,8 @@
inode->i_ctime.tv_nsec);
btrfs_set_inode_nblocks(leaf, item, inode->i_blocks);
- btrfs_set_inode_generation(leaf, item, inode->i_generation);
+ btrfs_set_inode_generation(leaf, item, BTRFS_I(inode)->generation);
+ btrfs_set_inode_transid(leaf, item, trans->transid);
btrfs_set_inode_rdev(leaf, item, inode->i_rdev);
btrfs_set_inode_flags(leaf, item, BTRFS_I(inode)->flags);
btrfs_set_inode_block_group(leaf, item,
@@ -1112,7 +1117,7 @@
inode_item = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_inode_item);
- fill_inode_item(leaf, inode_item, inode);
+ fill_inode_item(trans, leaf, inode_item, inode);
btrfs_mark_buffer_dirty(leaf);
btrfs_set_inode_last_trans(trans, inode);
ret = 0;
@@ -1122,14 +1127,12 @@
}
-static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- struct inode *dir,
- struct dentry *dentry)
+int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct inode *dir, struct inode *inode,
+ const char *name, int name_len)
{
struct btrfs_path *path;
- const char *name = dentry->d_name.name;
- int name_len = dentry->d_name.len;
int ret = 0;
struct extent_buffer *leaf;
struct btrfs_dir_item *di;
@@ -1160,13 +1163,12 @@
btrfs_release_path(root, path);
ret = btrfs_del_inode_ref(trans, root, name, name_len,
- dentry->d_inode->i_ino,
- dentry->d_parent->d_inode->i_ino, &index);
+ inode->i_ino,
+ dir->i_ino, &index);
if (ret) {
printk("failed to delete reference to %.*s, "
"inode %lu parent %lu\n", name_len, name,
- dentry->d_inode->i_ino,
- dentry->d_parent->d_inode->i_ino);
+ inode->i_ino, dir->i_ino);
goto err;
}
@@ -1183,21 +1185,25 @@
ret = btrfs_delete_one_dir_name(trans, root, path, di);
btrfs_release_path(root, path);
- dentry->d_inode->i_ctime = dir->i_ctime;
+ ret = btrfs_del_inode_ref_in_log(trans, root, name, name_len,
+ inode, dir->i_ino);
+ BUG_ON(ret);
+
+ ret = btrfs_del_dir_entries_in_log(trans, root, name, name_len,
+ dir, index);
+ BUG_ON(ret);
err:
btrfs_free_path(path);
- if (!ret) {
- btrfs_i_size_write(dir, dir->i_size - name_len * 2);
- dir->i_mtime = dir->i_ctime = CURRENT_TIME;
- btrfs_update_inode(trans, root, dir);
-#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
- dentry->d_inode->i_nlink--;
-#else
- drop_nlink(dentry->d_inode);
-#endif
- ret = btrfs_update_inode(trans, root, dentry->d_inode);
- dir->i_sb->s_dirt = 1;
- }
+ if (ret)
+ goto out;
+
+ btrfs_i_size_write(dir, dir->i_size - name_len * 2);
+ inode->i_ctime = dir->i_mtime = dir->i_ctime = CURRENT_TIME;
+ btrfs_update_inode(trans, root, dir);
+ btrfs_drop_nlink(inode);
+ ret = btrfs_update_inode(trans, root, inode);
+ dir->i_sb->s_dirt = 1;
+out:
return ret;
}
@@ -1218,7 +1224,8 @@
trans = btrfs_start_transaction(root, 1);
btrfs_set_trans_block_group(trans, dir);
- ret = btrfs_unlink_trans(trans, root, dir, dentry);
+ ret = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
+ dentry->d_name.name, dentry->d_name.len);
if (inode->i_nlink == 0)
ret = btrfs_orphan_add(trans, inode);
@@ -1256,7 +1263,8 @@
goto fail_trans;
/* now the directory is empty */
- err = btrfs_unlink_trans(trans, root, dir, dentry);
+ err = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
+ dentry->d_name.name, dentry->d_name.len);
if (!err) {
btrfs_i_size_write(inode, 0);
}
@@ -1283,10 +1291,10 @@
* min_type is the minimum key type to truncate down to. If set to 0, this
* will kill all the items on this inode, including the INODE_ITEM_KEY.
*/
-static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- struct inode *inode,
- u32 min_type)
+noinline int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct inode *inode,
+ u64 new_size, u32 min_type)
{
int ret;
struct btrfs_path *path;
@@ -1307,7 +1315,9 @@
int extent_type = -1;
u64 mask = root->sectorsize - 1;
- btrfs_drop_extent_cache(inode, inode->i_size & (~mask), (u64)-1);
+ if (root->ref_cows)
+ btrfs_drop_extent_cache(inode,
+ new_size & (~mask), (u64)-1);
path = btrfs_alloc_path();
path->reada = -1;
BUG_ON(!path);
@@ -1324,7 +1334,13 @@
goto error;
}
if (ret > 0) {
- BUG_ON(path->slots[0] == 0);
+ /* there are no items in the tree for us to truncate, we're
+ * done
+ */
+ if (path->slots[0] == 0) {
+ ret = 0;
+ goto error;
+ }
path->slots[0]--;
}
@@ -1358,10 +1374,10 @@
}
if (found_type == BTRFS_CSUM_ITEM_KEY) {
ret = btrfs_csum_truncate(trans, root, path,
- inode->i_size);
+ new_size);
BUG_ON(ret);
}
- if (item_end < inode->i_size) {
+ if (item_end < new_size) {
if (found_type == BTRFS_DIR_ITEM_KEY) {
found_type = BTRFS_INODE_ITEM_KEY;
} else if (found_type == BTRFS_EXTENT_ITEM_KEY) {
@@ -1378,7 +1394,7 @@
btrfs_set_key_type(&key, found_type);
goto next;
}
- if (found_key.offset >= inode->i_size)
+ if (found_key.offset >= new_size)
del_item = 1;
else
del_item = 0;
@@ -1394,7 +1410,7 @@
if (!del_item) {
u64 orig_num_bytes =
btrfs_file_extent_num_bytes(leaf, fi);
- extent_num_bytes = inode->i_size -
+ extent_num_bytes = new_size -
found_key.offset + root->sectorsize - 1;
extent_num_bytes = extent_num_bytes &
~((u64)root->sectorsize - 1);
@@ -1402,7 +1418,7 @@
extent_num_bytes);
num_dec = (orig_num_bytes -
extent_num_bytes);
- if (extent_start != 0)
+ if (root->ref_cows && extent_start != 0)
dec_i_blocks(inode, num_dec);
btrfs_mark_buffer_dirty(leaf);
} else {
@@ -1413,22 +1429,29 @@
num_dec = btrfs_file_extent_num_bytes(leaf, fi);
if (extent_start != 0) {
found_extent = 1;
- dec_i_blocks(inode, num_dec);
+ if (root->ref_cows)
+ dec_i_blocks(inode, num_dec);
}
- root_gen = btrfs_header_generation(leaf);
+ if (root->ref_cows) {
+ root_gen =
+ btrfs_header_generation(leaf);
+ }
root_owner = btrfs_header_owner(leaf);
}
} else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
if (!del_item) {
- u32 newsize = inode->i_size - found_key.offset;
- dec_i_blocks(inode, item_end + 1 -
- found_key.offset - newsize);
- newsize =
- btrfs_file_extent_calc_inline_size(newsize);
+ u32 size = new_size - found_key.offset;
+
+ if (root->ref_cows) {
+ dec_i_blocks(inode, item_end + 1 -
+ found_key.offset - size);
+ }
+ size =
+ btrfs_file_extent_calc_inline_size(size);
ret = btrfs_truncate_item(trans, root, path,
- newsize, 1);
+ size, 1);
BUG_ON(ret);
- } else {
+ } else if (root->ref_cows) {
dec_i_blocks(inode, item_end + 1 -
found_key.offset);
}
@@ -1666,7 +1689,7 @@
trans = btrfs_start_transaction(root, 1);
btrfs_set_trans_block_group(trans, inode);
- ret = btrfs_truncate_in_trans(trans, root, inode, 0);
+ ret = btrfs_truncate_inode_items(trans, root, inode, inode->i_size, 0);
if (ret) {
btrfs_orphan_del(NULL, inode);
goto no_delete_lock;
@@ -1753,15 +1776,20 @@
return 0;
}
-static int btrfs_init_locked_inode(struct inode *inode, void *p)
+static noinline void init_btrfs_i(struct inode *inode)
{
- struct btrfs_iget_args *args = p;
- inode->i_ino = args->ino;
- BTRFS_I(inode)->root = args->root;
- BTRFS_I(inode)->delalloc_bytes = 0;
- inode->i_mapping->writeback_index = 0;
- BTRFS_I(inode)->disk_i_size = 0;
- BTRFS_I(inode)->index_cnt = (u64)-1;
+ struct btrfs_inode *bi = BTRFS_I(inode);
+
+ bi->i_acl = NULL;
+ bi->i_default_acl = NULL;
+
+ bi->generation = 0;
+ bi->last_trans = 0;
+ bi->logged_trans = 0;
+ bi->delalloc_bytes = 0;
+ bi->disk_i_size = 0;
+ bi->flags = 0;
+ bi->index_cnt = (u64)-1;
extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
extent_io_tree_init(&BTRFS_I(inode)->io_tree,
inode->i_mapping, GFP_NOFS);
@@ -1771,6 +1799,15 @@
btrfs_ordered_inode_tree_init(&BTRFS_I(inode)->ordered_tree);
mutex_init(&BTRFS_I(inode)->csum_mutex);
mutex_init(&BTRFS_I(inode)->extent_mutex);
+ mutex_init(&BTRFS_I(inode)->log_mutex);
+}
+
+static int btrfs_init_locked_inode(struct inode *inode, void *p)
+{
+ struct btrfs_iget_args *args = p;
+ inode->i_ino = args->ino;
+ init_btrfs_i(inode);
+ BTRFS_I(inode)->root = args->root;
return 0;
}
@@ -2263,21 +2300,10 @@
* btrfs_get_inode_index_count has an explanation for the magic
* number
*/
+ init_btrfs_i(inode);
BTRFS_I(inode)->index_cnt = 2;
-
- extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
- extent_io_tree_init(&BTRFS_I(inode)->io_tree,
- inode->i_mapping, GFP_NOFS);
- extent_io_tree_init(&BTRFS_I(inode)->io_failure_tree,
- inode->i_mapping, GFP_NOFS);
- btrfs_ordered_inode_tree_init(&BTRFS_I(inode)->ordered_tree);
- INIT_LIST_HEAD(&BTRFS_I(inode)->delalloc_inodes);
- mutex_init(&BTRFS_I(inode)->csum_mutex);
- mutex_init(&BTRFS_I(inode)->extent_mutex);
- BTRFS_I(inode)->delalloc_bytes = 0;
- inode->i_mapping->writeback_index = 0;
- BTRFS_I(inode)->disk_i_size = 0;
BTRFS_I(inode)->root = root;
+ BTRFS_I(inode)->generation = trans->transid;
if (mode & S_IFDIR)
owner = 0;
@@ -2290,7 +2316,6 @@
new_inode_group = group;
}
BTRFS_I(inode)->block_group = new_inode_group;
- BTRFS_I(inode)->flags = 0;
key[0].objectid = objectid;
btrfs_set_key_type(&key[0], BTRFS_INODE_ITEM_KEY);
@@ -2318,7 +2343,7 @@
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
struct btrfs_inode_item);
- fill_inode_item(path->nodes[0], inode_item, inode);
+ fill_inode_item(trans, path->nodes[0], inode_item, inode);
ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
struct btrfs_inode_ref);
@@ -2349,38 +2374,34 @@
return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
}
-static int btrfs_add_link(struct btrfs_trans_handle *trans,
- struct dentry *dentry, struct inode *inode,
- int add_backref, u64 index)
+int btrfs_add_link(struct btrfs_trans_handle *trans,
+ struct inode *parent_inode, struct inode *inode,
+ const char *name, int name_len, int add_backref, u64 index)
{
int ret;
struct btrfs_key key;
- struct btrfs_root *root = BTRFS_I(dentry->d_parent->d_inode)->root;
- struct inode *parent_inode = dentry->d_parent->d_inode;
+ struct btrfs_root *root = BTRFS_I(parent_inode)->root;
key.objectid = inode->i_ino;
btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
key.offset = 0;
- ret = btrfs_insert_dir_item(trans, root,
- dentry->d_name.name, dentry->d_name.len,
- dentry->d_parent->d_inode->i_ino,
+ ret = btrfs_insert_dir_item(trans, root, name, name_len,
+ parent_inode->i_ino,
&key, btrfs_inode_type(inode),
index);
if (ret == 0) {
if (add_backref) {
ret = btrfs_insert_inode_ref(trans, root,
- dentry->d_name.name,
- dentry->d_name.len,
- inode->i_ino,
- parent_inode->i_ino,
- index);
+ name, name_len,
+ inode->i_ino,
+ parent_inode->i_ino,
+ index);
}
btrfs_i_size_write(parent_inode, parent_inode->i_size +
- dentry->d_name.len * 2);
+ name_len * 2);
parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
- ret = btrfs_update_inode(trans, root,
- dentry->d_parent->d_inode);
+ ret = btrfs_update_inode(trans, root, parent_inode);
}
return ret;
}
@@ -2389,7 +2410,9 @@
struct dentry *dentry, struct inode *inode,
int backref, u64 index)
{
- int err = btrfs_add_link(trans, dentry, inode, backref, index);
+ int err = btrfs_add_link(trans, dentry->d_parent->d_inode,
+ inode, dentry->d_name.name,
+ dentry->d_name.len, backref, index);
if (!err) {
d_instantiate(dentry, inode);
return 0;
@@ -2513,19 +2536,7 @@
inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
inode->i_fop = &btrfs_file_operations;
inode->i_op = &btrfs_file_inode_operations;
- extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
- extent_io_tree_init(&BTRFS_I(inode)->io_tree,
- inode->i_mapping, GFP_NOFS);
- extent_io_tree_init(&BTRFS_I(inode)->io_failure_tree,
- inode->i_mapping, GFP_NOFS);
- INIT_LIST_HEAD(&BTRFS_I(inode)->delalloc_inodes);
- mutex_init(&BTRFS_I(inode)->csum_mutex);
- mutex_init(&BTRFS_I(inode)->extent_mutex);
- BTRFS_I(inode)->delalloc_bytes = 0;
- BTRFS_I(inode)->disk_i_size = 0;
- inode->i_mapping->writeback_index = 0;
BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
- btrfs_ordered_inode_tree_init(&BTRFS_I(inode)->ordered_tree);
}
dir->i_sb->s_dirt = 1;
btrfs_update_inode_block_group(trans, inode);
@@ -2556,11 +2567,7 @@
if (inode->i_nlink == 0)
return -ENOENT;
-#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
- inode->i_nlink++;
-#else
- inc_nlink(inode);
-#endif
+ btrfs_inc_nlink(inode);
err = btrfs_check_free_space(root, 1, 0);
if (err)
goto fail;
@@ -2650,7 +2657,9 @@
if (err)
goto out_fail;
- err = btrfs_add_link(trans, dentry, inode, 0, index);
+ err = btrfs_add_link(trans, dentry->d_parent->d_inode,
+ inode, dentry->d_name.name,
+ dentry->d_name.len, 0, index);
if (err)
goto out_fail;
@@ -3221,7 +3230,7 @@
if (ret)
goto out;
/* FIXME, add redo link to tree so we don't leak on crash */
- ret = btrfs_truncate_in_trans(trans, root, inode,
+ ret = btrfs_truncate_inode_items(trans, root, inode, inode->i_size,
BTRFS_EXTENT_DATA_KEY);
btrfs_update_inode(trans, root, inode);
@@ -3304,6 +3313,7 @@
if (!ei)
return NULL;
ei->last_trans = 0;
+ ei->logged_trans = 0;
btrfs_ordered_inode_tree_init(&ei->ordered_tree);
ei->i_acl = BTRFS_ACL_NOT_CACHED;
ei->i_default_acl = BTRFS_ACL_NOT_CACHED;
@@ -3463,31 +3473,39 @@
btrfs_set_trans_block_group(trans, new_dir);
- old_dentry->d_inode->i_nlink++;
+ btrfs_inc_nlink(old_dentry->d_inode);
old_dir->i_ctime = old_dir->i_mtime = ctime;
new_dir->i_ctime = new_dir->i_mtime = ctime;
old_inode->i_ctime = ctime;
- ret = btrfs_unlink_trans(trans, root, old_dir, old_dentry);
+ ret = btrfs_unlink_inode(trans, root, old_dir, old_dentry->d_inode,
+ old_dentry->d_name.name,
+ old_dentry->d_name.len);
if (ret)
goto out_fail;
if (new_inode) {
new_inode->i_ctime = CURRENT_TIME;
- ret = btrfs_unlink_trans(trans, root, new_dir, new_dentry);
+ ret = btrfs_unlink_inode(trans, root, new_dir,
+ new_dentry->d_inode,
+ new_dentry->d_name.name,
+ new_dentry->d_name.len);
if (ret)
goto out_fail;
if (new_inode->i_nlink == 0) {
- ret = btrfs_orphan_add(trans, new_inode);
+ ret = btrfs_orphan_add(trans, new_dentry->d_inode);
if (ret)
goto out_fail;
}
+
}
ret = btrfs_set_inode_index(new_dir, old_inode, &index);
if (ret)
goto out_fail;
- ret = btrfs_add_link(trans, new_dentry, old_inode, 1, index);
+ ret = btrfs_add_link(trans, new_dentry->d_parent->d_inode,
+ old_inode, new_dentry->d_name.name,
+ new_dentry->d_name.len, 1, index);
if (ret)
goto out_fail;
@@ -3577,19 +3595,7 @@
inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
inode->i_fop = &btrfs_file_operations;
inode->i_op = &btrfs_file_inode_operations;
- extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
- extent_io_tree_init(&BTRFS_I(inode)->io_tree,
- inode->i_mapping, GFP_NOFS);
- extent_io_tree_init(&BTRFS_I(inode)->io_failure_tree,
- inode->i_mapping, GFP_NOFS);
- INIT_LIST_HEAD(&BTRFS_I(inode)->delalloc_inodes);
- mutex_init(&BTRFS_I(inode)->csum_mutex);
- mutex_init(&BTRFS_I(inode)->extent_mutex);
- BTRFS_I(inode)->delalloc_bytes = 0;
- BTRFS_I(inode)->disk_i_size = 0;
- inode->i_mapping->writeback_index = 0;
BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
- btrfs_ordered_inode_tree_init(&BTRFS_I(inode)->ordered_tree);
}
dir->i_sb->s_dirt = 1;
btrfs_update_inode_block_group(trans, inode);
@@ -3691,6 +3697,7 @@
.compat_ioctl = btrfs_ioctl,
#endif
.release = btrfs_release_file,
+ .fsync = btrfs_sync_file,
};
static struct extent_io_ops btrfs_extent_io_ops = {