Commit 79154b1b authored by Chris Mason's avatar Chris Mason Committed by David Woodhouse

Btrfs: transaction rework

Signed-off-by: default avatarChris Mason <chris.mason@oracle.com>
parent e20d96d6
......@@ -3,7 +3,7 @@ ifneq ($(KERNELRELEASE),)
obj-m := btrfs.o
btrfs-y := super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \
hash.o file-item.o inode-item.o inode-map.o disk-io.o
hash.o file-item.o inode-item.o inode-map.o disk-io.o transaction.o
#btrfs-y := ctree.o disk-io.o radix-tree.o extent-tree.o print-tree.o \
# root-tree.o dir-item.o hash.o file-item.o inode-item.o \
......
......@@ -5,6 +5,7 @@
#include <linux/fs.h>
struct btrfs_trans_handle;
struct btrfs_transaction;
#define BTRFS_MAGIC "_BtRfS_M"
......@@ -224,10 +225,11 @@ struct btrfs_fs_info {
u64 last_inode_alloc;
u64 last_inode_alloc_dirid;
u64 generation;
struct btrfs_trans_handle *running_transaction;
struct btrfs_transaction *running_transaction;
struct btrfs_super_block *disk_super;
struct buffer_head *sb_buffer;
struct super_block *sb;
struct mutex trans_mutex;
};
/*
......
......@@ -50,89 +50,6 @@ int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
return 0;
}
int write_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
struct buffer_head *buf)
{
mark_buffer_dirty(buf);
return 0;
}
static int __commit_transaction(struct btrfs_trans_handle *trans, struct
btrfs_root *root)
{
filemap_write_and_wait(root->fs_info->sb->s_bdev->bd_inode->i_mapping);
return 0;
}
static int commit_tree_roots(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info)
{
int ret;
u64 old_extent_block;
struct btrfs_root *tree_root = fs_info->tree_root;
struct btrfs_root *extent_root = fs_info->extent_root;
struct btrfs_root *inode_root = fs_info->inode_root;
btrfs_set_root_blocknr(&inode_root->root_item,
inode_root->node->b_blocknr);
ret = btrfs_update_root(trans, tree_root,
&inode_root->root_key,
&inode_root->root_item);
BUG_ON(ret);
while(1) {
old_extent_block = btrfs_root_blocknr(&extent_root->root_item);
if (old_extent_block == extent_root->node->b_blocknr)
break;
btrfs_set_root_blocknr(&extent_root->root_item,
extent_root->node->b_blocknr);
ret = btrfs_update_root(trans, tree_root,
&extent_root->root_key,
&extent_root->root_item);
BUG_ON(ret);
}
return 0;
}
int btrfs_commit_transaction(struct btrfs_trans_handle *trans, struct
btrfs_root *root, struct btrfs_super_block *s)
{
int ret = 0;
struct buffer_head *snap = root->commit_root;
struct btrfs_key snap_key;
if (root->commit_root == root->node)
return 0;
memcpy(&snap_key, &root->root_key, sizeof(snap_key));
root->root_key.offset++;
btrfs_set_root_blocknr(&root->root_item, root->node->b_blocknr);
ret = btrfs_insert_root(trans, root->fs_info->tree_root,
&root->root_key, &root->root_item);
BUG_ON(ret);
ret = commit_tree_roots(trans, root->fs_info);
BUG_ON(ret);
ret = __commit_transaction(trans, root);
BUG_ON(ret);
write_ctree_super(trans, root, s);
btrfs_finish_extent_commit(trans, root->fs_info->extent_root);
btrfs_finish_extent_commit(trans, root->fs_info->tree_root);
root->commit_root = root->node;
get_bh(root->node);
ret = btrfs_drop_snapshot(trans, root, snap);
BUG_ON(ret);
ret = btrfs_del_root(trans, root->fs_info->tree_root, &snap_key);
BUG_ON(ret);
root->fs_info->generation = root->root_key.offset + 1;
return ret;
}
static int __setup_root(struct btrfs_super_block *super,
struct btrfs_root *root,
struct btrfs_fs_info *fs_info,
......@@ -197,6 +114,7 @@ struct btrfs_root *open_ctree(struct super_block *sb,
fs_info->disk_super = disk_super;
fs_info->sb_buffer = sb_buffer;
fs_info->sb = sb;
mutex_init(&fs_info->trans_mutex);
memset(&fs_info->current_insert, 0, sizeof(fs_info->current_insert));
memset(&fs_info->last_insert, 0, sizeof(fs_info->last_insert));
......@@ -225,7 +143,7 @@ struct btrfs_root *open_ctree(struct super_block *sb,
}
int write_ctree_super(struct btrfs_trans_handle *trans, struct btrfs_root
*root, struct btrfs_super_block *s)
*root)
{
return 0;
#if 0
......@@ -242,34 +160,19 @@ int write_ctree_super(struct btrfs_trans_handle *trans, struct btrfs_root
#endif
}
static int drop_cache(struct btrfs_root *root)
{
return 0;
#if 0
while(!list_empty(&root->fs_info->cache)) {
struct buffer_head *b = list_entry(root->fs_info->cache.next,
struct buffer_head,
cache);
list_del_init(&b->cache);
btrfs_block_release(root, b);
}
return 0;
#endif
}
int close_ctree(struct btrfs_root *root)
{
int ret;
struct btrfs_trans_handle *trans;
trans = root->fs_info->running_transaction;
btrfs_commit_transaction(trans, root, root->fs_info->disk_super);
ret = commit_tree_roots(trans, root->fs_info);
BUG_ON(ret);
ret = __commit_transaction(trans, root);
trans = btrfs_start_transaction(root, 1);
btrfs_commit_transaction(trans, root);
/* run commit again to drop the original snapshot */
trans = btrfs_start_transaction(root, 1);
btrfs_commit_transaction(trans, root);
ret = btrfs_write_and_wait_transaction(NULL, root);
BUG_ON(ret);
write_ctree_super(trans, root, root->fs_info->disk_super);
drop_cache(root);
write_ctree_super(NULL, root);
if (root->node)
btrfs_block_release(root, root->node);
......
......@@ -28,14 +28,14 @@ int dirty_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
struct buffer_head *buf);
int clean_tree_block(struct btrfs_trans_handle *trans,
struct btrfs_root *root, struct buffer_head *buf);
int btrfs_commit_transaction(struct btrfs_trans_handle *trans, struct btrfs_root
*root, struct btrfs_super_block *s);
int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
struct btrfs_root *root);
struct btrfs_root *open_ctree(struct super_block *sb,
struct buffer_head *sb_buffer,
struct btrfs_super_block *disk_super);
int close_ctree(struct btrfs_root *root);
void btrfs_block_release(struct btrfs_root *root, struct buffer_head *buf);
int write_ctree_super(struct btrfs_trans_handle *trans, struct btrfs_root *root,
struct btrfs_super_block *s);
int write_ctree_super(struct btrfs_trans_handle *trans,
struct btrfs_root *root);
int mkfs(int fd, u64 num_blocks, u32 blocksize);
#endif
......@@ -141,7 +141,6 @@ static void btrfs_read_locked_inode(struct inode *inode)
struct btrfs_inode_item *inode_item;
struct btrfs_root *root = btrfs_sb(inode->i_sb);
int ret;
printk("read locked inode %lu\n", inode->i_ino);
btrfs_init_path(&path);
ret = btrfs_lookup_inode(NULL, root, &path, inode->i_ino, 0);
if (ret) {
......@@ -152,7 +151,6 @@ printk("read locked inode %lu\n", inode->i_ino);
path.slots[0],
struct btrfs_inode_item);
printk("found locked inode %lu\n", inode->i_ino);
inode->i_mode = btrfs_inode_mode(inode_item);
inode->i_nlink = btrfs_inode_nlink(inode_item);
inode->i_uid = btrfs_inode_uid(inode_item);
......@@ -166,7 +164,6 @@ printk("found locked inode %lu\n", inode->i_ino);
inode->i_ctime.tv_nsec = btrfs_timespec_nsec(&inode_item->ctime);
inode->i_blocks = btrfs_inode_nblocks(inode_item);
inode->i_generation = btrfs_inode_generation(inode_item);
printk("about to release\n");
btrfs_release_path(root, &path);
switch (inode->i_mode & S_IFMT) {
#if 0
......@@ -176,19 +173,15 @@ printk("about to release\n");
break;
#endif
case S_IFREG:
printk("inode %lu now a file\n", inode->i_ino);
break;
case S_IFDIR:
printk("inode %lu now a directory\n", inode->i_ino);
inode->i_op = &btrfs_dir_inode_operations;
inode->i_fop = &btrfs_dir_file_operations;
break;
case S_IFLNK:
printk("inode %lu now a link\n", inode->i_ino);
// inode->i_op = &page_symlink_inode_operations;
break;
}
printk("returning!\n");
return;
}
......@@ -232,7 +225,6 @@ static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
return ERR_PTR(ret);
inode = NULL;
if (ino) {
printk("lookup on %.*s returns %lu\n", dentry->d_name.len, dentry->d_name.name, ino);
inode = iget(dir->i_sb, ino);
if (!inode)
return ERR_PTR(-EACCES);
......@@ -257,7 +249,6 @@ static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
int over;
key.objectid = inode->i_ino;
printk("readdir on dir %Lu pos %Lu\n", key.objectid, filp->f_pos);
key.flags = 0;
btrfs_set_key_type(&key, BTRFS_DIR_ITEM_KEY);
key.offset = filp->f_pos;
......@@ -266,15 +257,12 @@ printk("readdir on dir %Lu pos %Lu\n", key.objectid, filp->f_pos);
if (ret < 0) {
goto err;
}
printk("first ret %d\n", ret);
advance = filp->f_pos > 0 && ret != 0;
while(1) {
leaf = btrfs_buffer_leaf(path.nodes[0]);
nritems = btrfs_header_nritems(&leaf->header);
slot = path.slots[0];
printk("leaf %Lu nritems %lu slot %d\n", path.nodes[0]->b_blocknr, nritems, slot);
if (advance) {
printk("advancing!\n");
if (slot == nritems -1) {
ret = btrfs_next_leaf(root, &path);
if (ret)
......@@ -282,7 +270,6 @@ printk("advancing!\n");
leaf = btrfs_buffer_leaf(path.nodes[0]);
nritems = btrfs_header_nritems(&leaf->header);
slot = path.slots[0];
printk("2leaf %Lu nritems %lu slot %d\n", path.nodes[0]->b_blocknr, nritems, slot);
} else {
slot++;
path.slots[0]++;
......@@ -290,15 +277,11 @@ printk("2leaf %Lu nritems %lu slot %d\n", path.nodes[0]->b_blocknr, nritems, slo
}
advance = 1;
item = leaf->items + slot;
printk("item key %Lu %u %Lu\n", btrfs_disk_key_objectid(&item->key),
btrfs_disk_key_flags(&item->key), btrfs_disk_key_offset(&item->key));
if (btrfs_disk_key_objectid(&item->key) != key.objectid)
break;
if (btrfs_disk_key_type(&item->key) != BTRFS_DIR_ITEM_KEY)
continue;
di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
printk("filldir name %.*s, objectid %Lu\n", btrfs_dir_name_len(di),
(const char *)(di + 1), btrfs_dir_objectid(di));
over = filldir(dirent, (const char *)(di + 1),
btrfs_dir_name_len(di),
btrfs_disk_key_offset(&item->key),
......@@ -307,7 +290,6 @@ printk("filldir name %.*s, objectid %Lu\n", btrfs_dir_name_len(di),
break;
filp->f_pos = btrfs_disk_key_offset(&item->key) + 1;
}
printk("filldir all done\n");
ret = 0;
err:
btrfs_release_path(root, &path);
......
#include <linux/module.h>
#include <linux/fs.h>
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
static void put_transaction(struct btrfs_transaction *transaction)
{
transaction->use_count--;
if (transaction->use_count == 0)
kfree(transaction);
}
static int join_transaction(struct btrfs_root *root)
{
struct btrfs_transaction *cur_trans;
cur_trans = root->fs_info->running_transaction;
if (!cur_trans) {
cur_trans = kmalloc(sizeof(*cur_trans), GFP_NOFS);
BUG_ON(!cur_trans);
root->fs_info->running_transaction = cur_trans;
cur_trans->num_writers = 0;
cur_trans->transid = root->root_key.offset + 1;
init_waitqueue_head(&cur_trans->writer_wait);
init_waitqueue_head(&cur_trans->commit_wait);
cur_trans->in_commit = 0;
cur_trans->use_count = 0;
cur_trans->commit_done = 0;
}
cur_trans->num_writers++;
return 0;
}
struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,
int num_blocks)
{
struct btrfs_trans_handle *h = kmalloc(sizeof(*h), GFP_NOFS);
int ret;
mutex_lock(&root->fs_info->trans_mutex);
ret = join_transaction(root);
BUG_ON(ret);
h->transid = root->fs_info->running_transaction->transid;
h->transaction = root->fs_info->running_transaction;
h->blocks_reserved = num_blocks;
h->blocks_used = 0;
root->fs_info->running_transaction->use_count++;
mutex_unlock(&root->fs_info->trans_mutex);
return h;
}
int btrfs_end_transaction(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{
struct btrfs_transaction *cur_trans;
mutex_lock(&root->fs_info->trans_mutex);
cur_trans = root->fs_info->running_transaction;
WARN_ON(cur_trans->num_writers <= 1);
if (waitqueue_active(&cur_trans->writer_wait))
wake_up(&cur_trans->writer_wait);
cur_trans->num_writers--;
put_transaction(cur_trans);
mutex_unlock(&root->fs_info->trans_mutex);
kfree(trans);
return 0;
}
int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{
filemap_write_and_wait(root->fs_info->sb->s_bdev->bd_inode->i_mapping);
return 0;
}
int btrfs_commit_tree_roots(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{
int ret;
u64 old_extent_block;
struct btrfs_fs_info *fs_info = root->fs_info;
struct btrfs_root *tree_root = fs_info->tree_root;
struct btrfs_root *extent_root = fs_info->extent_root;
struct btrfs_root *inode_root = fs_info->inode_root;
btrfs_set_root_blocknr(&inode_root->root_item,
inode_root->node->b_blocknr);
ret = btrfs_update_root(trans, tree_root,
&inode_root->root_key,
&inode_root->root_item);
BUG_ON(ret);
while(1) {
old_extent_block = btrfs_root_blocknr(&extent_root->root_item);
if (old_extent_block == extent_root->node->b_blocknr)
break;
btrfs_set_root_blocknr(&extent_root->root_item,
extent_root->node->b_blocknr);
ret = btrfs_update_root(trans, tree_root,
&extent_root->root_key,
&extent_root->root_item);
BUG_ON(ret);
}
return 0;
}
static int wait_for_commit(struct btrfs_root *root,
struct btrfs_transaction *commit)
{
DEFINE_WAIT(wait);
commit->use_count++;
while(!commit->commit_done) {
prepare_to_wait(&commit->commit_wait, &wait,
TASK_UNINTERRUPTIBLE);
if (commit->commit_done)
break;
mutex_unlock(&root->fs_info->trans_mutex);
schedule();
mutex_lock(&root->fs_info->trans_mutex);
}
finish_wait(&commit->commit_wait, &wait);
return 0;
}
int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{
int ret = 0;
struct buffer_head *snap = root->commit_root;
struct btrfs_key snap_key;
struct btrfs_transaction *cur_trans;
DEFINE_WAIT(wait);
mutex_lock(&root->fs_info->trans_mutex);
if (trans->transaction->in_commit) {
cur_trans = trans->transaction;
trans->transaction->use_count++;
btrfs_end_transaction(trans, root);
ret = wait_for_commit(root, cur_trans);
BUG_ON(ret);
put_transaction(cur_trans);
mutex_unlock(&root->fs_info->trans_mutex);
return 0;
}
while (trans->transaction->num_writers > 1) {
prepare_to_wait(&trans->transaction->writer_wait, &wait,
TASK_UNINTERRUPTIBLE);
if (trans->transaction->num_writers <= 1)
break;
mutex_unlock(&root->fs_info->trans_mutex);
schedule();
mutex_lock(&root->fs_info->trans_mutex);
}
finish_wait(&trans->transaction->writer_wait, &wait);
cur_trans = root->fs_info->running_transaction;
root->fs_info->running_transaction = NULL;
mutex_unlock(&root->fs_info->trans_mutex);
memcpy(&snap_key, &root->root_key, sizeof(snap_key));
root->root_key.offset++;
if (btrfs_root_blocknr(&root->root_item) != root->node->b_blocknr) {
btrfs_set_root_blocknr(&root->root_item, root->node->b_blocknr);
ret = btrfs_insert_root(trans, root->fs_info->tree_root,
&root->root_key, &root->root_item);
BUG_ON(ret);
}
ret = btrfs_commit_tree_roots(trans, root);
BUG_ON(ret);
ret = btrfs_write_and_wait_transaction(trans, root);
BUG_ON(ret);
write_ctree_super(trans, root);
btrfs_finish_extent_commit(trans, root->fs_info->extent_root);
btrfs_finish_extent_commit(trans, root->fs_info->tree_root);
put_transaction(cur_trans);
kfree(trans);
if (root->node != root->commit_root) {
trans = btrfs_start_transaction(root, 1);
root->commit_root = root->node;
get_bh(root->node);
ret = btrfs_drop_snapshot(trans, root, snap);
BUG_ON(ret);
ret = btrfs_del_root(trans, root->fs_info->tree_root,
&snap_key);
BUG_ON(ret);
root->fs_info->generation = root->root_key.offset + 1;
ret = btrfs_end_transaction(trans, root);
BUG_ON(ret);
}
return ret;
}
#ifndef __TRANSACTION__
#define __TRANSACTION__
struct btrfs_transaction {
u64 transid;
unsigned long num_writers;
int in_commit;
int use_count;
int commit_done;
wait_queue_head_t writer_wait;
wait_queue_head_t commit_wait;
};
struct btrfs_trans_handle {
u64 transid;
unsigned long blocks_reserved;
unsigned long blocks_used;
struct btrfs_transaction *transaction;
};
static inline struct btrfs_trans_handle *
btrfs_start_transaction(struct btrfs_root *root, int num_blocks)
{
struct btrfs_trans_handle *h = kmalloc(sizeof(*h), GFP_NOFS);
h->transid = root->root_key.offset;
h->blocks_reserved = num_blocks;
h->blocks_used = 0;
return h;
}
static inline void btrfs_free_transaction(struct btrfs_root *root,
struct btrfs_trans_handle *handle)
{
memset(handle, 0, sizeof(*handle));
kfree(handle);
}
int btrfs_end_transaction(struct btrfs_trans_handle *trans,
struct btrfs_root *root);
struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,
int num_blocks);
int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans,
struct btrfs_root *root);
int btrfs_commit_tree_roots(struct btrfs_trans_handle *trans,
struct btrfs_root *root);
#endif
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