Commit 090d1875 authored by Chris Mason's avatar Chris Mason Committed by David Woodhouse

Btrfs: directory readahead

Signed-off-by: default avatarChris Mason <chris.mason@oracle.com>
parent 31f3c99b
......@@ -5,6 +5,7 @@
#include <linux/scatterlist.h>
#include <linux/swap.h>
#include <linux/radix-tree.h>
#include <linux/file.h>
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
......@@ -253,6 +254,29 @@ static struct address_space_operations btree_aops = {
.sync_page = block_sync_page,
};
int readahead_tree_block(struct btrfs_root *root, u64 blocknr)
{
struct buffer_head *bh = NULL;
bh = btrfs_find_create_tree_block(root, blocknr);
if (!bh)
return 0;
if (buffer_uptodate(bh))
goto done;
if (test_set_buffer_locked(bh))
goto done;
if (!buffer_uptodate(bh)) {
get_bh(bh);
bh->b_end_io = end_buffer_read_sync;
submit_bh(READ, bh);
} else {
unlock_buffer(bh);
}
done:
brelse(bh);
return 0;
}
struct buffer_head *read_tree_block(struct btrfs_root *root, u64 blocknr)
{
struct buffer_head *bh = NULL;
......@@ -270,11 +294,14 @@ struct buffer_head *read_tree_block(struct btrfs_root *root, u64 blocknr)
wait_on_buffer(bh);
if (!buffer_uptodate(bh))
goto fail;
csum_tree_block(root, bh, 1);
} else {
unlock_buffer(bh);
}
uptodate:
if (!buffer_checked(bh)) {
csum_tree_block(root, bh, 1);
set_buffer_checked(bh);
}
if (check_tree_block(root, bh))
BUG();
return bh;
......
......@@ -5,6 +5,11 @@
#define BTRFS_SUPER_INFO_OFFSET (16 * 1024)
enum btrfs_bh_state_bits {
BH_Checked = BH_PrivateStart,
};
BUFFER_FNS(Checked, checked);
static inline struct btrfs_node *btrfs_buffer_node(struct buffer_head *bh)
{
return (struct btrfs_node *)bh->b_data;
......@@ -21,6 +26,7 @@ static inline struct btrfs_header *btrfs_buffer_header(struct buffer_head *bh)
}
struct buffer_head *read_tree_block(struct btrfs_root *root, u64 blocknr);
int readahead_tree_block(struct btrfs_root *root, u64 blocknr);
struct buffer_head *btrfs_find_create_tree_block(struct btrfs_root *root,
u64 blocknr);
int write_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
......
......@@ -812,6 +812,7 @@ struct buffer_head *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
BUG_ON(ret);
buf = btrfs_find_create_tree_block(root, ins.objectid);
set_buffer_uptodate(buf);
set_buffer_checked(buf);
set_radix_bit(&trans->transaction->dirty_pages, buf->b_page->index);
return buf;
}
......
......@@ -585,6 +585,31 @@ printk("adding new root for inode %lu root %p (found %p)\n", inode->i_ino, sub_r
return d_splice_alias(inode, dentry);
}
static void reada_leaves(struct btrfs_root *root, struct btrfs_path *path)
{
struct btrfs_node *node;
int i;
int nritems;
u64 objectid;
u64 item_objectid;
u64 blocknr;
int slot;
if (!path->nodes[1])
return;
node = btrfs_buffer_node(path->nodes[1]);
slot = path->slots[1];
objectid = btrfs_disk_key_objectid(&node->ptrs[slot].key);
nritems = btrfs_header_nritems(&node->header);
for (i = slot; i < nritems; i++) {
item_objectid = btrfs_disk_key_objectid(&node->ptrs[i].key);
if (item_objectid != objectid)
break;
blocknr = btrfs_node_blockptr(node, i);
readahead_tree_block(root, blocknr);
}
}
static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
{
struct inode *inode = filp->f_path.dentry->d_inode;
......@@ -619,6 +644,7 @@ static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
if (ret < 0)
goto err;
advance = 0;
reada_leaves(root, path);
while(1) {
leaf = btrfs_buffer_leaf(path->nodes[0]);
nritems = btrfs_header_nritems(&leaf->header);
......@@ -631,6 +657,8 @@ static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
leaf = btrfs_buffer_leaf(path->nodes[0]);
nritems = btrfs_header_nritems(&leaf->header);
slot = path->slots[0];
if (path->slots[1] == 0)
reada_leaves(root, path);
} else {
slot++;
path->slots[0]++;
......
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