mirror of
https://github.com/torvalds/linux.git
synced 2024-11-24 21:21:41 +00:00
nilfs2: B-tree node cache
This adds routines for B-tree node buffers. Signed-off-by: Seiji Kihara <kihara.seiji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Ryusuke Konishi
Linus Torvalds
parent
36a580eb48
commit
a60be987d4
316
fs/nilfs2/btnode.c
Normal file
316
fs/nilfs2/btnode.c
Normal file
@ -0,0 +1,316 @@
|
||||
/*
|
||||
* btnode.c - NILFS B-tree node cache
|
||||
*
|
||||
* Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify
|
||||
* it under the terms of the GNU General Public License as published by
|
||||
* the Free Software Foundation; either version 2 of the License, or
|
||||
* (at your option) any later version.
|
||||
*
|
||||
* This program is distributed in the hope that it will be useful,
|
||||
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
* GNU General Public License for more details.
|
||||
*
|
||||
* You should have received a copy of the GNU General Public License
|
||||
* along with this program; if not, write to the Free Software
|
||||
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
||||
*
|
||||
* This file was originally written by Seiji Kihara <kihara@osrg.net>
|
||||
* and fully revised by Ryusuke Konishi <ryusuke@osrg.net> for
|
||||
* stabilization and simplification.
|
||||
*
|
||||
*/
|
||||
|
||||
#include <linux/types.h>
|
||||
#include <linux/buffer_head.h>
|
||||
#include <linux/mm.h>
|
||||
#include <linux/backing-dev.h>
|
||||
#include "nilfs.h"
|
||||
#include "mdt.h"
|
||||
#include "dat.h"
|
||||
#include "page.h"
|
||||
#include "btnode.h"
|
||||
|
||||
|
||||
void nilfs_btnode_cache_init_once(struct address_space *btnc)
|
||||
{
|
||||
INIT_RADIX_TREE(&btnc->page_tree, GFP_ATOMIC);
|
||||
spin_lock_init(&btnc->tree_lock);
|
||||
INIT_LIST_HEAD(&btnc->private_list);
|
||||
spin_lock_init(&btnc->private_lock);
|
||||
|
||||
spin_lock_init(&btnc->i_mmap_lock);
|
||||
INIT_RAW_PRIO_TREE_ROOT(&btnc->i_mmap);
|
||||
INIT_LIST_HEAD(&btnc->i_mmap_nonlinear);
|
||||
}
|
||||
|
||||
static struct address_space_operations def_btnode_aops;
|
||||
|
||||
void nilfs_btnode_cache_init(struct address_space *btnc)
|
||||
{
|
||||
btnc->host = NULL; /* can safely set to host inode ? */
|
||||
btnc->flags = 0;
|
||||
mapping_set_gfp_mask(btnc, GFP_NOFS);
|
||||
btnc->assoc_mapping = NULL;
|
||||
btnc->backing_dev_info = &default_backing_dev_info;
|
||||
btnc->a_ops = &def_btnode_aops;
|
||||
}
|
||||
|
||||
void nilfs_btnode_cache_clear(struct address_space *btnc)
|
||||
{
|
||||
invalidate_mapping_pages(btnc, 0, -1);
|
||||
truncate_inode_pages(btnc, 0);
|
||||
}
|
||||
|
||||
int nilfs_btnode_submit_block(struct address_space *btnc, __u64 blocknr,
|
||||
sector_t pblocknr, struct buffer_head **pbh,
|
||||
int newblk)
|
||||
{
|
||||
struct buffer_head *bh;
|
||||
struct inode *inode = NILFS_BTNC_I(btnc);
|
||||
int err;
|
||||
|
||||
bh = nilfs_grab_buffer(inode, btnc, blocknr, 1 << BH_NILFS_Node);
|
||||
if (unlikely(!bh))
|
||||
return -ENOMEM;
|
||||
|
||||
err = -EEXIST; /* internal code */
|
||||
if (newblk) {
|
||||
if (unlikely(buffer_mapped(bh) || buffer_uptodate(bh) ||
|
||||
buffer_dirty(bh))) {
|
||||
brelse(bh);
|
||||
BUG();
|
||||
}
|
||||
bh->b_bdev = NILFS_I_NILFS(inode)->ns_bdev;
|
||||
bh->b_blocknr = blocknr;
|
||||
set_buffer_mapped(bh);
|
||||
set_buffer_uptodate(bh);
|
||||
goto found;
|
||||
}
|
||||
|
||||
if (buffer_uptodate(bh) || buffer_dirty(bh))
|
||||
goto found;
|
||||
|
||||
if (pblocknr == 0) {
|
||||
pblocknr = blocknr;
|
||||
if (inode->i_ino != NILFS_DAT_INO) {
|
||||
struct inode *dat =
|
||||
nilfs_dat_inode(NILFS_I_NILFS(inode));
|
||||
|
||||
/* blocknr is a virtual block number */
|
||||
err = nilfs_dat_translate(dat, blocknr, &pblocknr);
|
||||
if (unlikely(err)) {
|
||||
brelse(bh);
|
||||
goto out_locked;
|
||||
}
|
||||
}
|
||||
}
|
||||
lock_buffer(bh);
|
||||
if (buffer_uptodate(bh)) {
|
||||
unlock_buffer(bh);
|
||||
err = -EEXIST; /* internal code */
|
||||
goto found;
|
||||
}
|
||||
set_buffer_mapped(bh);
|
||||
bh->b_bdev = NILFS_I_NILFS(inode)->ns_bdev;
|
||||
bh->b_blocknr = pblocknr; /* set block address for read */
|
||||
bh->b_end_io = end_buffer_read_sync;
|
||||
get_bh(bh);
|
||||
submit_bh(READ, bh);
|
||||
bh->b_blocknr = blocknr; /* set back to the given block address */
|
||||
err = 0;
|
||||
found:
|
||||
*pbh = bh;
|
||||
|
||||
out_locked:
|
||||
unlock_page(bh->b_page);
|
||||
page_cache_release(bh->b_page);
|
||||
return err;
|
||||
}
|
||||
|
||||
int nilfs_btnode_get(struct address_space *btnc, __u64 blocknr,
|
||||
sector_t pblocknr, struct buffer_head **pbh, int newblk)
|
||||
{
|
||||
struct buffer_head *bh;
|
||||
int err;
|
||||
|
||||
err = nilfs_btnode_submit_block(btnc, blocknr, pblocknr, pbh, newblk);
|
||||
if (err == -EEXIST) /* internal code (cache hit) */
|
||||
return 0;
|
||||
if (unlikely(err))
|
||||
return err;
|
||||
|
||||
bh = *pbh;
|
||||
wait_on_buffer(bh);
|
||||
if (!buffer_uptodate(bh)) {
|
||||
brelse(bh);
|
||||
return -EIO;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* nilfs_btnode_delete - delete B-tree node buffer
|
||||
* @bh: buffer to be deleted
|
||||
*
|
||||
* nilfs_btnode_delete() invalidates the specified buffer and delete the page
|
||||
* including the buffer if the page gets unbusy.
|
||||
*/
|
||||
void nilfs_btnode_delete(struct buffer_head *bh)
|
||||
{
|
||||
struct address_space *mapping;
|
||||
struct page *page = bh->b_page;
|
||||
pgoff_t index = page_index(page);
|
||||
int still_dirty;
|
||||
|
||||
page_cache_get(page);
|
||||
lock_page(page);
|
||||
wait_on_page_writeback(page);
|
||||
|
||||
nilfs_forget_buffer(bh);
|
||||
still_dirty = PageDirty(page);
|
||||
mapping = page->mapping;
|
||||
unlock_page(page);
|
||||
page_cache_release(page);
|
||||
|
||||
if (!still_dirty && mapping)
|
||||
invalidate_inode_pages2_range(mapping, index, index);
|
||||
}
|
||||
|
||||
/**
|
||||
* nilfs_btnode_prepare_change_key
|
||||
* prepare to move contents of the block for old key to one of new key.
|
||||
* the old buffer will not be removed, but might be reused for new buffer.
|
||||
* it might return -ENOMEM because of memory allocation errors,
|
||||
* and might return -EIO because of disk read errors.
|
||||
*/
|
||||
int nilfs_btnode_prepare_change_key(struct address_space *btnc,
|
||||
struct nilfs_btnode_chkey_ctxt *ctxt)
|
||||
{
|
||||
struct buffer_head *obh, *nbh;
|
||||
struct inode *inode = NILFS_BTNC_I(btnc);
|
||||
__u64 oldkey = ctxt->oldkey, newkey = ctxt->newkey;
|
||||
int err;
|
||||
|
||||
if (oldkey == newkey)
|
||||
return 0;
|
||||
|
||||
obh = ctxt->bh;
|
||||
ctxt->newbh = NULL;
|
||||
|
||||
if (inode->i_blkbits == PAGE_CACHE_SHIFT) {
|
||||
lock_page(obh->b_page);
|
||||
/*
|
||||
* We cannot call radix_tree_preload for the kernels older
|
||||
* than 2.6.23, because it is not exported for modules.
|
||||
*/
|
||||
err = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
|
||||
if (err)
|
||||
goto failed_unlock;
|
||||
/* BUG_ON(oldkey != obh->b_page->index); */
|
||||
if (unlikely(oldkey != obh->b_page->index))
|
||||
NILFS_PAGE_BUG(obh->b_page,
|
||||
"invalid oldkey %lld (newkey=%lld)",
|
||||
(unsigned long long)oldkey,
|
||||
(unsigned long long)newkey);
|
||||
|
||||
retry:
|
||||
spin_lock_irq(&btnc->tree_lock);
|
||||
err = radix_tree_insert(&btnc->page_tree, newkey, obh->b_page);
|
||||
spin_unlock_irq(&btnc->tree_lock);
|
||||
/*
|
||||
* Note: page->index will not change to newkey until
|
||||
* nilfs_btnode_commit_change_key() will be called.
|
||||
* To protect the page in intermediate state, the page lock
|
||||
* is held.
|
||||
*/
|
||||
radix_tree_preload_end();
|
||||
if (!err)
|
||||
return 0;
|
||||
else if (err != -EEXIST)
|
||||
goto failed_unlock;
|
||||
|
||||
err = invalidate_inode_pages2_range(btnc, newkey, newkey);
|
||||
if (!err)
|
||||
goto retry;
|
||||
/* fallback to copy mode */
|
||||
unlock_page(obh->b_page);
|
||||
}
|
||||
|
||||
err = nilfs_btnode_get(btnc, newkey, 0, &nbh, 1);
|
||||
if (likely(!err)) {
|
||||
BUG_ON(nbh == obh);
|
||||
ctxt->newbh = nbh;
|
||||
}
|
||||
return err;
|
||||
|
||||
failed_unlock:
|
||||
unlock_page(obh->b_page);
|
||||
return err;
|
||||
}
|
||||
|
||||
/**
|
||||
* nilfs_btnode_commit_change_key
|
||||
* commit the change_key operation prepared by prepare_change_key().
|
||||
*/
|
||||
void nilfs_btnode_commit_change_key(struct address_space *btnc,
|
||||
struct nilfs_btnode_chkey_ctxt *ctxt)
|
||||
{
|
||||
struct buffer_head *obh = ctxt->bh, *nbh = ctxt->newbh;
|
||||
__u64 oldkey = ctxt->oldkey, newkey = ctxt->newkey;
|
||||
struct page *opage;
|
||||
|
||||
if (oldkey == newkey)
|
||||
return;
|
||||
|
||||
if (nbh == NULL) { /* blocksize == pagesize */
|
||||
opage = obh->b_page;
|
||||
if (unlikely(oldkey != opage->index))
|
||||
NILFS_PAGE_BUG(opage,
|
||||
"invalid oldkey %lld (newkey=%lld)",
|
||||
(unsigned long long)oldkey,
|
||||
(unsigned long long)newkey);
|
||||
if (!test_set_buffer_dirty(obh) && TestSetPageDirty(opage))
|
||||
BUG();
|
||||
|
||||
spin_lock_irq(&btnc->tree_lock);
|
||||
radix_tree_delete(&btnc->page_tree, oldkey);
|
||||
radix_tree_tag_set(&btnc->page_tree, newkey,
|
||||
PAGECACHE_TAG_DIRTY);
|
||||
spin_unlock_irq(&btnc->tree_lock);
|
||||
|
||||
opage->index = obh->b_blocknr = newkey;
|
||||
unlock_page(opage);
|
||||
} else {
|
||||
nilfs_copy_buffer(nbh, obh);
|
||||
nilfs_btnode_mark_dirty(nbh);
|
||||
|
||||
nbh->b_blocknr = newkey;
|
||||
ctxt->bh = nbh;
|
||||
nilfs_btnode_delete(obh); /* will decrement bh->b_count */
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* nilfs_btnode_abort_change_key
|
||||
* abort the change_key operation prepared by prepare_change_key().
|
||||
*/
|
||||
void nilfs_btnode_abort_change_key(struct address_space *btnc,
|
||||
struct nilfs_btnode_chkey_ctxt *ctxt)
|
||||
{
|
||||
struct buffer_head *nbh = ctxt->newbh;
|
||||
__u64 oldkey = ctxt->oldkey, newkey = ctxt->newkey;
|
||||
|
||||
if (oldkey == newkey)
|
||||
return;
|
||||
|
||||
if (nbh == NULL) { /* blocksize == pagesize */
|
||||
spin_lock_irq(&btnc->tree_lock);
|
||||
radix_tree_delete(&btnc->page_tree, newkey);
|
||||
spin_unlock_irq(&btnc->tree_lock);
|
||||
unlock_page(ctxt->bh->b_page);
|
||||
} else
|
||||
brelse(nbh);
|
||||
}
|
||||
58
fs/nilfs2/btnode.h
Normal file
58
fs/nilfs2/btnode.h
Normal file
@ -0,0 +1,58 @@
|
||||
/*
|
||||
* btnode.h - NILFS B-tree node cache
|
||||
*
|
||||
* Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify
|
||||
* it under the terms of the GNU General Public License as published by
|
||||
* the Free Software Foundation; either version 2 of the License, or
|
||||
* (at your option) any later version.
|
||||
*
|
||||
* This program is distributed in the hope that it will be useful,
|
||||
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
* GNU General Public License for more details.
|
||||
*
|
||||
* You should have received a copy of the GNU General Public License
|
||||
* along with this program; if not, write to the Free Software
|
||||
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
||||
*
|
||||
* Written by Seiji Kihara <kihara@osrg.net>
|
||||
* Revised by Ryusuke Konishi <ryusuke@osrg.net>
|
||||
*/
|
||||
|
||||
#ifndef _NILFS_BTNODE_H
|
||||
#define _NILFS_BTNODE_H
|
||||
|
||||
#include <linux/types.h>
|
||||
#include <linux/buffer_head.h>
|
||||
#include <linux/fs.h>
|
||||
#include <linux/backing-dev.h>
|
||||
|
||||
|
||||
struct nilfs_btnode_chkey_ctxt {
|
||||
__u64 oldkey;
|
||||
__u64 newkey;
|
||||
struct buffer_head *bh;
|
||||
struct buffer_head *newbh;
|
||||
};
|
||||
|
||||
void nilfs_btnode_cache_init_once(struct address_space *);
|
||||
void nilfs_btnode_cache_init(struct address_space *);
|
||||
void nilfs_btnode_cache_clear(struct address_space *);
|
||||
int nilfs_btnode_submit_block(struct address_space *, __u64, sector_t,
|
||||
struct buffer_head **, int);
|
||||
int nilfs_btnode_get(struct address_space *, __u64, sector_t,
|
||||
struct buffer_head **, int);
|
||||
void nilfs_btnode_delete(struct buffer_head *);
|
||||
int nilfs_btnode_prepare_change_key(struct address_space *,
|
||||
struct nilfs_btnode_chkey_ctxt *);
|
||||
void nilfs_btnode_commit_change_key(struct address_space *,
|
||||
struct nilfs_btnode_chkey_ctxt *);
|
||||
void nilfs_btnode_abort_change_key(struct address_space *,
|
||||
struct nilfs_btnode_chkey_ctxt *);
|
||||
|
||||
#define nilfs_btnode_mark_dirty(bh) nilfs_mark_buffer_dirty(bh)
|
||||
|
||||
|
||||
#endif /* _NILFS_BTNODE_H */
|
||||
Loading…
Reference in New Issue
Block a user