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/*-
* Copyright (c) 2010 Zheng Liu <lz@freebsd.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/types.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/vnode.h>
#include <sys/bio.h>
#include <sys/buf.h>
#include <sys/conf.h>
#include <fs/ext2fs/ext2_mount.h>
#include <fs/ext2fs/fs.h>
#include <fs/ext2fs/inode.h>
#include <fs/ext2fs/ext2fs.h>
#include <fs/ext2fs/ext2_extents.h>
#include <fs/ext2fs/ext2_extern.h>
static void ext4_ext_binsearch_index(struct inode *ip, struct ext4_extent_path
*path, daddr_t lbn)
{
struct ext4_extent_header *ehp = path->ep_header;
struct ext4_extent_index *l, *r, *m;
l = (struct ext4_extent_index *)(char *)(ehp + 1);
r = (struct ext4_extent_index *)(char *)(ehp + 1) + ehp->eh_ecount - 1;
while (l <= r) {
m = l + (r - l) / 2;
if (lbn < m->ei_blk)
r = m - 1;
else
l = m + 1;
}
path->ep_index = l - 1;
}
static void
ext4_ext_binsearch(struct inode *ip, struct ext4_extent_path *path, daddr_t lbn)
{
struct ext4_extent_header *ehp = path->ep_header;
struct ext4_extent *l, *r, *m;
if (ehp->eh_ecount == 0)
return;
l = (struct ext4_extent *)(char *)(ehp + 1);
r = (struct ext4_extent *)(char *)(ehp + 1) + ehp->eh_ecount - 1;
while (l <= r) {
m = l + (r - l) / 2;
if (lbn < m->e_blk)
r = m - 1;
else
l = m + 1;
}
path->ep_ext = l - 1;
}
/*
* Find a block in ext4 extent cache.
*/
int
ext4_ext_in_cache(struct inode *ip, daddr_t lbn, struct ext4_extent *ep)
{
struct ext4_extent_cache *ecp;
int ret = EXT4_EXT_CACHE_NO;
ecp = &ip->i_ext_cache;
/* cache is invalid */
if (ecp->ec_type == EXT4_EXT_CACHE_NO)
return (ret);
if (lbn >= ecp->ec_blk && lbn < ecp->ec_blk + ecp->ec_len) {
ep->e_blk = ecp->ec_blk;
ep->e_start_lo = ecp->ec_start & 0xffffffff;
ep->e_start_hi = ecp->ec_start >> 32 & 0xffff;
ep->e_len = ecp->ec_len;
ret = ecp->ec_type;
}
return (ret);
}
/*
* Put an ext4_extent structure in ext4 cache.
*/
void
ext4_ext_put_cache(struct inode *ip, struct ext4_extent *ep, int type)
{
struct ext4_extent_cache *ecp;
ecp = &ip->i_ext_cache;
ecp->ec_type = type;
ecp->ec_blk = ep->e_blk;
ecp->ec_len = ep->e_len;
ecp->ec_start = (daddr_t)ep->e_start_hi << 32 | ep->e_start_lo;
}
/*
* Find an extent.
*/
struct ext4_extent_path *
ext4_ext_find_extent(struct m_ext2fs *fs, struct inode *ip,
daddr_t lbn, struct ext4_extent_path *path)
{
struct ext4_extent_header *ehp;
uint16_t i;
int error, size;
daddr_t nblk;
ehp = (struct ext4_extent_header *)(char *)ip->i_db;
if (ehp->eh_magic != EXT4_EXT_MAGIC)
return (NULL);
path->ep_header = ehp;
for (i = ehp->eh_depth; i != 0; --i) {
ext4_ext_binsearch_index(ip, path, lbn);
path->ep_depth = 0;
path->ep_ext = NULL;
nblk = (daddr_t)path->ep_index->ei_leaf_hi << 32 |
path->ep_index->ei_leaf_lo;
size = blksize(fs, ip, nblk);
if (path->ep_bp != NULL) {
brelse(path->ep_bp);
path->ep_bp = NULL;
}
error = bread(ip->i_devvp, fsbtodb(fs, nblk), size, NOCRED,
&path->ep_bp);
if (error) {
brelse(path->ep_bp);
path->ep_bp = NULL;
return (NULL);
}
ehp = (struct ext4_extent_header *)path->ep_bp->b_data;
path->ep_header = ehp;
}
path->ep_depth = i;
path->ep_ext = NULL;
path->ep_index = NULL;
ext4_ext_binsearch(ip, path, lbn);
return (path);
}
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