/**
* aops.c - NTFS kernel address space operations and page cache handling.
* Part of the Linux-NTFS project.
*
* Copyright (c) 2001-2007 Anton Altaparmakov
* Copyright (c) 2002 Richard Russon
*
* This program/include file 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/include file 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 (in the main directory of the Linux-NTFS
* distribution in the file COPYING); if not, write to the Free Software
* Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/pagemap.h>
#include <linux/swap.h>
#include <linux/buffer_head.h>
#include <linux/writeback.h>
#include <linux/bit_spinlock.h>
#include "aops.h"
#include "attrib.h"
#include "debug.h"
#include "inode.h"
#include "mft.h"
#include "runlist.h"
#include "types.h"
#include "ntfs.h"
/**
* ntfs_end_buffer_async_read - async io completion for reading attributes
* @bh: buffer head on which io is completed
* @uptodate: whether @bh is now uptodate or not
*
* Asynchronous I/O completion handler for reading pages belonging to the
* attribute address space of an inode. The inodes can either be files or
* directories or they can be fake inodes describing some attribute.
*
* If NInoMstProtected(), perform the post read mst fixups when all IO on the
* page has been completed and mark the page uptodate or set the error bit on
* the page. To determine the size of the records that need fixing up, we
* cheat a little bit by setting the index_block_size in ntfs_inode to the ntfs
* record size, and index_block_size_bits, to the log(base 2) of the ntfs
* record size.
*/
static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate)
{
unsigned long flags;
struct buffer_head *first, *tmp;
struct page *page;
struct inode *vi;
ntfs_inode *ni;
int page_uptodate = 1;
page = bh->b_page;
vi = page->mapping->host;
ni = NTFS_I(vi);
if (likely(uptodate)) {
loff_t i_size;
s64 file_ofs, init_size;
set_buffer_uptodate(bh);
file_ofs = ((s64)page->index << PAGE_CACHE_SHIFT) +
bh_offset(bh);
read_lock_irqsave(&ni->size_lock, flags);
init_size = ni->initialized_size;
i_size = i_size_read(vi);
read_unlock_irqrestore(&ni->size_lock, flags);
if (unlikely(init_size > i_size)) {
/* Race with shrinking truncate. */
init_size = i_size;
}
/* Check for the current buffer head overflowing. */
if (unlikely(file_ofs + bh->b_size > init_size)) {
int ofs;
void *kaddr;
ofs = 0;
if (file_ofs < init_size)
ofs = init_size - file_ofs;
local_irq_save(flags);
kaddr = kmap_atomic(page, KM_BIO_SRC_IRQ);
memset(kaddr + bh_offset(bh) + ofs, 0,
bh->b_size - ofs);
flush_dcache_page(page);
kunmap_atomic(kaddr, KM_BIO_SRC_IRQ);
local_irq_restore(flags);
}
} else {
clear_buffer_uptodate(bh);
SetPageError(page);
ntfs_error(ni->vol->sb, "Buffer I/O error, logical block "
"0x%llx.", (unsigned long long)bh->b_
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