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2840501ac8
As suggested by Robert P. J. Day <rpjday@mindspring.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com> Cc: Robert P. J. Day <rpjday@mindspring.com>
870 lines
22 KiB
C
870 lines
22 KiB
C
/*
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* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
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* Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
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*
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* This copyrighted material is made available to anyone wishing to use,
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* modify, copy, or redistribute it subject to the terms and conditions
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* of the GNU General Public License version 2.
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*/
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#include <linux/sched.h>
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#include <linux/slab.h>
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#include <linux/spinlock.h>
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#include <linux/completion.h>
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#include <linux/buffer_head.h>
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#include <linux/pagemap.h>
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#include <linux/pagevec.h>
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#include <linux/mpage.h>
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#include <linux/fs.h>
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#include <linux/writeback.h>
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#include <linux/gfs2_ondisk.h>
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#include <linux/lm_interface.h>
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#include "gfs2.h"
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#include "incore.h"
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#include "bmap.h"
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#include "glock.h"
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#include "inode.h"
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#include "log.h"
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#include "meta_io.h"
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#include "ops_address.h"
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#include "quota.h"
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#include "trans.h"
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#include "rgrp.h"
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#include "ops_file.h"
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#include "super.h"
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#include "util.h"
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#include "glops.h"
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static void gfs2_page_add_databufs(struct gfs2_inode *ip, struct page *page,
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unsigned int from, unsigned int to)
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{
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struct buffer_head *head = page_buffers(page);
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unsigned int bsize = head->b_size;
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struct buffer_head *bh;
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unsigned int start, end;
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for (bh = head, start = 0; bh != head || !start;
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bh = bh->b_this_page, start = end) {
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end = start + bsize;
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if (end <= from || start >= to)
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continue;
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if (gfs2_is_jdata(ip))
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set_buffer_uptodate(bh);
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gfs2_trans_add_bh(ip->i_gl, bh, 0);
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}
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}
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/**
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* gfs2_get_block - Fills in a buffer head with details about a block
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* @inode: The inode
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* @lblock: The block number to look up
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* @bh_result: The buffer head to return the result in
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* @create: Non-zero if we may add block to the file
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*
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* Returns: errno
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*/
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int gfs2_get_block(struct inode *inode, sector_t lblock,
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struct buffer_head *bh_result, int create)
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{
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return gfs2_block_map(inode, lblock, create, bh_result);
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}
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/**
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* gfs2_get_block_noalloc - Fills in a buffer head with details about a block
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* @inode: The inode
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* @lblock: The block number to look up
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* @bh_result: The buffer head to return the result in
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* @create: Non-zero if we may add block to the file
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*
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* Returns: errno
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*/
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static int gfs2_get_block_noalloc(struct inode *inode, sector_t lblock,
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struct buffer_head *bh_result, int create)
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{
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int error;
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error = gfs2_block_map(inode, lblock, 0, bh_result);
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if (error)
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return error;
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if (bh_result->b_blocknr == 0)
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return -EIO;
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return 0;
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}
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static int gfs2_get_block_direct(struct inode *inode, sector_t lblock,
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struct buffer_head *bh_result, int create)
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{
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return gfs2_block_map(inode, lblock, 0, bh_result);
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}
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/**
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* gfs2_writepage - Write complete page
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* @page: Page to write
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*
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* Returns: errno
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*
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* Some of this is copied from block_write_full_page() although we still
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* call it to do most of the work.
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*/
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static int gfs2_writepage(struct page *page, struct writeback_control *wbc)
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{
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struct inode *inode = page->mapping->host;
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struct gfs2_inode *ip = GFS2_I(inode);
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struct gfs2_sbd *sdp = GFS2_SB(inode);
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loff_t i_size = i_size_read(inode);
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pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
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unsigned offset;
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int error;
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int done_trans = 0;
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if (gfs2_assert_withdraw(sdp, gfs2_glock_is_held_excl(ip->i_gl))) {
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unlock_page(page);
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return -EIO;
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}
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if (current->journal_info)
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goto out_ignore;
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/* Is the page fully outside i_size? (truncate in progress) */
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offset = i_size & (PAGE_CACHE_SIZE-1);
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if (page->index > end_index || (page->index == end_index && !offset)) {
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page->mapping->a_ops->invalidatepage(page, 0);
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unlock_page(page);
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return 0; /* don't care */
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}
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if ((sdp->sd_args.ar_data == GFS2_DATA_ORDERED || gfs2_is_jdata(ip)) &&
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PageChecked(page)) {
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ClearPageChecked(page);
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error = gfs2_trans_begin(sdp, RES_DINODE + 1, 0);
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if (error)
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goto out_ignore;
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if (!page_has_buffers(page)) {
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create_empty_buffers(page, inode->i_sb->s_blocksize,
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(1 << BH_Dirty)|(1 << BH_Uptodate));
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}
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gfs2_page_add_databufs(ip, page, 0, sdp->sd_vfs->s_blocksize-1);
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done_trans = 1;
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}
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error = block_write_full_page(page, gfs2_get_block_noalloc, wbc);
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if (done_trans)
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gfs2_trans_end(sdp);
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gfs2_meta_cache_flush(ip);
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return error;
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out_ignore:
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redirty_page_for_writepage(wbc, page);
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unlock_page(page);
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return 0;
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}
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/**
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* gfs2_writepages - Write a bunch of dirty pages back to disk
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* @mapping: The mapping to write
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* @wbc: Write-back control
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*
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* For journaled files and/or ordered writes this just falls back to the
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* kernel's default writepages path for now. We will probably want to change
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* that eventually (i.e. when we look at allocate on flush).
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*
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* For the data=writeback case though we can already ignore buffer heads
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* and write whole extents at once. This is a big reduction in the
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* number of I/O requests we send and the bmap calls we make in this case.
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*/
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static int gfs2_writepages(struct address_space *mapping,
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struct writeback_control *wbc)
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{
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struct inode *inode = mapping->host;
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struct gfs2_inode *ip = GFS2_I(inode);
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struct gfs2_sbd *sdp = GFS2_SB(inode);
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if (sdp->sd_args.ar_data == GFS2_DATA_WRITEBACK && !gfs2_is_jdata(ip))
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return mpage_writepages(mapping, wbc, gfs2_get_block_noalloc);
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return generic_writepages(mapping, wbc);
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}
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/**
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* stuffed_readpage - Fill in a Linux page with stuffed file data
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* @ip: the inode
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* @page: the page
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*
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* Returns: errno
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*/
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static int stuffed_readpage(struct gfs2_inode *ip, struct page *page)
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{
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struct buffer_head *dibh;
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void *kaddr;
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int error;
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/*
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* Due to the order of unstuffing files and ->nopage(), we can be
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* asked for a zero page in the case of a stuffed file being extended,
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* so we need to supply one here. It doesn't happen often.
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*/
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if (unlikely(page->index)) {
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zero_user_page(page, 0, PAGE_CACHE_SIZE, KM_USER0);
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return 0;
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}
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error = gfs2_meta_inode_buffer(ip, &dibh);
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if (error)
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return error;
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kaddr = kmap_atomic(page, KM_USER0);
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memcpy(kaddr, dibh->b_data + sizeof(struct gfs2_dinode),
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ip->i_di.di_size);
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memset(kaddr + ip->i_di.di_size, 0, PAGE_CACHE_SIZE - ip->i_di.di_size);
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kunmap_atomic(kaddr, KM_USER0);
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flush_dcache_page(page);
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brelse(dibh);
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SetPageUptodate(page);
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return 0;
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}
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/**
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* gfs2_readpage - readpage with locking
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* @file: The file to read a page for. N.B. This may be NULL if we are
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* reading an internal file.
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* @page: The page to read
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*
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* Returns: errno
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*/
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static int gfs2_readpage(struct file *file, struct page *page)
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{
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struct gfs2_inode *ip = GFS2_I(page->mapping->host);
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struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host);
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struct gfs2_file *gf = NULL;
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struct gfs2_holder gh;
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int error;
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int do_unlock = 0;
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if (likely(file != &gfs2_internal_file_sentinel)) {
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if (file) {
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gf = file->private_data;
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if (test_bit(GFF_EXLOCK, &gf->f_flags))
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/* gfs2_sharewrite_nopage has grabbed the ip->i_gl already */
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goto skip_lock;
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}
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gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME|LM_FLAG_TRY_1CB, &gh);
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do_unlock = 1;
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error = gfs2_glock_nq_atime(&gh);
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if (unlikely(error))
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goto out_unlock;
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}
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skip_lock:
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if (gfs2_is_stuffed(ip)) {
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error = stuffed_readpage(ip, page);
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unlock_page(page);
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} else
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error = mpage_readpage(page, gfs2_get_block);
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if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
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error = -EIO;
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if (do_unlock) {
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gfs2_glock_dq_m(1, &gh);
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gfs2_holder_uninit(&gh);
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}
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out:
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return error;
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out_unlock:
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unlock_page(page);
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if (error == GLR_TRYFAILED) {
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error = AOP_TRUNCATED_PAGE;
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yield();
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}
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if (do_unlock)
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gfs2_holder_uninit(&gh);
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goto out;
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}
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/**
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* gfs2_readpages - Read a bunch of pages at once
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*
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* Some notes:
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* 1. This is only for readahead, so we can simply ignore any things
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* which are slightly inconvenient (such as locking conflicts between
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* the page lock and the glock) and return having done no I/O. Its
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* obviously not something we'd want to do on too regular a basis.
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* Any I/O we ignore at this time will be done via readpage later.
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* 2. We don't handle stuffed files here we let readpage do the honours.
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* 3. mpage_readpages() does most of the heavy lifting in the common case.
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* 4. gfs2_get_block() is relied upon to set BH_Boundary in the right places.
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* 5. We use LM_FLAG_TRY_1CB here, effectively we then have lock-ahead as
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* well as read-ahead.
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*/
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static int gfs2_readpages(struct file *file, struct address_space *mapping,
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struct list_head *pages, unsigned nr_pages)
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{
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struct inode *inode = mapping->host;
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struct gfs2_inode *ip = GFS2_I(inode);
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struct gfs2_sbd *sdp = GFS2_SB(inode);
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struct gfs2_holder gh;
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int ret = 0;
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int do_unlock = 0;
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if (likely(file != &gfs2_internal_file_sentinel)) {
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if (file) {
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struct gfs2_file *gf = file->private_data;
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if (test_bit(GFF_EXLOCK, &gf->f_flags))
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goto skip_lock;
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}
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gfs2_holder_init(ip->i_gl, LM_ST_SHARED,
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LM_FLAG_TRY_1CB|GL_ATIME, &gh);
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do_unlock = 1;
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ret = gfs2_glock_nq_atime(&gh);
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if (ret == GLR_TRYFAILED)
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goto out_noerror;
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if (unlikely(ret))
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goto out_unlock;
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}
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skip_lock:
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if (!gfs2_is_stuffed(ip))
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ret = mpage_readpages(mapping, pages, nr_pages, gfs2_get_block);
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if (do_unlock) {
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gfs2_glock_dq_m(1, &gh);
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gfs2_holder_uninit(&gh);
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}
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out:
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if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
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ret = -EIO;
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return ret;
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out_noerror:
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ret = 0;
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out_unlock:
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if (do_unlock)
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gfs2_holder_uninit(&gh);
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goto out;
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}
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/**
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* gfs2_prepare_write - Prepare to write a page to a file
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* @file: The file to write to
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* @page: The page which is to be prepared for writing
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* @from: From (byte range within page)
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* @to: To (byte range within page)
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*
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* Returns: errno
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*/
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static int gfs2_prepare_write(struct file *file, struct page *page,
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unsigned from, unsigned to)
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{
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struct gfs2_inode *ip = GFS2_I(page->mapping->host);
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struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host);
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unsigned int data_blocks, ind_blocks, rblocks;
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int alloc_required;
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int error = 0;
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loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + from;
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loff_t end = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
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struct gfs2_alloc *al;
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unsigned int write_len = to - from;
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gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_ATIME|LM_FLAG_TRY_1CB, &ip->i_gh);
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error = gfs2_glock_nq_atime(&ip->i_gh);
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if (unlikely(error)) {
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if (error == GLR_TRYFAILED) {
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unlock_page(page);
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error = AOP_TRUNCATED_PAGE;
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yield();
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}
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goto out_uninit;
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}
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gfs2_write_calc_reserv(ip, write_len, &data_blocks, &ind_blocks);
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error = gfs2_write_alloc_required(ip, pos, write_len, &alloc_required);
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if (error)
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goto out_unlock;
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ip->i_alloc.al_requested = 0;
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if (alloc_required) {
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al = gfs2_alloc_get(ip);
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error = gfs2_quota_lock(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
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if (error)
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goto out_alloc_put;
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error = gfs2_quota_check(ip, ip->i_inode.i_uid, ip->i_inode.i_gid);
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if (error)
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goto out_qunlock;
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al->al_requested = data_blocks + ind_blocks;
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error = gfs2_inplace_reserve(ip);
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if (error)
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goto out_qunlock;
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}
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rblocks = RES_DINODE + ind_blocks;
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if (gfs2_is_jdata(ip))
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rblocks += data_blocks ? data_blocks : 1;
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if (ind_blocks || data_blocks)
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rblocks += RES_STATFS + RES_QUOTA;
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error = gfs2_trans_begin(sdp, rblocks, 0);
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if (error)
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goto out;
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if (gfs2_is_stuffed(ip)) {
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if (end > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) {
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error = gfs2_unstuff_dinode(ip, page);
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if (error == 0)
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goto prepare_write;
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} else if (!PageUptodate(page))
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error = stuffed_readpage(ip, page);
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goto out;
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}
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prepare_write:
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error = block_prepare_write(page, from, to, gfs2_get_block);
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out:
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if (error) {
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gfs2_trans_end(sdp);
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if (alloc_required) {
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gfs2_inplace_release(ip);
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out_qunlock:
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gfs2_quota_unlock(ip);
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out_alloc_put:
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gfs2_alloc_put(ip);
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}
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out_unlock:
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gfs2_glock_dq_m(1, &ip->i_gh);
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out_uninit:
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gfs2_holder_uninit(&ip->i_gh);
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}
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return error;
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}
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/**
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* adjust_fs_space - Adjusts the free space available due to gfs2_grow
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* @inode: the rindex inode
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*/
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static void adjust_fs_space(struct inode *inode)
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{
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struct gfs2_sbd *sdp = inode->i_sb->s_fs_info;
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struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
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struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
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u64 fs_total, new_free;
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/* Total up the file system space, according to the latest rindex. */
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fs_total = gfs2_ri_total(sdp);
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spin_lock(&sdp->sd_statfs_spin);
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if (fs_total > (m_sc->sc_total + l_sc->sc_total))
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new_free = fs_total - (m_sc->sc_total + l_sc->sc_total);
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else
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new_free = 0;
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spin_unlock(&sdp->sd_statfs_spin);
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fs_warn(sdp, "File system extended by %llu blocks.\n",
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(unsigned long long)new_free);
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gfs2_statfs_change(sdp, new_free, new_free, 0);
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}
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/**
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* gfs2_commit_write - Commit write to a file
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* @file: The file to write to
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* @page: The page containing the data
|
|
* @from: From (byte range within page)
|
|
* @to: To (byte range within page)
|
|
*
|
|
* Returns: errno
|
|
*/
|
|
|
|
static int gfs2_commit_write(struct file *file, struct page *page,
|
|
unsigned from, unsigned to)
|
|
{
|
|
struct inode *inode = page->mapping->host;
|
|
struct gfs2_inode *ip = GFS2_I(inode);
|
|
struct gfs2_sbd *sdp = GFS2_SB(inode);
|
|
int error = -EOPNOTSUPP;
|
|
struct buffer_head *dibh;
|
|
struct gfs2_alloc *al = &ip->i_alloc;
|
|
struct gfs2_dinode *di;
|
|
|
|
if (gfs2_assert_withdraw(sdp, gfs2_glock_is_locked_by_me(ip->i_gl)))
|
|
goto fail_nounlock;
|
|
|
|
error = gfs2_meta_inode_buffer(ip, &dibh);
|
|
if (error)
|
|
goto fail_endtrans;
|
|
|
|
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
|
|
di = (struct gfs2_dinode *)dibh->b_data;
|
|
|
|
if (gfs2_is_stuffed(ip)) {
|
|
u64 file_size;
|
|
void *kaddr;
|
|
|
|
file_size = ((u64)page->index << PAGE_CACHE_SHIFT) + to;
|
|
|
|
kaddr = kmap_atomic(page, KM_USER0);
|
|
memcpy(dibh->b_data + sizeof(struct gfs2_dinode) + from,
|
|
kaddr + from, to - from);
|
|
kunmap_atomic(kaddr, KM_USER0);
|
|
|
|
SetPageUptodate(page);
|
|
|
|
if (inode->i_size < file_size) {
|
|
i_size_write(inode, file_size);
|
|
mark_inode_dirty(inode);
|
|
}
|
|
} else {
|
|
if (sdp->sd_args.ar_data == GFS2_DATA_ORDERED ||
|
|
gfs2_is_jdata(ip))
|
|
gfs2_page_add_databufs(ip, page, from, to);
|
|
error = generic_commit_write(file, page, from, to);
|
|
if (error)
|
|
goto fail;
|
|
}
|
|
|
|
if (ip->i_di.di_size < inode->i_size) {
|
|
ip->i_di.di_size = inode->i_size;
|
|
di->di_size = cpu_to_be64(inode->i_size);
|
|
}
|
|
|
|
if (inode == sdp->sd_rindex)
|
|
adjust_fs_space(inode);
|
|
|
|
brelse(dibh);
|
|
gfs2_trans_end(sdp);
|
|
if (al->al_requested) {
|
|
gfs2_inplace_release(ip);
|
|
gfs2_quota_unlock(ip);
|
|
gfs2_alloc_put(ip);
|
|
}
|
|
unlock_page(page);
|
|
gfs2_glock_dq_m(1, &ip->i_gh);
|
|
lock_page(page);
|
|
gfs2_holder_uninit(&ip->i_gh);
|
|
return 0;
|
|
|
|
fail:
|
|
brelse(dibh);
|
|
fail_endtrans:
|
|
gfs2_trans_end(sdp);
|
|
if (al->al_requested) {
|
|
gfs2_inplace_release(ip);
|
|
gfs2_quota_unlock(ip);
|
|
gfs2_alloc_put(ip);
|
|
}
|
|
unlock_page(page);
|
|
gfs2_glock_dq_m(1, &ip->i_gh);
|
|
lock_page(page);
|
|
gfs2_holder_uninit(&ip->i_gh);
|
|
fail_nounlock:
|
|
ClearPageUptodate(page);
|
|
return error;
|
|
}
|
|
|
|
/**
|
|
* gfs2_set_page_dirty - Page dirtying function
|
|
* @page: The page to dirty
|
|
*
|
|
* Returns: 1 if it dirtyed the page, or 0 otherwise
|
|
*/
|
|
|
|
static int gfs2_set_page_dirty(struct page *page)
|
|
{
|
|
struct gfs2_inode *ip = GFS2_I(page->mapping->host);
|
|
struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host);
|
|
|
|
if (sdp->sd_args.ar_data == GFS2_DATA_ORDERED || gfs2_is_jdata(ip))
|
|
SetPageChecked(page);
|
|
return __set_page_dirty_buffers(page);
|
|
}
|
|
|
|
/**
|
|
* gfs2_bmap - Block map function
|
|
* @mapping: Address space info
|
|
* @lblock: The block to map
|
|
*
|
|
* Returns: The disk address for the block or 0 on hole or error
|
|
*/
|
|
|
|
static sector_t gfs2_bmap(struct address_space *mapping, sector_t lblock)
|
|
{
|
|
struct gfs2_inode *ip = GFS2_I(mapping->host);
|
|
struct gfs2_holder i_gh;
|
|
sector_t dblock = 0;
|
|
int error;
|
|
|
|
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
|
|
if (error)
|
|
return 0;
|
|
|
|
if (!gfs2_is_stuffed(ip))
|
|
dblock = generic_block_bmap(mapping, lblock, gfs2_get_block);
|
|
|
|
gfs2_glock_dq_uninit(&i_gh);
|
|
|
|
return dblock;
|
|
}
|
|
|
|
static void discard_buffer(struct gfs2_sbd *sdp, struct buffer_head *bh)
|
|
{
|
|
struct gfs2_bufdata *bd;
|
|
|
|
gfs2_log_lock(sdp);
|
|
bd = bh->b_private;
|
|
if (bd) {
|
|
bd->bd_bh = NULL;
|
|
bh->b_private = NULL;
|
|
if (!bd->bd_ail && list_empty(&bd->bd_le.le_list))
|
|
kmem_cache_free(gfs2_bufdata_cachep, bd);
|
|
}
|
|
gfs2_log_unlock(sdp);
|
|
|
|
lock_buffer(bh);
|
|
clear_buffer_dirty(bh);
|
|
bh->b_bdev = NULL;
|
|
clear_buffer_mapped(bh);
|
|
clear_buffer_req(bh);
|
|
clear_buffer_new(bh);
|
|
clear_buffer_delay(bh);
|
|
unlock_buffer(bh);
|
|
}
|
|
|
|
static void gfs2_invalidatepage(struct page *page, unsigned long offset)
|
|
{
|
|
struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host);
|
|
struct buffer_head *head, *bh, *next;
|
|
unsigned int curr_off = 0;
|
|
|
|
BUG_ON(!PageLocked(page));
|
|
if (offset == 0)
|
|
ClearPageChecked(page);
|
|
if (!page_has_buffers(page))
|
|
return;
|
|
|
|
bh = head = page_buffers(page);
|
|
do {
|
|
unsigned int next_off = curr_off + bh->b_size;
|
|
next = bh->b_this_page;
|
|
|
|
if (offset <= curr_off)
|
|
discard_buffer(sdp, bh);
|
|
|
|
curr_off = next_off;
|
|
bh = next;
|
|
} while (bh != head);
|
|
|
|
if (!offset)
|
|
try_to_release_page(page, 0);
|
|
|
|
return;
|
|
}
|
|
|
|
/**
|
|
* gfs2_ok_for_dio - check that dio is valid on this file
|
|
* @ip: The inode
|
|
* @rw: READ or WRITE
|
|
* @offset: The offset at which we are reading or writing
|
|
*
|
|
* Returns: 0 (to ignore the i/o request and thus fall back to buffered i/o)
|
|
* 1 (to accept the i/o request)
|
|
*/
|
|
static int gfs2_ok_for_dio(struct gfs2_inode *ip, int rw, loff_t offset)
|
|
{
|
|
/*
|
|
* Should we return an error here? I can't see that O_DIRECT for
|
|
* a journaled file makes any sense. For now we'll silently fall
|
|
* back to buffered I/O, likewise we do the same for stuffed
|
|
* files since they are (a) small and (b) unaligned.
|
|
*/
|
|
if (gfs2_is_jdata(ip))
|
|
return 0;
|
|
|
|
if (gfs2_is_stuffed(ip))
|
|
return 0;
|
|
|
|
if (offset > i_size_read(&ip->i_inode))
|
|
return 0;
|
|
return 1;
|
|
}
|
|
|
|
|
|
|
|
static ssize_t gfs2_direct_IO(int rw, struct kiocb *iocb,
|
|
const struct iovec *iov, loff_t offset,
|
|
unsigned long nr_segs)
|
|
{
|
|
struct file *file = iocb->ki_filp;
|
|
struct inode *inode = file->f_mapping->host;
|
|
struct gfs2_inode *ip = GFS2_I(inode);
|
|
struct gfs2_holder gh;
|
|
int rv;
|
|
|
|
/*
|
|
* Deferred lock, even if its a write, since we do no allocation
|
|
* on this path. All we need change is atime, and this lock mode
|
|
* ensures that other nodes have flushed their buffered read caches
|
|
* (i.e. their page cache entries for this inode). We do not,
|
|
* unfortunately have the option of only flushing a range like
|
|
* the VFS does.
|
|
*/
|
|
gfs2_holder_init(ip->i_gl, LM_ST_DEFERRED, GL_ATIME, &gh);
|
|
rv = gfs2_glock_nq_atime(&gh);
|
|
if (rv)
|
|
return rv;
|
|
rv = gfs2_ok_for_dio(ip, rw, offset);
|
|
if (rv != 1)
|
|
goto out; /* dio not valid, fall back to buffered i/o */
|
|
|
|
rv = blockdev_direct_IO_no_locking(rw, iocb, inode, inode->i_sb->s_bdev,
|
|
iov, offset, nr_segs,
|
|
gfs2_get_block_direct, NULL);
|
|
out:
|
|
gfs2_glock_dq_m(1, &gh);
|
|
gfs2_holder_uninit(&gh);
|
|
return rv;
|
|
}
|
|
|
|
/**
|
|
* stuck_releasepage - We're stuck in gfs2_releasepage(). Print stuff out.
|
|
* @bh: the buffer we're stuck on
|
|
*
|
|
*/
|
|
|
|
static void stuck_releasepage(struct buffer_head *bh)
|
|
{
|
|
struct inode *inode = bh->b_page->mapping->host;
|
|
struct gfs2_sbd *sdp = inode->i_sb->s_fs_info;
|
|
struct gfs2_bufdata *bd = bh->b_private;
|
|
struct gfs2_glock *gl;
|
|
static unsigned limit = 0;
|
|
|
|
if (limit > 3)
|
|
return;
|
|
limit++;
|
|
|
|
fs_warn(sdp, "stuck in gfs2_releasepage() %p\n", inode);
|
|
fs_warn(sdp, "blkno = %llu, bh->b_count = %d\n",
|
|
(unsigned long long)bh->b_blocknr, atomic_read(&bh->b_count));
|
|
fs_warn(sdp, "pinned = %u\n", buffer_pinned(bh));
|
|
fs_warn(sdp, "bh->b_private = %s\n", (bd) ? "!NULL" : "NULL");
|
|
|
|
if (!bd)
|
|
return;
|
|
|
|
gl = bd->bd_gl;
|
|
|
|
fs_warn(sdp, "gl = (%u, %llu)\n",
|
|
gl->gl_name.ln_type, (unsigned long long)gl->gl_name.ln_number);
|
|
|
|
fs_warn(sdp, "bd_list_tr = %s, bd_le.le_list = %s\n",
|
|
(list_empty(&bd->bd_list_tr)) ? "no" : "yes",
|
|
(list_empty(&bd->bd_le.le_list)) ? "no" : "yes");
|
|
|
|
if (gl->gl_ops == &gfs2_inode_glops) {
|
|
struct gfs2_inode *ip = gl->gl_object;
|
|
unsigned int x;
|
|
|
|
if (!ip)
|
|
return;
|
|
|
|
fs_warn(sdp, "ip = %llu %llu\n",
|
|
(unsigned long long)ip->i_no_formal_ino,
|
|
(unsigned long long)ip->i_no_addr);
|
|
|
|
for (x = 0; x < GFS2_MAX_META_HEIGHT; x++)
|
|
fs_warn(sdp, "ip->i_cache[%u] = %s\n",
|
|
x, (ip->i_cache[x]) ? "!NULL" : "NULL");
|
|
}
|
|
}
|
|
|
|
/**
|
|
* gfs2_releasepage - free the metadata associated with a page
|
|
* @page: the page that's being released
|
|
* @gfp_mask: passed from Linux VFS, ignored by us
|
|
*
|
|
* Call try_to_free_buffers() if the buffers in this page can be
|
|
* released.
|
|
*
|
|
* Returns: 0
|
|
*/
|
|
|
|
int gfs2_releasepage(struct page *page, gfp_t gfp_mask)
|
|
{
|
|
struct inode *aspace = page->mapping->host;
|
|
struct gfs2_sbd *sdp = aspace->i_sb->s_fs_info;
|
|
struct buffer_head *bh, *head;
|
|
struct gfs2_bufdata *bd;
|
|
unsigned long t = jiffies + gfs2_tune_get(sdp, gt_stall_secs) * HZ;
|
|
|
|
if (!page_has_buffers(page))
|
|
goto out;
|
|
|
|
head = bh = page_buffers(page);
|
|
do {
|
|
while (atomic_read(&bh->b_count)) {
|
|
if (!atomic_read(&aspace->i_writecount))
|
|
return 0;
|
|
|
|
if (!(gfp_mask & __GFP_WAIT))
|
|
return 0;
|
|
|
|
if (time_after_eq(jiffies, t)) {
|
|
stuck_releasepage(bh);
|
|
/* should we withdraw here? */
|
|
return 0;
|
|
}
|
|
|
|
yield();
|
|
}
|
|
|
|
gfs2_assert_warn(sdp, !buffer_pinned(bh));
|
|
gfs2_assert_warn(sdp, !buffer_dirty(bh));
|
|
|
|
gfs2_log_lock(sdp);
|
|
bd = bh->b_private;
|
|
if (bd) {
|
|
gfs2_assert_warn(sdp, bd->bd_bh == bh);
|
|
gfs2_assert_warn(sdp, list_empty(&bd->bd_list_tr));
|
|
gfs2_assert_warn(sdp, !bd->bd_ail);
|
|
bd->bd_bh = NULL;
|
|
if (!list_empty(&bd->bd_le.le_list))
|
|
bd = NULL;
|
|
bh->b_private = NULL;
|
|
}
|
|
gfs2_log_unlock(sdp);
|
|
if (bd)
|
|
kmem_cache_free(gfs2_bufdata_cachep, bd);
|
|
|
|
bh = bh->b_this_page;
|
|
} while (bh != head);
|
|
|
|
out:
|
|
return try_to_free_buffers(page);
|
|
}
|
|
|
|
const struct address_space_operations gfs2_file_aops = {
|
|
.writepage = gfs2_writepage,
|
|
.writepages = gfs2_writepages,
|
|
.readpage = gfs2_readpage,
|
|
.readpages = gfs2_readpages,
|
|
.sync_page = block_sync_page,
|
|
.prepare_write = gfs2_prepare_write,
|
|
.commit_write = gfs2_commit_write,
|
|
.set_page_dirty = gfs2_set_page_dirty,
|
|
.bmap = gfs2_bmap,
|
|
.invalidatepage = gfs2_invalidatepage,
|
|
.releasepage = gfs2_releasepage,
|
|
.direct_IO = gfs2_direct_IO,
|
|
};
|
|
|