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	Before this patch, several functions in gfs2 related to the updating of the statfs file used a newly acquired/read buffer_head for the local statfs file. This is completely unnecessary, because other nodes should never update it. Recreating the buffer is a waste of time. This patch allows gfs2 to read in the local statefs buffer_head at mount time and keep it around until unmount time. Signed-off-by: Bob Peterson <rpeterso@redhat.com>
		
			
				
	
	
		
			811 lines
		
	
	
	
		
			20 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			811 lines
		
	
	
	
		
			20 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
// SPDX-License-Identifier: GPL-2.0-only
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/*
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 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
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 * Copyright (C) 2004-2008 Red Hat, Inc.  All rights reserved.
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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/swap.h>
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#include <linux/gfs2_ondisk.h>
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#include <linux/backing-dev.h>
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#include <linux/uio.h>
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#include <trace/events/writeback.h>
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#include <linux/sched/signal.h>
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 | 
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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 "quota.h"
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#include "trans.h"
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#include "rgrp.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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#include "aops.h"
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						|
 | 
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void gfs2_page_add_databufs(struct gfs2_inode *ip, struct page *page,
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						|
			    unsigned int from, unsigned int len)
 | 
						|
{
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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 to = from + len;
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						|
	unsigned int start, end;
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						|
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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)
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			continue;
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						|
		if (start >= to)
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			break;
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		set_buffer_uptodate(bh);
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		gfs2_trans_add_data(ip->i_gl, bh);
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	}
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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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						|
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	error = gfs2_block_map(inode, lblock, bh_result, 0);
 | 
						|
	if (error)
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		return error;
 | 
						|
	if (!buffer_mapped(bh_result))
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		return -ENODATA;
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						|
	return 0;
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						|
}
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						|
 | 
						|
/**
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						|
 * gfs2_writepage - Write page for writeback mappings
 | 
						|
 * @page: The page
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						|
 * @wbc: The writeback control
 | 
						|
 */
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						|
static int gfs2_writepage(struct page *page, struct writeback_control *wbc)
 | 
						|
{
 | 
						|
	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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						|
	struct iomap_writepage_ctx wpc = { };
 | 
						|
 | 
						|
	if (gfs2_assert_withdraw(sdp, gfs2_glock_is_held_excl(ip->i_gl)))
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						|
		goto out;
 | 
						|
	if (current->journal_info)
 | 
						|
		goto redirty;
 | 
						|
	return iomap_writepage(page, wbc, &wpc, &gfs2_writeback_ops);
 | 
						|
 | 
						|
redirty:
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						|
	redirty_page_for_writepage(wbc, page);
 | 
						|
out:
 | 
						|
	unlock_page(page);
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						|
	return 0;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * gfs2_write_jdata_page - gfs2 jdata-specific version of block_write_full_page
 | 
						|
 * @page: The page to write
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						|
 * @wbc: The writeback control
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						|
 *
 | 
						|
 * This is the same as calling block_write_full_page, but it also
 | 
						|
 * writes pages outside of i_size
 | 
						|
 */
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static int gfs2_write_jdata_page(struct page *page,
 | 
						|
				 struct writeback_control *wbc)
 | 
						|
{
 | 
						|
	struct inode * const inode = page->mapping->host;
 | 
						|
	loff_t i_size = i_size_read(inode);
 | 
						|
	const pgoff_t end_index = i_size >> PAGE_SHIFT;
 | 
						|
	unsigned offset;
 | 
						|
 | 
						|
	/*
 | 
						|
	 * The page straddles i_size.  It must be zeroed out on each and every
 | 
						|
	 * writepage invocation because it may be mmapped.  "A file is mapped
 | 
						|
	 * in multiples of the page size.  For a file that is not a multiple of
 | 
						|
	 * the  page size, the remaining memory is zeroed when mapped, and
 | 
						|
	 * writes to that region are not written out to the file."
 | 
						|
	 */
 | 
						|
	offset = i_size & (PAGE_SIZE - 1);
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						|
	if (page->index == end_index && offset)
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						|
		zero_user_segment(page, offset, PAGE_SIZE);
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						|
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						|
	return __block_write_full_page(inode, page, gfs2_get_block_noalloc, wbc,
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						|
				       end_buffer_async_write);
 | 
						|
}
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						|
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						|
/**
 | 
						|
 * __gfs2_jdata_writepage - The core of jdata writepage
 | 
						|
 * @page: The page to write
 | 
						|
 * @wbc: The writeback control
 | 
						|
 *
 | 
						|
 * This is shared between writepage and writepages and implements the
 | 
						|
 * core of the writepage operation. If a transaction is required then
 | 
						|
 * PageChecked will have been set and the transaction will have
 | 
						|
 * already been started before this is called.
 | 
						|
 */
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static int __gfs2_jdata_writepage(struct page *page, struct writeback_control *wbc)
 | 
						|
{
 | 
						|
	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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						|
 | 
						|
	if (PageChecked(page)) {
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						|
		ClearPageChecked(page);
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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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					     BIT(BH_Dirty)|BIT(BH_Uptodate));
 | 
						|
		}
 | 
						|
		gfs2_page_add_databufs(ip, page, 0, sdp->sd_vfs->s_blocksize);
 | 
						|
	}
 | 
						|
	return gfs2_write_jdata_page(page, wbc);
 | 
						|
}
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						|
/**
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						|
 * gfs2_jdata_writepage - Write complete page
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						|
 * @page: Page to write
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						|
 * @wbc: The writeback control
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 *
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 * Returns: errno
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						|
 *
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 */
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static int gfs2_jdata_writepage(struct page *page, struct writeback_control *wbc)
 | 
						|
{
 | 
						|
	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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						|
	if (gfs2_assert_withdraw(sdp, gfs2_glock_is_held_excl(ip->i_gl)))
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						|
		goto out;
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						|
	if (PageChecked(page) || current->journal_info)
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		goto out_ignore;
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	return __gfs2_jdata_writepage(page, wbc);
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out_ignore:
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	redirty_page_for_writepage(wbc, page);
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out:
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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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 * Used for both ordered and writeback modes.
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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 gfs2_sbd *sdp = gfs2_mapping2sbd(mapping);
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	struct iomap_writepage_ctx wpc = { };
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	int ret;
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	/*
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	 * Even if we didn't write any pages here, we might still be holding
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	 * dirty pages in the ail. We forcibly flush the ail because we don't
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	 * want balance_dirty_pages() to loop indefinitely trying to write out
 | 
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	 * pages held in the ail that it can't find.
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	 */
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	ret = iomap_writepages(mapping, wbc, &wpc, &gfs2_writeback_ops);
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	if (ret == 0)
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		set_bit(SDF_FORCE_AIL_FLUSH, &sdp->sd_flags);
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	return ret;
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}
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/**
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 * gfs2_write_jdata_pagevec - Write back a pagevec's worth of pages
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 * @mapping: The mapping
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 * @wbc: The writeback control
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 * @pvec: The vector of pages
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 * @nr_pages: The number of pages to write
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 * @done_index: Page index
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 *
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 * Returns: non-zero if loop should terminate, zero otherwise
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 */
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static int gfs2_write_jdata_pagevec(struct address_space *mapping,
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				    struct writeback_control *wbc,
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				    struct pagevec *pvec,
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				    int nr_pages,
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				    pgoff_t *done_index)
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{
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	struct inode *inode = mapping->host;
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	struct gfs2_sbd *sdp = GFS2_SB(inode);
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	unsigned nrblocks = nr_pages * (PAGE_SIZE >> inode->i_blkbits);
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	int i;
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	int ret;
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	ret = gfs2_trans_begin(sdp, nrblocks, nrblocks);
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						|
	if (ret < 0)
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		return ret;
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	for(i = 0; i < nr_pages; i++) {
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		struct page *page = pvec->pages[i];
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		*done_index = page->index;
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		lock_page(page);
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		if (unlikely(page->mapping != mapping)) {
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continue_unlock:
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			unlock_page(page);
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			continue;
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		}
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		if (!PageDirty(page)) {
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			/* someone wrote it for us */
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			goto continue_unlock;
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						|
		}
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						|
		if (PageWriteback(page)) {
 | 
						|
			if (wbc->sync_mode != WB_SYNC_NONE)
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				wait_on_page_writeback(page);
 | 
						|
			else
 | 
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				goto continue_unlock;
 | 
						|
		}
 | 
						|
 | 
						|
		BUG_ON(PageWriteback(page));
 | 
						|
		if (!clear_page_dirty_for_io(page))
 | 
						|
			goto continue_unlock;
 | 
						|
 | 
						|
		trace_wbc_writepage(wbc, inode_to_bdi(inode));
 | 
						|
 | 
						|
		ret = __gfs2_jdata_writepage(page, wbc);
 | 
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		if (unlikely(ret)) {
 | 
						|
			if (ret == AOP_WRITEPAGE_ACTIVATE) {
 | 
						|
				unlock_page(page);
 | 
						|
				ret = 0;
 | 
						|
			} else {
 | 
						|
 | 
						|
				/*
 | 
						|
				 * done_index is set past this page,
 | 
						|
				 * so media errors will not choke
 | 
						|
				 * background writeout for the entire
 | 
						|
				 * file. This has consequences for
 | 
						|
				 * range_cyclic semantics (ie. it may
 | 
						|
				 * not be suitable for data integrity
 | 
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				 * writeout).
 | 
						|
				 */
 | 
						|
				*done_index = page->index + 1;
 | 
						|
				ret = 1;
 | 
						|
				break;
 | 
						|
			}
 | 
						|
		}
 | 
						|
 | 
						|
		/*
 | 
						|
		 * We stop writing back only if we are not doing
 | 
						|
		 * integrity sync. In case of integrity sync we have to
 | 
						|
		 * keep going until we have written all the pages
 | 
						|
		 * we tagged for writeback prior to entering this loop.
 | 
						|
		 */
 | 
						|
		if (--wbc->nr_to_write <= 0 && wbc->sync_mode == WB_SYNC_NONE) {
 | 
						|
			ret = 1;
 | 
						|
			break;
 | 
						|
		}
 | 
						|
 | 
						|
	}
 | 
						|
	gfs2_trans_end(sdp);
 | 
						|
	return ret;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * gfs2_write_cache_jdata - Like write_cache_pages but different
 | 
						|
 * @mapping: The mapping to write
 | 
						|
 * @wbc: The writeback control
 | 
						|
 *
 | 
						|
 * The reason that we use our own function here is that we need to
 | 
						|
 * start transactions before we grab page locks. This allows us
 | 
						|
 * to get the ordering right.
 | 
						|
 */
 | 
						|
 | 
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static int gfs2_write_cache_jdata(struct address_space *mapping,
 | 
						|
				  struct writeback_control *wbc)
 | 
						|
{
 | 
						|
	int ret = 0;
 | 
						|
	int done = 0;
 | 
						|
	struct pagevec pvec;
 | 
						|
	int nr_pages;
 | 
						|
	pgoff_t writeback_index;
 | 
						|
	pgoff_t index;
 | 
						|
	pgoff_t end;
 | 
						|
	pgoff_t done_index;
 | 
						|
	int cycled;
 | 
						|
	int range_whole = 0;
 | 
						|
	xa_mark_t tag;
 | 
						|
 | 
						|
	pagevec_init(&pvec);
 | 
						|
	if (wbc->range_cyclic) {
 | 
						|
		writeback_index = mapping->writeback_index; /* prev offset */
 | 
						|
		index = writeback_index;
 | 
						|
		if (index == 0)
 | 
						|
			cycled = 1;
 | 
						|
		else
 | 
						|
			cycled = 0;
 | 
						|
		end = -1;
 | 
						|
	} else {
 | 
						|
		index = wbc->range_start >> PAGE_SHIFT;
 | 
						|
		end = wbc->range_end >> PAGE_SHIFT;
 | 
						|
		if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
 | 
						|
			range_whole = 1;
 | 
						|
		cycled = 1; /* ignore range_cyclic tests */
 | 
						|
	}
 | 
						|
	if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
 | 
						|
		tag = PAGECACHE_TAG_TOWRITE;
 | 
						|
	else
 | 
						|
		tag = PAGECACHE_TAG_DIRTY;
 | 
						|
 | 
						|
retry:
 | 
						|
	if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
 | 
						|
		tag_pages_for_writeback(mapping, index, end);
 | 
						|
	done_index = index;
 | 
						|
	while (!done && (index <= end)) {
 | 
						|
		nr_pages = pagevec_lookup_range_tag(&pvec, mapping, &index, end,
 | 
						|
				tag);
 | 
						|
		if (nr_pages == 0)
 | 
						|
			break;
 | 
						|
 | 
						|
		ret = gfs2_write_jdata_pagevec(mapping, wbc, &pvec, nr_pages, &done_index);
 | 
						|
		if (ret)
 | 
						|
			done = 1;
 | 
						|
		if (ret > 0)
 | 
						|
			ret = 0;
 | 
						|
		pagevec_release(&pvec);
 | 
						|
		cond_resched();
 | 
						|
	}
 | 
						|
 | 
						|
	if (!cycled && !done) {
 | 
						|
		/*
 | 
						|
		 * range_cyclic:
 | 
						|
		 * We hit the last page and there is more work to be done: wrap
 | 
						|
		 * back to the start of the file
 | 
						|
		 */
 | 
						|
		cycled = 1;
 | 
						|
		index = 0;
 | 
						|
		end = writeback_index - 1;
 | 
						|
		goto retry;
 | 
						|
	}
 | 
						|
 | 
						|
	if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
 | 
						|
		mapping->writeback_index = done_index;
 | 
						|
 | 
						|
	return ret;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/**
 | 
						|
 * gfs2_jdata_writepages - Write a bunch of dirty pages back to disk
 | 
						|
 * @mapping: The mapping to write
 | 
						|
 * @wbc: The writeback control
 | 
						|
 * 
 | 
						|
 */
 | 
						|
 | 
						|
static int gfs2_jdata_writepages(struct address_space *mapping,
 | 
						|
				 struct writeback_control *wbc)
 | 
						|
{
 | 
						|
	struct gfs2_inode *ip = GFS2_I(mapping->host);
 | 
						|
	struct gfs2_sbd *sdp = GFS2_SB(mapping->host);
 | 
						|
	int ret;
 | 
						|
 | 
						|
	ret = gfs2_write_cache_jdata(mapping, wbc);
 | 
						|
	if (ret == 0 && wbc->sync_mode == WB_SYNC_ALL) {
 | 
						|
		gfs2_log_flush(sdp, ip->i_gl, GFS2_LOG_HEAD_FLUSH_NORMAL |
 | 
						|
			       GFS2_LFC_JDATA_WPAGES);
 | 
						|
		ret = gfs2_write_cache_jdata(mapping, wbc);
 | 
						|
	}
 | 
						|
	return ret;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * stuffed_readpage - Fill in a Linux page with stuffed file data
 | 
						|
 * @ip: the inode
 | 
						|
 * @page: the page
 | 
						|
 *
 | 
						|
 * Returns: errno
 | 
						|
 */
 | 
						|
static int stuffed_readpage(struct gfs2_inode *ip, struct page *page)
 | 
						|
{
 | 
						|
	struct buffer_head *dibh;
 | 
						|
	u64 dsize = i_size_read(&ip->i_inode);
 | 
						|
	void *kaddr;
 | 
						|
	int error;
 | 
						|
 | 
						|
	/*
 | 
						|
	 * Due to the order of unstuffing files and ->fault(), we can be
 | 
						|
	 * asked for a zero page in the case of a stuffed file being extended,
 | 
						|
	 * so we need to supply one here. It doesn't happen often.
 | 
						|
	 */
 | 
						|
	if (unlikely(page->index)) {
 | 
						|
		zero_user(page, 0, PAGE_SIZE);
 | 
						|
		SetPageUptodate(page);
 | 
						|
		return 0;
 | 
						|
	}
 | 
						|
 | 
						|
	error = gfs2_meta_inode_buffer(ip, &dibh);
 | 
						|
	if (error)
 | 
						|
		return error;
 | 
						|
 | 
						|
	kaddr = kmap_atomic(page);
 | 
						|
	if (dsize > gfs2_max_stuffed_size(ip))
 | 
						|
		dsize = gfs2_max_stuffed_size(ip);
 | 
						|
	memcpy(kaddr, dibh->b_data + sizeof(struct gfs2_dinode), dsize);
 | 
						|
	memset(kaddr + dsize, 0, PAGE_SIZE - dsize);
 | 
						|
	kunmap_atomic(kaddr);
 | 
						|
	flush_dcache_page(page);
 | 
						|
	brelse(dibh);
 | 
						|
	SetPageUptodate(page);
 | 
						|
 | 
						|
	return 0;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static int __gfs2_readpage(void *file, struct page *page)
 | 
						|
{
 | 
						|
	struct inode *inode = page->mapping->host;
 | 
						|
	struct gfs2_inode *ip = GFS2_I(inode);
 | 
						|
	struct gfs2_sbd *sdp = GFS2_SB(inode);
 | 
						|
	int error;
 | 
						|
 | 
						|
	if (!gfs2_is_jdata(ip) ||
 | 
						|
	    (i_blocksize(inode) == PAGE_SIZE && !page_has_buffers(page))) {
 | 
						|
		error = iomap_readpage(page, &gfs2_iomap_ops);
 | 
						|
	} else if (gfs2_is_stuffed(ip)) {
 | 
						|
		error = stuffed_readpage(ip, page);
 | 
						|
		unlock_page(page);
 | 
						|
	} else {
 | 
						|
		error = mpage_readpage(page, gfs2_block_map);
 | 
						|
	}
 | 
						|
 | 
						|
	if (unlikely(gfs2_withdrawn(sdp)))
 | 
						|
		return -EIO;
 | 
						|
 | 
						|
	return error;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * gfs2_readpage - read a page of a file
 | 
						|
 * @file: The file to read
 | 
						|
 * @page: The page of the file
 | 
						|
 */
 | 
						|
 | 
						|
static int gfs2_readpage(struct file *file, struct page *page)
 | 
						|
{
 | 
						|
	return __gfs2_readpage(file, page);
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * gfs2_internal_read - read an internal file
 | 
						|
 * @ip: The gfs2 inode
 | 
						|
 * @buf: The buffer to fill
 | 
						|
 * @pos: The file position
 | 
						|
 * @size: The amount to read
 | 
						|
 *
 | 
						|
 */
 | 
						|
 | 
						|
int gfs2_internal_read(struct gfs2_inode *ip, char *buf, loff_t *pos,
 | 
						|
                       unsigned size)
 | 
						|
{
 | 
						|
	struct address_space *mapping = ip->i_inode.i_mapping;
 | 
						|
	unsigned long index = *pos >> PAGE_SHIFT;
 | 
						|
	unsigned offset = *pos & (PAGE_SIZE - 1);
 | 
						|
	unsigned copied = 0;
 | 
						|
	unsigned amt;
 | 
						|
	struct page *page;
 | 
						|
	void *p;
 | 
						|
 | 
						|
	do {
 | 
						|
		amt = size - copied;
 | 
						|
		if (offset + size > PAGE_SIZE)
 | 
						|
			amt = PAGE_SIZE - offset;
 | 
						|
		page = read_cache_page(mapping, index, __gfs2_readpage, NULL);
 | 
						|
		if (IS_ERR(page))
 | 
						|
			return PTR_ERR(page);
 | 
						|
		p = kmap_atomic(page);
 | 
						|
		memcpy(buf + copied, p + offset, amt);
 | 
						|
		kunmap_atomic(p);
 | 
						|
		put_page(page);
 | 
						|
		copied += amt;
 | 
						|
		index++;
 | 
						|
		offset = 0;
 | 
						|
	} while(copied < size);
 | 
						|
	(*pos) += size;
 | 
						|
	return size;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * gfs2_readahead - Read a bunch of pages at once
 | 
						|
 * @rac: Read-ahead control structure
 | 
						|
 *
 | 
						|
 * Some notes:
 | 
						|
 * 1. This is only for readahead, so we can simply ignore any things
 | 
						|
 *    which are slightly inconvenient (such as locking conflicts between
 | 
						|
 *    the page lock and the glock) and return having done no I/O. Its
 | 
						|
 *    obviously not something we'd want to do on too regular a basis.
 | 
						|
 *    Any I/O we ignore at this time will be done via readpage later.
 | 
						|
 * 2. We don't handle stuffed files here we let readpage do the honours.
 | 
						|
 * 3. mpage_readahead() does most of the heavy lifting in the common case.
 | 
						|
 * 4. gfs2_block_map() is relied upon to set BH_Boundary in the right places.
 | 
						|
 */
 | 
						|
 | 
						|
static void gfs2_readahead(struct readahead_control *rac)
 | 
						|
{
 | 
						|
	struct inode *inode = rac->mapping->host;
 | 
						|
	struct gfs2_inode *ip = GFS2_I(inode);
 | 
						|
 | 
						|
	if (gfs2_is_stuffed(ip))
 | 
						|
		;
 | 
						|
	else if (gfs2_is_jdata(ip))
 | 
						|
		mpage_readahead(rac, gfs2_block_map);
 | 
						|
	else
 | 
						|
		iomap_readahead(rac, &gfs2_iomap_ops);
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * adjust_fs_space - Adjusts the free space available due to gfs2_grow
 | 
						|
 * @inode: the rindex inode
 | 
						|
 */
 | 
						|
void adjust_fs_space(struct inode *inode)
 | 
						|
{
 | 
						|
	struct gfs2_sbd *sdp = GFS2_SB(inode);
 | 
						|
	struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 | 
						|
	struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 | 
						|
	struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 | 
						|
	struct buffer_head *m_bh;
 | 
						|
	u64 fs_total, new_free;
 | 
						|
 | 
						|
	if (gfs2_trans_begin(sdp, 2 * RES_STATFS, 0) != 0)
 | 
						|
		return;
 | 
						|
 | 
						|
	/* Total up the file system space, according to the latest rindex. */
 | 
						|
	fs_total = gfs2_ri_total(sdp);
 | 
						|
	if (gfs2_meta_inode_buffer(m_ip, &m_bh) != 0)
 | 
						|
		goto out;
 | 
						|
 | 
						|
	spin_lock(&sdp->sd_statfs_spin);
 | 
						|
	gfs2_statfs_change_in(m_sc, m_bh->b_data +
 | 
						|
			      sizeof(struct gfs2_dinode));
 | 
						|
	if (fs_total > (m_sc->sc_total + l_sc->sc_total))
 | 
						|
		new_free = fs_total - (m_sc->sc_total + l_sc->sc_total);
 | 
						|
	else
 | 
						|
		new_free = 0;
 | 
						|
	spin_unlock(&sdp->sd_statfs_spin);
 | 
						|
	fs_warn(sdp, "File system extended by %llu blocks.\n",
 | 
						|
		(unsigned long long)new_free);
 | 
						|
	gfs2_statfs_change(sdp, new_free, new_free, 0);
 | 
						|
 | 
						|
	update_statfs(sdp, m_bh);
 | 
						|
	brelse(m_bh);
 | 
						|
out:
 | 
						|
	sdp->sd_rindex_uptodate = 0;
 | 
						|
	gfs2_trans_end(sdp);
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * jdata_set_page_dirty - Page dirtying function
 | 
						|
 * @page: The page to dirty
 | 
						|
 *
 | 
						|
 * Returns: 1 if it dirtyed the page, or 0 otherwise
 | 
						|
 */
 | 
						|
 
 | 
						|
static int jdata_set_page_dirty(struct page *page)
 | 
						|
{
 | 
						|
	if (current->journal_info)
 | 
						|
		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 = iomap_bmap(mapping, lblock, &gfs2_iomap_ops);
 | 
						|
 | 
						|
	gfs2_glock_dq_uninit(&i_gh);
 | 
						|
 | 
						|
	return dblock;
 | 
						|
}
 | 
						|
 | 
						|
static void gfs2_discard(struct gfs2_sbd *sdp, struct buffer_head *bh)
 | 
						|
{
 | 
						|
	struct gfs2_bufdata *bd;
 | 
						|
 | 
						|
	lock_buffer(bh);
 | 
						|
	gfs2_log_lock(sdp);
 | 
						|
	clear_buffer_dirty(bh);
 | 
						|
	bd = bh->b_private;
 | 
						|
	if (bd) {
 | 
						|
		if (!list_empty(&bd->bd_list) && !buffer_pinned(bh))
 | 
						|
			list_del_init(&bd->bd_list);
 | 
						|
		else {
 | 
						|
			spin_lock(&sdp->sd_ail_lock);
 | 
						|
			gfs2_remove_from_journal(bh, REMOVE_JDATA);
 | 
						|
			spin_unlock(&sdp->sd_ail_lock);
 | 
						|
		}
 | 
						|
	}
 | 
						|
	bh->b_bdev = NULL;
 | 
						|
	clear_buffer_mapped(bh);
 | 
						|
	clear_buffer_req(bh);
 | 
						|
	clear_buffer_new(bh);
 | 
						|
	gfs2_log_unlock(sdp);
 | 
						|
	unlock_buffer(bh);
 | 
						|
}
 | 
						|
 | 
						|
static void gfs2_invalidatepage(struct page *page, unsigned int offset,
 | 
						|
				unsigned int length)
 | 
						|
{
 | 
						|
	struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host);
 | 
						|
	unsigned int stop = offset + length;
 | 
						|
	int partial_page = (offset || length < PAGE_SIZE);
 | 
						|
	struct buffer_head *bh, *head;
 | 
						|
	unsigned long pos = 0;
 | 
						|
 | 
						|
	BUG_ON(!PageLocked(page));
 | 
						|
	if (!partial_page)
 | 
						|
		ClearPageChecked(page);
 | 
						|
	if (!page_has_buffers(page))
 | 
						|
		goto out;
 | 
						|
 | 
						|
	bh = head = page_buffers(page);
 | 
						|
	do {
 | 
						|
		if (pos + bh->b_size > stop)
 | 
						|
			return;
 | 
						|
 | 
						|
		if (offset <= pos)
 | 
						|
			gfs2_discard(sdp, bh);
 | 
						|
		pos += bh->b_size;
 | 
						|
		bh = bh->b_this_page;
 | 
						|
	} while (bh != head);
 | 
						|
out:
 | 
						|
	if (!partial_page)
 | 
						|
		try_to_release_page(page, 0);
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * 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
 | 
						|
 *
 | 
						|
 * Calls try_to_free_buffers() to free the buffers and put the page if the
 | 
						|
 * buffers can be released.
 | 
						|
 *
 | 
						|
 * Returns: 1 if the page was put or else 0
 | 
						|
 */
 | 
						|
 | 
						|
int gfs2_releasepage(struct page *page, gfp_t gfp_mask)
 | 
						|
{
 | 
						|
	struct address_space *mapping = page->mapping;
 | 
						|
	struct gfs2_sbd *sdp = gfs2_mapping2sbd(mapping);
 | 
						|
	struct buffer_head *bh, *head;
 | 
						|
	struct gfs2_bufdata *bd;
 | 
						|
 | 
						|
	if (!page_has_buffers(page))
 | 
						|
		return 0;
 | 
						|
 | 
						|
	/*
 | 
						|
	 * From xfs_vm_releasepage: mm accommodates an old ext3 case where
 | 
						|
	 * clean pages might not have had the dirty bit cleared.  Thus, it can
 | 
						|
	 * send actual dirty pages to ->releasepage() via shrink_active_list().
 | 
						|
	 *
 | 
						|
	 * As a workaround, we skip pages that contain dirty buffers below.
 | 
						|
	 * Once ->releasepage isn't called on dirty pages anymore, we can warn
 | 
						|
	 * on dirty buffers like we used to here again.
 | 
						|
	 */
 | 
						|
 | 
						|
	gfs2_log_lock(sdp);
 | 
						|
	head = bh = page_buffers(page);
 | 
						|
	do {
 | 
						|
		if (atomic_read(&bh->b_count))
 | 
						|
			goto cannot_release;
 | 
						|
		bd = bh->b_private;
 | 
						|
		if (bd && bd->bd_tr)
 | 
						|
			goto cannot_release;
 | 
						|
		if (buffer_dirty(bh) || WARN_ON(buffer_pinned(bh)))
 | 
						|
			goto cannot_release;
 | 
						|
		bh = bh->b_this_page;
 | 
						|
	} while(bh != head);
 | 
						|
 | 
						|
	head = bh = page_buffers(page);
 | 
						|
	do {
 | 
						|
		bd = bh->b_private;
 | 
						|
		if (bd) {
 | 
						|
			gfs2_assert_warn(sdp, bd->bd_bh == bh);
 | 
						|
			bd->bd_bh = NULL;
 | 
						|
			bh->b_private = NULL;
 | 
						|
			/*
 | 
						|
			 * The bd may still be queued as a revoke, in which
 | 
						|
			 * case we must not dequeue nor free it.
 | 
						|
			 */
 | 
						|
			if (!bd->bd_blkno && !list_empty(&bd->bd_list))
 | 
						|
				list_del_init(&bd->bd_list);
 | 
						|
			if (list_empty(&bd->bd_list))
 | 
						|
				kmem_cache_free(gfs2_bufdata_cachep, bd);
 | 
						|
		}
 | 
						|
 | 
						|
		bh = bh->b_this_page;
 | 
						|
	} while (bh != head);
 | 
						|
	gfs2_log_unlock(sdp);
 | 
						|
 | 
						|
	return try_to_free_buffers(page);
 | 
						|
 | 
						|
cannot_release:
 | 
						|
	gfs2_log_unlock(sdp);
 | 
						|
	return 0;
 | 
						|
}
 | 
						|
 | 
						|
static const struct address_space_operations gfs2_aops = {
 | 
						|
	.writepage = gfs2_writepage,
 | 
						|
	.writepages = gfs2_writepages,
 | 
						|
	.readpage = gfs2_readpage,
 | 
						|
	.readahead = gfs2_readahead,
 | 
						|
	.set_page_dirty = __set_page_dirty_nobuffers,
 | 
						|
	.releasepage = iomap_releasepage,
 | 
						|
	.invalidatepage = iomap_invalidatepage,
 | 
						|
	.bmap = gfs2_bmap,
 | 
						|
	.direct_IO = noop_direct_IO,
 | 
						|
	.migratepage = iomap_migrate_page,
 | 
						|
	.is_partially_uptodate = iomap_is_partially_uptodate,
 | 
						|
	.error_remove_page = generic_error_remove_page,
 | 
						|
};
 | 
						|
 | 
						|
static const struct address_space_operations gfs2_jdata_aops = {
 | 
						|
	.writepage = gfs2_jdata_writepage,
 | 
						|
	.writepages = gfs2_jdata_writepages,
 | 
						|
	.readpage = gfs2_readpage,
 | 
						|
	.readahead = gfs2_readahead,
 | 
						|
	.set_page_dirty = jdata_set_page_dirty,
 | 
						|
	.bmap = gfs2_bmap,
 | 
						|
	.invalidatepage = gfs2_invalidatepage,
 | 
						|
	.releasepage = gfs2_releasepage,
 | 
						|
	.is_partially_uptodate = block_is_partially_uptodate,
 | 
						|
	.error_remove_page = generic_error_remove_page,
 | 
						|
};
 | 
						|
 | 
						|
void gfs2_set_aops(struct inode *inode)
 | 
						|
{
 | 
						|
	if (gfs2_is_jdata(GFS2_I(inode)))
 | 
						|
		inode->i_mapping->a_ops = &gfs2_jdata_aops;
 | 
						|
	else
 | 
						|
		inode->i_mapping->a_ops = &gfs2_aops;
 | 
						|
}
 |