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811 lines
20 KiB
811 lines
20 KiB
// SPDX-License-Identifier: GPL-2.0-only |
|
/* |
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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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|
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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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{ |
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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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/** |
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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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|
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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); |
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if (error) |
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return error; |
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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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/** |
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* gfs2_writepage - Write page for writeback mappings |
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* @page: The page |
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* @wbc: The writeback control |
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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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struct iomap_writepage_ctx wpc = { }; |
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|
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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 (current->journal_info) |
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goto redirty; |
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return iomap_writepage(page, wbc, &wpc, &gfs2_writeback_ops); |
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|
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redirty: |
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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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/** |
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* gfs2_write_jdata_page - gfs2 jdata-specific version of block_write_full_page |
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* @page: The page to write |
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* @wbc: The writeback control |
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* |
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* This is the same as calling block_write_full_page, but it also |
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* writes pages outside of i_size |
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*/ |
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static int gfs2_write_jdata_page(struct page *page, |
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struct writeback_control *wbc) |
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{ |
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struct inode * const inode = page->mapping->host; |
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loff_t i_size = i_size_read(inode); |
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const pgoff_t end_index = i_size >> PAGE_SHIFT; |
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unsigned offset; |
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|
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/* |
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* The page straddles i_size. It must be zeroed out on each and every |
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* writepage invocation because it may be mmapped. "A file is mapped |
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* in multiples of the page size. For a file that is not a multiple of |
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* the page size, the remaining memory is zeroed when mapped, and |
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* writes to that region are not written out to the file." |
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*/ |
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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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|
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/** |
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* __gfs2_jdata_writepage - The core of jdata writepage |
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* @page: The page to write |
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* @wbc: The writeback control |
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* |
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* This is shared between writepage and writepages and implements the |
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* core of the writepage operation. If a transaction is required then |
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* PageChecked will have been set and the transaction will have |
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* already been started before this is called. |
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*/ |
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|
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static int __gfs2_jdata_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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|
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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)); |
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} |
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gfs2_page_add_databufs(ip, page, 0, sdp->sd_vfs->s_blocksize); |
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} |
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return gfs2_write_jdata_page(page, wbc); |
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} |
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|
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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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|
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static int gfs2_jdata_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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|
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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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/** |
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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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/* |
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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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/** |
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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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|
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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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|
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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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|
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if (PageWriteback(page)) { |
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if (wbc->sync_mode != WB_SYNC_NONE) |
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wait_on_page_writeback(page); |
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else |
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goto continue_unlock; |
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} |
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|
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BUG_ON(PageWriteback(page)); |
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if (!clear_page_dirty_for_io(page)) |
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goto continue_unlock; |
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|
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trace_wbc_writepage(wbc, inode_to_bdi(inode)); |
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|
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ret = __gfs2_jdata_writepage(page, wbc); |
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if (unlikely(ret)) { |
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if (ret == AOP_WRITEPAGE_ACTIVATE) { |
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unlock_page(page); |
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ret = 0; |
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} else { |
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|
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/* |
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* done_index is set past this page, |
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* so media errors will not choke |
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* background writeout for the entire |
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* file. This has consequences for |
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* range_cyclic semantics (ie. it may |
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* not be suitable for data integrity |
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* writeout). |
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*/ |
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*done_index = page->index + 1; |
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ret = 1; |
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break; |
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} |
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} |
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|
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/* |
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* We stop writing back only if we are not doing |
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* integrity sync. In case of integrity sync we have to |
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* keep going until we have written all the pages |
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* we tagged for writeback prior to entering this loop. |
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*/ |
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if (--wbc->nr_to_write <= 0 && wbc->sync_mode == WB_SYNC_NONE) { |
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ret = 1; |
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break; |
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} |
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|
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} |
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gfs2_trans_end(sdp); |
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return ret; |
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} |
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/** |
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* gfs2_write_cache_jdata - Like write_cache_pages but different |
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* @mapping: The mapping to write |
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* @wbc: The writeback control |
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* |
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* The reason that we use our own function here is that we need to |
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* start transactions before we grab page locks. This allows us |
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* to get the ordering right. |
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*/ |
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|
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static int gfs2_write_cache_jdata(struct address_space *mapping, |
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struct writeback_control *wbc) |
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{ |
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int ret = 0; |
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int done = 0; |
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struct pagevec pvec; |
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int nr_pages; |
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pgoff_t writeback_index; |
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pgoff_t index; |
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pgoff_t end; |
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pgoff_t done_index; |
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int cycled; |
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int range_whole = 0; |
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xa_mark_t tag; |
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|
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pagevec_init(&pvec); |
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if (wbc->range_cyclic) { |
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writeback_index = mapping->writeback_index; /* prev offset */ |
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index = writeback_index; |
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if (index == 0) |
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cycled = 1; |
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else |
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cycled = 0; |
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end = -1; |
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} else { |
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index = wbc->range_start >> PAGE_SHIFT; |
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end = wbc->range_end >> PAGE_SHIFT; |
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if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) |
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range_whole = 1; |
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cycled = 1; /* ignore range_cyclic tests */ |
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} |
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if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages) |
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tag = PAGECACHE_TAG_TOWRITE; |
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else |
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tag = PAGECACHE_TAG_DIRTY; |
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|
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retry: |
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if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages) |
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tag_pages_for_writeback(mapping, index, end); |
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done_index = index; |
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while (!done && (index <= end)) { |
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nr_pages = pagevec_lookup_range_tag(&pvec, mapping, &index, end, |
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tag); |
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if (nr_pages == 0) |
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break; |
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|
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ret = gfs2_write_jdata_pagevec(mapping, wbc, &pvec, nr_pages, &done_index); |
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if (ret) |
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done = 1; |
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if (ret > 0) |
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ret = 0; |
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pagevec_release(&pvec); |
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cond_resched(); |
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} |
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|
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if (!cycled && !done) { |
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/* |
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* range_cyclic: |
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* We hit the last page and there is more work to be done: wrap |
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* back to the start of the file |
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*/ |
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cycled = 1; |
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index = 0; |
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end = writeback_index - 1; |
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goto retry; |
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} |
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|
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if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0)) |
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mapping->writeback_index = done_index; |
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|
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return ret; |
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} |
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|
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/** |
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* gfs2_jdata_writepages - Write a bunch of dirty pages back to disk |
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* @mapping: The mapping to write |
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* @wbc: The writeback control |
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* |
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*/ |
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|
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static int gfs2_jdata_writepages(struct address_space *mapping, |
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struct writeback_control *wbc) |
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{ |
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struct gfs2_inode *ip = GFS2_I(mapping->host); |
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struct gfs2_sbd *sdp = GFS2_SB(mapping->host); |
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int ret; |
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|
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ret = gfs2_write_cache_jdata(mapping, wbc); |
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if (ret == 0 && wbc->sync_mode == WB_SYNC_ALL) { |
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gfs2_log_flush(sdp, ip->i_gl, GFS2_LOG_HEAD_FLUSH_NORMAL | |
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GFS2_LFC_JDATA_WPAGES); |
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ret = gfs2_write_cache_jdata(mapping, wbc); |
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} |
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return ret; |
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} |
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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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u64 dsize = i_size_read(&ip->i_inode); |
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void *kaddr; |
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int error; |
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|
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/* |
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* Due to the order of unstuffing files and ->fault(), 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, 0, PAGE_SIZE); |
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SetPageUptodate(page); |
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return 0; |
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} |
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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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|
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kaddr = kmap_atomic(page); |
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if (dsize > gfs2_max_stuffed_size(ip)) |
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dsize = gfs2_max_stuffed_size(ip); |
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memcpy(kaddr, dibh->b_data + sizeof(struct gfs2_dinode), dsize); |
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memset(kaddr + dsize, 0, PAGE_SIZE - dsize); |
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kunmap_atomic(kaddr); |
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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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static int __gfs2_readpage(void *file, struct page *page) |
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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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int error; |
|
|
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if (!gfs2_is_jdata(ip) || |
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(i_blocksize(inode) == PAGE_SIZE && !page_has_buffers(page))) { |
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error = iomap_readpage(page, &gfs2_iomap_ops); |
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} else if (gfs2_is_stuffed(ip)) { |
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error = stuffed_readpage(ip, page); |
|
unlock_page(page); |
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} else { |
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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 |
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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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return __gfs2_readpage(file, page); |
|
} |
|
|
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/** |
|
* gfs2_internal_read - read an internal file |
|
* @ip: The gfs2 inode |
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* @buf: The buffer to fill |
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* @pos: The file position |
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* @size: The amount to read |
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* |
|
*/ |
|
|
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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; |
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unsigned amt; |
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struct page *page; |
|
void *p; |
|
|
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do { |
|
amt = size - copied; |
|
if (offset + size > PAGE_SIZE) |
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amt = PAGE_SIZE - offset; |
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page = read_cache_page(mapping, index, __gfs2_readpage, NULL); |
|
if (IS_ERR(page)) |
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return PTR_ERR(page); |
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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 |
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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; |
|
}
|
|
|