700 lines
21 KiB
C
700 lines
21 KiB
C
// SPDX-License-Identifier: LGPL-2.1
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/*
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* Copyright (c) 2008,2009 NEC Software Tohoku, Ltd.
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* Written by Takashi Sato <t-sato@yk.jp.nec.com>
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* Akira Fujita <a-fujita@rs.jp.nec.com>
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*/
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#include <linux/fs.h>
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#include <linux/quotaops.h>
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#include <linux/slab.h>
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#include "ext4_jbd2.h"
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#include "ext4.h"
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#include "ext4_extents.h"
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/**
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* get_ext_path() - Find an extent path for designated logical block number.
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* @inode: inode to be searched
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* @lblock: logical block number to find an extent path
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* @ppath: pointer to an extent path pointer (for output)
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*
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* ext4_find_extent wrapper. Return 0 on success, or a negative error value
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* on failure.
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*/
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static inline int
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get_ext_path(struct inode *inode, ext4_lblk_t lblock,
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struct ext4_ext_path **ppath)
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{
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struct ext4_ext_path *path;
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path = ext4_find_extent(inode, lblock, ppath, EXT4_EX_NOCACHE);
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if (IS_ERR(path))
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return PTR_ERR(path);
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if (path[ext_depth(inode)].p_ext == NULL) {
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ext4_ext_drop_refs(path);
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kfree(path);
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*ppath = NULL;
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return -ENODATA;
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}
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*ppath = path;
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return 0;
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}
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/**
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* ext4_double_down_write_data_sem() - write lock two inodes's i_data_sem
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* @first: inode to be locked
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* @second: inode to be locked
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*
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* Acquire write lock of i_data_sem of the two inodes
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*/
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void
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ext4_double_down_write_data_sem(struct inode *first, struct inode *second)
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{
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if (first < second) {
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down_write(&EXT4_I(first)->i_data_sem);
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down_write_nested(&EXT4_I(second)->i_data_sem, I_DATA_SEM_OTHER);
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} else {
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down_write(&EXT4_I(second)->i_data_sem);
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down_write_nested(&EXT4_I(first)->i_data_sem, I_DATA_SEM_OTHER);
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}
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}
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/**
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* ext4_double_up_write_data_sem - Release two inodes' write lock of i_data_sem
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*
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* @orig_inode: original inode structure to be released its lock first
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* @donor_inode: donor inode structure to be released its lock second
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* Release write lock of i_data_sem of two inodes (orig and donor).
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*/
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void
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ext4_double_up_write_data_sem(struct inode *orig_inode,
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struct inode *donor_inode)
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{
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up_write(&EXT4_I(orig_inode)->i_data_sem);
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up_write(&EXT4_I(donor_inode)->i_data_sem);
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}
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/**
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* mext_check_coverage - Check that all extents in range has the same type
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*
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* @inode: inode in question
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* @from: block offset of inode
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* @count: block count to be checked
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* @unwritten: extents expected to be unwritten
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* @err: pointer to save error value
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*
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* Return 1 if all extents in range has expected type, and zero otherwise.
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*/
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static int
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mext_check_coverage(struct inode *inode, ext4_lblk_t from, ext4_lblk_t count,
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int unwritten, int *err)
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{
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struct ext4_ext_path *path = NULL;
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struct ext4_extent *ext;
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int ret = 0;
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ext4_lblk_t last = from + count;
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while (from < last) {
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*err = get_ext_path(inode, from, &path);
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if (*err)
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goto out;
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ext = path[ext_depth(inode)].p_ext;
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if (unwritten != ext4_ext_is_unwritten(ext))
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goto out;
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from += ext4_ext_get_actual_len(ext);
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ext4_ext_drop_refs(path);
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}
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ret = 1;
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out:
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ext4_ext_drop_refs(path);
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kfree(path);
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return ret;
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}
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/**
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* mext_page_double_lock - Grab and lock pages on both @inode1 and @inode2
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*
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* @inode1: the inode structure
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* @inode2: the inode structure
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* @index1: page index
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* @index2: page index
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* @page: result page vector
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*
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* Grab two locked pages for inode's by inode order
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*/
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static int
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mext_page_double_lock(struct inode *inode1, struct inode *inode2,
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pgoff_t index1, pgoff_t index2, struct page *page[2])
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{
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struct address_space *mapping[2];
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unsigned fl = AOP_FLAG_NOFS;
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BUG_ON(!inode1 || !inode2);
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if (inode1 < inode2) {
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mapping[0] = inode1->i_mapping;
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mapping[1] = inode2->i_mapping;
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} else {
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swap(index1, index2);
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mapping[0] = inode2->i_mapping;
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mapping[1] = inode1->i_mapping;
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}
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page[0] = grab_cache_page_write_begin(mapping[0], index1, fl);
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if (!page[0])
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return -ENOMEM;
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page[1] = grab_cache_page_write_begin(mapping[1], index2, fl);
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if (!page[1]) {
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unlock_page(page[0]);
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put_page(page[0]);
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return -ENOMEM;
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}
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/*
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* grab_cache_page_write_begin() may not wait on page's writeback if
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* BDI not demand that. But it is reasonable to be very conservative
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* here and explicitly wait on page's writeback
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*/
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wait_on_page_writeback(page[0]);
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wait_on_page_writeback(page[1]);
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if (inode1 > inode2)
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swap(page[0], page[1]);
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return 0;
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}
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/* Force page buffers uptodate w/o dropping page's lock */
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static int
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mext_page_mkuptodate(struct page *page, unsigned from, unsigned to)
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{
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struct inode *inode = page->mapping->host;
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sector_t block;
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struct buffer_head *bh, *head, *arr[MAX_BUF_PER_PAGE];
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unsigned int blocksize, block_start, block_end;
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int i, err, nr = 0, partial = 0;
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BUG_ON(!PageLocked(page));
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BUG_ON(PageWriteback(page));
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if (PageUptodate(page))
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return 0;
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blocksize = i_blocksize(inode);
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if (!page_has_buffers(page))
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create_empty_buffers(page, blocksize, 0);
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head = page_buffers(page);
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block = (sector_t)page->index << (PAGE_SHIFT - inode->i_blkbits);
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for (bh = head, block_start = 0; bh != head || !block_start;
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block++, block_start = block_end, bh = bh->b_this_page) {
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block_end = block_start + blocksize;
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if (block_end <= from || block_start >= to) {
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if (!buffer_uptodate(bh))
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partial = 1;
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continue;
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}
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if (buffer_uptodate(bh))
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continue;
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if (!buffer_mapped(bh)) {
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err = ext4_get_block(inode, block, bh, 0);
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if (err) {
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SetPageError(page);
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return err;
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}
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if (!buffer_mapped(bh)) {
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zero_user(page, block_start, blocksize);
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set_buffer_uptodate(bh);
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continue;
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}
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}
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BUG_ON(nr >= MAX_BUF_PER_PAGE);
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arr[nr++] = bh;
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}
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/* No io required */
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if (!nr)
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goto out;
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for (i = 0; i < nr; i++) {
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bh = arr[i];
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if (!bh_uptodate_or_lock(bh)) {
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err = bh_submit_read(bh);
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if (err)
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return err;
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}
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}
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out:
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if (!partial)
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SetPageUptodate(page);
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return 0;
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}
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/**
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* move_extent_per_page - Move extent data per page
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*
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* @o_filp: file structure of original file
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* @donor_inode: donor inode
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* @orig_page_offset: page index on original file
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* @donor_page_offset: page index on donor file
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* @data_offset_in_page: block index where data swapping starts
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* @block_len_in_page: the number of blocks to be swapped
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* @unwritten: orig extent is unwritten or not
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* @err: pointer to save return value
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*
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* Save the data in original inode blocks and replace original inode extents
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* with donor inode extents by calling ext4_swap_extents().
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* Finally, write out the saved data in new original inode blocks. Return
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* replaced block count.
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*/
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static int
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move_extent_per_page(struct file *o_filp, struct inode *donor_inode,
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pgoff_t orig_page_offset, pgoff_t donor_page_offset,
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int data_offset_in_page,
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int block_len_in_page, int unwritten, int *err)
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{
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struct inode *orig_inode = file_inode(o_filp);
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struct page *pagep[2] = {NULL, NULL};
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handle_t *handle;
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ext4_lblk_t orig_blk_offset, donor_blk_offset;
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unsigned long blocksize = orig_inode->i_sb->s_blocksize;
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unsigned int tmp_data_size, data_size, replaced_size;
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int i, err2, jblocks, retries = 0;
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int replaced_count = 0;
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int from = data_offset_in_page << orig_inode->i_blkbits;
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int blocks_per_page = PAGE_SIZE >> orig_inode->i_blkbits;
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struct super_block *sb = orig_inode->i_sb;
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struct buffer_head *bh = NULL;
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/*
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* It needs twice the amount of ordinary journal buffers because
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* inode and donor_inode may change each different metadata blocks.
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*/
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again:
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*err = 0;
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jblocks = ext4_writepage_trans_blocks(orig_inode) * 2;
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handle = ext4_journal_start(orig_inode, EXT4_HT_MOVE_EXTENTS, jblocks);
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if (IS_ERR(handle)) {
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*err = PTR_ERR(handle);
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return 0;
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}
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orig_blk_offset = orig_page_offset * blocks_per_page +
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data_offset_in_page;
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donor_blk_offset = donor_page_offset * blocks_per_page +
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data_offset_in_page;
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/* Calculate data_size */
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if ((orig_blk_offset + block_len_in_page - 1) ==
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((orig_inode->i_size - 1) >> orig_inode->i_blkbits)) {
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/* Replace the last block */
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tmp_data_size = orig_inode->i_size & (blocksize - 1);
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/*
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* If data_size equal zero, it shows data_size is multiples of
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* blocksize. So we set appropriate value.
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*/
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if (tmp_data_size == 0)
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tmp_data_size = blocksize;
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data_size = tmp_data_size +
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((block_len_in_page - 1) << orig_inode->i_blkbits);
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} else
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data_size = block_len_in_page << orig_inode->i_blkbits;
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replaced_size = data_size;
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*err = mext_page_double_lock(orig_inode, donor_inode, orig_page_offset,
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donor_page_offset, pagep);
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if (unlikely(*err < 0))
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goto stop_journal;
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/*
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* If orig extent was unwritten it can become initialized
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* at any time after i_data_sem was dropped, in order to
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* serialize with delalloc we have recheck extent while we
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* hold page's lock, if it is still the case data copy is not
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* necessary, just swap data blocks between orig and donor.
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*/
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if (unwritten) {
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ext4_double_down_write_data_sem(orig_inode, donor_inode);
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/* If any of extents in range became initialized we have to
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* fallback to data copying */
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unwritten = mext_check_coverage(orig_inode, orig_blk_offset,
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block_len_in_page, 1, err);
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if (*err)
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goto drop_data_sem;
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unwritten &= mext_check_coverage(donor_inode, donor_blk_offset,
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block_len_in_page, 1, err);
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if (*err)
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goto drop_data_sem;
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if (!unwritten) {
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ext4_double_up_write_data_sem(orig_inode, donor_inode);
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goto data_copy;
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}
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if ((page_has_private(pagep[0]) &&
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!try_to_release_page(pagep[0], 0)) ||
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(page_has_private(pagep[1]) &&
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!try_to_release_page(pagep[1], 0))) {
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*err = -EBUSY;
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goto drop_data_sem;
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}
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replaced_count = ext4_swap_extents(handle, orig_inode,
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donor_inode, orig_blk_offset,
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donor_blk_offset,
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block_len_in_page, 1, err);
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drop_data_sem:
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ext4_double_up_write_data_sem(orig_inode, donor_inode);
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goto unlock_pages;
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}
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data_copy:
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*err = mext_page_mkuptodate(pagep[0], from, from + replaced_size);
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if (*err)
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goto unlock_pages;
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/* At this point all buffers in range are uptodate, old mapping layout
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* is no longer required, try to drop it now. */
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if ((page_has_private(pagep[0]) && !try_to_release_page(pagep[0], 0)) ||
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(page_has_private(pagep[1]) && !try_to_release_page(pagep[1], 0))) {
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*err = -EBUSY;
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goto unlock_pages;
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}
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ext4_double_down_write_data_sem(orig_inode, donor_inode);
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replaced_count = ext4_swap_extents(handle, orig_inode, donor_inode,
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orig_blk_offset, donor_blk_offset,
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block_len_in_page, 1, err);
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ext4_double_up_write_data_sem(orig_inode, donor_inode);
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if (*err) {
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if (replaced_count) {
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block_len_in_page = replaced_count;
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replaced_size =
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block_len_in_page << orig_inode->i_blkbits;
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} else
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goto unlock_pages;
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}
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/* Perform all necessary steps similar write_begin()/write_end()
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* but keeping in mind that i_size will not change */
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if (!page_has_buffers(pagep[0]))
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create_empty_buffers(pagep[0], 1 << orig_inode->i_blkbits, 0);
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bh = page_buffers(pagep[0]);
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for (i = 0; i < data_offset_in_page; i++)
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bh = bh->b_this_page;
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for (i = 0; i < block_len_in_page; i++) {
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*err = ext4_get_block(orig_inode, orig_blk_offset + i, bh, 0);
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if (*err < 0)
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break;
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bh = bh->b_this_page;
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}
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if (!*err)
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*err = block_commit_write(pagep[0], from, from + replaced_size);
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if (unlikely(*err < 0))
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goto repair_branches;
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/* Even in case of data=writeback it is reasonable to pin
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* inode to transaction, to prevent unexpected data loss */
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*err = ext4_jbd2_inode_add_write(handle, orig_inode,
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(loff_t)orig_page_offset << PAGE_SHIFT, replaced_size);
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unlock_pages:
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unlock_page(pagep[0]);
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put_page(pagep[0]);
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unlock_page(pagep[1]);
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put_page(pagep[1]);
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stop_journal:
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ext4_journal_stop(handle);
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if (*err == -ENOSPC &&
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ext4_should_retry_alloc(sb, &retries))
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goto again;
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/* Buffer was busy because probably is pinned to journal transaction,
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* force transaction commit may help to free it. */
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if (*err == -EBUSY && retries++ < 4 && EXT4_SB(sb)->s_journal &&
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jbd2_journal_force_commit_nested(EXT4_SB(sb)->s_journal))
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goto again;
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return replaced_count;
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repair_branches:
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/*
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* This should never ever happen!
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* Extents are swapped already, but we are not able to copy data.
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* Try to swap extents to it's original places
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*/
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ext4_double_down_write_data_sem(orig_inode, donor_inode);
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replaced_count = ext4_swap_extents(handle, donor_inode, orig_inode,
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orig_blk_offset, donor_blk_offset,
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block_len_in_page, 0, &err2);
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ext4_double_up_write_data_sem(orig_inode, donor_inode);
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if (replaced_count != block_len_in_page) {
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EXT4_ERROR_INODE_BLOCK(orig_inode, (sector_t)(orig_blk_offset),
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"Unable to copy data block,"
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" data will be lost.");
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*err = -EIO;
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}
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replaced_count = 0;
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goto unlock_pages;
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}
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/**
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* mext_check_arguments - Check whether move extent can be done
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*
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* @orig_inode: original inode
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* @donor_inode: donor inode
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* @orig_start: logical start offset in block for orig
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* @donor_start: logical start offset in block for donor
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* @len: the number of blocks to be moved
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*
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* Check the arguments of ext4_move_extents() whether the files can be
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* exchanged with each other.
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* Return 0 on success, or a negative error value on failure.
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*/
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static int
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mext_check_arguments(struct inode *orig_inode,
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struct inode *donor_inode, __u64 orig_start,
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__u64 donor_start, __u64 *len)
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{
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__u64 orig_eof, donor_eof;
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unsigned int blkbits = orig_inode->i_blkbits;
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unsigned int blocksize = 1 << blkbits;
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orig_eof = (i_size_read(orig_inode) + blocksize - 1) >> blkbits;
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donor_eof = (i_size_read(donor_inode) + blocksize - 1) >> blkbits;
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if (donor_inode->i_mode & (S_ISUID|S_ISGID)) {
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ext4_debug("ext4 move extent: suid or sgid is set"
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" to donor file [ino:orig %lu, donor %lu]\n",
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orig_inode->i_ino, donor_inode->i_ino);
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return -EINVAL;
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}
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if (IS_IMMUTABLE(donor_inode) || IS_APPEND(donor_inode))
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return -EPERM;
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/* Ext4 move extent does not support swapfile */
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if (IS_SWAPFILE(orig_inode) || IS_SWAPFILE(donor_inode)) {
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ext4_debug("ext4 move extent: The argument files should "
|
|
"not be swapfile [ino:orig %lu, donor %lu]\n",
|
|
orig_inode->i_ino, donor_inode->i_ino);
|
|
return -EBUSY;
|
|
}
|
|
|
|
if (ext4_is_quota_file(orig_inode) && ext4_is_quota_file(donor_inode)) {
|
|
ext4_debug("ext4 move extent: The argument files should "
|
|
"not be quota files [ino:orig %lu, donor %lu]\n",
|
|
orig_inode->i_ino, donor_inode->i_ino);
|
|
return -EBUSY;
|
|
}
|
|
|
|
/* Ext4 move extent supports only extent based file */
|
|
if (!(ext4_test_inode_flag(orig_inode, EXT4_INODE_EXTENTS))) {
|
|
ext4_debug("ext4 move extent: orig file is not extents "
|
|
"based file [ino:orig %lu]\n", orig_inode->i_ino);
|
|
return -EOPNOTSUPP;
|
|
} else if (!(ext4_test_inode_flag(donor_inode, EXT4_INODE_EXTENTS))) {
|
|
ext4_debug("ext4 move extent: donor file is not extents "
|
|
"based file [ino:donor %lu]\n", donor_inode->i_ino);
|
|
return -EOPNOTSUPP;
|
|
}
|
|
|
|
if ((!orig_inode->i_size) || (!donor_inode->i_size)) {
|
|
ext4_debug("ext4 move extent: File size is 0 byte\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Start offset should be same */
|
|
if ((orig_start & ~(PAGE_MASK >> orig_inode->i_blkbits)) !=
|
|
(donor_start & ~(PAGE_MASK >> orig_inode->i_blkbits))) {
|
|
ext4_debug("ext4 move extent: orig and donor's start "
|
|
"offsets are not aligned [ino:orig %lu, donor %lu]\n",
|
|
orig_inode->i_ino, donor_inode->i_ino);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if ((orig_start >= EXT_MAX_BLOCKS) ||
|
|
(donor_start >= EXT_MAX_BLOCKS) ||
|
|
(*len > EXT_MAX_BLOCKS) ||
|
|
(donor_start + *len >= EXT_MAX_BLOCKS) ||
|
|
(orig_start + *len >= EXT_MAX_BLOCKS)) {
|
|
ext4_debug("ext4 move extent: Can't handle over [%u] blocks "
|
|
"[ino:orig %lu, donor %lu]\n", EXT_MAX_BLOCKS,
|
|
orig_inode->i_ino, donor_inode->i_ino);
|
|
return -EINVAL;
|
|
}
|
|
if (orig_eof <= orig_start)
|
|
*len = 0;
|
|
else if (orig_eof < orig_start + *len - 1)
|
|
*len = orig_eof - orig_start;
|
|
if (donor_eof <= donor_start)
|
|
*len = 0;
|
|
else if (donor_eof < donor_start + *len - 1)
|
|
*len = donor_eof - donor_start;
|
|
if (!*len) {
|
|
ext4_debug("ext4 move extent: len should not be 0 "
|
|
"[ino:orig %lu, donor %lu]\n", orig_inode->i_ino,
|
|
donor_inode->i_ino);
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* ext4_move_extents - Exchange the specified range of a file
|
|
*
|
|
* @o_filp: file structure of the original file
|
|
* @d_filp: file structure of the donor file
|
|
* @orig_blk: start offset in block for orig
|
|
* @donor_blk: start offset in block for donor
|
|
* @len: the number of blocks to be moved
|
|
* @moved_len: moved block length
|
|
*
|
|
* This function returns 0 and moved block length is set in moved_len
|
|
* if succeed, otherwise returns error value.
|
|
*
|
|
*/
|
|
int
|
|
ext4_move_extents(struct file *o_filp, struct file *d_filp, __u64 orig_blk,
|
|
__u64 donor_blk, __u64 len, __u64 *moved_len)
|
|
{
|
|
struct inode *orig_inode = file_inode(o_filp);
|
|
struct inode *donor_inode = file_inode(d_filp);
|
|
struct ext4_ext_path *path = NULL;
|
|
int blocks_per_page = PAGE_SIZE >> orig_inode->i_blkbits;
|
|
ext4_lblk_t o_end, o_start = orig_blk;
|
|
ext4_lblk_t d_start = donor_blk;
|
|
int ret;
|
|
|
|
if (orig_inode->i_sb != donor_inode->i_sb) {
|
|
ext4_debug("ext4 move extent: The argument files "
|
|
"should be in same FS [ino:orig %lu, donor %lu]\n",
|
|
orig_inode->i_ino, donor_inode->i_ino);
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* orig and donor should be different inodes */
|
|
if (orig_inode == donor_inode) {
|
|
ext4_debug("ext4 move extent: The argument files should not "
|
|
"be same inode [ino:orig %lu, donor %lu]\n",
|
|
orig_inode->i_ino, donor_inode->i_ino);
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Regular file check */
|
|
if (!S_ISREG(orig_inode->i_mode) || !S_ISREG(donor_inode->i_mode)) {
|
|
ext4_debug("ext4 move extent: The argument files should be "
|
|
"regular file [ino:orig %lu, donor %lu]\n",
|
|
orig_inode->i_ino, donor_inode->i_ino);
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* TODO: it's not obvious how to swap blocks for inodes with full
|
|
journaling enabled */
|
|
if (ext4_should_journal_data(orig_inode) ||
|
|
ext4_should_journal_data(donor_inode)) {
|
|
ext4_msg(orig_inode->i_sb, KERN_ERR,
|
|
"Online defrag not supported with data journaling");
|
|
return -EOPNOTSUPP;
|
|
}
|
|
|
|
if (IS_ENCRYPTED(orig_inode) || IS_ENCRYPTED(donor_inode)) {
|
|
ext4_msg(orig_inode->i_sb, KERN_ERR,
|
|
"Online defrag not supported for encrypted files");
|
|
return -EOPNOTSUPP;
|
|
}
|
|
|
|
/* Protect orig and donor inodes against a truncate */
|
|
lock_two_nondirectories(orig_inode, donor_inode);
|
|
|
|
/* Wait for all existing dio workers */
|
|
inode_dio_wait(orig_inode);
|
|
inode_dio_wait(donor_inode);
|
|
|
|
/* Protect extent tree against block allocations via delalloc */
|
|
ext4_double_down_write_data_sem(orig_inode, donor_inode);
|
|
/* Check the filesystem environment whether move_extent can be done */
|
|
ret = mext_check_arguments(orig_inode, donor_inode, orig_blk,
|
|
donor_blk, &len);
|
|
if (ret)
|
|
goto out;
|
|
o_end = o_start + len;
|
|
|
|
while (o_start < o_end) {
|
|
struct ext4_extent *ex;
|
|
ext4_lblk_t cur_blk, next_blk;
|
|
pgoff_t orig_page_index, donor_page_index;
|
|
int offset_in_page;
|
|
int unwritten, cur_len;
|
|
|
|
ret = get_ext_path(orig_inode, o_start, &path);
|
|
if (ret)
|
|
goto out;
|
|
ex = path[path->p_depth].p_ext;
|
|
next_blk = ext4_ext_next_allocated_block(path);
|
|
cur_blk = le32_to_cpu(ex->ee_block);
|
|
cur_len = ext4_ext_get_actual_len(ex);
|
|
/* Check hole before the start pos */
|
|
if (cur_blk + cur_len - 1 < o_start) {
|
|
if (next_blk == EXT_MAX_BLOCKS) {
|
|
o_start = o_end;
|
|
ret = -ENODATA;
|
|
goto out;
|
|
}
|
|
d_start += next_blk - o_start;
|
|
o_start = next_blk;
|
|
continue;
|
|
/* Check hole after the start pos */
|
|
} else if (cur_blk > o_start) {
|
|
/* Skip hole */
|
|
d_start += cur_blk - o_start;
|
|
o_start = cur_blk;
|
|
/* Extent inside requested range ?*/
|
|
if (cur_blk >= o_end)
|
|
goto out;
|
|
} else { /* in_range(o_start, o_blk, o_len) */
|
|
cur_len += cur_blk - o_start;
|
|
}
|
|
unwritten = ext4_ext_is_unwritten(ex);
|
|
if (o_end - o_start < cur_len)
|
|
cur_len = o_end - o_start;
|
|
|
|
orig_page_index = o_start >> (PAGE_SHIFT -
|
|
orig_inode->i_blkbits);
|
|
donor_page_index = d_start >> (PAGE_SHIFT -
|
|
donor_inode->i_blkbits);
|
|
offset_in_page = o_start % blocks_per_page;
|
|
if (cur_len > blocks_per_page- offset_in_page)
|
|
cur_len = blocks_per_page - offset_in_page;
|
|
/*
|
|
* Up semaphore to avoid following problems:
|
|
* a. transaction deadlock among ext4_journal_start,
|
|
* ->write_begin via pagefault, and jbd2_journal_commit
|
|
* b. racing with ->readpage, ->write_begin, and ext4_get_block
|
|
* in move_extent_per_page
|
|
*/
|
|
ext4_double_up_write_data_sem(orig_inode, donor_inode);
|
|
/* Swap original branches with new branches */
|
|
move_extent_per_page(o_filp, donor_inode,
|
|
orig_page_index, donor_page_index,
|
|
offset_in_page, cur_len,
|
|
unwritten, &ret);
|
|
ext4_double_down_write_data_sem(orig_inode, donor_inode);
|
|
if (ret < 0)
|
|
break;
|
|
o_start += cur_len;
|
|
d_start += cur_len;
|
|
}
|
|
*moved_len = o_start - orig_blk;
|
|
if (*moved_len > len)
|
|
*moved_len = len;
|
|
|
|
out:
|
|
if (*moved_len) {
|
|
ext4_discard_preallocations(orig_inode);
|
|
ext4_discard_preallocations(donor_inode);
|
|
}
|
|
|
|
ext4_ext_drop_refs(path);
|
|
kfree(path);
|
|
ext4_double_up_write_data_sem(orig_inode, donor_inode);
|
|
unlock_two_nondirectories(orig_inode, donor_inode);
|
|
|
|
return ret;
|
|
}
|