Re: [f2fs-dev][PATCH V2 4/6] f2fs: Key functions to handle inline data

From: Jaegeuk Kim
Date: Fri Nov 15 2013 - 02:50:13 EST


Hi Huajun,

[snip]

> +static int __f2fs_convert_inline_data(struct inode *inode, struct page *page)
> +{
> + int err;
> + struct page *ipage;
> + struct dnode_of_data dn;
> + void *src_addr, *dst_addr;
> + block_t old_blk_addr, new_blk_addr;
> + struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
> +
> + f2fs_lock_op(sbi);
> + ipage = get_node_page(sbi, inode->i_ino);
> + if (IS_ERR(ipage))
> + return PTR_ERR(ipage);
> +
> + /*
> + * i_addr[0] is not used for inline data,
> + * so reserving new block will not destroy inline data
> + */
> + set_new_dnode(&dn, inode, ipage, ipage, 0);
> + err = f2fs_reserve_block(&dn, 0);
> + if (err) {
> + f2fs_put_page(ipage, 1);
> + f2fs_unlock_op(sbi);
> + return err;
> + }
> +
> + src_addr = inline_data_addr(ipage);
> + dst_addr = page_address(page);
> + zero_user_segment(page, 0, PAGE_CACHE_SIZE);
> +
> + /* Copy the whole inline data block */
> + memcpy(dst_addr, src_addr, MAX_INLINE_DATA);
> +
> + /* write data page to try to make data consistent */
> + old_blk_addr = dn.data_blkaddr;
> + set_page_writeback(page);
> + write_data_page(inode, page, &dn,
> + old_blk_addr, &new_blk_addr);
> + update_extent_cache(new_blk_addr, &dn);
> + f2fs_wait_on_page_writeback(page, DATA, true);
> +
> + /* clear inline data and flag after data writeback */
> + zero_user_segment(ipage, INLINE_DATA_OFFSET,
> + INLINE_DATA_OFFSET + MAX_INLINE_DATA);
> + clear_inode_flag(F2FS_I(inode), FI_INLINE_DATA);
> +
> + sync_inode_page(&dn);
> + f2fs_put_page(ipage, 1);

Again, it seems that you missed what I mentioned.
If we write the inlined data block only, we cannot recover the data
block after SPO.
In order to avoid that, we should write its dnode block too by
triggering sync_node_pages(ino) at this point as similar as fsync
routine.

Thanks,

--
Jaegeuk Kim
Samsung

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