From d0b2f91bede3bd5e3d24dd6803e56eee959c1797 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Thu, 20 Oct 2016 00:10:27 -0300 Subject: Linux-libre 4.8.2-gnu --- fs/gfs2/aops.c | 49 ++++++++++++++++++++++++++++++++++--------------- 1 file changed, 34 insertions(+), 15 deletions(-) (limited to 'fs/gfs2/aops.c') diff --git a/fs/gfs2/aops.c b/fs/gfs2/aops.c index 37b7bc14c..82df36886 100644 --- a/fs/gfs2/aops.c +++ b/fs/gfs2/aops.c @@ -140,6 +140,32 @@ static int gfs2_writepage(struct page *page, struct writeback_control *wbc) return nobh_writepage(page, gfs2_get_block_noalloc, wbc); } +/* This is the same as calling block_write_full_page, but it also + * writes pages outside of i_size + */ +int gfs2_write_full_page(struct page *page, get_block_t *get_block, + struct writeback_control *wbc) +{ + struct inode * const inode = page->mapping->host; + loff_t i_size = i_size_read(inode); + const pgoff_t end_index = i_size >> PAGE_SHIFT; + unsigned offset; + + /* + * The page straddles i_size. It must be zeroed out on each and every + * writepage invocation because it may be mmapped. "A file is mapped + * in multiples of the page size. For a file that is not a multiple of + * the page size, the remaining memory is zeroed when mapped, and + * writes to that region are not written out to the file." + */ + offset = i_size & (PAGE_SIZE-1); + if (page->index == end_index && offset) + zero_user_segment(page, offset, PAGE_SIZE); + + return __block_write_full_page(inode, page, get_block, wbc, + end_buffer_async_write); +} + /** * __gfs2_jdata_writepage - The core of jdata writepage * @page: The page to write @@ -165,7 +191,7 @@ static int __gfs2_jdata_writepage(struct page *page, struct writeback_control *w } gfs2_page_add_databufs(ip, page, 0, sdp->sd_vfs->s_blocksize-1); } - return block_write_full_page(page, gfs2_get_block_noalloc, wbc); + return gfs2_write_full_page(page, gfs2_get_block_noalloc, wbc); } /** @@ -180,27 +206,20 @@ static int __gfs2_jdata_writepage(struct page *page, struct writeback_control *w static int gfs2_jdata_writepage(struct page *page, struct writeback_control *wbc) { struct inode *inode = page->mapping->host; + struct gfs2_inode *ip = GFS2_I(inode); struct gfs2_sbd *sdp = GFS2_SB(inode); int ret; - int done_trans = 0; - if (PageChecked(page)) { - if (wbc->sync_mode != WB_SYNC_ALL) - goto out_ignore; - ret = gfs2_trans_begin(sdp, RES_DINODE + 1, 0); - if (ret) - goto out_ignore; - done_trans = 1; - } - ret = gfs2_writepage_common(page, wbc); - if (ret > 0) - ret = __gfs2_jdata_writepage(page, wbc); - if (done_trans) - gfs2_trans_end(sdp); + if (gfs2_assert_withdraw(sdp, gfs2_glock_is_held_excl(ip->i_gl))) + goto out; + if (PageChecked(page) || current->journal_info) + goto out_ignore; + ret = __gfs2_jdata_writepage(page, wbc); return ret; out_ignore: redirty_page_for_writepage(wbc, page); +out: unlock_page(page); return 0; } -- cgit v1.2.3-54-g00ecf