If we're punching a hole in a THP, we need to remove the per-page iomap data as the THP is about to be split and each page will need its own. This means that writepage can now come across a page with no iop allocated, so remove the assertions that there is already one, and just create one (with the Uptodate bits set) if there isn't one.
Signed-off-by: Matthew Wilcox (Oracle) <[email protected]> --- fs/iomap/buffered-io.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index 5cc0343b6a8e..9ea162617398 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -54,6 +54,8 @@ iomap_page_create(struct inode *inode, struct page *page) iop = kzalloc(struct_size(iop, uptodate, BITS_TO_LONGS(nr_blocks)), GFP_NOFS | __GFP_NOFAIL); spin_lock_init(&iop->uptodate_lock); + if (PageUptodate(page)) + bitmap_fill(iop->uptodate, nr_blocks); attach_page_private(page, iop); return iop; } @@ -483,10 +485,17 @@ iomap_invalidatepage(struct page *page, unsigned int offset, unsigned int len) * If we are invalidating the entire page, clear the dirty state from it * and release it to avoid unnecessary buildup of the LRU. */ - if (offset == 0 && len == PAGE_SIZE) { + if (offset == 0 && len == thp_size(page)) { WARN_ON_ONCE(PageWriteback(page)); cancel_dirty_page(page); iomap_page_release(page); + return; + } + + /* Punching a hole in a THP requires releasing the iop */ + if (PageTransHuge(page)) { + VM_BUG_ON_PAGE(!PageUptodate(page), page); + iomap_page_release(page); } } EXPORT_SYMBOL_GPL(iomap_invalidatepage); @@ -1043,14 +1052,13 @@ static void iomap_finish_page_writeback(struct inode *inode, struct page *page, int error, unsigned int len) { - struct iomap_page *iop = to_iomap_page(page); + struct iomap_page *iop = iomap_page_create(inode, page); if (error) { SetPageError(page); mapping_set_error(inode->i_mapping, -EIO); } - WARN_ON_ONCE(i_blocks_per_page(inode, page) > 1 && !iop); WARN_ON_ONCE(iop && atomic_read(&iop->write_count) <= 0); if (!iop || atomic_sub_and_test(len, &iop->write_count)) @@ -1340,14 +1348,13 @@ iomap_writepage_map(struct iomap_writepage_ctx *wpc, struct writeback_control *wbc, struct inode *inode, struct page *page, u64 end_offset) { - struct iomap_page *iop = to_iomap_page(page); + struct iomap_page *iop = iomap_page_create(inode, page); struct iomap_ioend *ioend, *next; unsigned len = i_blocksize(inode); u64 file_offset; /* file offset of page */ int error = 0, count = 0, i; LIST_HEAD(submit_list); - WARN_ON_ONCE(i_blocks_per_page(inode, page) > 1 && !iop); WARN_ON_ONCE(iop && atomic_read(&iop->write_count) != 0); /* -- 2.28.0
