From a549984b8c95acbecefd1fdd4bfdbea4d29b0588 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Sat, 11 May 2013 19:07:42 -0400 Subject: ext4: revert "ext4: use io_end for multiple bios" This reverts commit 4eec708d263f0ee10861d69251708a225b64cac7. Multiple users have reported crashes which is apparently caused by this commit. Thanks to Dmitry Monakhov for bisecting it. Signed-off-by: "Theodore Ts'o" Cc: Dmitry Monakhov Cc: Jan Kara --- fs/ext4/inode.c | 85 ++++++++++++++++++++++++++------------------------------- 1 file changed, 38 insertions(+), 47 deletions(-) (limited to 'fs/ext4/inode.c') diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 793d44b84d7f..d66656992358 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -1487,10 +1487,7 @@ static int mpage_da_submit_io(struct mpage_da_data *mpd, struct ext4_io_submit io_submit; BUG_ON(mpd->next_page <= mpd->first_page); - ext4_io_submit_init(&io_submit, mpd->wbc); - io_submit.io_end = ext4_init_io_end(inode, GFP_NOFS); - if (!io_submit.io_end) - return -ENOMEM; + memset(&io_submit, 0, sizeof(io_submit)); /* * We need to start from the first_page to the next_page - 1 * to make sure we also write the mapped dirty buffer_heads. @@ -1578,8 +1575,6 @@ static int mpage_da_submit_io(struct mpage_da_data *mpd, pagevec_release(&pvec); } ext4_io_submit(&io_submit); - /* Drop io_end reference we got from init */ - ext4_put_io_end_defer(io_submit.io_end); return ret; } @@ -2238,16 +2233,9 @@ static int ext4_writepage(struct page *page, */ return __ext4_journalled_writepage(page, len); - ext4_io_submit_init(&io_submit, wbc); - io_submit.io_end = ext4_init_io_end(inode, GFP_NOFS); - if (!io_submit.io_end) { - redirty_page_for_writepage(wbc, page); - return -ENOMEM; - } + memset(&io_submit, 0, sizeof(io_submit)); ret = ext4_bio_write_page(&io_submit, page, len, wbc); ext4_io_submit(&io_submit); - /* Drop io_end reference we got from init */ - ext4_put_io_end_defer(io_submit.io_end); return ret; } @@ -3078,13 +3066,9 @@ static void ext4_end_io_dio(struct kiocb *iocb, loff_t offset, struct inode *inode = file_inode(iocb->ki_filp); ext4_io_end_t *io_end = iocb->private; - /* if not async direct IO just return */ - if (!io_end) { - inode_dio_done(inode); - if (is_async) - aio_complete(iocb, ret, 0); - return; - } + /* if not async direct IO or dio with 0 bytes write, just return */ + if (!io_end || !size) + goto out; ext_debug("ext4_end_io_dio(): io_end 0x%p " "for inode %lu, iocb 0x%p, offset %llu, size %zd\n", @@ -3092,13 +3076,25 @@ static void ext4_end_io_dio(struct kiocb *iocb, loff_t offset, size); iocb->private = NULL; + + /* if not aio dio with unwritten extents, just free io and return */ + if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) { + ext4_free_io_end(io_end); +out: + inode_dio_done(inode); + if (is_async) + aio_complete(iocb, ret, 0); + return; + } + io_end->offset = offset; io_end->size = size; if (is_async) { io_end->iocb = iocb; io_end->result = ret; } - ext4_put_io_end_defer(io_end); + + ext4_add_complete_io(io_end); } /* @@ -3132,7 +3128,6 @@ static ssize_t ext4_ext_direct_IO(int rw, struct kiocb *iocb, get_block_t *get_block_func = NULL; int dio_flags = 0; loff_t final_size = offset + count; - ext4_io_end_t *io_end = NULL; /* Use the old path for reads and writes beyond i_size. */ if (rw != WRITE || final_size > inode->i_size) @@ -3171,16 +3166,13 @@ static ssize_t ext4_ext_direct_IO(int rw, struct kiocb *iocb, iocb->private = NULL; ext4_inode_aio_set(inode, NULL); if (!is_sync_kiocb(iocb)) { - io_end = ext4_init_io_end(inode, GFP_NOFS); + ext4_io_end_t *io_end = ext4_init_io_end(inode, GFP_NOFS); if (!io_end) { ret = -ENOMEM; goto retake_lock; } io_end->flag |= EXT4_IO_END_DIRECT; - /* - * Grab reference for DIO. Will be dropped in ext4_end_io_dio() - */ - iocb->private = ext4_get_io_end(io_end); + iocb->private = io_end; /* * we save the io structure for current async direct * IO, so that later ext4_map_blocks() could flag the @@ -3204,27 +3196,26 @@ static ssize_t ext4_ext_direct_IO(int rw, struct kiocb *iocb, NULL, dio_flags); + if (iocb->private) + ext4_inode_aio_set(inode, NULL); /* - * Put our reference to io_end. This can free the io_end structure e.g. - * in sync IO case or in case of error. It can even perform extent - * conversion if all bios we submitted finished before we got here. - * Note that in that case iocb->private can be already set to NULL - * here. + * The io_end structure takes a reference to the inode, that + * structure needs to be destroyed and the reference to the + * inode need to be dropped, when IO is complete, even with 0 + * byte write, or failed. + * + * In the successful AIO DIO case, the io_end structure will + * be destroyed and the reference to the inode will be dropped + * after the end_io call back function is called. + * + * In the case there is 0 byte write, or error case, since VFS + * direct IO won't invoke the end_io call back function, we + * need to free the end_io structure here. */ - if (io_end) { - ext4_inode_aio_set(inode, NULL); - ext4_put_io_end(io_end); - /* - * In case of error or no write ext4_end_io_dio() was not - * called so we have to put iocb's reference. - */ - if (ret <= 0 && ret != -EIOCBQUEUED) { - WARN_ON(iocb->private != io_end); - ext4_put_io_end(io_end); - iocb->private = NULL; - } - } - if (ret > 0 && !overwrite && ext4_test_inode_state(inode, + if (ret != -EIOCBQUEUED && ret <= 0 && iocb->private) { + ext4_free_io_end(iocb->private); + iocb->private = NULL; + } else if (ret > 0 && !overwrite && ext4_test_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN)) { int err; /* -- cgit v1.2.3