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" <tytso@mit.edu>
Cc: Dmitry Monakhov <dmonakhov@openvz.org>
Cc: Jan Kara <jack@suse.cz>
diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
index 5929cd0..6626aba 100644
--- a/fs/ext4/page-io.c
+++ b/fs/ext4/page-io.c
@@ -61,28 +61,15 @@
cancel_work_sync(&EXT4_I(inode)->i_unwritten_work);
}
-static void ext4_release_io_end(ext4_io_end_t *io_end)
+void ext4_free_io_end(ext4_io_end_t *io)
{
- BUG_ON(!list_empty(&io_end->list));
- BUG_ON(io_end->flag & EXT4_IO_END_UNWRITTEN);
+ BUG_ON(!io);
+ BUG_ON(!list_empty(&io->list));
+ BUG_ON(io->flag & EXT4_IO_END_UNWRITTEN);
- if (atomic_dec_and_test(&EXT4_I(io_end->inode)->i_ioend_count))
- wake_up_all(ext4_ioend_wq(io_end->inode));
- if (io_end->flag & EXT4_IO_END_DIRECT)
- inode_dio_done(io_end->inode);
- if (io_end->iocb)
- aio_complete(io_end->iocb, io_end->result, 0);
- kmem_cache_free(io_end_cachep, io_end);
-}
-
-static void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
-{
- struct inode *inode = io_end->inode;
-
- io_end->flag &= ~EXT4_IO_END_UNWRITTEN;
- /* Wake up anyone waiting on unwritten extent conversion */
- if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten))
- wake_up_all(ext4_ioend_wq(inode));
+ if (atomic_dec_and_test(&EXT4_I(io->inode)->i_ioend_count))
+ wake_up_all(ext4_ioend_wq(io->inode));
+ kmem_cache_free(io_end_cachep, io);
}
/* check a range of space and convert unwritten extents to written. */
@@ -105,8 +92,13 @@
"(inode %lu, offset %llu, size %zd, error %d)",
inode->i_ino, offset, size, ret);
}
- ext4_clear_io_unwritten_flag(io);
- ext4_release_io_end(io);
+ /* Wake up anyone waiting on unwritten extent conversion */
+ if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten))
+ wake_up_all(ext4_ioend_wq(inode));
+ if (io->flag & EXT4_IO_END_DIRECT)
+ inode_dio_done(inode);
+ if (io->iocb)
+ aio_complete(io->iocb, io->result, 0);
return ret;
}
@@ -137,7 +129,7 @@
}
/* Add the io_end to per-inode completed end_io list. */
-static void ext4_add_complete_io(ext4_io_end_t *io_end)
+void ext4_add_complete_io(ext4_io_end_t *io_end)
{
struct ext4_inode_info *ei = EXT4_I(io_end->inode);
struct workqueue_struct *wq;
@@ -174,6 +166,8 @@
err = ext4_end_io(io);
if (unlikely(!ret && err))
ret = err;
+ io->flag &= ~EXT4_IO_END_UNWRITTEN;
+ ext4_free_io_end(io);
}
return ret;
}
@@ -205,43 +199,10 @@
atomic_inc(&EXT4_I(inode)->i_ioend_count);
io->inode = inode;
INIT_LIST_HEAD(&io->list);
- atomic_set(&io->count, 1);
}
return io;
}
-void ext4_put_io_end_defer(ext4_io_end_t *io_end)
-{
- if (atomic_dec_and_test(&io_end->count)) {
- if (!(io_end->flag & EXT4_IO_END_UNWRITTEN) || !io_end->size) {
- ext4_release_io_end(io_end);
- return;
- }
- ext4_add_complete_io(io_end);
- }
-}
-
-int ext4_put_io_end(ext4_io_end_t *io_end)
-{
- int err = 0;
-
- if (atomic_dec_and_test(&io_end->count)) {
- if (io_end->flag & EXT4_IO_END_UNWRITTEN) {
- err = ext4_convert_unwritten_extents(io_end->inode,
- io_end->offset, io_end->size);
- ext4_clear_io_unwritten_flag(io_end);
- }
- ext4_release_io_end(io_end);
- }
- return err;
-}
-
-ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end)
-{
- atomic_inc(&io_end->count);
- return io_end;
-}
-
/*
* Print an buffer I/O error compatible with the fs/buffer.c. This
* provides compatibility with dmesg scrapers that look for a specific
@@ -324,7 +285,12 @@
bi_sector >> (inode->i_blkbits - 9));
}
- ext4_put_io_end_defer(io_end);
+ if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
+ ext4_free_io_end(io_end);
+ return;
+ }
+
+ ext4_add_complete_io(io_end);
}
void ext4_io_submit(struct ext4_io_submit *io)
@@ -338,37 +304,40 @@
bio_put(io->io_bio);
}
io->io_bio = NULL;
-}
-
-void ext4_io_submit_init(struct ext4_io_submit *io,
- struct writeback_control *wbc)
-{
- io->io_op = (wbc->sync_mode == WB_SYNC_ALL ? WRITE_SYNC : WRITE);
- io->io_bio = NULL;
+ io->io_op = 0;
io->io_end = NULL;
}
-static int io_submit_init_bio(struct ext4_io_submit *io,
- struct buffer_head *bh)
+static int io_submit_init(struct ext4_io_submit *io,
+ struct inode *inode,
+ struct writeback_control *wbc,
+ struct buffer_head *bh)
{
+ ext4_io_end_t *io_end;
+ struct page *page = bh->b_page;
int nvecs = bio_get_nr_vecs(bh->b_bdev);
struct bio *bio;
+ io_end = ext4_init_io_end(inode, GFP_NOFS);
+ if (!io_end)
+ return -ENOMEM;
bio = bio_alloc(GFP_NOIO, min(nvecs, BIO_MAX_PAGES));
bio->bi_sector = bh->b_blocknr * (bh->b_size >> 9);
bio->bi_bdev = bh->b_bdev;
+ bio->bi_private = io->io_end = io_end;
bio->bi_end_io = ext4_end_bio;
- bio->bi_private = ext4_get_io_end(io->io_end);
- if (!io->io_end->size)
- io->io_end->offset = (bh->b_page->index << PAGE_CACHE_SHIFT)
- + bh_offset(bh);
+
+ io_end->offset = (page->index << PAGE_CACHE_SHIFT) + bh_offset(bh);
+
io->io_bio = bio;
+ io->io_op = (wbc->sync_mode == WB_SYNC_ALL ? WRITE_SYNC : WRITE);
io->io_next_block = bh->b_blocknr;
return 0;
}
static int io_submit_add_bh(struct ext4_io_submit *io,
struct inode *inode,
+ struct writeback_control *wbc,
struct buffer_head *bh)
{
ext4_io_end_t *io_end;
@@ -379,18 +348,18 @@
ext4_io_submit(io);
}
if (io->io_bio == NULL) {
- ret = io_submit_init_bio(io, bh);
+ ret = io_submit_init(io, inode, wbc, bh);
if (ret)
return ret;
}
- ret = bio_add_page(io->io_bio, bh->b_page, bh->b_size, bh_offset(bh));
- if (ret != bh->b_size)
- goto submit_and_retry;
io_end = io->io_end;
if (test_clear_buffer_uninit(bh))
ext4_set_io_unwritten_flag(inode, io_end);
- io_end->size += bh->b_size;
+ io->io_end->size += bh->b_size;
io->io_next_block++;
+ ret = bio_add_page(io->io_bio, bh->b_page, bh->b_size, bh_offset(bh));
+ if (ret != bh->b_size)
+ goto submit_and_retry;
return 0;
}
@@ -462,7 +431,7 @@
do {
if (!buffer_async_write(bh))
continue;
- ret = io_submit_add_bh(io, inode, bh);
+ ret = io_submit_add_bh(io, inode, wbc, bh);
if (ret) {
/*
* We only get here on ENOMEM. Not much else
