aboutsummaryrefslogtreecommitdiff
path: root/fs/ext4/page-io.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/ext4/page-io.c')
-rw-r--r--fs/ext4/page-io.c78
1 files changed, 37 insertions, 41 deletions
diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
index 92f38ee13f8..7e106c810c6 100644
--- a/fs/ext4/page-io.c
+++ b/fs/ext4/page-io.c
@@ -70,7 +70,6 @@ static void put_io_page(struct ext4_io_page *io_page)
void ext4_free_io_end(ext4_io_end_t *io)
{
int i;
- wait_queue_head_t *wq;
BUG_ON(!io);
if (io->page)
@@ -78,56 +77,43 @@ void ext4_free_io_end(ext4_io_end_t *io)
for (i = 0; i < io->num_io_pages; i++)
put_io_page(io->pages[i]);
io->num_io_pages = 0;
- wq = ext4_ioend_wq(io->inode);
- if (atomic_dec_and_test(&EXT4_I(io->inode)->i_ioend_count) &&
- waitqueue_active(wq))
- wake_up_all(wq);
+ 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.
+ *
+ * Called with inode->i_mutex; we depend on this when we manipulate
+ * io->flag, since we could otherwise race with ext4_flush_completed_IO()
*/
int ext4_end_io_nolock(ext4_io_end_t *io)
{
struct inode *inode = io->inode;
loff_t offset = io->offset;
ssize_t size = io->size;
- wait_queue_head_t *wq;
int ret = 0;
ext4_debug("ext4_end_io_nolock: io 0x%p from inode %lu,list->next 0x%p,"
"list->prev 0x%p\n",
io, inode->i_ino, io->list.next, io->list.prev);
- if (list_empty(&io->list))
- return ret;
-
- if (!(io->flag & EXT4_IO_END_UNWRITTEN))
- return ret;
-
ret = ext4_convert_unwritten_extents(inode, offset, size);
if (ret < 0) {
- printk(KERN_EMERG "%s: failed to convert unwritten "
- "extents to written extents, error is %d "
- "io is still on inode %lu aio dio list\n",
- __func__, ret, inode->i_ino);
- return ret;
+ ext4_msg(inode->i_sb, KERN_EMERG,
+ "failed to convert unwritten extents to written "
+ "extents -- potential data loss! "
+ "(inode %lu, offset %llu, size %zd, error %d)",
+ inode->i_ino, offset, size, ret);
}
if (io->iocb)
aio_complete(io->iocb, io->result, 0);
- /* clear the DIO AIO unwritten flag */
- if (io->flag & EXT4_IO_END_UNWRITTEN) {
- io->flag &= ~EXT4_IO_END_UNWRITTEN;
- /* Wake up anyone waiting on unwritten extent conversion */
- wq = ext4_ioend_wq(io->inode);
- if (atomic_dec_and_test(&EXT4_I(inode)->i_aiodio_unwritten) &&
- waitqueue_active(wq)) {
- wake_up_all(wq);
- }
- }
+ /* Wake up anyone waiting on unwritten extent conversion */
+ if (atomic_dec_and_test(&EXT4_I(inode)->i_aiodio_unwritten))
+ wake_up_all(ext4_ioend_wq(io->inode));
return ret;
}
@@ -140,9 +126,15 @@ static void ext4_end_io_work(struct work_struct *work)
struct inode *inode = io->inode;
struct ext4_inode_info *ei = EXT4_I(inode);
unsigned long flags;
- int ret;
+
+ spin_lock_irqsave(&ei->i_completed_io_lock, flags);
+ if (list_empty(&io->list)) {
+ spin_unlock_irqrestore(&ei->i_completed_io_lock, flags);
+ goto free;
+ }
if (!mutex_trylock(&inode->i_mutex)) {
+ spin_unlock_irqrestore(&ei->i_completed_io_lock, flags);
/*
* Requeue the work instead of waiting so that the work
* items queued after this can be processed.
@@ -159,17 +151,11 @@ static void ext4_end_io_work(struct work_struct *work)
io->flag |= EXT4_IO_END_QUEUED;
return;
}
- ret = ext4_end_io_nolock(io);
- if (ret < 0) {
- mutex_unlock(&inode->i_mutex);
- return;
- }
-
- spin_lock_irqsave(&ei->i_completed_io_lock, flags);
- if (!list_empty(&io->list))
- list_del_init(&io->list);
+ list_del_init(&io->list);
spin_unlock_irqrestore(&ei->i_completed_io_lock, flags);
+ (void) ext4_end_io_nolock(io);
mutex_unlock(&inode->i_mutex);
+free:
ext4_free_io_end(io);
}
@@ -350,10 +336,8 @@ submit_and_retry:
if ((io_end->num_io_pages >= MAX_IO_PAGES) &&
(io_end->pages[io_end->num_io_pages-1] != io_page))
goto submit_and_retry;
- if (buffer_uninit(bh) && !(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
- io_end->flag |= EXT4_IO_END_UNWRITTEN;
- atomic_inc(&EXT4_I(inode)->i_aiodio_unwritten);
- }
+ if (buffer_uninit(bh))
+ ext4_set_io_unwritten_flag(inode, io_end);
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));
@@ -401,6 +385,18 @@ int ext4_bio_write_page(struct ext4_io_submit *io,
block_end = block_start + blocksize;
if (block_start >= len) {
+ /*
+ * Comments copied from block_write_full_page_endio:
+ *
+ * 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."
+ */
+ zero_user_segment(page, block_start, block_end);
clear_buffer_dirty(bh);
set_buffer_uptodate(bh);
continue;