ext4: move aio completion after unwritten extent conversion
This patch is to be applied upon Christoph's "direct-io: move aio_complete
into ->end_io" patch. It adds iocb and result fields to struct ext4_io_end_t,
so that we can call aio_complete from ext4_end_io_nolock() after the extent
conversion has finished.
I have verified with Christoph's aio-dio test that used to fail after a few
runs on an original kernel but now succeeds on the patched kernel.
See http://thread.gmane.org/gmane.comp.file-systems.ext4/19659 for details.
Signed-off-by: Jiaying Zhang <jiayingz@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 4c7d472..fbb3947 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -170,13 +170,15 @@
};
#define EXT4_IO_UNWRITTEN 0x1
typedef struct ext4_io_end {
- struct list_head list; /* per-file finished AIO list */
+ struct list_head list; /* per-file finished IO list */
struct inode *inode; /* file being written to */
unsigned int flag; /* unwritten or not */
struct page *page; /* page struct for buffer write */
loff_t offset; /* offset in the file */
ssize_t size; /* size of the extent */
struct work_struct work; /* data work queue */
+ struct kiocb *iocb; /* iocb struct for AIO */
+ int result; /* error value for AIO */
} ext4_io_end_t;
/*
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 609159e..46d2079 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -3668,6 +3668,8 @@
return ret;
}
+ if (io->iocb)
+ aio_complete(io->iocb, io->result, 0);
/* clear the DIO AIO unwritten flag */
io->flag = 0;
return ret;
@@ -3767,6 +3769,8 @@
io->offset = 0;
io->size = 0;
io->page = NULL;
+ io->iocb = NULL;
+ io->result = 0;
INIT_WORK(&io->work, ext4_end_io_work);
INIT_LIST_HEAD(&io->list);
}
@@ -3796,12 +3800,18 @@
if (io_end->flag != EXT4_IO_UNWRITTEN){
ext4_free_io_end(io_end);
iocb->private = NULL;
- goto out;
+out:
+ if (is_async)
+ aio_complete(iocb, ret, 0);
+ return;
}
io_end->offset = offset;
io_end->size = size;
- io_end->flag = EXT4_IO_UNWRITTEN;
+ if (is_async) {
+ io_end->iocb = iocb;
+ io_end->result = ret;
+ }
wq = EXT4_SB(io_end->inode->i_sb)->dio_unwritten_wq;
/* queue the work to convert unwritten extents to written */
@@ -3813,9 +3823,6 @@
list_add_tail(&io_end->list, &ei->i_completed_io_list);
spin_unlock_irqrestore(&ei->i_completed_io_lock, flags);
iocb->private = NULL;
-out:
- if (is_async)
- aio_complete(iocb, ret, 0);
}
static void ext4_end_io_buffer_write(struct buffer_head *bh, int uptodate)