The direct-io.c rewrite to use the iov_iter infrastructure stopped updating
the size field in struct dio_submit, and thus rendered the check for
allowing asynchronous completions to always return false.  Fix this by
comparing it to the count of bytes in the iov_iter instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Tim Chen <tim.c.chen@linux.intel.com>
Tested-by: Tim Chen <tim.c.chen@linux.intel.com>
This commit is contained in:
Christoph Hellwig 2014-07-30 07:18:48 -04:00 коммит произвёл Al Viro
Родитель 6f0928036b
Коммит af43647277
1 изменённых файлов: 4 добавлений и 5 удалений

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@ -71,7 +71,6 @@ struct dio_submit {
been performed at the start of a been performed at the start of a
write */ write */
int pages_in_io; /* approximate total IO pages */ int pages_in_io; /* approximate total IO pages */
size_t size; /* total request size (doesn't change)*/
sector_t block_in_file; /* Current offset into the underlying sector_t block_in_file; /* Current offset into the underlying
file in dio_block units. */ file in dio_block units. */
unsigned blocks_available; /* At block_in_file. changes */ unsigned blocks_available; /* At block_in_file. changes */
@ -1104,7 +1103,8 @@ do_blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode,
unsigned blkbits = i_blkbits; unsigned blkbits = i_blkbits;
unsigned blocksize_mask = (1 << blkbits) - 1; unsigned blocksize_mask = (1 << blkbits) - 1;
ssize_t retval = -EINVAL; ssize_t retval = -EINVAL;
loff_t end = offset + iov_iter_count(iter); size_t count = iov_iter_count(iter);
loff_t end = offset + count;
struct dio *dio; struct dio *dio;
struct dio_submit sdio = { 0, }; struct dio_submit sdio = { 0, };
struct buffer_head map_bh = { 0, }; struct buffer_head map_bh = { 0, };
@ -1287,10 +1287,9 @@ do_blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode,
*/ */
BUG_ON(retval == -EIOCBQUEUED); BUG_ON(retval == -EIOCBQUEUED);
if (dio->is_async && retval == 0 && dio->result && if (dio->is_async && retval == 0 && dio->result &&
((rw == READ) || (dio->result == sdio.size))) (rw == READ || dio->result == count))
retval = -EIOCBQUEUED; retval = -EIOCBQUEUED;
else
if (retval != -EIOCBQUEUED)
dio_await_completion(dio); dio_await_completion(dio);
if (drop_refcount(dio) == 0) { if (drop_refcount(dio) == 0) {