Signed-off-by: Jens Axboe <[email protected]>
---
fs/block_dev.c | 76 ++++++++++++++++++++++++++++++++++++++++++++++++++--------
1 file changed, 66 insertions(+), 10 deletions(-)
diff --git a/fs/block_dev.c b/fs/block_dev.c
index 2010997fd326..62ca4ce21222 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -176,9 +176,68 @@ static struct inode *bdev_file_inode(struct file *file)
return file->f_mapping->host;
}
+static void blkdev_bio_end_io_async(struct bio *bio)
+{
+ struct kiocb *iocb = bio->bi_private;
+
+ iocb->ki_complete(iocb, bio->bi_error, 0);
+
+ if (bio_op(bio) == REQ_OP_READ)
+ bio_check_pages_dirty(bio);
+ else
+ bio_put(bio);
+}
+
+static ssize_t
+__blkdev_direct_IO_async(struct kiocb *iocb, struct iov_iter *iter,
+ int nr_pages)
+{
+ struct file *file = iocb->ki_filp;
+ struct block_device *bdev = I_BDEV(bdev_file_inode(file));
+ unsigned blkbits = blksize_bits(bdev_logical_block_size(bdev));
+ loff_t pos = iocb->ki_pos;
+ struct bio *bio;
+ ssize_t ret;
+
+ if ((pos | iov_iter_alignment(iter)) & ((1 << blkbits) - 1))
+ return -EINVAL;
+
+ bio = bio_alloc(GFP_KERNEL, nr_pages);
+ if (!bio)
+ return -ENOMEM;
+
+ bio->bi_bdev = bdev;
+ bio->bi_iter.bi_sector = pos >> blkbits;
+ bio->bi_private = iocb;
+ bio->bi_end_io = blkdev_bio_end_io_async;
+
+ ret = bio_iov_iter_get_pages(bio, iter);
+ if (unlikely(ret))
+ return ret;
+
+ /*
+ * Overload bio size in error. If it gets set, we lose the
+ * size, but we don't need the size for that case. IO is limited
+ * to BIO_MAX_PAGES, so we can't overflow.
+ */
+ ret = bio->bi_error = bio->bi_iter.bi_size;
+
+ if (iov_iter_rw(iter) == READ) {
+ bio_set_op_attrs(bio, REQ_OP_READ, 0);
+ bio_set_pages_dirty(bio);
+ } else {
+ bio_set_op_attrs(bio, REQ_OP_WRITE, REQ_SYNC | REQ_IDLE);
+ task_io_account_write(ret);
+ }
+
+ submit_bio(bio);
+ iocb->ki_pos += ret;
+ return -EIOCBQUEUED;
+}
+
#define DIO_INLINE_BIO_VECS 4
-static void blkdev_bio_end_io_simple(struct bio *bio)
+static void blkdev_bio_end_io_sync(struct bio *bio)
{
struct task_struct *waiter = bio->bi_private;
@@ -187,8 +246,7 @@ static void blkdev_bio_end_io_simple(struct bio *bio)
}
static ssize_t
-__blkdev_direct_IO_simple(struct kiocb *iocb, struct iov_iter *iter,
- int nr_pages)
+__blkdev_direct_IO_sync(struct kiocb *iocb, struct iov_iter *iter, int
nr_pages)
{
struct file *file = iocb->ki_filp;
struct block_device *bdev = I_BDEV(bdev_file_inode(file));
@@ -218,7 +276,7 @@ __blkdev_direct_IO_simple(struct kiocb *iocb, struct
iov_iter *iter,
bio.bi_bdev = bdev;
bio.bi_iter.bi_sector = pos >> blkbits;
bio.bi_private = current;
- bio.bi_end_io = blkdev_bio_end_io_simple;
+ bio.bi_end_io = blkdev_bio_end_io_sync;
ret = bio_iov_iter_get_pages(&bio, iter);
if (unlikely(ret))
@@ -263,18 +321,16 @@ __blkdev_direct_IO_simple(struct kiocb *iocb, struct
iov_iter *iter,
static ssize_t
blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
{
- struct file *file = iocb->ki_filp;
- struct inode *inode = bdev_file_inode(file);
int nr_pages;
nr_pages = iov_iter_npages(iter, BIO_MAX_PAGES);
if (!nr_pages)
return 0;
+
if (is_sync_kiocb(iocb))
- return __blkdev_direct_IO_simple(iocb, iter, nr_pages);
- return __blockdev_direct_IO(iocb, inode, I_BDEV(inode), iter,
- blkdev_get_block, NULL, NULL,
- DIO_SKIP_DIO_COUNT);
+ return __blkdev_direct_IO_sync(iocb, iter, nr_pages);
+
+ return __blkdev_direct_IO_async(iocb, iter, nr_pages);
}
int __sync_blockdev(struct block_device *bdev, int wait)
--
2.7.4
--
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