struct iomap_dio *
__iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter,
const struct iomap_ops *ops, const struct iomap_dio_ops *dops,
- bool wait_for_completion)
+ unsigned int dio_flags)
{
struct address_space *mapping = iocb->ki_filp->f_mapping;
struct inode *inode = file_inode(iocb->ki_filp);
size_t count = iov_iter_count(iter);
loff_t pos = iocb->ki_pos;
loff_t end = iocb->ki_pos + count - 1, ret = 0;
- unsigned int flags = IOMAP_DIRECT;
+ bool wait_for_completion =
+ is_sync_kiocb(iocb) || (dio_flags & IOMAP_DIO_FORCE_WAIT);
+ unsigned int iomap_flags = IOMAP_DIRECT;
struct blk_plug plug;
struct iomap_dio *dio;
if (!count)
return NULL;
- if (WARN_ON(is_sync_kiocb(iocb) && !wait_for_completion))
- return ERR_PTR(-EIO);
-
dio = kmalloc(sizeof(*dio), GFP_KERNEL);
if (!dio)
return ERR_PTR(-ENOMEM);
if (iter_is_iovec(iter))
dio->flags |= IOMAP_DIO_DIRTY;
} else {
- flags |= IOMAP_WRITE;
+ iomap_flags |= IOMAP_WRITE;
dio->flags |= IOMAP_DIO_WRITE;
/* for data sync or sync, we need sync completion processing */
ret = -EAGAIN;
goto out_free_dio;
}
- flags |= IOMAP_NOWAIT;
+ iomap_flags |= IOMAP_NOWAIT;
+ }
+
+ if (dio_flags & IOMAP_DIO_OVERWRITE_ONLY) {
+ ret = -EAGAIN;
+ if (pos >= dio->i_size || pos + count > dio->i_size)
+ goto out_free_dio;
+ iomap_flags |= IOMAP_OVERWRITE_ONLY;
}
ret = filemap_write_and_wait_range(mapping, pos, end);
blk_start_plug(&plug);
do {
- ret = iomap_apply(inode, pos, count, flags, ops, dio,
+ ret = iomap_apply(inode, pos, count, iomap_flags, ops, dio,
iomap_dio_actor);
if (ret <= 0) {
/* magic error code to fall back to buffered I/O */
ssize_t
iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter,
const struct iomap_ops *ops, const struct iomap_dio_ops *dops,
- bool wait_for_completion)
+ unsigned int dio_flags)
{
struct iomap_dio *dio;
- dio = __iomap_dio_rw(iocb, iter, ops, dops, wait_for_completion);
+ dio = __iomap_dio_rw(iocb, iter, ops, dops, dio_flags);
if (IS_ERR_OR_NULL(dio))
return PTR_ERR_OR_ZERO(dio);
return iomap_dio_complete(dio);