> if (iomap->flags & IOMAP_F_NEW)
> need_zeroout = true;
> + else {
Curly braces on both sides of the else, please.
> if (dio->flags & IOMAP_DIO_WRITE) {
> - bio_set_op_attrs(bio, REQ_OP_WRITE, REQ_SYNC | REQ_IDLE);
> + int op_flags = REQ_SYNC | REQ_IDLE;
> +
> + if (use_fua)
> + op_flags |= REQ_FUA;
> + else
> + dio->flags &= ~IOMAP_DIO_WRITE_FUA;
> + bio_set_op_attrs(bio, REQ_OP_WRITE, op_flags);
Please kill the bio_set_op_attrs flags while you are at it and assign
directly to bio->bi_opf:
bio->bi_opf = REQ_OP_WRITE | REQ_SYNC | REQ_IDLE;
if (use_fua)
bio->bi_opf |= REQ_FUA;
else
dio->flags &= ~IOMAP_DIO_WRITE_FUA;
> dio->flags |= IOMAP_DIO_WRITE;
> - if (iocb->ki_flags & IOCB_DSYNC)
> + if (iocb->ki_flags & IOCB_DSYNC) {
> dio->flags |= IOMAP_DIO_WRITE_SYNC;
> + /*
> + * Any non-FUA write will clear this flag, hence we know
> + * before completion whether a cache flush is necessary.
> + */
> + dio->flags |= IOMAP_DIO_WRITE_FUA;
I'd mention that we optimistically try fua first in the comment, and then
go on with what you wrote.
> diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
> index ed63f3b69c12..e853f1748a4b 100644
> --- a/include/linux/blkdev.h
> +++ b/include/linux/blkdev.h
> @@ -800,6 +800,7 @@ static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
> #define blk_queue_quiesced(q) test_bit(QUEUE_FLAG_QUIESCED, &(q)->queue_flags)
> #define blk_queue_preempt_only(q) \
> test_bit(QUEUE_FLAG_PREEMPT_ONLY, &(q)->queue_flags)
> +#define blk_queue_fua(q) test_bit(QUEUE_FLAG_FUA, &(q)->queue_flags)
Separate patch, please.
Otherwise looks good:
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
