libata: be less of a drama queen on empty data commands

ata_qc_issue() BUG_ON()s on data commands w/o data, which may be
submitted via SG_IO.  Be less of a drama queen and just trigger
WARN_ON_ONCE() and fail the command with AC_ERR_SYSTEM.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Stefan Hübner <stefan.huebner@stud.tu-ilmenau.de>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
This commit is contained in:
Tejun Heo 2010-08-23 11:27:27 +02:00 committed by Jeff Garzik
parent d26377b839
commit 60f5d6ef6b

View File

@ -5111,15 +5111,18 @@ void ata_qc_issue(struct ata_queued_cmd *qc)
qc->flags |= ATA_QCFLAG_ACTIVE;
ap->qc_active |= 1 << qc->tag;
/* We guarantee to LLDs that they will have at least one
/*
* We guarantee to LLDs that they will have at least one
* non-zero sg if the command is a data command.
*/
BUG_ON(ata_is_data(prot) && (!qc->sg || !qc->n_elem || !qc->nbytes));
if (WARN_ON_ONCE(ata_is_data(prot) &&
(!qc->sg || !qc->n_elem || !qc->nbytes)))
goto sys_err;
if (ata_is_dma(prot) || (ata_is_pio(prot) &&
(ap->flags & ATA_FLAG_PIO_DMA)))
if (ata_sg_setup(qc))
goto sg_err;
goto sys_err;
/* if device is sleeping, schedule reset and abort the link */
if (unlikely(qc->dev->flags & ATA_DFLAG_SLEEPING)) {
@ -5136,7 +5139,7 @@ void ata_qc_issue(struct ata_queued_cmd *qc)
goto err;
return;
sg_err:
sys_err:
qc->err_mask |= AC_ERR_SYSTEM;
err:
ata_qc_complete(qc);