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

[karo-tx-linux.git] / drivers / ata / libata-core.c

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 4972fdf4bd31ae225e5ef11b1ee7b4921f24f3d0..c035b3d041ee1572492d7a17f56323bde0fccacd 100644 (file)
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -4281,7 +4281,7 @@ static const struct ata_blacklist_entry ata_device_blacklist [] = {
  *     The special characters ?, [, -, or *, can be matched using a set, eg. [*]
  *     Behaviour with malformed patterns is undefined, though generally reasonable.
  *
- *     Example patterns:  "SD1?",  "SD1[0-5]",  "*R0",  SD*1?[012]*xx"
+ *     Sample patterns:  "SD1?",  "SD1[0-5]",  "*R0",  "SD*1?[012]*xx"
  *
  *     This function uses one level of recursion per '*' in pattern.
  *     Since it calls _nothing_ else, and has _no_ explicit local variables,
@@ -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);