diff options
| author | Tejun Heo | 2006-02-20 23:48:38 +0900 |
|---|---|---|
| committer | Jeff Garzik | 2006-02-20 16:48:18 -0500 |
| commit | cc1887f3d8ae8ea61efa1a75af8ec0467b9dd546 (patch) | |
| tree | 3d02d3dfef8803fe9130ebac2172b6271b907109 | |
| parent | 9ae61c6cb69f5251d160576c324948805f97e901 (diff) | |
[PATCH] libata: fix qc->n_elem == 0 case handling in ata_qc_next_sg
This patch makes ata_for_each_sg() start with pad_sgent when
qc->n_elem is zero. Previously, ata_for_each_sg() unconditionally
started with qc->__sg, handling the first sg to fill_sg() routines
even when the entry was invalid. And while at it, unwind ?: in
ata_qc_next_sg() into if statement.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
| -rw-r--r-- | include/linux/libata.h | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/include/linux/libata.h b/include/linux/libata.h index 9e5db2949c58..c91be5e64ede 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -557,17 +557,29 @@ ata_sg_is_last(struct scatterlist *sg, struct ata_queued_cmd *qc) } static inline struct scatterlist * +ata_qc_first_sg(struct ata_queued_cmd *qc) +{ + if (qc->n_elem) + return qc->__sg; + if (qc->pad_len) + return &qc->pad_sgent; + return NULL; +} + +static inline struct scatterlist * ata_qc_next_sg(struct scatterlist *sg, struct ata_queued_cmd *qc) { if (sg == &qc->pad_sgent) return NULL; if (++sg - qc->__sg < qc->n_elem) return sg; - return qc->pad_len ? &qc->pad_sgent : NULL; + if (qc->pad_len) + return &qc->pad_sgent; + return NULL; } #define ata_for_each_sg(sg, qc) \ - for (sg = qc->__sg; sg; sg = ata_qc_next_sg(sg, qc)) + for (sg = ata_qc_first_sg(qc); sg; sg = ata_qc_next_sg(sg, qc)) static inline unsigned int ata_tag_valid(unsigned int tag) { |