libata: implement ata_qc_raw_nbytes()
Implement ata_qc_raw_nbytes() which determines the raw user-requested
size of a PC command.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/include/linux/libata.h b/include/linux/libata.h
index a05f600..269cdba 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -463,6 +463,7 @@
unsigned int sect_size;
unsigned int nbytes;
+ unsigned int extrabytes;
unsigned int curbytes;
struct scatterlist *cursg;
@@ -1336,6 +1337,11 @@
return NULL;
}
+static inline unsigned int ata_qc_raw_nbytes(struct ata_queued_cmd *qc)
+{
+ return qc->nbytes - min(qc->extrabytes, qc->nbytes);
+}
+
static inline void ata_tf_init(struct ata_device *dev, struct ata_taskfile *tf)
{
memset(tf, 0, sizeof(*tf));
@@ -1354,7 +1360,7 @@
qc->flags = 0;
qc->cursg = NULL;
qc->cursg_ofs = 0;
- qc->nbytes = qc->curbytes = 0;
+ qc->nbytes = qc->extrabytes = qc->curbytes = 0;
qc->n_elem = 0;
qc->err_mask = 0;
qc->sect_size = ATA_SECT_SIZE;