libata: kill qc->nsect and cursect
libata used two separate sets of variables to record request size and
current offset for ATA and ATAPI. This is confusing and fragile.
This patch replaces qc->nsect/cursect with qc->nbytes/curbytes and
kills them. Also, ata_pio_sector() is updated to use bytes for
qc->cursg_ofs instead of sectors. The field used to be used in bytes
for ATAPI and in sectors for ATA.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 89f3cf5..c1444d8 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -1249,7 +1249,6 @@
buflen += sg[i].length;
ata_sg_init(qc, sg, n_elem);
- qc->nsect = buflen / ATA_SECT_SIZE;
qc->nbytes = buflen;
}
@@ -4006,11 +4005,11 @@
unsigned int offset;
unsigned char *buf;
- if (qc->cursect == (qc->nsect - 1))
+ if (qc->curbytes == qc->nbytes - ATA_SECT_SIZE)
ap->hsm_task_state = HSM_ST_LAST;
page = sg[qc->cursg].page;
- offset = sg[qc->cursg].offset + qc->cursg_ofs * ATA_SECT_SIZE;
+ offset = sg[qc->cursg].offset + qc->cursg_ofs;
/* get the current page and offset */
page = nth_page(page, (offset >> PAGE_SHIFT));
@@ -4035,10 +4034,10 @@
ap->ops->data_xfer(qc->dev, buf + offset, ATA_SECT_SIZE, do_write);
}
- qc->cursect++;
- qc->cursg_ofs++;
+ qc->curbytes += ATA_SECT_SIZE;
+ qc->cursg_ofs += ATA_SECT_SIZE;
- if ((qc->cursg_ofs * ATA_SECT_SIZE) == (&sg[qc->cursg])->length) {
+ if (qc->cursg_ofs == (&sg[qc->cursg])->length) {
qc->cursg++;
qc->cursg_ofs = 0;
}
@@ -4063,7 +4062,8 @@
WARN_ON(qc->dev->multi_count == 0);
- nsect = min(qc->nsect - qc->cursect, qc->dev->multi_count);
+ nsect = min((qc->nbytes - qc->curbytes) / ATA_SECT_SIZE,
+ qc->dev->multi_count);
while (nsect--)
ata_pio_sector(qc);
} else