I was hoping that was the case and you weren't really serious :-). I've
cut a draft version of this, it's not tested at all though to be
careful... It should do what you want, yes? I'm not too happy with this
one, need a bit more time to ponder.
> Well, it doesn't look like cpqfc, at least.
Well thank god. :)
===== drivers/block/cciss.c 1.63 vs edited =====
--- 1.63/drivers/block/cciss.c Fri Oct 18 12:55:58 2002
+++ edited/drivers/block/cciss.c Fri Oct 25 23:07:21 2002
@@ -1681,6 +1681,28 @@
end_that_request_last(cmd->rq);
}
+struct cciss_map_state {
+ CommandList_struct *command;
+ int data_dir;
+};
+
+static void cciss_map_sg(request_queue_t *q, struct scatterlist *sg, int nseg,
+ void *map_cookie)
+{
+ struct cciss_map_state *s = map_cookie;
+ CommandList_struct *c = s->command;
+ ctlr_info_t *h= q->queuedata;
+ u64bit temp64;
+
+ c->SG[nseg].Len = sg->length;
+ temp64.val = (__u64) pci_map_page(h->pdev, sg->page, sg->offset,
+ sg->length, s->data_dir);
+
+ c->SG[nseg].Addr.lower = temp64.val32.lower;
+ c->SG[nseg].Addr.upper = temp64.val32.upper;
+ c->SG[nseg].Ext = 0; // we are not chaining
+}
+
/*
* Get a request and submit it to the controller.
*/
@@ -1690,10 +1712,8 @@
CommandList_struct *c;
int start_blk, seg;
struct request *creq;
- u64bit temp64;
- struct scatterlist tmp_sg[MAXSGENTRIES];
+ struct cciss_map_state map_state;
drive_info_struct *drv;
- int i, dir;
if (blk_queue_plugged(q))
goto startio;
@@ -1735,24 +1755,16 @@
(int) creq->nr_sectors);
#endif /* CCISS_DEBUG */
- seg = blk_rq_map_sg(q, creq, tmp_sg);
-
/* get the DMA records for the setup */
if (c->Request.Type.Direction == XFER_READ)
- dir = PCI_DMA_FROMDEVICE;
+ map_state.data_dir = PCI_DMA_FROMDEVICE;
else
- dir = PCI_DMA_TODEVICE;
+ map_state.data_dir = PCI_DMA_TODEVICE;
+
+ map_state.command = c;
+
+ seg = blk_rq_map_callback(q, creq, cciss_map_sg, &map_state);
- for (i=0; i<seg; i++)
- {
- c->SG[i].Len = tmp_sg[i].length;
- temp64.val = (__u64) pci_map_page(h->pdev, tmp_sg[i].page,
- tmp_sg[i].offset, tmp_sg[i].length,
- dir);
- c->SG[i].Addr.lower = temp64.val32.lower;
- c->SG[i].Addr.upper = temp64.val32.upper;
- c->SG[i].Ext = 0; // we are not chaining
- }
/* track how many SG entries we are using */
if( seg > h->maxSG)
h->maxSG = seg;
===== drivers/block/ll_rw_blk.c 1.123 vs edited =====
--- 1.123/drivers/block/ll_rw_blk.c Fri Oct 18 19:41:37 2002
+++ edited/drivers/block/ll_rw_blk.c Fri Oct 25 23:00:55 2002
@@ -765,13 +793,11 @@
return 0;
}
-/*
- * map a request to scatterlist, return number of sg entries setup. Caller
- * must make sure sg can hold rq->nr_phys_segments entries
- */
-int blk_rq_map_sg(request_queue_t *q, struct request *rq, struct scatterlist *sg)
+int __blk_rq_map(request_queue_t *q, struct request *rq,
+ struct scatterlist *sglist, map_sg_fn *map, void *map_cookie)
{
struct bio_vec *bvec, *bvprv;
+ struct scatterlist *sg, sgstat;
struct bio *bio;
int nsegs, i, cluster;
@@ -782,6 +808,7 @@
* for each bio in rq
*/
bvprv = NULL;
+ sg = NULL;
rq_for_each_bio(bio, rq) {
/*
* for each segment in bio
@@ -790,7 +817,7 @@
int nbytes = bvec->bv_len;
if (bvprv && cluster) {
- if (sg[nsegs - 1].length + nbytes > q->max_segment_size)
+ if (sg->length + nbytes > q->max_segment_size)
goto new_segment;
if (!BIOVEC_PHYS_MERGEABLE(bvprv, bvec))
@@ -798,13 +825,21 @@
if (!BIOVEC_SEG_BOUNDARY(q, bvprv, bvec))
goto new_segment;
- sg[nsegs - 1].length += nbytes;
+ sg->length += nbytes;
} else {
new_segment:
- memset(&sg[nsegs],0,sizeof(struct scatterlist));
- sg[nsegs].page = bvec->bv_page;
- sg[nsegs].length = nbytes;
- sg[nsegs].offset = bvec->bv_offset;
+ if (sglist) {
+ sg = &sglist[nsegs];
+ sg->page = bvec->bv_page;
+ sg->length = nbytes;
+ sg->offset = bvec->bv_offset;
+ } else {
+ sg = &sgstat;
+ sg->page = bvec->bv_page;
+ sg->length = nbytes;
+ sg->offset = bvec->bv_offset;
+ map(q, sg, nsegs, map_cookie);
+ }
nsegs++;
}
@@ -816,10 +851,27 @@
}
/*
+ * map a request to scatterlist, return number of sg entries setup. Caller
+ * must make sure sg can hold rq->nr_phys_segments entries
+ */
+int blk_rq_map_sg(request_queue_t *q, struct request *rq,struct scatterlist *sg)
+{
+ return __blk_rq_map(q, rq, sg, NULL, NULL);
+}
+
+/*
+ * map a request to scatterlist, calling the map function for each segment
+ */
+int blk_rq_map_callback(request_queue_t *q, struct request *rq, map_sg_fn *map,
+ void *map_cookie)
+{
+ return __blk_rq_map(q, rq, NULL, map, map_cookie);
+}
+
+/*
* the standard queue merge functions, can be overridden with device
* specific ones if so desired
*/
-
static inline int ll_new_mergeable(request_queue_t *q,
struct request *req,
struct bio *bio)
===== include/linux/blkdev.h 1.76 vs edited =====
--- 1.76/include/linux/blkdev.h Fri Oct 18 19:50:43 2002
+++ edited/include/linux/blkdev.h Fri Oct 25 23:06:51 2002
@@ -131,6 +136,8 @@
typedef int (prep_rq_fn) (request_queue_t *, struct request *);
typedef void (unplug_fn) (void *q);
+typedef void (map_sg_fn) (request_queue_t *q, struct scatterlist *,int, void *);
+
struct bio_vec;
typedef int (merge_bvec_fn) (request_queue_t *, struct bio *, struct bio_vec *);
@@ -339,9 +348,11 @@
extern void blk_queue_assign_lock(request_queue_t *, spinlock_t *);
extern void blk_queue_prep_rq(request_queue_t *, prep_rq_fn *pfn);
extern void blk_queue_merge_bvec(request_queue_t *, merge_bvec_fn *);
+extern void blk_queue_dma_alignment(request_queue_t *, int);
extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
extern int blk_rq_map_sg(request_queue_t *, struct request *, struct scatterlist *);
+extern int blk_rq_map_callback(request_queue_t *, struct request *, map_sg_fn *, void *);
extern void blk_dump_rq_flags(struct request *, char *);
extern void generic_unplug_device(void *);
extern long nr_blockdev_pages(void);
-- Jens Axboe- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/