From 8726021626780a73e795c9b939e1ee49ac8c9136 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Tue, 16 Oct 2007 11:14:12 +0200 Subject: libata: convert to using sg helpers This converts libata to using the sg helpers for looking up sg elements, instead of doing it manually. Signed-off-by: Jens Axboe --- drivers/ata/libata-core.c | 30 ++++++++++++++++-------------- 1 file changed, 16 insertions(+), 14 deletions(-) (limited to 'drivers/ata') diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c index 68699b3e7998..e52c33180e42 100644 --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -1410,7 +1410,7 @@ static void ata_qc_complete_internal(struct ata_queued_cmd *qc) */ unsigned ata_exec_internal_sg(struct ata_device *dev, struct ata_taskfile *tf, const u8 *cdb, - int dma_dir, struct scatterlist *sg, + int dma_dir, struct scatterlist *sgl, unsigned int n_elem, unsigned long timeout) { struct ata_link *link = dev->link; @@ -1472,11 +1472,12 @@ unsigned ata_exec_internal_sg(struct ata_device *dev, qc->dma_dir = dma_dir; if (dma_dir != DMA_NONE) { unsigned int i, buflen = 0; + struct scatterlist *sg; - for (i = 0; i < n_elem; i++) - buflen += sg[i].length; + for_each_sg(sgl, sg, n_elem, i) + buflen += sg->length; - ata_sg_init(qc, sg, n_elem); + ata_sg_init(qc, sgl, n_elem); qc->nbytes = buflen; } @@ -4292,7 +4293,7 @@ void ata_sg_clean(struct ata_queued_cmd *qc) if (qc->n_elem) dma_unmap_sg(ap->dev, sg, qc->n_elem, dir); /* restore last sg */ - sg[qc->orig_n_elem - 1].length += qc->pad_len; + sg_last(sg, qc->orig_n_elem)->length += qc->pad_len; if (pad_buf) { struct scatterlist *psg = &qc->pad_sgent; void *addr = kmap_atomic(psg->page, KM_IRQ0); @@ -4547,6 +4548,7 @@ void ata_sg_init_one(struct ata_queued_cmd *qc, void *buf, unsigned int buflen) qc->orig_n_elem = 1; qc->buf_virt = buf; qc->nbytes = buflen; + qc->cursg = qc->__sg; sg_init_one(&qc->sgent, buf, buflen); } @@ -4572,6 +4574,7 @@ void ata_sg_init(struct ata_queued_cmd *qc, struct scatterlist *sg, qc->__sg = sg; qc->n_elem = n_elem; qc->orig_n_elem = n_elem; + qc->cursg = qc->__sg; } /** @@ -4661,7 +4664,7 @@ static int ata_sg_setup(struct ata_queued_cmd *qc) { struct ata_port *ap = qc->ap; struct scatterlist *sg = qc->__sg; - struct scatterlist *lsg = &sg[qc->n_elem - 1]; + struct scatterlist *lsg = sg_last(qc->__sg, qc->n_elem); int n_elem, pre_n_elem, dir, trim_sg = 0; VPRINTK("ENTER, ata%u\n", ap->print_id); @@ -4825,7 +4828,6 @@ void ata_data_xfer_noirq(struct ata_device *adev, unsigned char *buf, static void ata_pio_sector(struct ata_queued_cmd *qc) { int do_write = (qc->tf.flags & ATA_TFLAG_WRITE); - struct scatterlist *sg = qc->__sg; struct ata_port *ap = qc->ap; struct page *page; unsigned int offset; @@ -4834,8 +4836,8 @@ static void ata_pio_sector(struct ata_queued_cmd *qc) if (qc->curbytes == qc->nbytes - qc->sect_size) ap->hsm_task_state = HSM_ST_LAST; - page = sg[qc->cursg].page; - offset = sg[qc->cursg].offset + qc->cursg_ofs; + page = qc->cursg->page; + offset = qc->cursg->offset + qc->cursg_ofs; /* get the current page and offset */ page = nth_page(page, (offset >> PAGE_SHIFT)); @@ -4863,8 +4865,8 @@ static void ata_pio_sector(struct ata_queued_cmd *qc) qc->curbytes += qc->sect_size; qc->cursg_ofs += qc->sect_size; - if (qc->cursg_ofs == (&sg[qc->cursg])->length) { - qc->cursg++; + if (qc->cursg_ofs == qc->cursg->length) { + qc->cursg = sg_next(qc->cursg); qc->cursg_ofs = 0; } } @@ -4959,7 +4961,7 @@ static void __atapi_pio_bytes(struct ata_queued_cmd *qc, unsigned int bytes) ap->hsm_task_state = HSM_ST_LAST; next_sg: - if (unlikely(qc->cursg >= qc->n_elem)) { + if (unlikely(qc->cursg == sg_last(qc->__sg, qc->n_elem))) { /* * The end of qc->sg is reached and the device expects * more data to transfer. In order not to overrun qc->sg @@ -4982,7 +4984,7 @@ next_sg: return; } - sg = &qc->__sg[qc->cursg]; + sg = qc->cursg; page = sg->page; offset = sg->offset + qc->cursg_ofs; @@ -5021,7 +5023,7 @@ next_sg: qc->cursg_ofs += count; if (qc->cursg_ofs == sg->length) { - qc->cursg++; + qc->cursg = sg_next(qc->cursg); qc->cursg_ofs = 0; } -- cgit 1.4.1 From 0874ee76bcd06e2f53c32a56773ad82f5920f0f9 Mon Sep 17 00:00:00 2001 From: FUJITA Tomonori Date: Sat, 18 Aug 2007 18:27:36 +0900 Subject: libata sg chaining support fix Signed-off-by: FUJITA Tomonori Signed-off-by: Jens Axboe --- drivers/ata/libata-core.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'drivers/ata') diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c index e52c33180e42..bbaa545ea999 100644 --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -4952,16 +4952,18 @@ static void __atapi_pio_bytes(struct ata_queued_cmd *qc, unsigned int bytes) { int do_write = (qc->tf.flags & ATA_TFLAG_WRITE); struct scatterlist *sg = qc->__sg; + struct scatterlist *lsg = sg_last(qc->__sg, qc->n_elem); struct ata_port *ap = qc->ap; struct page *page; unsigned char *buf; unsigned int offset, count; + int no_more_sg = 0; if (qc->curbytes + bytes >= qc->nbytes) ap->hsm_task_state = HSM_ST_LAST; next_sg: - if (unlikely(qc->cursg == sg_last(qc->__sg, qc->n_elem))) { + if (unlikely(no_more_sg)) { /* * The end of qc->sg is reached and the device expects * more data to transfer. In order not to overrun qc->sg @@ -5023,6 +5025,9 @@ next_sg: qc->cursg_ofs += count; if (qc->cursg_ofs == sg->length) { + if (qc->cursg == lsg) + no_more_sg = 1; + qc->cursg = sg_next(qc->cursg); qc->cursg_ofs = 0; } -- cgit 1.4.1 From 8889e3c129780cdbe15fed3c366ba3aa3026684d Mon Sep 17 00:00:00 2001 From: FUJITA Tomonori Date: Tue, 18 Sep 2007 12:16:45 +0200 Subject: remove blk_queue_max_phys_segments in libata LIBATA_MAX_PRD is the maximum number of DMA scatter/gather elements permitted by the HBA's DMA engine. It's properly set to q->max_hw_segments via the sg_tablesize parameter. libata shouldn't call blk_queue_max_phys_segments. Now LIBATA_MAX_PRD is equal to SCSI_MAX_PHYS_SEGMENTS by default (both is 128), so everything is fine. But if they are changed, some code (like the scsi mid layer, sg chaining, etc) might not work properly. (Addition from Jens) The basic issue is that the physical segment setting is purely a driver issue. And since SCSI is managing the sglist, libata has no business changing the setting. All libata should care about is the hw segment setting. Signed-off-by: FUJITA Tomonori Signed-off-by: Jens Axboe --- drivers/ata/libata-scsi.c | 2 -- 1 file changed, 2 deletions(-) (limited to 'drivers/ata') diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c index d63c81ed084f..ba62d534f32b 100644 --- a/drivers/ata/libata-scsi.c +++ b/drivers/ata/libata-scsi.c @@ -801,8 +801,6 @@ int ata_scsi_slave_config(struct scsi_device *sdev) ata_scsi_sdev_config(sdev); - blk_queue_max_phys_segments(sdev->request_queue, LIBATA_MAX_PRD); - sdev->manage_start_stop = 1; if (dev) -- cgit 1.4.1