NVMe: Add nvme_setup_prps()
Generalise the code from nvme_identify() that sets PRP1 & PRP2 so that
it's usable for commands sent by nvme_submit_bio_queue().
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
diff --git a/drivers/block/nvme.c b/drivers/block/nvme.c
index c0ef1dd..1e57737 100644
--- a/drivers/block/nvme.c
+++ b/drivers/block/nvme.c
@@ -240,6 +240,36 @@
bio_endio(bio, status ? -EIO : 0);
}
+/* length is in bytes */
+static void nvme_setup_prps(struct nvme_common_command *cmd,
+ struct scatterlist *sg, int length)
+{
+ int dma_len = sg_dma_len(sg);
+ u64 dma_addr = sg_dma_address(sg);
+ int offset = offset_in_page(dma_addr);
+
+ cmd->prp1 = cpu_to_le64(dma_addr);
+ length -= (PAGE_SIZE - offset);
+ if (length <= 0)
+ return;
+
+ dma_len -= (PAGE_SIZE - offset);
+ if (dma_len) {
+ dma_addr += (PAGE_SIZE - offset);
+ } else {
+ sg = sg_next(sg);
+ dma_addr = sg_dma_address(sg);
+ dma_len = sg_dma_len(sg);
+ }
+
+ if (length <= PAGE_SIZE) {
+ cmd->prp2 = cpu_to_le64(dma_addr);
+ return;
+ }
+
+ /* XXX: support PRP lists */
+}
+
static int nvme_map_bio(struct device *dev, struct nvme_req_info *info,
struct bio *bio, enum dma_data_direction dma_dir, int psegs)
{
@@ -261,7 +291,7 @@
static int nvme_submit_bio_queue(struct nvme_queue *nvmeq, struct nvme_ns *ns,
struct bio *bio)
{
- struct nvme_rw_command *cmnd;
+ struct nvme_command *cmnd;
struct nvme_req_info *info;
enum dma_data_direction dma_dir;
int cmdid;
@@ -290,27 +320,26 @@
dsmgmt |= NVME_RW_DSM_FREQ_PREFETCH;
spin_lock_irqsave(&nvmeq->q_lock, flags);
- cmnd = &nvmeq->sq_cmds[nvmeq->sq_tail].rw;
+ cmnd = &nvmeq->sq_cmds[nvmeq->sq_tail];
if (bio_data_dir(bio)) {
- cmnd->opcode = nvme_cmd_write;
+ cmnd->rw.opcode = nvme_cmd_write;
dma_dir = DMA_TO_DEVICE;
} else {
- cmnd->opcode = nvme_cmd_read;
+ cmnd->rw.opcode = nvme_cmd_read;
dma_dir = DMA_FROM_DEVICE;
}
nvme_map_bio(nvmeq->q_dmadev, info, bio, dma_dir, psegs);
- cmnd->flags = 1;
- cmnd->command_id = cmdid;
- cmnd->nsid = cpu_to_le32(ns->ns_id);
- cmnd->prp1 = cpu_to_le64(sg_phys(info->sg));
- /* XXX: Support more than one PRP */
- cmnd->slba = cpu_to_le64(bio->bi_sector >> (ns->lba_shift - 9));
- cmnd->length = cpu_to_le16((bio->bi_size >> ns->lba_shift) - 1);
- cmnd->control = cpu_to_le16(control);
- cmnd->dsmgmt = cpu_to_le32(dsmgmt);
+ cmnd->rw.flags = 1;
+ cmnd->rw.command_id = cmdid;
+ cmnd->rw.nsid = cpu_to_le32(ns->ns_id);
+ nvme_setup_prps(&cmnd->common, info->sg, bio->bi_size);
+ cmnd->rw.slba = cpu_to_le64(bio->bi_sector >> (ns->lba_shift - 9));
+ cmnd->rw.length = cpu_to_le16((bio->bi_size >> ns->lba_shift) - 1);
+ cmnd->rw.control = cpu_to_le16(control);
+ cmnd->rw.dsmgmt = cpu_to_le32(dsmgmt);
writel(nvmeq->sq_tail, nvmeq->q_db);
if (++nvmeq->sq_tail == nvmeq->q_depth)
@@ -667,8 +696,9 @@
goto put_pages;
}
sg_init_table(sg, count);
- for (i = 0; i < count; i++)
- sg_set_page(&sg[i], pages[i], PAGE_SIZE, 0);
+ sg_set_page(&sg[0], pages[0], PAGE_SIZE - offset, offset);
+ if (count > 1)
+ sg_set_page(&sg[1], pages[1], offset, 0);
nents = dma_map_sg(&dev->pci_dev->dev, sg, count, DMA_FROM_DEVICE);
if (!nents)
goto put_pages;
@@ -676,15 +706,7 @@
memset(&c, 0, sizeof(c));
c.identify.opcode = nvme_admin_identify;
c.identify.nsid = cns ? 0 : cpu_to_le32(ns->ns_id);
- c.identify.prp1 = cpu_to_le64(sg_dma_address(&sg[0]) + offset);
- if (count > 1) {
- u64 dma_addr;
- if (nents > 1)
- dma_addr = sg_dma_address(&sg[1]);
- else
- dma_addr = sg_dma_address(&sg[0]) + PAGE_SIZE;
- c.identify.prp2 = cpu_to_le64(dma_addr);
- }
+ nvme_setup_prps(&c.common, sg, 4096);
c.identify.cns = cpu_to_le32(cns);
err = nvme_submit_admin_cmd(dev, &c, NULL);