Scatter/gather functionality uses the newly added DMA helpers. The
device can choose between doing DMA itself, or calling scsi_req_data
as usual, which will use the newly added DMA helpers to map the
destination area(s) piecewise and copy to/from them.
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
---
hw/esp.c | 2 +-
hw/lsi53c895a.c | 2 +-
hw/scsi-bus.c | 34 +++++++++++++++++++++++++++++++---
hw/scsi.h | 4 +++-
hw/spapr_vscsi.c | 2 +-
hw/usb-msd.c | 2 +-
6 files changed, 38 insertions(+), 8 deletions(-)
diff --git a/hw/esp.c b/hw/esp.c
index 5d29071..2d098ea 100644
--- a/hw/esp.c
+++ b/hw/esp.c
@@ -245,7 +245,7 @@ static void do_busid_cmd(ESPState *s, uint8_t *buf, uint8_t
busid)
DPRINTF("do_busid_cmd: busid 0x%x\n", busid);
lun = busid & 7;
s->current_req = scsi_req_new(s->current_dev, 0, lun, buf, NULL);
- datalen = scsi_req_enqueue(s->current_req);
+ datalen = scsi_req_enqueue(s->current_req, NULL);
s->ti_size = datalen;
if (datalen != 0) {
s->rregs[ESP_RSTAT] = STAT_TC;
diff --git a/hw/lsi53c895a.c b/hw/lsi53c895a.c
index a0c2419..ee7f67c 100644
--- a/hw/lsi53c895a.c
+++ b/hw/lsi53c895a.c
@@ -785,7 +785,7 @@ static void lsi_do_command(LSIState *s)
s->current->req = scsi_req_new(dev, s->current->tag, s->current_lun, buf,
s->current);
- n = scsi_req_enqueue(s->current->req);
+ n = scsi_req_enqueue(s->current->req, NULL);
if (n) {
if (n > 0) {
lsi_set_phase(s, PHASE_DI);
diff --git a/hw/scsi-bus.c b/hw/scsi-bus.c
index b49d02d..5876f78 100644
--- a/hw/scsi-bus.c
+++ b/hw/scsi-bus.c
@@ -5,6 +5,7 @@
#include "qdev.h"
#include "blockdev.h"
#include "trace.h"
+#include "dma.h"
static char *scsibus_get_fw_dev_path(DeviceState *dev);
static int scsi_req_parse(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf);
@@ -521,7 +522,7 @@ void scsi_req_build_sense(SCSIRequest *req, SCSISense sense)
req->sense_len = 18;
}
-int32_t scsi_req_enqueue(SCSIRequest *req)
+int32_t scsi_req_enqueue(SCSIRequest *req, QEMUSGList *sg)
{
int32_t rc;
@@ -529,6 +530,7 @@ int32_t scsi_req_enqueue(SCSIRequest *req)
scsi_req_ref(req);
req->enqueued = true;
QTAILQ_INSERT_TAIL(&req->dev->requests, req, next);
+ req->sg = sg;
scsi_req_ref(req);
rc = req->ops->send_command(req, req->cmd.buf);
@@ -1039,15 +1041,41 @@ void scsi_req_continue(SCSIRequest *req)
}
}
+static void scsi_dma_cb(void *opaque, int ret)
+{
+ SCSIRequest *req = opaque;
+ assert(ret == 0);
+ assert(req->dma_started);
+ req->resid = qemu_sglist_get_resid(req->sg);
+ scsi_req_continue(req);
+}
+
/* Called by the devices when data is ready for the HBA. The HBA should
start a DMA operation to read or fill the device's data buffer.
Once it completes, calling scsi_req_continue will restart I/O. */
void scsi_req_data(SCSIRequest *req, int len)
{
+ uint8_t *buf;
trace_scsi_req_data(req->dev->id, req->lun, req->tag, len);
assert(req->cmd.mode != SCSI_XFER_NONE);
- req->resid -= len;
- req->bus->ops->transfer_data(req, len);
+ if (!req->sg) {
+ req->resid -= len;
+ req->bus->ops->transfer_data(req, len);
+ return;
+ }
+
+ /* If the device calls scsi_req_data and the HBA specified a
+ * scatter/gather list, the transfer has to happen in a single
+ * step. */
+ assert(!req->dma_started);
+ req->dma_started = true;
+
+ buf = scsi_req_get_buf(req);
+ if (req->cmd.mode == SCSI_XFER_FROM_DEV) {
+ req->aiocb = dma_buf_read(buf, len, req->sg, scsi_dma_cb, req);
+ } else {
+ req->aiocb = dma_buf_write(buf, len, req->sg, scsi_dma_cb, req);
+ }
}
void scsi_req_print(SCSIRequest *req)
diff --git a/hw/scsi.h b/hw/scsi.h
index 76d4df2..febb6fd 100644
--- a/hw/scsi.h
+++ b/hw/scsi.h
@@ -50,6 +50,8 @@ struct SCSIRequest {
size_t resid;
SCSICommand cmd;
BlockDriverAIOCB *aiocb;
+ QEMUSGList *sg;
+ bool dma_started;
uint8_t sense[SCSI_SENSE_BUF_SIZE];
uint32_t sense_len;
bool enqueued;
@@ -174,7 +176,7 @@ SCSIRequest *scsi_req_alloc(SCSIReqOps *reqops, SCSIDevice
*d, uint32_t tag,
uint32_t lun, void *hba_private);
SCSIRequest *scsi_req_new(SCSIDevice *d, uint32_t tag, uint32_t lun,
uint8_t *buf, void *hba_private);
-int32_t scsi_req_enqueue(SCSIRequest *req);
+int32_t scsi_req_enqueue(SCSIRequest *req, QEMUSGList *qsg);
void scsi_req_free(SCSIRequest *req);
SCSIRequest *scsi_req_ref(SCSIRequest *req);
void scsi_req_unref(SCSIRequest *req);
diff --git a/hw/spapr_vscsi.c b/hw/spapr_vscsi.c
index 128b5a6..3a6d35f 100644
--- a/hw/spapr_vscsi.c
+++ b/hw/spapr_vscsi.c
@@ -601,7 +601,7 @@ static int vscsi_queue_cmd(VSCSIState *s, vscsi_req *req)
req->lun = lun;
req->sreq = scsi_req_new(sdev, req->qtag, lun, srp->cmd.cdb, req);
- n = scsi_req_enqueue(req->sreq);
+ n = scsi_req_enqueue(req->sreq, NULL);
dprintf("VSCSI: Queued command tag 0x%x CMD 0x%x ID %d LUN %d ret: %d\n",
req->qtag, srp->cmd.cdb[0], id, lun, n);
diff --git a/hw/usb-msd.c b/hw/usb-msd.c
index 8cddf80..167da8a 100644
--- a/hw/usb-msd.c
+++ b/hw/usb-msd.c
@@ -381,7 +381,7 @@ static int usb_msd_handle_data(USBDevice *dev, USBPacket *p)
s->residue = 0;
s->scsi_len = 0;
s->req = scsi_req_new(s->scsi_dev, s->tag, 0, cbw.cmd, NULL);
- scsi_req_enqueue(s->req);
+ scsi_req_enqueue(s->req, NULL);
/* ??? Should check that USB and SCSI data transfer
directions match. */
if (s->mode != USB_MSDM_CSW && s->residue == 0) {
--
1.7.6
