[PATCH v2 5/5] usb/ohci: Don't use packet from OHCIState for isochronous transfers

From: BALATON Zoltan <balaton@eik.bme.hu>
To: qemu-devel@nongnu.org
Cc: Gerd Hoffmann <kraxel@redhat.com>
Subject: [PATCH v2 5/5] usb/ohci: Don't use packet from OHCIState for isochronous transfers
Date: Tue, 25 Jan 2022 14:33:20 +0100	[thread overview]
Message-ID: <bf523d40f8088a84383cb00ffd2e6e82fa47790d.1643117600.git.balaton@eik.bme.hu> (raw)
In-Reply-To: <cover.1643117600.git.balaton@eik.bme.hu>

Since isochronous transfers cannot be handled async (the function
returns error in that case) we don't need to remember the packet.
Avoid using the usb_packet field in OHCIState (as that can be a
waiting async packet on another endpoint) and allocate and use a local
USBPacket for the iso transfer instead. After this we don't have to
care if we're called from a completion callback or not so we can drop
that parameter as well.

Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
---
 hw/usb/hcd-ohci.c | 71 +++++++++++++++++++++++++----------------------
 1 file changed, 38 insertions(+), 33 deletions(-)

diff --git a/hw/usb/hcd-ohci.c b/hw/usb/hcd-ohci.c
index 09d07367cc..895b29fb86 100644
--- a/hw/usb/hcd-ohci.c
+++ b/hw/usb/hcd-ohci.c
@@ -548,8 +548,7 @@ static int ohci_copy_iso_td(OHCIState *ohci,
 
 #define USUB(a, b) ((int16_t)((uint16_t)(a) - (uint16_t)(b)))
 
-static int ohci_service_iso_td(OHCIState *ohci, struct ohci_ed *ed,
-                               int completion)
+static int ohci_service_iso_td(OHCIState *ohci, struct ohci_ed *ed)
 {
     int dir;
     size_t len = 0;
@@ -559,6 +558,9 @@ static int ohci_service_iso_td(OHCIState *ohci, struct ohci_ed *ed,
     int i;
     USBDevice *dev;
     USBEndpoint *ep;
+    USBPacket *pkt;
+    uint8_t buf[8192];
+    bool int_req;
     struct ohci_iso_td iso_td;
     uint32_t addr;
     uint16_t starting_frame;
@@ -693,40 +695,42 @@ static int ohci_service_iso_td(OHCIState *ohci, struct ohci_ed *ed,
     } else {
         len = end_addr - start_addr + 1;
     }
-    if (len > sizeof(ohci->usb_buf)) {
-        len = sizeof(ohci->usb_buf);
+    if (len > sizeof(buf)) {
+        len = sizeof(buf);
     }
 
     if (len && dir != OHCI_TD_DIR_IN) {
-        if (ohci_copy_iso_td(ohci, start_addr, end_addr, ohci->usb_buf, len,
+        if (ohci_copy_iso_td(ohci, start_addr, end_addr, buf, len,
                              DMA_DIRECTION_TO_DEVICE)) {
             ohci_die(ohci);
             return 1;
         }
     }
 
-    if (!completion) {
-        bool int_req = relative_frame_number == frame_count &&
-                       OHCI_BM(iso_td.flags, TD_DI) == 0;
-        dev = ohci_find_device(ohci, OHCI_BM(ed->flags, ED_FA));
-        if (dev == NULL) {
-            trace_usb_ohci_td_dev_error();
-            return 1;
-        }
-        ep = usb_ep_get(dev, pid, OHCI_BM(ed->flags, ED_EN));
-        usb_packet_setup(&ohci->usb_packet, pid, ep, 0, addr, false, int_req);
-        usb_packet_addbuf(&ohci->usb_packet, ohci->usb_buf, len);
-        usb_handle_packet(dev, &ohci->usb_packet);
-        if (ohci->usb_packet.status == USB_RET_ASYNC) {
-            usb_device_flush_ep_queue(dev, ep);
-            return 1;
-        }
+    dev = ohci_find_device(ohci, OHCI_BM(ed->flags, ED_FA));
+    if (dev == NULL) {
+        trace_usb_ohci_td_dev_error();
+        return 1;
     }
-    if (ohci->usb_packet.status == USB_RET_SUCCESS) {
-        ret = ohci->usb_packet.actual_length;
+    ep = usb_ep_get(dev, pid, OHCI_BM(ed->flags, ED_EN));
+    pkt = g_new0(USBPacket, 1);
+    usb_packet_init(pkt);
+    int_req = relative_frame_number == frame_count &&
+              OHCI_BM(iso_td.flags, TD_DI) == 0;
+    usb_packet_setup(pkt, pid, ep, 0, addr, false, int_req);
+    usb_packet_addbuf(pkt, buf, len);
+    usb_handle_packet(dev, pkt);
+    if (pkt->status == USB_RET_ASYNC) {
+        usb_device_flush_ep_queue(dev, ep);
+        g_free(pkt);
+        return 1;
+    }
+    if (pkt->status == USB_RET_SUCCESS) {
+        ret = pkt->actual_length;
     } else {
-        ret = ohci->usb_packet.status;
+        ret = pkt->status;
     }
+    g_free(pkt);
 
     trace_usb_ohci_iso_td_so(start_offset, end_offset, start_addr, end_addr,
                              str, len, ret);
@@ -734,7 +738,7 @@ static int ohci_service_iso_td(OHCIState *ohci, struct ohci_ed *ed,
     /* Writeback */
     if (dir == OHCI_TD_DIR_IN && ret >= 0 && ret <= len) {
         /* IN transfer succeeded */
-        if (ohci_copy_iso_td(ohci, start_addr, end_addr, ohci->usb_buf, ret,
+        if (ohci_copy_iso_td(ohci, start_addr, end_addr, buf, ret,
                              DMA_DIRECTION_FROM_DEVICE)) {
             ohci_die(ohci);
             return 1;
@@ -1057,7 +1061,7 @@ exit_no_retire:
 }
 
 /* Service an endpoint list.  Returns nonzero if active TD were found.  */
-static int ohci_service_ed_list(OHCIState *ohci, uint32_t head, int completion)
+static int ohci_service_ed_list(OHCIState *ohci, uint32_t head)
 {
     struct ohci_ed ed;
     uint32_t next_ed;
@@ -1108,8 +1112,9 @@ static int ohci_service_ed_list(OHCIState *ohci, uint32_t head, int completion)
                     break;
             } else {
                 /* Handle isochronous endpoints */
-                if (ohci_service_iso_td(ohci, &ed, completion))
+                if (ohci_service_iso_td(ohci, &ed)) {
                     break;
+                }
             }
         }
 
@@ -1136,20 +1141,20 @@ static void ohci_sof(OHCIState *ohci)
 }
 
 /* Process Control and Bulk lists.  */
-static void ohci_process_lists(OHCIState *ohci, int completion)
+static void ohci_process_lists(OHCIState *ohci)
 {
     if ((ohci->ctl & OHCI_CTL_CLE) && (ohci->status & OHCI_STATUS_CLF)) {
         if (ohci->ctrl_cur && ohci->ctrl_cur != ohci->ctrl_head) {
             trace_usb_ohci_process_lists(ohci->ctrl_head, ohci->ctrl_cur);
         }
-        if (!ohci_service_ed_list(ohci, ohci->ctrl_head, completion)) {
+        if (!ohci_service_ed_list(ohci, ohci->ctrl_head)) {
             ohci->ctrl_cur = 0;
             ohci->status &= ~OHCI_STATUS_CLF;
         }
     }
 
     if ((ohci->ctl & OHCI_CTL_BLE) && (ohci->status & OHCI_STATUS_BLF)) {
-        if (!ohci_service_ed_list(ohci, ohci->bulk_head, completion)) {
+        if (!ohci_service_ed_list(ohci, ohci->bulk_head)) {
             ohci->bulk_cur = 0;
             ohci->status &= ~OHCI_STATUS_BLF;
         }
@@ -1173,7 +1178,7 @@ static void ohci_frame_boundary(void *opaque)
         int n;
 
         n = ohci->frame_number & 0x1f;
-        ohci_service_ed_list(ohci, le32_to_cpu(hcca.intr[n]), 0);
+        ohci_service_ed_list(ohci, le32_to_cpu(hcca.intr[n]));
     }
 
     /* Cancel all pending packets if either of the lists has been disabled.  */
@@ -1181,7 +1186,7 @@ static void ohci_frame_boundary(void *opaque)
         ohci_stop_endpoints(ohci);
     }
     ohci->old_ctl = ohci->ctl;
-    ohci_process_lists(ohci, 0);
+    ohci_process_lists(ohci);
 
     /* Stop if UnrecoverableError happened or ohci_sof will crash */
     if (ohci->intr_status & OHCI_INTR_UE) {
@@ -1794,7 +1799,7 @@ static void ohci_async_complete_packet(USBPort *port, USBPacket *packet)
 
     trace_usb_ohci_async_complete();
     ohci->async_complete = true;
-    ohci_process_lists(ohci, 1);
+    ohci_process_lists(ohci);
 }
 
 static USBPortOps ohci_port_ops = {
-- 
2.30.2


