[34-longterm 126/247] staging: usbip: vhci: give back URBs from in-flight unlink requests

Paul Gortmaker
2011-06-23T18:10:35Z

From: Max Vozeler <max@vozeler.com>

-------------------
This is a commit scheduled for the next v2.6.34 longterm release.
If you see a problem with using this for longterm, please comment.
-------------------

commit b92a5e23737172c52656a090977408a80d7f06d1 upstream.

If we never received a RET_UNLINK because the TCP
connection broke the pending URBs still need to be
unlinked and given back.

Previously processes would be stuck trying to kill
the URB even after the device was detached.

Signed-off-by: Max Vozeler <max@vozeler.com>
Tested-by: Mark Wehby <MWehby@luxotticaRetail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
---
drivers/staging/usbip/vhci.h | 3 +++
drivers/staging/usbip/vhci_hcd.c | 24 +++++++++++++++++++++++-
drivers/staging/usbip/vhci_rx.c | 15 +++++++++------
3 files changed, 35 insertions(+), 7 deletions(-)

diff --git a/drivers/staging/usbip/vhci.h b/drivers/staging/usbip/vhci.h
index 5e37517..ad3a19d 100644
--- a/drivers/staging/usbip/vhci.h
+++ b/drivers/staging/usbip/vhci.h
@@ -119,6 +119,9 @@ void rh_port_disconnect(int rhport);
void vhci_rx_loop(struct usbip_task *ut);
void vhci_tx_loop(struct usbip_task *ut);

+struct urb *pickup_urb_and_free_priv(struct vhci_device *vdev,
+ __u32 seqnum);
+
#define hardware (&the_controller->pdev.dev)

static inline struct vhci_device *port_to_vdev(__u32 port)
diff --git a/drivers/staging/usbip/vhci_hcd.c b/drivers/staging/usbip/vhci_hcd.c
index b007205..9878e5d 100644
--- a/drivers/staging/usbip/vhci_hcd.c
+++ b/drivers/staging/usbip/vhci_hcd.c
@@ -808,7 +808,6 @@ static int vhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
return 0;
}

-
static void vhci_device_unlink_cleanup(struct vhci_device *vdev)
{
struct vhci_unlink *unlink, *tmp;
@@ -816,11 +815,34 @@ static void vhci_device_unlink_cleanup(struct vhci_device *vdev)
spin_lock(&vdev->priv_lock);

list_for_each_entry_safe(unlink, tmp, &vdev->unlink_tx, list) {
+ usbip_uinfo("unlink cleanup tx %lu\n", unlink->unlink_seqnum);
list_del(&unlink->list);
kfree(unlink);
}

list_for_each_entry_safe(unlink, tmp, &vdev->unlink_rx, list) {
+ struct urb *urb;
+
+ /* give back URB of unanswered unlink request */
+ usbip_uinfo("unlink cleanup rx %lu\n", unlink->unlink_seqnum);
+
+ urb = pickup_urb_and_free_priv(vdev, unlink->unlink_seqnum);
+ if (!urb) {
+ usbip_uinfo("the urb (seqnum %lu) was already given back\n",
+ unlink->unlink_seqnum);
+ list_del(&unlink->list);
+ kfree(unlink);
+ continue;
+ }
+
+ urb->status = -ENODEV;
+
+ spin_lock(&the_controller->lock);
+ usb_hcd_unlink_urb_from_ep(vhci_to_hcd(the_controller), urb);
+ spin_unlock(&the_controller->lock);
+
+ usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb, urb->status);
+
list_del(&unlink->list);
kfree(unlink);
}
diff --git a/drivers/staging/usbip/vhci_rx.c b/drivers/staging/usbip/vhci_rx.c
index 8147d72..bdbedd2 100644
--- a/drivers/staging/usbip/vhci_rx.c
+++ b/drivers/staging/usbip/vhci_rx.c
@@ -23,16 +23,14 @@
#include "vhci.h"

-/* get URB from transmitted urb queue */
-static struct urb *pickup_urb_and_free_priv(struct vhci_device *vdev,
+/* get URB from transmitted urb queue. caller must hold vdev->priv_lock */
+struct urb *pickup_urb_and_free_priv(struct vhci_device *vdev,
__u32 seqnum)
{
struct vhci_priv *priv, *tmp;
struct urb *urb = NULL;
int status;

- spin_lock(&vdev->priv_lock);
-
list_for_each_entry_safe(priv, tmp, &vdev->priv_rx, list) {
if (priv->seqnum == seqnum) {
urb = priv->urb;
@@ -63,8 +61,6 @@ static struct urb *pickup_urb_and_free_priv(struct vhci_device *vdev,
}
}

- spin_unlock(&vdev->priv_lock);
-
return urb;
}

@@ -74,9 +70,11 @@ static void vhci_recv_ret_submit(struct vhci_device *vdev,
struct usbip_device *ud = &vdev->ud;
struct urb *urb;

+ spin_lock(&vdev->priv_lock);

urb = pickup_urb_and_free_priv(vdev, pdu->base.seqnum);

+ spin_unlock(&vdev->priv_lock);

if (!urb) {
usbip_uerr("cannot find a urb of seqnum %u\n",
@@ -161,7 +159,12 @@ static void vhci_recv_ret_unlink(struct vhci_device *vdev,
return;
}

+ spin_lock(&vdev->priv_lock);
+
urb = pickup_urb_and_free_priv(vdev, unlink->unlink_seqnum);
+
+ spin_unlock(&vdev->priv_lock);
+
if (!urb) {
/*
* I get the result of a unlink request. But, it seems that I
--
1.7.4.4