[patch 31/60] USB: isp1760: urb_dequeue doesnt always find the urbs

From: Greg KH
Date: Tue Jun 09 2009 - 23:41:57 EST


-stable review patch. If anyone has any objections, please let us know.

------------------
From: Warren Free <wfree@xxxxxxxx>

commit 0afb20e00b5053170c85298fed842b32d20b4ea9 upstream.

The option driver (and presumably others) allocates several URBs when it
opens and tries to free them when it closes. The isp1760_urb_dequeue
function gets called, but the packet being dequeued is not necessarily at
the
front of one of the 32 queues. If not, the isp1760_urb_done function doesn't
get called for the URB and the process trying to free it hangs forever on a
wait_queue. This patch does two things. If the URB being dequeued has others
queued behind it, it re-queues them. And it searches the queues looking for
the URB being dequeued rather than just looking at the one at the front of
the queue.

[bigeasy@linutronix] whitespace fixes, reformating

Signed-off-by: Warren Free <wfree@xxxxxxxx>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
drivers/usb/host/isp1760-hcd.c | 24 ++++++++++++++++++++++--
1 file changed, 22 insertions(+), 2 deletions(-)

--- a/drivers/usb/host/isp1760-hcd.c
+++ b/drivers/usb/host/isp1760-hcd.c
@@ -1645,6 +1645,7 @@ static int isp1760_urb_dequeue(struct us
u32 reg_base, or_reg, skip_reg;
unsigned long flags;
struct ptd ptd;
+ packet_enqueue *pe;

switch (usb_pipetype(urb->pipe)) {
case PIPE_ISOCHRONOUS:
@@ -1656,6 +1657,7 @@ static int isp1760_urb_dequeue(struct us
reg_base = INT_REGS_OFFSET;
or_reg = HC_INT_IRQ_MASK_OR_REG;
skip_reg = HC_INT_PTD_SKIPMAP_REG;
+ pe = enqueue_an_INT_packet;
break;

default:
@@ -1663,6 +1665,7 @@ static int isp1760_urb_dequeue(struct us
reg_base = ATL_REGS_OFFSET;
or_reg = HC_ATL_IRQ_MASK_OR_REG;
skip_reg = HC_ATL_PTD_SKIPMAP_REG;
+ pe = enqueue_an_ATL_packet;
break;
}

@@ -1674,6 +1677,7 @@ static int isp1760_urb_dequeue(struct us
u32 skip_map;
u32 or_map;
struct isp1760_qtd *qtd;
+ struct isp1760_qh *qh = ints->qh;

skip_map = isp1760_readl(hcd->regs + skip_reg);
skip_map |= 1 << i;
@@ -1686,8 +1690,7 @@ static int isp1760_urb_dequeue(struct us
priv_write_copy(priv, (u32 *)&ptd, hcd->regs + reg_base
+ i * sizeof(ptd), sizeof(ptd));
qtd = ints->qtd;
-
- clean_up_qtdlist(qtd);
+ qtd = clean_up_qtdlist(qtd);

free_mem(priv, ints->payload);

@@ -1698,7 +1701,24 @@ static int isp1760_urb_dequeue(struct us
ints->payload = 0;

isp1760_urb_done(priv, urb, status);
+ if (qtd)
+ pe(hcd, qh, qtd);
break;
+
+ } else if (ints->qtd) {
+ struct isp1760_qtd *qtd, *prev_qtd = ints->qtd;
+
+ for (qtd = ints->qtd->hw_next; qtd; qtd = qtd->hw_next) {
+ if (qtd->urb == urb) {
+ prev_qtd->hw_next = clean_up_qtdlist(qtd);
+ isp1760_urb_done(priv, urb, status);
+ break;
+ }
+ prev_qtd = qtd;
+ }
+ /* we found the urb before the end of the list */
+ if (qtd)
+ break;
}
ints++;
}


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