Commit Graph

463 Commits

Author SHA1 Message Date
Jeffy Chen d1aad52cf8 xhci: Cleanup current_cmd in xhci_cleanup_command_queue()
KASAN reported use-after-free bug when xhci host controller died:
[  176.952537] BUG: KASAN: use-after-free in xhci_handle_command_timeout+0x68/0x224
[  176.960846] Write of size 4 at addr ffffffc0cbb01608 by task kworker/3:3/1680
...
[  177.180644] Freed by task 0:
[  177.183882]  kasan_slab_free+0x90/0x15c
[  177.188194]  kfree+0x114/0x28c
[  177.191630]  xhci_cleanup_command_queue+0xc8/0xf8
[  177.196916]  xhci_hc_died+0x84/0x358

Problem here is that when the cmd_timer fired, it would try to access
current_cmd while the command queue is already freed by xhci_hc_died().

Cleanup current_cmd in xhci_cleanup_command_queue() to avoid that.

Fixes: d9f11ba9f1 ("xhci: Rework how we handle unresponsive or hoptlug removed hosts")
Cc: <stable@vger.kernel.org> # v4.12+
Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-17 10:38:12 +02:00
Adam Wallis 49d5b05e19 xhci: allow TRACE to work with EVENT ring dequeue
inc_deq() currently bails earlier for EVENT rings than the common return
point of the function, due to the fact that EVENT rings do not have
link TRBs. The unfortunate side effect of this is that the very useful
trace_xhci_inc_deq() function is not called/usable for EVENT ring
debug.

This patch provides a refactor by removing the multiple return exit
points into a single return which additionally allows for all rings to
use the trace function.

Signed-off-by: Adam Wallis <awallis@codeaurora.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-05 11:01:58 +02:00
Anshuman Gupta 0914ea66d2 usb: xhci: reduce device initiated resume time variance.
This patch will improve the variable auto-resume latency of an usb-port.

The attempt to sync the start of root hub polling with resume time
signaling finish was ruined by a later request to start immediate
root hub polling.

When xhci gets a port status change event interrupt due to PORT_PLC
(port link state transition), linux Host controller driver drives the
resume signalling on the bus for the amount of time defined by
USB_REUME_TIMEOUT(40ms) macro.

This 40ms delay for resume signalling is in acceptable limit, but
it get worse when xhci goes for polling mode in order to detect other
events on its ports and modify rh_timer timer with a variable time out of
1ms to (HZ/4)ms.

drivers/usb/core/hcd.c line 799
mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4)).

Due to above variable timeout usb auto-resume latency varies from
40ms to ~300ms.

Log Snippet:
~128ms latency
[   53.112049] hub 1-0:1.0: state 7 ports 12 chg 0000 evt 0000
[   53.229200] hub 1-0:1.0: state 7 ports 12 chg 0000 evt 0004
[   53.240177] usb 1-2: usb wakeup-resume
[   53.240195] usb 1-2: finish resume
[   53.240357] usb usb1-port2: resume, status 0
-----------------------------------------------------------------
~300ms latency
[   59.946620] hub 1-0:1.0: state 7 ports 12 chg 0000 evt 0000
[   59.979341] hub 1-0:1.0: state 7 ports 12 chg 0000 evt 0000
[   60.229342] hub 1-0:1.0: state 7 ports 12 chg 0000 evt 0004
[   60.251321] usb 1-2: usb wakeup-resume
[   60.251335] usb 1-2: finish resume
[   60.251539] usb usb1-port2: resume, status 0

This variable resume latency can be optimized, as in case of PORT_PLC
change event rh_timer has already been modified with USB_RESUME_TIMEOUT
(40ms) delay,leaving the rest to GetPortStatus and started polling for
root hub status (invoking usb_hcd_poll_rh_status).
We can avoid polling as we have already modified rh_timer with
delay of 40ms.

This patch set the HCD_FLAG_POLL_RH to hcd->flags after modification of
rh_timer, and avoids polling of root hub status. so rh_timer can fire
after 40ms and usb device auto-resuem latency will be around 40ms.

[topic and first two senctences of commit message changed -Mathias]
Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-05 11:01:58 +02:00
Mathias Nyman 8ca1358bd9 xhci: add port status tracing
Track the port status in a human readble way each time we get a
port status change event

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-16 15:26:26 -07:00
Mathias Nyman 76a0f32b28 xhci: rename temp and temp1 variables
temp and temp1 variables are used for port status (portsc) and
command register. Give them more descriptive names

No functional changes

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-16 15:26:26 -07:00
Mathias Nyman 4b895868bb xhci: Fix NULL pointer dereference when cleaning up streams for removed host
This off by one in stream_id indexing caused NULL pointer dereference and
soft lockup on machines with USB attached SCSI devices connected to a
hotpluggable xhci controller.

The code that cleans up pending URBs for dead hosts tried to dereference
a stream ring at the invalid stream_id 0.
ep->stream_info->stream_rings[0] doesn't point to a ring.

Start looping stream_id from 1 like in all the other places in the driver,
and check that the ring exists before trying to kill URBs on it.

Reported-by: rocko r <rockorequin@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-20 14:40:35 +02:00
Mathias Nyman 3134bc9c52 xhci: cleanup finish_td() skip option
finish_td() could be called with a skip option to bypass most of the
function and only call xhci_td_cleanup() at the end.

Remove this skip option and call xhci_td_cleanup() directly instead
when needed

No functional changes

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-15 22:17:46 +02:00
Mathias Nyman d36374fdfb xhci: cleanup virtual endoint structure, remove stopped_stream
Get rid of stopped_stream member in virtual endpoint structure as
it is only used in one case when cleaning a halted endpoint.

Pass it as function parameter instead.

No functional changes

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-15 22:17:46 +02:00
Mathias Nyman ade2e3a148 xhci: handle transfer events without TRB pointer
Most transfer events have a TRB pointer indicating which TRB caused
the event.
In the case of streams, transfer events such as
USB Transaction error may have its TRB pointer set to zero.

driver won't know which stream or what TRB on that stream caused
the error, but it can issue a soft reset to recover the transfer.
A soft reset will clear the host side halt of the endpoint without
clearing Data toggle or sequence number, and let the transfer
continue from where it halted.

see xhci section 4.12 streams and 4.6.8.2 soft retry.

USB Transaction errors with a zero TRB pointer are seen with
UAS usb devices.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-15 22:17:46 +02:00
Mathias Nyman 5eee4b6b4f xhci: support calling cleanup_halted_endpoint with soft retry
Add soft reset support to cleanup_halted_endpoint().
using soft reset will prevent it from setting a new dequeue pointer to
start the transfer from. Let it continue where it halted.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-15 22:17:46 +02:00
Mathias Nyman 217491487c xhci: Add support for endpoint soft reset
xhci supports soft retry recovery when the host halted the host side of an
endopint but the connected USB device is not aware of the halt.

In this case xhci needs to issue a reset endopint command  with a TSP
(Transfer State Preserve) flag set which preserves the Data toggle
and Sequence number of the endpoint.

This feature is needed to handle a few special transfer event types
such as USB Transaction error that don't always point to a causing TRB.

see xhci 4.6.8.1 for more details

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-15 22:17:46 +02:00
Mathias Nyman b3368382ef xhci: refactor transfer event errors and completion codes
Parse the transfer event first, and remove duplicate debugging
code.

Reorder completion codes according to endpoint state.

No functional changes

We are not handling some transfer events correcly and need to
clean up this before fixing it

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-15 22:17:46 +02:00
Mathias Nyman e6b20121c6 xhci: Add helper to get hardware dequeue pointer for stopped rings.
Add xhci_get_hw_deq() helper to retrieve the hardware dequeue pointer an
endpoint or stream stopped on.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03 18:02:58 +09:00
Mathias Nyman 8790736dbf xhci: Add stream id to xhci_dequeue_state structure
The values for the new dequeue segment, new dequeue pointer and new cycle
state are needed for manually moving the xHC ring dequeue pointer.
These are conveniently stored in a xhci_dequeue_state structure.

stream support was added later and stream_id was carried
as a function parameter.

Move the stream_id to the xhci_dequeue_state structure instead.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03 18:02:58 +09:00
Mathias Nyman cdd504e113 xhci: Find out where an endpoint or stream stopped from its context.
When xHC is asked to stop an endpoint it will save the position it
stopped on in the endpoint or stream context.

xhci driver needs to know if the controller stopped on the exact same
TRB that the driver was asked to cancel as it then needs to move past
the TD instead of turning the TD to no-op TRBs.

xhci driver used to get the stopped position from a "stopped" transfer
event before the stop endpoint command completed, but if the ring
is already stopped, or in a halted or error state this event is missing.

Get the stopped position from the endpoint or stream context instead

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03 18:02:58 +09:00
Mathias Nyman 11e1d25db6 xhci: remove unused stopped_td pointer
We no longer keep track of where we stopped in a stopped_td pointer.
We get the ring dequeue pointer from the endpoint or stream context

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03 18:02:58 +09:00
Mathias Nyman 604d02a2a6 xhci: Fix command ring stop regression in 4.11
In 4.11 TRB completion codes were renamed to match spec.

Completion codes for command ring stopped and endpoint stopped
were mixed, leading to failures while handling a stopped command ring.

Use the correct completion code for command ring stopped events.

Fixes: 0b7c105a04 ("usb: host: xhci: rename completion codes to match spec")
Cc: <stable@vger.kernel.org> # 4.11
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18 15:19:42 +02:00
Alan Stern 63aea0dbab USB: xhci: fix lock-inversion problem
With threaded interrupts, bottom-half handlers are called with
interrupts enabled.  Therefore they can't safely use spin_lock(); they
have to use spin_lock_irqsave().  Lockdep warns about a violation
occurring in xhci_irq():

=========================================================
[ INFO: possible irq lock inversion dependency detected ]
4.11.0-rc8-dbg+ #1 Not tainted
---------------------------------------------------------
swapper/7/0 just changed the state of lock:
 (&(&ehci->lock)->rlock){-.-...}, at: [<ffffffffa0130a69>]
ehci_hrtimer_func+0x29/0xc0 [ehci_hcd]
but this lock took another, HARDIRQ-unsafe lock in the past:
 (hcd_urb_list_lock){+.....}

and interrupts could create inverse lock ordering between them.

other info that might help us debug this:
 Possible interrupt unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(hcd_urb_list_lock);
                               local_irq_disable();
                               lock(&(&ehci->lock)->rlock);
                               lock(hcd_urb_list_lock);
  <Interrupt>
    lock(&(&ehci->lock)->rlock);
 *** DEADLOCK ***

no locks held by swapper/7/0.
the shortest dependencies between 2nd lock and 1st lock:
 -> (hcd_urb_list_lock){+.....} ops: 252 {
    HARDIRQ-ON-W at:
                      __lock_acquire+0x602/0x1280
                      lock_acquire+0xd5/0x1c0
                      _raw_spin_lock+0x2f/0x40
                      usb_hcd_unlink_urb_from_ep+0x1b/0x60 [usbcore]
                      xhci_giveback_urb_in_irq.isra.45+0x70/0x1b0 [xhci_hcd]
                      finish_td.constprop.60+0x1d8/0x2e0 [xhci_hcd]
                      xhci_irq+0xdd6/0x1fa0 [xhci_hcd]
                      usb_hcd_irq+0x26/0x40 [usbcore]
                      irq_forced_thread_fn+0x2f/0x70
                      irq_thread+0x149/0x1d0
                      kthread+0x113/0x150
                      ret_from_fork+0x2e/0x40

This patch fixes the problem.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-and-tested-by: Bart Van Assche <bart.vanassche@sandisk.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18 15:19:42 +02:00
Peter Chen 6a29beef9d usb: host: xhci-ring: don't need to clear interrupt pending for MSI enabled hcd
According to xHCI spec Figure 30: Interrupt Throttle Flow Diagram

	If PCI Message Signaled Interrupts (MSI or MSI-X) are enabled,
       	then the assertion of the Interrupt Pending (IP) flag in Figure 30
       	generates a PCI Dword write. The IP flag is automatically cleared
       	by the completion of the PCI write.

the MSI enabled HCs don't need to clear interrupt pending bit, but
hcd->irq = 0 doesn't equal to MSI enabled HCD. At some Dual-role
controller software designs, it sets hcd->irq as 0 to avoid HCD
requesting interrupt, and they want to decide when to call usb_hcd_irq
by software.

Signed-off-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18 15:19:41 +02:00
Mathias Nyman 7bc5d5aff3 usb: xhci: trace URB before giving it back instead of after
Don't access any members of a URB after giving it back.
URB might be freed by then already.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18 15:19:41 +02:00
Lu Baolu 8c10152ec5 usb: xhci: remove xhci_debug_trb()
Every XHCI TRB has already been traced by the trb trace events.
It is unnecessary to put the same message in kernel log. This
patch removes xhci_debug_trb().

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08 12:17:42 +02:00
Lu Baolu 121dcf1190 usb: xhci: remove ring debugging code
XHCI ring changes have already been traced by the ring trace
events. It's unnecessary to put the same messages in kernel
log. This patch removes the debugging code for a ring.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08 12:17:41 +02:00
Lu Baolu cd12fd9f6d usb: xhci: remove enq_updates and deq_updates from ring
enq_updates and deq_updates were introduced in the first place
to check whether an xhci hardware is able to respond to trbs
enqueued in the ring. We now have trb tracers to trace every
single enqueue/dequeue trb. It's time to remove them and the
associated debugging code.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08 12:17:41 +02:00
Lu Baolu 74e0b5649c usb: xhci: remove error messages for failed memory allocation
Omit extra messages for memory allocation failure.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08 12:17:41 +02:00
Lu Baolu b2d6edbb95 usb: xhci: add xhci_log_ring trace events
This patch creates a new event class called xhci_log_ring, and
defines the events used for tracing the change of all kinds of
rings used by an xhci host. An xHCI ring is basically a memory
block shared between software and hardware. By tracing changes
of rings, it makes the life easier for debugging hardware or
software problems.

This info can be used, later, to print, in a human readable way,
the life cycle of an xHCI ring using the trace-cmd tool and the
appropriate plugin.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08 12:17:41 +02:00
Mathias Nyman d9f11ba9f1 xhci: Rework how we handle unresponsive or hoptlug removed hosts
Introduce a new xhci_hc_died() function that takes care of handling
pending commands and URBs if a host controller becomes unresponsive.

This addresses issues on hotpluggable xhci controllers that disappear
from the bus suddenly, often while the bus (PCI) remove function is
still being processed.

xhci_hc_died() sets a XHCI_STATUS_DYING flag to prevent new URBs and
commands or to be queued. The flag also ensures xhci_hc_died() will
give back pending commands and URBs once.

Host is considered dead if register read returns 0xffffffff, or host
fails to abort the command ring, or fails stopping an endpoint after
trying for 5 seconds.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08 12:17:41 +02:00
Zhengjun Xing b7f769ae1b xhci: add slot and endpoint numbers to debug messages in handle_tx_event
There's one annoyance in how xhci prints debug messages, we often
get logs with messages but it's hard to say from which device and
endpoint the message originates. Add slot_id, ep_index messages
in handle_tx_event.

Signed-off-by: Zhengjun Xing <zhengjun.xing@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08 12:17:41 +02:00
Felipe Balbi 19a7d0d65c usb: host: xhci: add Slot and EP Context tracers
With these, we can track what's happening with the HW while executing
each and every command. It will give us visibility into how the
different contexts are being modified by xHC which can bring insight
into problems while debugging.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08 12:17:41 +02:00
Mathias Nyman 0ab2881a40 xhci: Set URB actual length for stopped control transfers
A control transfer that stopped at the status stage incorrectly
warned about a "unexpected TRB Type 4", and did not set the
transferred actual_length for the URB.

The URB actual_length for control transfers should contain the
bytes transferred in the data stage.

Bytes of a partially sent setup stage and missing bytes from
status stage should be left out.

Cc: <stable@vger.kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-29 12:13:49 +02:00
Mathias Nyman 7e64b0373a xhci: simplify how we store TDs in urb private data
Instead of storing a zero length array of td pointers, and then
allocate memory both for the td pointer array and the td's, just
use a zero length array of actual td's in urb private data.

old:

struct urb_priv {
       struct xhci_td *td[0]
}

new:

struct urb_priv {
        struct xhci_td td[0]
}

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 11:00:02 +01:00
Mathias Nyman 9ef7fbbb4f xhci: Rename variables related to transfer descritpors
urb_priv structure has a count on how many TDs the
URB contains, and how many of those TD's we have handled.

rename:
length -> num_tds
td_cnt -> num_tds_done

No functional changes

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 11:00:02 +01:00
Felipe Balbi 5abdc2e6e1 usb: host: xhci: add urb_enqueue/dequeue/giveback tracers
These three new tracers will help us tie TRBs into URBs by *also*
looking into URB lifetime.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 11:00:01 +01:00
Felipe Balbi a37c3f76e6 usb: host: xhci: make a generic TRB tracer
instead of having a tracer that can only trace command completions,
let's promote this tracer so it can trace and decode any TRB.

With that, it will be easier to extrapolate the lifetime of any TRB
which might help debugging certain issues.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 11:00:01 +01:00
Felipe Balbi a54cfae3c7 usb: host: xhci: convert to list_for_each_entry_safe()
instead of using while(!list_empty()) followed by list_first_entry(), we
can actually use list_for_each_entry_safe().

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 10:59:07 +01:00
Mathias Nyman 5278204c98 xhci: use the trb_to_noop() helper for command trbs
Remove duplicate code by using trb_to_noop() when
handling Aborted commads

Based on earlier code by Felipe Balbi <felipe.balbi@linux.intel.com>

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 10:59:07 +01:00
Mathias Nyman ae1e3f0732 xhci: Introduce helper to turn one TRB into a no-op
Useful for turning both transfer and command trbs
into no-ops.

Based on earlier code by Felipe Balbi <felipe.balbi@linux.intel.com>

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 10:59:07 +01:00
Felipe Balbi a60f2f2ffa usb: host: xhci: unconditionally call xhci_unmap_td_bounce_buffer()
xhci_unmap_td_bounce_buffer() already checks for a valid td->bounce_seg
and bails out early if that's invalid. There's no need to check for this
twice.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 10:59:06 +01:00
Felipe Balbi f45e2a0211 usb: host: xhci: check for a valid ring when unmapping bounce buffer
This way we can remove checks for valid ring from call sites of
xhci_unmap_td_bounce_buffer()

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 10:59:06 +01:00
Felipe Balbi f3899a28e2 usb: host: xhci: remove bogus __releases()/__acquires() annotation
handle_tx_event() is not releasing xhci->lock nor reacquiring it, remove
the bogus annotation.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 10:59:06 +01:00
Felipe Balbi 55fa4396b2 usb: host: xhci: introduce xhci_td_cleanup()
By extracting xhci_td_cleanup() from finish_td(), code before clearer
and easier to follow.

There are no functional changes with this patch. It's merely a cleanup.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 10:59:06 +01:00
Felipe Balbi be0f50c2e3 usb: host: xhci: reorder variable definitions
no functional changes. Simple cleanup to make sure variables are ordered
in a 'reverse christmas tree' fashion. While at that, also remove an
obsolete comment which doesn't apply anymore.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 10:59:06 +01:00
Felipe Balbi 04861f8336 usb: host: xhci: use slightly better list helpers
Replace list_entry() with list_first_entry() and list_for_each() with
list_for_each_entry(). This makes the code slightly more readable.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 10:59:06 +01:00
Felipe Balbi 76a35293b9 usb: host: xhci: simplify irq handler return
Instead of having several return points, let's use a local variable and
a single place to return. This makes the code slightly easier to read.

[set ret = IRQ_HANDLED in default working case  -Mathias]
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 10:59:06 +01:00
Felipe Balbi 0b7c105a04 usb: host: xhci: rename completion codes to match spec
Cleanup only. This patch is a mechaninal rename to make sure our macros
for TRB completion codes match what the specification uses to refer to
such errors. The idea behind this is that it makes it far easier to grep
the specification and match it with implementation.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 10:59:06 +01:00
Lu Baolu daa47f2132 usb: xhci: use list_is_singular for cmd_list
Use list_is_singular() to check if cmd_list has only one entry.

[use list_empty() in queue command instead -Mathias]
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 10:57:35 +01:00
Lu Baolu fb79a6da45 usb: xhci: avoid unnecessary calculation
No need to calculate remainder and length_field, if there is
no data phase of a control transfer.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 10:57:35 +01:00
Lu Baolu 80c479622f usb: xhci: remove unnecessary assignment
Drop an unnecessary assignment in prepare_transfer().

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 10:57:35 +01:00
Lu Baolu 1cc6d8617b usb: xhci: remove unnecessary second abort try
The second try was a workaround for (what we thought was) command
ring failing to stop in the first place. But this turns out to be
due to the race that we have fixed(see "xhci: Fix race related to
abort operation"). With that fix, it is time to remove the second
try.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 10:57:35 +01:00
Mathias Nyman 6b02e97491 xhci: remove unnecessary check for pending timer
Checking if the command timeout timer is pending when queueing the
first command to the command ring is not really useful, remove it.

Suggested-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 10:57:35 +01:00
Mathias Nyman f99265965b xhci: detect stop endpoint race using pending timer instead of counter.
A counter was used to find out if the stop endpoint completion raced with
the stop endpoint timeout timer. This was needed in case the stop ep
completion failed to delete the timer as it was running on anoter cpu.

The EP_STOP_CMD_PENDING flag was not enough as a new stop endpoint command
may be queued between the command completion and timeout function, which
would set the flag back.

Instead of the separate counter that was used we can detect the race by
checking both the STOP_EP_PENDING flag and timer_pending in the timeout
function.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 10:57:34 +01:00
Mathias Nyman 9983a5fc39 xhci: rename EP_HALT_PENDING to EP_STOP_CMD_PENDING
We don't want to confuse halted and stalled endpoint states with
a flag indicating we are waiting for a stop endpoint command to
finish or timeout

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 10:57:34 +01:00
Mathias Nyman 505f581c48 xhci: simplify if statement to make it more readable
No functional change, De Morgan !(A && B) = (!A || !B)

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 10:57:34 +01:00
Mathias Nyman d6169d0409 xhci: fix deadlock at host remove by running watchdog correctly
If a URB is killed while the host is removed we can end up in a situation
where the hub thread takes the roothub device lock, and waits for
the URB to be given back by xhci-hcd, blocking the host remove code.

xhci-hcd tries to stop the endpoint and give back the urb, but can't
as the host is removed from PCI bus at the same time, preventing the normal
way of giving back urb.

Instead we need to rely on the stop command timeout function to give back
the urb. This xhci_stop_endpoint_command_watchdog() timeout function
used a XHCI_STATE_DYING flag to indicate if the timeout function is already
running, but later this flag has been taking into use in other places to
mark that xhci is dying.

Remove checks for XHCI_STATE_DYING in xhci_urb_dequeue. We are still
checking that reading from pci state does not return 0xffffffff or that
host is not halted before trying to stop the endpoint.

This whole area of stopping endpoints, giving back URBs, and the wathdog
timeout need rework, this fix focuses on solving a specific deadlock
issue that we can then send to stable before any major rework.

Cc: <stable@vger.kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-11 16:52:13 +01:00
Felipe Balbi 29fc1aa454 usb: host: xhci: handle COMP_STOP from SETUP phase too
Stop Endpoint command can come at any point and we
have no control of that. We should make sure to
handle COMP_STOP on SETUP phase as well, otherwise
urb->actual_length might be set to negative values
in some occasions such as below:

 urb->length = 4;
 build_control_transfer_td_for(urb, ep);

 					stop_endpoint(ep);

COMP_STOP:
	[...]
	urb->actual_length = urb->length - trb->length;

trb->length is 8 for SETUP stage (8 control request
bytes), so actual_length would be set to -4 in this
case.

While doing that, also make sure to use TRB_TYPE
field of the actual TRB instead of matching pointers
to figure out in which stage of the control transfer
we got our completion event.

Cc: <stable@vger.kernel.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-03 17:37:32 +01:00
OGAWA Hirofumi 1c111b6c38 xhci: Fix race related to abort operation
Current abort operation has race.

    xhci_handle_command_timeout()
      xhci_abort_cmd_ring()
        xhci_write_64(CMD_RING_ABORT)
        xhci_handshake(5s)
	  do {
	    check CMD_RING_RUNNING
            udelay(1)
					 ...
					 COMP_CMD_ABORT event
					 COMP_CMD_STOP event
					 xhci_handle_stopped_cmd_ring()
					   restart cmd_ring
                                           CMD_RING_RUNNING become 1 again
	  } while ()
          return -ETIMEDOUT
        xhci_write_64(CMD_RING_ABORT)
        /* can abort random command */

To do abort operation correctly, we have to wait both of COMP_CMD_STOP
event and negation of CMD_RING_RUNNING.

But like above, while timeout handler is waiting negation of
CMD_RING_RUNNING, event handler can restart cmd_ring. So timeout
handler never be notice negation of CMD_RING_RUNNING, and retry of
CMD_RING_ABORT can abort random command (BTW, I guess retry of
CMD_RING_ABORT was workaround of this race).

To fix this race, this moves xhci_handle_stopped_cmd_ring() to
xhci_abort_cmd_ring().  And timeout handler waits COMP_CMD_STOP event.

At this point, timeout handler is owner of cmd_ring, and safely
restart cmd_ring by using xhci_handle_stopped_cmd_ring().

[FWIW, as bonus, this way would be easily extend to add CMD_RING_PAUSE
operation]

[locks edited as patch is rebased on other locking fixes -Mathias]
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-03 17:37:32 +01:00
OGAWA Hirofumi cb4d5ce588 xhci: Use delayed_work instead of timer for command timeout
This is preparation to fix abort operation race (See "xhci: Fix race
related to abort operation"). To make timeout sleepable, use
delayed_work instead of timer.

[change a newly added pending timer fix to pending work -Mathias]
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-03 17:37:32 +01:00
Lu Baolu 4dea70778c usb: xhci: hold lock over xhci_abort_cmd_ring()
In command timer function, xhci_handle_command_timeout(), xhci->lock
is unlocked before call into xhci_abort_cmd_ring(). This might cause
race between the timer function and the event handler.

The xhci_abort_cmd_ring() function sets the CMD_RING_ABORT bit in the
command register and polling it until the setting takes effect. A stop
command ring event might be handled between writing the abort bit and
polling for it. The event handler will restart the command ring, which
causes the failure of polling, and we ever believed that we failed to
stop it.

As a bonus, this also fixes some issues of calling functions without
locking in xhci_handle_command_timeout().

Cc: <stable@vger.kernel.org> # 3.7+
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-03 17:37:32 +01:00
Mathias Nyman a5a1b95141 xhci: Handle command completion and timeout race
If we get a command completion event at the same time as the command
timeout work starts on another cpu we might end up aborting the wrong
command.

If the command completion takes the xhci lock before the timeout work, it
will handle the command, pick the next command, mark it as current_cmd, and
re-queue the timeout work. When the timeout work finally gets the lock
It will start aborting the wrong command.

This case can be resolved by checking if the timeout work is pending inside
the timeout function itself. A new timeout work can only be pending if the
command completed and a new command was queued.

If there are no more commands pending then command completion will set
the current_cmd to NULL, which is already handled in the timeout work.

Cc: <stable@vger.kernel.org>
Reported-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-03 17:37:32 +01:00
Baolin Wang 2a7cfdf37b usb: host: xhci: Fix possible wild pointer when handling abort command
When current command was supposed to be aborted, host will free the command
in handle_cmd_completion() function. But it might be still referenced by
xhci->current_cmd, which need to set NULL.

Cc: <stable@vger.kernel.org>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-03 17:37:32 +01:00
Lu Baolu 2b98546737 usb: xhci: fix possible wild pointer
handle_cmd_completion() frees a command structure which might be still
referenced by xhci->current_cmd.
This might cause problem when xhci->current_cmd is accessed after that.

A real-life case could be like this. The host takes a very long time to
respond to a command, and the command timer is fired at the same time
when the command completion event arrives. The command completion
handler frees xhci->current_cmd before the timer function can grab
xhci->lock. Afterward, timer function grabs the lock and go ahead with
checking and setting members of xhci->current_cmd.

Cc: <stable@vger.kernel.org> # v3.16+
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-03 17:37:32 +01:00
Greg Kroah-Hartman ae4d814bf1 usb: patches for v4.10 merge window
One big merge this time with a total of 166 non-merge commits.
 
 Most of the work, by far, is on dwc2 this time (68.2%) with dwc3 a far
 second (22.5%). The remaining 9.3% are scattered on gadget drivers.
 
 The most important changes for dwc2 are the peripheral side DMA support
 implemented by Synopsys folks and support for the new IOT dwc2
 compatible core from Synopsys.
 
 In dwc3 land we have support for high-bandwidth, high-speed isochronous
 endpoints and some non-critical fixes for large scatter lists.
 
 Apart from these, we have our usual set of cleanups, non-critical fixes,
 etc.
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Merge tag 'usb-for-v4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-next

Felipe writes:

usb: patches for v4.10 merge window

One big merge this time with a total of 166 non-merge commits.

Most of the work, by far, is on dwc2 this time (68.2%) with dwc3 a far
second (22.5%). The remaining 9.3% are scattered on gadget drivers.

The most important changes for dwc2 are the peripheral side DMA support
implemented by Synopsys folks and support for the new IOT dwc2
compatible core from Synopsys.

In dwc3 land we have support for high-bandwidth, high-speed isochronous
endpoints and some non-critical fixes for large scatter lists.

Apart from these, we have our usual set of cleanups, non-critical fixes,
etc.
2016-11-18 16:02:15 +01:00
Lu Baolu c2d3d49bba usb: xhci: move slot_id from xhci_hcd to xhci_command structure
xhci->slot_id is used for providing a way to pass slot id from the
command completion handler to the function waiting for completion.
It's shared by enumerations of all USB devices connected to an
xhci host. Hence, it's a source for possible races. Since we've
introduced command structure and the command queue to xhci driver.
It's better to move slot_id from xhci_hcd structure to xhci_command
structure. Hence the race source is removed.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-14 10:18:23 +01:00
Mathias Nyman 5071e6b279 xhci: add helper to get the endpoint state of a endpoint context
define GET_EP_CTX_STATE() macro to get the endpoint state from a
pointer to a le32 enpoint context structure

No functional changes

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-14 10:18:22 +01:00
Lu Baolu f4c8f03ca3 usb: xhci: clean up error_bitmask usage
In xhci_handle_event(), when errors are detected, driver always sets
a bit in error_bitmask (one member of the xhci private driver data).
That means users have to retrieve and decode the value of error_bitmask
in xhci private driver data if they want to know whether those erros
ever happened in xhci_handle_event(). Otherwise, those errors are just
ignored silently.

This patch cleans up this by replacing the setting of error_bitmask
with the kernel print functions, so that users can easily check and
report the errors happened in xhci_handle_event().

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-14 10:18:22 +01:00
Mathias Nyman 2a72126de1 xhci: Remove duplicate xhci urb giveback functions
We want one function that gives back urb in interrupt that can
be used in both normal cases and when killing off urbs.

Add small helpers that check if td is last_td_in_urb() and
that increase the td count of a urb inc_td_cnt()

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-14 10:18:22 +01:00
Mathias Nyman 0c03d89d0c xhci: Giveback urb in finish_td directly
mostly refactoring and code cleanup.

while handling transfer events we used to check the return value of
various functions to see if we can give back the URB.
Turns out the only case when those return values are set are when
finish_td() notices we are completing the last td in the URB.

give back the urb directly in finish_td() instead.

Only functional change is that we now increase the event ring dequeue
pointer in sowtware after giving back the URB. This should not matter
as we are in hardware interrupt context and the time when writing the
new event ring dequeue to hardware remains the same.
Hardware is the only one that can put event TRBs on the event ring.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-14 10:18:22 +01:00
Mathias Nyman 446b31419c xhci: refactor handle_tx_event() urb giveback
Move giving back the urb to a separate function
No functional changes

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-14 10:18:22 +01:00
Wei Yongjun 2d6d5769f8 xhci: fix non static symbol warning
Fixes the following sparse warning:

drivers/usb/host/xhci-ring.c:608:6: warning:
 symbol 'xhci_unmap_td_bounce_buffer' was not declared.
 Should it be static?

Signed-off-by: Wei Yongjun <weiyj.lk@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-14 10:18:22 +01:00
Mathias Nyman 0d58a1a047 xhci: cleanup and refactor td_to_noop()
No functional changes but a few debugging outputs removed

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-14 10:18:22 +01:00
Mathias Nyman 36da3a1dd8 xhci: refactor and cleanup process_isoc_td()
No functional changes

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-14 10:18:22 +01:00
Mathias Nyman f97c08ae32 xhci: rename endpoint related trb variables
Renaming variables, no functional changes

Event trbs on the event ring cointain a pointer to the transfer trb
on a endpoint ring that caused the event.

The naming has been very confusing as the event trb was called "event"
and the endpoint transfer trb was called "event_trb".

rename all variables that are realated to the endpoint transfer trb
from event_* to ep_*

No functional changes

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-14 10:18:21 +01:00
Mathias Nyman 30a65b45bf xhci: cleanup and refactor process_bulk_intr_td()
mostly refactoring, but does also change error message if
we get a bad length in the event trb.

Adds a helper function to sum trb lengths of partial TDs

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-14 10:18:21 +01:00
Mathias Nyman 0b6c324c8b xhci: cleanup and refactor process_ctrl_td()
Refactor pricess_ctrl_tx() to make it more readable
No functional changes

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-14 10:18:21 +01:00
Mathias Nyman 52ab86852f xhci: remove extra URB_SHORT_NOT_OK checks in xhci, core handles most cases
We only check for the URB_SHORT_NOT_OK urb flag to set the urb status
to -EREMOTEIO for transfers that didn't transfer all data.

This will be done in __usb_hcd_giveback() for other than isoc tranfers,
so remove the redundant check from xhci.

Also fix a couple split lines in debug messages to make them greppable.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-14 10:18:21 +01:00
Mathias Nyman 0ce5749959 xhci: add trb_is_noop() helper function
replace the complex check for noop with a simple helper
Improve code readability

No functional changes

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-14 10:18:21 +01:00
Mathias Nyman 3495e451d1 xhci: use trb helper functions when possible
Use the trb_is_link() and link_trb_toggles_cycle() helpers to
make the code more readable

No functional changes

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-14 10:18:21 +01:00
Mathias Nyman cf5d344e13 xhci: remove unnecessary xhci_quiesce call before xhci_halt
Fist function called in xhci_halt is xhci_quiesce, so no point
in calling it twice

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-14 10:18:21 +01:00
Felipe Balbi 734d3ddd81 usb: host: xhci: purge GET_MAX_PACKET()
usb_endpoint_maxp() is now returning maxpacket
correctly - iow only bits 10:0. We can finaly remove
XHCI's private GET_MAX_PACKET macro.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2016-11-03 10:38:22 +02:00
Mathias Nyman bcf42aa60c xhci: fix null pointer dereference in stop command timeout function
The stop endpoint command has its own 5 second timeout timer.
If the timeout function is triggered between USB3 and USB2 host
removal it will try to call usb_hc_died(xhci_to_hcd(xhci)->primary_hcd)

the ->primary_hcd will be set to NULL at USB3 hcd removal.

Fix this by first checking if the PCI host is being removed, and
also by using only xhci_to_hcd() as it will always return the primary
hcd.

CC: <stable@vger.kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-08 08:39:46 +02:00
Alban Browaeys 0d2daaded8 xhci: really enqueue zero length TRBs.
Enqueue the first TRB even if full_len is zero.
Without this "adb install <apk>" freezes the system.

Signed-off-by: Alban Browaeys <alban.browaeys@gmail.com>
Fixes: 86065c2719 ("xhci: don't rely on precalculated value of needed trbs in the enqueue loop")
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-16 09:42:47 +02:00
Mathias Nyman 33be126510 xhci: always handle "Command Ring Stopped" events
Fix "Command completion event does not match command" errors by always
handling the command ring stopped events.

The command ring stopped event is generated as a result of aborting
or stopping the command ring with a register write. It is not caused
by a command in the command queue, and thus won't have a matching command
in the comman list.

Solve it by handling the command ring stopped event before checking for a
matching command.

In most command time out cases we abort the command ring, and get
a command ring stopped event. The events command pointer will point at
the current command ring dequeue, which in most cases matches the timed
out command in the command list, and no error messages are seen.

If we instead get a command aborted event before the command ring stopped
event, the abort event will increse the command ring dequeue pointer, and
the following command ring stopped events command pointer will point at the
next, not yet queued command. This case triggered the error message

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-16 09:42:47 +02:00
Arnd Bergmann f76a28a69a xhci: free the correct ring
gcc warns about what first looks like a reference to an uninitialized
variable:

drivers/usb/host/xhci-ring.c: In function 'handle_cmd_completion':
drivers/usb/host/xhci-ring.c:753:4: error: 'ep_ring' may be used uninitialized in this function [-Werror=maybe-uninitialized]
    xhci_unmap_td_bounce_buffer(xhci, ep_ring, cur_td);
    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/usb/host/xhci-ring.c:647:20: note: 'ep_ring' was declared here
  struct xhci_ring *ep_ring;
                    ^~~~~~~

It's clear to see that the list_empty() check means it can never be
uninitialized, however it still looks wrong:

When ep->cancelled_td_list contains more than one entry, the
ep_ring variable will point to the ring that was retrieved
from the last urb, and we have to look it up again in the
second loop instead, which fixes the behavior and gets rid of the
warning too.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: f9c589e142 ("xhci: TD-fragment, align the unsplittable case with a bounce buffer")
Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-07-01 08:59:44 -07:00
Mathias Nyman d0c77d84b4 xhci: rename and simplify last_trb_on_last_seg() helper
It's only used with rings that have link trbs

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-26 11:43:39 -07:00
Mathias Nyman 549310ab5d xhci: remove enqueue_is_link() helper
Only used in one place, replace with trb_is_link() helper

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-26 11:43:39 -07:00
Mathias Nyman bd5e67f59a xhci: rework inc_deq() and fix off by one error.
inc_deq() is called both for rings with link trbs and the event ring
without link trbs.
The last_trb() check in inc_deq() has a off by one error, going beyond
allocated array when checking if trb == [TRBS_PER_SEGMENT], and the whole
inc_deq() depend on this.

Rewrite the inc_deq() funciton, remove the faulty last_trb() helper, add
new last_trb_on_seg() and last_trb_on_ring() helpers

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-26 11:43:39 -07:00
Mathias Nyman 2d98ef406f xhci: use and add separate function for checking for link trbs
Add a new is_link_trb() function that only checks for link trbs.
We want to split generic last_trb() function which is used for both
event rings without link trbs, and endpoint and command rings with links.

This will allow us to easier check for link trbs added mid segments.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-26 11:43:39 -07:00
Mathias Nyman 2251198bef xhci: clean up event ring checks from inc_enq()
Remove the event ring related checks in inc_enq()

Host hardware is the producer of events on the event ring,
driver will not queue anything, or call inc_enq() for the
event ring.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-26 11:43:39 -07:00
Mathias Nyman f9c589e142 xhci: TD-fragment, align the unsplittable case with a bounce buffer
If the last trb before a link is not packet size aligned, and is not
splittable then use a bounce buffer for that chunk of max packet size
unalignable data.

Allocate a max packet size bounce buffer for every segment of a bulk
endpoint ring at the same time as allocating the ring.
If we need to align the data before the link trb in that segment then
copy the data to the segment bounce buffer, dma map it, and enqueue it.
Once the td finishes, or is cancelled, unmap it.

For in transfers we need to first map the bounce buffer, then queue it,
after it finishes, copy the bounce buffer to the original sg list, and
finally unmap it

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-26 11:43:39 -07:00
Mathias Nyman 474ed23a62 xhci: align the last trb before link if it is easily splittable.
TD fragments section 4.11.7.1 in xhci specs have additional requirements
on how trbs in TDs must be organized.

TD fragments shall not span transfer ring segments and TD fragments must
be packet aligned. Normally we don't care about TD fragments, on TD is one
big fragment, but if a TD spans ring segments it will be treated as two
fragments, and we need to comply with the alignment requirements.

For us this means that the payload data must be packet aligned in the
last trb before a link trb.
In most mass storage bulk tranfers we are lucky as the block size aligns
nicely with packet size, and there are no issues.
However, usb network adapters using scatterlists can hit this alignment
issue, and usbtest in kernel triggers this in minutes.

This patch is a partial solution, it solves the easy case when the last
trb before the link trb contains a packet boundary.
If that is the case then just split the trb at the boundary.
If not, then just print a debug message and continue as we have always
done, hoping for the best

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-26 11:43:39 -07:00
Mathias Nyman 86065c2719 xhci: don't rely on precalculated value of needed trbs in the enqueue loop
Queue trbs until all payload data in the urb is tranferred.

The actual number of trbs might need to change from the pre-calculated
number when the packet alignment restrictions for td fragments in
xhci 4.11.7.1 are taken into account.

Long term plan is to get rid of calculating the needed trbs in advance
all together. It's an unnecessary extra walk through the scatterlist.

This change also allows some bulk queue function simplifications

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-26 11:43:39 -07:00
Mathias Nyman 124c393711 xhci: use boolean to indicate last trb in td remainder calculation
We only need to know if we are queuing the last trb for a TD when
calculating the td remainder field.
The total number of trbs left is not used.

We won't be able to trust the pre-calculated number of trbs used if we
need to align trb data by splitting or merging trbs in order to satisfy
comply with data alignment requirements in xhci specs section 4.11.7.1.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-26 11:43:39 -07:00
Mathias Nyman 5a83f04a79 xhci: properly prepare zero packet TD after normal bulk TD.
If a zero-length packet is needed after a bulk transfer, then an
additional zero length TD was prepared before enqueueing the bulk transfer
This set up the zero packet TD structure with incorrect td->start_seg
and td->first_trb pointers.

Prepare the zero packet TD after the data bulk TD is enqueued instead.
It sets these pointers correctly.

This change also simplifies unnecessary complexity related to keeping
track of the last trb when enqueuing trbs.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-26 11:43:39 -07:00
Mathias Nyman 5a5a0b1ae5 xhci: rename ep_ring variable in queue_bulk_tx(), no functional change
Tiny change, a bit more readable.
The real reason for this change is that the coming td fragment work
had several over 80 lines character lines split just because of a few
extra characters in variable names.

no functional changes

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-26 11:43:39 -07:00
Mathias Nyman 3425aa03f4 xhci: Fix handling timeouted commands on hosts in weird states.
If commands timeout we mark them for abortion, then stop the command
ring, and turn the commands to no-ops and finally restart the command
ring.

If the host is working properly the no-op commands will finish and
pending completions are called.
If we notice the host is failing, driver clears the command ring and
completes, deletes and frees all pending commands.

There are two separate cases reported where host is believed to work
properly but is not. In the first case we successfully stop the ring
but no abort or stop command ring event is ever sent and host locks up.

The second case is if a host is removed, command times out and driver
believes the ring is stopped, and assumes it will be restarted, but
actually ends up timing out on the same command forever.
If one of the pending commands has the xhci->mutex held it will block
xhci_stop() in the remove codepath which otherwise would cleanup pending
commands.

Add a check that clears all pending commands in case host is removed,
or we are stuck timing out on the same command. Also restart the
command timeout timer when stopping the command ring to ensure we
recive an ring stop/abort event.

Cc: stable <stable@vger.kernel.org>
Tested-by: Joe Lawrence <joe.lawrence@stratus.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-01 14:55:01 -07:00
Gabriel Krisman Bertazi 27a41a83ec xhci: Cleanup only when releasing primary hcd
Under stress occasions some TI devices might not return early when
reading the status register during the quirk invocation of xhci_irq made
by usb_hcd_pci_remove.  This means that instead of returning, we end up
handling this interruption in the middle of a shutdown.  Since
xhci->event_ring has already been freed in xhci_mem_cleanup, we end up
accessing freed memory, causing the Oops below.

commit 8c24d6d7b0 ("usb: xhci: stop everything on the first call to
xhci_stop") is the one that changed the instant in which we clean up the
event queue when stopping a device.  Before, we didn't call
xhci_mem_cleanup at the first time xhci_stop is executed (for the shared
HCD), instead, we only did it after the invocation for the primary HCD,
much later at the removal path.  The code flow for this oops looks like
this:

xhci_pci_remove()
	usb_remove_hcd(xhci->shared)
	        xhci_stop(xhci->shared)
 			xhci_halt()
			xhci_mem_cleanup(xhci);  // Free the event_queue
	usb_hcd_pci_remove(primary)
		xhci_irq()  // Access the event_queue if STS_EINT is set. Crash.
		xhci_stop()
			xhci_halt()
			// return early

The fix modifies xhci_stop to only cleanup the xhci data when releasing
the primary HCD.  This way, we still have the event_queue configured
when invoking xhci_irq.  We still halt the device on the first call to
xhci_stop, though.

I could reproduce this issue several times on the mainline kernel by
doing a bind-unbind stress test with a specific storage gadget attached.
I also ran the same test over-night with my patch applied and didn't
observe the issue anymore.

[  113.334124] Unable to handle kernel paging request for data at address 0x00000028
[  113.335514] Faulting instruction address: 0xd00000000d4f767c
[  113.336839] Oops: Kernel access of bad area, sig: 11 [#1]
[  113.338214] SMP NR_CPUS=1024 NUMA PowerNV

[c000000efe47ba90] c000000000720850 usb_hcd_irq+0x50/0x80
[c000000efe47bac0] c00000000073d328 usb_hcd_pci_remove+0x68/0x1f0
[c000000efe47bb00] d00000000daf0128 xhci_pci_remove+0x78/0xb0
[xhci_pci]
[c000000efe47bb30] c00000000055cf70 pci_device_remove+0x70/0x110
[c000000efe47bb70] c00000000061c6bc __device_release_driver+0xbc/0x190
[c000000efe47bba0] c00000000061c7d0 device_release_driver+0x40/0x70
[c000000efe47bbd0] c000000000619510 unbind_store+0x120/0x150
[c000000efe47bc20] c0000000006183c4 drv_attr_store+0x64/0xa0
[c000000efe47bc60] c00000000039f1d0 sysfs_kf_write+0x80/0xb0
[c000000efe47bca0] c00000000039e14c kernfs_fop_write+0x18c/0x1f0
[c000000efe47bcf0] c0000000002e962c __vfs_write+0x6c/0x190
[c000000efe47bd90] c0000000002eab40 vfs_write+0xc0/0x200
[c000000efe47bde0] c0000000002ec85c SyS_write+0x6c/0x110
[c000000efe47be30] c000000000009260 system_call+0x38/0x108

Signed-off-by: Gabriel Krisman Bertazi <krisman@linux.vnet.ibm.com>
Cc: Roger Quadros <rogerq@ti.com>
Cc: joel@jms.id.au
Cc: stable@vger.kernel.org
Reviewed-by: Roger Quadros <rogerq@ti.com>
Cc: <stable@vger.kernel.org> #v4.3+
Tested-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-01 14:55:01 -07:00
Alexandr Ivanov 78140156f4 usb: xhci: remove duplicate code of interval checking
Move duplicate code from xhci_queue_intr_tx()
and xhci_queue_isoc_tx_prepare() to the check_interval() function.

Signed-off-by: Alexandr Ivanov <alexandr.sky@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-26 16:08:02 -07:00
Alexandr Ivanov 75b040ec60 usb: xhci: remove duplicate function xhci_urb_to_transfer_ring
Remove duplicate function xhci_urb_to_transfer_ring from xhci.c.
We have same function in xhci-ring.c.

Signed-off-by: Alexandr Ivanov <alexandr.sky@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-26 16:08:02 -07:00
Alexandr Ivanov d2510342fe usb: xhci: merge xhci_queue_bulk_tx and queue_bulk_sg_tx functions
In drivers/usb/host/xhci-ring.c there are two functions
(xhci_queue_bulk_tx and queue_bulk_sg_tx) that are very similar,
so a lot of code duplication.
This patch merges these functions into to one xhci_queue_bulk_tx.
Also counting the needed TRBs is merged and refactored.

Signed-off-by: Alexandr Ivanov <alexandr.sky@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-26 16:08:02 -07:00
Rajesh Bhagat d4fc8bf597 xhci: fix typo in babble endpoint handling comment
The 0.95 xHCI spec says that non-control endpoints will be halted if a
babble is detected on a transfer.  The 0.96 xHCI spec says all types of
endpoints will be halted when a babble is detected.  Some hardware that
claims to be 0.95 compliant halts the control endpoint anyway.

Reference: http://www.spinics.net/lists/linux-usb/msg21755.html

Signed-off-by: Rajesh Bhagat <rajesh.bhagat@nxp.com>
Reviewed-by: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-19 04:33:15 +09:00
Mathias Nyman 98d74f9cea xhci: fix 10 second timeout on removal of PCI hotpluggable xhci controllers
PCI hotpluggable xhci controllers such as some Alpine Ridge solutions will
remove the xhci controller from the PCI bus when the last USB device is
disconnected.

Add a flag to indicate that the host is being removed to avoid queueing
configure_endpoint commands for the dropped endpoints.
For PCI hotplugged controllers this will prevent 5 second command timeouts
For static xhci controllers the configure_endpoint command is not needed
in the removal case as everything will be returned, freed, and the
controller is reset.

For now the flag is only set for PCI connected host controllers.

Cc: <stable@vger.kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-13 11:55:56 -07:00