xHCI driver has its own pci probe function that will call usb_hcd_pci_probe
to register its usb-2 bus, and then continue to manually register the
usb-3 bus. usb_hcd_pci_probe does a pm_runtime_put_noidle at the end and
might thus trigger a runtime suspend before the usb-3 bus is ready.

Prevent the runtime suspend by increasing the usage count in the
beginning of xhci_pci_probe, and decrease it once the usb-3 bus is
ready.

xhci-platform driver is not using usb_hcd_pci_probe to set up
busses and should not need to have it's usage count increased during probe.
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Acked-by: NDan Williams <dan.j.williams@intel.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org

On some older XHCIs streams are not supported and the UAS driver
will fail at probe time. For those devices storage should try
to bind to UAS devices.
This patch adds a flag for stream support to HCDs and evaluates
it.

[Note: Sarah fixed a bug where the USB 2.0 root hub, not USB 3.0 root
hub would get marked as being able to support streams.]
Signed-off-by: NOliver Neukum <oliver@neukum.org>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Acked-by: NHans de Goede <hdegoede@redhat.com>

If the host controller stops responding to commands, we need to kill all
the URBs that were queued to all endpoints.  The current code would only
kill URBs that had been queued to the endpoint rings.  ep->ring is set
to NULL if streams has been enabled for the endpoint, which means URBs
submitted with a non-zero stream_id would never get killed.  Fix this.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

In preparation for fixing this function for streams endpoints, refactor
code in the command watchdog timeout function into two new functions.
One kills all URBs on a ring (either stream or endpoint), the other
kills all URBs associated with an endpoint.  Fix a split string while
we're at it.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Although an interesting concept, I don't think that this is a good idea:

-This will result in lots of "virtual" scsi controllers confusing users
-If we get a scsi-bus-reset we will now need to do a usb-device-reset of all
 uas devices on the same usb bus, which is something to avoid if possible
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

At the kernel-summit Sarah Sharp asked me if I was willing to become the
uas maintainer. I said yes, and here is a patch to make this official.

Also remove Matthew Wilcox and Sarah Sharp as maintainers at their request.

I've also added myself to the module's author tag, so that if people look there
rather then in maintainers they will know they should bug me about uas too.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

xhci streams support is fixed, unblock usb attached scsi.
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Copy the sg alignment trick from the usb-storage driver, without this I'm
seeing intermittent errors when using uas devices with an ehci controller.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

The scsi error handling path re-uses previously queued up (and errored-out)
cmds. If such a re-used cmd had a data-phase then cmdinfo will have
data_in_urb / data_out_urb still set to the free-ed urbs from the errored-out
cmd, and they will get free-ed a second time when the error handling cmd
completes, corrupting the kernel heap.

Clearing cmdinfo on command queue-ing fixes this, and seems like a good idea
in general.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

The scsi-host structure is refcounted, scsi_remove_host tears down the
scsi-host but does not decrement the refcount, so we need to call
scsi_put_host on disconnect to get the underlying memory to be freed.

After calling scsi_remove_host, the scsi-core may still hold a reference to
the scsi-host, iow we may still get called after uas_disconnect, but we
do our own life cycle management of uas_devinfo, freeing it on disconnect,
and thus may end up using devinfo after it has been freed. Switch to letting
scsi_host_alloc allocate and manage the memory for us.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

cmds are either on the inflight list or on the dead list, never both, so
we only need one list head.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Before this commit the uas driver would keep track of scsi commands which still
need to have some urbs submitted to the device, and complete this with an
ABORT result code on bus-reset or disconnect, but in flight scsi commands
which have all their urbs submitted, and thus are not part of the work list,
would never get their done callback called.

The problem is killed sense urbs don't have any tag info, so it is impossible
to tell which scsi cmd they belong to, so merely making sure all the urbs
have completed one way or the other is not enough.

This commit fixes this by changing the work list to an inflight list, which
keeps tracks of all inflight scsi cmnds, using the IS_IN_WORK_LIST flag to
determine if actual work needs to be done in uas_do_work(), and by moving
marking all inflight scsi commands as aborted and moving them to the dead list
on bus-reset or disconnect.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

uas_alloc_data_urb always gets called with a stream_id value of 0 when not
using streams. Removing the check makes it consistent with uas_alloc_sense_urb.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

For USB-2 connections the stream-id must always be 0.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Some BIOS-es will hang on reboot when an uas device is attached and left in
uas mode on reboot.

This commit adds a shutdown handler which on reboot puts the device back into
usb-storage mode, fixing the hang on reboot on these systems.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

We can sleep in our own workqueue (which is the whole reason for having
it), and scsi error handlers are also always called from a context which
may sleep.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Since we use a fixed tag / stream for tasks we cannot allow more then one
to run at the same time. This could happen before this time if a task timed
out.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

The fixed endpoint config code was only necessary to deal with an early
uas prototype which has never been released, so lets drop it and enforce
proper uas endpoint descriptors.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

No changes, just the move.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

The loop uses up to 3 bytes of the endpoint extra data.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

This is a preparation patch for adding better descriptor validation.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Falling back from uas to usb-storage requires coordination between uas and
usb-storage, so use usb-storage's quirks module parameter, rather then
requiring the user to pass a param to 2 different modules.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

uas devices have 2 alternative settings on their usb-storage interface,
one for usb-storage and one for uas. Using the uas driver is preferred, so if
the uas driver is enabled, and the device has an uas alt setting, don't bind.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Once we start supporting uas hardware, and as more and more uas devices
become available, we will likely start seeing broken devices. This patch
prepares for the inevitable need for blacklisting those devices from
using the uas driver (they will use usb-storage instead).
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

On disconnect USB3 protocol ports transit from U0 to SS.Inactive to Rx.Detect,
on a recoverable error, the port stays in SS.Inactive and we recover from it by
doing a warm-reset (through usb_device_reset if we have a udev for the port).

If this really is a disconnect we may end up trying the warm-reset anyways,
since khubd may run before the SS.Inactive to Rx.Detect transition, or it
may get skipped if the transition to Rx.Detect happens before khubd gets run.

With a loose connector, or in the case which actually led me to debugging this
bad ACPI firmware toggling Vbus off and on in quick succession, the port
may transition from Rx.Detect to U0 again before khubd gets run. In this case
the device state is unknown really, but khubd happily goes into the resuscitate
an existing device path, and the device driver never gets notified about the
device state being messed up.

If the above scenario happens with a streams using device, as soon as an urb
is submitted to an endpoint with streams, the following appears in dmesg:

ERROR Transfer event for disabled endpoint or incorrect stream ring
@0000000036807420 00000000 00000000 04000000 04078000

Notice how the TRB address is all zeros. I've seen this both on Intel
Pantherpoint and Nec xhci hosts.

Luckily we can detect the U0 to SS.Inactive to Rx.Detect to U0 all having
happened before khubd runs case since the C_LINK_STATE bit gets set in the
portchange bits on the U0 -> SS.Inactive change. This bit will also be set on
suspend / resume, but then it gets cleared by port_hub_init before khubd runs.

So if the C_LINK_STATE bit is set and a warm-reset is not needed, iow the port
is not still in SS.Inactive, and the port still has a connection, then the
device needs to be reset to put it back in a known state.

I've verified that doing the device reset also fixes the transfer event with
all zeros address issue.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

If streams are still allocated on device-reset or set-interface then the hcd
code implictly frees the streams. Clear host_endpoint->streams in this case
so that if a driver later tries to re-allocate them it won't run afoul of the
device already having streams check in usb_alloc_streams().

Note normally streams still being allocated at reset / set-intf  would be a
driver bug, but this can happen without it being a driver bug on reset-resume.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

If we align segment dma pool memory to 64 bytes, then a segment can be located
at 0x10000040 - 0x1000043f, and a segment from another ring at 0x10000440 -
0x1000083f. The last trb in the first segment at 0x10000430 will then translate
to the same radix tree key as the first trb of the second segment, while they
are in different rings!

This patches fixes this by changing the alignment of the dma pool to be 1KB
rather then 64 bytes. An alternative fix would be to reduce the shift used
to calculate the radix tree keys, but that would (slighlty) grow the radix
trees so I believe this is the better fix.

Note this patch is mostly theoretical since in practice I've not seen
the dma_pool actually return not 1KB aligned memory.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

cmd_ring_reserved_trbs gets decremented by xhci_free_stream_info(), so set it
to 0 after freeing all rings, otherwise it wraps around to a very large value
when rings with streams are free-ed.

Before this patch the wrap-around could be triggered when xhci_resume
calls xhci_mem_cleanup if the controller resume fails.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

This is a preparation patch for teaching usb-storage to not bind to
uas devices.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>