usb: controllers do not need to check for babble themselves

If an (emulated) usb-device tries to write more data to a packet then
its iov len, this will trigger an assert in usb_packet_copy(), and if
a driver somehow circumvents that check and writes more data to the
iov then there is space, we have a much bigger problem then not correctly
reporting babble to the guest.

In practice babble will only happen with (real) redirected devices, and there
both the usb-host os and the qemu usb-device code already check for it.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
usb-core: Don't set packet state to complete on a nak

This way the hcd can re-use the same packet to retry without needing
to re-init it.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
usb-core: Add a usb_ep_find_packet_by_id() helper function

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
usb-core: Allow the first packet of a pipelined ep to complete immediately

This can happen with usb-redir live-migration when the packet gets re-queued
after the migration and the original queuing from the migration source side
has already finished.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Revert "ehci: don't flush cache on doorbell rings."

This reverts commit 9bc3a3a216e2689bfcdd36c3e079333bbdbf3ba0, which got
added to fix an issue where the real, underlying cause was not stopping
the ep queue on an error.

Now that the underlying cause is fixed by the "usb: Halt ep queue and
cancel pending packets on a packet error" patch, the "don't flush" fix
is no longer needed.

Not only is it not needed, it causes us to see cancellations (unlinks)
done by the Linux EHCI driver too late, which in combination with the new
usb-core packet-id generation where qtd addresses are used as ids, causes
duplicate ids for in flight packets.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
ehci: Validate qh is not changed unexpectedly by the guest

-combine the qh check with the check for devaddr changes
-also ensure that p gets set to NULL when the queue gets cancelled on
 devaddr change, which was not done properly before this patch

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
ehci: Update copyright headers to reflect recent work

Update copyright headers to reflect all the work Gerd and I have been doing
on the EHCI emulation.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
ehci: Properly cleanup packets on cancel

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
ehci: Properly report completed but not yet processed packets to the guest

Reported packets which have completed before being cancelled as such to the
host. Note that the new code path this patch adds is untested since it I've
been unable to actually trigger the race which needs this code path.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
ehci: check for EHCI_ASYNC_FINISHED first in ehci_free_packet

Otherwise we'll see the packet free twice in the trace log even though
it actually happens only once.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
ehci: trace guest bugs

make qemu_queue_{cancel,reset} return the number of packets released,
so the caller can figure whenever there have been active packets even
though there shouldn't have been any.  Add tracepoint to log this.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
ehci: add doorbell trace events

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
ehci: Add some additional ehci_trace_guest_bug() calls

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
ehci: Fix memory leak in handling of NAK-ed packets

Currently each time we try to execute a NAK-ed packet we redo
ehci_init_transfer, and usb_packet_map, re-allocing (without freeing) the
sg list every time.

This patch fixes this, it does this by introducing another async state, so
that we also properly cleanup a NAK-ed packet on cancel.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
ehci: Handle USB_RET_PROCERR in ehci_fill_queue

USB_RET_PROCERR can be triggered by the guest (by for example requesting more
then BUFFSIZE bytes), so don't assert on it.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
ehci: Correct a comment in fetchqtd packet processing

Since my previous comment said "Should never happen", I tried changing the
next line to an assert(0), which did not go well, which as the new comments
explains is logical if you think about it for a moment.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
usb-redir: Never return USB_RET_NAK for async handled packets

USB_RET_NAK is not a valid response for async handled packets (and will
trigger an assert as such).

Also drop the warning when receiving a status of cancelled for packets not
cancelled by qemu itself, this can happen when a device gets unredirected
by the usbredir-host while transfers are pending.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
usb-redir: Don't delay handling of open events to a bottom half

There is no need for this, and doing so means that a backend trying to
write immediately after an open event will see qemu_chr_be_can_write
returning 0, which not all backends handle well as there is no wakeup
mechanism to detect when the frontend does become writable.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
usb-redir: Get rid of async-struct get member

This is a preparation patch for completely getting rid of the async-packet
struct in usb-redir, instead relying on the (new) per ep queues in the
qemu usb core.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
usb-redir: Get rid of local shadow copy of packet headers

The shadow copy only serves as an extra check (besides the packet-id) to
ensure the packet we get back is a reply to the packet we think it is.

This check has never triggered in all the time usb-redir is in use now,
and since the verified data in the returned packet-header is not used
otherwise, removing the check does not open any possibilities for the
usbredirhost to confuse us.

This is a preparation patch for completely getting rid of the async-packet
struct in usb-redir, instead relying on the (new) per ep queues in the
qemu usb core.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>