Commit Graph

35 Commits

Author SHA1 Message Date
Gerd Hoffmann e0423dee89 USB: uas: fix gcc warning
Streamline control flow so it is easier for gcc to follow which paths
can be taken and which can't.

Fixes "warning: 'cmdinfo' may be used uninitialized in this function"

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-26 14:13:19 -07:00
Gerd Hoffmann 1994ff405e USB: uas: fix locking
Forgot to unlock in the uas_eh_task_mgmt error paths.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-26 14:13:19 -07:00
Gerd Hoffmann e064852072 USB: uas: add locking
Add spinlock to protect uas data structures.

[ v2: s/GFP_NOIO/GFP_ATOMIC/, better don't sleep when holding a spinlock ]

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-25 15:32:23 -07:00
Gerd Hoffmann 0871d7d86c USB: uas: fix abort
Properly report aborted commands.
Also don't access cmdinfo after kicking task management,
it may not be valid any more once it returns.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-25 15:32:23 -07:00
Gerd Hoffmann ef018cc9f8 USB: uas: remove aborted field, replace with status bit.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-25 15:32:23 -07:00
Gerd Hoffmann 0393986495 USB: uas: fix task management
Allocate one tag for task management functions and
use it properly.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-25 15:32:23 -07:00
Gerd Hoffmann a0e39e3468 USB: uas: keep track of command urbs
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-25 15:32:23 -07:00
Gerd Hoffmann 023b515e5b uas: task mgmt & error handling
Add task management support, wind up in abort and device reset error
handlers.  Cancel all in-flight urbs in bus reset handler.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-25 11:51:01 -07:00
Gerd Hoffmann bdd000fb34 uas: track urbs, kill inflight urbs on disconnect.
Use separate anchors for data and sense urbs, which
I think will be useful when implementing error handling.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-25 11:51:00 -07:00
Gerd Hoffmann 8aac863e92 uas: improve error handling
(1) Handle data pipe errors: When the data urb failed we
    didn't transfer anything, update scsi_cmnd accordingly.
(2) Cancel data transfers when we got back an error on the
    status pipe.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-25 11:51:00 -07:00
Gerd Hoffmann b1d6769333 uas: keep track of command state, finish scsi cmd when really done.
Set state bits after submitting data urbs & command urbs, so we know
what is in flight.  Clear data bits when the data urb is finished, clear
command bit when we see the status urb for the command.  Finish the scsi
command after running both status and data completion handlers for the
command.

Add a cmd status logging function for debugging purposes.  Hook it into
the error handler, so we see in the log what status a command is in
which the scsi layer wants cancel.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-25 11:50:59 -07:00
Gerd Hoffmann e9bd7e1a2d uas: fix sense urb handling
Stop reusing sense urbs, just allocate a fresh one each time and free it
when done.

Stop storing a sense urb pointer in the scsi request, all you can do
with it is misusing.  For example requeuing the sense urb, then f*ck it
up by picking the wrong one in case tagged requests don't finish in the
same order you've submitted them.  Also note that (not-yet supported)
task management ops don't have a scsi request in the first place.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-25 11:50:59 -07:00
Gerd Hoffmann db32de11f7 Revert "usb/uas: one only one status URB/host on stream-less connection"
This reverts commit ceb3f91fd5.

IMO the real bug is assigning status urbs to scsi requests.  First there
is no such link in the non-stream case.  Also there isn't nessesarely a
scsi request in the first place, for example when submitting task
management requests.

This patch just papers over the real bug and introduces different status
urb handling in the stream/non-stream case for no good reason.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-25 11:50:59 -07:00
Gerd Hoffmann c621a81ede Revert "usb/uas: make sure data urb is gone if we receive status before that"
This reverts commit e4d8318a85.

This patch makes uas.c call usb_unlink_urb on data urbs.  The data urbs
get freed in the completion callback.  This is illegal according to the
usb_unlink_urb documentation.

This patch also makes the code expect the data completion callback
being called before the status completion callback.  This isn't
guaranteed to be the case, even though the actual data transfer should
be finished by the time the status is received.

Background:  The ehci irq handler for example only know that there are
finished transfers, it then has go check the QHs & TDs to see which
transfers did actually finish.  It has no way to figure in which order
the transfers did complete.  The xhci driver can call the callbacks in
completion order thanks to the event queue.  This does nicely explain
why the driver is solid on a (usb2) xhci port whereas it goes crazy on
ehci in my testing.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-25 11:50:58 -07:00
Sebastian Andrzej Siewior e4d8318a85 usb/uas: make sure data urb is gone if we receive status before that
Just run into the following:
- new disk arrived in the system
- udev couldn't wait to get its hands on to to run ata_id /dev/sda
- this sent the cdb 0xa1 to the device.
- my UAS-gadget recevied the cdb and had no idea what to do with it. It
  decided to send a status URB back with sense set to invalid opcode.
- the host side received it status and completed the scsi command.
- the host sent another scsi with 4kib data buffer
- Now I was confused why the data transfer is only 512 bytes instead of
  4kib since the host is always allocating the complete transfer in one
  go.
- Finally the system crashed while walking through the sg list.

This patch adds three new flags in order to distinguish between DATA
URB completed and outstanding. If we receive status before data, we
cancel data and let data complete the command.
This solves the problem for IN and OUT transfers but does not work for
BIDI.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2012-02-02 14:51:30 -08:00
Sebastian Andrzej Siewior 348748b0e8 usb/uas: move UAS structs / defines into a header file
The protocol specific structures and defines which are used by UAS are
moved into a header files by this patch so it can be accessed by the UAS
gadget as well.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2012-02-02 14:51:11 -08:00
Sebastian Andrzej Siewior c898add51c usb/uas: only bind if the hcd supports SG
The UAS driver requires SG support by the HCD operating the device. This
patch stops UAS from operating on a HCD without sg support and prints a
message to let him know.

The spec says:
|For [USB2] backward compatibility, the device shall present [BOT] as
|alternate interface zero (primary) and [UAS] as alternate interface one
|(secondary). A device which does not need backward compatibility with
|[BOT] shall present [UAS] as alternate interface zero. In [USB2]
|systems, the [BOT] driver or an associated filter driver may need to
|issue a SET INTERFACE request for alternate interface one and then allow
|the [UAS] driver to load.

If the user used usb_modeswitch to switch to UAS then he can go back to
BOT or use a different HCD. In case UAS is the only interface then there
is currently no way out.
In future usb_sg_wait() should be extended to provide a non-blocking
interface so it can work with the UAS driver.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2012-02-02 14:51:00 -08:00
Sarah Sharp b603669842 UAS fixes for Sarah
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Merge tag 'uas_for_sarah' of git://linutronix.de/users/bigeasy/linux into for-uas-next

Merge UAS bug fixes from Sebastian Andrzej Siewior, including some patches of
mine that he signed.

UAS fixes for Sarah
2012-02-02 14:47:14 -08:00
Sebastian Andrzej Siewior ceb3f91fd5 usb/uas: one only one status URB/host on stream-less connection
The status/sense URB is allocated on per-command basis. A read/write
looks the following way on a stream-less connection:

- send cmd tag X, queue status
- receive status, oh it is a read for tag X. queue status & read
- receive read
- receive status, oh I'm done for tag X. Cool call complete and free
  status urb.

This block repeats itself 1:1 for further commands and looks great so
far. Lets take a look now what happens if we do allow multiple commands:

- send cmd tag X, queue statusX (belongs to the command with the X tag)
- send cmd tag Y, queue statusY (belongs to the command with the Y tag)
- receive statusX, oh it is a read for tag X. queue statusX & a read
- receive read
- receive statusY, oh I'm done for tag X. Cool call complete and free statusY.
- receive statusX, oh it is a read for tag Y. queue statusY & before we
  queue the read the the following message can be observed:
  |sd 0:0:0:0: [sda] sense urb submission failure
  followed by a second attempt with the same result.

In order to address this problem we will use only one status URB for
each scsi host in case we don't have stream support (as suggested by
Matthew). This URB is requeued until the device removed. Nothing changes
on stream based endpoints.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
2011-12-22 11:28:19 +01:00
Sebastian Andrzej Siewior 22188f4a93 usb/uas: use scsi_host_find_tag() to find command from a tag
In "usb/uas: use unique tags for all LUNs" we make sure to create unique
tags across all LUNs. This patch uses scsi_host_find_tag() to obtain the
correct command which is associated with the tag.
The following changes are required:
- don't use sdev->current_cmnd anymore
  Since we can have devices which don't support command queueing we must
  ensure that we can tell the two commands apart. Even if a device
  supports comand queuing we send the INQUIRY command "untagged" for
  LUN1 while we can send a tagged command to LUN0 at the same time.
  devinfo->cmnd is used for stashing the one "untagged" command.
- tag number is altered. If stream support is used then the tag number
  must match the stream number. Therefore we can't use tag 0 and must
  start at tag 1.
  In case we have untagged commands (at least the first command) we must
  be able to distinguish between command tag 0 (which becomes 1) and
  untagged command (which becomes curently also 1).
  The following tag numbers are used:
  0: never
  1: for untagged commands (devinfo->cmnd)
  2+: tagged commands.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
2011-12-22 10:36:19 +01:00
Sebastian Andrzej Siewior dae51546b6 usb/uas: use unique tags for all LUNs
I observed that on a device with multiple LUNs UAS was re-using the same
tag number for requests which were issued at the same time to both LUNs.
This patch uses scsi_init_shared_tag_map() to use unique tags for all
LUNs. With this patch I haven't seen the same tag number during the init
sequence anymore. Tag 1 is used for devices which do not adverise
command queueing.
This patch initilizes the queue before adding the scsi host like the
other two user in tree.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
2011-12-22 10:14:49 +01:00
Sarah Sharp 96c1eb9873 UAS: Free status URB when we can't find the SCSI tag.
In the UAS status URB completion handler, we need to free the URB, no
matter what happens.  Fix a bug where we would leak the URB (and its
buffer) if we couldn't find a SCSI command that is associated with this
status phase.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
2011-12-22 10:14:48 +01:00
Sarah Sharp 9eb445410d UAS: Use unique tags on non-streams devices.
UAS can work with either USB 3.0 devices that support bulk streams, or
USB 2.0 devices that do not support bulk streams.  When we're working
with a non-streams device, we need to be able to uniquely identify a
SCSI command with a tag in the IU.  Devices will barf and abort all
queued commands if they find a duplicate tag.

uas_queuecommand_lck() sets cmdinfo->stream to zero if the device
doesn't support streams, which is later passed into uas_alloc_cmd_urb()
as the variable stream.  This means the UAS driver was setting the tag
in all commands to zero for non-stream devices.  So the UAS driver won't
currently work with USB 2.0 devices.

Use the SCSI command tag instead of the stream ID for the command IU
tag.  We have to add one to the SCSI command tag because SCSI tags are
zero-based, but stream IDs are one-based, and the command tag must match
the stream ID that we're queueing the data IUs for.  Untagged SCSI
commands use stream ID 1.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
2011-12-22 10:14:48 +01:00
Sarah Sharp ea9da1c79e UAS: Re-add workqueue items if submission fails.
If the original submission (or allocation) of the URBs for a SCSI
command fails, the UAS driver sticks the command structure in a
workqueue and schedules uas_do_work() to run.  That function removes the
entire queue before walking across it and attempting to resubmit.

Unfortunately, if the second submission fails, we will leak memory
(because an allocated URB was not submitted) and possibly leave the SCSI
command partially enqueued on some of the stream rings.  Fix this by
checking whether the second submission failed and re-queueing the
command to the UAS workqueue and scheduling it.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
2011-12-22 10:12:54 +01:00
Greg Kroah-Hartman 65db430540 USB: convert drivers/usb/* to use module_usb_driver()
This converts the drivers in drivers/usb/* to use the
module_usb_driver() macro which makes the code smaller and a bit
simpler.

Added bonus is that it removes some unneeded kernel log messages about
drivers loading and/or unloading.

Cc: Simon Arlott <cxacru@fire.lp0.eu>
Cc: Duncan Sands <duncan.sands@free.fr>
Cc: Matthieu CASTET <castet.matthieu@free.fr>
Cc: Stanislaw Gruszka <stf_xl@wp.pl>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: Oliver Neukum <oliver@neukum.name>
Cc: Juergen Stuber <starblue@users.sourceforge.net>
Cc: Cesar Miquel <miquel@df.uba.ar>
Cc: Matthew Dharm <mdharm-usb@one-eyed-alien.net>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Lucas De Marchi <lucas.demarchi@profusion.mobi>
Cc: Michael Hund <mhund@ld-didactic.de>
Cc: Zack Parsons <k3bacon@gmail.com>
Cc: Melchior FRANZ <mfranz@aon.at>
Cc: Tomoki Sekiyama <tomoki.sekiyama@gmail.com>
Cc: Dan Carpenter <error27@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-18 09:34:02 -08:00
Paul Gortmaker 6eb0de8270 usb: Add module.h to drivers/usb consumers who really use it.
The situation up to this point meant that module.h was pretty
much everywhere, regardless of whether you asked for it or not.
We are fixing that, so give the USB folks who want it an actual
include of it.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:31:25 -04:00
Greg Kroah-Hartman 36facadd9e Merge branch 'usb-next' into musb-merge
* usb-next: (132 commits)
  USB: uas: Use GFP_NOIO instead of GFP_KERNEL in I/O submission path
  USB: uas: Ensure we only bind to a UAS interface
  USB: uas: Rename sense pipe and sense urb to status pipe and status urb
  USB: uas: Use kzalloc instead of kmalloc
  USB: uas: Fix up the Sense IU
  usb: musb: core: kill unneeded #include's
  DA8xx: assign name to MUSB IRQ resource
  usb: gadget: g_ncm added
  usb: gadget: f_ncm.c added
  usb: gadget: u_ether: prepare for NCM
  usb: pch_udc: Fix setup transfers with data out
  usb: pch_udc: Fix compile error, warnings and checkpatch warnings
  usb: add ab8500 usb transceiver driver
  USB: gadget: Implement runtime PM for MSM bus glue driver
  USB: gadget: Implement runtime PM for ci13xxx gadget
  USB: gadget: Add USB controller driver for MSM SoC
  USB: gadget: Introduce ci13xxx_udc_driver struct
  USB: gadget: Initialize ci13xxx gadget device's coherent DMA mask
  USB: gadget: Fix "scheduling while atomic" bugs in ci13xxx_udc
  USB: gadget: Separate out PCI bus code from ci13xxx_udc
  ...
2010-12-16 10:05:06 -08:00
Matthew Wilcox 0b83ae960c USB: uas: Use GFP_NOIO instead of GFP_KERNEL in I/O submission path
If swap is on a UAS device, we could recurse into the driver by using
GFP_KERNEL.  Using GFP_NOIO ensures we won't.

Reported-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-12-15 15:26:44 -08:00
Matthew Wilcox 89dc29051b USB: uas: Ensure we only bind to a UAS interface
While all existing UAS devices use alternate interface 1, this is not
guaranteed, and it has caused confusion with people trying to bind the
uas driver to non-uas devices.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-12-15 15:26:44 -08:00
Matthew Wilcox 92a3f767f5 USB: uas: Rename sense pipe and sense urb to status pipe and status urb
The spec calls this the status pipe.  While it is used to receive sense IUs,
it is also used to receive other IUs, so this can be confusing.

Reported-by: Luben Tuikov <ltuikov@yahoo.com>
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-12-15 15:26:44 -08:00
Matthew Wilcox ac563cfd52 USB: uas: Use kzalloc instead of kmalloc
The IUs are not being fully initialised by the driver (due to the reserved
space).  Since we should be zeroing reserved fields, use kzalloc to do
it for us.

Reported-by: Luben Tuikov <ltuikov@yahoo.com>
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-12-15 15:26:44 -08:00
Matthew Wilcox 4400ef311e USB: uas: Fix up the Sense IU
Add a comment to the Sense IU data structure that it's also used for Read
Ready and Write Ready.  Remove the 'service response' element since it's
gone from the current draft (04).

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-12-15 15:26:43 -08:00
Jeff Garzik f281233d3e SCSI host lock push-down
Move the mid-layer's ->queuecommand() invocation from being locked
with the host lock to being unlocked to facilitate speeding up the
critical path for drivers who don't need this lock taken anyway.

The patch below presents a simple SCSI host lock push-down as an
equivalent transformation.  No locking or other behavior should change
with this patch.  All existing bugs and locking orders are preserved.

Additionally, add one parameter to queuecommand,
	struct Scsi_Host *
and remove one parameter from queuecommand,
	void (*done)(struct scsi_cmnd *)

Scsi_Host* is a convenient pointer that most host drivers need anyway,
and 'done' is redundant to struct scsi_cmnd->scsi_done.

Minimal code disturbance was attempted with this change.  Most drivers
needed only two one-line modifications for their host lock push-down.

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Acked-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-16 13:33:23 -08:00
Christoph Hellwig 02e031cbc8 block: remove REQ_HARDBARRIER
REQ_HARDBARRIER is dead now, so remove the leftovers.  What's left
at this point is:

 - various checks inside the block layer.
 - sanity checks in bio based drivers.
 - now unused bio_empty_barrier helper.
 - Xen blockfront use of BLKIF_OP_WRITE_BARRIER - it's dead for a while,
   but Xen really needs to sort out it's barrier situaton.
 - setting of ordered tags in uas - dead code copied from old scsi
   drivers.
 - scsi different retry for barriers - it's dead and should have been
   removed when flushes were converted to FS requests.
 - blktrace handling of barriers - removed.  Someone who knows blktrace
   better should add support for REQ_FLUSH and REQ_FUA, though.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-11-10 14:54:09 +01:00
Matthew Wilcox 115bb1ffa5 USB: Add UAS driver
USB Attached SCSI is a new protocol specified jointly by the SCSI T10
committee and the USB Implementors Forum.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Cc: Matthew Dharm <mdharm-usb@one-eyed-alien.net>
[mina86@mina86.com: updated to use new USB_ prefix]
Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-10-22 10:21:50 -07:00