linux/drivers/usb/wusbcore/wa-nep.c
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00

306 lines
8.9 KiB
C

/*
* WUSB Wire Adapter: Control/Data Streaming Interface (WUSB[8])
* Notification EndPoint support
*
* Copyright (C) 2006 Intel Corporation
* Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version
* 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*
*
* This part takes care of getting the notification from the hw
* only and dispatching through wusbwad into
* wa_notif_dispatch. Handling is done there.
*
* WA notifications are limited in size; most of them are three or
* four bytes long, and the longest is the HWA Device Notification,
* which would not exceed 38 bytes (DNs are limited in payload to 32
* bytes plus 3 bytes header (WUSB1.0[7.6p2]), plus 3 bytes HWA
* header (WUSB1.0[8.5.4.2]).
*
* It is not clear if more than one Device Notification can be packed
* in a HWA Notification, I assume no because of the wording in
* WUSB1.0[8.5.4.2]. In any case, the bigger any notification could
* get is 256 bytes (as the bLength field is a byte).
*
* So what we do is we have this buffer and read into it; when a
* notification arrives we schedule work to a specific, single thread
* workqueue (so notifications are serialized) and copy the
* notification data. After scheduling the work, we rearm the read from
* the notification endpoint.
*
* Entry points here are:
*
* wa_nep_[create|destroy]() To initialize/release this subsystem
*
* wa_nep_cb() Callback for the notification
* endpoint; when data is ready, this
* does the dispatching.
*/
#include <linux/workqueue.h>
#include <linux/ctype.h>
#include <linux/slab.h>
#include "wa-hc.h"
#include "wusbhc.h"
/* Structure for queueing notifications to the workqueue */
struct wa_notif_work {
struct work_struct work;
struct wahc *wa;
size_t size;
u8 data[];
};
/*
* Process incoming notifications from the WA's Notification EndPoint
* [the wuswad daemon, basically]
*
* @_nw: Pointer to a descriptor which has the pointer to the
* @wa, the size of the buffer and the work queue
* structure (so we can free all when done).
* @returns 0 if ok, < 0 errno code on error.
*
* All notifications follow the same format; they need to start with a
* 'struct wa_notif_hdr' header, so it is easy to parse through
* them. We just break the buffer in individual notifications (the
* standard doesn't say if it can be done or is forbidden, so we are
* cautious) and dispatch each.
*
* So the handling layers are is:
*
* WA specific notification (from NEP)
* Device Notification Received -> wa_handle_notif_dn()
* WUSB Device notification generic handling
* BPST Adjustment -> wa_handle_notif_bpst_adj()
* ... -> ...
*
* @wa has to be referenced
*/
static void wa_notif_dispatch(struct work_struct *ws)
{
void *itr;
u8 missing = 0;
struct wa_notif_work *nw = container_of(ws, struct wa_notif_work, work);
struct wahc *wa = nw->wa;
struct wa_notif_hdr *notif_hdr;
size_t size;
struct device *dev = &wa->usb_iface->dev;
#if 0
/* FIXME: need to check for this??? */
if (usb_hcd->state == HC_STATE_QUIESCING) /* Going down? */
goto out; /* screw it */
#endif
atomic_dec(&wa->notifs_queued); /* Throttling ctl */
dev = &wa->usb_iface->dev;
size = nw->size;
itr = nw->data;
while (size) {
if (size < sizeof(*notif_hdr)) {
missing = sizeof(*notif_hdr) - size;
goto exhausted_buffer;
}
notif_hdr = itr;
if (size < notif_hdr->bLength)
goto exhausted_buffer;
itr += notif_hdr->bLength;
size -= notif_hdr->bLength;
/* Dispatch the notification [don't use itr or size!] */
switch (notif_hdr->bNotifyType) {
case HWA_NOTIF_DN: {
struct hwa_notif_dn *hwa_dn;
hwa_dn = container_of(notif_hdr, struct hwa_notif_dn,
hdr);
wusbhc_handle_dn(wa->wusb, hwa_dn->bSourceDeviceAddr,
hwa_dn->dndata,
notif_hdr->bLength - sizeof(*hwa_dn));
break;
}
case WA_NOTIF_TRANSFER:
wa_handle_notif_xfer(wa, notif_hdr);
break;
case DWA_NOTIF_RWAKE:
case DWA_NOTIF_PORTSTATUS:
case HWA_NOTIF_BPST_ADJ:
/* FIXME: unimplemented WA NOTIFs */
/* fallthru */
default:
dev_err(dev, "HWA: unknown notification 0x%x, "
"%zu bytes; discarding\n",
notif_hdr->bNotifyType,
(size_t)notif_hdr->bLength);
break;
}
}
out:
wa_put(wa);
kfree(nw);
return;
/* THIS SHOULD NOT HAPPEN
*
* Buffer exahusted with partial data remaining; just warn and
* discard the data, as this should not happen.
*/
exhausted_buffer:
dev_warn(dev, "HWA: device sent short notification, "
"%d bytes missing; discarding %d bytes.\n",
missing, (int)size);
goto out;
}
/*
* Deliver incoming WA notifications to the wusbwa workqueue
*
* @wa: Pointer the Wire Adapter Controller Data Streaming
* instance (part of an 'struct usb_hcd').
* @size: Size of the received buffer
* @returns 0 if ok, < 0 errno code on error.
*
* The input buffer is @wa->nep_buffer, with @size bytes
* (guaranteed to fit in the allocated space,
* @wa->nep_buffer_size).
*/
static int wa_nep_queue(struct wahc *wa, size_t size)
{
int result = 0;
struct device *dev = &wa->usb_iface->dev;
struct wa_notif_work *nw;
/* dev_fnstart(dev, "(wa %p, size %zu)\n", wa, size); */
BUG_ON(size > wa->nep_buffer_size);
if (size == 0)
goto out;
if (atomic_read(&wa->notifs_queued) > 200) {
if (printk_ratelimit())
dev_err(dev, "Too many notifications queued, "
"throttling back\n");
goto out;
}
nw = kzalloc(sizeof(*nw) + size, GFP_ATOMIC);
if (nw == NULL) {
if (printk_ratelimit())
dev_err(dev, "No memory to queue notification\n");
goto out;
}
INIT_WORK(&nw->work, wa_notif_dispatch);
nw->wa = wa_get(wa);
nw->size = size;
memcpy(nw->data, wa->nep_buffer, size);
atomic_inc(&wa->notifs_queued); /* Throttling ctl */
queue_work(wusbd, &nw->work);
out:
/* dev_fnend(dev, "(wa %p, size %zu) = result\n", wa, size, result); */
return result;
}
/*
* Callback for the notification event endpoint
*
* Check's that everything is fine and then passes the data to be
* queued to the workqueue.
*/
static void wa_nep_cb(struct urb *urb)
{
int result;
struct wahc *wa = urb->context;
struct device *dev = &wa->usb_iface->dev;
switch (result = urb->status) {
case 0:
result = wa_nep_queue(wa, urb->actual_length);
if (result < 0)
dev_err(dev, "NEP: unable to process notification(s): "
"%d\n", result);
break;
case -ECONNRESET: /* Not an error, but a controlled situation; */
case -ENOENT: /* (we killed the URB)...so, no broadcast */
case -ESHUTDOWN:
dev_dbg(dev, "NEP: going down %d\n", urb->status);
goto out;
default: /* On general errors, we retry unless it gets ugly */
if (edc_inc(&wa->nep_edc, EDC_MAX_ERRORS,
EDC_ERROR_TIMEFRAME)) {
dev_err(dev, "NEP: URB max acceptable errors "
"exceeded, resetting device\n");
wa_reset_all(wa);
goto out;
}
dev_err(dev, "NEP: URB error %d\n", urb->status);
}
result = wa_nep_arm(wa, GFP_ATOMIC);
if (result < 0) {
dev_err(dev, "NEP: cannot submit URB: %d\n", result);
wa_reset_all(wa);
}
out:
return;
}
/*
* Initialize @wa's notification and event's endpoint stuff
*
* This includes the allocating the read buffer, the context ID
* allocation bitmap, the URB and submitting the URB.
*/
int wa_nep_create(struct wahc *wa, struct usb_interface *iface)
{
int result;
struct usb_endpoint_descriptor *epd;
struct usb_device *usb_dev = interface_to_usbdev(iface);
struct device *dev = &iface->dev;
edc_init(&wa->nep_edc);
epd = &iface->cur_altsetting->endpoint[0].desc;
wa->nep_buffer_size = 1024;
wa->nep_buffer = kmalloc(wa->nep_buffer_size, GFP_KERNEL);
if (wa->nep_buffer == NULL) {
dev_err(dev, "Unable to allocate notification's read buffer\n");
goto error_nep_buffer;
}
wa->nep_urb = usb_alloc_urb(0, GFP_KERNEL);
if (wa->nep_urb == NULL) {
dev_err(dev, "Unable to allocate notification URB\n");
goto error_urb_alloc;
}
usb_fill_int_urb(wa->nep_urb, usb_dev,
usb_rcvintpipe(usb_dev, epd->bEndpointAddress),
wa->nep_buffer, wa->nep_buffer_size,
wa_nep_cb, wa, epd->bInterval);
result = wa_nep_arm(wa, GFP_KERNEL);
if (result < 0) {
dev_err(dev, "Cannot submit notification URB: %d\n", result);
goto error_nep_arm;
}
return 0;
error_nep_arm:
usb_free_urb(wa->nep_urb);
error_urb_alloc:
kfree(wa->nep_buffer);
error_nep_buffer:
return -ENOMEM;
}
void wa_nep_destroy(struct wahc *wa)
{
wa_nep_disarm(wa);
usb_free_urb(wa->nep_urb);
kfree(wa->nep_buffer);
}