From bea3348eef27e6044b6161fd04c3152215f96411 Mon Sep 17 00:00:00 2001 From: Stephen Hemminger Date: Wed, 3 Oct 2007 16:41:36 -0700 Subject: [NET]: Make NAPI polling independent of struct net_device objects. Several devices have multiple independant RX queues per net device, and some have a single interrupt doorbell for several queues. In either case, it's easier to support layouts like that if the structure representing the poll is independant from the net device itself. The signature of the ->poll() call back goes from: int foo_poll(struct net_device *dev, int *budget) to int foo_poll(struct napi_struct *napi, int budget) The caller is returned the number of RX packets processed (or the number of "NAPI credits" consumed if you want to get abstract). The callee no longer messes around bumping dev->quota, *budget, etc. because that is all handled in the caller upon return. The napi_struct is to be embedded in the device driver private data structures. Furthermore, it is the driver's responsibility to disable all NAPI instances in it's ->stop() device close handler. Since the napi_struct is privatized into the driver's private data structures, only the driver knows how to get at all of the napi_struct instances it may have per-device. With lots of help and suggestions from Rusty Russell, Roland Dreier, Michael Chan, Jeff Garzik, and Jamal Hadi Salim. Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra, Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan. [ Ported to current tree and all drivers converted. Integrated Stephen's follow-on kerneldoc additions, and restored poll_list handling to the old style to fix mutual exclusion issues. -DaveM ] Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller --- Documentation/DocBook/kernel-api.tmpl | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'Documentation/DocBook') diff --git a/Documentation/DocBook/kernel-api.tmpl b/Documentation/DocBook/kernel-api.tmpl index b886f52..e5da4f2b 100644 --- a/Documentation/DocBook/kernel-api.tmpl +++ b/Documentation/DocBook/kernel-api.tmpl @@ -240,17 +240,23 @@ X!Ilib/string.c Driver Support !Enet/core/dev.c !Enet/ethernet/eth.c +!Enet/sched/sch_generic.c !Iinclude/linux/etherdevice.h +!Iinclude/linux/netdevice.h + + PHY Support !Edrivers/net/phy/phy.c !Idrivers/net/phy/phy.c !Edrivers/net/phy/phy_device.c !Idrivers/net/phy/phy_device.c !Edrivers/net/phy/mdio_bus.c !Idrivers/net/phy/mdio_bus.c + +--> Synchronous PPP !Edrivers/net/wan/syncppp.c -- cgit v1.1 From 3a2fbff228f773e3628bc26a688d40b2214af025 Mon Sep 17 00:00:00 2001 From: Cornelia Huck Date: Fri, 12 Oct 2007 16:11:18 +0200 Subject: [S390] cio: Add s390-drivers book. s390-drivers is generated using the docbook comments. It should eventually supersede Documentation/s390/cds.txt. Signed-off-by: Cornelia Huck Signed-off-by: Martin Schwidefsky Signed-off-by: Heiko Carstens --- Documentation/DocBook/Makefile | 2 +- Documentation/DocBook/s390-drivers.tmpl | 149 ++++++++++++++++++++++++++++++++ 2 files changed, 150 insertions(+), 1 deletion(-) create mode 100644 Documentation/DocBook/s390-drivers.tmpl (limited to 'Documentation/DocBook') diff --git a/Documentation/DocBook/Makefile b/Documentation/DocBook/Makefile index 08687e4..1a7f530 100644 --- a/Documentation/DocBook/Makefile +++ b/Documentation/DocBook/Makefile @@ -11,7 +11,7 @@ DOCBOOKS := wanbook.xml z8530book.xml mcabook.xml videobook.xml \ procfs-guide.xml writing_usb_driver.xml \ kernel-api.xml filesystems.xml lsm.xml usb.xml \ gadget.xml libata.xml mtdnand.xml librs.xml rapidio.xml \ - genericirq.xml + genericirq.xml s390-drivers.xml ### # The build process is as follows (targets): diff --git a/Documentation/DocBook/s390-drivers.tmpl b/Documentation/DocBook/s390-drivers.tmpl new file mode 100644 index 0000000..254e769 --- /dev/null +++ b/Documentation/DocBook/s390-drivers.tmpl @@ -0,0 +1,149 @@ + + + + + + Writing s390 channel device drivers + + + + Cornelia + Huck + +
+ cornelia.huck@de.ibm.com +
+ + + + + + 2007 + IBM Corp. + + + + + This documentation is free software; you can redistribute + it and/or modify it under the terms of the GNU General Public + License as published by the Free Software Foundation; either + version 2 of the License, or (at your option) any later + version. + + + + 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., 59 Temple Place, Suite 330, Boston, + MA 02111-1307 USA + + + + For more details see the file COPYING in the source + distribution of Linux. + + + + + + + + Introduction + + This document describes the interfaces available for device drivers that + drive s390 based channel attached devices. This includes interfaces for + interaction with the hardware and interfaces for interacting with the + common driver core. Those interfaces are provided by the s390 common I/O + layer. + + + The document assumes a familarity with the technical terms associated + with the s390 channel I/O architecture. For a description of this + architecture, please refer to the "z/Architecture: Principles of + Operation", IBM publication no. SA22-7832. + + + While most I/O devices on a s390 system are typically driven through the + channel I/O mechanism described here, there are various other methods + (like the diag interface). These are out of the scope of this document. + + + Some additional information can also be found in the kernel source + under Documentation/s390/driver-model.txt. + + + + The ccw bus + + The ccw bus typically contains the majority of devices available to + a s390 system. Named after the channel command word (ccw), the basic + command structure used to address its devices, the ccw bus contains + so-called channel attached devices. They are addressed via subchannels, + visible on the css bus. A device driver, however, will never interact + with the subchannel directly, but only via the device on the ccw bus, + the ccw device. + + + I/O functions for channel-attached devices + + Some hardware structures have been translated into C structures for use + by the common I/O layer and device drivers. For more information on + the hardware structures represented here, please consult the Principles + of Operation. + +!Iinclude/asm-s390/cio.h + + + ccw devices + + Devices that want to initiate channel I/O need to attach to the ccw bus. + Interaction with the driver core is done via the common I/O layer, which + provides the abstractions of ccw devices and ccw device drivers. + + + The functions that initiate or terminate channel I/O all act upon a + ccw device structure. Device drivers must not bypass those functions + or strange side effects may happen. + +!Iinclude/asm-s390/ccwdev.h +!Edrivers/s390/cio/device.c +!Edrivers/s390/cio/device_ops.c + + + The channel-measurement facility + + The channel-measurement facility provides a means to collect + measurement data which is made available by the channel subsystem + for each channel attached device. + +!Iinclude/asm-s390/cmb.h +!Edrivers/s390/cio/cmf.c + + + + + The ccwgroup bus + + The ccwgroup bus only contains artificial devices, created by the user. + Many networking devices (e.g. qeth) are in fact composed of several + ccw devices (like read, write and data channel for qeth). The + ccwgroup bus provides a mechanism to create a meta-device which + contains those ccw devices as slave devices and can be associated + with the netdevice. + + + ccw group devices +!Iinclude/asm-s390/ccwgroup.h +!Edrivers/s390/cio/ccwgroup.c + + + + -- cgit v1.1