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* samples: connector: from Documentation to samples directoryArnd Bergmann2016-04-281-0/+8
| | | | | | | | | | | | | | A small bug with the new autoksyms support showed that there are two kernel modules in the Documentation directory that qualify as samples, while all other samples are in the samples/ directory. This patch was originally meant as a workaround for that bug, but it has now been solved in a different way. However, I still think it makes sense as a cleanup to consolidate all sample code in one place. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* w1: optional bundling of netlink kernel repliesDavid Fries2014-05-271-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Applications can submit a set of commands in one packet to the kernel, and in some cases it is required such as reading the temperature sensor results. This adds an option W1_CN_BUNDLE to the flags of cn_msg to request the kernel to reply in one packet for efficiency. The cn_msg flags now check for unknown flag values and return an error if one is seen. See "Proper handling of unknown flags in system calls" http://lwn.net/Articles/588444/ This corrects the ack values returned as per the protocol standard, namely the original ack for status messages and seq + 1 for all others such as the data returned from a read. Some of the common variable names have been standardized as follows. struct cn_msg *cn struct w1_netlink_msg *msg struct w1_netlink_cmd *cmd struct w1_master *dev When an argument and a function scope variable would collide, add req_ to the argument. Signed-off-by: David Fries <David@Fries.net> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* connector: allow multiple messages to be sent in one packetDavid Fries2014-05-271-3/+10
| | | | | | | | | | | | | This increases the amount of bundling to reduce the number of packets sent. For the one wire use there can be multiple struct w1_netlink_cmd in a struct w1_netlink_msg and multiple of those in struct cn_msg, and with this change multiple of those in a struct nlmsghdr, and at each level the len identifies there being multiple of the next. Signed-off-by: David Fries <David@Fries.net> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Documentation/: it's -> its where appropriateFrancis Galiegue2010-04-231-1/+1
| | | | | | | | Fix obvious cases of "it's" being used when "its" was meant. Signed-off-by: Francis Galiegue <fgaliegue@gmail.com> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* connector: Provide the sender's credentials to the callbackPhilipp Reisner2009-10-021-4/+4
| | | | | | | Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Acked-by: Lars Ellenberg <lars.ellenberg@linbit.com> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* connector: clean up grammar/style in documentationMike Frysinger2009-07-171-58/+61
| | | | | | | | The grammar in most of this file is slightly off, and some sections are hard to read due to lack of visual clues breaking up related material. Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* [CONNECTOR]: Use netlink_has_listeners() to avoind unnecessary allocations.Evgeniy Polyakov2006-03-201-2/+3
| | | | | | | | | Return -ESRCH from cn_netlink_send() when there are not listeners, just as it could be done by netlink_broadcast(). Propagate netlink_broadcast() error back to the caller. Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: David S. Miller <davem@davemloft.net>
* [CONNECTOR]: Update documentation to match reality.Evgeniy Polyakov2005-10-131-0/+44
| | | | | | | | | Updated documentation to reflect 2.6.14 netlink changes about socket options, multicasting and group number. Please concider for 2.6.14. Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: David S. Miller <davem@davemloft.net>
* [NET]: Add netlink connector.Evgeniy Polyakov2005-09-111-0/+133
Kernel connector - new userspace <-> kernel space easy to use communication module which implements easy to use bidirectional message bus using netlink as it's backend. Connector was created to eliminate complex skb handling both in send and receive message bus direction. Connector driver adds possibility to connect various agents using as one of it's backends netlink based network. One must register callback and identifier. When driver receives special netlink message with appropriate identifier, appropriate callback will be called. From the userspace point of view it's quite straightforward: socket(); bind(); send(); recv(); But if kernelspace want to use full power of such connections, driver writer must create special sockets, must know about struct sk_buff handling... Connector allows any kernelspace agents to use netlink based networking for inter-process communication in a significantly easier way: int cn_add_callback(struct cb_id *id, char *name, void (*callback) (void *)); void cn_netlink_send(struct cn_msg *msg, u32 __groups, int gfp_mask); struct cb_id { __u32 idx; __u32 val; }; idx and val are unique identifiers which must be registered in connector.h for in-kernel usage. void (*callback) (void *) - is a callback function which will be called when message with above idx.val will be received by connector core. Using connector completely hides low-level transport layer from it's users. Connector uses new netlink ability to have many groups in one socket. [ Incorporating many cleanups and fixes by myself and Andrew Morton -DaveM ] Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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