linux/net/tipc/core.h

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/*
* net/tipc/core.h: Include file for TIPC global declarations
*
tipc: introduce new TIPC server infrastructure TIPC has two internal servers, one providing a subscription service for topology events, and another providing the configuration interface. These servers have previously been running in BH context, accessing the TIPC-port (aka native) API directly. Apart from these servers, even the TIPC socket implementation is partially built on this API. As this API may simultaneously be called via different paths and in different contexts, a complex and costly lock policiy is required in order to protect TIPC internal resources. To eliminate the need for this complex lock policiy, we introduce a new, generic service API that uses kernel sockets for message passing instead of the native API. Once the toplogy and configuration servers are converted to use this new service, all code pertaining to the native API can be removed. This entails a significant reduction in code amount and complexity, and opens up for a complete rework of the locking policy in TIPC. The new service also solves another problem: As the current topology server works in BH context, it cannot easily be blocked when sending of events fails due to congestion. In such cases events may have to be silently dropped, something that is unacceptable. Therefore, the new service keeps a dedicated outbound queue receiving messages from BH context. Once messages are inserted into this queue, we will immediately schedule a work from a special workqueue. This way, messages/events from the topology server are in reality sent in process context, and the server can block if necessary. Analogously, there is a new workqueue for receiving messages. Once a notification about an arriving message is received in BH context, we schedule a work from the receive workqueue to do the job of receiving the message in process context. As both sending and receive messages are now finished in processes, subscribed events cannot be dropped any more. As of this commit, this new server infrastructure is built, but not actually yet called by the existing TIPC code, but since the conversion changes required in order to use it are significant, the addition is kept here as a separate commit. Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17 14:54:39 +00:00
* Copyright (c) 2005-2006, 2013 Ericsson AB
* Copyright (c) 2005-2007, 2010-2013, Wind River Systems
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the names of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL") version 2 as published by the Free
* Software Foundation.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _TIPC_CORE_H
#define _TIPC_CORE_H
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/tipc.h>
#include <linux/tipc_config.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/mm.h>
#include <linux/timer.h>
#include <linux/string.h>
#include <linux/uaccess.h>
#include <linux/interrupt.h>
#include <linux/atomic.h>
#include <asm/hardirq.h>
#include <linux/netdevice.h>
#include <linux/in.h>
#include <linux/list.h>
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>
2010-03-24 08:04:11 +00:00
#include <linux/slab.h>
#include <linux/vmalloc.h>
#define TIPC_MOD_VER "2.0.0"
#define ULTRA_STRING_MAX_LEN 32768
#define TIPC_MAX_SUBSCRIPTIONS 65535
#define TIPC_MAX_PUBLICATIONS 65535
tipc: phase out most of the struct print_buf usage The tipc_printf is renamed to tipc_snprintf, as the new name describes more what the function actually does. It is also changed to take a buffer and length parameter and return number of characters written to the buffer. All callers of this function that used to pass a print_buf are updated. Final removal of the struct print_buf itself will be done synchronously with the pending removal of the deprecated logging code that also was using it. Functions that build up a response message with a list of ports, nametable contents etc. are changed to return the number of characters written to the output buffer. This information was previously hidden in a field of the print_buf struct, and the number of chars written was fetched with a call to tipc_printbuf_validate. This function is removed since it is no longer referenced nor needed. A generic max size ULTRA_STRING_MAX_LEN is defined, named in keeping with the existing TIPC_TLV_ULTRA_STRING, and the various definitions in port, link and nametable code that largely duplicated this information are removed. This means that amount of link statistics that can be returned is now increased from 2k to 32k. The buffer overflow check is now done just before the reply message is passed over netlink or TIPC to a remote node and the message indicating a truncated buffer is changed to a less dramatic one (less CAPS), placed at the end of the message. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-06-29 04:50:23 +00:00
struct tipc_msg; /* msg.h */
tipc: phase out most of the struct print_buf usage The tipc_printf is renamed to tipc_snprintf, as the new name describes more what the function actually does. It is also changed to take a buffer and length parameter and return number of characters written to the buffer. All callers of this function that used to pass a print_buf are updated. Final removal of the struct print_buf itself will be done synchronously with the pending removal of the deprecated logging code that also was using it. Functions that build up a response message with a list of ports, nametable contents etc. are changed to return the number of characters written to the output buffer. This information was previously hidden in a field of the print_buf struct, and the number of chars written was fetched with a call to tipc_printbuf_validate. This function is removed since it is no longer referenced nor needed. A generic max size ULTRA_STRING_MAX_LEN is defined, named in keeping with the existing TIPC_TLV_ULTRA_STRING, and the various definitions in port, link and nametable code that largely duplicated this information are removed. This means that amount of link statistics that can be returned is now increased from 2k to 32k. The buffer overflow check is now done just before the reply message is passed over netlink or TIPC to a remote node and the message indicating a truncated buffer is changed to a less dramatic one (less CAPS), placed at the end of the message. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-06-29 04:50:23 +00:00
int tipc_snprintf(char *buf, int len, const char *fmt, ...);
/*
* TIPC-specific error codes
*/
#define ELINKCONG EAGAIN /* link congestion <=> resource unavailable */
/*
* Global configuration variables
*/
extern u32 tipc_own_addr __read_mostly;
extern int tipc_max_ports __read_mostly;
extern int tipc_net_id __read_mostly;
extern int tipc_remote_management __read_mostly;
extern int sysctl_tipc_rmem[3] __read_mostly;
/*
* Other global variables
*/
extern int tipc_random __read_mostly;
/*
* Routines available to privileged subsystems
*/
int tipc_core_start_net(unsigned long);
int tipc_handler_start(void);
void tipc_handler_stop(void);
int tipc_netlink_start(void);
void tipc_netlink_stop(void);
int tipc_socket_init(void);
void tipc_socket_stop(void);
int tipc_sock_create_local(int type, struct socket **res);
void tipc_sock_release_local(struct socket *sock);
int tipc_sock_accept_local(struct socket *sock, struct socket **newsock,
int flags);
#ifdef CONFIG_SYSCTL
int tipc_register_sysctl(void);
void tipc_unregister_sysctl(void);
#else
#define tipc_register_sysctl() 0
#define tipc_unregister_sysctl()
#endif
/*
* TIPC timer and signal code
*/
typedef void (*Handler) (unsigned long);
u32 tipc_k_signal(Handler routine, unsigned long argument);
/**
* k_init_timer - initialize a timer
* @timer: pointer to timer structure
* @routine: pointer to routine to invoke when timer expires
* @argument: value to pass to routine when timer expires
*
* Timer must be initialized before use (and terminated when no longer needed).
*/
static inline void k_init_timer(struct timer_list *timer, Handler routine,
unsigned long argument)
{
setup_timer(timer, routine, argument);
}
/**
* k_start_timer - start a timer
* @timer: pointer to timer structure
* @msec: time to delay (in ms)
*
* Schedules a previously initialized timer for later execution.
* If timer is already running, the new timeout overrides the previous request.
*
* To ensure the timer doesn't expire before the specified delay elapses,
* the amount of delay is rounded up when converting to the jiffies
* then an additional jiffy is added to account for the fact that
* the starting time may be in the middle of the current jiffy.
*/
static inline void k_start_timer(struct timer_list *timer, unsigned long msec)
{
mod_timer(timer, jiffies + msecs_to_jiffies(msec) + 1);
}
/**
* k_cancel_timer - cancel a timer
* @timer: pointer to timer structure
*
* Cancels a previously initialized timer.
* Can be called safely even if the timer is already inactive.
*
* WARNING: Must not be called when holding locks required by the timer's
* timeout routine, otherwise deadlock can occur on SMP systems!
*/
static inline void k_cancel_timer(struct timer_list *timer)
{
del_timer_sync(timer);
}
/**
* k_term_timer - terminate a timer
* @timer: pointer to timer structure
*
* Prevents further use of a previously initialized timer.
*
* WARNING: Caller must ensure timer isn't currently running.
*
* (Do not "enhance" this routine to automatically cancel an active timer,
* otherwise deadlock can arise when a timeout routine calls k_term_timer.)
*/
static inline void k_term_timer(struct timer_list *timer)
{
}
/*
* TIPC message buffer code
*
* TIPC message buffer headroom reserves space for the worst-case
* link-level device header (in case the message is sent off-node).
*
* Note: Headroom should be a multiple of 4 to ensure the TIPC header fields
* are word aligned for quicker access
*/
#define BUF_HEADROOM LL_MAX_HEADER
struct tipc_skb_cb {
void *handle;
};
#define TIPC_SKB_CB(__skb) ((struct tipc_skb_cb *)&((__skb)->cb[0]))
static inline struct tipc_msg *buf_msg(struct sk_buff *skb)
{
return (struct tipc_msg *)skb->data;
}
struct sk_buff *tipc_buf_acquire(u32 size);
#endif