linux/include/xen/xenbus.h

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/******************************************************************************
* xenbus.h
*
* Talks to Xen Store to figure out what devices we have.
*
* Copyright (C) 2005 Rusty Russell, IBM Corporation
* Copyright (C) 2005 XenSource Ltd.
*
* 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; or, when distributed
* separately from the Linux kernel or incorporated into other
* software packages, subject to the following license:
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this source file (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software,
* and to permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*/
#ifndef _XEN_XENBUS_H
#define _XEN_XENBUS_H
#include <linux/device.h>
#include <linux/notifier.h>
#include <linux/mutex.h>
#include <linux/export.h>
#include <linux/completion.h>
#include <linux/init.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 09:04:11 +01:00
#include <linux/slab.h>
#include <xen/interface/xen.h>
#include <xen/interface/grant_table.h>
#include <xen/interface/io/xenbus.h>
#include <xen/interface/io/xs_wire.h>
/* Register callback to watch this node. */
struct xenbus_watch
{
struct list_head list;
/* Path being watched. */
const char *node;
/* Callback (executed in a process context with no locks held). */
void (*callback)(struct xenbus_watch *,
const char **vec, unsigned int len);
};
/* A xenbus device. */
struct xenbus_device {
const char *devicetype;
const char *nodename;
const char *otherend;
int otherend_id;
struct xenbus_watch otherend_watch;
struct device dev;
enum xenbus_state state;
struct completion down;
};
static inline struct xenbus_device *to_xenbus_device(struct device *dev)
{
return container_of(dev, struct xenbus_device, dev);
}
struct xenbus_device_id
{
/* .../device/<device_type>/<identifier> */
char devicetype[32]; /* General class of device. */
};
/* A xenbus driver. */
struct xenbus_driver {
const struct xenbus_device_id *ids;
int (*probe)(struct xenbus_device *dev,
const struct xenbus_device_id *id);
void (*otherend_changed)(struct xenbus_device *dev,
enum xenbus_state backend_state);
int (*remove)(struct xenbus_device *dev);
int (*suspend)(struct xenbus_device *dev);
int (*resume)(struct xenbus_device *dev);
int (*uevent)(struct xenbus_device *, struct kobj_uevent_env *);
struct device_driver driver;
int (*read_otherend_details)(struct xenbus_device *dev);
int (*is_ready)(struct xenbus_device *dev);
};
#define DEFINE_XENBUS_DRIVER(var, drvname, methods...) \
struct xenbus_driver var ## _driver = { \
.driver.name = drvname + 0 ?: var ## _ids->devicetype, \
.driver.owner = THIS_MODULE, \
.ids = var ## _ids, ## methods \
}
static inline struct xenbus_driver *to_xenbus_driver(struct device_driver *drv)
{
return container_of(drv, struct xenbus_driver, driver);
}
int __must_check xenbus_register_frontend(struct xenbus_driver *);
int __must_check xenbus_register_backend(struct xenbus_driver *);
void xenbus_unregister_driver(struct xenbus_driver *drv);
struct xenbus_transaction
{
u32 id;
};
/* Nil transaction ID. */
#define XBT_NIL ((struct xenbus_transaction) { 0 })
char **xenbus_directory(struct xenbus_transaction t,
const char *dir, const char *node, unsigned int *num);
void *xenbus_read(struct xenbus_transaction t,
const char *dir, const char *node, unsigned int *len);
int xenbus_write(struct xenbus_transaction t,
const char *dir, const char *node, const char *string);
int xenbus_mkdir(struct xenbus_transaction t,
const char *dir, const char *node);
int xenbus_exists(struct xenbus_transaction t,
const char *dir, const char *node);
int xenbus_rm(struct xenbus_transaction t, const char *dir, const char *node);
int xenbus_transaction_start(struct xenbus_transaction *t);
int xenbus_transaction_end(struct xenbus_transaction t, int abort);
/* Single read and scanf: returns -errno or num scanned if > 0. */
int xenbus_scanf(struct xenbus_transaction t,
const char *dir, const char *node, const char *fmt, ...)
__attribute__((format(scanf, 4, 5)));
/* Single printf and write: returns -errno or 0. */
__printf(4, 5)
int xenbus_printf(struct xenbus_transaction t,
const char *dir, const char *node, const char *fmt, ...);
/* Generic read function: NULL-terminated triples of name,
* sprintf-style type string, and pointer. Returns 0 or errno.*/
int xenbus_gather(struct xenbus_transaction t, const char *dir, ...);
/* notifer routines for when the xenstore comes up */
extern int xenstored_ready;
int register_xenstore_notifier(struct notifier_block *nb);
void unregister_xenstore_notifier(struct notifier_block *nb);
int register_xenbus_watch(struct xenbus_watch *watch);
void unregister_xenbus_watch(struct xenbus_watch *watch);
void xs_suspend(void);
void xs_resume(void);
void xs_suspend_cancel(void);
/* Used by xenbus_dev to borrow kernel's store connection. */
void *xenbus_dev_request_and_reply(struct xsd_sockmsg *msg);
struct work_struct;
/* Prepare for domain suspend: then resume or cancel the suspend. */
void xenbus_suspend(void);
void xenbus_resume(void);
void xenbus_probe(struct work_struct *);
void xenbus_suspend_cancel(void);
#define XENBUS_IS_ERR_READ(str) ({ \
if (!IS_ERR(str) && strlen(str) == 0) { \
kfree(str); \
str = ERR_PTR(-ERANGE); \
} \
IS_ERR(str); \
})
#define XENBUS_EXIST_ERR(err) ((err) == -ENOENT || (err) == -ERANGE)
int xenbus_watch_path(struct xenbus_device *dev, const char *path,
struct xenbus_watch *watch,
void (*callback)(struct xenbus_watch *,
const char **, unsigned int));
__printf(4, 5)
int xenbus_watch_pathfmt(struct xenbus_device *dev, struct xenbus_watch *watch,
void (*callback)(struct xenbus_watch *,
const char **, unsigned int),
const char *pathfmt, ...);
int xenbus_switch_state(struct xenbus_device *dev, enum xenbus_state new_state);
int xenbus_grant_ring(struct xenbus_device *dev, unsigned long ring_mfn);
int xenbus_map_ring_valloc(struct xenbus_device *dev,
int gnt_ref, void **vaddr);
int xenbus_map_ring(struct xenbus_device *dev, int gnt_ref,
grant_handle_t *handle, void *vaddr);
int xenbus_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr);
int xenbus_unmap_ring(struct xenbus_device *dev,
grant_handle_t handle, void *vaddr);
int xenbus_alloc_evtchn(struct xenbus_device *dev, int *port);
int xenbus_bind_evtchn(struct xenbus_device *dev, int remote_port, int *port);
int xenbus_free_evtchn(struct xenbus_device *dev, int port);
enum xenbus_state xenbus_read_driver_state(const char *path);
__printf(3, 4)
void xenbus_dev_error(struct xenbus_device *dev, int err, const char *fmt, ...);
__printf(3, 4)
void xenbus_dev_fatal(struct xenbus_device *dev, int err, const char *fmt, ...);
const char *xenbus_strstate(enum xenbus_state state);
int xenbus_dev_is_online(struct xenbus_device *dev);
int xenbus_frontend_closed(struct xenbus_device *dev);
#endif /* _XEN_XENBUS_H */