linux/drivers/misc/sgi-xp/xp_main.c
Kees Cook 234041dfe5 sgi-xp: Use designated initializers
Prepare to mark sensitive kernel structures for randomization by making
sure they're using designated initializers. In this case, no initializers
are needed (they can be NULL initialized and callers adjusted to check
for NULL, which is more efficient than an indirect call).

Cc: Robin Holt <robinmholt@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Christoph Hellwig <hch@infradead.org>
2017-05-28 10:22:42 -07:00

265 lines
7.0 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (c) 2004-2008 Silicon Graphics, Inc. All Rights Reserved.
*/
/*
* Cross Partition (XP) base.
*
* XP provides a base from which its users can interact
* with XPC, yet not be dependent on XPC.
*
*/
#include <linux/module.h>
#include <linux/device.h>
#include "xp.h"
/* define the XP debug device structures to be used with dev_dbg() et al */
struct device_driver xp_dbg_name = {
.name = "xp"
};
struct device xp_dbg_subname = {
.init_name = "", /* set to "" */
.driver = &xp_dbg_name
};
struct device *xp = &xp_dbg_subname;
/* max #of partitions possible */
short xp_max_npartitions;
EXPORT_SYMBOL_GPL(xp_max_npartitions);
short xp_partition_id;
EXPORT_SYMBOL_GPL(xp_partition_id);
u8 xp_region_size;
EXPORT_SYMBOL_GPL(xp_region_size);
unsigned long (*xp_pa) (void *addr);
EXPORT_SYMBOL_GPL(xp_pa);
unsigned long (*xp_socket_pa) (unsigned long gpa);
EXPORT_SYMBOL_GPL(xp_socket_pa);
enum xp_retval (*xp_remote_memcpy) (unsigned long dst_gpa,
const unsigned long src_gpa, size_t len);
EXPORT_SYMBOL_GPL(xp_remote_memcpy);
int (*xp_cpu_to_nasid) (int cpuid);
EXPORT_SYMBOL_GPL(xp_cpu_to_nasid);
enum xp_retval (*xp_expand_memprotect) (unsigned long phys_addr,
unsigned long size);
EXPORT_SYMBOL_GPL(xp_expand_memprotect);
enum xp_retval (*xp_restrict_memprotect) (unsigned long phys_addr,
unsigned long size);
EXPORT_SYMBOL_GPL(xp_restrict_memprotect);
/*
* xpc_registrations[] keeps track of xpc_connect()'s done by the kernel-level
* users of XPC.
*/
struct xpc_registration xpc_registrations[XPC_MAX_NCHANNELS];
EXPORT_SYMBOL_GPL(xpc_registrations);
/*
* Initialize the XPC interface to NULL to indicate that XPC isn't loaded.
*/
struct xpc_interface xpc_interface = { };
EXPORT_SYMBOL_GPL(xpc_interface);
/*
* XPC calls this when it (the XPC module) has been loaded.
*/
void
xpc_set_interface(void (*connect) (int),
void (*disconnect) (int),
enum xp_retval (*send) (short, int, u32, void *, u16),
enum xp_retval (*send_notify) (short, int, u32, void *, u16,
xpc_notify_func, void *),
void (*received) (short, int, void *),
enum xp_retval (*partid_to_nasids) (short, void *))
{
xpc_interface.connect = connect;
xpc_interface.disconnect = disconnect;
xpc_interface.send = send;
xpc_interface.send_notify = send_notify;
xpc_interface.received = received;
xpc_interface.partid_to_nasids = partid_to_nasids;
}
EXPORT_SYMBOL_GPL(xpc_set_interface);
/*
* XPC calls this when it (the XPC module) is being unloaded.
*/
void
xpc_clear_interface(void)
{
memset(&xpc_interface, 0, sizeof(xpc_interface));
}
EXPORT_SYMBOL_GPL(xpc_clear_interface);
/*
* Register for automatic establishment of a channel connection whenever
* a partition comes up.
*
* Arguments:
*
* ch_number - channel # to register for connection.
* func - function to call for asynchronous notification of channel
* state changes (i.e., connection, disconnection, error) and
* the arrival of incoming messages.
* key - pointer to optional user-defined value that gets passed back
* to the user on any callouts made to func.
* payload_size - size in bytes of the XPC message's payload area which
* contains a user-defined message. The user should make
* this large enough to hold their largest message.
* nentries - max #of XPC message entries a message queue can contain.
* The actual number, which is determined when a connection
* is established and may be less then requested, will be
* passed to the user via the xpConnected callout.
* assigned_limit - max number of kthreads allowed to be processing
* messages (per connection) at any given instant.
* idle_limit - max number of kthreads allowed to be idle at any given
* instant.
*/
enum xp_retval
xpc_connect(int ch_number, xpc_channel_func func, void *key, u16 payload_size,
u16 nentries, u32 assigned_limit, u32 idle_limit)
{
struct xpc_registration *registration;
DBUG_ON(ch_number < 0 || ch_number >= XPC_MAX_NCHANNELS);
DBUG_ON(payload_size == 0 || nentries == 0);
DBUG_ON(func == NULL);
DBUG_ON(assigned_limit == 0 || idle_limit > assigned_limit);
if (XPC_MSG_SIZE(payload_size) > XPC_MSG_MAX_SIZE)
return xpPayloadTooBig;
registration = &xpc_registrations[ch_number];
if (mutex_lock_interruptible(&registration->mutex) != 0)
return xpInterrupted;
/* if XPC_CHANNEL_REGISTERED(ch_number) */
if (registration->func != NULL) {
mutex_unlock(&registration->mutex);
return xpAlreadyRegistered;
}
/* register the channel for connection */
registration->entry_size = XPC_MSG_SIZE(payload_size);
registration->nentries = nentries;
registration->assigned_limit = assigned_limit;
registration->idle_limit = idle_limit;
registration->key = key;
registration->func = func;
mutex_unlock(&registration->mutex);
if (xpc_interface.connect)
xpc_interface.connect(ch_number);
return xpSuccess;
}
EXPORT_SYMBOL_GPL(xpc_connect);
/*
* Remove the registration for automatic connection of the specified channel
* when a partition comes up.
*
* Before returning this xpc_disconnect() will wait for all connections on the
* specified channel have been closed/torndown. So the caller can be assured
* that they will not be receiving any more callouts from XPC to their
* function registered via xpc_connect().
*
* Arguments:
*
* ch_number - channel # to unregister.
*/
void
xpc_disconnect(int ch_number)
{
struct xpc_registration *registration;
DBUG_ON(ch_number < 0 || ch_number >= XPC_MAX_NCHANNELS);
registration = &xpc_registrations[ch_number];
/*
* We've decided not to make this a down_interruptible(), since we
* figured XPC's users will just turn around and call xpc_disconnect()
* again anyways, so we might as well wait, if need be.
*/
mutex_lock(&registration->mutex);
/* if !XPC_CHANNEL_REGISTERED(ch_number) */
if (registration->func == NULL) {
mutex_unlock(&registration->mutex);
return;
}
/* remove the connection registration for the specified channel */
registration->func = NULL;
registration->key = NULL;
registration->nentries = 0;
registration->entry_size = 0;
registration->assigned_limit = 0;
registration->idle_limit = 0;
if (xpc_interface.disconnect)
xpc_interface.disconnect(ch_number);
mutex_unlock(&registration->mutex);
return;
}
EXPORT_SYMBOL_GPL(xpc_disconnect);
int __init
xp_init(void)
{
enum xp_retval ret;
int ch_number;
/* initialize the connection registration mutex */
for (ch_number = 0; ch_number < XPC_MAX_NCHANNELS; ch_number++)
mutex_init(&xpc_registrations[ch_number].mutex);
if (is_shub())
ret = xp_init_sn2();
else if (is_uv())
ret = xp_init_uv();
else
ret = 0;
if (ret != xpSuccess)
return ret;
return 0;
}
module_init(xp_init);
void __exit
xp_exit(void)
{
if (is_shub())
xp_exit_sn2();
else if (is_uv())
xp_exit_uv();
}
module_exit(xp_exit);
MODULE_AUTHOR("Silicon Graphics, Inc.");
MODULE_DESCRIPTION("Cross Partition (XP) base");
MODULE_LICENSE("GPL");