linux/drivers/misc/ibmasm/ibmasm.h
Max Asbock 8818760512 [PATCH] ibmasm driver: fix race in command refcount logic
This patch fixes a race in the command reference counting logic by putting
spinlocks around kobject_put() in the command_put function.

- Also added debug messages.

- Changed a memcpy to memcpy_fromio since we are reading from io space.

Signed-off-by: Max Asbock <masbock@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21 19:07:35 -07:00

220 lines
6.7 KiB
C

/*
* IBM ASM Service Processor Device Driver
*
* This program 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.
*
* Copyright (C) IBM Corporation, 2004
*
* Author: Max Asböck <amax@us.ibm.com>
*
*/
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/list.h>
#include <linux/wait.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/config.h>
#include <linux/module.h>
#include <linux/version.h>
#include <linux/interrupt.h>
#include <linux/device.h>
#include <linux/input.h>
/* Driver identification */
#define DRIVER_NAME "ibmasm"
#define DRIVER_VERSION "1.0"
#define DRIVER_AUTHOR "Max Asbock <masbock@us.ibm.com>, Vernon Mauery <vernux@us.ibm.com>"
#define DRIVER_DESC "IBM ASM Service Processor Driver"
#define err(msg) printk(KERN_ERR "%s: " msg "\n", DRIVER_NAME)
#define info(msg) printk(KERN_INFO "%s: " msg "\n", DRIVER_NAME)
extern int ibmasm_debug;
#define dbg(STR, ARGS...) \
do { \
if (ibmasm_debug) \
printk(KERN_DEBUG STR , ##ARGS); \
} while (0)
static inline char *get_timestamp(char *buf)
{
struct timeval now;
do_gettimeofday(&now);
sprintf(buf, "%lu.%lu", now.tv_sec, now.tv_usec);
return buf;
}
#define IBMASM_CMD_PENDING 0
#define IBMASM_CMD_COMPLETE 1
#define IBMASM_CMD_FAILED 2
#define IBMASM_CMD_TIMEOUT_NORMAL 45
#define IBMASM_CMD_TIMEOUT_EXTRA 240
#define IBMASM_CMD_MAX_BUFFER_SIZE 0x8000
#define REVERSE_HEARTBEAT_TIMEOUT 120
#define HEARTBEAT_BUFFER_SIZE 0x400
#ifdef IA64
#define IBMASM_DRIVER_VPD "Lin64 6.08 "
#else
#define IBMASM_DRIVER_VPD "Lin32 6.08 "
#endif
#define SYSTEM_STATE_OS_UP 5
#define SYSTEM_STATE_OS_DOWN 4
#define IBMASM_NAME_SIZE 16
#define IBMASM_NUM_EVENTS 10
#define IBMASM_EVENT_MAX_SIZE 2048u
struct command {
struct list_head queue_node;
wait_queue_head_t wait;
unsigned char *buffer;
size_t buffer_size;
int status;
struct kobject kobj;
spinlock_t *lock;
};
#define to_command(c) container_of(c, struct command, kobj)
static inline void command_put(struct command *cmd)
{
unsigned long flags;
spin_lock_irqsave(cmd->lock, flags);
kobject_put(&cmd->kobj);
spin_unlock_irqrestore(cmd->lock, flags);
}
static inline void command_get(struct command *cmd)
{
kobject_get(&cmd->kobj);
}
struct ibmasm_event {
unsigned int serial_number;
unsigned int data_size;
unsigned char data[IBMASM_EVENT_MAX_SIZE];
};
struct event_buffer {
struct ibmasm_event events[IBMASM_NUM_EVENTS];
unsigned int next_serial_number;
unsigned int next_index;
struct list_head readers;
};
struct event_reader {
int cancelled;
unsigned int next_serial_number;
wait_queue_head_t wait;
struct list_head node;
unsigned int data_size;
unsigned char data[IBMASM_EVENT_MAX_SIZE];
};
struct reverse_heartbeat {
wait_queue_head_t wait;
unsigned int stopped;
};
struct ibmasm_remote {
struct input_dev keybd_dev;
struct input_dev mouse_dev;
};
struct service_processor {
struct list_head node;
spinlock_t lock;
void __iomem *base_address;
unsigned int irq;
struct command *current_command;
struct command *heartbeat;
struct list_head command_queue;
struct event_buffer *event_buffer;
char dirname[IBMASM_NAME_SIZE];
char devname[IBMASM_NAME_SIZE];
unsigned int number;
struct ibmasm_remote *remote;
int serial_line;
struct device *dev;
};
/* command processing */
extern struct command *ibmasm_new_command(struct service_processor *sp, size_t buffer_size);
extern void ibmasm_exec_command(struct service_processor *sp, struct command *cmd);
extern void ibmasm_wait_for_response(struct command *cmd, int timeout);
extern void ibmasm_receive_command_response(struct service_processor *sp, void *response, size_t size);
/* event processing */
extern int ibmasm_event_buffer_init(struct service_processor *sp);
extern void ibmasm_event_buffer_exit(struct service_processor *sp);
extern void ibmasm_receive_event(struct service_processor *sp, void *data, unsigned int data_size);
extern void ibmasm_event_reader_register(struct service_processor *sp, struct event_reader *reader);
extern void ibmasm_event_reader_unregister(struct service_processor *sp, struct event_reader *reader);
extern int ibmasm_get_next_event(struct service_processor *sp, struct event_reader *reader);
extern void ibmasm_cancel_next_event(struct event_reader *reader);
/* heartbeat - from SP to OS */
extern void ibmasm_register_panic_notifier(void);
extern void ibmasm_unregister_panic_notifier(void);
extern int ibmasm_heartbeat_init(struct service_processor *sp);
extern void ibmasm_heartbeat_exit(struct service_processor *sp);
extern void ibmasm_receive_heartbeat(struct service_processor *sp, void *message, size_t size);
/* reverse heartbeat - from OS to SP */
extern void ibmasm_init_reverse_heartbeat(struct service_processor *sp, struct reverse_heartbeat *rhb);
extern int ibmasm_start_reverse_heartbeat(struct service_processor *sp, struct reverse_heartbeat *rhb);
extern void ibmasm_stop_reverse_heartbeat(struct reverse_heartbeat *rhb);
/* dot commands */
extern void ibmasm_receive_message(struct service_processor *sp, void *data, int data_size);
extern int ibmasm_send_driver_vpd(struct service_processor *sp);
extern int ibmasm_send_os_state(struct service_processor *sp, int os_state);
/* low level message processing */
extern int ibmasm_send_i2o_message(struct service_processor *sp);
extern irqreturn_t ibmasm_interrupt_handler(int irq, void * dev_id, struct pt_regs *regs);
/* remote console */
extern void ibmasm_handle_mouse_interrupt(struct service_processor *sp, struct pt_regs *regs);
extern int ibmasm_init_remote_input_dev(struct service_processor *sp);
extern void ibmasm_free_remote_input_dev(struct service_processor *sp);
/* file system */
extern int ibmasmfs_register(void);
extern void ibmasmfs_unregister(void);
extern void ibmasmfs_add_sp(struct service_processor *sp);
/* uart */
#ifdef CONFIG_SERIAL_8250
extern void ibmasm_register_uart(struct service_processor *sp);
extern void ibmasm_unregister_uart(struct service_processor *sp);
#else
#define ibmasm_register_uart(sp) do { } while(0)
#define ibmasm_unregister_uart(sp) do { } while(0)
#endif