rtas_flash.c

linux-2.4.29操作系统的源码

			wait_time = rtas_extended_busy_delay_time(rc);
			udelay(wait_time * 1000);
		} else
			break;
	}

	args_buf->status = rc;
}

static ssize_t manage_flash_read(struct file *file, char *buf,
			       size_t count, loff_t *ppos)
{
	struct proc_dir_entry *dp = file->f_dentry->d_inode->u.generic_ip;
	struct rtas_manage_flash_t *args_buf;
	char msg[RTAS_MSG_MAXLEN];
	int msglen;
	int error;

	args_buf = (struct rtas_manage_flash_t *) dp->data;
	if (args_buf == NULL)
		return 0;

	msglen = sprintf(msg, "%d\n", args_buf->status);
	if (msglen > count)
		msglen = count;

	if (ppos && *ppos != 0)
		return 0;	/* be cheap */

	error = verify_area(VERIFY_WRITE, buf, msglen);
	if (error)
		return -EINVAL;

	if (copy_to_user(buf, msg, msglen))
		return -EFAULT;

	if (ppos)
		*ppos = msglen;
	return msglen;
}

static ssize_t manage_flash_write(struct file *file, const char *buf,
				size_t count, loff_t *off)
{
	struct proc_dir_entry *dp = file->f_dentry->d_inode->u.generic_ip;
	struct rtas_manage_flash_t *args_buf;
	const char reject_str[] = "0";
	const char commit_str[] = "1";
	char stkbuf[10];
	int op;

	args_buf = (struct rtas_manage_flash_t *) dp->data;
	if ((args_buf->status == MANAGE_AUTH) || (count == 0))
		return count;

	op = -1;
	if (buf) {
		if (count > 9) count = 9;
		if (copy_from_user (stkbuf, buf, count)) {
			return -EFAULT;
		}
		if (strncmp(stkbuf, reject_str, strlen(reject_str)) == 0)
			op = RTAS_REJECT_TMP_IMG;
		else if (strncmp(stkbuf, commit_str, strlen(commit_str)) == 0)
			op = RTAS_COMMIT_TMP_IMG;
	}

	if (op == -1)   /* buf is empty, or contains invalid string */
		return -EINVAL;

	args_buf->op = op;
	manage_flash(args_buf);

	return count;
}

static void validate_flash(struct rtas_validate_flash_t *args_buf)
{
	int token = rtas_token("ibm,validate-flash-image");
	unsigned int wait_time;
	long update_results;
	s32 rc;

	rc = 0;
	while(1) {
		spin_lock(&rtas_data_buf_lock);
		memcpy(rtas_data_buf, args_buf->buf, VALIDATE_BUF_SIZE);
		rc = (s32) rtas_call(token, 2, 2, &update_results,
				     __pa(rtas_data_buf), args_buf->buf_size);
		memcpy(args_buf->buf, rtas_data_buf, VALIDATE_BUF_SIZE);
		spin_unlock(&rtas_data_buf_lock);

		if (rc == RTAS_RC_BUSY)
			udelay(1);
		else if (rtas_is_extended_busy(rc)) {
			wait_time = rtas_extended_busy_delay_time(rc);
			udelay(wait_time * 1000);
		} else
			break;
	}

	args_buf->status = rc;
	args_buf->update_results = (u32) update_results;
}

static int get_validate_flash_msg(struct rtas_validate_flash_t *args_buf,
				   char *msg)
{
	int n;

	if (args_buf->status >= VALIDATE_TMP_UPDATE) {
		n = sprintf(msg, "%d\n", args_buf->update_results);
		if ((args_buf->update_results >= VALIDATE_CUR_UNKNOWN) ||
		    (args_buf->update_results == VALIDATE_TMP_UPDATE))
			n += sprintf(msg + n, "%s\n", args_buf->buf);
	} else {
		n = sprintf(msg, "%d\n", args_buf->status);
	}
	return n;
}

static ssize_t validate_flash_read(struct file *file, char *buf,
			       size_t count, loff_t *ppos)
{
	struct proc_dir_entry *dp = file->f_dentry->d_inode->u.generic_ip;
	struct rtas_validate_flash_t *args_buf;
	char msg[RTAS_MSG_MAXLEN];
	int msglen;
	int error;

	args_buf = (struct rtas_validate_flash_t *) dp->data;

	if (ppos && *ppos != 0)
		return 0;	/* be cheap */

	msglen = get_validate_flash_msg(args_buf, msg);
	if (msglen > count)
		msglen = count;

	error = verify_area(VERIFY_WRITE, buf, msglen);
	if (error)
		return -EINVAL;

	if (copy_to_user(buf, msg, msglen))
		return -EFAULT;

	if (ppos)
		*ppos = msglen;
	return msglen;
}

static ssize_t validate_flash_write(struct file *file, const char *buf,
				size_t count, loff_t *off)
{
	struct proc_dir_entry *dp = file->f_dentry->d_inode->u.generic_ip;
	struct rtas_validate_flash_t *args_buf;
	int rc;

	args_buf = (struct rtas_validate_flash_t *) dp->data;

	if (dp->data == NULL) {
		dp->data = kmalloc(sizeof(struct rtas_validate_flash_t),
				GFP_KERNEL);
		if (dp->data == NULL)
			return -ENOMEM;
	}

	/* We are only interested in the first 4K of the
	 * candidate image */
	if ((*off >= VALIDATE_BUF_SIZE) ||
		(args_buf->status == VALIDATE_AUTH)) {
		*off += count;
		return count;
	}

	if (*off + count >= VALIDATE_BUF_SIZE)  {
		count = VALIDATE_BUF_SIZE - *off;
		args_buf->status = VALIDATE_READY;
	} else {
		args_buf->status = VALIDATE_INCOMPLETE;
	}

	if (verify_area(VERIFY_READ, buf, count)) {
		rc = -EFAULT;
		goto done;
	}
	if (copy_from_user(args_buf->buf + *off, buf, count)) {
		rc = -EFAULT;
		goto done;
	}

	*off += count;
	rc = count;
done:
	if (rc < 0) {
		kfree(dp->data);
		dp->data = NULL;
	}
	return rc;
}

static int validate_flash_release(struct inode *inode, struct file *file)
{
	struct proc_dir_entry *dp = file->f_dentry->d_inode->u.generic_ip;
	struct rtas_validate_flash_t *args_buf;

	args_buf = (struct rtas_validate_flash_t *) dp->data;

	if (args_buf->status == VALIDATE_READY) {
		args_buf->buf_size = VALIDATE_BUF_SIZE;
		validate_flash(args_buf);
	}

	atomic_dec(&dp->count);

	return 0;
}

static inline void remove_flash_pde(struct proc_dir_entry *dp)
{
	if (dp) {
		if (dp->data != NULL)
			kfree(dp->data);
		remove_proc_entry(dp->name, rtas_proc_dir);
	}
}

static inline int initialize_flash_pde_data(const char *rtas_call_name,
					    size_t buf_size,
					    struct proc_dir_entry *dp)
{
	int *status;
	int token;

	dp->data = kmalloc(buf_size, GFP_KERNEL);
	if (dp->data == NULL) {
		remove_flash_pde(dp);
		return -ENOMEM;
	}

	memset(dp->data, 0, buf_size);

	/* This code assumes that the status int is the first member of the
	 * struct
	 */
	status = (int *) dp->data;
	token = rtas_token(rtas_call_name);
	if (token == RTAS_UNKNOWN_SERVICE)
		*status = FLASH_AUTH;
	else
		*status = FLASH_NO_OP;

	return 0;
}

static inline struct proc_dir_entry * create_flash_pde(const char *filename,
					struct file_operations *fops)
{
	struct proc_dir_entry *ent = NULL;

	ent = create_proc_entry(filename, S_IRUSR | S_IWUSR, rtas_proc_dir);
	if (ent != NULL) {
		ent->nlink = 1;
		ent->proc_fops = fops;
		ent->owner = THIS_MODULE;
	}

	return ent;
}

static struct file_operations rtas_flash_operations = {
	read:		rtas_flash_read,
	write:		rtas_flash_write,
	open:		rtas_excl_open,
	release:	rtas_flash_release,
};

static struct file_operations manage_flash_operations = {
	read:		manage_flash_read,
	write:		manage_flash_write,
	open:		rtas_excl_open,
	release:	rtas_excl_release,
};

static struct file_operations validate_flash_operations = {
	read:		validate_flash_read,
	write:		validate_flash_write,
	open:		rtas_excl_open,
	release:	validate_flash_release,
};

int __init rtas_flash_init(void)
{
	int rc;

	if (!rtas_proc_dir) {
		printk(KERN_WARNING "rtas proc dir does not already exist");
		return -ENOENT;
	}

	firmware_flash_pde = create_flash_pde(FIRMWARE_FLASH_NAME,
					      &rtas_flash_operations);
	rc = initialize_flash_pde_data("ibm,update-flash-64-and-reboot",
				       sizeof(struct rtas_update_flash_t),
				       firmware_flash_pde);
	if (rc != 0)
		return rc;

	firmware_update_pde = create_flash_pde(FIRMWARE_UPDATE_NAME,
					       &rtas_flash_operations);
	rc = initialize_flash_pde_data("ibm,update-flash-64-and-reboot",
				       sizeof(struct rtas_update_flash_t),
				       firmware_update_pde);
	if (rc != 0)
		return rc;

	validate_pde = create_flash_pde(VALIDATE_FLASH_NAME,
					&validate_flash_operations);
	rc = initialize_flash_pde_data("ibm,validate-flash-image",
				       sizeof(struct rtas_validate_flash_t),
				       validate_pde);
	if (rc != 0)
		return rc;

	manage_pde = create_flash_pde(MANAGE_FLASH_NAME,
				      &manage_flash_operations);
	rc = initialize_flash_pde_data("ibm,manage-flash-image",
				       sizeof(struct rtas_manage_flash_t),
				       manage_pde);
	if (rc != 0)
		return rc;

	return 0;
}

void __exit rtas_flash_cleanup(void)
{
	if (!rtas_proc_dir)
		return;
	remove_flash_pde(firmware_flash_pde);
	remove_flash_pde(firmware_update_pde);
	remove_flash_pde(validate_pde);
	remove_flash_pde(manage_pde);
}

module_init(rtas_flash_init);
module_exit(rtas_flash_cleanup);
MODULE_LICENSE("GPL");