rtas_flash.c

linux 内核源代码

				size_t count, loff_t *off)
{
	struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
	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");
	int update_results;
	s32 rc;	

	rc = 0;
	do {
		spin_lock(&rtas_data_buf_lock);
		memcpy(rtas_data_buf, args_buf->buf, VALIDATE_BUF_SIZE);
		rc = rtas_call(token, 2, 2, &update_results, 
			       (u32) __pa(rtas_data_buf), args_buf->buf_size);
		memcpy(args_buf->buf, rtas_data_buf, VALIDATE_BUF_SIZE);
		spin_unlock(&rtas_data_buf_lock);
	} while (rtas_busy_delay(rc));

	args_buf->status = rc;
	args_buf->update_results = 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 __user *buf,
			       size_t count, loff_t *ppos)
{
	struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
	struct rtas_validate_flash_t *args_buf;
	char msg[RTAS_MSG_MAXLEN];
	int msglen;

	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;

	if (!access_ok(VERIFY_WRITE, buf, msglen))
		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 __user *buf,
				    size_t count, loff_t *off)
{
	struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
	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 (!access_ok(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 = PDE(file->f_path.dentry->d_inode);
	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);
	}

	/* The matching atomic_inc was in rtas_excl_open() */
	atomic_dec(&dp->count);

	return 0;
}

static void rtas_flash_firmware(int reboot_type)
{
	unsigned long image_size;
	struct flash_block_list *f, *next, *flist;
	unsigned long rtas_block_list;
	int i, status, update_token;

	if (rtas_firmware_flash_list.next == NULL)
		return;		/* nothing to do */

	if (reboot_type != SYS_RESTART) {
		printk(KERN_ALERT "FLASH: firmware flash requires a reboot\n");
		printk(KERN_ALERT "FLASH: the firmware image will NOT be flashed\n");
		return;
	}

	update_token = rtas_token("ibm,update-flash-64-and-reboot");
	if (update_token == RTAS_UNKNOWN_SERVICE) {
		printk(KERN_ALERT "FLASH: ibm,update-flash-64-and-reboot "
		       "is not available -- not a service partition?\n");
		printk(KERN_ALERT "FLASH: firmware will not be flashed\n");
		return;
	}

	/* NOTE: the "first" block list is a global var with no data
	 * blocks in the kernel data segment.  We do this because
	 * we want to ensure this block_list addr is under 4GB.
	 */
	rtas_firmware_flash_list.num_blocks = 0;
	flist = (struct flash_block_list *)&rtas_firmware_flash_list;
	rtas_block_list = virt_to_abs(flist);
	if (rtas_block_list >= 4UL*1024*1024*1024) {
		printk(KERN_ALERT "FLASH: kernel bug...flash list header addr above 4GB\n");
		return;
	}

	printk(KERN_ALERT "FLASH: preparing saved firmware image for flash\n");
	/* Update the block_list in place. */
	image_size = 0;
	for (f = flist; f; f = next) {
		/* Translate data addrs to absolute */
		for (i = 0; i < f->num_blocks; i++) {
			f->blocks[i].data = (char *)virt_to_abs(f->blocks[i].data);
			image_size += f->blocks[i].length;
		}
		next = f->next;
		/* Don't translate NULL pointer for last entry */
		if (f->next)
			f->next = (struct flash_block_list *)virt_to_abs(f->next);
		else
			f->next = NULL;
		/* make num_blocks into the version/length field */
		f->num_blocks = (FLASH_BLOCK_LIST_VERSION << 56) | ((f->num_blocks+1)*16);
	}

	printk(KERN_ALERT "FLASH: flash image is %ld bytes\n", image_size);
	printk(KERN_ALERT "FLASH: performing flash and reboot\n");
	rtas_progress("Flashing        \n", 0x0);
	rtas_progress("Please Wait...  ", 0x0);
	printk(KERN_ALERT "FLASH: this will take several minutes.  Do not power off!\n");
	status = rtas_call(update_token, 1, 1, NULL, rtas_block_list);
	switch (status) {	/* should only get "bad" status */
	    case 0:
		printk(KERN_ALERT "FLASH: success\n");
		break;
	    case -1:
		printk(KERN_ALERT "FLASH: hardware error.  Firmware may not be not flashed\n");
		break;
	    case -3:
		printk(KERN_ALERT "FLASH: image is corrupt or not correct for this platform.  Firmware not flashed\n");
		break;
	    case -4:
		printk(KERN_ALERT "FLASH: flash failed when partially complete.  System may not reboot\n");
		break;
	    default:
		printk(KERN_ALERT "FLASH: unknown flash return code %d\n", status);
		break;
	}
}

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

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

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

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

	return ent;
}

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

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

static const 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_token("ibm,update-flash-64-and-reboot") ==
		       RTAS_UNKNOWN_SERVICE) {
		printk(KERN_ERR "rtas_flash: no firmware flash support\n");
		return 1;
	}

	firmware_flash_pde = create_flash_pde("ppc64/rtas/"
					      FIRMWARE_FLASH_NAME,
					      &rtas_flash_operations);
	if (firmware_flash_pde == NULL) {
		rc = -ENOMEM;
		goto cleanup;
	}

	rc = initialize_flash_pde_data("ibm,update-flash-64-and-reboot",
			 	       sizeof(struct rtas_update_flash_t), 
				       firmware_flash_pde);
	if (rc != 0)
		goto cleanup;

	firmware_update_pde = create_flash_pde("ppc64/rtas/"
					       FIRMWARE_UPDATE_NAME,
					       &rtas_flash_operations);
	if (firmware_update_pde == NULL) {
		rc = -ENOMEM;
		goto cleanup;
	}

	rc = initialize_flash_pde_data("ibm,update-flash-64-and-reboot",
			 	       sizeof(struct rtas_update_flash_t), 
				       firmware_update_pde);
	if (rc != 0)
		goto cleanup;

	validate_pde = create_flash_pde("ppc64/rtas/" VALIDATE_FLASH_NAME,
			      		&validate_flash_operations);
	if (validate_pde == NULL) {
		rc = -ENOMEM;
		goto cleanup;
	}

	rc = initialize_flash_pde_data("ibm,validate-flash-image",
		                       sizeof(struct rtas_validate_flash_t), 
				       validate_pde);
	if (rc != 0)
		goto cleanup;

	manage_pde = create_flash_pde("ppc64/rtas/" MANAGE_FLASH_NAME,
				      &manage_flash_operations);
	if (manage_pde == NULL) {
		rc = -ENOMEM;
		goto cleanup;
	}

	rc = initialize_flash_pde_data("ibm,manage-flash-image",
			               sizeof(struct rtas_manage_flash_t),
				       manage_pde);
	if (rc != 0)
		goto cleanup;

	rtas_flash_term_hook = rtas_flash_firmware;

	flash_block_cache = kmem_cache_create("rtas_flash_cache",
				RTAS_BLK_SIZE, RTAS_BLK_SIZE, 0,
				rtas_block_ctor);
	if (!flash_block_cache) {
		printk(KERN_ERR "%s: failed to create block cache\n",
				__FUNCTION__);
		rc = -ENOMEM;
		goto cleanup;
	}
	return 0;

cleanup:
	remove_flash_pde(firmware_flash_pde);
	remove_flash_pde(firmware_update_pde);
	remove_flash_pde(validate_pde);
	remove_flash_pde(manage_pde);

	return rc;
}

void __exit rtas_flash_cleanup(void)
{
	rtas_flash_term_hook = NULL;

	if (flash_block_cache)
		kmem_cache_destroy(flash_block_cache);

	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");