diff options
Diffstat (limited to 'drivers/scsi/scsi_netlink.c')
| -rw-r--r-- | drivers/scsi/scsi_netlink.c | 557 | 
1 files changed, 16 insertions, 541 deletions
diff --git a/drivers/scsi/scsi_netlink.c b/drivers/scsi/scsi_netlink.c index 8818dd681c1..65123a21b97 100644 --- a/drivers/scsi/scsi_netlink.c +++ b/drivers/scsi/scsi_netlink.c @@ -33,40 +33,6 @@  struct sock *scsi_nl_sock = NULL;  EXPORT_SYMBOL_GPL(scsi_nl_sock); -static DEFINE_SPINLOCK(scsi_nl_lock); -static struct list_head scsi_nl_drivers; - -static u32	scsi_nl_state; -#define STATE_EHANDLER_BSY		0x00000001 - -struct scsi_nl_transport { -	int (*msg_handler)(struct sk_buff *); -	void (*event_handler)(struct notifier_block *, unsigned long, void *); -	unsigned int refcnt; -	int flags; -}; - -/* flags values (bit flags) */ -#define HANDLER_DELETING		0x1 - -static struct scsi_nl_transport transports[SCSI_NL_MAX_TRANSPORTS] = -	{ {NULL, }, }; - - -struct scsi_nl_drvr { -	struct list_head next; -	int (*dmsg_handler)(struct Scsi_Host *shost, void *payload, -				 u32 len, u32 pid); -	void (*devt_handler)(struct notifier_block *nb, -				 unsigned long event, void *notify_ptr); -	struct scsi_host_template *hostt; -	u64 vendor_id; -	unsigned int refcnt; -	int flags; -}; - - -  /**   * scsi_nl_rcv_msg - Receive message handler.   * @skb:		socket receive buffer @@ -81,7 +47,6 @@ scsi_nl_rcv_msg(struct sk_buff *skb)  {  	struct nlmsghdr *nlh;  	struct scsi_nl_hdr *hdr; -	unsigned long flags;  	u32 rlen;  	int err, tport; @@ -126,22 +91,24 @@ scsi_nl_rcv_msg(struct sk_buff *skb)  		/*  		 * Deliver message to the appropriate transport  		 */ -		spin_lock_irqsave(&scsi_nl_lock, flags); -  		tport = hdr->transport; -		if ((tport < SCSI_NL_MAX_TRANSPORTS) && -		    !(transports[tport].flags & HANDLER_DELETING) && -		    (transports[tport].msg_handler)) { -			transports[tport].refcnt++; -			spin_unlock_irqrestore(&scsi_nl_lock, flags); -			err = transports[tport].msg_handler(skb); -			spin_lock_irqsave(&scsi_nl_lock, flags); -			transports[tport].refcnt--; -		} else +		if (tport == SCSI_NL_TRANSPORT) { +			switch (hdr->msgtype) { +			case SCSI_NL_SHOST_VENDOR: +				/* Locate the driver that corresponds to the message */ +				err = -ESRCH; +				break; +			default: +				err = -EBADR; +				break; +			} +			if (err) +				printk(KERN_WARNING "%s: Msgtype %d failed - err %d\n", +				       __func__, hdr->msgtype, err); +		} +		else  			err = -ENOENT; -		spin_unlock_irqrestore(&scsi_nl_lock, flags); -  next_msg:  		if ((err) || (nlh->nlmsg_flags & NLM_F_ACK))  			netlink_ack(skb, nlh, err); @@ -150,333 +117,6 @@ next_msg:  	}  } - -/** - * scsi_nl_rcv_event - Event handler for a netlink socket. - * @this:		event notifier block - * @event:		event type - * @ptr:		event payload - * - **/ -static int -scsi_nl_rcv_event(struct notifier_block *this, unsigned long event, void *ptr) -{ -	struct netlink_notify *n = ptr; -	struct scsi_nl_drvr *driver; -	unsigned long flags; -	int tport; - -	if (n->protocol != NETLINK_SCSITRANSPORT) -		return NOTIFY_DONE; - -	spin_lock_irqsave(&scsi_nl_lock, flags); -	scsi_nl_state |= STATE_EHANDLER_BSY; - -	/* -	 * Pass event on to any transports that may be listening -	 */ -	for (tport = 0; tport < SCSI_NL_MAX_TRANSPORTS; tport++) { -		if (!(transports[tport].flags & HANDLER_DELETING) && -		    (transports[tport].event_handler)) { -			spin_unlock_irqrestore(&scsi_nl_lock, flags); -			transports[tport].event_handler(this, event, ptr); -			spin_lock_irqsave(&scsi_nl_lock, flags); -		} -	} - -	/* -	 * Pass event on to any drivers that may be listening -	 */ -	list_for_each_entry(driver, &scsi_nl_drivers, next) { -		if (!(driver->flags & HANDLER_DELETING) && -		    (driver->devt_handler)) { -			spin_unlock_irqrestore(&scsi_nl_lock, flags); -			driver->devt_handler(this, event, ptr); -			spin_lock_irqsave(&scsi_nl_lock, flags); -		} -	} - -	scsi_nl_state &= ~STATE_EHANDLER_BSY; -	spin_unlock_irqrestore(&scsi_nl_lock, flags); - -	return NOTIFY_DONE; -} - -static struct notifier_block scsi_netlink_notifier = { -	.notifier_call  = scsi_nl_rcv_event, -}; - - -/* - * GENERIC SCSI transport receive and event handlers - */ - -/** - * scsi_generic_msg_handler - receive message handler for GENERIC transport messages - * @skb:		socket receive buffer - **/ -static int -scsi_generic_msg_handler(struct sk_buff *skb) -{ -	struct nlmsghdr *nlh = nlmsg_hdr(skb); -	struct scsi_nl_hdr *snlh = NLMSG_DATA(nlh); -	struct scsi_nl_drvr *driver; -	struct Scsi_Host *shost; -	unsigned long flags; -	int err = 0, match, pid; - -	pid = NETLINK_CREDS(skb)->pid; - -	switch (snlh->msgtype) { -	case SCSI_NL_SHOST_VENDOR: -		{ -		struct scsi_nl_host_vendor_msg *msg = NLMSG_DATA(nlh); - -		/* Locate the driver that corresponds to the message */ -		spin_lock_irqsave(&scsi_nl_lock, flags); -		match = 0; -		list_for_each_entry(driver, &scsi_nl_drivers, next) { -			if (driver->vendor_id == msg->vendor_id) { -				match = 1; -				break; -			} -		} - -		if ((!match) || (!driver->dmsg_handler)) { -			spin_unlock_irqrestore(&scsi_nl_lock, flags); -			err = -ESRCH; -			goto rcv_exit; -		} - -		if (driver->flags & HANDLER_DELETING) { -			spin_unlock_irqrestore(&scsi_nl_lock, flags); -			err = -ESHUTDOWN; -			goto rcv_exit; -		} - -		driver->refcnt++; -		spin_unlock_irqrestore(&scsi_nl_lock, flags); - - -		/* if successful, scsi_host_lookup takes a shost reference */ -		shost = scsi_host_lookup(msg->host_no); -		if (!shost) { -			err = -ENODEV; -			goto driver_exit; -		} - -		/* is this host owned by the vendor ? */ -		if (shost->hostt != driver->hostt) { -			err = -EINVAL; -			goto vendormsg_put; -		} - -		/* pass message on to the driver */ -		err = driver->dmsg_handler(shost, (void *)&msg[1], -					 msg->vmsg_datalen, pid); - -vendormsg_put: -		/* release reference by scsi_host_lookup */ -		scsi_host_put(shost); - -driver_exit: -		/* release our own reference on the registration object */ -		spin_lock_irqsave(&scsi_nl_lock, flags); -		driver->refcnt--; -		spin_unlock_irqrestore(&scsi_nl_lock, flags); -		break; -		} - -	default: -		err = -EBADR; -		break; -	} - -rcv_exit: -	if (err) -		printk(KERN_WARNING "%s: Msgtype %d failed - err %d\n", -			 __func__, snlh->msgtype, err); -	return err; -} - - -/** - * scsi_nl_add_transport - - *    Registers message and event handlers for a transport. Enables - *    receipt of netlink messages and events to a transport. - * - * @tport:		transport registering handlers - * @msg_handler:	receive message handler callback - * @event_handler:	receive event handler callback - **/ -int -scsi_nl_add_transport(u8 tport, -	int (*msg_handler)(struct sk_buff *), -	void (*event_handler)(struct notifier_block *, unsigned long, void *)) -{ -	unsigned long flags; -	int err = 0; - -	if (tport >= SCSI_NL_MAX_TRANSPORTS) -		return -EINVAL; - -	spin_lock_irqsave(&scsi_nl_lock, flags); - -	if (scsi_nl_state & STATE_EHANDLER_BSY) { -		spin_unlock_irqrestore(&scsi_nl_lock, flags); -		msleep(1); -		spin_lock_irqsave(&scsi_nl_lock, flags); -	} - -	if (transports[tport].msg_handler || transports[tport].event_handler) { -		err = -EALREADY; -		goto register_out; -	} - -	transports[tport].msg_handler = msg_handler; -	transports[tport].event_handler = event_handler; -	transports[tport].flags = 0; -	transports[tport].refcnt = 0; - -register_out: -	spin_unlock_irqrestore(&scsi_nl_lock, flags); - -	return err; -} -EXPORT_SYMBOL_GPL(scsi_nl_add_transport); - - -/** - * scsi_nl_remove_transport - - *    Disable transport receiption of messages and events - * - * @tport:		transport deregistering handlers - * - **/ -void -scsi_nl_remove_transport(u8 tport) -{ -	unsigned long flags; - -	spin_lock_irqsave(&scsi_nl_lock, flags); -	if (scsi_nl_state & STATE_EHANDLER_BSY) { -		spin_unlock_irqrestore(&scsi_nl_lock, flags); -		msleep(1); -		spin_lock_irqsave(&scsi_nl_lock, flags); -	} - -	if (tport < SCSI_NL_MAX_TRANSPORTS) { -		transports[tport].flags |= HANDLER_DELETING; - -		while (transports[tport].refcnt != 0) { -			spin_unlock_irqrestore(&scsi_nl_lock, flags); -			schedule_timeout_uninterruptible(HZ/4); -			spin_lock_irqsave(&scsi_nl_lock, flags); -		} -		transports[tport].msg_handler = NULL; -		transports[tport].event_handler = NULL; -		transports[tport].flags = 0; -	} - -	spin_unlock_irqrestore(&scsi_nl_lock, flags); - -	return; -} -EXPORT_SYMBOL_GPL(scsi_nl_remove_transport); - - -/** - * scsi_nl_add_driver - - *    A driver is registering its interfaces for SCSI netlink messages - * - * @vendor_id:          A unique identification value for the driver. - * @hostt:		address of the driver's host template. Used - *			to verify an shost is bound to the driver - * @nlmsg_handler:	receive message handler callback - * @nlevt_handler:	receive event handler callback - * - * Returns: - *   0 on Success - *   error result otherwise - **/ -int -scsi_nl_add_driver(u64 vendor_id, struct scsi_host_template *hostt, -	int (*nlmsg_handler)(struct Scsi_Host *shost, void *payload, -				 u32 len, u32 pid), -	void (*nlevt_handler)(struct notifier_block *nb, -				 unsigned long event, void *notify_ptr)) -{ -	struct scsi_nl_drvr *driver; -	unsigned long flags; - -	driver = kzalloc(sizeof(*driver), GFP_KERNEL); -	if (unlikely(!driver)) { -		printk(KERN_ERR "%s: allocation failure\n", __func__); -		return -ENOMEM; -	} - -	driver->dmsg_handler = nlmsg_handler; -	driver->devt_handler = nlevt_handler; -	driver->hostt = hostt; -	driver->vendor_id = vendor_id; - -	spin_lock_irqsave(&scsi_nl_lock, flags); -	if (scsi_nl_state & STATE_EHANDLER_BSY) { -		spin_unlock_irqrestore(&scsi_nl_lock, flags); -		msleep(1); -		spin_lock_irqsave(&scsi_nl_lock, flags); -	} -	list_add_tail(&driver->next, &scsi_nl_drivers); -	spin_unlock_irqrestore(&scsi_nl_lock, flags); - -	return 0; -} -EXPORT_SYMBOL_GPL(scsi_nl_add_driver); - - -/** - * scsi_nl_remove_driver - - *    An driver is unregistering with the SCSI netlink messages - * - * @vendor_id:          The unique identification value for the driver. - **/ -void -scsi_nl_remove_driver(u64 vendor_id) -{ -	struct scsi_nl_drvr *driver; -	unsigned long flags; - -	spin_lock_irqsave(&scsi_nl_lock, flags); -	if (scsi_nl_state & STATE_EHANDLER_BSY) { -		spin_unlock_irqrestore(&scsi_nl_lock, flags); -		msleep(1); -		spin_lock_irqsave(&scsi_nl_lock, flags); -	} - -	list_for_each_entry(driver, &scsi_nl_drivers, next) { -		if (driver->vendor_id == vendor_id) { -			driver->flags |= HANDLER_DELETING; -			while (driver->refcnt != 0) { -				spin_unlock_irqrestore(&scsi_nl_lock, flags); -				schedule_timeout_uninterruptible(HZ/4); -				spin_lock_irqsave(&scsi_nl_lock, flags); -			} -			list_del(&driver->next); -			kfree(driver); -			spin_unlock_irqrestore(&scsi_nl_lock, flags); -			return; -		} -	} - -	spin_unlock_irqrestore(&scsi_nl_lock, flags); - -	printk(KERN_ERR "%s: removal of driver failed - vendor_id 0x%llx\n", -	       __func__, (unsigned long long)vendor_id); -	return; -} -EXPORT_SYMBOL_GPL(scsi_nl_remove_driver); - -  /**   * scsi_netlink_init - Called by SCSI subsystem to initialize   * 	the SCSI transport netlink interface @@ -485,36 +125,19 @@ EXPORT_SYMBOL_GPL(scsi_nl_remove_driver);  void  scsi_netlink_init(void)  { -	int error;  	struct netlink_kernel_cfg cfg = {  		.input	= scsi_nl_rcv_msg,  		.groups	= SCSI_NL_GRP_CNT,  	}; -	INIT_LIST_HEAD(&scsi_nl_drivers); - -	error = netlink_register_notifier(&scsi_netlink_notifier); -	if (error) { -		printk(KERN_ERR "%s: register of event handler failed - %d\n", -				__func__, error); -		return; -	} -  	scsi_nl_sock = netlink_kernel_create(&init_net, NETLINK_SCSITRANSPORT, -					     THIS_MODULE, &cfg); +					     &cfg);  	if (!scsi_nl_sock) {  		printk(KERN_ERR "%s: register of receive handler failed\n",  				__func__); -		netlink_unregister_notifier(&scsi_netlink_notifier);  		return;  	} -	/* Register the entry points for the generic SCSI transport */ -	error = scsi_nl_add_transport(SCSI_NL_TRANSPORT, -				scsi_generic_msg_handler, NULL); -	if (error) -		printk(KERN_ERR "%s: register of GENERIC transport handler" -				"  failed - %d\n", __func__, error);  	return;  } @@ -526,158 +149,10 @@ scsi_netlink_init(void)  void  scsi_netlink_exit(void)  { -	scsi_nl_remove_transport(SCSI_NL_TRANSPORT); -  	if (scsi_nl_sock) {  		netlink_kernel_release(scsi_nl_sock); -		netlink_unregister_notifier(&scsi_netlink_notifier);  	}  	return;  } - -/* - * Exported Interfaces - */ - -/** - * scsi_nl_send_transport_msg - - *    Generic function to send a single message from a SCSI transport to - *    a single process - * - * @pid:		receiving pid - * @hdr:		message payload - * - **/ -void -scsi_nl_send_transport_msg(u32 pid, struct scsi_nl_hdr *hdr) -{ -	struct sk_buff *skb; -	struct nlmsghdr	*nlh; -	const char *fn; -	char *datab; -	u32 len, skblen; -	int err; - -	if (!scsi_nl_sock) { -		err = -ENOENT; -		fn = "netlink socket"; -		goto msg_fail; -	} - -	len = NLMSG_SPACE(hdr->msglen); -	skblen = NLMSG_SPACE(len); - -	skb = alloc_skb(skblen, GFP_KERNEL); -	if (!skb) { -		err = -ENOBUFS; -		fn = "alloc_skb"; -		goto msg_fail; -	} - -	nlh = nlmsg_put(skb, pid, 0, SCSI_TRANSPORT_MSG, len - sizeof(*nlh), 0); -	if (!nlh) { -		err = -ENOBUFS; -		fn = "nlmsg_put"; -		goto msg_fail_skb; -	} -	datab = NLMSG_DATA(nlh); -	memcpy(datab, hdr, hdr->msglen); - -	err = nlmsg_unicast(scsi_nl_sock, skb, pid); -	if (err < 0) { -		fn = "nlmsg_unicast"; -		/* nlmsg_unicast already kfree_skb'd */ -		goto msg_fail; -	} - -	return; - -msg_fail_skb: -	kfree_skb(skb); -msg_fail: -	printk(KERN_WARNING -		"%s: Dropped Message : pid %d Transport %d, msgtype x%x, " -		"msglen %d: %s : err %d\n", -		__func__, pid, hdr->transport, hdr->msgtype, hdr->msglen, -		fn, err); -	return; -} -EXPORT_SYMBOL_GPL(scsi_nl_send_transport_msg); - - -/** - * scsi_nl_send_vendor_msg - called to send a shost vendor unique message - *                      to a specific process id. - * - * @pid:		process id of the receiver - * @host_no:		host # sending the message - * @vendor_id:		unique identifier for the driver's vendor - * @data_len:		amount, in bytes, of vendor unique payload data - * @data_buf:		pointer to vendor unique data buffer - * - * Returns: - *   0 on successful return - *   otherwise, failing error code - * - * Notes: - *	This routine assumes no locks are held on entry. - */ -int -scsi_nl_send_vendor_msg(u32 pid, unsigned short host_no, u64 vendor_id, -			 char *data_buf, u32 data_len) -{ -	struct sk_buff *skb; -	struct nlmsghdr	*nlh; -	struct scsi_nl_host_vendor_msg *msg; -	u32 len, skblen; -	int err; - -	if (!scsi_nl_sock) { -		err = -ENOENT; -		goto send_vendor_fail; -	} - -	len = SCSI_NL_MSGALIGN(sizeof(*msg) + data_len); -	skblen = NLMSG_SPACE(len); - -	skb = alloc_skb(skblen, GFP_KERNEL); -	if (!skb) { -		err = -ENOBUFS; -		goto send_vendor_fail; -	} - -	nlh = nlmsg_put(skb, 0, 0, SCSI_TRANSPORT_MSG, -				skblen - sizeof(*nlh), 0); -	if (!nlh) { -		err = -ENOBUFS; -		goto send_vendor_fail_skb; -	} -	msg = NLMSG_DATA(nlh); - -	INIT_SCSI_NL_HDR(&msg->snlh, SCSI_NL_TRANSPORT, -				SCSI_NL_SHOST_VENDOR, len); -	msg->vendor_id = vendor_id; -	msg->host_no = host_no; -	msg->vmsg_datalen = data_len;	/* bytes */ -	memcpy(&msg[1], data_buf, data_len); - -	err = nlmsg_unicast(scsi_nl_sock, skb, pid); -	if (err) -		/* nlmsg_multicast already kfree_skb'd */ -		goto send_vendor_fail; - -	return 0; - -send_vendor_fail_skb: -	kfree_skb(skb); -send_vendor_fail: -	printk(KERN_WARNING -		"%s: Dropped SCSI Msg : host %d vendor_unique - err %d\n", -		__func__, host_no, err); -	return err; -} -EXPORT_SYMBOL(scsi_nl_send_vendor_msg); - -  |