Commit 912a8460 authored by NeilBrown's avatar NeilBrown Committed by Greg Kroah-Hartman
Browse files

staging: lustre: replace libcfs_register_ioctl with a blocking notifier_chain 



libcfs allows other modules to register handlers for ioctls.
The implementation it uses for this is nearly identical to a
blocking notifier chain, so change to use that.

The biggest difference is that the return value from notifier has a
defined format, where libcfs_register_ioctl uses -EINVAL to mean
"continue".  This requires a little bit of conversion.

Signed-off-by: default avatarNeilBrown <neilb@suse.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 6afe572b

drivers/staging/lustre/include/linux/libcfs/libcfs.h

+7 −12
Original line number Diff line number Diff line
@@ -93,19 +93,14 @@ 
#define LNET_ACCEPTOR_MIN_RESERVED_PORT    512

#define LNET_ACCEPTOR_MAX_RESERVED_PORT    1023



struct libcfs_ioctl_handler {

	struct list_head item;

	int (*handle_ioctl)(unsigned int cmd, struct libcfs_ioctl_hdr *hdr);

};



#define DECLARE_IOCTL_HANDLER(ident, func)			\

	struct libcfs_ioctl_handler ident = {			\

		.item		= LIST_HEAD_INIT(ident.item),	\

		.handle_ioctl	= func				\

extern struct blocking_notifier_head libcfs_ioctl_list;

static inline int notifier_from_ioctl_errno(int err)

{

	if (err == -EINVAL)

		return NOTIFY_OK;

	return notifier_from_errno(err) | NOTIFY_STOP_MASK;

}



int libcfs_register_ioctl(struct libcfs_ioctl_handler *hand);

int libcfs_deregister_ioctl(struct libcfs_ioctl_handler *hand);

int libcfs_setup(void);



#define _LIBCFS_H

drivers/staging/lustre/lnet/libcfs/module.c

+14 −50
Original line number Diff line number Diff line
@@ -62,38 +62,8 @@ 


static struct dentry *lnet_debugfs_root;



static DECLARE_RWSEM(ioctl_list_sem);

static LIST_HEAD(ioctl_list);



int libcfs_register_ioctl(struct libcfs_ioctl_handler *hand)

{

	int rc = 0;



	down_write(&ioctl_list_sem);

	if (!list_empty(&hand->item))

		rc = -EBUSY;

	else

		list_add_tail(&hand->item, &ioctl_list);

	up_write(&ioctl_list_sem);



	return rc;

}

EXPORT_SYMBOL(libcfs_register_ioctl);



int libcfs_deregister_ioctl(struct libcfs_ioctl_handler *hand)

{

	int rc = 0;



	down_write(&ioctl_list_sem);

	if (list_empty(&hand->item))

		rc = -ENOENT;

	else

		list_del_init(&hand->item);

	up_write(&ioctl_list_sem);



	return rc;

}

EXPORT_SYMBOL(libcfs_deregister_ioctl);

BLOCKING_NOTIFIER_HEAD(libcfs_ioctl_list);

EXPORT_SYMBOL(libcfs_ioctl_list);



static inline size_t libcfs_ioctl_packlen(struct libcfs_ioctl_data *data)

{
@@ -268,25 +238,19 @@ static int libcfs_ioctl(unsigned long cmd, void __user *uparam) 
		libcfs_debug_mark_buffer(data->ioc_inlbuf1);

		break;



	default: {

		struct libcfs_ioctl_handler *hand;



	default:

		err = blocking_notifier_call_chain(&libcfs_ioctl_list,

						   cmd, hdr);

		if (!(err & NOTIFY_STOP_MASK))

			/* No-one claimed the ioctl */

			err = -EINVAL;

		down_read(&ioctl_list_sem);

		list_for_each_entry(hand, &ioctl_list, item) {

			err = hand->handle_ioctl(cmd, hdr);

			if (err == -EINVAL)

				continue;



			if (!err) {

		else

			err = notifier_to_errno(err);

		if (!err)

			if (copy_to_user(uparam, hdr, hdr->ioc_len))

				err = -EFAULT;

			}

		break;

	}

		up_read(&ioctl_list_sem);

		break; }

	}

out:

	kvfree(hdr);

	return err;

drivers/staging/lustre/lnet/lnet/module.c

+25 −13
Original line number Diff line number Diff line
@@ -136,30 +136,37 @@ lnet_dyn_unconfigure(struct libcfs_ioctl_hdr *hdr) 
}



static int

lnet_ioctl(unsigned int cmd, struct libcfs_ioctl_hdr *hdr)

lnet_ioctl(struct notifier_block *nb,

	   unsigned long cmd, void *vdata)

{

	int rc;

	struct libcfs_ioctl_hdr *hdr = vdata;



	switch (cmd) {

	case IOC_LIBCFS_CONFIGURE: {

		struct libcfs_ioctl_data *data =

			(struct libcfs_ioctl_data *)hdr;



		if (data->ioc_hdr.ioc_len < sizeof(*data))

			return -EINVAL;



		if (data->ioc_hdr.ioc_len < sizeof(*data)) {

			rc = -EINVAL;

		} else {

			the_lnet.ln_nis_from_mod_params = data->ioc_flags;

		return lnet_configure(NULL);

			rc = lnet_configure(NULL);

		}

		break;

	}



	case IOC_LIBCFS_UNCONFIGURE:

		return lnet_unconfigure();

		rc = lnet_unconfigure();

		break;



	case IOC_LIBCFS_ADD_NET:

		return lnet_dyn_configure(hdr);

		rc = lnet_dyn_configure(hdr);

		break;



	case IOC_LIBCFS_DEL_NET:

		return lnet_dyn_unconfigure(hdr);

		rc = lnet_dyn_unconfigure(hdr);

		break;



	default:

		/*
@@ -172,11 +179,14 @@ lnet_ioctl(unsigned int cmd, struct libcfs_ioctl_hdr *hdr) 
			rc = LNetCtl(cmd, hdr);

			LNetNIFini();

		}

		return rc;

		break;

	}

	return notifier_from_ioctl_errno(rc);

}



static DECLARE_IOCTL_HANDLER(lnet_ioctl_handler, lnet_ioctl);

static struct notifier_block lnet_ioctl_handler = {

	.notifier_call = lnet_ioctl,

};



static int __init lnet_init(void)

{
@@ -194,7 +204,8 @@ static int __init lnet_init(void) 
		return rc;

	}



	rc = libcfs_register_ioctl(&lnet_ioctl_handler);

	rc = blocking_notifier_chain_register(&libcfs_ioctl_list,

					      &lnet_ioctl_handler);

	LASSERT(!rc);



	if (config_on_load) {
@@ -212,7 +223,8 @@ static void __exit lnet_exit(void) 
{

	int rc;



	rc = libcfs_deregister_ioctl(&lnet_ioctl_handler);

	rc = blocking_notifier_chain_unregister(&libcfs_ioctl_list,

						&lnet_ioctl_handler);

	LASSERT(!rc);



	lnet_lib_exit();

drivers/staging/lustre/lnet/selftest/conctl.c

+15 −12
Original line number Diff line number Diff line
@@ -680,32 +680,34 @@ static int lst_test_add_ioctl(struct lstio_test_args *args) 
}



int

lstcon_ioctl_entry(unsigned int cmd, struct libcfs_ioctl_hdr *hdr)

lstcon_ioctl_entry(struct notifier_block *nb,

		   unsigned long cmd, void *vdata)

{

	char *buf;

	struct libcfs_ioctl_hdr *hdr = vdata;

	char *buf = NULL;

	struct libcfs_ioctl_data *data;

	int opc;

	int rc;

	int rc = -EINVAL;



	if (cmd != IOC_LIBCFS_LNETST)

		return -EINVAL;

		goto err;



	data = container_of(hdr, struct libcfs_ioctl_data, ioc_hdr);



	opc = data->ioc_u32[0];



	if (data->ioc_plen1 > PAGE_SIZE)

		return -EINVAL;

		goto err;



	buf = kmalloc(data->ioc_plen1, GFP_KERNEL);

	rc = -ENOMEM;

	if (!buf)

		return -ENOMEM;

		goto err;



	/* copy in parameter */

	if (copy_from_user(buf, data->ioc_pbuf1, data->ioc_plen1)) {

		kfree(buf);

		return -EFAULT;

	}

	rc = -EFAULT;

	if (copy_from_user(buf, data->ioc_pbuf1, data->ioc_plen1))

		goto err;



	mutex_lock(&console_session.ses_mutex);
@@ -785,6 +787,7 @@ lstcon_ioctl_entry(unsigned int cmd, struct libcfs_ioctl_hdr *hdr) 
		break;

	default:

		rc = -EINVAL;

		goto out;

	}



	if (copy_to_user(data->ioc_pbuf2, &console_session.ses_trans_stat,
@@ -792,8 +795,8 @@ lstcon_ioctl_entry(unsigned int cmd, struct libcfs_ioctl_hdr *hdr) 
		rc = -EFAULT;

out:

	mutex_unlock(&console_session.ses_mutex);



err:

	kfree(buf);



	return rc;

	return notifier_from_ioctl_errno(rc);

}

drivers/staging/lustre/lnet/selftest/console.c

+7 −3
Original line number Diff line number Diff line
@@ -1996,7 +1996,9 @@ static void lstcon_init_acceptor_service(void) 
	lstcon_acceptor_service.sv_wi_total = SFW_FRWK_WI_MAX;

}



static DECLARE_IOCTL_HANDLER(lstcon_ioctl_handler, lstcon_ioctl_entry);

static struct notifier_block lstcon_ioctl_handler = {

	.notifier_call = lstcon_ioctl_entry,

};



/* initialize console */

int
@@ -2048,7 +2050,8 @@ lstcon_console_init(void) 
		goto out;

	}



	rc = libcfs_register_ioctl(&lstcon_ioctl_handler);

	rc = blocking_notifier_chain_register(&libcfs_ioctl_list,

					      &lstcon_ioctl_handler);



	if (!rc) {

		lstcon_rpc_module_init();
@@ -2071,7 +2074,8 @@ lstcon_console_fini(void) 
{

	int i;



	libcfs_deregister_ioctl(&lstcon_ioctl_handler);

	blocking_notifier_chain_unregister(&libcfs_ioctl_list,

					   &lstcon_ioctl_handler);



	mutex_lock(&console_session.ses_mutex);