Commit 26e91b75 authored by Thomas Gleixner's avatar Thomas Gleixner
Browse files

genirq/msi: Provide msi_match_device_domain() 



Provide an interface to match a per device domain bus token. This allows to
query which type of domain is installed for a particular domain id. Will be
used for PCI to avoid frequent create/remove cycles for the MSI resp. MSI-X
domains.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Reviewed-by: default avatarKevin Tian <kevin.tian@intel.com>
Acked-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221124232325.738047902@linutronix.de
parent 27a6dea3

include/linux/msi.h

+3 −0
Original line number Diff line number Diff line
@@ -553,6 +553,9 @@ bool msi_create_device_irq_domain(struct device *dev, unsigned int domid, 
				  void *chip_data);

void msi_remove_device_irq_domain(struct device *dev, unsigned int domid);



bool msi_match_device_irq_domain(struct device *dev, unsigned int domid,

				 enum irq_domain_bus_token bus_token);



int msi_domain_alloc_irqs_range_locked(struct device *dev, unsigned int domid,

				       unsigned int first, unsigned int last);

int msi_domain_alloc_irqs_range(struct device *dev, unsigned int domid,

kernel/irq/msi.c

+25 −0
Original line number Diff line number Diff line
@@ -986,6 +986,31 @@ void msi_remove_device_irq_domain(struct device *dev, unsigned int domid) 
	msi_unlock_descs(dev);

}



/**

 * msi_match_device_irq_domain - Match a device irq domain against a bus token

 * @dev:	Pointer to the device

 * @domid:	Domain id

 * @bus_token:	Bus token to match against the domain bus token

 *

 * Return: True if device domain exists and bus tokens match.

 */

bool msi_match_device_irq_domain(struct device *dev, unsigned int domid,

				 enum irq_domain_bus_token bus_token)

{

	struct msi_domain_info *info;

	struct irq_domain *domain;

	bool ret = false;



	msi_lock_descs(dev);

	domain = msi_get_device_domain(dev, domid);

	if (domain && irq_domain_is_msi_device(domain)) {

		info = domain->host_data;

		ret = info->bus_token == bus_token;

	}

	msi_unlock_descs(dev);

	return ret;

}



int msi_domain_prepare_irqs(struct irq_domain *domain, struct device *dev,

			    int nvec, msi_alloc_info_t *arg)

{