Commit 1cf362e9 authored by Kishon Vijay Abraham I's avatar Kishon Vijay Abraham I Committed by Lorenzo Pieralisi
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PCI: endpoint: Add support to add virtual function in endpoint core 



Add support to add virtual function in endpoint core. The virtual
function can only be associated with a physical function instead of a
endpoint controller. Provide APIs to associate a virtual function with
a physical function here.

[weiyongjun1@huawei.com: PCI: endpoint: Fix missing unlock on error in
 pci_epf_add_vepf() - Reported-by: default avatarHulk Robot <hulkci@huawei.com&gt;]>

Link: https://lore.kernel.org/r/20210819123343.1951-3-kishon@ti.com


Signed-off-by: default avatarKishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: default avatarWei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: default avatarLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
parent f00bfc64

drivers/pci/endpoint/pci-epc-core.c

+1 −1
Original line number Diff line number Diff line
@@ -548,7 +548,7 @@ int pci_epc_add_epf(struct pci_epc *epc, struct pci_epf *epf, 
	u32 func_no;

	int ret = 0;



	if (IS_ERR_OR_NULL(epc))

	if (IS_ERR_OR_NULL(epc) || epf->is_vf)

		return -EINVAL;



	if (type == PRIMARY_INTERFACE && epf->epc)

drivers/pci/endpoint/pci-epf-core.c

+97 −1
Original line number Diff line number Diff line
@@ -62,12 +62,19 @@ EXPORT_SYMBOL_GPL(pci_epf_type_add_cfs); 
 */

void pci_epf_unbind(struct pci_epf *epf)

{

	struct pci_epf *epf_vf;



	if (!epf->driver) {

		dev_WARN(&epf->dev, "epf device not bound to driver\n");

		return;

	}



	mutex_lock(&epf->lock);

	list_for_each_entry(epf_vf, &epf->pci_vepf, list) {

		if (epf_vf->is_bound)

			epf_vf->driver->ops->unbind(epf_vf);

	}

	if (epf->is_bound)

		epf->driver->ops->unbind(epf);

	mutex_unlock(&epf->lock);

	module_put(epf->driver->owner);
@@ -83,6 +90,7 @@ EXPORT_SYMBOL_GPL(pci_epf_unbind); 
 */

int pci_epf_bind(struct pci_epf *epf)

{

	struct pci_epf *epf_vf;

	int ret;



	if (!epf->driver) {
@@ -94,13 +102,97 @@ int pci_epf_bind(struct pci_epf *epf) 
		return -EAGAIN;



	mutex_lock(&epf->lock);

	list_for_each_entry(epf_vf, &epf->pci_vepf, list) {

		epf_vf->func_no = epf->func_no;

		epf_vf->epc = epf->epc;

		epf_vf->sec_epc = epf->sec_epc;

		ret = epf_vf->driver->ops->bind(epf_vf);

		if (ret)

			goto ret;

		epf_vf->is_bound = true;

	}



	ret = epf->driver->ops->bind(epf);

	if (ret)

		goto ret;

	epf->is_bound = true;



	mutex_unlock(&epf->lock);

	return 0;



ret:

	mutex_unlock(&epf->lock);

	pci_epf_unbind(epf);



	return ret;

}

EXPORT_SYMBOL_GPL(pci_epf_bind);



/**

 * pci_epf_add_vepf() - associate virtual EP function to physical EP function

 * @epf_pf: the physical EP function to which the virtual EP function should be

 *   associated

 * @epf_vf: the virtual EP function to be added

 *

 * A physical endpoint function can be associated with multiple virtual

 * endpoint functions. Invoke pci_epf_add_epf() to add a virtual PCI endpoint

 * function to a physical PCI endpoint function.

 */

int pci_epf_add_vepf(struct pci_epf *epf_pf, struct pci_epf *epf_vf)

{

	u32 vfunc_no;



	if (IS_ERR_OR_NULL(epf_pf) || IS_ERR_OR_NULL(epf_vf))

		return -EINVAL;



	if (epf_pf->epc || epf_vf->epc || epf_vf->epf_pf)

		return -EBUSY;



	if (epf_pf->sec_epc || epf_vf->sec_epc)

		return -EBUSY;



	mutex_lock(&epf_pf->lock);

	vfunc_no = find_first_zero_bit(&epf_pf->vfunction_num_map,

				       BITS_PER_LONG);

	if (vfunc_no >= BITS_PER_LONG) {

		mutex_unlock(&epf_pf->lock);

		return -EINVAL;

	}



	set_bit(vfunc_no, &epf_pf->vfunction_num_map);

	epf_vf->vfunc_no = vfunc_no;



	epf_vf->epf_pf = epf_pf;

	epf_vf->is_vf = true;



	list_add_tail(&epf_vf->list, &epf_pf->pci_vepf);

	mutex_unlock(&epf_pf->lock);



	return 0;

}

EXPORT_SYMBOL_GPL(pci_epf_add_vepf);



/**

 * pci_epf_remove_vepf() - remove virtual EP function from physical EP function

 * @epf_pf: the physical EP function from which the virtual EP function should

 *   be removed

 * @epf_vf: the virtual EP function to be removed

 *

 * Invoke to remove a virtual endpoint function from the physcial endpoint

 * function.

 */

void pci_epf_remove_vepf(struct pci_epf *epf_pf, struct pci_epf *epf_vf)

{

	if (IS_ERR_OR_NULL(epf_pf) || IS_ERR_OR_NULL(epf_vf))

		return;



	mutex_lock(&epf_pf->lock);

	clear_bit(epf_vf->vfunc_no, &epf_pf->vfunction_num_map);

	list_del(&epf_vf->list);

	mutex_unlock(&epf_pf->lock);

}

EXPORT_SYMBOL_GPL(pci_epf_remove_vepf);



/**

 * pci_epf_free_space() - free the allocated PCI EPF register space

 * @epf: the EPF device from whom to free the memory
@@ -317,6 +409,10 @@ struct pci_epf *pci_epf_create(const char *name) 
		return ERR_PTR(-ENOMEM);

	}



	/* VFs are numbered starting with 1. So set BIT(0) by default */

	epf->vfunction_num_map = 1;

	INIT_LIST_HEAD(&epf->pci_vepf);



	dev = &epf->dev;

	device_initialize(dev);

	dev->bus = &pci_epf_bus_type;

include/linux/pci-epf.h

+15 −1
Original line number Diff line number Diff line
@@ -121,8 +121,10 @@ struct pci_epf_bar { 
 * @bar: represents the BAR of EPF device

 * @msi_interrupts: number of MSI interrupts required by this function

 * @msix_interrupts: number of MSI-X interrupts required by this function

 * @func_no: unique function number within this endpoint device

 * @func_no: unique (physical) function number within this endpoint device

 * @vfunc_no: unique virtual function number within a physical function

 * @epc: the EPC device to which this EPF device is bound

 * @epf_pf: the physical EPF device to which this virtual EPF device is bound

 * @driver: the EPF driver to which this EPF device is bound

 * @list: to add pci_epf as a list of PCI endpoint functions to pci_epc

 * @nb: notifier block to notify EPF of any EPC events (like linkup)
@@ -133,6 +135,10 @@ struct pci_epf_bar { 
 * @sec_epc_bar: represents the BAR of EPF device associated with secondary EPC

 * @sec_epc_func_no: unique (physical) function number within the secondary EPC

 * @group: configfs group associated with the EPF device

 * @is_bound: indicates if bind notification to function driver has been invoked

 * @is_vf: true - virtual function, false - physical function

 * @vfunction_num_map: bitmap to manage virtual function number

 * @pci_vepf: list of virtual endpoint functions associated with this function

 */

struct pci_epf {

	struct device		dev;
@@ -142,8 +148,10 @@ struct pci_epf { 
	u8			msi_interrupts;

	u16			msix_interrupts;

	u8			func_no;

	u8			vfunc_no;



	struct pci_epc		*epc;

	struct pci_epf		*epf_pf;

	struct pci_epf_driver	*driver;

	struct list_head	list;

	struct notifier_block   nb;
@@ -156,6 +164,10 @@ struct pci_epf { 
	struct pci_epf_bar	sec_epc_bar[6];

	u8			sec_epc_func_no;

	struct config_group	*group;

	unsigned int		is_bound;

	unsigned int		is_vf;

	unsigned long		vfunction_num_map;

	struct list_head	pci_vepf;

};



/**
@@ -199,4 +211,6 @@ int pci_epf_bind(struct pci_epf *epf); 
void pci_epf_unbind(struct pci_epf *epf);

struct config_group *pci_epf_type_add_cfs(struct pci_epf *epf,

					  struct config_group *group);

int pci_epf_add_vepf(struct pci_epf *epf_pf, struct pci_epf *epf_vf);

void pci_epf_remove_vepf(struct pci_epf *epf_pf, struct pci_epf *epf_vf);

#endif /* __LINUX_PCI_EPF_H */