From 1cf362e907f36f104b9cf590ee6ced786226b388 Mon Sep 17 00:00:00 2001 From: Kishon Vijay Abraham I Date: Thu, 19 Aug 2021 18:03:37 +0530 Subject: 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: Hulk Robot ] Link: https://lore.kernel.org/r/20210819123343.1951-3-kishon@ti.com Signed-off-by: Kishon Vijay Abraham I Signed-off-by: Wei Yongjun Signed-off-by: Lorenzo Pieralisi --- drivers/pci/endpoint/pci-epc-core.c | 2 +- drivers/pci/endpoint/pci-epf-core.c | 98 ++++++++++++++++++++++++++++++++++++- include/linux/pci-epf.h | 16 +++++- 3 files changed, 113 insertions(+), 3 deletions(-) diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c index adec9bee72cf..01c58ca84dcc 100644 --- a/drivers/pci/endpoint/pci-epc-core.c +++ b/drivers/pci/endpoint/pci-epc-core.c @@ -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) diff --git a/drivers/pci/endpoint/pci-epf-core.c b/drivers/pci/endpoint/pci-epf-core.c index e9289d10f822..296479659aa2 100644 --- a/drivers/pci/endpoint/pci-epf-core.c +++ b/drivers/pci/endpoint/pci-epf-core.c @@ -62,13 +62,20 @@ 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); - epf->driver->ops->unbind(epf); + 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; diff --git a/include/linux/pci-epf.h b/include/linux/pci-epf.h index 2debc27ba95e..043b4c9c7188 100644 --- a/include/linux/pci-epf.h +++ b/include/linux/pci-epf.h @@ -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 */ -- cgit v1.2.3-59-g8ed1b