From: Kishon Vijay Abraham I commit 2499ee84e02774a8573b7b4c76c8f2ea38669313 upstream. The PCIe endpoint core relies on the drivers that invoke the pci_epc_add_epf() API to allocate and assign a function number to each physical function (PF). Since endpoint function device can be created by multiple mechanisms (configfs, devicetree, etc..), allowing each of these mechanisms to assign a function number would result in mutliple endpoint function devices having the same function number. In order to avoid this, let EPC core assign a function number to the endpoint device. Signed-off-by: Kishon Vijay Abraham I Signed-off-by: Lorenzo Pieralisi Signed-off-by: Lad Prabhakar --- drivers/pci/endpoint/pci-ep-cfs.c | 27 +++++---------------------- drivers/pci/endpoint/pci-epc-core.c | 26 ++++++++++++++++++++++---- include/linux/pci-epc.h | 2 ++ 3 files changed, 29 insertions(+), 26 deletions(-) diff --git a/drivers/pci/endpoint/pci-ep-cfs.c b/drivers/pci/endpoint/pci-ep-cfs.c index d1288a0bd530..e7e8367eead1 100644 --- a/drivers/pci/endpoint/pci-ep-cfs.c +++ b/drivers/pci/endpoint/pci-ep-cfs.c @@ -29,7 +29,6 @@ struct pci_epc_group { struct config_group group; struct pci_epc *epc; bool start; - unsigned long function_num_map; }; static inline struct pci_epf_group *to_pci_epf_group(struct config_item *item) @@ -89,37 +88,22 @@ static int pci_epc_epf_link(struct config_item *epc_item, struct config_item *epf_item) { int ret; - u32 func_no = 0; struct pci_epf_group *epf_group = to_pci_epf_group(epf_item); struct pci_epc_group *epc_group = to_pci_epc_group(epc_item); struct pci_epc *epc = epc_group->epc; struct pci_epf *epf = epf_group->epf; - func_no = find_first_zero_bit(&epc_group->function_num_map, - BITS_PER_LONG); - if (func_no >= BITS_PER_LONG) - return -EINVAL; - - set_bit(func_no, &epc_group->function_num_map); - epf->func_no = func_no; - ret = pci_epc_add_epf(epc, epf); if (ret) - goto err_add_epf; + return ret; ret = pci_epf_bind(epf); - if (ret) - goto err_epf_bind; + if (ret) { + pci_epc_remove_epf(epc, epf); + return ret; + } return 0; - -err_epf_bind: - pci_epc_remove_epf(epc, epf); - -err_add_epf: - clear_bit(func_no, &epc_group->function_num_map); - - return ret; } static void pci_epc_epf_unlink(struct config_item *epc_item, @@ -134,7 +118,6 @@ static void pci_epc_epf_unlink(struct config_item *epc_item, epc = epc_group->epc; epf = epf_group->epf; - clear_bit(epf->func_no, &epc_group->function_num_map); pci_epf_unbind(epf); pci_epc_remove_epf(epc, epf); } diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c index e51a12ed85bb..dc1c673534e0 100644 --- a/drivers/pci/endpoint/pci-epc-core.c +++ b/drivers/pci/endpoint/pci-epc-core.c @@ -471,22 +471,39 @@ EXPORT_SYMBOL_GPL(pci_epc_write_header); */ int pci_epc_add_epf(struct pci_epc *epc, struct pci_epf *epf) { + u32 func_no; + int ret = 0; + if (epf->epc) return -EBUSY; if (IS_ERR(epc)) return -EINVAL; - if (epf->func_no > epc->max_functions - 1) - return -EINVAL; + mutex_lock(&epc->lock); + func_no = find_first_zero_bit(&epc->function_num_map, + BITS_PER_LONG); + if (func_no >= BITS_PER_LONG) { + ret = -EINVAL; + goto ret; + } + + if (func_no > epc->max_functions - 1) { + dev_err(&epc->dev, "Exceeding max supported Function Number\n"); + ret = -EINVAL; + goto ret; + } + set_bit(func_no, &epc->function_num_map); + epf->func_no = func_no; epf->epc = epc; - mutex_lock(&epc->lock); list_add_tail(&epf->list, &epc->pci_epf); + +ret: mutex_unlock(&epc->lock); - return 0; + return ret; } EXPORT_SYMBOL_GPL(pci_epc_add_epf); @@ -503,6 +520,7 @@ void pci_epc_remove_epf(struct pci_epc *epc, struct pci_epf *epf) return; mutex_lock(&epc->lock); + clear_bit(epf->func_no, &epc->function_num_map); list_del(&epf->list); epf->epc = NULL; mutex_unlock(&epc->lock); diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h index 9b21692bc2e4..44bfbeb480bb 100644 --- a/include/linux/pci-epc.h +++ b/include/linux/pci-epc.h @@ -92,6 +92,7 @@ struct pci_epc_mem { * @max_functions: max number of functions that can be configured in this EPC * @group: configfs group representing the PCI EPC device * @lock: mutex to protect pci_epc ops + * @function_num_map: bitmap to manage physical function number * @notifier: used to notify EPF of any EPC events (like linkup) */ struct pci_epc { @@ -103,6 +104,7 @@ struct pci_epc { struct config_group *group; /* mutex to protect against concurrent access of EP controller */ struct mutex lock; + unsigned long function_num_map; struct atomic_notifier_head notifier; }; -- 2.17.1