From 751035b8dc061ae434c3311bac9cd6d0e5e00f94 Mon Sep 17 00:00:00 2001 From: Kuppuswamy Sathyanarayanan Date: Thu, 5 Sep 2019 14:31:46 -0500 Subject: [PATCH] PCI/ATS: Cache PASID Capability offset Previously each PASID interface searched for the PASID Capability. Cache the capability offset the first time we use it instead of searching each time. [bhelgaas: commit log, reorder patch to later, call pci_pasid_init() from pci_init_capabilities()] Link: https://lore.kernel.org/r/4957778959fa34eab3e8b3065d1951989c61cb0f.1567029860.git.sathyanarayanan.kuppuswamy@linux.intel.com Link: https://lore.kernel.org/r/20190905193146.90250-6-helgaas@kernel.org Signed-off-by: Kuppuswamy Sathyanarayanan Signed-off-by: Bjorn Helgaas --- drivers/pci/ats.c | 42 +++++++++++++++++++++--------------------- drivers/pci/pci.h | 6 ++++++ drivers/pci/probe.c | 3 +++ include/linux/pci.h | 1 + 4 files changed, 31 insertions(+), 21 deletions(-) diff --git a/drivers/pci/ats.c b/drivers/pci/ats.c index c97e862..d5ac808 100644 --- a/drivers/pci/ats.c +++ b/drivers/pci/ats.c @@ -322,6 +322,11 @@ EXPORT_SYMBOL_GPL(pci_prg_resp_pasid_required); #endif /* CONFIG_PCI_PRI */ #ifdef CONFIG_PCI_PASID +void pci_pasid_init(struct pci_dev *pdev) +{ + pdev->pasid_cap = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID); +} + /** * pci_enable_pasid - Enable the PASID capability * @pdev: PCI device structure @@ -334,7 +339,7 @@ EXPORT_SYMBOL_GPL(pci_prg_resp_pasid_required); int pci_enable_pasid(struct pci_dev *pdev, int features) { u16 control, supported; - int pos; + int pasid = pdev->pasid_cap; /* * VFs must not implement the PASID Capability, but if a PF @@ -352,11 +357,10 @@ int pci_enable_pasid(struct pci_dev *pdev, int features) if (!pdev->eetlp_prefix_path) return -EINVAL; - pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID); - if (!pos) + if (!pasid) return -EINVAL; - pci_read_config_word(pdev, pos + PCI_PASID_CAP, &supported); + pci_read_config_word(pdev, pasid + PCI_PASID_CAP, &supported); supported &= PCI_PASID_CAP_EXEC | PCI_PASID_CAP_PRIV; /* User wants to enable anything unsupported? */ @@ -366,7 +370,7 @@ int pci_enable_pasid(struct pci_dev *pdev, int features) control = PCI_PASID_CTRL_ENABLE | features; pdev->pasid_features = features; - pci_write_config_word(pdev, pos + PCI_PASID_CTRL, control); + pci_write_config_word(pdev, pasid + PCI_PASID_CTRL, control); pdev->pasid_enabled = 1; @@ -381,7 +385,7 @@ EXPORT_SYMBOL_GPL(pci_enable_pasid); void pci_disable_pasid(struct pci_dev *pdev) { u16 control = 0; - int pos; + int pasid = pdev->pasid_cap; /* VFs share the PF PASID configuration */ if (pdev->is_virtfn) @@ -390,11 +394,10 @@ void pci_disable_pasid(struct pci_dev *pdev) if (WARN_ON(!pdev->pasid_enabled)) return; - pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID); - if (!pos) + if (!pasid) return; - pci_write_config_word(pdev, pos + PCI_PASID_CTRL, control); + pci_write_config_word(pdev, pasid + PCI_PASID_CTRL, control); pdev->pasid_enabled = 0; } @@ -407,7 +410,7 @@ EXPORT_SYMBOL_GPL(pci_disable_pasid); void pci_restore_pasid_state(struct pci_dev *pdev) { u16 control; - int pos; + int pasid = pdev->pasid_cap; if (pdev->is_virtfn) return; @@ -415,12 +418,11 @@ void pci_restore_pasid_state(struct pci_dev *pdev) if (!pdev->pasid_enabled) return; - pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID); - if (!pos) + if (!pasid) return; control = PCI_PASID_CTRL_ENABLE | pdev->pasid_features; - pci_write_config_word(pdev, pos + PCI_PASID_CTRL, control); + pci_write_config_word(pdev, pasid + PCI_PASID_CTRL, control); } EXPORT_SYMBOL_GPL(pci_restore_pasid_state); @@ -437,16 +439,15 @@ EXPORT_SYMBOL_GPL(pci_restore_pasid_state); int pci_pasid_features(struct pci_dev *pdev) { u16 supported; - int pos; + int pasid = pdev->pasid_cap; if (pdev->is_virtfn) pdev = pci_physfn(pdev); - pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID); - if (!pos) + if (!pasid) return -EINVAL; - pci_read_config_word(pdev, pos + PCI_PASID_CAP, &supported); + pci_read_config_word(pdev, pasid + PCI_PASID_CAP, &supported); supported &= PCI_PASID_CAP_EXEC | PCI_PASID_CAP_PRIV; @@ -466,16 +467,15 @@ EXPORT_SYMBOL_GPL(pci_pasid_features); int pci_max_pasids(struct pci_dev *pdev) { u16 supported; - int pos; + int pasid = pdev->pasid_cap; if (pdev->is_virtfn) pdev = pci_physfn(pdev); - pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID); - if (!pos) + if (!pasid) return -EINVAL; - pci_read_config_word(pdev, pos + PCI_PASID_CAP, &supported); + pci_read_config_word(pdev, pasid + PCI_PASID_CAP, &supported); supported = (supported & PASID_NUMBER_MASK) >> PASID_NUMBER_SHIFT; diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index aa08cd3..ae84d28 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -462,6 +462,12 @@ void pci_pri_init(struct pci_dev *dev); static inline void pci_pri_init(struct pci_dev *dev) { } #endif +#ifdef CONFIG_PCI_PASID +void pci_pasid_init(struct pci_dev *dev); +#else +static inline void pci_pasid_init(struct pci_dev *dev) { } +#endif + #ifdef CONFIG_PCI_IOV int pci_iov_init(struct pci_dev *dev); void pci_iov_release(struct pci_dev *dev); diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index d145165..df2b778 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -2327,6 +2327,9 @@ static void pci_init_capabilities(struct pci_dev *dev) /* Page Request Interface */ pci_pri_init(dev); + /* Process Address Space ID */ + pci_pasid_init(dev); + /* Enable ACS P2P upstream forwarding */ pci_enable_acs(dev); diff --git a/include/linux/pci.h b/include/linux/pci.h index e7770d9..6542100 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -458,6 +458,7 @@ struct pci_dev { u32 pri_reqs_alloc; /* Number of PRI requests allocated */ #endif #ifdef CONFIG_PCI_PASID + u16 pasid_cap; /* PASID Capability offset */ u16 pasid_features; #endif #ifdef CONFIG_PCI_P2PDMA -- 2.7.4