On Thu, Aug 01, 2019 at 05:06:00PM -0700, [email protected] wrote: > From: Kuppuswamy Sathyanarayanan <[email protected]> > > Currently, PASID Capability checks are repeated across all PASID API's. > Instead, cache the capability check result in pci_pasid_init() and use > it in other PASID API's. Also, since PASID is a shared resource between > PF/VF, initialize PASID features with default values in pci_pasid_init().
Split into two patches as for PRI. > Signed-off-by: Kuppuswamy Sathyanarayanan > <[email protected]> > --- > drivers/pci/ats.c | 74 +++++++++++++++++++++++++++++------------ > include/linux/pci-ats.h | 5 +++ > include/linux/pci.h | 1 + > 3 files changed, 59 insertions(+), 21 deletions(-) > > diff --git a/drivers/pci/ats.c b/drivers/pci/ats.c > index 280be911f190..1f4be27a071d 100644 > --- a/drivers/pci/ats.c > +++ b/drivers/pci/ats.c > @@ -30,6 +30,8 @@ void pci_ats_init(struct pci_dev *dev) > dev->ats_cap = pos; > > pci_pri_init(dev); > + Superfluous blank line; you can remove it. > + pci_pasid_init(dev); > } > > /** > @@ -315,6 +317,40 @@ EXPORT_SYMBOL_GPL(pci_reset_pri); > #endif /* CONFIG_PCI_PRI */ > > #ifdef CONFIG_PCI_PASID > + > +void pci_pasid_init(struct pci_dev *pdev) > +{ > + u16 supported; > + int pos; > + > + /* > + * As per PCIe r4.0, sec 9.3.7.14, only PF is permitted to > + * implement PASID Capability and all associated VFs can > + * only use it. Since PF already initialized the PASID > + * parameters there is no need to proceed further. > + */ > + if (pdev->is_virtfn) > + return; > + > + pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID); > + if (!pos) > + return; > + > + pci_read_config_word(pdev, pos + PCI_PASID_CAP, &supported); > + > + supported &= PCI_PASID_CAP_EXEC | PCI_PASID_CAP_PRIV; > + > + /* > + * Enable all supported features. Since PASID is a shared > + * resource between PF/VF, we must not set this feature as > + * a per device property in pci_enable_pasid(). But pci_enable_pasid() *does* set PCI_PASID_CTRL. Either the comments or the code needs to be updated. > + */ > + pci_write_config_word(pdev, pos + PCI_PASID_CTRL, supported); > + > + pdev->pasid_features = supported; > + pdev->pasid_cap = pos; > +} > + > /** > * pci_enable_pasid - Enable the PASID capability > * @pdev: PCI device structure > @@ -323,11 +359,13 @@ EXPORT_SYMBOL_GPL(pci_reset_pri); > * Returns 0 on success, negative value on error. This function checks > * whether the features are actually supported by the device and returns > * an error if not. > + * > + * TODO: Since PASID is a shared resource between PF/VF, don't update > + * PASID features in the same API as a per device feature. > */ > int pci_enable_pasid(struct pci_dev *pdev, int features) > { > u16 control, supported; > - int pos; > > if (WARN_ON(pdev->pasid_enabled)) > return -EBUSY; > @@ -335,11 +373,11 @@ 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 (!pdev->pasid_cap) > return -EINVAL; > > - pci_read_config_word(pdev, pos + PCI_PASID_CAP, &supported); > + pci_read_config_word(pdev, pdev->pasid_cap + PCI_PASID_CAP, > + &supported); > supported &= PCI_PASID_CAP_EXEC | PCI_PASID_CAP_PRIV; > > /* User wants to enable anything unsupported? */ > @@ -349,7 +387,7 @@ 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, pdev->pasid_cap + PCI_PASID_CTRL, control); > > pdev->pasid_enabled = 1; > > @@ -364,16 +402,14 @@ EXPORT_SYMBOL_GPL(pci_enable_pasid); > void pci_disable_pasid(struct pci_dev *pdev) > { > u16 control = 0; > - int pos; > > if (WARN_ON(!pdev->pasid_enabled)) > return; > > - pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID); > - if (!pos) > + if (!pdev->pasid_cap) > return; > > - pci_write_config_word(pdev, pos + PCI_PASID_CTRL, control); > + pci_write_config_word(pdev, pdev->pasid_cap + PCI_PASID_CTRL, control); > > pdev->pasid_enabled = 0; > } > @@ -386,17 +422,15 @@ EXPORT_SYMBOL_GPL(pci_disable_pasid); > void pci_restore_pasid_state(struct pci_dev *pdev) > { > u16 control; > - int pos; > > if (!pdev->pasid_enabled) > return; > > - pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID); > - if (!pos) > + if (!pdev->pasid_cap) > return; > > control = PCI_PASID_CTRL_ENABLE | pdev->pasid_features; > - pci_write_config_word(pdev, pos + PCI_PASID_CTRL, control); > + pci_write_config_word(pdev, pdev->pasid_cap + PCI_PASID_CTRL, control); > } > EXPORT_SYMBOL_GPL(pci_restore_pasid_state); > > @@ -413,13 +447,12 @@ EXPORT_SYMBOL_GPL(pci_restore_pasid_state); > int pci_pasid_features(struct pci_dev *pdev) > { > u16 supported; > - int pos; > > - pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID); > - if (!pos) > + if (!pdev->pasid_cap) > return -EINVAL; > > - pci_read_config_word(pdev, pos + PCI_PASID_CAP, &supported); > + pci_read_config_word(pdev, pdev->pasid_cap + PCI_PASID_CAP, > + &supported); > > supported &= PCI_PASID_CAP_EXEC | PCI_PASID_CAP_PRIV; > > @@ -469,13 +502,12 @@ EXPORT_SYMBOL_GPL(pci_prg_resp_pasid_required); > int pci_max_pasids(struct pci_dev *pdev) > { > u16 supported; > - int pos; > > - pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID); > - if (!pos) > + if (!pdev->pasid_cap) > return -EINVAL; > > - pci_read_config_word(pdev, pos + PCI_PASID_CAP, &supported); > + pci_read_config_word(pdev, pdev->pasid_cap + PCI_PASID_CAP, > + &supported); > > supported = (supported & PASID_NUMBER_MASK) >> PASID_NUMBER_SHIFT; > > diff --git a/include/linux/pci-ats.h b/include/linux/pci-ats.h > index 33653d4ca94f..bc7f815d38ff 100644 > --- a/include/linux/pci-ats.h > +++ b/include/linux/pci-ats.h > @@ -40,6 +40,7 @@ static inline int pci_reset_pri(struct pci_dev *pdev) > > #ifdef CONFIG_PCI_PASID > > +void pci_pasid_init(struct pci_dev *pdev); Move to drivers/pci/pci.h. > int pci_enable_pasid(struct pci_dev *pdev, int features); > void pci_disable_pasid(struct pci_dev *pdev); > void pci_restore_pasid_state(struct pci_dev *pdev); > @@ -48,6 +49,10 @@ int pci_max_pasids(struct pci_dev *pdev); > > #else /* CONFIG_PCI_PASID */ > > +static inline void pci_pasid_init(struct pci_dev *pdev) > +{ > +} > + > static inline int pci_enable_pasid(struct pci_dev *pdev, int features) > { > return -EINVAL; > diff --git a/include/linux/pci.h b/include/linux/pci.h > index 56b55db099fc..27224c0db849 100644 > --- a/include/linux/pci.h > +++ b/include/linux/pci.h > @@ -459,6 +459,7 @@ 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 > -- > 2.21.0 >
