From: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> The current implementation of ATS, PASID, and PRI does not handle VF dependencies correctly. These are essentially Kuppuswamy's patches; I reordered and tweaked them slightly. Please treat this as a proposal, not a done deal, and post a v9 with any changes needed. Changes since v7: * Moved PRI & PASID capability offset caching to last since they're just optimizations * Cached offsets at first use instead of adding _init() functions * Dropped complicated pci_prg_resp_pasid_required() #ifdefs by just searching for the capability again * Dropped EA/VF validation since it only enforces spec language without fixing any known issues Changes since v6: * Removed locking interfaces used in v6. * Made necessary changes to PRI/PASID enable/disable calls to allow register changes only for PF. Changes since v5: * Created new patches for PRI/PASID capability caching. * Removed individual locks (pri_lock, pasid_lock) and added common resource lock to synchronize PRI/PASID updates between PF/VF. * Addressed comments from Bjorn Helgaas. Changes since v4: * Defined empty functions for pci_pri_init() and pci_pasid_init() for cases where CONFIG_PCI_PRI and CONFIG_PCI_PASID are not enabled. Changes since v3: * Fixed critical path (lock context) in pci_restore_*_state functions. Changes since v2: * Added locking mechanism to synchronize accessing PF registers in VF. * Removed spec compliance checks in patches. * Addressed comments from Bjorn Helgaas. Changes since v1: * Added more details about the patches in commit log. * Removed bulk spec check patch. * Addressed comments from Bjorn Helgaas. Link: https://lore.kernel.org/r/cover.1567029860.git.sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx v7 Kuppuswamy Sathyanarayanan (5): PCI/ATS: Handle sharing of PF PRI Capability with all VFs PCI/ATS: Handle sharing of PF PASID Capability with all VFs PCI/ATS: Disable PF/VF ATS service independently PCI/ATS: Cache PRI Capability offset PCI/ATS: Cache PASID Capability offset drivers/pci/ats.c | 153 +++++++++++++++++++++++++++----------------- include/linux/pci.h | 3 +- 2 files changed, 96 insertions(+), 60 deletions(-) -- 2.23.0.187.g17f5b7556c-goog
