kernel.git/drivers/pci/msi.c, branch linux-5.5.y

PCI/MSI: Fix incorrect MSI-X masking on resume

2019-11-26T19:10:29Z

When a driver enables MSI-X, msix_program_entries() reads the MSI-X Vector Control register for each vector and saves it in desc->masked. Each register is 32 bits and bit 0 is the actual Mask bit. When we restored these registers during resume, we previously set the Mask bit if *any* bit in desc->masked was set instead of when the Mask bit itself was set: pci_restore_state pci_restore_msi_state __pci_restore_msix_state for_each_pci_msi_entry msix_mask_irq(entry, entry->masked) <-- entire u32 word __pci_msix_desc_mask_irq(desc, flag) mask_bits = desc->masked & ~PCI_MSIX_ENTRY_CTRL_MASKBIT if (flag) <-- testing entire u32, not just bit 0 mask_bits |= PCI_MSIX_ENTRY_CTRL_MASKBIT writel(mask_bits, desc_addr + PCI_MSIX_ENTRY_VECTOR_CTRL) This means that after resume, MSI-X vectors were masked when they shouldn't be, which leads to timeouts like this: nvme nvme0: I/O 978 QID 3 timeout, completion polled On resume, set the Mask bit only when the saved Mask bit from suspend was set. This should remove the need for 19ea025e1d28 ("nvme: Add quirk for Kingston NVME SSD running FW E8FK11.T"). [bhelgaas: commit log, move fix to __pci_msix_desc_mask_irq()] Link: https://bugzilla.kernel.org/show_bug.cgi?id=204887 Link: https://lore.kernel.org/r/20191008034238.2503-1-jian-hong@endlessm.com Fixes: f2440d9acbe8 ("PCI MSI: Refactor interrupt masking code") Signed-off-by: Jian-Hong Pan Signed-off-by: Bjorn Helgaas Cc: stable@vger.kernel.org

PCI/MSI: Move power state check out of pci_msi_supported()

2019-11-26T19:10:28Z

27e20603c54b ("PCI/MSI: Move D0 check into pci_msi_check_device()") moved the power state check into pci_msi_check_device(), which was subsequently renamed to pci_msi_supported(). This didn't change the behavior, since both callers checked the power state. However, it doesn't fit the current "pci_msi_supported()" name, which should return what the device is capable of, independent of the power state. Move the power state check back into the callers for readability. No functional change intended. Signed-off-by: Bjorn Helgaas Reviewed-by: Rafael J. Wysocki

PCI/MSI: Remove unused pci_irq_get_node()

2019-11-26T19:10:27Z

The function pci_irq_get_node() is not used by anyone in the tree, so just delete it. Link: https://lore.kernel.org/r/20191014100452.GA6699@kroah.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Bjorn Helgaas Reviewed-by: Andrew Murray

Merge tag 'ntb-5.3' of git://github.com/jonmason/ntb

2019-07-21T16:46:59Z

Pull NTB updates from Jon Mason: "New feature to add support for NTB virtual MSI interrupts, the ability to test and use this feature in the NTB transport layer. Also, bug fixes for the AMD and Switchtec drivers, as well as some general patches" * tag 'ntb-5.3' of git://github.com/jonmason/ntb: (22 commits) NTB: Describe the ntb_msi_test client in the documentation. NTB: Add MSI interrupt support to ntb_transport NTB: Add ntb_msi_test support to ntb_test NTB: Introduce NTB MSI Test Client NTB: Introduce MSI library NTB: Rename ntb.c to support multiple source files in the module NTB: Introduce functions to calculate multi-port resource index NTB: Introduce helper functions to calculate logical port number PCI/switchtec: Add module parameter to request more interrupts PCI/MSI: Support allocating virtual MSI interrupts ntb_hw_switchtec: Fix setup MW with failure bug ntb_hw_switchtec: Skip unnecessary re-setup of shared memory window for crosslink case ntb_hw_switchtec: Remove redundant steps of switchtec_ntb_reinit_peer() function NTB: correct ntb_dev_ops and ntb_dev comment typos NTB: amd: Silence shift wrapping warning in amd_ntb_db_vector_mask() ntb_hw_switchtec: potential shift wrapping bug in switchtec_ntb_init_sndev() NTB: ntb_transport: Ensure qp->tx_mw_dma_addr is initaliazed NTB: ntb_hw_amd: set peer limit register NTB: ntb_perf: Clear stale values in doorbell and command SPAD register NTB: ntb_perf: Disable NTB link after clearing peer XLAT registers ...

PCI: Fix typos and whitespace errors

2019-07-09T12:24:53Z

Fix typos in drivers/pci. Comment and whitespace changes only. Signed-off-by: Bjorn Helgaas Reviewed-by: Rafael J. Wysocki Reviewed-by: Randy Dunlap

PCI/MSI: Support allocating virtual MSI interrupts

2019-06-13T12:59:34Z

For NTB devices, we want to be able to trigger MSI interrupts through a memory window. In these cases we may want to use more interrupts than the NTB PCI device has available in its MSI-X table. We allow for this by creating a new 'virtual' interrupt. These interrupts are allocated as usual but are not programmed into the MSI-X table (as there may not be space for them). The MSI address and data will then handled through an NTB MSI library introduced later in this series. Signed-off-by: Logan Gunthorpe Acked-by: Bjorn Helgaas Signed-off-by: Jon Mason

PCI: Add pci_dev_id() helper

2019-04-29T21:12:05Z

In several places in the kernel we find PCI_DEVID used like this: PCI_DEVID(dev->bus->number, dev->devfn) Add a "pci_dev_id(struct pci_dev *dev)" helper to simplify callers. Signed-off-by: Heiner Kallweit Signed-off-by: Bjorn Helgaas

PCI/MSI: Remove obsolete sanity checks for multiple interrupt sets

2019-02-18T10:21:29Z

Multiple interrupt sets for affinity spreading are now handled in the core code and the number of sets and their size is recalculated via a driver supplied callback. That avoids the requirement to invoke pci_alloc_irq_vectors_affinity() with the arguments minvecs and maxvecs set to the same value and the callsite handling the ENOSPC situation. Remove the now obsolete sanity checks and the related comments. Signed-off-by: Thomas Gleixner Reviewed-by: Ming Lei Acked-by: Marc Zyngier Cc: Christoph Hellwig Cc: Bjorn Helgaas Cc: Jens Axboe Cc: linux-block@vger.kernel.org Cc: Sagi Grimberg Cc: linux-nvme@lists.infradead.org Cc: linux-pci@vger.kernel.org Cc: Keith Busch Cc: Sumit Saxena Cc: Kashyap Desai Cc: Shivasharan Srikanteshwara Link: https://lkml.kernel.org/r/20190216172228.778630549@linutronix.de

genirq/affinity: Add new callback for (re)calculating interrupt sets

2019-02-18T10:21:28Z

The interrupt affinity spreading mechanism supports to spread out affinities for one or more interrupt sets. A interrupt set contains one or more interrupts. Each set is mapped to a specific functionality of a device, e.g. general I/O queues and read I/O queus of multiqueue block devices. The number of interrupts per set is defined by the driver. It depends on the total number of available interrupts for the device, which is determined by the PCI capabilites and the availability of underlying CPU resources, and the number of queues which the device provides and the driver wants to instantiate. The driver passes initial configuration for the interrupt allocation via a pointer to struct irq_affinity. Right now the allocation mechanism is complex as it requires to have a loop in the driver to determine the maximum number of interrupts which are provided by the PCI capabilities and the underlying CPU resources. This loop would have to be replicated in every driver which wants to utilize this mechanism. That's unwanted code duplication and error prone. In order to move this into generic facilities it is required to have a mechanism, which allows the recalculation of the interrupt sets and their size, in the core code. As the core code does not have any knowledge about the underlying device, a driver specific callback is required in struct irq_affinity, which can be invoked by the core code. The callback gets the number of available interupts as an argument, so the driver can calculate the corresponding number and size of interrupt sets. At the moment the struct irq_affinity pointer which is handed in from the driver and passed through to several core functions is marked 'const', but for the callback to be able to modify the data in the struct it's required to remove the 'const' qualifier. Add the optional callback to struct irq_affinity, which allows drivers to recalculate the number and size of interrupt sets and remove the 'const' qualifier. For simple invocations, which do not supply a callback, a default callback is installed, which just sets nr_sets to 1 and transfers the number of spreadable vectors to the set_size array at index 0. This is for now guarded by a check for nr_sets != 0 to keep the NVME driver working until it is converted to the callback mechanism. To make sure that the driver configuration is correct under all circumstances the callback is invoked even when there are no interrupts for queues left, i.e. the pre/post requirements already exhaust the numner of available interrupts. At the PCI layer irq_create_affinity_masks() has to be invoked even for the case where the legacy interrupt is used. That ensures that the callback is invoked and the device driver can adjust to that situation. [ tglx: Fixed the simple case (no sets required). Moved the sanity check for nr_sets after the invocation of the callback so it catches broken drivers. Fixed the kernel doc comments for struct irq_affinity and de-'This patch'-ed the changelog ] Signed-off-by: Ming Lei Signed-off-by: Thomas Gleixner Acked-by: Marc Zyngier Cc: Christoph Hellwig Cc: Bjorn Helgaas Cc: Jens Axboe Cc: linux-block@vger.kernel.org Cc: Sagi Grimberg Cc: linux-nvme@lists.infradead.org Cc: linux-pci@vger.kernel.org Cc: Keith Busch Cc: Sumit Saxena Cc: Kashyap Desai Cc: Shivasharan Srikanteshwara Link: https://lkml.kernel.org/r/20190216172228.512444498@linutronix.de

PCI/MSI: Return -ENOSPC from pci_alloc_irq_vectors_affinity()

2019-01-15T23:31:29Z

The API of pci_alloc_irq_vectors_affinity() says it returns -ENOSPC if fewer than @min_vecs interrupt vectors are available for @dev. However, if a device supports MSI-X but not MSI and a caller requests @min_vecs that can't be satisfied by MSI-X, we previously returned -EINVAL (from the failed attempt to enable MSI), not -ENOSPC. When -ENOSPC is returned, callers may reduce the number IRQs they request and try again. Most callers can use the @min_vecs and @max_vecs parameters to avoid this retry loop, but that doesn't work when using IRQ affinity "nr_sets" because rebalancing the sets is driver-specific. This return value bug has been present since pci_alloc_irq_vectors() was added in v4.10 by aff171641d18 ("PCI: Provide sensible IRQ vector alloc/free routines"), but it wasn't an issue because @min_vecs/@max_vecs removed the need for callers to iteratively reduce the number of IRQs requested and retry the allocation, so they didn't need to distinguish -ENOSPC from -EINVAL. In v5.0, 6da4b3ab9a6e ("genirq/affinity: Add support for allocating interrupt sets") added IRQ sets to the interface, which reintroduced the need to check for -ENOSPC and possibly reduce the number of IRQs requested and retry the allocation. Signed-off-by: Ming Lei [bhelgaas: changelog] Signed-off-by: Bjorn Helgaas Cc: Jens Axboe Cc: Keith Busch Cc: Christoph Hellwig