Add a dev_flags bit, PCI_DEV_FLAGS_VPD_REF_F0, to access VPD through function 0 to provide VPD access on other functions. This solves concurrent access problems on many devices without changing the attributes exposed in sysfs. Never set this bit on function 0 or there will be an infinite recursion. Signed-off-by: Mark Rustad <mark.d.rustad@xxxxxxxxx> --- Changes in V2: - Corrected spelling in log message - Added checks to see that the referenced function 0 is reasonable --- drivers/pci/access.c | 48 +++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 47 insertions(+), 1 deletion(-) diff --git a/drivers/pci/access.c b/drivers/pci/access.c index d9b64a175990..74634d4868a2 100644 --- a/drivers/pci/access.c +++ b/drivers/pci/access.c @@ -439,6 +439,40 @@ static const struct pci_vpd_ops pci_vpd_pci22_ops = { .release = pci_vpd_pci22_release, }; +static ssize_t pci_vpd_f0_read(struct pci_dev *dev, loff_t pos, size_t count, + void *arg) +{ + struct pci_dev *tdev = pci_get_slot(dev->bus, PCI_SLOT(dev->devfn)); + ssize_t ret; + + if (!tdev) + return -ENODEV; + + ret = pci_read_vpd(tdev, pos, count, arg); + pci_dev_put(tdev); + return ret; +} + +static ssize_t pci_vpd_f0_write(struct pci_dev *dev, loff_t pos, size_t count, + const void *arg) +{ + struct pci_dev *tdev = pci_get_slot(dev->bus, PCI_SLOT(dev->devfn)); + ssize_t ret; + + if (!tdev) + return -ENODEV; + + ret = pci_write_vpd(tdev, pos, count, arg); + pci_dev_put(tdev); + return ret; +} + +static const struct pci_vpd_ops pci_vpd_f0_ops = { + .read = pci_vpd_f0_read, + .write = pci_vpd_f0_write, + .release = pci_vpd_pci22_release, +}; + int pci_vpd_pci22_init(struct pci_dev *dev) { struct pci_vpd_pci22 *vpd; @@ -447,12 +481,24 @@ int pci_vpd_pci22_init(struct pci_dev *dev) cap = pci_find_capability(dev, PCI_CAP_ID_VPD); if (!cap) return -ENODEV; + if (dev->dev_flags & PCI_DEV_FLAGS_VPD_REF_F0) { + struct pci_dev *tdev; + + tdev = pci_get_slot(dev->bus, PCI_SLOT(dev->devfn)); + if (!tdev || !dev->multifunction || !tdev->multifunction || + dev->class != tdev->class || dev->vendor != tdev->vendor || + dev->device != tdev->device) + return -ENODEV; + } vpd = kzalloc(sizeof(*vpd), GFP_ATOMIC); if (!vpd) return -ENOMEM; vpd->base.len = PCI_VPD_PCI22_SIZE; - vpd->base.ops = &pci_vpd_pci22_ops; + if (dev->dev_flags & PCI_DEV_FLAGS_VPD_REF_F0) + vpd->base.ops = &pci_vpd_f0_ops; + else + vpd->base.ops = &pci_vpd_pci22_ops; mutex_init(&vpd->lock); vpd->cap = cap; vpd->busy = false; diff --git a/include/linux/pci.h b/include/linux/pci.h index 353db8dc4c6e..194df6d635e6 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -180,6 +180,8 @@ enum pci_dev_flags { PCI_DEV_FLAGS_NO_BUS_RESET = (__force pci_dev_flags_t) (1 << 6), /* Do not use PM reset even if device advertises NoSoftRst- */ PCI_DEV_FLAGS_NO_PM_RESET = (__force pci_dev_flags_t) (1 << 7), + /* Get VPD from function 0 VPD */ + PCI_DEV_FLAGS_VPD_REF_F0 = (__force pci_dev_flags_t) (1 << 8), }; enum pci_irq_reroute_variant { -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html