[PATCH V3 3/6] PCI: Unify try slot and bus reset API
From: Sinan Kaya <hidden>
Date: 2018-06-28 18:30:18
Also in:
kvm, linux-arm-msm, linux-pci, lkml
Subsystem:
pci subsystem, the rest, vfio driver · Maintainers:
Bjorn Helgaas, Linus Torvalds, Alex Williamson
Drivers are expected to call pci_try_reset_slot() or pci_try_reset_bus() by querying if a system supports hotplug or not. A survey showed that most drivers don't do this and we are leaking hotplug capability to the user. Hide pci_try_slot_reset() from drivers and embed into pci_try_bus_reset(). Change pci_try_reset_bus() parameter from struct pci_bus to struct pci_dev. Signed-off-by: Sinan Kaya <redacted> --- drivers/pci/pci.c | 26 +++++++++++++++++++++----- drivers/vfio/pci/vfio_pci.c | 6 ++---- include/linux/pci.h | 3 +-- 3 files changed, 24 insertions(+), 11 deletions(-)
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 236220c..79a1566 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c@@ -4817,12 +4817,12 @@ int pci_reset_slot(struct pci_slot *slot) EXPORT_SYMBOL_GPL(pci_reset_slot); /** - * pci_try_reset_slot - Try to reset a PCI slot + * __pci_try_reset_slot - Try to reset a PCI slot * @slot: PCI slot to reset * * Same as above except return -EAGAIN if the slot cannot be locked */ -int pci_try_reset_slot(struct pci_slot *slot) +static int __pci_try_reset_slot(struct pci_slot *slot) { int rc;
@@ -4843,7 +4843,6 @@ int pci_try_reset_slot(struct pci_slot *slot) return rc; } -EXPORT_SYMBOL_GPL(pci_try_reset_slot); static int pci_bus_reset(struct pci_bus *bus, int probe) {
@@ -4906,12 +4905,12 @@ int pci_reset_bus(struct pci_bus *bus) EXPORT_SYMBOL_GPL(pci_reset_bus); /** - * pci_try_reset_bus - Try to reset a PCI bus + * __pci_try_reset_bus - Try to reset a PCI bus * @bus: top level PCI bus to reset * * Same as above except return -EAGAIN if the bus cannot be locked */ -int pci_try_reset_bus(struct pci_bus *bus) +static int __pci_try_reset_bus(struct pci_bus *bus) { int rc;
@@ -4932,6 +4931,23 @@ int pci_try_reset_bus(struct pci_bus *bus) return rc; } + +/** + * pci_try_reset_bus - Try to reset a PCI bus + * @pdev: top level PCI device to reset via slot/bus + * + * Same as above except return -EAGAIN if the bus cannot be locked + */ +int pci_try_reset_bus(struct pci_dev *pdev) +{ + bool slot = false; + + if (!pci_probe_reset_slot(pdev->slot)) + slot = true; + + return slot ? __pci_try_reset_slot(pdev->slot) : + __pci_try_reset_bus(pdev->bus); +} EXPORT_SYMBOL_GPL(pci_try_reset_bus); /**
diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
index b423a30..71018ec 100644
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c@@ -1010,8 +1010,7 @@ static long vfio_pci_ioctl(void *device_data, &info, slot); if (!ret) /* User has access, do the reset */ - ret = slot ? pci_try_reset_slot(vdev->pdev->slot) : - pci_try_reset_bus(vdev->pdev->bus); + ret = pci_try_reset_bus(vdev->pdev); hot_reset_release: for (i--; i >= 0; i--)
@@ -1373,8 +1372,7 @@ static void vfio_pci_try_bus_reset(struct vfio_pci_device *vdev) } if (needs_reset) - ret = slot ? pci_try_reset_slot(vdev->pdev->slot) : - pci_try_reset_bus(vdev->pdev->bus); + ret = pci_try_reset_bus(vdev->pdev); put_devs: for (i = 0; i < devs.cur_index; i++) {
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 6b12ce2..f5c85b6 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h@@ -1096,10 +1096,9 @@ int pci_reset_function_locked(struct pci_dev *dev); int pci_try_reset_function(struct pci_dev *dev); int pci_probe_reset_slot(struct pci_slot *slot); int pci_reset_slot(struct pci_slot *slot); -int pci_try_reset_slot(struct pci_slot *slot); int pci_probe_reset_bus(struct pci_bus *bus); int pci_reset_bus(struct pci_bus *bus); -int pci_try_reset_bus(struct pci_bus *bus); +int pci_try_reset_bus(struct pci_dev *dev); void pci_reset_secondary_bus(struct pci_dev *dev); void pcibios_reset_secondary_bus(struct pci_dev *dev); void pci_update_resource(struct pci_dev *dev, int resno);
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2.7.4