diff options
author | Bjorn Helgaas <bhelgaas@google.com> | 2022-10-06 01:32:53 +0300 |
---|---|---|
committer | Bjorn Helgaas <bhelgaas@google.com> | 2022-10-06 01:32:53 +0300 |
commit | c3acb5661986e2b9bafa2900307d37752c94fb62 (patch) | |
tree | 8110b92519b4a999f62e14f37e64b7f67c2c2118 /drivers/pci | |
parent | 034f93fcb12f579c0108c7e2ca2d17ec4e5170aa (diff) | |
parent | 91fa127794ac1c48069479b9d45eb4c7378c0e30 (diff) |
Merge branch 'pci/rebar'
- Expose a sysfs interface for configuring Resizable BARs so we can resize
BARs before assigning devices to a VM through VFIO (Alex Williamson)
* pci/rebar:
PCI: Expose PCIe Resizable BAR support via sysfs
Diffstat (limited to 'drivers/pci')
-rw-r--r-- | drivers/pci/pci-sysfs.c | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index fc804e08e3cb..0a2eeb82cebd 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -28,6 +28,7 @@ #include <linux/pm_runtime.h> #include <linux/msi.h> #include <linux/of.h> +#include <linux/aperture.h> #include "pci.h" static int sysfs_initialized; /* = 0 */ @@ -1373,6 +1374,112 @@ static const struct attribute_group pci_dev_reset_attr_group = { .is_visible = pci_dev_reset_attr_is_visible, }; +#define pci_dev_resource_resize_attr(n) \ +static ssize_t resource##n##_resize_show(struct device *dev, \ + struct device_attribute *attr, \ + char * buf) \ +{ \ + struct pci_dev *pdev = to_pci_dev(dev); \ + ssize_t ret; \ + \ + pci_config_pm_runtime_get(pdev); \ + \ + ret = sysfs_emit(buf, "%016llx\n", \ + (u64)pci_rebar_get_possible_sizes(pdev, n)); \ + \ + pci_config_pm_runtime_put(pdev); \ + \ + return ret; \ +} \ + \ +static ssize_t resource##n##_resize_store(struct device *dev, \ + struct device_attribute *attr,\ + const char *buf, size_t count)\ +{ \ + struct pci_dev *pdev = to_pci_dev(dev); \ + unsigned long size, flags; \ + int ret, i; \ + u16 cmd; \ + \ + if (kstrtoul(buf, 0, &size) < 0) \ + return -EINVAL; \ + \ + device_lock(dev); \ + if (dev->driver) { \ + ret = -EBUSY; \ + goto unlock; \ + } \ + \ + pci_config_pm_runtime_get(pdev); \ + \ + if ((pdev->class >> 8) == PCI_CLASS_DISPLAY_VGA) { \ + ret = aperture_remove_conflicting_pci_devices(pdev, \ + "resourceN_resize"); \ + if (ret) \ + goto pm_put; \ + } \ + \ + pci_read_config_word(pdev, PCI_COMMAND, &cmd); \ + pci_write_config_word(pdev, PCI_COMMAND, \ + cmd & ~PCI_COMMAND_MEMORY); \ + \ + flags = pci_resource_flags(pdev, n); \ + \ + pci_remove_resource_files(pdev); \ + \ + for (i = 0; i < PCI_STD_NUM_BARS; i++) { \ + if (pci_resource_len(pdev, i) && \ + pci_resource_flags(pdev, i) == flags) \ + pci_release_resource(pdev, i); \ + } \ + \ + ret = pci_resize_resource(pdev, n, size); \ + \ + pci_assign_unassigned_bus_resources(pdev->bus); \ + \ + if (pci_create_resource_files(pdev)) \ + pci_warn(pdev, "Failed to recreate resource files after BAR resizing\n");\ + \ + pci_write_config_word(pdev, PCI_COMMAND, cmd); \ +pm_put: \ + pci_config_pm_runtime_put(pdev); \ +unlock: \ + device_unlock(dev); \ + \ + return ret ? ret : count; \ +} \ +static DEVICE_ATTR_RW(resource##n##_resize) + +pci_dev_resource_resize_attr(0); +pci_dev_resource_resize_attr(1); +pci_dev_resource_resize_attr(2); +pci_dev_resource_resize_attr(3); +pci_dev_resource_resize_attr(4); +pci_dev_resource_resize_attr(5); + +static struct attribute *resource_resize_attrs[] = { + &dev_attr_resource0_resize.attr, + &dev_attr_resource1_resize.attr, + &dev_attr_resource2_resize.attr, + &dev_attr_resource3_resize.attr, + &dev_attr_resource4_resize.attr, + &dev_attr_resource5_resize.attr, + NULL, +}; + +static umode_t resource_resize_is_visible(struct kobject *kobj, + struct attribute *a, int n) +{ + struct pci_dev *pdev = to_pci_dev(kobj_to_dev(kobj)); + + return pci_rebar_get_current_size(pdev, n) < 0 ? 0 : a->mode; +} + +static const struct attribute_group pci_dev_resource_resize_group = { + .attrs = resource_resize_attrs, + .is_visible = resource_resize_is_visible, +}; + int __must_check pci_create_sysfs_dev_files(struct pci_dev *pdev) { if (!sysfs_initialized) @@ -1494,6 +1601,7 @@ const struct attribute_group *pci_dev_groups[] = { #ifdef CONFIG_ACPI &pci_dev_acpi_attr_group, #endif + &pci_dev_resource_resize_group, NULL, }; |