vfio/pci: Add infrastructure for additional device specific regions
Add support for additional regions with indexes started after the
already defined fixed regions. Device specific code can register
these regions with the new vfio_pci_register_dev_region() function.
The ops structure per region currently only includes read/write
access and a release function, allowing automatic cleanup when the
device is closed. mmap support is only missing here because it's
not needed by the first user queued for this support.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
index 4682207..813a2e6 100644
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -175,7 +175,7 @@
static void vfio_pci_disable(struct vfio_pci_device *vdev)
{
struct pci_dev *pdev = vdev->pdev;
- int bar;
+ int i, bar;
/* Stop the device from further DMA */
pci_clear_master(pdev);
@@ -186,6 +186,13 @@
vdev->virq_disabled = false;
+ for (i = 0; i < vdev->num_regions; i++)
+ vdev->region[i].ops->release(vdev, &vdev->region[i]);
+
+ vdev->num_regions = 0;
+ kfree(vdev->region);
+ vdev->region = NULL; /* don't krealloc a freed pointer */
+
vfio_config_free(vdev);
for (bar = PCI_STD_RESOURCES; bar <= PCI_STD_RESOURCE_END; bar++) {
@@ -463,6 +470,51 @@
return 0;
}
+static int region_type_cap(struct vfio_pci_device *vdev,
+ struct vfio_info_cap *caps,
+ unsigned int type, unsigned int subtype)
+{
+ struct vfio_info_cap_header *header;
+ struct vfio_region_info_cap_type *cap;
+
+ header = vfio_info_cap_add(caps, sizeof(*cap),
+ VFIO_REGION_INFO_CAP_TYPE, 1);
+ if (IS_ERR(header))
+ return PTR_ERR(header);
+
+ cap = container_of(header, struct vfio_region_info_cap_type, header);
+ cap->type = type;
+ cap->subtype = subtype;
+
+ return 0;
+}
+
+int vfio_pci_register_dev_region(struct vfio_pci_device *vdev,
+ unsigned int type, unsigned int subtype,
+ const struct vfio_pci_regops *ops,
+ size_t size, u32 flags, void *data)
+{
+ struct vfio_pci_region *region;
+
+ region = krealloc(vdev->region,
+ (vdev->num_regions + 1) * sizeof(*region),
+ GFP_KERNEL);
+ if (!region)
+ return -ENOMEM;
+
+ vdev->region = region;
+ vdev->region[vdev->num_regions].type = type;
+ vdev->region[vdev->num_regions].subtype = subtype;
+ vdev->region[vdev->num_regions].ops = ops;
+ vdev->region[vdev->num_regions].size = size;
+ vdev->region[vdev->num_regions].flags = flags;
+ vdev->region[vdev->num_regions].data = data;
+
+ vdev->num_regions++;
+
+ return 0;
+}
+
static long vfio_pci_ioctl(void *device_data,
unsigned int cmd, unsigned long arg)
{
@@ -485,7 +537,7 @@
if (vdev->reset_works)
info.flags |= VFIO_DEVICE_FLAGS_RESET;
- info.num_regions = VFIO_PCI_NUM_REGIONS;
+ info.num_regions = VFIO_PCI_NUM_REGIONS + vdev->num_regions;
info.num_irqs = VFIO_PCI_NUM_IRQS;
return copy_to_user((void __user *)arg, &info, minsz);
@@ -494,7 +546,7 @@
struct pci_dev *pdev = vdev->pdev;
struct vfio_region_info info;
struct vfio_info_cap caps = { .buf = NULL, .size = 0 };
- int ret;
+ int i, ret;
minsz = offsetofend(struct vfio_region_info, offset);
@@ -568,7 +620,21 @@
break;
default:
- return -EINVAL;
+ if (info.index >=
+ VFIO_PCI_NUM_REGIONS + vdev->num_regions)
+ return -EINVAL;
+
+ i = info.index - VFIO_PCI_NUM_REGIONS;
+
+ info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
+ info.size = vdev->region[i].size;
+ info.flags = vdev->region[i].flags;
+
+ ret = region_type_cap(vdev, &caps,
+ vdev->region[i].type,
+ vdev->region[i].subtype);
+ if (ret)
+ return ret;
}
if (caps.size) {
@@ -866,7 +932,7 @@
unsigned int index = VFIO_PCI_OFFSET_TO_INDEX(*ppos);
struct vfio_pci_device *vdev = device_data;
- if (index >= VFIO_PCI_NUM_REGIONS)
+ if (index >= VFIO_PCI_NUM_REGIONS + vdev->num_regions)
return -EINVAL;
switch (index) {
@@ -883,6 +949,10 @@
case VFIO_PCI_VGA_REGION_INDEX:
return vfio_pci_vga_rw(vdev, buf, count, ppos, iswrite);
+ default:
+ index -= VFIO_PCI_NUM_REGIONS;
+ return vdev->region[index].ops->rw(vdev, buf,
+ count, ppos, iswrite);
}
return -EINVAL;
@@ -1065,6 +1135,7 @@
return;
vfio_iommu_group_put(pdev->dev.iommu_group, &pdev->dev);
+ kfree(vdev->region);
kfree(vdev);
if (vfio_pci_is_vga(pdev)) {
diff --git a/drivers/vfio/pci/vfio_pci_private.h b/drivers/vfio/pci/vfio_pci_private.h
index 0e7394f..0710bda 100644
--- a/drivers/vfio/pci/vfio_pci_private.h
+++ b/drivers/vfio/pci/vfio_pci_private.h
@@ -14,6 +14,7 @@
#include <linux/mutex.h>
#include <linux/pci.h>
#include <linux/irqbypass.h>
+#include <linux/types.h>
#ifndef VFIO_PCI_PRIVATE_H
#define VFIO_PCI_PRIVATE_H
@@ -33,6 +34,25 @@
struct irq_bypass_producer producer;
};
+struct vfio_pci_device;
+struct vfio_pci_region;
+
+struct vfio_pci_regops {
+ size_t (*rw)(struct vfio_pci_device *vdev, char __user *buf,
+ size_t count, loff_t *ppos, bool iswrite);
+ void (*release)(struct vfio_pci_device *vdev,
+ struct vfio_pci_region *region);
+};
+
+struct vfio_pci_region {
+ u32 type;
+ u32 subtype;
+ const struct vfio_pci_regops *ops;
+ void *data;
+ size_t size;
+ u32 flags;
+};
+
struct vfio_pci_device {
struct pci_dev *pdev;
void __iomem *barmap[PCI_STD_RESOURCE_END + 1];
@@ -45,6 +65,8 @@
struct vfio_pci_irq_ctx *ctx;
int num_ctx;
int irq_type;
+ int num_regions;
+ struct vfio_pci_region *region;
u8 msi_qmax;
u8 msix_bar;
u16 msix_size;
@@ -91,4 +113,9 @@
extern int vfio_config_init(struct vfio_pci_device *vdev);
extern void vfio_config_free(struct vfio_pci_device *vdev);
+
+extern int vfio_pci_register_dev_region(struct vfio_pci_device *vdev,
+ unsigned int type, unsigned int subtype,
+ const struct vfio_pci_regops *ops,
+ size_t size, u32 flags, void *data);
#endif /* VFIO_PCI_PRIVATE_H */