[PATCH v3 06/10] vfio/pci: Add infrastructure for additional device specific regions
From: Alex Williamson
Date: Tue Feb 16 2016 - 16:06:16 EST
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@xxxxxxxxxx>
---
drivers/vfio/pci/vfio_pci.c | 81 +++++++++++++++++++++++++++++++++--
drivers/vfio/pci/vfio_pci_private.h | 27 ++++++++++++
2 files changed, 103 insertions(+), 5 deletions(-)
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 int vfio_pci_enable(struct vfio_pci_device *vdev)
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 @@ static void vfio_pci_disable(struct vfio_pci_device *vdev)
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 @@ static int msix_sparse_mmap_cap(struct vfio_pci_device *vdev,
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 @@ static long vfio_pci_ioctl(void *device_data,
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 @@ static long vfio_pci_ioctl(void *device_data,
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 @@ static long vfio_pci_ioctl(void *device_data,
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 @@ static ssize_t vfio_pci_rw(void *device_data, char __user *buf,
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 @@ static ssize_t vfio_pci_rw(void *device_data, char __user *buf,
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 @@ static void vfio_pci_remove(struct pci_dev *pdev)
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 vfio_pci_irq_ctx {
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_device {
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 void vfio_pci_uninit_perm_bits(void);
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 */