#define OPREGION_RVDS 0x3c2
#define OPREGION_VERSION 0x16
+struct igd_opregion_vbt {
+ void *opregion;
+ void *vbt_ex;
+};
+
+/**
+ * igd_opregion_shift_copy() - Copy OpRegion to user buffer and shift position.
+ * @dst: User buffer ptr to copy to.
+ * @off: Offset to user buffer ptr. Increased by bytes on return.
+ * @src: Source buffer to copy from.
+ * @pos: Increased by bytes on return.
+ * @remaining: Decreased by bytes on return.
+ * @bytes: Bytes to copy and adjust off, pos and remaining.
+ *
+ * Copy OpRegion to offset from specific source ptr and shift the offset.
+ *
+ * Return: 0 on success, -EFAULT otherwise.
+ *
+ */
+static inline unsigned long igd_opregion_shift_copy(char __user *dst,
+ loff_t *off,
+ void *src,
+ loff_t *pos,
+ size_t *remaining,
+ size_t bytes)
+{
+ if (copy_to_user(dst + (*off), src, bytes))
+ return -EFAULT;
+
+ *off += bytes;
+ *pos += bytes;
+ *remaining -= bytes;
+
+ return 0;
+}
+
static ssize_t vfio_pci_igd_rw(struct vfio_pci_core_device *vdev,
char __user *buf, size_t count, loff_t *ppos,
bool iswrite)
{
unsigned int i = VFIO_PCI_OFFSET_TO_INDEX(*ppos) - VFIO_PCI_NUM_REGIONS;
- void *base = vdev->region[i].data;
- loff_t pos = *ppos & VFIO_PCI_OFFSET_MASK;
+ struct igd_opregion_vbt *opregionvbt = vdev->region[i].data;
+ loff_t pos = *ppos & VFIO_PCI_OFFSET_MASK, off = 0;
+ size_t remaining;
if (pos >= vdev->region[i].size || iswrite)
return -EINVAL;
- count = min(count, (size_t)(vdev->region[i].size - pos));
+ count = min_t(size_t, count, vdev->region[i].size - pos);
+ remaining = count;
+
+ /* Copy until OpRegion version */
+ if (remaining && pos < OPREGION_VERSION) {
+ size_t bytes = min_t(size_t, remaining, OPREGION_VERSION - pos);
+
+ if (igd_opregion_shift_copy(buf, &off,
+ opregionvbt->opregion + pos, &pos,
+ &remaining, bytes))
+ return -EFAULT;
+ }
+
+ /* Copy patched (if necessary) OpRegion version */
+ if (remaining && pos < OPREGION_VERSION + sizeof(__le16)) {
+ size_t bytes = min_t(size_t, remaining,
+ OPREGION_VERSION + sizeof(__le16) - pos);
+ __le16 version = *(__le16 *)(opregionvbt->opregion +
+ OPREGION_VERSION);
+
+ /* Patch to 2.1 if OpRegion 2.0 has extended VBT */
+ if (le16_to_cpu(version) == 0x0200 && opregionvbt->vbt_ex)
+ version = cpu_to_le16(0x0201);
+
+ if (igd_opregion_shift_copy(buf, &off,
+ &version + (pos - OPREGION_VERSION),
+ &pos, &remaining, bytes))
+ return -EFAULT;
+ }
+
+ /* Copy until RVDA */
+ if (remaining && pos < OPREGION_RVDA) {
+ size_t bytes = min_t(size_t, remaining, OPREGION_RVDA - pos);
- if (copy_to_user(buf, base + pos, count))
+ if (igd_opregion_shift_copy(buf, &off,
+ opregionvbt->opregion + pos, &pos,
+ &remaining, bytes))
+ return -EFAULT;
+ }
+
+ /* Copy modified (if necessary) RVDA */
+ if (remaining && pos < OPREGION_RVDA + sizeof(__le64)) {
+ size_t bytes = min_t(size_t, remaining,
+ OPREGION_RVDA + sizeof(__le64) - pos);
+ __le64 rvda = cpu_to_le64(opregionvbt->vbt_ex ?
+ OPREGION_SIZE : 0);
+
+ if (igd_opregion_shift_copy(buf, &off,
+ &rvda + (pos - OPREGION_RVDA),
+ &pos, &remaining, bytes))
+ return -EFAULT;
+ }
+
+ /* Copy the rest of OpRegion */
+ if (remaining && pos < OPREGION_SIZE) {
+ size_t bytes = min_t(size_t, remaining, OPREGION_SIZE - pos);
+
+ if (igd_opregion_shift_copy(buf, &off,
+ opregionvbt->opregion + pos, &pos,
+ &remaining, bytes))
+ return -EFAULT;
+ }
+
+ /* Copy extended VBT if exists */
+ if (remaining &&
+ copy_to_user(buf + off, opregionvbt->vbt_ex + (pos - OPREGION_SIZE),
+ remaining))
return -EFAULT;
*ppos += count;
static void vfio_pci_igd_release(struct vfio_pci_core_device *vdev,
struct vfio_pci_region *region)
{
- memunmap(region->data);
+ struct igd_opregion_vbt *opregionvbt = region->data;
+
+ if (opregionvbt->vbt_ex)
+ memunmap(opregionvbt->vbt_ex);
+
+ memunmap(opregionvbt->opregion);
+ kfree(opregionvbt);
}
static const struct vfio_pci_regops vfio_pci_igd_regops = {
{
__le32 *dwordp = (__le32 *)(vdev->vconfig + OPREGION_PCI_ADDR);
u32 addr, size;
- void *base;
+ struct igd_opregion_vbt *opregionvbt;
int ret;
u16 version;
if (!addr || !(~addr))
return -ENODEV;
- base = memremap(addr, OPREGION_SIZE, MEMREMAP_WB);
- if (!base)
+ opregionvbt = kzalloc(sizeof(*opregionvbt), GFP_KERNEL);
+ if (!opregionvbt)
+ return -ENOMEM;
+
+ opregionvbt->opregion = memremap(addr, OPREGION_SIZE, MEMREMAP_WB);
+ if (!opregionvbt->opregion) {
+ kfree(opregionvbt);
return -ENOMEM;
+ }
- if (memcmp(base, OPREGION_SIGNATURE, 16)) {
- memunmap(base);
+ if (memcmp(opregionvbt->opregion, OPREGION_SIGNATURE, 16)) {
+ memunmap(opregionvbt->opregion);
+ kfree(opregionvbt);
return -EINVAL;
}
- size = le32_to_cpu(*(__le32 *)(base + 16));
+ size = le32_to_cpu(*(__le32 *)(opregionvbt->opregion + 16));
if (!size) {
- memunmap(base);
+ memunmap(opregionvbt->opregion);
+ kfree(opregionvbt);
return -EINVAL;
}
size *= 1024; /* In KB */
/*
- * Support opregion v2.1+
- * When VBT data exceeds 6KB size and cannot be within mailbox #4, then
- * the Extended VBT region next to opregion is used to hold the VBT data.
- * RVDA (Relative Address of VBT Data from Opregion Base) and RVDS
- * (Raw VBT Data Size) from opregion structure member are used to hold the
- * address from region base and size of VBT data. RVDA/RVDS are not
- * defined before opregion 2.0.
- *
- * opregion 2.1+: RVDA is unsigned, relative offset from
- * opregion base, and should point to the end of opregion.
- * otherwise, exposing to userspace to allow read access to everything between
- * the OpRegion and VBT is not safe.
- * RVDS is defined as size in bytes.
+ * OpRegion and VBT:
+ * When VBT data doesn't exceed 6KB, it's stored in Mailbox #4.
+ * When VBT data exceeds 6KB size, Mailbox #4 is no longer large enough
+ * to hold the VBT data, the Extended VBT region is introduced since
+ * OpRegion 2.0 to hold the VBT data. Since OpRegion 2.0, RVDA/RVDS are
+ * introduced to define the extended VBT data location and size.
+ * OpRegion 2.0: RVDA defines the absolute physical address of the
+ * extended VBT data, RVDS defines the VBT data size.
+ * OpRegion 2.1 and above: RVDA defines the relative address of the
+ * extended VBT data to OpRegion base, RVDS defines the VBT data size.
*
- * opregion 2.0: rvda is the physical VBT address.
- * Since rvda is HPA it cannot be directly used in guest.
- * And it should not be practically available for end user,so it is not supported.
+ * Due to the RVDA definition diff in OpRegion VBT (also the only diff
+ * between 2.0 and 2.1), exposing OpRegion and VBT as a contiguous range
+ * for OpRegion 2.0 and above makes it possible to support the
+ * non-contiguous VBT through a single vfio region. From r/w ops view,
+ * only contiguous VBT after OpRegion with version 2.1+ is exposed,
+ * regardless the host OpRegion is 2.0 or non-contiguous 2.1+. The r/w
+ * ops will on-the-fly shift the actural offset into VBT so that data at
+ * correct position can be returned to the requester.
*/
- version = le16_to_cpu(*(__le16 *)(base + OPREGION_VERSION));
+ version = le16_to_cpu(*(__le16 *)(opregionvbt->opregion +
+ OPREGION_VERSION));
if (version >= 0x0200) {
- u64 rvda;
- u32 rvds;
+ u64 rvda = le64_to_cpu(*(__le64 *)(opregionvbt->opregion +
+ OPREGION_RVDA));
+ u32 rvds = le32_to_cpu(*(__le32 *)(opregionvbt->opregion +
+ OPREGION_RVDS));
- rvda = le64_to_cpu(*(__le64 *)(base + OPREGION_RVDA));
- rvds = le32_to_cpu(*(__le32 *)(base + OPREGION_RVDS));
+ /* The extended VBT is valid only when RVDA/RVDS are non-zero */
if (rvda && rvds) {
- /* no support for opregion v2.0 with physical VBT address */
- if (version == 0x0200) {
- memunmap(base);
- pci_err(vdev->pdev,
- "IGD assignment does not support opregion v2.0 with an extended VBT region\n");
- return -EINVAL;
- }
+ size += rvds;
- if (rvda != size) {
- memunmap(base);
- pci_err(vdev->pdev,
- "Extended VBT does not follow opregion on version 0x%04x\n",
- version);
- return -EINVAL;
+ /*
+ * Extended VBT location by RVDA:
+ * Absolute physical addr for 2.0.
+ * Relative addr to OpRegion header for 2.1+.
+ */
+ if (version == 0x0200)
+ addr = rvda;
+ else
+ addr += rvda;
+
+ opregionvbt->vbt_ex = memremap(addr, rvds, MEMREMAP_WB);
+ if (!opregionvbt->vbt_ex) {
+ memunmap(opregionvbt->opregion);
+ kfree(opregionvbt);
+ return -ENOMEM;
}
-
- /* region size for opregion v2.0+: opregion and VBT size. */
- size += rvds;
}
}
- if (size != OPREGION_SIZE) {
- memunmap(base);
- base = memremap(addr, size, MEMREMAP_WB);
- if (!base)
- return -ENOMEM;
- }
-
ret = vfio_pci_register_dev_region(vdev,
PCI_VENDOR_ID_INTEL | VFIO_REGION_TYPE_PCI_VENDOR_TYPE,
- VFIO_REGION_SUBTYPE_INTEL_IGD_OPREGION,
- &vfio_pci_igd_regops, size, VFIO_REGION_INFO_FLAG_READ, base);
+ VFIO_REGION_SUBTYPE_INTEL_IGD_OPREGION, &vfio_pci_igd_regops,
+ size, VFIO_REGION_INFO_FLAG_READ, opregionvbt);
if (ret) {
- memunmap(base);
+ if (opregionvbt->vbt_ex)
+ memunmap(opregionvbt->vbt_ex);
+
+ memunmap(opregionvbt->opregion);
+ kfree(opregionvbt);
return ret;
}
projects / linux.git / commitdiff