1 files changed, 69 insertions, 1 deletions

diff --git a/drivers/vfio/pci/vfio_pci_config.c b/drivers/vfio/pci/vfio_pci_config.c
index ff75ca31a199..a8657ef6382f 100644
--- a/drivers/vfio/pci/vfio_pci_config.c
+++ b/drivers/vfio/pci/vfio_pci_config.c
@@ -671,6 +671,73 @@ static int __init init_pci_cap_pm_perm(struct perm_bits *perm)
 	return 0;
 }
 
+static int vfio_vpd_config_write(struct vfio_pci_device *vdev, int pos,
+				 int count, struct perm_bits *perm,
+				 int offset, __le32 val)
+{
+	struct pci_dev *pdev = vdev->pdev;
+	__le16 *paddr = (__le16 *)(vdev->vconfig + pos - offset + PCI_VPD_ADDR);
+	__le32 *pdata = (__le32 *)(vdev->vconfig + pos - offset + PCI_VPD_DATA);
+	u16 addr;
+	u32 data;
+
+	/*
+	 * Write through to emulation.  If the write includes the upper byte
+	 * of PCI_VPD_ADDR, then the PCI_VPD_ADDR_F bit is written and we
+	 * have work to do.
+	 */
+	count = vfio_default_config_write(vdev, pos, count, perm, offset, val);
+	if (count < 0 || offset > PCI_VPD_ADDR + 1 ||
+	    offset + count <= PCI_VPD_ADDR + 1)
+		return count;
+
+	addr = le16_to_cpu(*paddr);
+
+	if (addr & PCI_VPD_ADDR_F) {
+		data = le32_to_cpu(*pdata);
+		if (pci_write_vpd(pdev, addr & ~PCI_VPD_ADDR_F, 4, &data) != 4)
+			return count;
+	} else {
+		if (pci_read_vpd(pdev, addr, 4, &data) != 4)
+			return count;
+		*pdata = cpu_to_le32(data);
+	}
+
+	/*
+	 * Toggle PCI_VPD_ADDR_F in the emulated PCI_VPD_ADDR register to
+	 * signal completion.  If an error occurs above, we assume that not
+	 * toggling this bit will induce a driver timeout.
+	 */
+	addr ^= PCI_VPD_ADDR_F;
+	*paddr = cpu_to_le16(addr);
+
+	return count;
+}
+
+/* Permissions for Vital Product Data capability */
+static int __init init_pci_cap_vpd_perm(struct perm_bits *perm)
+{
+	if (alloc_perm_bits(perm, pci_cap_length[PCI_CAP_ID_VPD]))
+		return -ENOMEM;
+
+	perm->writefn = vfio_vpd_config_write;
+
+	/*
+	 * We always virtualize the next field so we can remove
+	 * capabilities from the chain if we want to.
+	 */
+	p_setb(perm, PCI_CAP_LIST_NEXT, (u8)ALL_VIRT, NO_WRITE);
+
+	/*
+	 * Both the address and data registers are virtualized to
+	 * enable access through the pci_vpd_read/write functions
+	 */
+	p_setw(perm, PCI_VPD_ADDR, (u16)ALL_VIRT, (u16)ALL_WRITE);
+	p_setd(perm, PCI_VPD_DATA, ALL_VIRT, ALL_WRITE);
+
+	return 0;
+}
+
 /* Permissions for PCI-X capability */
 static int __init init_pci_cap_pcix_perm(struct perm_bits *perm)
 {
@@ -790,6 +857,7 @@ void vfio_pci_uninit_perm_bits(void)
 	free_perm_bits(&cap_perms[PCI_CAP_ID_BASIC]);
 
 	free_perm_bits(&cap_perms[PCI_CAP_ID_PM]);
+	free_perm_bits(&cap_perms[PCI_CAP_ID_VPD]);
 	free_perm_bits(&cap_perms[PCI_CAP_ID_PCIX]);
 	free_perm_bits(&cap_perms[PCI_CAP_ID_EXP]);
 	free_perm_bits(&cap_perms[PCI_CAP_ID_AF]);
@@ -807,7 +875,7 @@ int __init vfio_pci_init_perm_bits(void)
 
 	/* Capabilities */
 	ret |= init_pci_cap_pm_perm(&cap_perms[PCI_CAP_ID_PM]);
-	cap_perms[PCI_CAP_ID_VPD].writefn = vfio_raw_config_write;
+	ret |= init_pci_cap_vpd_perm(&cap_perms[PCI_CAP_ID_VPD]);
 	ret |= init_pci_cap_pcix_perm(&cap_perms[PCI_CAP_ID_PCIX]);
 	cap_perms[PCI_CAP_ID_VNDR].writefn = vfio_raw_config_write;
 	ret |= init_pci_cap_exp_perm(&cap_perms[PCI_CAP_ID_EXP]);