drivers/vfio: Support EEH error injection

The patch adds one more EEH sub-command (VFIO_EEH_PE_INJECT_ERR)
to inject the specified EEH error, which is represented by
(struct vfio_eeh_pe_err), to the indicated PE for testing purpose.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

3 files changed, 35 insertions, 1 deletions

diff --git a/Documentation/vfio.txt b/Documentation/vfio.txt
index 96978eced341..4c746a7e717a 100644
--- a/Documentation/vfio.txt
+++ b/Documentation/vfio.txt
@@ -385,6 +385,18 @@ The code flow from the example above should be slightly changed:
 
         ....
 
+        /* Inject EEH error, which is expected to be caused by 32-bits
+         * config load.
+         */
+        pe_op.op = VFIO_EEH_PE_INJECT_ERR;
+        pe_op.err.type = EEH_ERR_TYPE_32;
+        pe_op.err.func = EEH_ERR_FUNC_LD_CFG_ADDR;
+        pe_op.err.addr = 0ul;
+        pe_op.err.mask = 0ul;
+        ioctl(container, VFIO_EEH_PE_OP, &pe_op);
+
+        ....
+
         /* When 0xFF's returned from reading PCI config space or IO BARs
          * of the PCI device. Check the PE's state to see if that has been
          * frozen.
diff --git a/drivers/vfio/vfio_spapr_eeh.c b/drivers/vfio/vfio_spapr_eeh.c
index 5fa42db769ee..38edeb4729a9 100644
--- a/drivers/vfio/vfio_spapr_eeh.c
+++ b/drivers/vfio/vfio_spapr_eeh.c
@@ -85,6 +85,16 @@ long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group,
                 case VFIO_EEH_PE_CONFIGURE:
                         ret = eeh_pe_configure(pe);
                         break;
+                case VFIO_EEH_PE_INJECT_ERR:
+                        minsz = offsetofend(struct vfio_eeh_pe_op, err.mask);
+                        if (op.argsz < minsz)
+                                return -EINVAL;
+                        if (copy_from_user(&op, (void __user *)arg, minsz))
+                                return -EFAULT;
+
+                        ret = eeh_pe_inject_err(pe, op.err.type, op.err.func,
+                                                op.err.addr, op.err.mask);
+                        break;
                 default:
                         ret = -EINVAL;
                 }
diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
index b57b750c222f..e4fa1995f613 100644
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -470,12 +470,23 @@ struct vfio_iommu_spapr_tce_info {
  * - unfreeze IO/DMA for frozen PE;
  * - read PE state;
  * - reset PE;
- * - configure PE.
+ * - configure PE;
+ * - inject EEH error.
  */
+struct vfio_eeh_pe_err {
+        __u32 type;
+        __u32 func;
+        __u64 addr;
+        __u64 mask;
+};
+
 struct vfio_eeh_pe_op {
         __u32 argsz;
         __u32 flags;
         __u32 op;
+        union {
+                struct vfio_eeh_pe_err err;
+        };
 };
 
 #define VFIO_EEH_PE_DISABLE             0       /* Disable EEH functionality */
@@ -492,6 +503,7 @@ struct vfio_eeh_pe_op {
 #define VFIO_EEH_PE_RESET_HOT           6       /* Assert hot reset          */
 #define VFIO_EEH_PE_RESET_FUNDAMENTAL   7       /* Assert fundamental reset  */
 #define VFIO_EEH_PE_CONFIGURE           8       /* PE configuration          */
+#define VFIO_EEH_PE_INJECT_ERR          9       /* Inject EEH error          */
 
 #define VFIO_EEH_PE_OP                  _IO(VFIO_TYPE, VFIO_BASE + 21)