--- zzzz-none-000/linux-3.10.107/include/linux/lguest_launcher.h	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/include/linux/lguest_launcher.h	2021-02-04 17:41:59.000000000 +0000
@@ -8,52 +8,13 @@
  *
  * The Guest needs devices to do anything useful.  Since we don't let it touch
  * real devices (think of the damage it could do!) we provide virtual devices.
- * We could emulate a PCI bus with various devices on it, but that is a fairly
- * complex burden for the Host and suboptimal for the Guest, so we have our own
- * simple lguest bus and we use "virtio" drivers.  These drivers need a set of
- * routines from us which will actually do the virtual I/O, but they handle all
- * the net/block/console stuff themselves.  This means that if we want to add
- * a new device, we simply need to write a new virtio driver and create support
- * for it in the Launcher: this code won't need to change.
+ * We emulate a PCI bus with virtio devices on it; we used to have our own
+ * lguest bus which was far simpler, but this tests the virtio 1.0 standard.
  *
  * Virtio devices are also used by kvm, so we can simply reuse their optimized
  * device drivers.  And one day when everyone uses virtio, my plan will be
  * complete.  Bwahahahah!
- *
- * Devices are described by a simplified ID, a status byte, and some "config"
- * bytes which describe this device's configuration.  This is placed by the
- * Launcher just above the top of physical memory:
- */
-struct lguest_device_desc {
-	/* The device type: console, network, disk etc.  Type 0 terminates. */
-	__u8 type;
-	/* The number of virtqueues (first in config array) */
-	__u8 num_vq;
-	/*
-	 * The number of bytes of feature bits.  Multiply by 2: one for host
-	 * features and one for Guest acknowledgements.
-	 */
-	__u8 feature_len;
-	/* The number of bytes of the config array after virtqueues. */
-	__u8 config_len;
-	/* A status byte, written by the Guest. */
-	__u8 status;
-	__u8 config[0];
-};
-
-/*D:135
- * This is how we expect the device configuration field for a virtqueue
- * to be laid out in config space.
  */
-struct lguest_vqconfig {
-	/* The number of entries in the virtio_ring */
-	__u16 num;
-	/* The interrupt we get when something happens. */
-	__u16 irq;
-	/* The page number of the virtio ring for this device. */
-	__u32 pfn;
-};
-/*:*/
 
 /* Write command first word is a request. */
 enum lguest_req
@@ -62,12 +23,22 @@
 	LHREQ_GETDMA, /* No longer used */
 	LHREQ_IRQ, /* + irq */
 	LHREQ_BREAK, /* No longer used */
-	LHREQ_EVENTFD, /* + address, fd. */
+	LHREQ_EVENTFD, /* No longer used. */
+	LHREQ_GETREG, /* + offset within struct pt_regs (then read value). */
+	LHREQ_SETREG, /* + offset within struct pt_regs, value. */
+	LHREQ_TRAP, /* + trap number to deliver to guest. */
 };
 
 /*
- * The alignment to use between consumer and producer parts of vring.
- * x86 pagesize for historical reasons.
+ * This is what read() of the lguest fd populates.  trap ==
+ * LGUEST_TRAP_ENTRY for an LHCALL_NOTIFY (addr is the
+ * argument), 14 for a page fault in the MMIO region (addr is
+ * the trap address, insn is the instruction), or 13 for a GPF
+ * (insn is the instruction).
  */
-#define LGUEST_VRING_ALIGN	4096
+struct lguest_pending {
+	__u8 trap;
+	__u8 insn[7];
+	__u32 addr;
+};
 #endif /* _LINUX_LGUEST_LAUNCHER */