Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull virtio updates from Rusty Russell:
 "OK, this has the big virtio 1.0 implementation, as specified by OASIS.

  On top of tht is the major rework of lguest, to use PCI and virtio
  1.0, to double-check the implementation.

  Then comes the inevitable fixes and cleanups from that work"

* tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (80 commits)
  virtio: don't set VIRTIO_CONFIG_S_DRIVER_OK twice.
  virtio_net: unconditionally define struct virtio_net_hdr_v1.
  tools/lguest: don't use legacy definitions for net device in example launcher.
  virtio: Don't expose legacy net features when VIRTIO_NET_NO_LEGACY defined.
  tools/lguest: use common error macros in the example launcher.
  tools/lguest: give virtqueues names for better error messages
  tools/lguest: more documentation and checking of virtio 1.0 compliance.
  lguest: don't look in console features to find emerg_wr.
  tools/lguest: don't start devices until DRIVER_OK status set.
  tools/lguest: handle indirect partway through chain.
  tools/lguest: insert driver references from the 1.0 spec (4.1 Virtio Over PCI)
  tools/lguest: insert device references from the 1.0 spec (4.1 Virtio Over PCI)
  tools/lguest: rename virtio_pci_cfg_cap field to match spec.
  tools/lguest: fix features_accepted logic in example launcher.
  tools/lguest: handle device reset correctly in example launcher.
  virtual: Documentation: simplify and generalize paravirt_ops.txt
  lguest: remove NOTIFY call and eventfd facility.
  lguest: remove NOTIFY facility from demonstration launcher.
  lguest: use the PCI console device's emerg_wr for early boot messages.
  lguest: always put console in PCI slot #1.
  ...

2 files changed, 53 insertions, 52 deletions

diff --git a/include/linux/lguest_launcher.h b/include/linux/lguest_launcher.h
index 495203ff221c..acd5b12565cc 100644
--- a/include/linux/lguest_launcher.h
+++ b/include/linux/lguest_launcher.h
@@ -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 @@ enum lguest_req
 	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 */
diff --git a/include/linux/virtio_mmio.h b/include/linux/virtio_mmio.h
index 5c7b6f0daef8..c4b09689ab64 100644
--- a/include/linux/virtio_mmio.h
+++ b/include/linux/virtio_mmio.h
@@ -51,23 +51,29 @@
 /* Virtio vendor ID - Read Only */
 #define VIRTIO_MMIO_VENDOR_ID		0x00c
 
-/* Bitmask of the features supported by the host
+/* Bitmask of the features supported by the device (host)
  * (32 bits per set) - Read Only */
-#define VIRTIO_MMIO_HOST_FEATURES	0x010
+#define VIRTIO_MMIO_DEVICE_FEATURES	0x010
 
-/* Host features set selector - Write Only */
-#define VIRTIO_MMIO_HOST_FEATURES_SEL	0x014
+/* Device (host) features set selector - Write Only */
+#define VIRTIO_MMIO_DEVICE_FEATURES_SEL	0x014
 
-/* Bitmask of features activated by the guest
+/* Bitmask of features activated by the driver (guest)
  * (32 bits per set) - Write Only */
-#define VIRTIO_MMIO_GUEST_FEATURES	0x020
+#define VIRTIO_MMIO_DRIVER_FEATURES	0x020
 
 /* Activated features set selector - Write Only */
-#define VIRTIO_MMIO_GUEST_FEATURES_SEL	0x024
+#define VIRTIO_MMIO_DRIVER_FEATURES_SEL	0x024
+
+
+#ifndef VIRTIO_MMIO_NO_LEGACY /* LEGACY DEVICES ONLY! */
 
 /* Guest's memory page size in bytes - Write Only */
 #define VIRTIO_MMIO_GUEST_PAGE_SIZE	0x028
 
+#endif
+
+
 /* Queue selector - Write Only */
 #define VIRTIO_MMIO_QUEUE_SEL		0x030
 
@@ -77,12 +83,21 @@
 /* Queue size for the currently selected queue - Write Only */
 #define VIRTIO_MMIO_QUEUE_NUM		0x038
 
+
+#ifndef VIRTIO_MMIO_NO_LEGACY /* LEGACY DEVICES ONLY! */
+
 /* Used Ring alignment for the currently selected queue - Write Only */
 #define VIRTIO_MMIO_QUEUE_ALIGN		0x03c
 
 /* Guest's PFN for the currently selected queue - Read Write */
 #define VIRTIO_MMIO_QUEUE_PFN		0x040
 
+#endif
+
+
+/* Ready bit for the currently selected queue - Read Write */
+#define VIRTIO_MMIO_QUEUE_READY		0x044
+
 /* Queue notifier - Write Only */
 #define VIRTIO_MMIO_QUEUE_NOTIFY	0x050
 
@@ -95,6 +110,21 @@
 /* Device status register - Read Write */
 #define VIRTIO_MMIO_STATUS		0x070
 
+/* Selected queue's Descriptor Table address, 64 bits in two halves */
+#define VIRTIO_MMIO_QUEUE_DESC_LOW	0x080
+#define VIRTIO_MMIO_QUEUE_DESC_HIGH	0x084
+
+/* Selected queue's Available Ring address, 64 bits in two halves */
+#define VIRTIO_MMIO_QUEUE_AVAIL_LOW	0x090
+#define VIRTIO_MMIO_QUEUE_AVAIL_HIGH	0x094
+
+/* Selected queue's Used Ring address, 64 bits in two halves */
+#define VIRTIO_MMIO_QUEUE_USED_LOW	0x0a0
+#define VIRTIO_MMIO_QUEUE_USED_HIGH	0x0a4
+
+/* Configuration atomicity value */
+#define VIRTIO_MMIO_CONFIG_GENERATION	0x0fc
+
 /* The config space is defined by each driver as
  * the per-driver configuration space - Read Write */
 #define VIRTIO_MMIO_CONFIG		0x100