tools/virtio: add dma stubs

Fixes build after recent IOMMU-related changes,
mustly by adding more stubs.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
diff --git a/tools/virtio/linux/dma-mapping.h b/tools/virtio/linux/dma-mapping.h
index 4f93af8..18601f6 100644
--- a/tools/virtio/linux/dma-mapping.h
+++ b/tools/virtio/linux/dma-mapping.h
@@ -14,4 +14,20 @@
 	DMA_NONE = 3,
 };
 
+#define dma_alloc_coherent(d, s, hp, f) ({ \
+	void *__dma_alloc_coherent_p = kmalloc((s), (f)); \
+	*(hp) = (unsigned long)__dma_alloc_coherent_p; \
+	__dma_alloc_coherent_p; \
+})
+
+#define dma_free_coherent(d, s, p, h) kfree(p)
+
+#define dma_map_page(d, p, o, s, dir) (page_to_phys(p) + (o))
+
+#define dma_map_single(d, p, s, dir) (virt_to_phys(p))
+#define dma_mapping_error(...) (0)
+
+#define dma_unmap_single(...) do { } while (0)
+#define dma_unmap_page(...) do { } while (0)
+
 #endif
diff --git a/tools/virtio/linux/kernel.h b/tools/virtio/linux/kernel.h
index 0338499..d9554fc 100644
--- a/tools/virtio/linux/kernel.h
+++ b/tools/virtio/linux/kernel.h
@@ -20,7 +20,9 @@
 
 #define PAGE_SIZE getpagesize()
 #define PAGE_MASK (~(PAGE_SIZE-1))
+#define PAGE_ALIGN(x) ((x + PAGE_SIZE - 1) & PAGE_MASK)
 
+typedef unsigned long long phys_addr_t;
 typedef unsigned long long dma_addr_t;
 typedef size_t __kernel_size_t;
 typedef unsigned int __wsum;
@@ -57,6 +59,11 @@
 	return p;
 }
 
+static inline void *alloc_pages_exact(size_t s, gfp_t gfp)
+{
+	return kmalloc(s, gfp);
+}
+
 static inline void kfree(void *p)
 {
 	if (p >= __kfree_ignore_start && p < __kfree_ignore_end)
@@ -64,6 +71,11 @@
 	free(p);
 }
 
+static inline void free_pages_exact(void *p, size_t s)
+{
+	kfree(p);
+}
+
 static inline void *krealloc(void *p, size_t s, gfp_t gfp)
 {
 	return realloc(p, s);
@@ -105,6 +117,8 @@
 #define dev_err(dev, format, ...) fprintf (stderr, format, ## __VA_ARGS__)
 #define dev_warn(dev, format, ...) fprintf (stderr, format, ## __VA_ARGS__)
 
+#define WARN_ON_ONCE(cond) ((cond) && fprintf (stderr, "WARNING\n"))
+
 #define min(x, y) ({				\
 	typeof(x) _min1 = (x);			\
 	typeof(y) _min2 = (y);			\
diff --git a/tools/virtio/linux/slab.h b/tools/virtio/linux/slab.h
index 81baeac..7e1c119 100644
--- a/tools/virtio/linux/slab.h
+++ b/tools/virtio/linux/slab.h
@@ -1,2 +1,6 @@
 #ifndef LINUX_SLAB_H
+#define GFP_KERNEL 0
+#define GFP_ATOMIC 0
+#define __GFP_NOWARN 0
+#define __GFP_ZERO 0
 #endif
diff --git a/tools/virtio/linux/virtio.h b/tools/virtio/linux/virtio.h
index ee125e7..9377c8b 100644
--- a/tools/virtio/linux/virtio.h
+++ b/tools/virtio/linux/virtio.h
@@ -3,8 +3,12 @@
 #include <linux/scatterlist.h>
 #include <linux/kernel.h>
 
+struct device {
+	void *parent;
+};
+
 struct virtio_device {
-	void *dev;
+	struct device dev;
 	u64 features;
 };
 
diff --git a/tools/virtio/linux/virtio_config.h b/tools/virtio/linux/virtio_config.h
index 57a6964..9ba1181 100644
--- a/tools/virtio/linux/virtio_config.h
+++ b/tools/virtio/linux/virtio_config.h
@@ -40,6 +40,19 @@
 #define virtio_has_feature(dev, feature) \
 	(__virtio_test_bit((dev), feature))
 
+/**
+ * virtio_has_iommu_quirk - determine whether this device has the iommu quirk
+ * @vdev: the device
+ */
+static inline bool virtio_has_iommu_quirk(const struct virtio_device *vdev)
+{
+	/*
+	 * Note the reverse polarity of the quirk feature (compared to most
+	 * other features), this is for compatibility with legacy systems.
+	 */
+	return !virtio_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM);
+}
+
 static inline bool virtio_is_little_endian(struct virtio_device *vdev)
 {
 	return virtio_has_feature(vdev, VIRTIO_F_VERSION_1) ||