svn commit: r254557 - projects/bhyve_npt_pmap/sys/amd64/vmm

[Neel Natu]

Author: neel
Date: Tue Aug 20 07:48:20 2013
New Revision: 254557
URL: http://svnweb.freebsd.org/changeset/base/254557

Log:
  APIs to manipulate guest physical address space mappings to host MMIO regions.
  
  These APIs will be used for mapping BARs of the pci passthru devices assigned
  to the guest.

Modified:
  projects/bhyve_npt_pmap/sys/amd64/vmm/vmm_mem.c
  projects/bhyve_npt_pmap/sys/amd64/vmm/vmm_mem.h

Modified: projects/bhyve_npt_pmap/sys/amd64/vmm/vmm_mem.c
==============================================================================
--- projects/bhyve_npt_pmap/sys/amd64/vmm/vmm_mem.c	Tue Aug 20 07:40:40 2013	(r254556)
+++ projects/bhyve_npt_pmap/sys/amd64/vmm/vmm_mem.c	Tue Aug 20 07:48:20 2013	(r254557)
@@ -31,12 +31,18 @@ __FBSDID("$FreeBSD$");
 
 #include <sys/param.h>
 #include <sys/systm.h>
+#include <sys/malloc.h>
+#include <sys/sglist.h>
+#include <sys/lock.h>
+#include <sys/rwlock.h>
 
 #include <vm/vm.h>
 #include <vm/vm_param.h>
 #include <vm/pmap.h>
 #include <vm/vm_map.h>
 #include <vm/vm_object.h>
+#include <vm/vm_page.h>
+#include <vm/vm_pager.h>
 
 #include <machine/md_var.h>
 
@@ -50,6 +56,65 @@ vmm_mem_init(void)
 }
 
 vm_object_t
+vmm_mmio_alloc(struct vmspace *vmspace, vm_paddr_t gpa, size_t len,
+	       vm_paddr_t hpa)
+{
+	int error;
+	vm_object_t obj;
+	struct sglist *sg;
+
+	sg = sglist_alloc(1, M_WAITOK);
+	error = sglist_append_phys(sg, hpa, len);
+	KASSERT(error == 0, ("error %d appending physaddr to sglist", error));
+
+	obj = vm_pager_allocate(OBJT_SG, sg, len, VM_PROT_RW, 0, NULL);
+	if (obj != NULL) {
+		/*
+		 * VT-x ignores the MTRR settings when figuring out the
+		 * memory type for translations obtained through EPT.
+		 *
+		 * Therefore we explicitly force the pages provided by
+		 * this object to be mapped as uncacheable.
+		 */
+		VM_OBJECT_WLOCK(obj);
+		error = vm_object_set_memattr(obj, VM_MEMATTR_UNCACHEABLE);
+		VM_OBJECT_WUNLOCK(obj);
+		if (error != KERN_SUCCESS) {
+			panic("vmm_mmio_alloc: vm_object_set_memattr error %d",
+				error);
+		}
+		error = vm_map_find(&vmspace->vm_map, obj, 0, &gpa, len,
+				    VMFS_NO_SPACE, VM_PROT_RW, VM_PROT_RW, 0);
+		if (error != KERN_SUCCESS) {
+			vm_object_deallocate(obj);
+			obj = NULL;
+		}
+	}
+
+	/*
+	 * Drop the reference on the sglist.
+	 *
+	 * If the scatter/gather object was successfully allocated then it
+	 * has incremented the reference count on the sglist. Dropping the
+	 * initial reference count ensures that the sglist will be freed
+	 * when the object is deallocated.
+	 * 
+	 * If the object could not be allocated then we end up freeing the
+	 * sglist.
+	 */
+	sglist_free(sg);
+
+	return (obj);
+}
+
+void
+vmm_mmio_free(struct vmspace *vmspace, vm_paddr_t gpa, size_t len)
+{
+
+	vm_map_remove(&vmspace->vm_map, gpa, gpa + len);
+}
+
+vm_object_t
 vmm_mem_alloc(struct vmspace *vmspace, vm_paddr_t gpa, size_t len)
 {
 	int error;

Modified: projects/bhyve_npt_pmap/sys/amd64/vmm/vmm_mem.h
==============================================================================
--- projects/bhyve_npt_pmap/sys/amd64/vmm/vmm_mem.h	Tue Aug 20 07:40:40 2013	(r254556)
+++ projects/bhyve_npt_pmap/sys/amd64/vmm/vmm_mem.h	Tue Aug 20 07:48:20 2013	(r254557)
@@ -34,7 +34,10 @@ struct vm_object;
 
 int		vmm_mem_init(void);
 struct vm_object *vmm_mem_alloc(struct vmspace *, vm_paddr_t gpa, size_t size);
+struct vm_object *vmm_mmio_alloc(struct vmspace *, vm_paddr_t gpa, size_t len,
+				 vm_paddr_t hpa);
 void		vmm_mem_free(struct vmspace *, vm_paddr_t gpa, size_t size);
+void		vmm_mmio_free(struct vmspace *, vm_paddr_t gpa, size_t size);
 vm_paddr_t	vmm_mem_maxaddr(void);
 
 #endif