VM: memtype fix

Memory types in VM are described by methods. Each mapped region has
a type, and all pages instantiated get that type on creation.
Individual page types has to be able to change though. This commit
changes the code to use the memory types of the individual pages,
where appropriate, instead of just the higher-level region, in case
it has changed. This is needed to e.g. support future copy-on-write
MAP_PRIVATE mmap modes.

Change-Id: I5523db14ac036ec774a54392fb67f9acb8725731

servers/vm/mem_shared.c

@@ -52,9 +52,9 @@ static int getsrc(struct vir_region *region,
 {
 	int srcproc;
 
-	if(region->memtype != &mem_type_shared) {
+	if(region->def_memtype != &mem_type_shared) {
 		printf("shared region hasn't shared type but %s.\n",
-			region->memtype->name);
+			region->def_memtype->name);
 		return EINVAL;
 	}
 
@@ -78,9 +78,9 @@ static int getsrc(struct vir_region *region,
                 return EINVAL;
 	}
 
-	if((*r)->memtype != &mem_type_anon) {
+	if((*r)->def_memtype != &mem_type_anon) {
 		printf("source region hasn't anon type but %s.\n",
-			(*r)->memtype->name);
+			(*r)->def_memtype->name);
 		return EINVAL;
 	}
 
@@ -162,7 +162,7 @@ void shared_setsource(struct vir_region *vr, endpoint_t ep,
 	int id = src_vr->id;
 	vir_bytes vaddr = src_vr->vaddr;
 
-	assert(vr->memtype == &mem_type_shared);
+	assert(vr->def_memtype == &mem_type_shared);
 
 	if(!ep || !vaddr || !id) {
 		printf("VM: shared_setsource: zero ep/vaddr/id - ignoring\n");

servers/vm/pb.c

@@ -65,7 +65,7 @@ USE(newphysr,
 	newphysr->ph = newpb;
 	newphysr->parent = parent;
 	newphysr->next_ph_list = newpb->firstregion;
-	newphysr->memtype = parent->memtype;
+	newphysr->memtype = parent->def_memtype;
 	newpb->firstregion = newphysr;);
 	newpb->refcount++;
 }
@@ -120,7 +120,7 @@ void pb_unreferenced(struct vir_region *region, struct phys_region *pr, int rm)
 	if(pb->refcount == 0) {
 		assert(!pb->firstregion);
 		int r;
-		if((r = region->memtype->ev_unreference(pr)) != OK)
+		if((r = region->def_memtype->ev_unreference(pr)) != OK)
 			panic("unref failed, %d", r);
 
 		SLABFREE(pb);

servers/vm/phys_region.h

@@ -13,6 +13,7 @@ typedef struct phys_region {
 	int			written;	/* written to pagetable */
 #endif
 
+	/* what kind of memory is it? */
 	mem_type_t              *memtype;
 
 	/* list of phys_regions that reference the same phys_block */

servers/vm/region.c

@@ -44,9 +44,9 @@ void map_printregion(struct vir_region *vr)
 {
 	int i;
 	struct phys_region *ph;
-	printf("map_printmap: map_name: %s\n", vr->memtype->name);
+	printf("map_printmap: map_name: %s\n", vr->def_memtype->name);
 	printf("\t%lx (len 0x%lx, %lukB), %p\n",
-		vr->vaddr, vr->length, vr->length/1024, vr->memtype->name);
+		vr->vaddr, vr->length, vr->length/1024, vr->def_memtype->name);
 	printf("\t\tphysblocks:\n");
 	for(i = 0; i < vr->length/VM_PAGE_SIZE; i++) {
 		if(!(ph=vr->physblocks[i])) continue;
@@ -122,8 +122,8 @@ static struct vir_region *getnextvr(struct vir_region *vr)
 
 int pr_writable(struct vir_region *vr, struct phys_region *pr)
 {
-	assert(vr->memtype->writable);
-	return ((vr->flags & VR_WRITABLE) && vr->memtype->writable(pr));
+	assert(vr->def_memtype->writable);
+	return ((vr->flags & VR_WRITABLE) && vr->def_memtype->writable(pr));
 }
 
 #if SANITYCHECKS
@@ -434,7 +434,7 @@ USE(newregion,
 	newregion->vaddr = startv;
 	newregion->length = length;
 	newregion->flags = flags;
-	newregion->memtype = memtype;
+	newregion->def_memtype = memtype;
 	newregion->remaps = 0;
 	newregion->id = id++;
 	newregion->lower = newregion->higher = NULL;
@@ -482,8 +482,8 @@ mem_type_t *memtype;
 	}
 
 	/* If a new event is specified, invoke it. */
-	if(newregion->memtype->ev_new) {
-		if(newregion->memtype->ev_new(newregion) != OK) {
+	if(newregion->def_memtype->ev_new) {
+		if(newregion->def_memtype->ev_new(newregion) != OK) {
 			/* ev_new will have freed and removed the region */
 			return NULL;
 		}
@@ -576,8 +576,8 @@ int map_free(struct vir_region *region)
 		return r;
 	}
 
-	if(region->memtype->ev_delete)
-		region->memtype->ev_delete(region);
+	if(region->def_memtype->ev_delete)
+		region->def_memtype->ev_delete(region);
 	free(region->physblocks);
 	region->physblocks = NULL;
 	SLABFREE(region);
@@ -711,13 +711,13 @@ int write;
 	 * writable, nothing to do.
 	 */
 
-	assert(region->memtype->writable);
+	assert(region->def_memtype->writable);
 
-	if(!write || !region->memtype->writable(ph)) {
-		assert(region->memtype->ev_pagefault);
+	if(!write || !region->def_memtype->writable(ph)) {
+		assert(region->def_memtype->ev_pagefault);
 		assert(ph->ph);
 
-		if((r = region->memtype->ev_pagefault(vmp,
+		if((r = region->def_memtype->ev_pagefault(vmp,
 			region, ph, write)) == SUSPEND) {
 			panic("map_pf: memtype->ev_pagefault returned SUSPEND\n");
 			return SUSPEND;
@@ -819,10 +819,10 @@ static struct vir_region *map_copy_region(struct vmproc *vmp, struct vir_region
 #endif
 	vir_bytes p;
 
-	if(!(newvr = region_new(vr->parent, vr->vaddr, vr->length, vr->flags, vr->memtype)))
+	if(!(newvr = region_new(vr->parent, vr->vaddr, vr->length, vr->flags, vr->def_memtype)))
 		return NULL;
 
-	if(vr->memtype->ev_copy && (r=vr->memtype->ev_copy(vr, newvr)) != OK) {
+	if(vr->def_memtype->ev_copy && (r=vr->def_memtype->ev_copy(vr, newvr)) != OK) {
 		map_free(newvr);
 		printf("VM: memtype-specific copy failed (%d)\n", r);
 		return NULL;
@@ -1033,12 +1033,12 @@ int map_region_extend_upto_v(struct vmproc *vmp, vir_bytes v)
 		return ENOMEM;
 	}
 
-	if(!vr->memtype->ev_resize) {
+	if(!vr->def_memtype->ev_resize) {
 		printf("VM: can't resize this type of memory\n");
 		return ENOMEM;
 	}
 
-	return vr->memtype->ev_resize(vmp, vr, offset - vr->vaddr);
+	return vr->def_memtype->ev_resize(vmp, vr, offset - vr->vaddr);
 }
 
 /*========================================================================*
@@ -1129,11 +1129,11 @@ int map_get_phys(struct vmproc *vmp, vir_bytes addr, phys_bytes *r)
 		(vr->vaddr != addr))
 		return EINVAL;
 
-	if (!vr->memtype->regionid)
+	if (!vr->def_memtype->regionid)
 		return EINVAL;
 
 	if(r)
-		*r = vr->memtype->regionid(vr);
+		*r = vr->def_memtype->regionid(vr);
 
 	return OK;
 }
@@ -1146,11 +1146,11 @@ int map_get_ref(struct vmproc *vmp, vir_bytes addr, u8_t *cnt)
 	struct vir_region *vr;
 
 	if (!(vr = map_lookup(vmp, addr, NULL)) ||
-		(vr->vaddr != addr) || !vr->memtype->refcount)
+		(vr->vaddr != addr) || !vr->def_memtype->refcount)
 		return EINVAL;
 
 	if (cnt)
-		*cnt = vr->memtype->refcount(vr);
+		*cnt = vr->def_memtype->refcount(vr);
 
 	return OK;
 }

servers/vm/region.h

@@ -25,13 +25,11 @@ struct phys_block {
 	u32_t			seencount;
 #endif
 	phys_bytes		phys;	/* physical memory */
-	u8_t			refcount;	/* Refcount of these pages */
-
-	/* what kind of memory is it? */
-	mem_type_t		*memtype;
 
 	/* first in list of phys_regions that reference this block */
 	struct phys_region	*firstregion;	
+	u8_t			refcount;	/* Refcount of these pages */
+	u8_t			flags;
 };
 
 typedef struct vir_region {
@@ -40,7 +38,7 @@ typedef struct vir_region {
 	struct phys_region	**physblocks;
 	u16_t		flags;
 	struct vmproc *parent;	/* Process that owns this vir_region. */
-	mem_type_t	*memtype; /* Default instantiated memory type. */
+	mem_type_t	*def_memtype; /* Default instantiated memory type. */
 	int		remaps;
 	u32_t		id;     /* unique id */