diff --git a/sys/amd64/amd64/pmap.c b/sys/amd64/amd64/pmap.c
index 3d70532b7fd3..cbd76aa48585 100644
--- a/sys/amd64/amd64/pmap.c
+++ b/sys/amd64/amd64/pmap.c
@@ -3094,8 +3094,8 @@ pmap_growkernel(vm_offset_t addr)
 		return;
 
 	addr = roundup2(addr, NBPDR);
-	if (addr - 1 >= kernel_map->max_offset)
-		addr = kernel_map->max_offset;
+	if (addr - 1 >= vm_map_max(kernel_map))
+		addr = vm_map_max(kernel_map);
 	while (kernel_vm_end < addr) {
 		pdpe = pmap_pdpe(kernel_pmap, kernel_vm_end);
 		if ((*pdpe & X86_PG_V) == 0) {
@@ -3115,8 +3115,8 @@ pmap_growkernel(vm_offset_t addr)
 		pde = pmap_pdpe_to_pde(pdpe, kernel_vm_end);
 		if ((*pde & X86_PG_V) != 0) {
 			kernel_vm_end = (kernel_vm_end + NBPDR) & ~PDRMASK;
-			if (kernel_vm_end - 1 >= kernel_map->max_offset) {
-				kernel_vm_end = kernel_map->max_offset;
+			if (kernel_vm_end - 1 >= vm_map_max(kernel_map)) {
+				kernel_vm_end = vm_map_max(kernel_map);
 				break;                       
 			}
 			continue;
@@ -3134,8 +3134,8 @@ pmap_growkernel(vm_offset_t addr)
 		pde_store(pde, newpdir);
 
 		kernel_vm_end = (kernel_vm_end + NBPDR) & ~PDRMASK;
-		if (kernel_vm_end - 1 >= kernel_map->max_offset) {
-			kernel_vm_end = kernel_map->max_offset;
+		if (kernel_vm_end - 1 >= vm_map_max(kernel_map)) {
+			kernel_vm_end = vm_map_max(kernel_map);
 			break;                       
 		}
 	}
diff --git a/sys/arm/arm/pmap-v6.c b/sys/arm/arm/pmap-v6.c
index 8dd74f15d925..ceedc75cb941 100644
--- a/sys/arm/arm/pmap-v6.c
+++ b/sys/arm/arm/pmap-v6.c
@@ -2043,21 +2043,21 @@ pmap_growkernel(vm_offset_t addr)
 	 *       not called, it could be first unused KVA (which is not
 	 *       rounded up to PTE1_SIZE),
 	 *
-	 *   (2) when all KVA space is mapped and kernel_map->max_offset
+	 *   (2) when all KVA space is mapped and vm_map_max(kernel_map)
 	 *       address is not rounded up to PTE1_SIZE. (For example,
 	 *       it could be 0xFFFFFFFF.)
 	 */
 	kernel_vm_end = pte1_roundup(kernel_vm_end);
 	mtx_assert(&kernel_map->system_mtx, MA_OWNED);
 	addr = roundup2(addr, PTE1_SIZE);
-	if (addr - 1 >= kernel_map->max_offset)
-		addr = kernel_map->max_offset;
+	if (addr - 1 >= vm_map_max(kernel_map))
+		addr = vm_map_max(kernel_map);
 	while (kernel_vm_end < addr) {
 		pte1 = pte1_load(kern_pte1(kernel_vm_end));
 		if (pte1_is_valid(pte1)) {
 			kernel_vm_end += PTE1_SIZE;
-			if (kernel_vm_end - 1 >= kernel_map->max_offset) {
-				kernel_vm_end = kernel_map->max_offset;
+			if (kernel_vm_end - 1 >= vm_map_max(kernel_map)) {
+				kernel_vm_end = vm_map_max(kernel_map);
 				break;
 			}
 			continue;
@@ -2099,8 +2099,8 @@ pmap_growkernel(vm_offset_t addr)
 		pmap_kenter_pte1(kernel_vm_end, PTE1_LINK(pt2_pa));
 
 		kernel_vm_end = kernel_vm_end_new;
-		if (kernel_vm_end - 1 >= kernel_map->max_offset) {
-			kernel_vm_end = kernel_map->max_offset;
+		if (kernel_vm_end - 1 >= vm_map_max(kernel_map)) {
+			kernel_vm_end = vm_map_max(kernel_map);
 			break;
 		}
 	}
diff --git a/sys/arm64/arm64/pmap.c b/sys/arm64/arm64/pmap.c
index 89d6178da5e1..390bfbe307c6 100644
--- a/sys/arm64/arm64/pmap.c
+++ b/sys/arm64/arm64/pmap.c
@@ -1744,8 +1744,8 @@ pmap_growkernel(vm_offset_t addr)
 	mtx_assert(&kernel_map->system_mtx, MA_OWNED);
 
 	addr = roundup2(addr, L2_SIZE);
-	if (addr - 1 >= kernel_map->max_offset)
-		addr = kernel_map->max_offset;
+	if (addr - 1 >= vm_map_max(kernel_map))
+		addr = vm_map_max(kernel_map);
 	while (kernel_vm_end < addr) {
 		l0 = pmap_l0(kernel_pmap, kernel_vm_end);
 		KASSERT(pmap_load(l0) != 0,
@@ -1768,8 +1768,8 @@ pmap_growkernel(vm_offset_t addr)
 		l2 = pmap_l1_to_l2(l1, kernel_vm_end);
 		if ((pmap_load(l2) & ATTR_AF) != 0) {
 			kernel_vm_end = (kernel_vm_end + L2_SIZE) & ~L2_OFFSET;
-			if (kernel_vm_end - 1 >= kernel_map->max_offset) {
-				kernel_vm_end = kernel_map->max_offset;
+			if (kernel_vm_end - 1 >= vm_map_max(kernel_map)) {
+				kernel_vm_end = vm_map_max(kernel_map);
 				break;
 			}
 			continue;
@@ -1787,8 +1787,8 @@ pmap_growkernel(vm_offset_t addr)
 		pmap_invalidate_page(kernel_pmap, kernel_vm_end);
 
 		kernel_vm_end = (kernel_vm_end + L2_SIZE) & ~L2_OFFSET;
-		if (kernel_vm_end - 1 >= kernel_map->max_offset) {
-			kernel_vm_end = kernel_map->max_offset;
+		if (kernel_vm_end - 1 >= vm_map_max(kernel_map)) {
+			kernel_vm_end = vm_map_max(kernel_map);
 			break;
 		}
 	}
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zfs_context.h b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zfs_context.h
index 04606bda48db..a3c0e4c31d0d 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zfs_context.h
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zfs_context.h
@@ -104,13 +104,6 @@ extern "C" {
 #include <vm/vm_object.h>
 #include <vm/vm_kern.h>
 #include <vm/vm_map.h>
-/* There is clash. vm_map.h defines the two below and vdev_cache.c use them. */
-#ifdef min_offset
-#undef min_offset
-#endif
-#ifdef max_offset
-#undef max_offset
-#endif
 #include <vm/vm_extern.h>
 #include <vm/vnode_pager.h>
 
diff --git a/sys/i386/i386/pmap.c b/sys/i386/i386/pmap.c
index 5368c7cc2432..0c1437df5187 100644
--- a/sys/i386/i386/pmap.c
+++ b/sys/i386/i386/pmap.c
@@ -2229,13 +2229,13 @@ pmap_growkernel(vm_offset_t addr)
 
 	mtx_assert(&kernel_map->system_mtx, MA_OWNED);
 	addr = roundup2(addr, NBPDR);
-	if (addr - 1 >= kernel_map->max_offset)
-		addr = kernel_map->max_offset;
+	if (addr - 1 >= vm_map_max(kernel_map))
+		addr = vm_map_max(kernel_map);
 	while (kernel_vm_end < addr) {
 		if (pdir_pde(PTD, kernel_vm_end)) {
 			kernel_vm_end = (kernel_vm_end + NBPDR) & ~PDRMASK;
-			if (kernel_vm_end - 1 >= kernel_map->max_offset) {
-				kernel_vm_end = kernel_map->max_offset;
+			if (kernel_vm_end - 1 >= vm_map_max(kernel_map)) {
+				kernel_vm_end = vm_map_max(kernel_map);
 				break;
 			}
 			continue;
@@ -2257,8 +2257,8 @@ pmap_growkernel(vm_offset_t addr)
 
 		pmap_kenter_pde(kernel_vm_end, newpdir);
 		kernel_vm_end = (kernel_vm_end + NBPDR) & ~PDRMASK;
-		if (kernel_vm_end - 1 >= kernel_map->max_offset) {
-			kernel_vm_end = kernel_map->max_offset;
+		if (kernel_vm_end - 1 >= vm_map_max(kernel_map)) {
+			kernel_vm_end = vm_map_max(kernel_map);
 			break;
 		}
 	}
diff --git a/sys/mips/mips/pmap.c b/sys/mips/mips/pmap.c
index 56afb4a3ca74..a0de635ff396 100644
--- a/sys/mips/mips/pmap.c
+++ b/sys/mips/mips/pmap.c
@@ -1255,8 +1255,8 @@ pmap_growkernel(vm_offset_t addr)
 	mtx_assert(&kernel_map->system_mtx, MA_OWNED);
 	req_class = VM_ALLOC_INTERRUPT;
 	addr = roundup2(addr, NBSEG);
-	if (addr - 1 >= kernel_map->max_offset)
-		addr = kernel_map->max_offset;
+	if (addr - 1 >= vm_map_max(kernel_map))
+		addr = vm_map_max(kernel_map);
 	while (kernel_vm_end < addr) {
 		pdpe = pmap_segmap(kernel_pmap, kernel_vm_end);
 #ifdef __mips_n64
@@ -1272,8 +1272,8 @@ pmap_growkernel(vm_offset_t addr)
 		pde = pmap_pdpe_to_pde(pdpe, kernel_vm_end);
 		if (*pde != 0) {
 			kernel_vm_end = (kernel_vm_end + NBPDR) & ~PDRMASK;
-			if (kernel_vm_end - 1 >= kernel_map->max_offset) {
-				kernel_vm_end = kernel_map->max_offset;
+			if (kernel_vm_end - 1 >= vm_map_max(kernel_map)) {
+				kernel_vm_end = vm_map_max(kernel_map);
 				break;
 			}
 			continue;
@@ -1305,8 +1305,8 @@ pmap_growkernel(vm_offset_t addr)
 			pte[i] = PTE_G;
 
 		kernel_vm_end = (kernel_vm_end + NBPDR) & ~PDRMASK;
-		if (kernel_vm_end - 1 >= kernel_map->max_offset) {
-			kernel_vm_end = kernel_map->max_offset;
+		if (kernel_vm_end - 1 >= vm_map_max(kernel_map)) {
+			kernel_vm_end = vm_map_max(kernel_map);
 			break;
 		}
 	}
diff --git a/sys/riscv/riscv/pmap.c b/sys/riscv/riscv/pmap.c
index 6d5d7cf844d8..8582667b27b9 100644
--- a/sys/riscv/riscv/pmap.c
+++ b/sys/riscv/riscv/pmap.c
@@ -1424,8 +1424,8 @@ pmap_growkernel(vm_offset_t addr)
 	mtx_assert(&kernel_map->system_mtx, MA_OWNED);
 
 	addr = roundup2(addr, L2_SIZE);
-	if (addr - 1 >= kernel_map->max_offset)
-		addr = kernel_map->max_offset;
+	if (addr - 1 >= vm_map_max(kernel_map))
+		addr = vm_map_max(kernel_map);
 	while (kernel_vm_end < addr) {
 		l1 = pmap_l1(kernel_pmap, kernel_vm_end);
 		if (pmap_load(l1) == 0) {
@@ -1452,8 +1452,8 @@ pmap_growkernel(vm_offset_t addr)
 		l2 = pmap_l1_to_l2(l1, kernel_vm_end);
 		if ((pmap_load(l2) & PTE_A) != 0) {
 			kernel_vm_end = (kernel_vm_end + L2_SIZE) & ~L2_OFFSET;
-			if (kernel_vm_end - 1 >= kernel_map->max_offset) {
-				kernel_vm_end = kernel_map->max_offset;
+			if (kernel_vm_end - 1 >= vm_map_max(kernel_map)) {
+				kernel_vm_end = vm_map_max(kernel_map);
 				break;
 			}
 			continue;
@@ -1478,8 +1478,8 @@ pmap_growkernel(vm_offset_t addr)
 		pmap_invalidate_page(kernel_pmap, kernel_vm_end);
 
 		kernel_vm_end = (kernel_vm_end + L2_SIZE) & ~L2_OFFSET;
-		if (kernel_vm_end - 1 >= kernel_map->max_offset) {
-			kernel_vm_end = kernel_map->max_offset;
+		if (kernel_vm_end - 1 >= vm_map_max(kernel_map)) {
+			kernel_vm_end = vm_map_max(kernel_map);
 			break;                       
 		}
 	}
diff --git a/sys/vm/vm_glue.c b/sys/vm/vm_glue.c
index 25db4ad18a4b..7952c81a1afe 100644
--- a/sys/vm/vm_glue.c
+++ b/sys/vm/vm_glue.c
@@ -122,7 +122,7 @@ kernacc(void *addr, int len, int rw)
 	KASSERT((rw & ~VM_PROT_ALL) == 0,
 	    ("illegal ``rw'' argument to kernacc (%x)\n", rw));
 
-	if ((vm_offset_t)addr + len > kernel_map->max_offset ||
+	if ((vm_offset_t)addr + len > vm_map_max(kernel_map) ||
 	    (vm_offset_t)addr + len < (vm_offset_t)addr)
 		return (FALSE);
 
diff --git a/sys/vm/vm_init.c b/sys/vm/vm_init.c
index 19262daf00e3..09e87ed231ed 100644
--- a/sys/vm/vm_init.c
+++ b/sys/vm/vm_init.c
@@ -259,8 +259,8 @@ again:
 	 * Discount the physical memory larger than the size of kernel_map
 	 * to avoid eating up all of KVA space.
 	 */
-	physmem_est = lmin(physmem, btoc(kernel_map->max_offset -
-	    kernel_map->min_offset));
+	physmem_est = lmin(physmem, btoc(vm_map_max(kernel_map) -
+	    vm_map_min(kernel_map)));
 
 	v = kern_vfs_bio_buffer_alloc(v, physmem_est);
 
diff --git a/sys/vm/vm_map.c b/sys/vm/vm_map.c
index c2a7128137a2..9dacd649aaea 100644
--- a/sys/vm/vm_map.c
+++ b/sys/vm/vm_map.c
@@ -339,8 +339,8 @@ vmspace_dofree(struct vmspace *vm)
 	 * Delete all of the mappings and pages they hold, then call
 	 * the pmap module to reclaim anything left.
 	 */
-	(void)vm_map_remove(&vm->vm_map, vm->vm_map.min_offset,
-	    vm->vm_map.max_offset);
+	(void)vm_map_remove(&vm->vm_map, vm_map_min(&vm->vm_map),
+	    vm_map_max(&vm->vm_map));
 
 	pmap_release(vmspace_pmap(vm));
 	vm->vm_map.pmap = NULL;
@@ -799,8 +799,8 @@ _vm_map_init(vm_map_t map, pmap_t pmap, vm_offset_t min, vm_offset_t max)
 	map->needs_wakeup = FALSE;
 	map->system_map = 0;
 	map->pmap = pmap;
-	map->min_offset = min;
-	map->max_offset = max;
+	map->header.end = min;
+	map->header.start = max;
 	map->flags = 0;
 	map->root = NULL;
 	map->timestamp = 0;
@@ -1198,7 +1198,8 @@ vm_map_insert(vm_map_t map, vm_object_t object, vm_ooffset_t offset,
 	/*
 	 * Check that the start and end points are not bogus.
 	 */
-	if (start < map->min_offset || end > map->max_offset || start >= end)
+	if (start < vm_map_min(map) || end > vm_map_max(map) ||
+	    start >= end)
 		return (KERN_INVALID_ADDRESS);
 
 	/*
@@ -1401,9 +1402,8 @@ vm_map_findspace(vm_map_t map, vm_offset_t start, vm_size_t length,
 	 * Request must fit within min/max VM address and must avoid
 	 * address wrap.
 	 */
-	if (start < map->min_offset)
-		start = map->min_offset;
-	if (start + length > map->max_offset || start + length < start)
+	start = MAX(start, vm_map_min(map));
+	if (start + length > vm_map_max(map) || start + length < start)
 		return (1);
 
 	/* Empty tree means wide open address space. */
@@ -3429,7 +3429,7 @@ vmspace_fork(struct vmspace *vm1, vm_ooffset_t *fork_charge)
 
 	old_map = &vm1->vm_map;
 	/* Copy immutable fields of vm1 to vm2. */
-	vm2 = vmspace_alloc(old_map->min_offset, old_map->max_offset, NULL);
+	vm2 = vmspace_alloc(vm_map_min(old_map), vm_map_max(old_map), NULL);
 	if (vm2 == NULL)
 		return (NULL);
 	vm2->vm_taddr = vm1->vm_taddr;
@@ -4329,14 +4329,14 @@ vm_offset_t
 vm_map_max_KBI(const struct vm_map *map)
 {
 
-	return (map->max_offset);
+	return (vm_map_max(map));
 }
 
 vm_offset_t
 vm_map_min_KBI(const struct vm_map *map)
 {
 
-	return (map->min_offset);
+	return (vm_map_min(map));
 }
 
 pmap_t
diff --git a/sys/vm/vm_map.h b/sys/vm/vm_map.h
index 7502b95ee1a8..23548bf7d9b5 100644
--- a/sys/vm/vm_map.h
+++ b/sys/vm/vm_map.h
@@ -173,19 +173,26 @@ vm_map_entry_system_wired_count(vm_map_entry_t entry)
  *	A map is a set of map entries.  These map entries are
  *	organized both as a binary search tree and as a doubly-linked
  *	list.  Both structures are ordered based upon the start and
- *	end addresses contained within each map entry.  The list
- *	header has max start value and min end value to act as
- *	sentinels for sequential search of the doubly-linked list.
+ *	end addresses contained within each map entry.
+ *
+ *	Counterintuitively, the map's min offset value is stored in
+ *	map->header.end, and its max offset value is stored in
+ *	map->header.start.
+ *
+ *	The list header has max start value and min end value to act
+ *	as sentinels for sequential search of the doubly-linked list.
  *	Sleator and Tarjan's top-down splay algorithm is employed to
  *	control height imbalance in the binary search tree.
  *
- * List of locks
+ *	List of locks
  *	(c)	const until freed
  */
 struct vm_map {
 	struct vm_map_entry header;	/* List of entries */
-#define	min_offset	header.end	/* (c) */
-#define	max_offset	header.start	/* (c) */
+/*
+	map min_offset	header.end	(c)
+	map max_offset	header.start	(c)
+*/
 	struct sx lock;			/* Lock for map data */
 	struct mtx system_mtx;
 	int nentries;			/* Number of entries */
@@ -214,13 +221,15 @@ struct vm_map {
 static __inline vm_offset_t
 vm_map_max(const struct vm_map *map)
 {
-	return (map->max_offset);
+
+	return (map->header.start);
 }
 
 static __inline vm_offset_t
 vm_map_min(const struct vm_map *map)
 {
-	return (map->min_offset);
+
+	return (map->header.end);
 }
 
 static __inline pmap_t