Simplify the assignment of memory to virtual machines by requiring a single

command line option "-m <memsize in MB>" to specify the memory size.

Prior to this change the user needed to explicitly specify the amount of
memory allocated below 4G (-m <lowmem>) and the amount above 4G (-M <highmem>).

The "-M" option is no longer supported by 'bhyveload' and 'bhyve'.

The start of the PCI hole is fixed at 3GB and cannot be directly changed
using command line options. However it is still possible to change this in
special circumstances via the 'vm_set_lowmem_limit()' API provided by
libvmmapi.

Submitted by:	Dinakar Medavaram (initial version)
Reviewed by:	grehan
Obtained from:	NetApp

2 files changed, 29 insertions, 60 deletions

diff --git a/usr.sbin/bhyveload/bhyveload.8 b/usr.sbin/bhyveload/bhyveload.8
index 4a05116..97ce791 100644
--- a/usr.sbin/bhyveload/bhyveload.8
+++ b/usr.sbin/bhyveload/bhyveload.8
@@ -35,8 +35,7 @@
 guest inside a bhyve virtual machine
 .Sh SYNOPSIS
 .Nm
-.Op Fl m Ar lowmem
-.Op Fl M Ar highmem
+.Op Fl m Ar mem-size
 .Op Fl d Ar disk-path
 .Op Fl h Ar host-path
 .Ar vmname
@@ -61,22 +60,13 @@ and will be created if it does not already exist.
 .Sh OPTIONS
 The following options are available:
 .Bl -tag -width indent
-.It Fl m Ar lowmem
-.Ar lowmem
-is the amount of memory allocated below 4GB in the guest's physical address
-space.
+.It Fl m Ar mem-size
+.Ar mem-size
+is the amount of memory allocated to the guest in units of megabytes.
 .Pp
 The default value of
-.Ar lowmem
-is 256MB.
-.It Fl M Ar highmem
-.Ar highmem
-is the amount of memory allocated above 4GB in the guest's physical address
-space.
-.Pp
-The default value of
-.Ar highmem
-is 0MB.
+.Ar mem-size
+is 256.
 .It Fl d Ar disk-path
 The
 .Ar disk-path
@@ -93,16 +83,8 @@ that boots off the ISO image
 .Pa /freebsd/release.iso
 and has 1GB memory allocated to it:
 .Pp
-.Dl "bhyveload -m 256 -M 768 -d /freebsd/release.iso freebsd-vm"
+.Dl "bhyveload -m 1024 -d /freebsd/release.iso freebsd-vm"
 .Pp
-In the example above the 1GB allocation is split in two segments:
-.Pp
-.Bl -dash -compact
-.It
-256MB below the 4GB boundary (0MB - 256MB)
-.It
-768MB above the 4GB boundary (4096MB - 4864MB)
-.El
 .Sh SEE ALSO
 .Xr bhyve 4 ,
 .Xr bhyve 8 ,
diff --git a/usr.sbin/bhyveload/bhyveload.c b/usr.sbin/bhyveload/bhyveload.c
index ef12d9f..4cd280c 100644
--- a/usr.sbin/bhyveload/bhyveload.c
+++ b/usr.sbin/bhyveload/bhyveload.c
@@ -88,8 +88,7 @@ static char *host_base = "/";
 static struct termios term, oldterm;
 static int disk_fd = -1;
 
-static char *vmname, *progname, *membase;
-static uint64_t lowmem, highmem;
+static char *vmname, *progname;
 static struct vmctx *ctx;
 
 static uint64_t gdtbase, cr3, rsp;
@@ -323,30 +322,30 @@ cb_diskioctl(void *arg, int unit, u_long cmd, void *data)
 static int
 cb_copyin(void *arg, const void *from, uint64_t to, size_t size)
 {
+	char *ptr;
 
 	to &= 0x7fffffff;
-	if (to > lowmem)
-		return (EFAULT);
-	if (to + size > lowmem)
-		size = lowmem - to;
 
-	memcpy(&membase[to], from, size);
+	ptr = vm_map_gpa(ctx, to, size);
+	if (ptr == NULL)
+		return (EFAULT);
 
+	memcpy(ptr, from, size);
 	return (0);
 }
 
 static int
 cb_copyout(void *arg, uint64_t from, void *to, size_t size)
 {
+	char *ptr;
 
 	from &= 0x7fffffff;
-	if (from > lowmem)
-		return (EFAULT);
-	if (from + size > lowmem)
-		size = lowmem - from;
 
-	memcpy(to, &membase[from], size);
+	ptr = vm_map_gpa(ctx, from, size);
+	if (ptr == NULL)
+		return (EFAULT);
 
+	memcpy(to, ptr, size);
 	return (0);
 }
 
@@ -493,8 +492,8 @@ static void
 cb_getmem(void *arg, uint64_t *ret_lowmem, uint64_t *ret_highmem)
 {
 
-	*ret_lowmem = lowmem;
-	*ret_highmem = highmem;
+	vm_get_memory_seg(ctx, 0, ret_lowmem);
+	vm_get_memory_seg(ctx, 4 * GB, ret_highmem);
 }
 
 static const char *
@@ -551,9 +550,9 @@ static void
 usage(void)
 {
 
-	printf("usage: %s [-d <disk image path>] [-h <host filesystem path>] "
-	       "[-m <lowmem>][-M <highmem>] "
-	       "<vmname>\n", progname);
+	fprintf(stderr,
+		"usage: %s [-m mem-size][-d <disk-path>] [-h <host-path>] "
+		"<vmname>\n", progname);
 	exit(1);
 }
 
@@ -562,16 +561,16 @@ main(int argc, char** argv)
 {
 	void *h;
 	void (*func)(struct loader_callbacks *, void *, int, int);
+	uint64_t mem_size;
 	int opt, error;
 	char *disk_image;
 
 	progname = argv[0];
 
-	lowmem = 128 * MB;
-	highmem = 0;
+	mem_size = 256 * MB;
 	disk_image = NULL;
 
-	while ((opt = getopt(argc, argv, "d:h:m:M:")) != -1) {
+	while ((opt = getopt(argc, argv, "d:h:m:")) != -1) {
 		switch (opt) {
 		case 'd':
 			disk_image = optarg;
@@ -582,13 +581,9 @@ main(int argc, char** argv)
 			break;
 
 		case 'm':
-			lowmem = strtoul(optarg, NULL, 0) * MB;
+			mem_size = strtoul(optarg, NULL, 0) * MB;
 			break;
 		
-		case 'M':
-			highmem = strtoul(optarg, NULL, 0) * MB;
-			break;
-
 		case '?':
 			usage();
 		}
@@ -615,20 +610,12 @@ main(int argc, char** argv)
 		exit(1);
 	}
 
-	error = vm_setup_memory(ctx, 0, lowmem, &membase);
+	error = vm_setup_memory(ctx, mem_size, VM_MMAP_ALL);
 	if (error) {
-		perror("vm_setup_memory(lowmem)");
+		perror("vm_setup_memory");
 		exit(1);
 	}
 
-	if (highmem != 0) {
-		error = vm_setup_memory(ctx, 4 * GB, highmem, NULL);
-		if (error) {
-			perror("vm_setup_memory(highmem)");
-			exit(1);
-		}
-	}
-
 	tcgetattr(0, &term);
 	oldterm = term;
 	term.c_lflag &= ~(ICANON|ECHO);