Add tftpfs support for the EFI loader

Allow netbooting on efi without having to setup any NFS server by rebuilding the
loader with LOADER_TFTP_SUPPORT like for the i386 pxeloader

Sponsored by:	Gandi.net

sys/boot/common/dev_net.c

@@ -167,8 +167,13 @@ net_open(struct open_file *f, ...)
 		setenv("boot.netif.ip", inet_ntoa(myip), 1);
 		setenv("boot.netif.netmask", intoa(netmask), 1);
 		setenv("boot.netif.gateway", inet_ntoa(gateip), 1);
+#ifdef LOADER_TFTP_SUPPORT
+		setenv("boot.tftproot.server", inet_ntoa(rootip), 1);
+		setenv("boot.tftproot.path", rootpath, 1);
+#else
 		setenv("boot.nfsroot.server", inet_ntoa(rootip), 1);
 		setenv("boot.nfsroot.path", rootpath, 1);
+#endif
 		if (intf_mtu != 0) {
 			char mtu[16];
 			sprintf(mtu, "%u", intf_mtu);

sys/boot/efi/libefi/Makefile

@@ -13,6 +13,10 @@ SRCS+=	time.c
 SRCS+=	time_event.c
 .endif
 
+.if defined(LOADER_TFTP_SUPPORT)
+CFLAGS+=	-DLOADER_TFTP_SUPPORT
+.endif
+
 # We implement a slightly non-standard %S in that it always takes a
 # CHAR16 that's common in UEFI-land instead of a wchar_t. This only
 # seems to matter on arm64 where wchar_t defaults to an int instead

sys/boot/efi/loader/Makefile

@@ -21,6 +21,10 @@ SRCS=	autoload.c \
 	smbios.c \
 	vers.c
 
+.if defined(LOADER_TFTP_SUPPORT)
+CFLAGS+=	-DLOADER_TFTP_SUPPORT
+.endif
+
 .if ${MK_ZFS} != "no"
 SRCS+=		zfs.c
 .PATH:		${.CURDIR}/../../zfs

sys/boot/efi/loader/conf.c

@@ -51,7 +51,11 @@ struct fs_ops *file_system[] = {
 	&dosfs_fsops,
 	&ufs_fsops,
 	&cd9660_fsops,
+#ifdef LOADER_TFTP_SUPPORT
+	&tftp_fsops,
+#else
 	&nfs_fsops,
+#endif
 	&gzipfs_fsops,
 	&bzipfs_fsops,
 	NULL