[PATCH v6 4/6] kexec, x86: put ramdisk/cmd_line above 4G for 64bit bzImage

[Yinghai Lu]

We could put ramdisk/cmdline above for bzImage on 64bit for protocol 2.12.

-v2: change ext_... handling to way that eric like.
-v3: set LOADER_TYPE_KEXEC

Signed-off-by: Yinghai Lu <yinghai at kernel.org>
---
 include/x86/x86-linux.h           |    1 +
 kexec/arch/i386/x86-linux-setup.c |   27 ++++++++++++++++++++++-----
 2 files changed, 23 insertions(+), 5 deletions(-)

diff --git a/include/x86/x86-linux.h b/include/x86/x86-linux.h
index a2452f2..6289f18 100644
--- a/include/x86/x86-linux.h
+++ b/include/x86/x86-linux.h
@@ -146,6 +146,7 @@ struct x86_linux_param_header {
 #define LOADER_TYPE_BOOTSECT_LOADER 2
 #define LOADER_TYPE_SYSLINUX        3
 #define LOADER_TYPE_ETHERBOOT       4
+#define LOADER_TYPE_KEXEC           0x0D
 #define LOADER_TYPE_UNKNOWN         0xFF
 	uint8_t  loader_flags;			/* 0x211 */
 	uint8_t  reserved12[2];			/* 0x212 */
diff --git a/kexec/arch/i386/x86-linux-setup.c b/kexec/arch/i386/x86-linux-setup.c
index b7ab8ea..93b357f 100644
--- a/kexec/arch/i386/x86-linux-setup.c
+++ b/kexec/arch/i386/x86-linux-setup.c
@@ -56,7 +56,7 @@ void setup_linux_bootloader_parameters(
 	unsigned long initrd_base, initrd_addr_max;
 
 	/* Say I'm a boot loader */
-	real_mode->loader_type = LOADER_TYPE_UNKNOWN;
+	real_mode->loader_type = LOADER_TYPE_KEXEC;
 
 	/* No loader flags */
 	real_mode->loader_flags = 0;
@@ -64,7 +64,11 @@ void setup_linux_bootloader_parameters(
 	/* Find the maximum initial ramdisk address */
 	initrd_addr_max = DEFAULT_INITRD_ADDR_MAX;
 	if (real_mode->protocol_version >= 0x0203) {
-		initrd_addr_max = real_mode->initrd_addr_max;
+		if (real_mode->protocol_version >= 0x020c &&
+		    real_mode->xloadflags & (1<<0)) /* CAN_BE_LOADED_ABOVE_4G */
+			initrd_addr_max = ULONG_MAX;
+		else
+			initrd_addr_max = real_mode->initrd_addr_max;
 		dbgprintf("initrd_addr_max is 0x%lx\n", initrd_addr_max);
 	}
 
@@ -81,8 +85,16 @@ void setup_linux_bootloader_parameters(
 	}
 
 	/* Ramdisk address and size */
-	real_mode->initrd_start = initrd_base;
-	real_mode->initrd_size  = initrd_size;
+	real_mode->initrd_start = initrd_base & 0xffffffffUL;
+	real_mode->initrd_size  = initrd_size & 0xffffffffUL;
+
+	if (real_mode->protocol_version >= 0x020c &&
+	    (initrd_base & 0xffffffffUL) != initrd_base)
+		real_mode->ext_ramdisk_image = initrd_base >> 32;
+
+	if (real_mode->protocol_version >= 0x020c &&
+	    (initrd_size & 0xffffffffUL) != initrd_size)
+		real_mode->ext_ramdisk_size = initrd_size >> 32;
 
 	/* The location of the command line */
 	/* if (real_mode_base == 0x90000) { */
@@ -91,7 +103,12 @@ void setup_linux_bootloader_parameters(
 		/* setup_move_size */
 	/* } */
 	if (real_mode->protocol_version >= 0x0202) {
-		real_mode->cmd_line_ptr = real_mode_base + cmdline_offset;
+		unsigned long cmd_line_ptr = real_mode_base + cmdline_offset;
+
+		real_mode->cmd_line_ptr = cmd_line_ptr & 0xffffffffUL;
+		if ((real_mode->protocol_version >= 0x020c) &&
+		    ((cmd_line_ptr & 0xffffffffUL) != cmd_line_ptr))
+			real_mode->ext_cmd_line_ptr = cmd_line_ptr >> 32;
 	}
 
 	/* Fill in the command line */
-- 
1.7.10.4