[PATCH -mm -v3 1/2] i386/x86_64 boot: setup data
From: Huang, Ying
Date: Wed Sep 19 2007 - 04:56:44 EST
This patch add a field of 64-bit physical pointer to NULL terminated
single linked list of struct setup_data to real-mode kernel
header. This is used as a more extensible boot parameters passing
mechanism.
This patch has been tested against 2.6.23-rc6-mm1 kernel on x86_64. It
is based on the proposal of Peter Anvin.
Known Issues:
1. Where is safe to place the linked list of setup_data?
Because the length of the linked list of setup_data is variable, it
can not be copied into BSS segment of kernel as that of "zero
page". We must find a safe place for it, where it will not be
overwritten by kernel during booting up. The i386 kernel will
overwrite some pages after _end. The x86_64 kernel will overwrite some
pages from 0x1000 on.
ChangeLog:
-- v2 --
- Increase the boot protocol version number.
- Check version number before parsing setup_data.
Signed-off-by: Huang Ying <ying.huang@xxxxxxxxx>
---
arch/i386/Kconfig | 3 ---
arch/i386/boot/header.S | 8 +++++++-
arch/i386/kernel/setup.c | 22 ++++++++++++++++++++++
arch/x86_64/kernel/setup.c | 21 +++++++++++++++++++++
include/asm-i386/bootparam.h | 15 +++++++++++++++
include/asm-i386/io.h | 7 +++++++
6 files changed, 72 insertions(+), 4 deletions(-)
Index: linux-2.6.23-rc6/include/asm-i386/bootparam.h
===================================================================
--- linux-2.6.23-rc6.orig/include/asm-i386/bootparam.h 2007-09-19 10:22:02.000000000 +0800
+++ linux-2.6.23-rc6/include/asm-i386/bootparam.h 2007-09-19 16:41:57.000000000 +0800
@@ -9,6 +9,17 @@
#include <asm/ist.h>
#include <video/edid.h>
+/* setup data types */
+#define SETUP_NONE 0
+
+/* extensible setup data list node */
+struct setup_data {
+ u64 next;
+ u32 type;
+ u32 len;
+ u8 data[0];
+} __attribute__((packed));
+
struct setup_header {
u8 setup_sects;
u16 root_flags;
@@ -41,6 +52,10 @@
u32 initrd_addr_max;
u32 kernel_alignment;
u8 relocatable_kernel;
+ u8 _pad2[3];
+ u32 cmdline_size;
+ u32 _pad3;
+ u64 setup_data;
} __attribute__((packed));
struct sys_desc_table {
Index: linux-2.6.23-rc6/arch/i386/boot/header.S
===================================================================
--- linux-2.6.23-rc6.orig/arch/i386/boot/header.S 2007-09-19 10:22:02.000000000 +0800
+++ linux-2.6.23-rc6/arch/i386/boot/header.S 2007-09-19 10:47:34.000000000 +0800
@@ -119,7 +119,7 @@
# Part 2 of the header, from the old setup.S
.ascii "HdrS" # header signature
- .word 0x0206 # header version number (>= 0x0105)
+ .word 0x0207 # header version number (>= 0x0105)
# or else old loadlin-1.5 will fail)
.globl realmode_swtch
realmode_swtch: .word 0, 0 # default_switch, SETUPSEG
@@ -214,6 +214,12 @@
#added with boot protocol
#version 2.06
+pad4: .long 0
+
+setup_data: .quad 0 # 64-bit physical pointer to
+ # single linked list of
+ # struct setup_data
+
# End of setup header #####################################################
.section ".inittext", "ax"
Index: linux-2.6.23-rc6/arch/x86_64/kernel/setup.c
===================================================================
--- linux-2.6.23-rc6.orig/arch/x86_64/kernel/setup.c 2007-09-19 10:22:02.000000000 +0800
+++ linux-2.6.23-rc6/arch/x86_64/kernel/setup.c 2007-09-19 16:41:57.000000000 +0800
@@ -221,6 +221,25 @@
ebda_size = 64*1024;
}
+void __init parse_setup_data(void)
+{
+ struct setup_data *setup_data;
+ unsigned long pa_setup_data;
+
+ if (boot_params.hdr.version < 0x0207)
+ return;
+ pa_setup_data = boot_params.hdr.setup_data;
+ while (pa_setup_data) {
+ setup_data = early_ioremap(pa_setup_data, PAGE_SIZE);
+ switch (setup_data->type) {
+ default:
+ break;
+ }
+ pa_setup_data = setup_data->next;
+ early_iounmap(setup_data, PAGE_SIZE);
+ }
+}
+
void __init setup_arch(char **cmdline_p)
{
printk(KERN_INFO "Command line: %s\n", boot_command_line);
@@ -256,6 +275,8 @@
strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
*cmdline_p = command_line;
+ parse_setup_data();
+
parse_early_param();
finish_e820_parsing();
Index: linux-2.6.23-rc6/arch/i386/kernel/setup.c
===================================================================
--- linux-2.6.23-rc6.orig/arch/i386/kernel/setup.c 2007-09-19 10:22:02.000000000 +0800
+++ linux-2.6.23-rc6/arch/i386/kernel/setup.c 2007-09-19 10:47:34.000000000 +0800
@@ -496,6 +496,25 @@
return machine_specific_memory_setup();
}
+void __init parse_setup_data(void)
+{
+ struct setup_data *setup_data;
+ unsigned long pa_setup_data, pa_next;
+
+ if (boot_params.hdr.version < 0x0207)
+ return;
+ pa_setup_data = boot_params.hdr.setup_data;
+ while (pa_setup_data) {
+ setup_data = boot_ioremap(pa_setup_data, PAGE_SIZE);
+ pa_next = setup_data->next;
+ switch (setup_data->type) {
+ default:
+ break;
+ }
+ pa_setup_data = pa_next;
+ }
+}
+
/*
* Determine if we were loaded by an EFI loader. If so, then we have also been
* passed the efi memmap, systab, etc., so we should use these data structures
@@ -544,6 +563,9 @@
rd_prompt = ((boot_params.hdr.ram_size & RAMDISK_PROMPT_FLAG) != 0);
rd_doload = ((boot_params.hdr.ram_size & RAMDISK_LOAD_FLAG) != 0);
#endif
+
+ parse_setup_data();
+
ARCH_SETUP
if (efi_enabled)
efi_init();
Index: linux-2.6.23-rc6/include/asm-i386/io.h
===================================================================
--- linux-2.6.23-rc6.orig/include/asm-i386/io.h 2007-09-19 10:22:02.000000000 +0800
+++ linux-2.6.23-rc6/include/asm-i386/io.h 2007-09-19 10:47:34.000000000 +0800
@@ -126,6 +126,13 @@
extern void iounmap(volatile void __iomem *addr);
/*
+ * boot_ioremap is for temporary early boot-time mappings, before
+ * paging_init(), when the boot-time page tables are still in use.
+ * The mapping is currently limited to at most 4 pages.
+ */
+extern void *boot_ioremap(unsigned long offset, unsigned long size);
+
+/*
* bt_ioremap() and bt_iounmap() are for temporary early boot-time
* mappings, before the real ioremap() is functional.
* A boot-time mapping is currently limited to at most 16 pages.
Index: linux-2.6.23-rc6/arch/i386/Kconfig
===================================================================
--- linux-2.6.23-rc6.orig/arch/i386/Kconfig 2007-09-19 10:22:02.000000000 +0800
+++ linux-2.6.23-rc6/arch/i386/Kconfig 2007-09-19 10:47:34.000000000 +0800
@@ -773,11 +773,8 @@
The default yes will allow the kernel to do irq load balancing.
Saying no will keep the kernel from doing irq load balancing.
-# turning this on wastes a bunch of space.
-# Summit needs it only when NUMA is on
config BOOT_IOREMAP
bool
- depends on (((X86_SUMMIT || X86_GENERICARCH) && NUMA) || (X86 && EFI))
default y
config SECCOMP
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/