Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 539a5fe2 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'for-linus' of... 

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86-bigbox-bootparam

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86-bigbox-bootparam:
  x86, boot: Document for linked list of struct setup_data
  x86, boot: export linked list of struct setup_data via debugfs
  x86, boot: add linked list of struct setup_data
  x86, boot: add free_early to early reservation machanism
parents 0124cecf fb884381

Documentation/i386/boot.txt

+26 −0
Original line number Diff line number Diff line
@@ -42,6 +42,8 @@ Protocol 2.05: (Kernel 2.6.20) Make protected mode kernel relocatable. 
Protocol 2.06:	(Kernel 2.6.22) Added a field that contains the size of

		the boot command line



Protocol 2.09:	(kernel 2.6.26) Added a field of 64-bit physical

		pointer to single linked list of struct	setup_data.



**** MEMORY LAYOUT
@@ -172,6 +174,8 @@ Offset Proto Name Meaning 
0240/8	2.07+	hardware_subarch_data Subarchitecture-specific data

0248/4	2.08+	payload_offset	Offset of kernel payload

024C/4	2.08+	payload_length	Length of kernel payload

0250/8	2.09+	setup_data	64-bit physical pointer to linked list

				of struct setup_data



(1) For backwards compatibility, if the setup_sects field contains 0, the

    real value is 4.
@@ -572,6 +576,28 @@ command line is entered using the following protocol: 
	covered by setup_move_size, so you may need to adjust this

	field.



Field name:	setup_data

Type:		write (obligatory)

Offset/size:	0x250/8

Protocol:	2.09+



  The 64-bit physical pointer to NULL terminated single linked list of

  struct setup_data. This is used to define a more extensible boot

  parameters passing mechanism. The definition of struct setup_data is

  as follow:



  struct setup_data {

	  u64 next;

	  u32 type;

	  u32 len;

	  u8  data[0];

  };



  Where, the next is a 64-bit physical pointer to the next node of

  linked list, the next field of the last node is 0; the type is used

  to identify the contents of data; the len is the length of data

  field; the data holds the real payload.





**** MEMORY LAYOUT OF THE REAL-MODE CODE

arch/x86/boot/header.S

+5 −1
Original line number Diff line number Diff line
@@ -120,7 +120,7 @@ _start: 
	# Part 2 of the header, from the old setup.S



		.ascii	"HdrS"		# header signature

		.word	0x0208		# header version number (>= 0x0105)

		.word	0x0209		# header version number (>= 0x0105)

					# or else old loadlin-1.5 will fail)

		.globl realmode_swtch

realmode_swtch:	.word	0, 0		# default_switch, SETUPSEG
@@ -227,6 +227,10 @@ hardware_subarch_data: .quad 0 
payload_offset:		.long input_data

payload_length:		.long input_data_end-input_data



setup_data:		.quad 0			# 64-bit physical pointer to

						# single linked list of

						# struct setup_data



# End of setup header #####################################################



	.section ".inittext", "ax"

arch/x86/kernel/e820_64.c

+22 −0
Original line number Diff line number Diff line
@@ -84,6 +84,28 @@ void __init reserve_early(unsigned long start, unsigned long end, char *name) 
		strncpy(r->name, name, sizeof(r->name) - 1);

}



void __init free_early(unsigned long start, unsigned long end)

{

	struct early_res *r;

	int i, j;



	for (i = 0; i < MAX_EARLY_RES && early_res[i].end; i++) {

		r = &early_res[i];

		if (start == r->start && end == r->end)

			break;

	}

	if (i >= MAX_EARLY_RES || !early_res[i].end)

		panic("free_early on not reserved area: %lx-%lx!", start, end);



	for (j = i + 1; j < MAX_EARLY_RES && early_res[j].end; j++)

		;



	memcpy(&early_res[i], &early_res[i + 1],

	       (j - 1 - i) * sizeof(struct early_res));



	early_res[j - 1].end = 0;

}



void __init early_res_to_bootmem(void)

{

	int i;

arch/x86/kernel/head64.c

+20 −0
Original line number Diff line number Diff line
@@ -11,6 +11,7 @@ 
#include <linux/string.h>

#include <linux/percpu.h>

#include <linux/start_kernel.h>

#include <linux/io.h>



#include <asm/processor.h>

#include <asm/proto.h>
@@ -100,6 +101,24 @@ static void __init reserve_ebda_region(void) 
	reserve_early(lowmem, 0x100000, "BIOS reserved");

}



static void __init reserve_setup_data(void)

{

	struct setup_data *data;

	unsigned long pa_data;

	char buf[32];



	if (boot_params.hdr.version < 0x0209)

		return;

	pa_data = boot_params.hdr.setup_data;

	while (pa_data) {

		data = early_ioremap(pa_data, sizeof(*data));

		sprintf(buf, "setup data %x", data->type);

		reserve_early(pa_data, pa_data+sizeof(*data)+data->len, buf);

		pa_data = data->next;

		early_iounmap(data, sizeof(*data));

	}

}



void __init x86_64_start_kernel(char * real_mode_data)

{

	int i;
@@ -156,6 +175,7 @@ void __init x86_64_start_kernel(char * real_mode_data) 
#endif



	reserve_ebda_region();

	reserve_setup_data();



	/*

	 * At this point everything still needed from the boot loader

arch/x86/kernel/kdebugfs.c

+158 −5
Original line number Diff line number Diff line
@@ -6,14 +6,162 @@ 
 *

 * This file is released under the GPLv2.

 */



#include <linux/debugfs.h>

#include <linux/uaccess.h>

#include <linux/stat.h>

#include <linux/init.h>

#include <linux/io.h>

#include <linux/mm.h>



#include <asm/setup.h>



#ifdef CONFIG_DEBUG_BOOT_PARAMS

struct setup_data_node {

	u64 paddr;

	u32 type;

	u32 len;

};



static ssize_t

setup_data_read(struct file *file, char __user *user_buf, size_t count,

		loff_t *ppos)

{

	struct setup_data_node *node = file->private_data;

	unsigned long remain;

	loff_t pos = *ppos;

	struct page *pg;

	void *p;

	u64 pa;



	if (pos < 0)

		return -EINVAL;

	if (pos >= node->len)

		return 0;



	if (count > node->len - pos)

		count = node->len - pos;

	pa = node->paddr + sizeof(struct setup_data) + pos;

	pg = pfn_to_page((pa + count - 1) >> PAGE_SHIFT);

	if (PageHighMem(pg)) {

		p = ioremap_cache(pa, count);

		if (!p)

			return -ENXIO;

	} else {

		p = __va(pa);

	}



	remain = copy_to_user(user_buf, p, count);



	if (PageHighMem(pg))

		iounmap(p);



	if (remain)

		return -EFAULT;



	*ppos = pos + count;



	return count;

}



static int setup_data_open(struct inode *inode, struct file *file)

{

	file->private_data = inode->i_private;

	return 0;

}



static const struct file_operations fops_setup_data = {

	.read =		setup_data_read,

	.open =		setup_data_open,

};



static int __init

create_setup_data_node(struct dentry *parent, int no,

		       struct setup_data_node *node)

{

	struct dentry *d, *type, *data;

	char buf[16];

	int error;



	sprintf(buf, "%d", no);

	d = debugfs_create_dir(buf, parent);

	if (!d) {

		error = -ENOMEM;

		goto err_return;

	}

	type = debugfs_create_x32("type", S_IRUGO, d, &node->type);

	if (!type) {

		error = -ENOMEM;

		goto err_dir;

	}

	data = debugfs_create_file("data", S_IRUGO, d, node, &fops_setup_data);

	if (!data) {

		error = -ENOMEM;

		goto err_type;

	}

	return 0;



err_type:

	debugfs_remove(type);

err_dir:

	debugfs_remove(d);

err_return:

	return error;

}



static int __init create_setup_data_nodes(struct dentry *parent)

{

	struct setup_data_node *node;

	struct setup_data *data;

	int error, no = 0;

	struct dentry *d;

	struct page *pg;

	u64 pa_data;



	d = debugfs_create_dir("setup_data", parent);

	if (!d) {

		error = -ENOMEM;

		goto err_return;

	}



	pa_data = boot_params.hdr.setup_data;



	while (pa_data) {

		node = kmalloc(sizeof(*node), GFP_KERNEL);

		if (!node) {

			error = -ENOMEM;

			goto err_dir;

		}

		pg = pfn_to_page((pa_data+sizeof(*data)-1) >> PAGE_SHIFT);

		if (PageHighMem(pg)) {

			data = ioremap_cache(pa_data, sizeof(*data));

			if (!data) {

				error = -ENXIO;

				goto err_dir;

			}

		} else {

			data = __va(pa_data);

		}



		node->paddr = pa_data;

		node->type = data->type;

		node->len = data->len;

		error = create_setup_data_node(d, no, node);

		pa_data = data->next;



		if (PageHighMem(pg))

			iounmap(data);

		if (error)

			goto err_dir;

		no++;

	}

	return 0;



err_dir:

	debugfs_remove(d);

err_return:

	return error;

}



static struct debugfs_blob_wrapper boot_params_blob = {

	.data		= &boot_params,

	.size		= sizeof(boot_params),
@@ -21,8 +169,8 @@ static struct debugfs_blob_wrapper boot_params_blob = { 


static int __init boot_params_kdebugfs_init(void)

{

	int error;

	struct dentry *dbp, *version, *data;

	int error;



	dbp = debugfs_create_dir("boot_params", NULL);

	if (!dbp) {
@@ -41,7 +189,13 @@ static int __init boot_params_kdebugfs_init(void) 
		error = -ENOMEM;

		goto err_version;

	}

	error = create_setup_data_nodes(dbp);

	if (error)

		goto err_data;

	return 0;



err_data:

	debugfs_remove(data);

err_version:

	debugfs_remove(version);

err_dir:
@@ -61,5 +215,4 @@ static int __init arch_kdebugfs_init(void) 


	return error;

}



arch_initcall(arch_kdebugfs_init);