[patch 1/3] Add BSS to resource tree

From: Bernhard Walle
Date: Tue Oct 16 2007 - 12:29:39 EST

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This patch adds the BSS to the resource tree just as kernel text and kernel
data are in the resource tree. The main reason behind this is to avoid
crashkernel reservation in that area.

While it's not strictly necessary to have the BSS in the resource tree
(the actual collision detection is done in the reserve_bootmem() function
before), the usage of the BSS resource should be presented to the user
in /proc/iomem just as Kernel data and Kernel code.

Note: The patch currently is only implemented for x86 and ia64 (because
efi_initialize_iomem_resources() has the same signature on i386 and
ia64).

Signed-off-by: Bernhard Walle <bwalle@xxxxxxx>

---
arch/ia64/kernel/efi.c | 10 ++++++----
arch/ia64/kernel/setup.c | 9 ++++++++-
arch/x86/kernel/e820_32.c | 18 +++++++++++++-----
arch/x86/kernel/e820_64.c | 3 ++-
arch/x86/kernel/efi_32.c | 11 +++++++----
arch/x86/kernel/setup_32.c | 4 ++++
arch/x86/kernel/setup_64.c | 9 +++++++++
include/linux/efi.h | 3 +--
8 files changed, 50 insertions(+), 17 deletions(-)

--- a/arch/ia64/kernel/efi.c
+++ b/arch/ia64/kernel/efi.c
@@ -41,6 +41,8 @@

extern efi_status_t efi_call_phys (void *, ...);

+extern struct resource code_resource, data_resource, bss_resource;
+
struct efi efi;
EXPORT_SYMBOL(efi);
static efi_runtime_services_t *runtime;
@@ -1089,8 +1091,7 @@ efi_memmap_init(unsigned long *s, unsign
}

void
-efi_initialize_iomem_resources(struct resource *code_resource,
- struct resource *data_resource)
+efi_initialize_iomem_resources(void)
{
struct resource *res;
void *efi_map_start, *efi_map_end, *p;
@@ -1169,8 +1170,9 @@ efi_initialize_iomem_resources(struct re
* kernel data so we try it repeatedly and
* let the resource manager test it.
*/
- insert_resource(res, code_resource);
- insert_resource(res, data_resource);
+ insert_resource(res, &code_resource);
+ insert_resource(res, &data_resource);
+ insert_resource(res, &bss_resource);
#ifdef CONFIG_KEXEC
insert_resource(res, &efi_memmap_res);
insert_resource(res, &boot_param_res);
--- a/arch/ia64/kernel/setup.c
+++ b/arch/ia64/kernel/setup.c
@@ -90,6 +90,11 @@ static struct resource code_resource = {
.name = "Kernel code",
.flags = IORESOURCE_BUSY | IORESOURCE_MEM
};
+
+static struct resource bss_resource = {
+ .name = "Kernel bss",
+ .flags = IORESOURCE_BUSY | IORESOURCE_MEM
+};
extern char _text[], _end[], _etext[];

unsigned long ia64_max_cacheline_size;
@@ -201,7 +206,9 @@ static int __init register_memory(void)
code_resource.end = ia64_tpa(_etext) - 1;
data_resource.start = ia64_tpa(_etext);
data_resource.end = ia64_tpa(_end) - 1;
- efi_initialize_iomem_resources(&code_resource, &data_resource);
+ bss_resource.start = ia64_tpa(__bss_start);
+ bss_resource.end = ia64_tpa(__bss_stop) - 1;
+ efi_initialize_iomem_resources();

return 0;
}
--- a/arch/x86/kernel/e820_32.c
+++ b/arch/x86/kernel/e820_32.c
@@ -51,6 +51,13 @@ struct resource code_resource = {
.flags = IORESOURCE_BUSY | IORESOURCE_MEM
};

+struct resource bss_resource = {
+ .name = "Kernel bss",
+ .start = 0,
+ .end = 0,
+ .flags = IORESOURCE_BUSY | IORESOURCE_MEM
+};
+
static struct resource system_rom_resource = {
.name = "System ROM",
.start = 0xf0000,
@@ -254,7 +261,7 @@ static void __init probe_roms(void)
* and also for regions reported as reserved by the e820.
*/
static void __init
-legacy_init_iomem_resources(struct resource *code_resource, struct resource *data_resource)
+legacy_init_iomem_resources(void)
{
int i;

@@ -285,8 +292,9 @@ legacy_init_iomem_resources(struct resou
* so we try it repeatedly and let the resource manager
* test it.
*/
- request_resource(res, code_resource);
- request_resource(res, data_resource);
+ request_resource(res, &code_resource);
+ request_resource(res, &data_resource);
+ request_resource(res, &bss_resource);
#ifdef CONFIG_KEXEC
if (crashk_res.start != crashk_res.end)
request_resource(res, &crashk_res);
@@ -307,9 +315,9 @@ static int __init request_standard_resou

printk("Setting up standard PCI resources\n");
if (efi_enabled)
- efi_initialize_iomem_resources(&code_resource, &data_resource);
+ efi_initialize_iomem_resources();
else
- legacy_init_iomem_resources(&code_resource, &data_resource);
+ legacy_init_iomem_resources();

/* EFI systems may still have VGA */
request_resource(&iomem_resource, &video_ram_resource);
--- a/arch/x86/kernel/e820_64.c
+++ b/arch/x86/kernel/e820_64.c
@@ -47,7 +47,7 @@ unsigned long end_pfn_map;
*/
static unsigned long __initdata end_user_pfn = MAXMEM>>PAGE_SHIFT;

-extern struct resource code_resource, data_resource;
+extern struct resource code_resource, data_resource, bss_resource;

/* Check for some hardcoded bad areas that early boot is not allowed to touch */
static inline int bad_addr(unsigned long *addrp, unsigned long size)
@@ -220,6 +220,7 @@ void __init e820_reserve_resources(void)
*/
request_resource(res, &code_resource);
request_resource(res, &data_resource);
+ request_resource(res, &bss_resource);
#ifdef CONFIG_KEXEC
if (crashk_res.start != crashk_res.end)
request_resource(res, &crashk_res);
--- a/arch/x86/kernel/efi_32.c
+++ b/arch/x86/kernel/efi_32.c
@@ -49,6 +49,9 @@ EXPORT_SYMBOL(efi);
static struct efi efi_phys;
struct efi_memory_map memmap;

+extern struct resource iomem_resource;
+extern struct resource code_resource, data_resource, bss_resource;
+
/*
* We require an early boot_ioremap mapping mechanism initially
*/
@@ -599,8 +602,7 @@ void __init efi_enter_virtual_mode(void)
}

void __init
-efi_initialize_iomem_resources(struct resource *code_resource,
- struct resource *data_resource)
+efi_initialize_iomem_resources(void)
{
struct resource *res;
efi_memory_desc_t *md;
@@ -670,8 +672,9 @@ efi_initialize_iomem_resources(struct re
* it repeatedly and let the resource manager test it.
*/
if (md->type == EFI_CONVENTIONAL_MEMORY) {
- request_resource(res, code_resource);
- request_resource(res, data_resource);
+ request_resource(res, &code_resource);
+ request_resource(res, &data_resource);
+ request_resource(res, &bss_resource);
#ifdef CONFIG_KEXEC
request_resource(res, &crashk_res);
#endif
--- a/arch/x86/kernel/setup_32.c
+++ b/arch/x86/kernel/setup_32.c
@@ -60,6 +60,7 @@
#include <asm/vmi.h>
#include <setup_arch.h>
#include <bios_ebda.h>
+#include <asm/cacheflush.h>

/* This value is set up by the early boot code to point to the value
immediately after the boot time page tables. It contains a *physical*
@@ -73,6 +74,7 @@ int disable_pse __devinitdata = 0;
*/
extern struct resource code_resource;
extern struct resource data_resource;
+extern struct resource bss_resource;

/* cpu data as detected by the assembly code in head.S */
struct cpuinfo_x86 new_cpu_data __cpuinitdata = { 0, 0, 0, 0, -1, 1, 0, 0, -1 };
@@ -595,6 +597,8 @@ void __init setup_arch(char **cmdline_p)
code_resource.end = virt_to_phys(_etext)-1;
data_resource.start = virt_to_phys(_etext);
data_resource.end = virt_to_phys(_edata)-1;
+ bss_resource.start = virt_to_phys(&__bss_start);
+ bss_resource.end = virt_to_phys(&__bss_stop)-1;

parse_early_param();

--- a/arch/x86/kernel/setup_64.c
+++ b/arch/x86/kernel/setup_64.c
@@ -59,6 +59,7 @@
#include <asm/numa.h>
#include <asm/sections.h>
#include <asm/dmi.h>
+#include <asm/cacheflush.h>

/*
* Machine setup..
@@ -134,6 +135,12 @@ struct resource code_resource = {
.end = 0,
.flags = IORESOURCE_RAM,
};
+struct resource bss_resource = {
+ .name = "Kernel bss",
+ .start = 0,
+ .end = 0,
+ .flags = IORESOURCE_RAM,
+};

#ifdef CONFIG_PROC_VMCORE
/* elfcorehdr= specifies the location of elf core header
@@ -276,6 +283,8 @@ void __init setup_arch(char **cmdline_p)
code_resource.end = virt_to_phys(&_etext)-1;
data_resource.start = virt_to_phys(&_etext);
data_resource.end = virt_to_phys(&_edata)-1;
+ bss_resource.start = virt_to_phys(&__bss_start);
+ bss_resource.end = virt_to_phys(&__bss_stop)-1;

early_identify_cpu(&boot_cpu_data);

--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -297,8 +297,7 @@ extern u64 efi_mem_attribute (unsigned l
extern int efi_mem_attribute_range (unsigned long phys_addr, unsigned long size,
u64 attr);
extern int __init efi_uart_console_only (void);
-extern void efi_initialize_iomem_resources(struct resource *code_resource,
- struct resource *data_resource);
+extern void efi_initialize_iomem_resources(void);
extern unsigned long efi_get_time(void);
extern int efi_set_rtc_mmss(unsigned long nowtime);
extern int is_available_memory(efi_memory_desc_t * md);

--
-
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