linux/arch/x86/include/asm/kexec.h

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#ifndef _ASM_X86_KEXEC_H
#define _ASM_X86_KEXEC_H
#ifdef CONFIG_X86_32
# define PA_CONTROL_PAGE 0
# define VA_CONTROL_PAGE 1
# define PA_PGD 2
# define PA_SWAP_PAGE 3
# define PAGES_NR 4
#else
# define PA_CONTROL_PAGE 0
# define VA_CONTROL_PAGE 1
# define PA_TABLE_PAGE 2
# define PA_SWAP_PAGE 3
# define PAGES_NR 4
#endif
# define KEXEC_CONTROL_CODE_MAX_SIZE 2048
#ifndef __ASSEMBLY__
#include <linux/string.h>
#include <asm/page.h>
#include <asm/ptrace.h>
/*
* KEXEC_SOURCE_MEMORY_LIMIT maximum page get_free_page can return.
* I.e. Maximum page that is mapped directly into kernel memory,
* and kmap is not required.
*
* So far x86_64 is limited to 40 physical address bits.
*/
#ifdef CONFIG_X86_32
/* Maximum physical address we can use pages from */
# define KEXEC_SOURCE_MEMORY_LIMIT (-1UL)
/* Maximum address we can reach in physical address mode */
# define KEXEC_DESTINATION_MEMORY_LIMIT (-1UL)
/* Maximum address we can use for the control code buffer */
# define KEXEC_CONTROL_MEMORY_LIMIT TASK_SIZE
# define KEXEC_CONTROL_PAGE_SIZE 4096
/* The native architecture */
# define KEXEC_ARCH KEXEC_ARCH_386
/* We can also handle crash dumps from 64 bit kernel. */
# define vmcore_elf_check_arch_cross(x) ((x)->e_machine == EM_X86_64)
#else
/* Maximum physical address we can use pages from */
# define KEXEC_SOURCE_MEMORY_LIMIT (0xFFFFFFFFFFUL)
/* Maximum address we can reach in physical address mode */
# define KEXEC_DESTINATION_MEMORY_LIMIT (0xFFFFFFFFFFUL)
/* Maximum address we can use for the control pages */
# define KEXEC_CONTROL_MEMORY_LIMIT (0xFFFFFFFFFFUL)
/* Allocate one page for the pdp and the second for the code */
# define KEXEC_CONTROL_PAGE_SIZE (4096UL + 4096UL)
/* The native architecture */
# define KEXEC_ARCH KEXEC_ARCH_X86_64
#endif
/*
* CPU does not save ss and sp on stack if execution is already
* running in kernel mode at the time of NMI occurrence. This code
* fixes it.
*/
static inline void crash_fixup_ss_esp(struct pt_regs *newregs,
struct pt_regs *oldregs)
{
#ifdef CONFIG_X86_32
newregs->sp = (unsigned long)&(oldregs->sp);
asm volatile("xorl %%eax, %%eax\n\t"
"movw %%ss, %%ax\n\t"
:"=a"(newregs->ss));
#endif
}
/*
* This function is responsible for capturing register states if coming
* via panic otherwise just fix up the ss and sp if coming via kernel
* mode exception.
*/
static inline void crash_setup_regs(struct pt_regs *newregs,
struct pt_regs *oldregs)
{
if (oldregs) {
memcpy(newregs, oldregs, sizeof(*newregs));
crash_fixup_ss_esp(newregs, oldregs);
} else {
#ifdef CONFIG_X86_32
asm volatile("movl %%ebx,%0" : "=m"(newregs->bx));
asm volatile("movl %%ecx,%0" : "=m"(newregs->cx));
asm volatile("movl %%edx,%0" : "=m"(newregs->dx));
asm volatile("movl %%esi,%0" : "=m"(newregs->si));
asm volatile("movl %%edi,%0" : "=m"(newregs->di));
asm volatile("movl %%ebp,%0" : "=m"(newregs->bp));
asm volatile("movl %%eax,%0" : "=m"(newregs->ax));
asm volatile("movl %%esp,%0" : "=m"(newregs->sp));
asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
asm volatile("movl %%ds, %%eax;" :"=a"(newregs->ds));
asm volatile("movl %%es, %%eax;" :"=a"(newregs->es));
asm volatile("pushfl; popl %0" :"=m"(newregs->flags));
#else
asm volatile("movq %%rbx,%0" : "=m"(newregs->bx));
asm volatile("movq %%rcx,%0" : "=m"(newregs->cx));
asm volatile("movq %%rdx,%0" : "=m"(newregs->dx));
asm volatile("movq %%rsi,%0" : "=m"(newregs->si));
asm volatile("movq %%rdi,%0" : "=m"(newregs->di));
asm volatile("movq %%rbp,%0" : "=m"(newregs->bp));
asm volatile("movq %%rax,%0" : "=m"(newregs->ax));
asm volatile("movq %%rsp,%0" : "=m"(newregs->sp));
asm volatile("movq %%r8,%0" : "=m"(newregs->r8));
asm volatile("movq %%r9,%0" : "=m"(newregs->r9));
asm volatile("movq %%r10,%0" : "=m"(newregs->r10));
asm volatile("movq %%r11,%0" : "=m"(newregs->r11));
asm volatile("movq %%r12,%0" : "=m"(newregs->r12));
asm volatile("movq %%r13,%0" : "=m"(newregs->r13));
asm volatile("movq %%r14,%0" : "=m"(newregs->r14));
asm volatile("movq %%r15,%0" : "=m"(newregs->r15));
asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
asm volatile("pushfq; popq %0" :"=m"(newregs->flags));
#endif
newregs->ip = (unsigned long)current_text_addr();
}
}
#ifdef CONFIG_X86_32
kexec jump This patch provides an enhancement to kexec/kdump. It implements the following features: - Backup/restore memory used by the original kernel before/after kexec. - Save/restore CPU state before/after kexec. The features of this patch can be used as a general method to call program in physical mode (paging turning off). This can be used to call BIOS code under Linux. kexec-tools needs to be patched to support kexec jump. The patches and the precompiled kexec can be download from the following URL: source: http://khibernation.sourceforge.net/download/release_v10/kexec-tools/kexec-tools-src_git_kh10.tar.bz2 patches: http://khibernation.sourceforge.net/download/release_v10/kexec-tools/kexec-tools-patches_git_kh10.tar.bz2 binary: http://khibernation.sourceforge.net/download/release_v10/kexec-tools/kexec_git_kh10 Usage example of calling some physical mode code and return: 1. Compile and install patched kernel with following options selected: CONFIG_X86_32=y CONFIG_KEXEC=y CONFIG_PM=y CONFIG_KEXEC_JUMP=y 2. Build patched kexec-tool or download the pre-built one. 3. Build some physical mode executable named such as "phy_mode" 4. Boot kernel compiled in step 1. 5. Load physical mode executable with /sbin/kexec. The shell command line can be as follow: /sbin/kexec --load-preserve-context --args-none phy_mode 6. Call physical mode executable with following shell command line: /sbin/kexec -e Implementation point: To support jumping without reserving memory. One shadow backup page (source page) is allocated for each page used by kexeced code image (destination page). When do kexec_load, the image of kexeced code is loaded into source pages, and before executing, the destination pages and the source pages are swapped, so the contents of destination pages are backupped. Before jumping to the kexeced code image and after jumping back to the original kernel, the destination pages and the source pages are swapped too. C ABI (calling convention) is used as communication protocol between kernel and called code. A flag named KEXEC_PRESERVE_CONTEXT for sys_kexec_load is added to indicate that the loaded kernel image is used for jumping back. Now, only the i386 architecture is supported. Signed-off-by: Huang Ying <ying.huang@intel.com> Acked-by: Vivek Goyal <vgoyal@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Nigel Cunningham <nigel@nigel.suspend2.net> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-26 02:45:07 +00:00
asmlinkage unsigned long
relocate_kernel(unsigned long indirection_page,
unsigned long control_page,
unsigned long start_address,
kexec jump This patch provides an enhancement to kexec/kdump. It implements the following features: - Backup/restore memory used by the original kernel before/after kexec. - Save/restore CPU state before/after kexec. The features of this patch can be used as a general method to call program in physical mode (paging turning off). This can be used to call BIOS code under Linux. kexec-tools needs to be patched to support kexec jump. The patches and the precompiled kexec can be download from the following URL: source: http://khibernation.sourceforge.net/download/release_v10/kexec-tools/kexec-tools-src_git_kh10.tar.bz2 patches: http://khibernation.sourceforge.net/download/release_v10/kexec-tools/kexec-tools-patches_git_kh10.tar.bz2 binary: http://khibernation.sourceforge.net/download/release_v10/kexec-tools/kexec_git_kh10 Usage example of calling some physical mode code and return: 1. Compile and install patched kernel with following options selected: CONFIG_X86_32=y CONFIG_KEXEC=y CONFIG_PM=y CONFIG_KEXEC_JUMP=y 2. Build patched kexec-tool or download the pre-built one. 3. Build some physical mode executable named such as "phy_mode" 4. Boot kernel compiled in step 1. 5. Load physical mode executable with /sbin/kexec. The shell command line can be as follow: /sbin/kexec --load-preserve-context --args-none phy_mode 6. Call physical mode executable with following shell command line: /sbin/kexec -e Implementation point: To support jumping without reserving memory. One shadow backup page (source page) is allocated for each page used by kexeced code image (destination page). When do kexec_load, the image of kexeced code is loaded into source pages, and before executing, the destination pages and the source pages are swapped, so the contents of destination pages are backupped. Before jumping to the kexeced code image and after jumping back to the original kernel, the destination pages and the source pages are swapped too. C ABI (calling convention) is used as communication protocol between kernel and called code. A flag named KEXEC_PRESERVE_CONTEXT for sys_kexec_load is added to indicate that the loaded kernel image is used for jumping back. Now, only the i386 architecture is supported. Signed-off-by: Huang Ying <ying.huang@intel.com> Acked-by: Vivek Goyal <vgoyal@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Nigel Cunningham <nigel@nigel.suspend2.net> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-26 02:45:07 +00:00
unsigned int has_pae,
unsigned int preserve_context);
#else
unsigned long
relocate_kernel(unsigned long indirection_page,
unsigned long page_list,
unsigned long start_address,
unsigned int preserve_context);
#endif
#define ARCH_HAS_KIMAGE_ARCH
#ifdef CONFIG_X86_32
struct kimage_arch {
pgd_t *pgd;
#ifdef CONFIG_X86_PAE
pmd_t *pmd0;
pmd_t *pmd1;
#endif
pte_t *pte0;
pte_t *pte1;
};
#else
struct kimage_arch {
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
};
#endif
#endif /* __ASSEMBLY__ */
#endif /* _ASM_X86_KEXEC_H */