x86, um: ... and asm-x86 move

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

1 files changed, 175 insertions, 0 deletions

diff --git a/arch/x86/include/asm/kexec.h b/arch/x86/include/asm/kexec.h
new file mode 100644
index 00000000000..ea09600d612
--- /dev/null
+++ b/arch/x86/include/asm/kexec.h
@@ -0,0 +1,175 @@
+#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 VA_PGD			3
+# define PA_PTE_0		4
+# define VA_PTE_0		5
+# define PA_PTE_1		6
+# define VA_PTE_1		7
+# define PA_SWAP_PAGE		8
+# ifdef CONFIG_X86_PAE
+#  define PA_PMD_0		9
+#  define VA_PMD_0		10
+#  define PA_PMD_1		11
+#  define VA_PMD_1		12
+#  define PAGES_NR		13
+# else
+#  define PAGES_NR		9
+# endif
+#else
+# define PA_CONTROL_PAGE	0
+# define VA_CONTROL_PAGE	1
+# define PA_PGD			2
+# define VA_PGD			3
+# define PA_PUD_0		4
+# define VA_PUD_0		5
+# define PA_PMD_0		6
+# define VA_PMD_0		7
+# define PA_PTE_0		8
+# define VA_PTE_0		9
+# define PA_PUD_1		10
+# define VA_PUD_1		11
+# define PA_PMD_1		12
+# define VA_PMD_1		13
+# define PA_PTE_1		14
+# define VA_PTE_1		15
+# define PA_TABLE_PAGE		16
+# define PAGES_NR		17
+#endif
+
+#ifdef CONFIG_X86_32
+# define KEXEC_CONTROL_CODE_MAX_SIZE	2048
+#endif
+
+#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
+asmlinkage unsigned long
+relocate_kernel(unsigned long indirection_page,
+		unsigned long control_page,
+		unsigned long start_address,
+		unsigned int has_pae,
+		unsigned int preserve_context);
+#else
+NORET_TYPE void
+relocate_kernel(unsigned long indirection_page,
+		unsigned long page_list,
+		unsigned long start_address) ATTRIB_NORET;
+#endif
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* ASM_X86__KEXEC_H */