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[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [Xen-changelog] Add arch/i386/kernel/{asm-offsets.c, sysenter.c, vm86.c, vsyscall.S} to sparse tree.
# HG changeset patch
# User cl349@xxxxxxxxxxxxxxxxxxxx
# Node ID f97dd89691e7b1f737410a70d229f252883b6b95
# Parent 3083585fb248f1db56460eeb296012b67f5b6a07
Add arch/i386/kernel/{asm-offsets.c,sysenter.c,vm86.c,vsyscall.S} to sparse
tree.
Signed-off-by: Christian Limpach <Christian.Limpach@xxxxxxxxxxxx>
diff -r 3083585fb248 -r f97dd89691e7
linux-2.6-xen-sparse/arch/i386/kernel/asm-offsets.c
--- /dev/null Mon Feb 20 14:08:39 2006
+++ b/linux-2.6-xen-sparse/arch/i386/kernel/asm-offsets.c Mon Feb 20
14:37:13 2006
@@ -0,0 +1,72 @@
+/*
+ * Generate definitions needed by assembly language modules.
+ * This code generates raw asm output which is post-processed
+ * to extract and format the required data.
+ */
+
+#include <linux/sched.h>
+#include <linux/signal.h>
+#include <linux/personality.h>
+#include <linux/suspend.h>
+#include <asm/ucontext.h>
+#include "sigframe.h"
+#include <asm/fixmap.h>
+#include <asm/processor.h>
+#include <asm/thread_info.h>
+
+#define DEFINE(sym, val) \
+ asm volatile("\n->" #sym " %0 " #val : : "i" (val))
+
+#define BLANK() asm volatile("\n->" : : )
+
+#define OFFSET(sym, str, mem) \
+ DEFINE(sym, offsetof(struct str, mem));
+
+void foo(void)
+{
+ OFFSET(SIGCONTEXT_eax, sigcontext, eax);
+ OFFSET(SIGCONTEXT_ebx, sigcontext, ebx);
+ OFFSET(SIGCONTEXT_ecx, sigcontext, ecx);
+ OFFSET(SIGCONTEXT_edx, sigcontext, edx);
+ OFFSET(SIGCONTEXT_esi, sigcontext, esi);
+ OFFSET(SIGCONTEXT_edi, sigcontext, edi);
+ OFFSET(SIGCONTEXT_ebp, sigcontext, ebp);
+ OFFSET(SIGCONTEXT_esp, sigcontext, esp);
+ OFFSET(SIGCONTEXT_eip, sigcontext, eip);
+ BLANK();
+
+ OFFSET(CPUINFO_x86, cpuinfo_x86, x86);
+ OFFSET(CPUINFO_x86_vendor, cpuinfo_x86, x86_vendor);
+ OFFSET(CPUINFO_x86_model, cpuinfo_x86, x86_model);
+ OFFSET(CPUINFO_x86_mask, cpuinfo_x86, x86_mask);
+ OFFSET(CPUINFO_hard_math, cpuinfo_x86, hard_math);
+ OFFSET(CPUINFO_cpuid_level, cpuinfo_x86, cpuid_level);
+ OFFSET(CPUINFO_x86_capability, cpuinfo_x86, x86_capability);
+ OFFSET(CPUINFO_x86_vendor_id, cpuinfo_x86, x86_vendor_id);
+ BLANK();
+
+ OFFSET(TI_task, thread_info, task);
+ OFFSET(TI_exec_domain, thread_info, exec_domain);
+ OFFSET(TI_flags, thread_info, flags);
+ OFFSET(TI_status, thread_info, status);
+ OFFSET(TI_cpu, thread_info, cpu);
+ OFFSET(TI_preempt_count, thread_info, preempt_count);
+ OFFSET(TI_addr_limit, thread_info, addr_limit);
+ OFFSET(TI_restart_block, thread_info, restart_block);
+ BLANK();
+
+ OFFSET(EXEC_DOMAIN_handler, exec_domain, handler);
+ OFFSET(RT_SIGFRAME_sigcontext, rt_sigframe, uc.uc_mcontext);
+ BLANK();
+
+ OFFSET(pbe_address, pbe, address);
+ OFFSET(pbe_orig_address, pbe, orig_address);
+ OFFSET(pbe_next, pbe, next);
+
+ /* Offset from the sysenter stack to tss.esp0 */
+ DEFINE(TSS_sysenter_esp0, offsetof(struct tss_struct, esp0) -
+ sizeof(struct tss_struct));
+
+ DEFINE(PAGE_SIZE_asm, PAGE_SIZE);
+ DEFINE(VSYSCALL_BASE, __fix_to_virt(FIX_VSYSCALL));
+}
diff -r 3083585fb248 -r f97dd89691e7
linux-2.6-xen-sparse/arch/i386/kernel/sysenter.c
--- /dev/null Mon Feb 20 14:08:39 2006
+++ b/linux-2.6-xen-sparse/arch/i386/kernel/sysenter.c Mon Feb 20 14:37:13 2006
@@ -0,0 +1,67 @@
+/*
+ * linux/arch/i386/kernel/sysenter.c
+ *
+ * (C) Copyright 2002 Linus Torvalds
+ *
+ * This file contains the needed initializations to support sysenter.
+ */
+
+#include <linux/init.h>
+#include <linux/smp.h>
+#include <linux/thread_info.h>
+#include <linux/sched.h>
+#include <linux/gfp.h>
+#include <linux/string.h>
+#include <linux/elf.h>
+
+#include <asm/cpufeature.h>
+#include <asm/msr.h>
+#include <asm/pgtable.h>
+#include <asm/unistd.h>
+
+extern asmlinkage void sysenter_entry(void);
+
+void enable_sep_cpu(void)
+{
+ int cpu = get_cpu();
+ struct tss_struct *tss = &per_cpu(init_tss, cpu);
+
+ if (!boot_cpu_has(X86_FEATURE_SEP)) {
+ put_cpu();
+ return;
+ }
+
+ tss->ss1 = __KERNEL_CS;
+ tss->esp1 = sizeof(struct tss_struct) + (unsigned long) tss;
+ wrmsr(MSR_IA32_SYSENTER_CS, __KERNEL_CS, 0);
+ wrmsr(MSR_IA32_SYSENTER_ESP, tss->esp1, 0);
+ wrmsr(MSR_IA32_SYSENTER_EIP, (unsigned long) sysenter_entry, 0);
+ put_cpu();
+}
+
+/*
+ * These symbols are defined by vsyscall.o to mark the bounds
+ * of the ELF DSO images included therein.
+ */
+extern const char vsyscall_int80_start, vsyscall_int80_end;
+extern const char vsyscall_sysenter_start, vsyscall_sysenter_end;
+
+int __init sysenter_setup(void)
+{
+ void *page = (void *)get_zeroed_page(GFP_ATOMIC);
+
+ __set_fixmap(FIX_VSYSCALL, __pa(page), PAGE_READONLY_EXEC);
+
+ if (!boot_cpu_has(X86_FEATURE_SEP)) {
+ memcpy(page,
+ &vsyscall_int80_start,
+ &vsyscall_int80_end - &vsyscall_int80_start);
+ return 0;
+ }
+
+ memcpy(page,
+ &vsyscall_sysenter_start,
+ &vsyscall_sysenter_end - &vsyscall_sysenter_start);
+
+ return 0;
+}
diff -r 3083585fb248 -r f97dd89691e7
linux-2.6-xen-sparse/arch/i386/kernel/vm86.c
--- /dev/null Mon Feb 20 14:08:39 2006
+++ b/linux-2.6-xen-sparse/arch/i386/kernel/vm86.c Mon Feb 20 14:37:13 2006
@@ -0,0 +1,809 @@
+/*
+ * linux/kernel/vm86.c
+ *
+ * Copyright (C) 1994 Linus Torvalds
+ *
+ * 29 dec 2001 - Fixed oopses caused by unchecked access to the vm86
+ * stack - Manfred Spraul <manfred@xxxxxxxxxxxxxxxx>
+ *
+ * 22 mar 2002 - Manfred detected the stackfaults, but didn't handle
+ * them correctly. Now the emulation will be in a
+ * consistent state after stackfaults - Kasper Dupont
+ * <kasperd@xxxxxxxxxxx>
+ *
+ * 22 mar 2002 - Added missing clear_IF in set_vflags_* Kasper Dupont
+ * <kasperd@xxxxxxxxxxx>
+ *
+ * ?? ??? 2002 - Fixed premature returns from handle_vm86_fault
+ * caused by Kasper Dupont's changes - Stas Sergeev
+ *
+ * 4 apr 2002 - Fixed CHECK_IF_IN_TRAP broken by Stas' changes.
+ * Kasper Dupont <kasperd@xxxxxxxxxxx>
+ *
+ * 9 apr 2002 - Changed syntax of macros in handle_vm86_fault.
+ * Kasper Dupont <kasperd@xxxxxxxxxxx>
+ *
+ * 9 apr 2002 - Changed stack access macros to jump to a label
+ * instead of returning to userspace. This simplifies
+ * do_int, and is needed by handle_vm6_fault. Kasper
+ * Dupont <kasperd@xxxxxxxxxxx>
+ *
+ */
+
+#include <linux/capability.h>
+#include <linux/config.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/signal.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/highmem.h>
+#include <linux/ptrace.h>
+
+#include <asm/uaccess.h>
+#include <asm/io.h>
+#include <asm/tlbflush.h>
+#include <asm/irq.h>
+
+/*
+ * Known problems:
+ *
+ * Interrupt handling is not guaranteed:
+ * - a real x86 will disable all interrupts for one instruction
+ * after a "mov ss,xx" to make stack handling atomic even without
+ * the 'lss' instruction. We can't guarantee this in v86 mode,
+ * as the next instruction might result in a page fault or similar.
+ * - a real x86 will have interrupts disabled for one instruction
+ * past the 'sti' that enables them. We don't bother with all the
+ * details yet.
+ *
+ * Let's hope these problems do not actually matter for anything.
+ */
+
+
+#define KVM86 ((struct kernel_vm86_struct *)regs)
+#define VMPI KVM86->vm86plus
+
+
+/*
+ * 8- and 16-bit register defines..
+ */
+#define AL(regs) (((unsigned char *)&((regs)->eax))[0])
+#define AH(regs) (((unsigned char *)&((regs)->eax))[1])
+#define IP(regs) (*(unsigned short *)&((regs)->eip))
+#define SP(regs) (*(unsigned short *)&((regs)->esp))
+
+/*
+ * virtual flags (16 and 32-bit versions)
+ */
+#define VFLAGS (*(unsigned short *)&(current->thread.v86flags))
+#define VEFLAGS (current->thread.v86flags)
+
+#define set_flags(X,new,mask) \
+((X) = ((X) & ~(mask)) | ((new) & (mask)))
+
+#define SAFE_MASK (0xDD5)
+#define RETURN_MASK (0xDFF)
+
+#define VM86_REGS_PART2 orig_eax
+#define VM86_REGS_SIZE1 \
+ ( (unsigned)( & (((struct kernel_vm86_regs *)0)->VM86_REGS_PART2) ) )
+#define VM86_REGS_SIZE2 (sizeof(struct kernel_vm86_regs) - VM86_REGS_SIZE1)
+
+struct pt_regs * FASTCALL(save_v86_state(struct kernel_vm86_regs * regs));
+struct pt_regs * fastcall save_v86_state(struct kernel_vm86_regs * regs)
+{
+ struct tss_struct *tss;
+ struct pt_regs *ret;
+ unsigned long tmp;
+
+ /*
+ * This gets called from entry.S with interrupts disabled, but
+ * from process context. Enable interrupts here, before trying
+ * to access user space.
+ */
+ local_irq_enable();
+
+ if (!current->thread.vm86_info) {
+ printk("no vm86_info: BAD\n");
+ do_exit(SIGSEGV);
+ }
+ set_flags(regs->eflags, VEFLAGS, VIF_MASK | current->thread.v86mask);
+ tmp = copy_to_user(¤t->thread.vm86_info->regs,regs,
VM86_REGS_SIZE1);
+ tmp += copy_to_user(¤t->thread.vm86_info->regs.VM86_REGS_PART2,
+ ®s->VM86_REGS_PART2, VM86_REGS_SIZE2);
+ tmp +=
put_user(current->thread.screen_bitmap,¤t->thread.vm86_info->screen_bitmap);
+ if (tmp) {
+ printk("vm86: could not access userspace vm86_info\n");
+ do_exit(SIGSEGV);
+ }
+
+ tss = &per_cpu(init_tss, get_cpu());
+ current->thread.esp0 = current->thread.saved_esp0;
+ current->thread.sysenter_cs = __KERNEL_CS;
+ load_esp0(tss, ¤t->thread);
+ current->thread.saved_esp0 = 0;
+ put_cpu();
+
+ loadsegment(fs, current->thread.saved_fs);
+ loadsegment(gs, current->thread.saved_gs);
+ ret = KVM86->regs32;
+ return ret;
+}
+
+static void mark_screen_rdonly(struct mm_struct *mm)
+{
+ pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmd;
+ pte_t *pte;
+ spinlock_t *ptl;
+ int i;
+
+ pgd = pgd_offset(mm, 0xA0000);
+ if (pgd_none_or_clear_bad(pgd))
+ goto out;
+ pud = pud_offset(pgd, 0xA0000);
+ if (pud_none_or_clear_bad(pud))
+ goto out;
+ pmd = pmd_offset(pud, 0xA0000);
+ if (pmd_none_or_clear_bad(pmd))
+ goto out;
+ pte = pte_offset_map_lock(mm, pmd, 0xA0000, &ptl);
+ for (i = 0; i < 32; i++) {
+ if (pte_present(*pte))
+ set_pte(pte, pte_wrprotect(*pte));
+ pte++;
+ }
+ pte_unmap_unlock(pte, ptl);
+out:
+ flush_tlb();
+}
+
+
+
+static int do_vm86_irq_handling(int subfunction, int irqnumber);
+static void do_sys_vm86(struct kernel_vm86_struct *info, struct task_struct
*tsk);
+
+asmlinkage int sys_vm86old(struct pt_regs regs)
+{
+ struct vm86_struct __user *v86 = (struct vm86_struct __user *)regs.ebx;
+ struct kernel_vm86_struct info; /* declare this _on top_,
+ * this avoids wasting of stack space.
+ * This remains on the stack until we
+ * return to 32 bit user space.
+ */
+ struct task_struct *tsk;
+ int tmp, ret = -EPERM;
+
+ tsk = current;
+ if (tsk->thread.saved_esp0)
+ goto out;
+ tmp = copy_from_user(&info, v86, VM86_REGS_SIZE1);
+ tmp += copy_from_user(&info.regs.VM86_REGS_PART2,
&v86->regs.VM86_REGS_PART2,
+ (long)&info.vm86plus - (long)&info.regs.VM86_REGS_PART2);
+ ret = -EFAULT;
+ if (tmp)
+ goto out;
+ memset(&info.vm86plus, 0, (int)&info.regs32 - (int)&info.vm86plus);
+ info.regs32 = ®s;
+ tsk->thread.vm86_info = v86;
+ do_sys_vm86(&info, tsk);
+ ret = 0; /* we never return here */
+out:
+ return ret;
+}
+
+
+asmlinkage int sys_vm86(struct pt_regs regs)
+{
+ struct kernel_vm86_struct info; /* declare this _on top_,
+ * this avoids wasting of stack space.
+ * This remains on the stack until we
+ * return to 32 bit user space.
+ */
+ struct task_struct *tsk;
+ int tmp, ret;
+ struct vm86plus_struct __user *v86;
+
+ tsk = current;
+ switch (regs.ebx) {
+ case VM86_REQUEST_IRQ:
+ case VM86_FREE_IRQ:
+ case VM86_GET_IRQ_BITS:
+ case VM86_GET_AND_RESET_IRQ:
+ ret = do_vm86_irq_handling(regs.ebx, (int)regs.ecx);
+ goto out;
+ case VM86_PLUS_INSTALL_CHECK:
+ /* NOTE: on old vm86 stuff this will return the error
+ from access_ok(), because the subfunction is
+ interpreted as (invalid) address to vm86_struct.
+ So the installation check works.
+ */
+ ret = 0;
+ goto out;
+ }
+
+ /* we come here only for functions VM86_ENTER, VM86_ENTER_NO_BYPASS */
+ ret = -EPERM;
+ if (tsk->thread.saved_esp0)
+ goto out;
+ v86 = (struct vm86plus_struct __user *)regs.ecx;
+ tmp = copy_from_user(&info, v86, VM86_REGS_SIZE1);
+ tmp += copy_from_user(&info.regs.VM86_REGS_PART2,
&v86->regs.VM86_REGS_PART2,
+ (long)&info.regs32 - (long)&info.regs.VM86_REGS_PART2);
+ ret = -EFAULT;
+ if (tmp)
+ goto out;
+ info.regs32 = ®s;
+ info.vm86plus.is_vm86pus = 1;
+ tsk->thread.vm86_info = (struct vm86_struct __user *)v86;
+ do_sys_vm86(&info, tsk);
+ ret = 0; /* we never return here */
+out:
+ return ret;
+}
+
+
+static void do_sys_vm86(struct kernel_vm86_struct *info, struct task_struct
*tsk)
+{
+ struct tss_struct *tss;
+/*
+ * make sure the vm86() system call doesn't try to do anything silly
+ */
+ info->regs.__null_ds = 0;
+ info->regs.__null_es = 0;
+
+/* we are clearing fs,gs later just before "jmp resume_userspace",
+ * because starting with Linux 2.1.x they aren't no longer saved/restored
+ */
+
+/*
+ * The eflags register is also special: we cannot trust that the user
+ * has set it up safely, so this makes sure interrupt etc flags are
+ * inherited from protected mode.
+ */
+ VEFLAGS = info->regs.eflags;
+ info->regs.eflags &= SAFE_MASK;
+ info->regs.eflags |= info->regs32->eflags & ~SAFE_MASK;
+ info->regs.eflags |= VM_MASK;
+
+ switch (info->cpu_type) {
+ case CPU_286:
+ tsk->thread.v86mask = 0;
+ break;
+ case CPU_386:
+ tsk->thread.v86mask = NT_MASK | IOPL_MASK;
+ break;
+ case CPU_486:
+ tsk->thread.v86mask = AC_MASK | NT_MASK | IOPL_MASK;
+ break;
+ default:
+ tsk->thread.v86mask = ID_MASK | AC_MASK | NT_MASK |
IOPL_MASK;
+ break;
+ }
+
+/*
+ * Save old state, set default return value (%eax) to 0
+ */
+ info->regs32->eax = 0;
+ tsk->thread.saved_esp0 = tsk->thread.esp0;
+ savesegment(fs, tsk->thread.saved_fs);
+ savesegment(gs, tsk->thread.saved_gs);
+
+ tss = &per_cpu(init_tss, get_cpu());
+ tsk->thread.esp0 = (unsigned long) &info->VM86_TSS_ESP0;
+ if (cpu_has_sep)
+ tsk->thread.sysenter_cs = 0;
+ load_esp0(tss, &tsk->thread);
+ put_cpu();
+
+ tsk->thread.screen_bitmap = info->screen_bitmap;
+ if (info->flags & VM86_SCREEN_BITMAP)
+ mark_screen_rdonly(tsk->mm);
+ __asm__ __volatile__(
+ "xorl %%eax,%%eax; movl %%eax,%%fs; movl %%eax,%%gs\n\t"
+ "movl %0,%%esp\n\t"
+ "movl %1,%%ebp\n\t"
+ "jmp resume_userspace"
+ : /* no outputs */
+ :"r" (&info->regs), "r" (task_thread_info(tsk)) : "ax");
+ /* we never return here */
+}
+
+static inline void return_to_32bit(struct kernel_vm86_regs * regs16, int
retval)
+{
+ struct pt_regs * regs32;
+
+ regs32 = save_v86_state(regs16);
+ regs32->eax = retval;
+ __asm__ __volatile__("movl %0,%%esp\n\t"
+ "movl %1,%%ebp\n\t"
+ "jmp resume_userspace"
+ : : "r" (regs32), "r" (current_thread_info()));
+}
+
+static inline void set_IF(struct kernel_vm86_regs * regs)
+{
+ VEFLAGS |= VIF_MASK;
+ if (VEFLAGS & VIP_MASK)
+ return_to_32bit(regs, VM86_STI);
+}
+
+static inline void clear_IF(struct kernel_vm86_regs * regs)
+{
+ VEFLAGS &= ~VIF_MASK;
+}
+
+static inline void clear_TF(struct kernel_vm86_regs * regs)
+{
+ regs->eflags &= ~TF_MASK;
+}
+
+static inline void clear_AC(struct kernel_vm86_regs * regs)
+{
+ regs->eflags &= ~AC_MASK;
+}
+
+/* It is correct to call set_IF(regs) from the set_vflags_*
+ * functions. However someone forgot to call clear_IF(regs)
+ * in the opposite case.
+ * After the command sequence CLI PUSHF STI POPF you should
+ * end up with interrups disabled, but you ended up with
+ * interrupts enabled.
+ * ( I was testing my own changes, but the only bug I
+ * could find was in a function I had not changed. )
+ * [KD]
+ */
+
+static inline void set_vflags_long(unsigned long eflags, struct
kernel_vm86_regs * regs)
+{
+ set_flags(VEFLAGS, eflags, current->thread.v86mask);
+ set_flags(regs->eflags, eflags, SAFE_MASK);
+ if (eflags & IF_MASK)
+ set_IF(regs);
+ else
+ clear_IF(regs);
+}
+
+static inline void set_vflags_short(unsigned short flags, struct
kernel_vm86_regs * regs)
+{
+ set_flags(VFLAGS, flags, current->thread.v86mask);
+ set_flags(regs->eflags, flags, SAFE_MASK);
+ if (flags & IF_MASK)
+ set_IF(regs);
+ else
+ clear_IF(regs);
+}
+
+static inline unsigned long get_vflags(struct kernel_vm86_regs * regs)
+{
+ unsigned long flags = regs->eflags & RETURN_MASK;
+
+ if (VEFLAGS & VIF_MASK)
+ flags |= IF_MASK;
+ flags |= IOPL_MASK;
+ return flags | (VEFLAGS & current->thread.v86mask);
+}
+
+static inline int is_revectored(int nr, struct revectored_struct * bitmap)
+{
+ __asm__ __volatile__("btl %2,%1\n\tsbbl %0,%0"
+ :"=r" (nr)
+ :"m" (*bitmap),"r" (nr));
+ return nr;
+}
+
+#define val_byte(val, n) (((__u8 *)&val)[n])
+
+#define pushb(base, ptr, val, err_label) \
+ do { \
+ __u8 __val = val; \
+ ptr--; \
+ if (put_user(__val, base + ptr) < 0) \
+ goto err_label; \
+ } while(0)
+
+#define pushw(base, ptr, val, err_label) \
+ do { \
+ __u16 __val = val; \
+ ptr--; \
+ if (put_user(val_byte(__val, 1), base + ptr) < 0) \
+ goto err_label; \
+ ptr--; \
+ if (put_user(val_byte(__val, 0), base + ptr) < 0) \
+ goto err_label; \
+ } while(0)
+
+#define pushl(base, ptr, val, err_label) \
+ do { \
+ __u32 __val = val; \
+ ptr--; \
+ if (put_user(val_byte(__val, 3), base + ptr) < 0) \
+ goto err_label; \
+ ptr--; \
+ if (put_user(val_byte(__val, 2), base + ptr) < 0) \
+ goto err_label; \
+ ptr--; \
+ if (put_user(val_byte(__val, 1), base + ptr) < 0) \
+ goto err_label; \
+ ptr--; \
+ if (put_user(val_byte(__val, 0), base + ptr) < 0) \
+ goto err_label; \
+ } while(0)
+
+#define popb(base, ptr, err_label) \
+ ({ \
+ __u8 __res; \
+ if (get_user(__res, base + ptr) < 0) \
+ goto err_label; \
+ ptr++; \
+ __res; \
+ })
+
+#define popw(base, ptr, err_label) \
+ ({ \
+ __u16 __res; \
+ if (get_user(val_byte(__res, 0), base + ptr) < 0) \
+ goto err_label; \
+ ptr++; \
+ if (get_user(val_byte(__res, 1), base + ptr) < 0) \
+ goto err_label; \
+ ptr++; \
+ __res; \
+ })
+
+#define popl(base, ptr, err_label) \
+ ({ \
+ __u32 __res; \
+ if (get_user(val_byte(__res, 0), base + ptr) < 0) \
+ goto err_label; \
+ ptr++; \
+ if (get_user(val_byte(__res, 1), base + ptr) < 0) \
+ goto err_label; \
+ ptr++; \
+ if (get_user(val_byte(__res, 2), base + ptr) < 0) \
+ goto err_label; \
+ ptr++; \
+ if (get_user(val_byte(__res, 3), base + ptr) < 0) \
+ goto err_label; \
+ ptr++; \
+ __res; \
+ })
+
+/* There are so many possible reasons for this function to return
+ * VM86_INTx, so adding another doesn't bother me. We can expect
+ * userspace programs to be able to handle it. (Getting a problem
+ * in userspace is always better than an Oops anyway.) [KD]
+ */
+static void do_int(struct kernel_vm86_regs *regs, int i,
+ unsigned char __user * ssp, unsigned short sp)
+{
+ unsigned long __user *intr_ptr;
+ unsigned long segoffs;
+
+ if (regs->cs == BIOSSEG)
+ goto cannot_handle;
+ if (is_revectored(i, &KVM86->int_revectored))
+ goto cannot_handle;
+ if (i==0x21 && is_revectored(AH(regs),&KVM86->int21_revectored))
+ goto cannot_handle;
+ intr_ptr = (unsigned long __user *) (i << 2);
+ if (get_user(segoffs, intr_ptr))
+ goto cannot_handle;
+ if ((segoffs >> 16) == BIOSSEG)
+ goto cannot_handle;
+ pushw(ssp, sp, get_vflags(regs), cannot_handle);
+ pushw(ssp, sp, regs->cs, cannot_handle);
+ pushw(ssp, sp, IP(regs), cannot_handle);
+ regs->cs = segoffs >> 16;
+ SP(regs) -= 6;
+ IP(regs) = segoffs & 0xffff;
+ clear_TF(regs);
+ clear_IF(regs);
+ clear_AC(regs);
+ return;
+
+cannot_handle:
+ return_to_32bit(regs, VM86_INTx + (i << 8));
+}
+
+int handle_vm86_trap(struct kernel_vm86_regs * regs, long error_code, int
trapno)
+{
+ if (VMPI.is_vm86pus) {
+ if ( (trapno==3) || (trapno==1) )
+ return_to_32bit(regs, VM86_TRAP + (trapno << 8));
+ do_int(regs, trapno, (unsigned char __user *) (regs->ss << 4),
SP(regs));
+ return 0;
+ }
+ if (trapno !=1)
+ return 1; /* we let this handle by the calling routine */
+ if (current->ptrace & PT_PTRACED) {
+ unsigned long flags;
+ spin_lock_irqsave(¤t->sighand->siglock, flags);
+ sigdelset(¤t->blocked, SIGTRAP);
+ recalc_sigpending();
+ spin_unlock_irqrestore(¤t->sighand->siglock, flags);
+ }
+ send_sig(SIGTRAP, current, 1);
+ current->thread.trap_no = trapno;
+ current->thread.error_code = error_code;
+ return 0;
+}
+
+void handle_vm86_fault(struct kernel_vm86_regs * regs, long error_code)
+{
+ unsigned char opcode;
+ unsigned char __user *csp;
+ unsigned char __user *ssp;
+ unsigned short ip, sp, orig_flags;
+ int data32, pref_done;
+
+#define CHECK_IF_IN_TRAP \
+ if (VMPI.vm86dbg_active && VMPI.vm86dbg_TFpendig) \
+ newflags |= TF_MASK
+#define VM86_FAULT_RETURN do { \
+ if (VMPI.force_return_for_pic && (VEFLAGS & (IF_MASK | VIF_MASK))) \
+ return_to_32bit(regs, VM86_PICRETURN); \
+ if (orig_flags & TF_MASK) \
+ handle_vm86_trap(regs, 0, 1); \
+ return; } while (0)
+
+ orig_flags = *(unsigned short *)®s->eflags;
+
+ csp = (unsigned char __user *) (regs->cs << 4);
+ ssp = (unsigned char __user *) (regs->ss << 4);
+ sp = SP(regs);
+ ip = IP(regs);
+
+ data32 = 0;
+ pref_done = 0;
+ do {
+ switch (opcode = popb(csp, ip, simulate_sigsegv)) {
+ case 0x66: /* 32-bit data */ data32=1; break;
+ case 0x67: /* 32-bit address */ break;
+ case 0x2e: /* CS */ break;
+ case 0x3e: /* DS */ break;
+ case 0x26: /* ES */ break;
+ case 0x36: /* SS */ break;
+ case 0x65: /* GS */ break;
+ case 0x64: /* FS */ break;
+ case 0xf2: /* repnz */ break;
+ case 0xf3: /* rep */ break;
+ default: pref_done = 1;
+ }
+ } while (!pref_done);
+
+ switch (opcode) {
+
+ /* pushf */
+ case 0x9c:
+ if (data32) {
+ pushl(ssp, sp, get_vflags(regs), simulate_sigsegv);
+ SP(regs) -= 4;
+ } else {
+ pushw(ssp, sp, get_vflags(regs), simulate_sigsegv);
+ SP(regs) -= 2;
+ }
+ IP(regs) = ip;
+ VM86_FAULT_RETURN;
+
+ /* popf */
+ case 0x9d:
+ {
+ unsigned long newflags;
+ if (data32) {
+ newflags=popl(ssp, sp, simulate_sigsegv);
+ SP(regs) += 4;
+ } else {
+ newflags = popw(ssp, sp, simulate_sigsegv);
+ SP(regs) += 2;
+ }
+ IP(regs) = ip;
+ CHECK_IF_IN_TRAP;
+ if (data32) {
+ set_vflags_long(newflags, regs);
+ } else {
+ set_vflags_short(newflags, regs);
+ }
+ VM86_FAULT_RETURN;
+ }
+
+ /* int xx */
+ case 0xcd: {
+ int intno=popb(csp, ip, simulate_sigsegv);
+ IP(regs) = ip;
+ if (VMPI.vm86dbg_active) {
+ if ( (1 << (intno &7)) & VMPI.vm86dbg_intxxtab[intno >>
3] )
+ return_to_32bit(regs, VM86_INTx + (intno << 8));
+ }
+ do_int(regs, intno, ssp, sp);
+ return;
+ }
+
+ /* iret */
+ case 0xcf:
+ {
+ unsigned long newip;
+ unsigned long newcs;
+ unsigned long newflags;
+ if (data32) {
+ newip=popl(ssp, sp, simulate_sigsegv);
+ newcs=popl(ssp, sp, simulate_sigsegv);
+ newflags=popl(ssp, sp, simulate_sigsegv);
+ SP(regs) += 12;
+ } else {
+ newip = popw(ssp, sp, simulate_sigsegv);
+ newcs = popw(ssp, sp, simulate_sigsegv);
+ newflags = popw(ssp, sp, simulate_sigsegv);
+ SP(regs) += 6;
+ }
+ IP(regs) = newip;
+ regs->cs = newcs;
+ CHECK_IF_IN_TRAP;
+ if (data32) {
+ set_vflags_long(newflags, regs);
+ } else {
+ set_vflags_short(newflags, regs);
+ }
+ VM86_FAULT_RETURN;
+ }
+
+ /* cli */
+ case 0xfa:
+ IP(regs) = ip;
+ clear_IF(regs);
+ VM86_FAULT_RETURN;
+
+ /* sti */
+ /*
+ * Damn. This is incorrect: the 'sti' instruction should actually
+ * enable interrupts after the /next/ instruction. Not good.
+ *
+ * Probably needs some horsing around with the TF flag. Aiee..
+ */
+ case 0xfb:
+ IP(regs) = ip;
+ set_IF(regs);
+ VM86_FAULT_RETURN;
+
+ default:
+ return_to_32bit(regs, VM86_UNKNOWN);
+ }
+
+ return;
+
+simulate_sigsegv:
+ /* FIXME: After a long discussion with Stas we finally
+ * agreed, that this is wrong. Here we should
+ * really send a SIGSEGV to the user program.
+ * But how do we create the correct context? We
+ * are inside a general protection fault handler
+ * and has just returned from a page fault handler.
+ * The correct context for the signal handler
+ * should be a mixture of the two, but how do we
+ * get the information? [KD]
+ */
+ return_to_32bit(regs, VM86_UNKNOWN);
+}
+
+/* ---------------- vm86 special IRQ passing stuff ----------------- */
+
+#define VM86_IRQNAME "vm86irq"
+
+static struct vm86_irqs {
+ struct task_struct *tsk;
+ int sig;
+} vm86_irqs[16];
+
+static DEFINE_SPINLOCK(irqbits_lock);
+static int irqbits;
+
+#define ALLOWED_SIGS ( 1 /* 0 = don't send a signal */ \
+ | (1 << SIGUSR1) | (1 << SIGUSR2) | (1 << SIGIO) | (1 << SIGURG) \
+ | (1 << SIGUNUSED) )
+
+static irqreturn_t irq_handler(int intno, void *dev_id, struct pt_regs * regs)
+{
+ int irq_bit;
+ unsigned long flags;
+
+ spin_lock_irqsave(&irqbits_lock, flags);
+ irq_bit = 1 << intno;
+ if ((irqbits & irq_bit) || ! vm86_irqs[intno].tsk)
+ goto out;
+ irqbits |= irq_bit;
+ if (vm86_irqs[intno].sig)
+ send_sig(vm86_irqs[intno].sig, vm86_irqs[intno].tsk, 1);
+ /*
+ * IRQ will be re-enabled when user asks for the irq (whether
+ * polling or as a result of the signal)
+ */
+ disable_irq_nosync(intno);
+ spin_unlock_irqrestore(&irqbits_lock, flags);
+ return IRQ_HANDLED;
+
+out:
+ spin_unlock_irqrestore(&irqbits_lock, flags);
+ return IRQ_NONE;
+}
+
+static inline void free_vm86_irq(int irqnumber)
+{
+ unsigned long flags;
+
+ free_irq(irqnumber, NULL);
+ vm86_irqs[irqnumber].tsk = NULL;
+
+ spin_lock_irqsave(&irqbits_lock, flags);
+ irqbits &= ~(1 << irqnumber);
+ spin_unlock_irqrestore(&irqbits_lock, flags);
+}
+
+void release_vm86_irqs(struct task_struct *task)
+{
+ int i;
+ for (i = FIRST_VM86_IRQ ; i <= LAST_VM86_IRQ; i++)
+ if (vm86_irqs[i].tsk == task)
+ free_vm86_irq(i);
+}
+
+static inline int get_and_reset_irq(int irqnumber)
+{
+ int bit;
+ unsigned long flags;
+ int ret = 0;
+
+ if (invalid_vm86_irq(irqnumber)) return 0;
+ if (vm86_irqs[irqnumber].tsk != current) return 0;
+ spin_lock_irqsave(&irqbits_lock, flags);
+ bit = irqbits & (1 << irqnumber);
+ irqbits &= ~bit;
+ if (bit) {
+ enable_irq(irqnumber);
+ ret = 1;
+ }
+
+ spin_unlock_irqrestore(&irqbits_lock, flags);
+ return ret;
+}
+
+
+static int do_vm86_irq_handling(int subfunction, int irqnumber)
+{
+ int ret;
+ switch (subfunction) {
+ case VM86_GET_AND_RESET_IRQ: {
+ return get_and_reset_irq(irqnumber);
+ }
+ case VM86_GET_IRQ_BITS: {
+ return irqbits;
+ }
+ case VM86_REQUEST_IRQ: {
+ int sig = irqnumber >> 8;
+ int irq = irqnumber & 255;
+ if (!capable(CAP_SYS_ADMIN)) return -EPERM;
+ if (!((1 << sig) & ALLOWED_SIGS)) return -EPERM;
+ if (invalid_vm86_irq(irq)) return -EPERM;
+ if (vm86_irqs[irq].tsk) return -EPERM;
+ ret = request_irq(irq, &irq_handler, 0, VM86_IRQNAME,
NULL);
+ if (ret) return ret;
+ vm86_irqs[irq].sig = sig;
+ vm86_irqs[irq].tsk = current;
+ return irq;
+ }
+ case VM86_FREE_IRQ: {
+ if (invalid_vm86_irq(irqnumber)) return -EPERM;
+ if (!vm86_irqs[irqnumber].tsk) return 0;
+ if (vm86_irqs[irqnumber].tsk != current) return -EPERM;
+ free_vm86_irq(irqnumber);
+ return 0;
+ }
+ }
+ return -EINVAL;
+}
+
diff -r 3083585fb248 -r f97dd89691e7
linux-2.6-xen-sparse/arch/i386/kernel/vsyscall.S
--- /dev/null Mon Feb 20 14:08:39 2006
+++ b/linux-2.6-xen-sparse/arch/i386/kernel/vsyscall.S Mon Feb 20 14:37:13 2006
@@ -0,0 +1,15 @@
+#include <linux/init.h>
+
+__INITDATA
+
+ .globl vsyscall_int80_start, vsyscall_int80_end
+vsyscall_int80_start:
+ .incbin "arch/i386/kernel/vsyscall-int80.so"
+vsyscall_int80_end:
+
+ .globl vsyscall_sysenter_start, vsyscall_sysenter_end
+vsyscall_sysenter_start:
+ .incbin "arch/i386/kernel/vsyscall-sysenter.so"
+vsyscall_sysenter_end:
+
+__FINIT
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