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Diffstat (limited to 'ANDROID_3.4.5/arch/x86/kernel/process_64.c')
-rw-r--r--ANDROID_3.4.5/arch/x86/kernel/process_64.c556
1 files changed, 556 insertions, 0 deletions
diff --git a/ANDROID_3.4.5/arch/x86/kernel/process_64.c b/ANDROID_3.4.5/arch/x86/kernel/process_64.c
new file mode 100644
index 00000000..43d8b48b
--- /dev/null
+++ b/ANDROID_3.4.5/arch/x86/kernel/process_64.c
@@ -0,0 +1,556 @@
+/*
+ * Copyright (C) 1995 Linus Torvalds
+ *
+ * Pentium III FXSR, SSE support
+ * Gareth Hughes <gareth@valinux.com>, May 2000
+ *
+ * X86-64 port
+ * Andi Kleen.
+ *
+ * CPU hotplug support - ashok.raj@intel.com
+ */
+
+/*
+ * This file handles the architecture-dependent parts of process handling..
+ */
+
+#include <linux/cpu.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/fs.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/elfcore.h>
+#include <linux/smp.h>
+#include <linux/slab.h>
+#include <linux/user.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/ptrace.h>
+#include <linux/notifier.h>
+#include <linux/kprobes.h>
+#include <linux/kdebug.h>
+#include <linux/prctl.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
+#include <linux/ftrace.h>
+
+#include <asm/pgtable.h>
+#include <asm/processor.h>
+#include <asm/i387.h>
+#include <asm/fpu-internal.h>
+#include <asm/mmu_context.h>
+#include <asm/prctl.h>
+#include <asm/desc.h>
+#include <asm/proto.h>
+#include <asm/ia32.h>
+#include <asm/idle.h>
+#include <asm/syscalls.h>
+#include <asm/debugreg.h>
+#include <asm/switch_to.h>
+
+asmlinkage extern void ret_from_fork(void);
+
+DEFINE_PER_CPU(unsigned long, old_rsp);
+
+/* Prints also some state that isn't saved in the pt_regs */
+void __show_regs(struct pt_regs *regs, int all)
+{
+ unsigned long cr0 = 0L, cr2 = 0L, cr3 = 0L, cr4 = 0L, fs, gs, shadowgs;
+ unsigned long d0, d1, d2, d3, d6, d7;
+ unsigned int fsindex, gsindex;
+ unsigned int ds, cs, es;
+
+ show_regs_common();
+ printk(KERN_DEFAULT "RIP: %04lx:[<%016lx>] ", regs->cs & 0xffff, regs->ip);
+ printk_address(regs->ip, 1);
+ printk(KERN_DEFAULT "RSP: %04lx:%016lx EFLAGS: %08lx\n", regs->ss,
+ regs->sp, regs->flags);
+ printk(KERN_DEFAULT "RAX: %016lx RBX: %016lx RCX: %016lx\n",
+ regs->ax, regs->bx, regs->cx);
+ printk(KERN_DEFAULT "RDX: %016lx RSI: %016lx RDI: %016lx\n",
+ regs->dx, regs->si, regs->di);
+ printk(KERN_DEFAULT "RBP: %016lx R08: %016lx R09: %016lx\n",
+ regs->bp, regs->r8, regs->r9);
+ printk(KERN_DEFAULT "R10: %016lx R11: %016lx R12: %016lx\n",
+ regs->r10, regs->r11, regs->r12);
+ printk(KERN_DEFAULT "R13: %016lx R14: %016lx R15: %016lx\n",
+ regs->r13, regs->r14, regs->r15);
+
+ asm("movl %%ds,%0" : "=r" (ds));
+ asm("movl %%cs,%0" : "=r" (cs));
+ asm("movl %%es,%0" : "=r" (es));
+ asm("movl %%fs,%0" : "=r" (fsindex));
+ asm("movl %%gs,%0" : "=r" (gsindex));
+
+ rdmsrl(MSR_FS_BASE, fs);
+ rdmsrl(MSR_GS_BASE, gs);
+ rdmsrl(MSR_KERNEL_GS_BASE, shadowgs);
+
+ if (!all)
+ return;
+
+ cr0 = read_cr0();
+ cr2 = read_cr2();
+ cr3 = read_cr3();
+ cr4 = read_cr4();
+
+ printk(KERN_DEFAULT "FS: %016lx(%04x) GS:%016lx(%04x) knlGS:%016lx\n",
+ fs, fsindex, gs, gsindex, shadowgs);
+ printk(KERN_DEFAULT "CS: %04x DS: %04x ES: %04x CR0: %016lx\n", cs, ds,
+ es, cr0);
+ printk(KERN_DEFAULT "CR2: %016lx CR3: %016lx CR4: %016lx\n", cr2, cr3,
+ cr4);
+
+ get_debugreg(d0, 0);
+ get_debugreg(d1, 1);
+ get_debugreg(d2, 2);
+ printk(KERN_DEFAULT "DR0: %016lx DR1: %016lx DR2: %016lx\n", d0, d1, d2);
+ get_debugreg(d3, 3);
+ get_debugreg(d6, 6);
+ get_debugreg(d7, 7);
+ printk(KERN_DEFAULT "DR3: %016lx DR6: %016lx DR7: %016lx\n", d3, d6, d7);
+}
+
+void release_thread(struct task_struct *dead_task)
+{
+ if (dead_task->mm) {
+ if (dead_task->mm->context.size) {
+ printk("WARNING: dead process %8s still has LDT? <%p/%d>\n",
+ dead_task->comm,
+ dead_task->mm->context.ldt,
+ dead_task->mm->context.size);
+ BUG();
+ }
+ }
+}
+
+static inline void set_32bit_tls(struct task_struct *t, int tls, u32 addr)
+{
+ struct user_desc ud = {
+ .base_addr = addr,
+ .limit = 0xfffff,
+ .seg_32bit = 1,
+ .limit_in_pages = 1,
+ .useable = 1,
+ };
+ struct desc_struct *desc = t->thread.tls_array;
+ desc += tls;
+ fill_ldt(desc, &ud);
+}
+
+static inline u32 read_32bit_tls(struct task_struct *t, int tls)
+{
+ return get_desc_base(&t->thread.tls_array[tls]);
+}
+
+/*
+ * This gets called before we allocate a new thread and copy
+ * the current task into it.
+ */
+void prepare_to_copy(struct task_struct *tsk)
+{
+ unlazy_fpu(tsk);
+}
+
+int copy_thread(unsigned long clone_flags, unsigned long sp,
+ unsigned long unused,
+ struct task_struct *p, struct pt_regs *regs)
+{
+ int err;
+ struct pt_regs *childregs;
+ struct task_struct *me = current;
+
+ childregs = ((struct pt_regs *)
+ (THREAD_SIZE + task_stack_page(p))) - 1;
+ *childregs = *regs;
+
+ childregs->ax = 0;
+ if (user_mode(regs))
+ childregs->sp = sp;
+ else
+ childregs->sp = (unsigned long)childregs;
+
+ p->thread.sp = (unsigned long) childregs;
+ p->thread.sp0 = (unsigned long) (childregs+1);
+ p->thread.usersp = me->thread.usersp;
+
+ set_tsk_thread_flag(p, TIF_FORK);
+
+ p->fpu_counter = 0;
+ p->thread.io_bitmap_ptr = NULL;
+
+ savesegment(gs, p->thread.gsindex);
+ p->thread.gs = p->thread.gsindex ? 0 : me->thread.gs;
+ savesegment(fs, p->thread.fsindex);
+ p->thread.fs = p->thread.fsindex ? 0 : me->thread.fs;
+ savesegment(es, p->thread.es);
+ savesegment(ds, p->thread.ds);
+
+ err = -ENOMEM;
+ memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps));
+
+ if (unlikely(test_tsk_thread_flag(me, TIF_IO_BITMAP))) {
+ p->thread.io_bitmap_ptr = kmemdup(me->thread.io_bitmap_ptr,
+ IO_BITMAP_BYTES, GFP_KERNEL);
+ if (!p->thread.io_bitmap_ptr) {
+ p->thread.io_bitmap_max = 0;
+ return -ENOMEM;
+ }
+ set_tsk_thread_flag(p, TIF_IO_BITMAP);
+ }
+
+ /*
+ * Set a new TLS for the child thread?
+ */
+ if (clone_flags & CLONE_SETTLS) {
+#ifdef CONFIG_IA32_EMULATION
+ if (test_thread_flag(TIF_IA32))
+ err = do_set_thread_area(p, -1,
+ (struct user_desc __user *)childregs->si, 0);
+ else
+#endif
+ err = do_arch_prctl(p, ARCH_SET_FS, childregs->r8);
+ if (err)
+ goto out;
+ }
+ err = 0;
+out:
+ if (err && p->thread.io_bitmap_ptr) {
+ kfree(p->thread.io_bitmap_ptr);
+ p->thread.io_bitmap_max = 0;
+ }
+
+ return err;
+}
+
+static void
+start_thread_common(struct pt_regs *regs, unsigned long new_ip,
+ unsigned long new_sp,
+ unsigned int _cs, unsigned int _ss, unsigned int _ds)
+{
+ loadsegment(fs, 0);
+ loadsegment(es, _ds);
+ loadsegment(ds, _ds);
+ load_gs_index(0);
+ current->thread.usersp = new_sp;
+ regs->ip = new_ip;
+ regs->sp = new_sp;
+ percpu_write(old_rsp, new_sp);
+ regs->cs = _cs;
+ regs->ss = _ss;
+ regs->flags = X86_EFLAGS_IF;
+ /*
+ * Free the old FP and other extended state
+ */
+ free_thread_xstate(current);
+}
+
+void
+start_thread(struct pt_regs *regs, unsigned long new_ip, unsigned long new_sp)
+{
+ start_thread_common(regs, new_ip, new_sp,
+ __USER_CS, __USER_DS, 0);
+}
+
+#ifdef CONFIG_IA32_EMULATION
+void start_thread_ia32(struct pt_regs *regs, u32 new_ip, u32 new_sp)
+{
+ start_thread_common(regs, new_ip, new_sp,
+ test_thread_flag(TIF_X32)
+ ? __USER_CS : __USER32_CS,
+ __USER_DS, __USER_DS);
+}
+#endif
+
+/*
+ * switch_to(x,y) should switch tasks from x to y.
+ *
+ * This could still be optimized:
+ * - fold all the options into a flag word and test it with a single test.
+ * - could test fs/gs bitsliced
+ *
+ * Kprobes not supported here. Set the probe on schedule instead.
+ * Function graph tracer not supported too.
+ */
+__notrace_funcgraph struct task_struct *
+__switch_to(struct task_struct *prev_p, struct task_struct *next_p)
+{
+ struct thread_struct *prev = &prev_p->thread;
+ struct thread_struct *next = &next_p->thread;
+ int cpu = smp_processor_id();
+ struct tss_struct *tss = &per_cpu(init_tss, cpu);
+ unsigned fsindex, gsindex;
+ fpu_switch_t fpu;
+
+ fpu = switch_fpu_prepare(prev_p, next_p, cpu);
+
+ /*
+ * Reload esp0, LDT and the page table pointer:
+ */
+ load_sp0(tss, next);
+
+ /*
+ * Switch DS and ES.
+ * This won't pick up thread selector changes, but I guess that is ok.
+ */
+ savesegment(es, prev->es);
+ if (unlikely(next->es | prev->es))
+ loadsegment(es, next->es);
+
+ savesegment(ds, prev->ds);
+ if (unlikely(next->ds | prev->ds))
+ loadsegment(ds, next->ds);
+
+
+ /* We must save %fs and %gs before load_TLS() because
+ * %fs and %gs may be cleared by load_TLS().
+ *
+ * (e.g. xen_load_tls())
+ */
+ savesegment(fs, fsindex);
+ savesegment(gs, gsindex);
+
+ load_TLS(next, cpu);
+
+ /*
+ * Leave lazy mode, flushing any hypercalls made here.
+ * This must be done before restoring TLS segments so
+ * the GDT and LDT are properly updated, and must be
+ * done before math_state_restore, so the TS bit is up
+ * to date.
+ */
+ arch_end_context_switch(next_p);
+
+ /*
+ * Switch FS and GS.
+ *
+ * Segment register != 0 always requires a reload. Also
+ * reload when it has changed. When prev process used 64bit
+ * base always reload to avoid an information leak.
+ */
+ if (unlikely(fsindex | next->fsindex | prev->fs)) {
+ loadsegment(fs, next->fsindex);
+ /*
+ * Check if the user used a selector != 0; if yes
+ * clear 64bit base, since overloaded base is always
+ * mapped to the Null selector
+ */
+ if (fsindex)
+ prev->fs = 0;
+ }
+ /* when next process has a 64bit base use it */
+ if (next->fs)
+ wrmsrl(MSR_FS_BASE, next->fs);
+ prev->fsindex = fsindex;
+
+ if (unlikely(gsindex | next->gsindex | prev->gs)) {
+ load_gs_index(next->gsindex);
+ if (gsindex)
+ prev->gs = 0;
+ }
+ if (next->gs)
+ wrmsrl(MSR_KERNEL_GS_BASE, next->gs);
+ prev->gsindex = gsindex;
+
+ switch_fpu_finish(next_p, fpu);
+
+ /*
+ * Switch the PDA and FPU contexts.
+ */
+ prev->usersp = percpu_read(old_rsp);
+ percpu_write(old_rsp, next->usersp);
+ percpu_write(current_task, next_p);
+
+ percpu_write(kernel_stack,
+ (unsigned long)task_stack_page(next_p) +
+ THREAD_SIZE - KERNEL_STACK_OFFSET);
+
+ /*
+ * Now maybe reload the debug registers and handle I/O bitmaps
+ */
+ if (unlikely(task_thread_info(next_p)->flags & _TIF_WORK_CTXSW_NEXT ||
+ task_thread_info(prev_p)->flags & _TIF_WORK_CTXSW_PREV))
+ __switch_to_xtra(prev_p, next_p, tss);
+
+ return prev_p;
+}
+
+void set_personality_64bit(void)
+{
+ /* inherit personality from parent */
+
+ /* Make sure to be in 64bit mode */
+ clear_thread_flag(TIF_IA32);
+ clear_thread_flag(TIF_ADDR32);
+ clear_thread_flag(TIF_X32);
+
+ /* Ensure the corresponding mm is not marked. */
+ if (current->mm)
+ current->mm->context.ia32_compat = 0;
+
+ /* TBD: overwrites user setup. Should have two bits.
+ But 64bit processes have always behaved this way,
+ so it's not too bad. The main problem is just that
+ 32bit childs are affected again. */
+ current->personality &= ~READ_IMPLIES_EXEC;
+}
+
+void set_personality_ia32(bool x32)
+{
+ /* inherit personality from parent */
+
+ /* Make sure to be in 32bit mode */
+ set_thread_flag(TIF_ADDR32);
+
+ /* Mark the associated mm as containing 32-bit tasks. */
+ if (current->mm)
+ current->mm->context.ia32_compat = 1;
+
+ if (x32) {
+ clear_thread_flag(TIF_IA32);
+ set_thread_flag(TIF_X32);
+ current->personality &= ~READ_IMPLIES_EXEC;
+ /* is_compat_task() uses the presence of the x32
+ syscall bit flag to determine compat status */
+ current_thread_info()->status &= ~TS_COMPAT;
+ } else {
+ set_thread_flag(TIF_IA32);
+ clear_thread_flag(TIF_X32);
+ current->personality |= force_personality32;
+ /* Prepare the first "return" to user space */
+ current_thread_info()->status |= TS_COMPAT;
+ }
+}
+EXPORT_SYMBOL_GPL(set_personality_ia32);
+
+unsigned long get_wchan(struct task_struct *p)
+{
+ unsigned long stack;
+ u64 fp, ip;
+ int count = 0;
+
+ if (!p || p == current || p->state == TASK_RUNNING)
+ return 0;
+ stack = (unsigned long)task_stack_page(p);
+ if (p->thread.sp < stack || p->thread.sp >= stack+THREAD_SIZE)
+ return 0;
+ fp = *(u64 *)(p->thread.sp);
+ do {
+ if (fp < (unsigned long)stack ||
+ fp >= (unsigned long)stack+THREAD_SIZE)
+ return 0;
+ ip = *(u64 *)(fp+8);
+ if (!in_sched_functions(ip))
+ return ip;
+ fp = *(u64 *)fp;
+ } while (count++ < 16);
+ return 0;
+}
+
+long do_arch_prctl(struct task_struct *task, int code, unsigned long addr)
+{
+ int ret = 0;
+ int doit = task == current;
+ int cpu;
+
+ switch (code) {
+ case ARCH_SET_GS:
+ if (addr >= TASK_SIZE_OF(task))
+ return -EPERM;
+ cpu = get_cpu();
+ /* handle small bases via the GDT because that's faster to
+ switch. */
+ if (addr <= 0xffffffff) {
+ set_32bit_tls(task, GS_TLS, addr);
+ if (doit) {
+ load_TLS(&task->thread, cpu);
+ load_gs_index(GS_TLS_SEL);
+ }
+ task->thread.gsindex = GS_TLS_SEL;
+ task->thread.gs = 0;
+ } else {
+ task->thread.gsindex = 0;
+ task->thread.gs = addr;
+ if (doit) {
+ load_gs_index(0);
+ ret = checking_wrmsrl(MSR_KERNEL_GS_BASE, addr);
+ }
+ }
+ put_cpu();
+ break;
+ case ARCH_SET_FS:
+ /* Not strictly needed for fs, but do it for symmetry
+ with gs */
+ if (addr >= TASK_SIZE_OF(task))
+ return -EPERM;
+ cpu = get_cpu();
+ /* handle small bases via the GDT because that's faster to
+ switch. */
+ if (addr <= 0xffffffff) {
+ set_32bit_tls(task, FS_TLS, addr);
+ if (doit) {
+ load_TLS(&task->thread, cpu);
+ loadsegment(fs, FS_TLS_SEL);
+ }
+ task->thread.fsindex = FS_TLS_SEL;
+ task->thread.fs = 0;
+ } else {
+ task->thread.fsindex = 0;
+ task->thread.fs = addr;
+ if (doit) {
+ /* set the selector to 0 to not confuse
+ __switch_to */
+ loadsegment(fs, 0);
+ ret = checking_wrmsrl(MSR_FS_BASE, addr);
+ }
+ }
+ put_cpu();
+ break;
+ case ARCH_GET_FS: {
+ unsigned long base;
+ if (task->thread.fsindex == FS_TLS_SEL)
+ base = read_32bit_tls(task, FS_TLS);
+ else if (doit)
+ rdmsrl(MSR_FS_BASE, base);
+ else
+ base = task->thread.fs;
+ ret = put_user(base, (unsigned long __user *)addr);
+ break;
+ }
+ case ARCH_GET_GS: {
+ unsigned long base;
+ unsigned gsindex;
+ if (task->thread.gsindex == GS_TLS_SEL)
+ base = read_32bit_tls(task, GS_TLS);
+ else if (doit) {
+ savesegment(gs, gsindex);
+ if (gsindex)
+ rdmsrl(MSR_KERNEL_GS_BASE, base);
+ else
+ base = task->thread.gs;
+ } else
+ base = task->thread.gs;
+ ret = put_user(base, (unsigned long __user *)addr);
+ break;
+ }
+
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ return ret;
+}
+
+long sys_arch_prctl(int code, unsigned long addr)
+{
+ return do_arch_prctl(current, code, addr);
+}
+
+unsigned long KSTK_ESP(struct task_struct *task)
+{
+ return (test_tsk_thread_flag(task, TIF_IA32)) ?
+ (task_pt_regs(task)->sp) : ((task)->thread.usersp);
+}
generated by cgit (git 2.34.1) at 2025-01-11 03:01:27 +0000