arch/um/kernel/frame_kern.c

   1 /*
   2  * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #include "asm/ptrace.h"
   7 #include "asm/uaccess.h"
   8 #include "asm/signal.h"
   9 #include "asm/uaccess.h"
  10 #include "asm/ucontext.h"
  11 #include "frame_kern.h"
  12 #include "sigcontext.h"
  13 #include "sysdep/ptrace.h"
  14 #include "choose-mode.h"
  15 #include "mode.h"
  16
  17 static int copy_restorer(void (*restorer)(void), unsigned long start,
  18                          unsigned long sr_index, int sr_relative)
  19 {
  20         unsigned long sr;
  21
  22         if(sr_relative){
  23                 sr = (unsigned long) restorer;
  24                 sr += start + sr_index;
  25                 restorer = (void (*)(void)) sr;
  26         }
  27
  28         return(copy_to_user((void *) (start + sr_index), &restorer,
  29                             sizeof(restorer)));
  30 }
  31
  32 static int copy_sc_to_user(void *to, void *fp, struct pt_regs *from,
  33                            struct arch_frame_data *arch)
  34 {
  35         return(CHOOSE_MODE(copy_sc_to_user_tt(to, fp, UPT_SC(&from->regs),
  36                                               arch),
  37                            copy_sc_to_user_skas(to, fp, &from->regs,
  38                                                 current->thread.cr2,
  39                                                 current->thread.err)));
  40 }
  41
  42 static int copy_ucontext_to_user(struct ucontext *uc, void *fp, sigset_t *set,
  43                                  unsigned long sp)
  44 {
  45         int err = 0;
  46
  47         err |= put_user(current->sas_ss_sp, &uc->uc_stack.ss_sp);
  48         err |= put_user(sas_ss_flags(sp), &uc->uc_stack.ss_flags);
  49         err |= put_user(current->sas_ss_size, &uc->uc_stack.ss_size);
  50         err |= copy_sc_to_user(&uc->uc_mcontext, fp, &current->thread.regs,
  51                                &signal_frame_si.common.arch);
  52         err |= copy_to_user(&uc->uc_sigmask, set, sizeof(*set));
  53         return(err);
  54 }
  55
  56 int setup_signal_stack_si(unsigned long stack_top, int sig,
  57                           unsigned long handler, void (*restorer)(void),
  58                           struct pt_regs *regs, siginfo_t *info,
  59                           sigset_t *mask)
  60 {
  61         unsigned long start;
  62         void *sip, *ucp, *fp;
  63
  64         start = stack_top - signal_frame_si.common.len;
  65         sip = (void *) (start + signal_frame_si.si_index);
  66         ucp = (void *) (start + signal_frame_si.uc_index);
  67         fp = (void *) (((unsigned long) ucp) + sizeof(struct ucontext));
  68
  69         if(restorer == NULL)
  70                 panic("setup_signal_stack_si - no restorer");
  71
  72         if(copy_to_user((void *) start, signal_frame_si.common.data,
  73                         signal_frame_si.common.len) ||
  74            copy_to_user((void *) (start + signal_frame_si.common.sig_index),
  75                         &sig, sizeof(sig)) ||
  76            copy_siginfo_to_user(sip, info) ||
  77            copy_to_user((void *) (start + signal_frame_si.sip_index), &sip,
  78                         sizeof(sip)) ||
  79            copy_ucontext_to_user(ucp, fp, mask, PT_REGS_SP(regs)) ||
  80            copy_to_user((void *) (start + signal_frame_si.ucp_index), &ucp,
  81                         sizeof(ucp)) ||
  82            copy_restorer(restorer, start, signal_frame_si.common.sr_index,
  83                          signal_frame_si.common.sr_relative))
  84                 return(1);
  85
  86         PT_REGS_IP(regs) = handler;
  87         PT_REGS_SP(regs) = start + signal_frame_si.common.sp_index;
  88         return(0);
  89 }
  90
  91 int setup_signal_stack_sc(unsigned long stack_top, int sig,
  92                           unsigned long handler, void (*restorer)(void),
  93                           struct pt_regs *regs, sigset_t *mask)
  94 {
  95         struct frame_common *frame = &signal_frame_sc_sr.common;
  96         void *user_sc;
  97         int sig_size = (_NSIG_WORDS - 1) * sizeof(unsigned long);
  98         unsigned long sigs, sr;
  99         unsigned long start = stack_top - frame->len - sig_size;
 100
 101         user_sc = (void *) (start + signal_frame_sc_sr.sc_index);
 102         if(restorer == NULL){
 103                 frame = &signal_frame_sc.common;
 104                 user_sc = (void *) (start + signal_frame_sc.sc_index);
 105                 sr = (unsigned long) frame->data;
 106                 sr += frame->sr_index;
 107                 sr = *((unsigned long *) sr);
 108                 restorer = ((void (*)(void)) sr);
 109         }
 110
 111         sigs = start + frame->len;
 112         if(copy_to_user((void *) start, frame->data, frame->len) ||
 113            copy_to_user((void *) (start + frame->sig_index), &sig,
 114                         sizeof(sig)) ||
 115            copy_sc_to_user(user_sc, NULL, regs,
 116                            &signal_frame_sc.common.arch) ||
 117            copy_to_user(sc_sigmask(user_sc), mask, sizeof(mask->sig[0])) ||
 118            copy_to_user((void *) sigs, &mask->sig[1], sig_size) ||
 119            copy_restorer(restorer, start, frame->sr_index, frame->sr_relative))
 120                 return(1);
 121
 122         PT_REGS_IP(regs) = handler;
 123         PT_REGS_SP(regs) = start + frame->sp_index;
 124
 125         return(0);
 126 }
 127
 128 /*
 129  * Overrides for Emacs so that we follow Linus's tabbing style.
 130  * Emacs will notice this stuff at the end of the file and automatically
 131  * adjust the settings for this buffer only.  This must remain at the end
 132  * of the file.
 133  * ---------------------------------------------------------------------------
 134  * Local variables:
 135  * c-file-style: "linux"
 136  * End:
 137  */