arch/um/sys-x86_64/signal.c

   1 /*
   2  * Copyright (C) 2003 PathScale, Inc.
   3  * Licensed under the GPL
   4  */
   5
   6 #include "linux/stddef.h"
   7 #include "linux/errno.h"
   8 #include "linux/personality.h"
   9 #include "linux/ptrace.h"
  10 #include "asm/current.h"
  11 #include "asm/uaccess.h"
  12 #include "asm/sigcontext.h"
  13 #include "asm/ptrace.h"
  14 #include "asm/arch/ucontext.h"
  15 #include "choose-mode.h"
  16 #include "sysdep/ptrace.h"
  17 #include "frame_kern.h"
  18
  19 #ifdef CONFIG_MODE_SKAS
  20
  21 #include "skas.h"
  22
  23 static int copy_sc_from_user_skas(struct pt_regs *regs,
  24                                  struct sigcontext *from)
  25 {
  26        int err = 0;
  27
  28 #define GETREG(regs, regno, sc, regname) \
  29        __get_user((regs)->regs.skas.regs[(regno) / sizeof(unsigned long)], \
  30                   &(sc)->regname)
  31
  32        err |= GETREG(regs, R8, from, r8);
  33        err |= GETREG(regs, R9, from, r9);
  34        err |= GETREG(regs, R10, from, r10);
  35        err |= GETREG(regs, R11, from, r11);
  36        err |= GETREG(regs, R12, from, r12);
  37        err |= GETREG(regs, R13, from, r13);
  38        err |= GETREG(regs, R14, from, r14);
  39        err |= GETREG(regs, R15, from, r15);
  40        err |= GETREG(regs, RDI, from, rdi);
  41        err |= GETREG(regs, RSI, from, rsi);
  42        err |= GETREG(regs, RBP, from, rbp);
  43        err |= GETREG(regs, RBX, from, rbx);
  44        err |= GETREG(regs, RDX, from, rdx);
  45        err |= GETREG(regs, RAX, from, rax);
  46        err |= GETREG(regs, RCX, from, rcx);
  47        err |= GETREG(regs, RSP, from, rsp);
  48        err |= GETREG(regs, RIP, from, rip);
  49        err |= GETREG(regs, EFLAGS, from, eflags);
  50        err |= GETREG(regs, CS, from, cs);
  51
  52 #undef GETREG
  53
  54        return(err);
  55 }
  56
  57 int copy_sc_to_user_skas(struct sigcontext *to, struct _fpstate *to_fp,
  58                         struct pt_regs *regs, unsigned long mask)
  59 {
  60         struct faultinfo * fi = &current->thread.arch.faultinfo;
  61         int err = 0;
  62
  63         err |= __put_user(0, &to->gs);
  64         err |= __put_user(0, &to->fs);
  65
  66 #define PUTREG(regs, regno, sc, regname) \
  67        __put_user((regs)->regs.skas.regs[(regno) / sizeof(unsigned long)], \
  68                   &(sc)->regname)
  69
  70         err |= PUTREG(regs, RDI, to, rdi);
  71         err |= PUTREG(regs, RSI, to, rsi);
  72         err |= PUTREG(regs, RBP, to, rbp);
  73         err |= PUTREG(regs, RSP, to, rsp);
  74         err |= PUTREG(regs, RBX, to, rbx);
  75         err |= PUTREG(regs, RDX, to, rdx);
  76         err |= PUTREG(regs, RCX, to, rcx);
  77         err |= PUTREG(regs, RAX, to, rax);
  78         err |= PUTREG(regs, R8, to, r8);
  79         err |= PUTREG(regs, R9, to, r9);
  80         err |= PUTREG(regs, R10, to, r10);
  81         err |= PUTREG(regs, R11, to, r11);
  82         err |= PUTREG(regs, R12, to, r12);
  83         err |= PUTREG(regs, R13, to, r13);
  84         err |= PUTREG(regs, R14, to, r14);
  85         err |= PUTREG(regs, R15, to, r15);
  86         err |= PUTREG(regs, CS, to, cs); /* XXX x86_64 doesn't do this */
  87
  88         err |= __put_user(fi->cr2, &to->cr2);
  89         err |= __put_user(fi->error_code, &to->err);
  90         err |= __put_user(fi->trap_no, &to->trapno);
  91
  92         err |= PUTREG(regs, RIP, to, rip);
  93         err |= PUTREG(regs, EFLAGS, to, eflags);
  94 #undef PUTREG
  95
  96         err |= __put_user(mask, &to->oldmask);
  97
  98         return(err);
  99 }
 100
 101 #endif
 102
 103 #ifdef CONFIG_MODE_TT
 104 int copy_sc_from_user_tt(struct sigcontext *to, struct sigcontext *from,
 105                         int fpsize)
 106 {
 107        struct _fpstate *to_fp, *from_fp;
 108        unsigned long sigs;
 109        int err;
 110
 111        to_fp = to->fpstate;
 112        from_fp = from->fpstate;
 113        sigs = to->oldmask;
 114        err = copy_from_user(to, from, sizeof(*to));
 115        to->oldmask = sigs;
 116        return(err);
 117 }
 118
 119 int copy_sc_to_user_tt(struct sigcontext *to, struct _fpstate *fp,
 120                       struct sigcontext *from, int fpsize)
 121 {
 122        struct _fpstate *to_fp, *from_fp;
 123        int err;
 124
 125        to_fp = (fp ? fp : (struct _fpstate *) (to + 1));
 126        from_fp = from->fpstate;
 127        err = copy_to_user(to, from, sizeof(*to));
 128        return(err);
 129 }
 130
 131 #endif
 132
 133 static int copy_sc_from_user(struct pt_regs *to, void __user *from)
 134 {
 135        int ret;
 136
 137        ret = CHOOSE_MODE(copy_sc_from_user_tt(UPT_SC(&to->regs), from,
 138                                               sizeof(struct _fpstate)),
 139                          copy_sc_from_user_skas(to, from));
 140        return(ret);
 141 }
 142
 143 static int copy_sc_to_user(struct sigcontext *to, struct _fpstate *fp,
 144                           struct pt_regs *from, unsigned long mask)
 145 {
 146        return(CHOOSE_MODE(copy_sc_to_user_tt(to, fp, UPT_SC(&from->regs),
 147                                              sizeof(*fp)),
 148                           copy_sc_to_user_skas(to, fp, from, mask)));
 149 }
 150
 151 struct rt_sigframe
 152 {
 153        char *pretcode;
 154        struct ucontext uc;
 155        struct siginfo info;
 156 };
 157
 158 #define round_down(m, n) (((m) / (n)) * (n))
 159
 160 int setup_signal_stack_si(unsigned long stack_top, int sig,
 161                           struct k_sigaction *ka, struct pt_regs * regs,
 162                           siginfo_t *info, sigset_t *set)
 163 {
 164         struct rt_sigframe __user *frame;
 165         struct _fpstate __user *fp = NULL;
 166         int err = 0;
 167         struct task_struct *me = current;
 168
 169         frame = (struct rt_sigframe __user *)
 170                 round_down(stack_top - sizeof(struct rt_sigframe), 16) - 8;
 171         frame = (struct rt_sigframe *) ((unsigned long) frame - 128);
 172
 173         if (!access_ok(VERIFY_WRITE, fp, sizeof(struct _fpstate)))
 174                 goto out;
 175
 176 #if 0 /* XXX */
 177         if (save_i387(fp) < 0)
 178                 err |= -1;
 179 #endif
 180         if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
 181                 goto out;
 182
 183         if (ka->sa.sa_flags & SA_SIGINFO) {
 184                 err |= copy_siginfo_to_user(&frame->info, info);
 185                 if (err)
 186                         goto out;
 187         }
 188
 189         /* Create the ucontext.  */
 190         err |= __put_user(0, &frame->uc.uc_flags);
 191         err |= __put_user(0, &frame->uc.uc_link);
 192         err |= __put_user(me->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
 193         err |= __put_user(sas_ss_flags(PT_REGS_SP(regs)),
 194                           &frame->uc.uc_stack.ss_flags);
 195         err |= __put_user(me->sas_ss_size, &frame->uc.uc_stack.ss_size);
 196         err |= copy_sc_to_user(&frame->uc.uc_mcontext, fp, regs, set->sig[0]);
 197         err |= __put_user(fp, &frame->uc.uc_mcontext.fpstate);
 198         if (sizeof(*set) == 16) {
 199                 __put_user(set->sig[0], &frame->uc.uc_sigmask.sig[0]);
 200                 __put_user(set->sig[1], &frame->uc.uc_sigmask.sig[1]);
 201         }
 202         else
 203                 err |= __copy_to_user(&frame->uc.uc_sigmask, set,
 204                                       sizeof(*set));
 205
 206         /* Set up to return from userspace.  If provided, use a stub
 207            already in userspace.  */
 208         /* x86-64 should always use SA_RESTORER. */
 209         if (ka->sa.sa_flags & SA_RESTORER)
 210                 err |= __put_user(ka->sa.sa_restorer, &frame->pretcode);
 211         else
 212                 /* could use a vstub here */
 213                 goto out;
 214
 215         if (err)
 216                 goto out;
 217
 218         /* Set up registers for signal handler */
 219         {
 220                 struct exec_domain *ed = current_thread_info()->exec_domain;
 221                 if (unlikely(ed && ed->signal_invmap && sig < 32))
 222                         sig = ed->signal_invmap[sig];
 223         }
 224
 225         PT_REGS_RDI(regs) = sig;
 226         /* In case the signal handler was declared without prototypes */
 227         PT_REGS_RAX(regs) = 0;
 228
 229         /* This also works for non SA_SIGINFO handlers because they expect the
 230            next argument after the signal number on the stack. */
 231         PT_REGS_RSI(regs) = (unsigned long) &frame->info;
 232         PT_REGS_RDX(regs) = (unsigned long) &frame->uc;
 233         PT_REGS_RIP(regs) = (unsigned long) ka->sa.sa_handler;
 234
 235         PT_REGS_RSP(regs) = (unsigned long) frame;
 236  out:
 237         return(err);
 238 }
 239
 240 long sys_rt_sigreturn(struct pt_regs *regs)
 241 {
 242         unsigned long sp = PT_REGS_SP(&current->thread.regs);
 243         struct rt_sigframe __user *frame =
 244                 (struct rt_sigframe __user *)(sp - 8);
 245         struct ucontext __user *uc = &frame->uc;
 246         sigset_t set;
 247
 248         if(copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
 249                 goto segfault;
 250
 251         sigdelsetmask(&set, ~_BLOCKABLE);
 252
 253         spin_lock_irq(&current->sighand->siglock);
 254         current->blocked = set;
 255         recalc_sigpending();
 256         spin_unlock_irq(&current->sighand->siglock);
 257
 258         if(copy_sc_from_user(&current->thread.regs, &uc->uc_mcontext))
 259                 goto segfault;
 260
 261         /* Avoid ERESTART handling */
 262         PT_REGS_SYSCALL_NR(&current->thread.regs) = -1;
 263         return(PT_REGS_SYSCALL_RET(&current->thread.regs));
 264
 265  segfault:
 266         force_sig(SIGSEGV, current);
 267         return 0;
 268 }
 269 /*
 270  * Overrides for Emacs so that we follow Linus's tabbing style.
 271  * Emacs will notice this stuff at the end of the file and automatically
 272  * adjust the settings for this buffer only.  This must remain at the end
 273  * of the file.
 274  * ---------------------------------------------------------------------------
 275  * Local variables:
 276  * c-file-style: "linux"
 277  * End:
 278  */