Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 1 | /* |
| 2 | * Signal support for Hexagon processor |
| 3 | * |
Richard Kuo | 7c6a5df | 2013-03-28 20:45:40 -0500 | [diff] [blame] | 4 | * Copyright (c) 2010-2012, The Linux Foundation. All rights reserved. |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License version 2 and |
| 8 | * only version 2 as published by the Free Software Foundation. |
| 9 | * |
| 10 | * This program is distributed in the hope that it will be useful, |
| 11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | * GNU General Public License for more details. |
| 14 | * |
| 15 | * You should have received a copy of the GNU General Public License |
| 16 | * along with this program; if not, write to the Free Software |
| 17 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 18 | * 02110-1301, USA. |
| 19 | */ |
| 20 | |
| 21 | #include <linux/linkage.h> |
| 22 | #include <linux/syscalls.h> |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 23 | #include <linux/tracehook.h> |
| 24 | #include <asm/registers.h> |
| 25 | #include <asm/thread_info.h> |
| 26 | #include <asm/unistd.h> |
| 27 | #include <asm/uaccess.h> |
| 28 | #include <asm/ucontext.h> |
| 29 | #include <asm/cacheflush.h> |
| 30 | #include <asm/signal.h> |
| 31 | #include <asm/vdso.h> |
| 32 | |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 33 | struct rt_sigframe { |
| 34 | unsigned long tramp[2]; |
| 35 | struct siginfo info; |
| 36 | struct ucontext uc; |
| 37 | }; |
| 38 | |
Richard Weinberger | 8bc77aa | 2014-03-05 15:24:06 +0100 | [diff] [blame] | 39 | static void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 40 | size_t frame_size) |
| 41 | { |
Richard Weinberger | 8bc77aa | 2014-03-05 15:24:06 +0100 | [diff] [blame] | 42 | unsigned long sp = sigsp(regs->r29, ksig); |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 43 | |
| 44 | return (void __user *)((sp - frame_size) & ~(sizeof(long long) - 1)); |
| 45 | } |
| 46 | |
| 47 | static int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) |
| 48 | { |
| 49 | unsigned long tmp; |
| 50 | int err = 0; |
| 51 | |
| 52 | err |= copy_to_user(&sc->sc_regs.r0, ®s->r00, |
| 53 | 32*sizeof(unsigned long)); |
| 54 | |
| 55 | err |= __put_user(regs->sa0, &sc->sc_regs.sa0); |
| 56 | err |= __put_user(regs->lc0, &sc->sc_regs.lc0); |
| 57 | err |= __put_user(regs->sa1, &sc->sc_regs.sa1); |
| 58 | err |= __put_user(regs->lc1, &sc->sc_regs.lc1); |
| 59 | err |= __put_user(regs->m0, &sc->sc_regs.m0); |
| 60 | err |= __put_user(regs->m1, &sc->sc_regs.m1); |
| 61 | err |= __put_user(regs->usr, &sc->sc_regs.usr); |
| 62 | err |= __put_user(regs->preds, &sc->sc_regs.p3_0); |
| 63 | err |= __put_user(regs->gp, &sc->sc_regs.gp); |
| 64 | err |= __put_user(regs->ugp, &sc->sc_regs.ugp); |
Richard Kuo | 60c4ba9 | 2012-03-27 17:38:09 -0500 | [diff] [blame] | 65 | #if CONFIG_HEXAGON_ARCH_VERSION >= 4 |
| 66 | err |= __put_user(regs->cs0, &sc->sc_regs.cs0); |
| 67 | err |= __put_user(regs->cs1, &sc->sc_regs.cs1); |
| 68 | #endif |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 69 | tmp = pt_elr(regs); err |= __put_user(tmp, &sc->sc_regs.pc); |
| 70 | tmp = pt_cause(regs); err |= __put_user(tmp, &sc->sc_regs.cause); |
| 71 | tmp = pt_badva(regs); err |= __put_user(tmp, &sc->sc_regs.badva); |
| 72 | |
| 73 | return err; |
| 74 | } |
| 75 | |
| 76 | static int restore_sigcontext(struct pt_regs *regs, |
| 77 | struct sigcontext __user *sc) |
| 78 | { |
| 79 | unsigned long tmp; |
| 80 | int err = 0; |
| 81 | |
| 82 | err |= copy_from_user(®s->r00, &sc->sc_regs.r0, |
| 83 | 32 * sizeof(unsigned long)); |
| 84 | |
| 85 | err |= __get_user(regs->sa0, &sc->sc_regs.sa0); |
| 86 | err |= __get_user(regs->lc0, &sc->sc_regs.lc0); |
| 87 | err |= __get_user(regs->sa1, &sc->sc_regs.sa1); |
| 88 | err |= __get_user(regs->lc1, &sc->sc_regs.lc1); |
| 89 | err |= __get_user(regs->m0, &sc->sc_regs.m0); |
| 90 | err |= __get_user(regs->m1, &sc->sc_regs.m1); |
| 91 | err |= __get_user(regs->usr, &sc->sc_regs.usr); |
| 92 | err |= __get_user(regs->preds, &sc->sc_regs.p3_0); |
| 93 | err |= __get_user(regs->gp, &sc->sc_regs.gp); |
| 94 | err |= __get_user(regs->ugp, &sc->sc_regs.ugp); |
Richard Kuo | 60c4ba9 | 2012-03-27 17:38:09 -0500 | [diff] [blame] | 95 | #if CONFIG_HEXAGON_ARCH_VERSION >= 4 |
| 96 | err |= __get_user(regs->cs0, &sc->sc_regs.cs0); |
| 97 | err |= __get_user(regs->cs1, &sc->sc_regs.cs1); |
| 98 | #endif |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 99 | err |= __get_user(tmp, &sc->sc_regs.pc); pt_set_elr(regs, tmp); |
| 100 | |
| 101 | return err; |
| 102 | } |
| 103 | |
| 104 | /* |
| 105 | * Setup signal stack frame with siginfo structure |
| 106 | */ |
Richard Weinberger | ac44362 | 2013-10-07 13:50:08 +0200 | [diff] [blame] | 107 | static int setup_rt_frame(struct ksignal *ksig, sigset_t *set, |
| 108 | struct pt_regs *regs) |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 109 | { |
| 110 | int err = 0; |
| 111 | struct rt_sigframe __user *frame; |
| 112 | struct hexagon_vdso *vdso = current->mm->context.vdso; |
| 113 | |
Richard Weinberger | 8bc77aa | 2014-03-05 15:24:06 +0100 | [diff] [blame] | 114 | frame = get_sigframe(ksig, regs, sizeof(struct rt_sigframe)); |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 115 | |
| 116 | if (!access_ok(VERIFY_WRITE, frame, sizeof(struct rt_sigframe))) |
Richard Weinberger | ac44362 | 2013-10-07 13:50:08 +0200 | [diff] [blame] | 117 | return -EFAULT; |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 118 | |
Richard Weinberger | ac44362 | 2013-10-07 13:50:08 +0200 | [diff] [blame] | 119 | if (copy_siginfo_to_user(&frame->info, &ksig->info)) |
| 120 | return -EFAULT; |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 121 | |
| 122 | /* The on-stack signal trampoline is no longer executed; |
| 123 | * however, the libgcc signal frame unwinding code checks for |
| 124 | * the presence of these two numeric magic values. |
| 125 | */ |
| 126 | err |= __put_user(0x7800d166, &frame->tramp[0]); |
| 127 | err |= __put_user(0x5400c004, &frame->tramp[1]); |
| 128 | err |= setup_sigcontext(regs, &frame->uc.uc_mcontext); |
| 129 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); |
Al Viro | da36f98 | 2012-12-23 02:46:34 -0500 | [diff] [blame] | 130 | err |= __save_altstack(&frame->uc.uc_stack, user_stack_pointer(regs)); |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 131 | if (err) |
Richard Weinberger | ac44362 | 2013-10-07 13:50:08 +0200 | [diff] [blame] | 132 | return -EFAULT; |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 133 | |
| 134 | /* Load r0/r1 pair with signumber/siginfo pointer... */ |
| 135 | regs->r0100 = ((unsigned long long)((unsigned long)&frame->info) << 32) |
Richard Weinberger | ac44362 | 2013-10-07 13:50:08 +0200 | [diff] [blame] | 136 | | (unsigned long long)ksig->sig; |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 137 | regs->r02 = (unsigned long) &frame->uc; |
| 138 | regs->r31 = (unsigned long) vdso->rt_signal_trampoline; |
| 139 | pt_psp(regs) = (unsigned long) frame; |
Richard Weinberger | ac44362 | 2013-10-07 13:50:08 +0200 | [diff] [blame] | 140 | pt_set_elr(regs, (unsigned long)ksig->ka.sa.sa_handler); |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 141 | |
| 142 | return 0; |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 143 | } |
| 144 | |
| 145 | /* |
| 146 | * Setup invocation of signal handler |
| 147 | */ |
Richard Weinberger | ac44362 | 2013-10-07 13:50:08 +0200 | [diff] [blame] | 148 | static void handle_signal(struct ksignal *ksig, struct pt_regs *regs) |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 149 | { |
Richard Weinberger | ac44362 | 2013-10-07 13:50:08 +0200 | [diff] [blame] | 150 | int ret; |
| 151 | |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 152 | /* |
| 153 | * If we're handling a signal that aborted a system call, |
| 154 | * set up the error return value before adding the signal |
| 155 | * frame to the stack. |
| 156 | */ |
| 157 | |
| 158 | if (regs->syscall_nr >= 0) { |
| 159 | switch (regs->r00) { |
| 160 | case -ERESTART_RESTARTBLOCK: |
| 161 | case -ERESTARTNOHAND: |
| 162 | regs->r00 = -EINTR; |
| 163 | break; |
| 164 | case -ERESTARTSYS: |
Richard Weinberger | ac44362 | 2013-10-07 13:50:08 +0200 | [diff] [blame] | 165 | if (!(ksig->ka.sa.sa_flags & SA_RESTART)) { |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 166 | regs->r00 = -EINTR; |
| 167 | break; |
| 168 | } |
| 169 | /* Fall through */ |
| 170 | case -ERESTARTNOINTR: |
| 171 | regs->r06 = regs->syscall_nr; |
| 172 | pt_set_elr(regs, pt_elr(regs) - 4); |
| 173 | regs->r00 = regs->restart_r0; |
| 174 | break; |
| 175 | default: |
| 176 | break; |
| 177 | } |
| 178 | } |
| 179 | |
| 180 | /* |
| 181 | * Set up the stack frame; not doing the SA_SIGINFO thing. We |
| 182 | * only set up the rt_frame flavor. |
| 183 | */ |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 184 | /* If there was an error on setup, no signal was delivered. */ |
Richard Weinberger | ac44362 | 2013-10-07 13:50:08 +0200 | [diff] [blame] | 185 | ret = setup_rt_frame(ksig, sigmask_to_save(), regs); |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 186 | |
Richard Weinberger | ac44362 | 2013-10-07 13:50:08 +0200 | [diff] [blame] | 187 | signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLESTEP)); |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 188 | } |
| 189 | |
| 190 | /* |
| 191 | * Called from return-from-event code. |
| 192 | */ |
Richard Kuo | a11e67c | 2012-05-29 17:23:14 -0500 | [diff] [blame] | 193 | void do_signal(struct pt_regs *regs) |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 194 | { |
Richard Weinberger | ac44362 | 2013-10-07 13:50:08 +0200 | [diff] [blame] | 195 | struct ksignal ksig; |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 196 | |
| 197 | if (!user_mode(regs)) |
| 198 | return; |
| 199 | |
Richard Weinberger | ac44362 | 2013-10-07 13:50:08 +0200 | [diff] [blame] | 200 | if (get_signal(&ksig)) { |
| 201 | handle_signal(&ksig, regs); |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 202 | return; |
| 203 | } |
| 204 | |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 205 | /* |
Richard Kuo | a11e67c | 2012-05-29 17:23:14 -0500 | [diff] [blame] | 206 | * No (more) signals; if we came from a system call, handle the restart. |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 207 | */ |
Richard Kuo | a11e67c | 2012-05-29 17:23:14 -0500 | [diff] [blame] | 208 | |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 209 | if (regs->syscall_nr >= 0) { |
| 210 | switch (regs->r00) { |
| 211 | case -ERESTARTNOHAND: |
| 212 | case -ERESTARTSYS: |
| 213 | case -ERESTARTNOINTR: |
| 214 | regs->r06 = regs->syscall_nr; |
| 215 | break; |
| 216 | case -ERESTART_RESTARTBLOCK: |
| 217 | regs->r06 = __NR_restart_syscall; |
| 218 | break; |
| 219 | default: |
| 220 | goto no_restart; |
| 221 | } |
| 222 | pt_set_elr(regs, pt_elr(regs) - 4); |
| 223 | regs->r00 = regs->restart_r0; |
| 224 | } |
| 225 | |
| 226 | no_restart: |
| 227 | /* If there's no signal to deliver, put the saved sigmask back */ |
Al Viro | 51a7b44 | 2012-05-21 23:33:55 -0400 | [diff] [blame] | 228 | restore_saved_sigmask(); |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 229 | } |
| 230 | |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 231 | /* |
| 232 | * Architecture-specific wrappers for signal-related system calls |
| 233 | */ |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 234 | |
| 235 | asmlinkage int sys_rt_sigreturn(void) |
| 236 | { |
Al Viro | 9952185 | 2012-10-18 22:45:24 -0400 | [diff] [blame] | 237 | struct pt_regs *regs = current_pt_regs(); |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 238 | struct rt_sigframe __user *frame; |
| 239 | sigset_t blocked; |
| 240 | |
Al Viro | ef9b122 | 2012-04-22 03:31:24 -0400 | [diff] [blame] | 241 | /* Always make any pending restarted system calls return -EINTR */ |
Andy Lutomirski | f56141e | 2015-02-12 15:01:14 -0800 | [diff] [blame] | 242 | current->restart_block.fn = do_no_restart_syscall; |
Al Viro | ef9b122 | 2012-04-22 03:31:24 -0400 | [diff] [blame] | 243 | |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 244 | frame = (struct rt_sigframe __user *)pt_psp(regs); |
| 245 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) |
| 246 | goto badframe; |
| 247 | if (__copy_from_user(&blocked, &frame->uc.uc_sigmask, sizeof(blocked))) |
| 248 | goto badframe; |
| 249 | |
Matt Fleming | 43aca32 | 2012-03-23 15:02:43 -0700 | [diff] [blame] | 250 | set_current_blocked(&blocked); |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 251 | |
| 252 | if (restore_sigcontext(regs, &frame->uc.uc_mcontext)) |
| 253 | goto badframe; |
| 254 | |
| 255 | /* Restore the user's stack as well */ |
| 256 | pt_psp(regs) = regs->r29; |
| 257 | |
Richard Kuo | a11e67c | 2012-05-29 17:23:14 -0500 | [diff] [blame] | 258 | regs->syscall_nr = -1; |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 259 | |
Al Viro | 1e974c2 | 2012-12-23 02:43:08 -0500 | [diff] [blame] | 260 | if (restore_altstack(&frame->uc.uc_stack)) |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 261 | goto badframe; |
| 262 | |
Richard Kuo | a11e67c | 2012-05-29 17:23:14 -0500 | [diff] [blame] | 263 | return regs->r00; |
Richard Kuo | cd5b61d | 2011-10-31 18:41:21 -0500 | [diff] [blame] | 264 | |
| 265 | badframe: |
| 266 | force_sig(SIGSEGV, current); |
| 267 | return 0; |
| 268 | } |