summaryrefslogtreecommitdiffstats
path: root/arch
diff options
context:
space:
mode:
authorChris Zankel <chris@zankel.net>2007-05-31 17:49:32 -0700
committerChris Zankel <chris@zankel.net>2007-05-31 17:49:32 -0700
commit29c4dfd92edc26c2cd2c0c64c9201d5b91d6418e (patch)
tree64b2884bb49a86f2895d9206b79bf9f64e384615 /arch
parentadba09f01577ea441a761a85aacb1e43b58d35c4 (diff)
downloadop-kernel-dev-29c4dfd92edc26c2cd2c0c64c9201d5b91d6418e.zip
op-kernel-dev-29c4dfd92edc26c2cd2c0c64c9201d5b91d6418e.tar.gz
[XTENSA] Remove non-rt signal handling
The non-rt signal handling was never really used, so we don't break anything. This patch also cleans up the signal stack-frame to make it independent from the processor configuration. It also improves the method used for controlling single-stepping. We now save and restore the 'icountlevel' register that controls single stepping and set or clear the saved state to enable or disable it. Signed-off-by: Chris Zankel <chris@zankel.net>
Diffstat (limited to 'arch')
-rw-r--r--arch/xtensa/kernel/asm-offsets.c1
-rw-r--r--arch/xtensa/kernel/entry.S36
-rw-r--r--arch/xtensa/kernel/signal.c795
3 files changed, 334 insertions, 498 deletions
diff --git a/arch/xtensa/kernel/asm-offsets.c b/arch/xtensa/kernel/asm-offsets.c
index 698079b..d0323cd 100644
--- a/arch/xtensa/kernel/asm-offsets.c
+++ b/arch/xtensa/kernel/asm-offsets.c
@@ -39,6 +39,7 @@ int main(void)
DEFINE(PT_LEND, offsetof (struct pt_regs, lend));
DEFINE(PT_LCOUNT, offsetof (struct pt_regs, lcount));
DEFINE(PT_SAR, offsetof (struct pt_regs, sar));
+ DEFINE(PT_ICOUNTLEVEL, offsetof (struct pt_regs, icountlevel));
DEFINE(PT_SYSCALL, offsetof (struct pt_regs, syscall));
DEFINE(PT_AREG, offsetof (struct pt_regs, areg[0]));
DEFINE(PT_AREG0, offsetof (struct pt_regs, areg[0]));
diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S
index 9e271ba..8dc7a2c 100644
--- a/arch/xtensa/kernel/entry.S
+++ b/arch/xtensa/kernel/entry.S
@@ -125,8 +125,9 @@ _user_exception:
movi a2, 0
rsr a3, SAR
- wsr a2, ICOUNTLEVEL
+ xsr a2, ICOUNTLEVEL
s32i a3, a1, PT_SAR
+ s32i a2, a1, PT_ICOUNTLEVEL
/* Rotate ws so that the current windowbase is at bit0. */
/* Assume ws = xxwww1yyyy. Rotate ws right, so that a2 = yyyyxxwww1 */
@@ -276,8 +277,9 @@ _kernel_exception:
movi a2, 0
rsr a3, SAR
- wsr a2, ICOUNTLEVEL
+ xsr a2, ICOUNTLEVEL
s32i a3, a1, PT_SAR
+ s32i a2, a1, PT_ICOUNTLEVEL
/* Rotate ws so that the current windowbase is at bit0. */
/* Assume ws = xxwww1yyyy. Rotate ws right, so that a2 = yyyyxxwww1 */
@@ -330,14 +332,16 @@ _kernel_exception:
common_exception:
- /* Save EXCVADDR, DEBUGCAUSE, and PC, and clear LCOUNT */
+ /* Save some registers, disable loops and clear the syscall flag. */
rsr a2, DEBUGCAUSE
rsr a3, EPC_1
s32i a2, a1, PT_DEBUGCAUSE
s32i a3, a1, PT_PC
+ movi a2, -1
rsr a3, EXCVADDR
+ s32i a2, a1, PT_SYSCALL
movi a2, 0
s32i a3, a1, PT_EXCVADDR
xsr a2, LCOUNT
@@ -450,27 +454,8 @@ common_exception_return:
/* Restore the state of the task and return from the exception. */
-
- /* If we are returning from a user exception, and the process
- * to run next has PT_SINGLESTEP set, we want to setup
- * ICOUNT and ICOUNTLEVEL to step one instruction.
- * PT_SINGLESTEP is set by sys_ptrace (ptrace.c)
- */
-
4: /* a2 holds GET_CURRENT(a2,a1) */
- l32i a3, a2, TI_TASK
- l32i a3, a3, TASK_PTRACE
- bbci.l a3, PT_SINGLESTEP_BIT, 1f # jump if single-step flag is not set
-
- movi a3, -2 # PT_SINGLESTEP flag is set,
- movi a4, 1 # icountlevel of 1 means it won't
- wsr a3, ICOUNT # start counting until after rfe
- wsr a4, ICOUNTLEVEL # so setup icount & icountlevel.
- isync
-
-1:
-
#if XCHAL_EXTRA_SA_SIZE
/* For user exceptions, restore the extra state from the user's TCB. */
@@ -665,6 +650,13 @@ common_exception_exit:
wsr a3, LEND
wsr a2, LCOUNT
+ /* We control single stepping through the ICOUNTLEVEL register. */
+
+ l32i a2, a1, PT_ICOUNTLEVEL
+ movi a3, -2
+ wsr a2, ICOUNTLEVEL
+ wsr a3, ICOUNT
+
/* Check if it was double exception. */
l32i a0, a1, PT_DEPC
diff --git a/arch/xtensa/kernel/signal.c b/arch/xtensa/kernel/signal.c
index 5810767..033aae0 100644
--- a/arch/xtensa/kernel/signal.c
+++ b/arch/xtensa/kernel/signal.c
@@ -1,397 +1,239 @@
-// TODO coprocessor stuff
/*
- * linux/arch/xtensa/kernel/signal.c
+ * arch/xtensa/kernel/signal.c
*
- * Copyright (C) 1991, 1992 Linus Torvalds
- * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
- *
- * Joe Taylor <joe@tensilica.com>
- * Chris Zankel <chris@zankel.net>
+ * Default platform functions.
*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
*
+ * Copyright (C) 2005, 2006 Tensilica Inc.
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
*
+ * Chris Zankel <chris@zankel.net>
+ * Joe Taylor <joe@tensilica.com>
*/
-#include <asm/variant/core.h>
-#include <asm/coprocessor.h>
-#include <linux/sched.h>
-#include <linux/mm.h>
-#include <linux/smp.h>
-#include <linux/kernel.h>
#include <linux/signal.h>
#include <linux/errno.h>
-#include <linux/wait.h>
#include <linux/ptrace.h>
-#include <linux/unistd.h>
-#include <linux/stddef.h>
#include <linux/personality.h>
+#include <linux/freezer.h>
+
#include <asm/ucontext.h>
#include <asm/uaccess.h>
-#include <asm/pgtable.h>
#include <asm/cacheflush.h>
+#include <asm/coprocessor.h>
+#include <asm/unistd.h>
#define DEBUG_SIG 0
#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
-asmlinkage long sys_wait4(pid_t pid,unsigned int * stat_addr, int options,
- struct rusage * ru);
asmlinkage int do_signal(struct pt_regs *regs, sigset_t *oldset);
extern struct task_struct *coproc_owners[];
+extern void release_all_cp (struct task_struct *);
-/*
- * Atomically swap in the new signal mask, and wait for a signal.
+struct rt_sigframe
+{
+ struct siginfo info;
+ struct ucontext uc;
+ cp_state_t cpstate;
+ unsigned char retcode[6];
+ unsigned int window[4];
+};
+
+/*
+ * Flush register windows stored in pt_regs to stack.
+ * Returns 1 for errors.
+ *
+ * Note that windowbase, windowstart, and wmask are not updated!
*/
-int xtensa_sigsuspend(struct pt_regs *regs)
+int
+flush_window_regs_user(struct pt_regs *regs)
{
- old_sigset_t mask = (old_sigset_t) regs->areg[3];
- sigset_t saveset;
+ const unsigned long ws = regs->windowstart;
+ const unsigned long wb = regs->windowbase;
+ unsigned long sp = 0;
+ unsigned long wm;
+ int err = 1;
+ int base;
- mask &= _BLOCKABLE;
- spin_lock_irq(&current->sighand->siglock);
- saveset = current->blocked;
- siginitset(&current->blocked, mask);
- recalc_sigpending();
- spin_unlock_irq(&current->sighand->siglock);
+ /* Return if no other frames. */
- regs->areg[2] = -EINTR;
- while (1) {
- current->state = TASK_INTERRUPTIBLE;
- schedule();
- if (do_signal(regs, &saveset))
- return -EINTR;
- }
-}
+ if (regs->wmask == 1)
+ return 0;
-asmlinkage int
-xtensa_rt_sigsuspend(struct pt_regs *regs)
-{
- sigset_t *unewset = (sigset_t *) regs->areg[4];
- size_t sigsetsize = (size_t) regs->areg[3];
- sigset_t saveset, newset;
- /* XXX: Don't preclude handling different sized sigset_t's. */
- if (sigsetsize != sizeof(sigset_t))
- return -EINVAL;
+ /* Rotate windowmask and skip empty frames. */
- if (copy_from_user(&newset, unewset, sizeof(newset)))
- return -EFAULT;
- sigdelsetmask(&newset, ~_BLOCKABLE);
- spin_lock_irq(&current->sighand->siglock);
- saveset = current->blocked;
- current->blocked = newset;
- recalc_sigpending();
- spin_unlock_irq(&current->sighand->siglock);
+ wm = (ws >> wb) | (ws << (XCHAL_NUM_AREGS / 4 - wb));
+ base = (XCHAL_NUM_AREGS / 4) - (regs->wmask >> 4);
+
+ /* For call8 or call12 frames, we need the previous stack pointer. */
- regs->areg[2] = -EINTR;
- while (1) {
- current->state = TASK_INTERRUPTIBLE;
- schedule();
- if (do_signal(regs, &saveset))
- return -EINTR;
- }
-}
+ if ((regs->wmask & 2) == 0)
+ if (__get_user(sp, (int*)(regs->areg[base * 4 + 1] - 12)))
+ goto errout;
-asmlinkage int
-xtensa_sigaction(int sig, const struct old_sigaction *act,
- struct old_sigaction *oact)
-{
- struct k_sigaction new_ka, old_ka;
- int ret;
+ /* Spill frames to stack. */
- if (act) {
- old_sigset_t mask;
- if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
- __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
- __get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
- return -EFAULT;
- __get_user(new_ka.sa.sa_flags, &act->sa_flags);
- __get_user(mask, &act->sa_mask);
- siginitset(&new_ka.sa.sa_mask, mask);
- }
+ while (base < XCHAL_NUM_AREGS / 4) {
- ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
+ int m = (wm >> base);
+ int inc = 0;
- if (!ret && oact) {
- if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
- __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
- __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
- return -EFAULT;
- __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
- __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
- }
+ /* Save registers a4..a7 (call8) or a4...a11 (call12) */
- return ret;
-}
+ if (m & 2) { /* call4 */
+ inc = 1;
-asmlinkage int
-xtensa_sigaltstack(struct pt_regs *regs)
-{
- const stack_t *uss = (stack_t *) regs->areg[4];
- stack_t *uoss = (stack_t *) regs->areg[3];
+ } else if (m & 4) { /* call8 */
+ if (copy_to_user((void*)(sp - 32),
+ &regs->areg[(base + 1) * 4], 16))
+ goto errout;
+ inc = 2;
- if (regs->depc > 64)
- panic ("Double exception sys_sigreturn\n");
+ } else if (m & 8) { /* call12 */
+ if (copy_to_user((void*)(sp - 48),
+ &regs->areg[(base + 1) * 4], 32))
+ goto errout;
+ inc = 3;
+ }
+ /* Save current frame a0..a3 under next SP */
- return do_sigaltstack(uss, uoss, regs->areg[1]);
-}
+ sp = regs->areg[((base + inc) * 4 + 1) % XCHAL_NUM_AREGS];
+ if (copy_to_user((void*)(sp - 16), &regs->areg[base * 4], 16))
+ goto errout;
+
+ /* Get current stack pointer for next loop iteration. */
+
+ sp = regs->areg[base * 4 + 1];
+ base += inc;
+ }
+
+ return 0;
+errout:
+ return err;
+}
/*
- * Do a signal return; undo the signal stack.
+ * Note: We don't copy double exception 'regs', we have to finish double exc.
+ * first before we return to signal handler! This dbl.exc.handler might cause
+ * another double exception, but I think we are fine as the situation is the
+ * same as if we had returned to the signal handerl and got an interrupt
+ * immediately...
*/
-struct sigframe
-{
- struct sigcontext sc;
- struct _cpstate cpstate;
- unsigned long extramask[_NSIG_WORDS-1];
- unsigned char retcode[6];
- unsigned int reserved[4]; /* Reserved area for chaining */
- unsigned int window[4]; /* Window of 4 registers for initial context */
-};
-
-struct rt_sigframe
+static int
+setup_sigcontext(struct sigcontext __user *sc, cp_state_t *cpstate,
+ struct pt_regs *regs, unsigned long mask)
{
- struct siginfo info;
- struct ucontext uc;
- struct _cpstate cpstate;
- unsigned char retcode[6];
- unsigned int reserved[4]; /* Reserved area for chaining */
- unsigned int window[4]; /* Window of 4 registers for initial context */
-};
+ int err = 0;
-extern void release_all_cp (struct task_struct *);
+#define COPY(x) err |= __put_user(regs->x, &sc->sc_##x)
+ COPY(pc);
+ COPY(ps);
+ COPY(lbeg);
+ COPY(lend);
+ COPY(lcount);
+ COPY(sar);
+#undef COPY
+ err |= flush_window_regs_user(regs);
+ err |= __copy_to_user (sc->sc_a, regs->areg, 16 * 4);
-// FIXME restore_cpextra
-static inline int
-restore_cpextra (struct _cpstate *buf)
-{
-#if 0
- /* The signal handler may have used coprocessors in which
- * case they are still enabled. We disable them to force a
- * reloading of the original task's CP state by the lazy
- * context-switching mechanisms of CP exception handling.
- * Also, we essentially discard any coprocessor state that the
- * signal handler created. */
+ // err |= __copy_to_user (sc->sc_a, regs->areg, XCHAL_NUM_AREGS * 4)
- struct task_struct *tsk = current;
- release_all_cp(tsk);
- return __copy_from_user(tsk->thread.cpextra, buf, XTENSA_CP_EXTRA_SIZE);
+#if XCHAL_HAVE_CP
+# error Coprocessors unsupported
+ err |= save_cpextra(cpstate);
+ err |= __put_user(err ? NULL : cpstate, &sc->sc_cpstate);
#endif
- return 0;
-}
-
-/* Note: We don't copy double exception 'tregs', we have to finish double exc. first before we return to signal handler! This dbl.exc.handler might cause another double exception, but I think we are fine as the situation is the same as if we had returned to the signal handerl and got an interrupt immediately...
- */
+ /* non-iBCS2 extensions.. */
+ err |= __put_user(mask, &sc->oldmask);
+ return err;
+}
static int
-restore_sigcontext(struct pt_regs *regs, struct sigcontext *sc)
+restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
{
- struct thread_struct *thread;
unsigned int err = 0;
unsigned long ps;
- struct _cpstate *buf;
#define COPY(x) err |= __get_user(regs->x, &sc->sc_##x)
COPY(pc);
- COPY(depc);
- COPY(wmask);
COPY(lbeg);
COPY(lend);
COPY(lcount);
COPY(sar);
- COPY(windowbase);
- COPY(windowstart);
#undef COPY
+ /* All registers were flushed to stack. Start with a prestine frame. */
+
+ regs->wmask = 1;
+ regs->windowbase = 0;
+ regs->windowstart = 1;
+
/* For PS, restore only PS.CALLINC.
* Assume that all other bits are either the same as for the signal
* handler, or the user mode value doesn't matter (e.g. PS.OWB).
*/
err |= __get_user(ps, &sc->sc_ps);
- regs->ps = (regs->ps & ~PS_CALLINC_MASK)
- | (ps & PS_CALLINC_MASK);
+ regs->ps = (regs->ps & ~PS_CALLINC_MASK) | (ps & PS_CALLINC_MASK);
/* Additional corruption checks */
- if ((regs->windowbase >= (XCHAL_NUM_AREGS/4))
- || ((regs->windowstart & ~((1<<(XCHAL_NUM_AREGS/4)) - 1)) != 0) )
- err = 1;
if ((regs->lcount > 0)
- && ((regs->lbeg > TASK_SIZE) || (regs->lend > TASK_SIZE)) )
+ && ((regs->lbeg > TASK_SIZE) || (regs->lend > TASK_SIZE)) )
err = 1;
- /* Restore extended register state.
- * See struct thread_struct in processor.h.
- */
- thread = &current->thread;
-
- err |= __copy_from_user (regs->areg, sc->sc_areg, XCHAL_NUM_AREGS*4);
- err |= __get_user(buf, &sc->sc_cpstate);
- if (buf) {
- if (!access_ok(VERIFY_READ, buf, sizeof(*buf)))
- goto badframe;
- err |= restore_cpextra(buf);
- }
-
- regs->syscall = -1; /* disable syscall checks */
- return err;
-
-badframe:
- return 1;
-}
-
-static inline void
-flush_my_cpstate(struct task_struct *tsk)
-{
- unsigned long flags;
- local_irq_save(flags);
-
-#if 0 // FIXME
- for (i = 0; i < XCHAL_CP_NUM; i++) {
- if (tsk == coproc_owners[i]) {
- xthal_validate_cp(i);
- xthal_save_cpregs(tsk->thread.cpregs_ptr[i], i);
+ err |= __copy_from_user(regs->areg, sc->sc_a, 16 * 4);
- /* Invalidate and "disown" the cp to allow
- * callers the chance to reset cp state in the
- * task_struct. */
+#if XCHAL_HAVE_CP
+# error Coprocessors unsupported
+ /* The signal handler may have used coprocessors in which
+ * case they are still enabled. We disable them to force a
+ * reloading of the original task's CP state by the lazy
+ * context-switching mechanisms of CP exception handling.
+ * Also, we essentially discard any coprocessor state that the
+ * signal handler created. */
- xthal_invalidate_cp(i);
- coproc_owners[i] = 0;
- }
+ if (!err) {
+ struct task_struct *tsk = current;
+ release_all_cp(tsk);
+ err |= __copy_from_user(tsk->thread.cpextra, sc->sc_cpstate,
+ XTENSA_CP_EXTRA_SIZE);
}
#endif
- local_irq_restore(flags);
-}
-
-/* Return codes:
- 0: nothing saved
- 1: stuff to save, successful
- -1: stuff to save, error happened
-*/
-static int
-save_cpextra (struct _cpstate *buf)
-{
-#if XCHAL_CP_NUM == 0
- return 0;
-#else
-
- /* FIXME: If a task has never used a coprocessor, there is
- * no need to save and restore anything. Tracking this
- * information would allow us to optimize this section.
- * Perhaps we can use current->used_math or (current->flags &
- * PF_USEDFPU) or define a new field in the thread
- * structure. */
-
- /* We flush any live, task-owned cp state to the task_struct,
- * then copy it all to the sigframe. Then we clear all
- * cp/extra state in the task_struct, effectively
- * clearing/resetting all cp/extra state for the signal
- * handler (cp-exception handling will load these new values
- * into the cp/extra registers.) This step is important for
- * things like a floating-point cp, where the OS must reset
- * the FCR to the default rounding mode. */
-
- int err = 0;
- struct task_struct *tsk = current;
-
- flush_my_cpstate(tsk);
- /* Note that we just copy everything: 'extra' and 'cp' state together.*/
- err |= __copy_to_user(buf, tsk->thread.cp_save, XTENSA_CP_EXTRA_SIZE);
- memset(tsk->thread.cp_save, 0, XTENSA_CP_EXTRA_SIZE);
-
-#if (XTENSA_CP_EXTRA_SIZE == 0)
-#error Sanity check on memset above, cpextra_size should not be zero.
-#endif
-
- return err ? -1 : 1;
-#endif
-}
-
-static int
-setup_sigcontext(struct sigcontext *sc, struct _cpstate *cpstate,
- struct pt_regs *regs, unsigned long mask)
-{
- struct thread_struct *thread;
- int err = 0;
-
-//printk("setup_sigcontext\n");
-#define COPY(x) err |= __put_user(regs->x, &sc->sc_##x)
- COPY(pc);
- COPY(ps);
- COPY(depc);
- COPY(wmask);
- COPY(lbeg);
- COPY(lend);
- COPY(lcount);
- COPY(sar);
- COPY(windowbase);
- COPY(windowstart);
-#undef COPY
-
- /* Save extended register state.
- * See struct thread_struct in processor.h.
- */
- thread = &current->thread;
- err |= __copy_to_user (sc->sc_areg, regs->areg, XCHAL_NUM_AREGS * 4);
- err |= save_cpextra(cpstate);
- err |= __put_user(err ? NULL : cpstate, &sc->sc_cpstate);
- /* non-iBCS2 extensions.. */
- err |= __put_user(mask, &sc->oldmask);
+ regs->syscall = -1; /* disable syscall checks */
return err;
}
-asmlinkage int xtensa_sigreturn(struct pt_regs *regs)
-{
- struct sigframe *frame = (struct sigframe *)regs->areg[1];
- sigset_t set;
- if (regs->depc > 64)
- panic ("Double exception sys_sigreturn\n");
-
- if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
- goto badframe;
-
- if (__get_user(set.sig[0], &frame->sc.oldmask)
- || (_NSIG_WORDS > 1
- && __copy_from_user(&set.sig[1], &frame->extramask,
- sizeof(frame->extramask))))
- goto badframe;
-
- sigdelsetmask(&set, ~_BLOCKABLE);
-
- spin_lock_irq(&current->sighand->siglock);
- current->blocked = set;
- recalc_sigpending();
- spin_unlock_irq(&current->sighand->siglock);
- if (restore_sigcontext(regs, &frame->sc))
- goto badframe;
- return regs->areg[2];
-badframe:
- force_sig(SIGSEGV, current);
- return 0;
-}
+/*
+ * Do a signal return; undo the signal stack.
+ */
-asmlinkage int xtensa_rt_sigreturn(struct pt_regs *regs)
+asmlinkage long xtensa_rt_sigreturn(long a0, long a1, long a2, long a3,
+ long a4, long a5, struct pt_regs *regs)
{
- struct rt_sigframe *frame = (struct rt_sigframe *)regs->areg[1];
+ struct rt_sigframe __user *frame;
sigset_t set;
- stack_t st;
int ret;
+
if (regs->depc > 64)
- {
- printk("!!!!!!! DEPC !!!!!!!\n");
- return 0;
- }
+ panic("rt_sigreturn in double exception!\n");
+
+ frame = (struct rt_sigframe __user *) regs->areg[1];
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
goto badframe;
@@ -407,13 +249,11 @@ asmlinkage int xtensa_rt_sigreturn(struct pt_regs *regs)
if (restore_sigcontext(regs, &frame->uc.uc_mcontext))
goto badframe;
+
ret = regs->areg[2];
- if (__copy_from_user(&st, &frame->uc.uc_stack, sizeof(st)))
+ if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->areg[1]) == -EFAULT)
goto badframe;
- /* It is more difficult to avoid calling this function than to
- call it and ignore errors. */
- do_sigaltstack(&st, NULL, regs->areg[1]);
return ret;
@@ -422,77 +262,50 @@ badframe:
return 0;
}
-/*
- * Set up a signal frame.
- */
+
/*
- * Determine which stack to use..
+ * Set up a signal frame.
*/
-static inline void *
-get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
-{
- if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! sas_ss_flags(sp))
- sp = current->sas_ss_sp + current->sas_ss_size;
-
- return (void *)((sp - frame_size) & -16ul);
-}
-
-#define USE_SIGRETURN 0
-#define USE_RT_SIGRETURN 1
static int
-gen_return_code(unsigned char *codemem, unsigned int use_rt_sigreturn)
+gen_return_code(unsigned char *codemem)
{
- unsigned int retcall;
int err = 0;
-#if 0
- /* Ignoring SA_RESTORER for now; it's supposed to be obsolete,
- * and the xtensa glibc doesn't use it.
+ /*
+ * The 12-bit immediate is really split up within the 24-bit MOVI
+ * instruction. As long as the above system call numbers fit within
+ * 8-bits, the following code works fine. See the Xtensa ISA for
+ * details.
*/
- if (ka->sa.sa_flags & SA_RESTORER) {
- regs->pr = (unsigned long) ka->sa.sa_restorer;
- } else
-#endif /* 0 */
- {
-
-#if (__NR_sigreturn > 255) || (__NR_rt_sigreturn > 255)
-
-/* The 12-bit immediate is really split up within the 24-bit MOVI
- * instruction. As long as the above system call numbers fit within
- * 8-bits, the following code works fine. See the Xtensa ISA for
- * details.
- */
-#error Generating the MOVI instruction below breaks!
+#if __NR_rt_sigreturn > 255
+# error Generating the MOVI instruction below breaks!
#endif
- retcall = use_rt_sigreturn ? __NR_rt_sigreturn : __NR_sigreturn;
-
#ifdef __XTENSA_EB__ /* Big Endian version */
- /* Generate instruction: MOVI a2, retcall */
- err |= __put_user(0x22, &codemem[0]);
- err |= __put_user(0x0a, &codemem[1]);
- err |= __put_user(retcall, &codemem[2]);
- /* Generate instruction: SYSCALL */
- err |= __put_user(0x00, &codemem[3]);
- err |= __put_user(0x05, &codemem[4]);
- err |= __put_user(0x00, &codemem[5]);
+ /* Generate instruction: MOVI a2, __NR_rt_sigreturn */
+ err |= __put_user(0x22, &codemem[0]);
+ err |= __put_user(0x0a, &codemem[1]);
+ err |= __put_user(__NR_rt_sigreturn, &codemem[2]);
+ /* Generate instruction: SYSCALL */
+ err |= __put_user(0x00, &codemem[3]);
+ err |= __put_user(0x05, &codemem[4]);
+ err |= __put_user(0x00, &codemem[5]);
#elif defined __XTENSA_EL__ /* Little Endian version */
- /* Generate instruction: MOVI a2, retcall */
- err |= __put_user(0x22, &codemem[0]);
- err |= __put_user(0xa0, &codemem[1]);
- err |= __put_user(retcall, &codemem[2]);
- /* Generate instruction: SYSCALL */
- err |= __put_user(0x00, &codemem[3]);
- err |= __put_user(0x50, &codemem[4]);
- err |= __put_user(0x00, &codemem[5]);
+ /* Generate instruction: MOVI a2, __NR_rt_sigreturn */
+ err |= __put_user(0x22, &codemem[0]);
+ err |= __put_user(0xa0, &codemem[1]);
+ err |= __put_user(__NR_rt_sigreturn, &codemem[2]);
+ /* Generate instruction: SYSCALL */
+ err |= __put_user(0x00, &codemem[3]);
+ err |= __put_user(0x50, &codemem[4]);
+ err |= __put_user(0x00, &codemem[5]);
#else
-#error Must use compiler for Xtensa processors.
+# error Must use compiler for Xtensa processors.
#endif
- }
/* Flush generated code out of the data cache */
@@ -504,97 +317,29 @@ gen_return_code(unsigned char *codemem, unsigned int use_rt_sigreturn)
return err;
}
-static void
-set_thread_state(struct pt_regs *regs, void *stack, unsigned char *retaddr,
- void *handler, unsigned long arg1, void *arg2, void *arg3)
-{
- /* Set up registers for signal handler */
- start_thread(regs, (unsigned long) handler, (unsigned long) stack);
-
- /* Set up a stack frame for a call4
- * Note: PS.CALLINC is set to one by start_thread
- */
- regs->areg[4] = (((unsigned long) retaddr) & 0x3fffffff) | 0x40000000;
- regs->areg[6] = arg1;
- regs->areg[7] = (unsigned long) arg2;
- regs->areg[8] = (unsigned long) arg3;
-}
-static void setup_frame(int sig, struct k_sigaction *ka,
+static void setup_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
sigset_t *set, struct pt_regs *regs)
{
- struct sigframe *frame;
+ struct rt_sigframe *frame;
int err = 0;
int signal;
+ unsigned long sp, ra;
- frame = get_sigframe(ka, regs->areg[1], sizeof(*frame));
- if (regs->depc > 64)
- {
- printk("!!!!!!! DEPC !!!!!!!\n");
- return;
- }
-
-
- if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
- goto give_sigsegv;
-
- signal = current_thread_info()->exec_domain
- && current_thread_info()->exec_domain->signal_invmap
- && sig < 32
- ? current_thread_info()->exec_domain->signal_invmap[sig]
- : sig;
-
- err |= setup_sigcontext(&frame->sc, &frame->cpstate, regs, set->sig[0]);
+ sp = regs->areg[1];
- if (_NSIG_WORDS > 1) {
- err |= __copy_to_user(frame->extramask, &set->sig[1],
- sizeof(frame->extramask));
+ if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! on_sig_stack(sp)) {
+ sp = current->sas_ss_sp + current->sas_ss_size;
}
- /* Create sys_sigreturn syscall in stack frame */
- err |= gen_return_code(frame->retcode, USE_SIGRETURN);
-
- if (err)
- goto give_sigsegv;
-
- /* Create signal handler execution context.
- * Return context not modified until this point.
- */
- set_thread_state(regs, frame, frame->retcode,
- ka->sa.sa_handler, signal, &frame->sc, NULL);
-
- /* Set access mode to USER_DS. Nomenclature is outdated, but
- * functionality is used in uaccess.h
- */
- set_fs(USER_DS);
-
-
-#if DEBUG_SIG
- printk("SIG deliver (%s:%d): signal=%d sp=%p pc=%08x\n",
- current->comm, current->pid, signal, frame, regs->pc);
-#endif
-
- return;
-
-give_sigsegv:
- if (sig == SIGSEGV)
- ka->sa.sa_handler = SIG_DFL;
- force_sig(SIGSEGV, current);
-}
-
-static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
- sigset_t *set, struct pt_regs *regs)
-{
- struct rt_sigframe *frame;
- int err = 0;
- int signal;
+ frame = (void *)((sp - sizeof(*frame)) & -16ul);
- frame = get_sigframe(ka, regs->areg[1], sizeof(*frame));
if (regs->depc > 64)
panic ("Double exception sys_sigreturn\n");
- if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+ if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) {
goto give_sigsegv;
+ }
signal = current_thread_info()->exec_domain
&& current_thread_info()->exec_domain->signal_invmap
@@ -602,9 +347,12 @@ static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
? current_thread_info()->exec_domain->signal_invmap[sig]
: sig;
- err |= copy_siginfo_to_user(&frame->info, info);
+ if (ka->sa.sa_flags & SA_SIGINFO) {
+ err |= copy_siginfo_to_user(&frame->info, info);
+ }
+
+ /* Create the user context. */
- /* Create the ucontext. */
err |= __put_user(0, &frame->uc.uc_flags);
err |= __put_user(0, &frame->uc.uc_link);
err |= __put_user((void *)current->sas_ss_sp,
@@ -617,16 +365,31 @@ static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
/* Create sys_rt_sigreturn syscall in stack frame */
- err |= gen_return_code(frame->retcode, USE_RT_SIGRETURN);
- if (err)
+ err |= gen_return_code(frame->retcode);
+
+ if (err) {
goto give_sigsegv;
+ }
+
- /* Create signal handler execution context.
+ /*
+ * Create signal handler execution context.
* Return context not modified until this point.
*/
- set_thread_state(regs, frame, frame->retcode,
- ka->sa.sa_handler, signal, &frame->info, &frame->uc);
+
+ /* Set up registers for signal handler */
+ start_thread(regs, (unsigned long) ka->sa.sa_handler,
+ (unsigned long) frame);
+
+ /* Set up a stack frame for a call4
+ * Note: PS.CALLINC is set to one by start_thread
+ */
+ ra = (unsigned long) frame->retcode;
+ regs->areg[4] = (((unsigned long) ra) & 0x3fffffff) | 0x40000000;
+ regs->areg[6] = (unsigned long) signal;
+ regs->areg[7] = (unsigned long) &frame->info;
+ regs->areg[8] = (unsigned long) &frame->uc;
/* Set access mode to USER_DS. Nomenclature is outdated, but
* functionality is used in uaccess.h
@@ -646,6 +409,48 @@ give_sigsegv:
force_sig(SIGSEGV, current);
}
+/*
+ * Atomically swap in the new signal mask, and wait for a signal.
+ */
+
+asmlinkage long xtensa_rt_sigsuspend(sigset_t __user *unewset,
+ size_t sigsetsize,
+ long a2, long a3, long a4, long a5,
+ struct pt_regs *regs)
+{
+ sigset_t saveset, newset;
+
+ /* XXX: Don't preclude handling different sized sigset_t's. */
+ if (sigsetsize != sizeof(sigset_t))
+ return -EINVAL;
+
+ if (copy_from_user(&newset, unewset, sizeof(newset)))
+ return -EFAULT;
+
+ sigdelsetmask(&newset, ~_BLOCKABLE);
+ spin_lock_irq(&current->sighand->siglock);
+ saveset = current->blocked;
+ current->blocked = newset;
+ recalc_sigpending();
+ spin_unlock_irq(&current->sighand->siglock);
+
+ regs->areg[2] = -EINTR;
+ while (1) {
+ current->state = TASK_INTERRUPTIBLE;
+ schedule();
+ if (do_signal(regs, &saveset))
+ return -EINTR;
+ }
+}
+
+asmlinkage long xtensa_sigaltstack(const stack_t __user *uss,
+ stack_t __user *uoss,
+ long a2, long a3, long a4, long a5,
+ struct pt_regs *regs)
+{
+ return do_sigaltstack(uss, uoss, regs->areg[1]);
+}
+
/*
@@ -663,51 +468,89 @@ int do_signal(struct pt_regs *regs, sigset_t *oldset)
int signr;
struct k_sigaction ka;
+ if (!user_mode(regs))
+ return 0;
+
+ if (try_to_freeze())
+ goto no_signal;
+
if (!oldset)
oldset = &current->blocked;
+ task_pt_regs(current)->icountlevel = 0;
+
signr = get_signal_to_deliver(&info, &ka, regs, NULL);
- /* Are we from a system call? */
- if (regs->syscall >= 0) {
- /* If so, check system call restarting.. */
- switch (regs->areg[2]) {
- case ERESTARTNOHAND:
- case ERESTART_RESTARTBLOCK:
- regs->areg[2] = -EINTR;
- break;
+ if (signr > 0) {
+
+ /* Are we from a system call? */
+
+ if ((signed)regs->syscall >= 0) {
- case ERESTARTSYS:
- if (!(ka.sa.sa_flags & SA_RESTART)) {
+ /* If so, check system call restarting.. */
+
+ switch (regs->areg[2]) {
+ case -ERESTARTNOHAND:
+ case -ERESTART_RESTARTBLOCK:
regs->areg[2] = -EINTR;
break;
- }
- /* fallthrough */
- case ERESTARTNOINTR:
- regs->areg[2] = regs->syscall;
- regs->pc -= 3;
+
+ case -ERESTARTSYS:
+ if (!(ka.sa.sa_flags & SA_RESTART)) {
+ regs->areg[2] = -EINTR;
+ break;
+ }
+ /* fallthrough */
+ case -ERESTARTNOINTR:
+ regs->areg[2] = regs->syscall;
+ regs->pc -= 3;
+ break;
+
+ default:
+ /* nothing to do */
+ if (regs->areg[2] != 0)
+ break;
+ }
}
- }
- if (signr == 0)
- return 0; /* no signals delivered */
+ /* Whee! Actually deliver the signal. */
+ /* Set up the stack frame */
+ setup_frame(signr, &ka, &info, oldset, regs);
- /* Whee! Actually deliver the signal. */
+ if (ka.sa.sa_flags & SA_ONESHOT)
+ ka.sa.sa_handler = SIG_DFL;
- /* Set up the stack frame */
- if (ka.sa.sa_flags & SA_SIGINFO)
- setup_rt_frame(signr, &ka, &info, oldset, regs);
- else
- setup_frame(signr, &ka, oldset, regs);
+ spin_lock_irq(&current->sighand->siglock);
+ sigorsets(&current->blocked, &current->blocked, &ka.sa.sa_mask);
+ if (!(ka.sa.sa_flags & SA_NODEFER))
+ sigaddset(&current->blocked, signr);
+ recalc_sigpending();
+ spin_unlock_irq(&current->sighand->siglock);
+ if (current->ptrace & PT_SINGLESTEP)
+ task_pt_regs(current)->icountlevel = 1;
- if (ka.sa.sa_flags & SA_ONESHOT)
- ka.sa.sa_handler = SIG_DFL;
+ return 1;
+ }
- spin_lock_irq(&current->sighand->siglock);
- sigorsets(&current->blocked, &current->blocked, &ka.sa.sa_mask);
- if (!(ka.sa.sa_flags & SA_NODEFER))
- sigaddset(&current->blocked, signr);
- recalc_sigpending();
- spin_unlock_irq(&current->sighand->siglock);
- return 1;
+no_signal:
+ /* Did we come from a system call? */
+ if ((signed) regs->syscall >= 0) {
+ /* Restart the system call - no handlers present */
+ switch (regs->areg[2]) {
+ case -ERESTARTNOHAND:
+ case -ERESTARTSYS:
+ case -ERESTARTNOINTR:
+ regs->areg[2] = regs->syscall;
+ regs->pc -= 3;
+ break;
+ case -ERESTART_RESTARTBLOCK:
+ regs->areg[2] = __NR_restart_syscall;
+ regs->pc -= 3;
+ break;
+ }
+ }
+ if (current->ptrace & PT_SINGLESTEP)
+ task_pt_regs(current)->icountlevel = 1;
+ return 0;
}
+
OpenPOWER on IntegriCloud