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-rw-r--r--lib/libkse/arch/ia64/include/pthread_md.h6
-rw-r--r--lib/libpthread/arch/ia64/include/pthread_md.h6
-rw-r--r--sys/ia64/ia64/machdep.c36
-rw-r--r--sys/ia64/include/ucontext.h49
4 files changed, 41 insertions, 56 deletions
diff --git a/lib/libkse/arch/ia64/include/pthread_md.h b/lib/libkse/arch/ia64/include/pthread_md.h
index 6598f3d..a72c953 100644
--- a/lib/libkse/arch/ia64/include/pthread_md.h
+++ b/lib/libkse/arch/ia64/include/pthread_md.h
@@ -232,6 +232,12 @@ _thread_switch(struct kcb *kcb, struct tcb *tcb, int setmbox)
mc->mc_special.isr = (intptr_t)&tcb->tcb_tmbx;
}
_ia64_break_setcontext(mc);
+ } else if (mc->mc_flags & _MC_FLAGS_SYSCALL_CONTEXT) {
+ if (setmbox)
+ kse_switchin(mc, (long)&tcb->tcb_tmbx,
+ (long *)&kcb->kcb_kmbx.km_curthread);
+ else
+ kse_switchin(mc, 0L, NULL);
} else {
if (setmbox)
_ia64_restore_context(mc, (intptr_t)&tcb->tcb_tmbx,
diff --git a/lib/libpthread/arch/ia64/include/pthread_md.h b/lib/libpthread/arch/ia64/include/pthread_md.h
index 6598f3d..a72c953 100644
--- a/lib/libpthread/arch/ia64/include/pthread_md.h
+++ b/lib/libpthread/arch/ia64/include/pthread_md.h
@@ -232,6 +232,12 @@ _thread_switch(struct kcb *kcb, struct tcb *tcb, int setmbox)
mc->mc_special.isr = (intptr_t)&tcb->tcb_tmbx;
}
_ia64_break_setcontext(mc);
+ } else if (mc->mc_flags & _MC_FLAGS_SYSCALL_CONTEXT) {
+ if (setmbox)
+ kse_switchin(mc, (long)&tcb->tcb_tmbx,
+ (long *)&kcb->kcb_kmbx.km_curthread);
+ else
+ kse_switchin(mc, 0L, NULL);
} else {
if (setmbox)
_ia64_restore_context(mc, (intptr_t)&tcb->tcb_tmbx,
diff --git a/sys/ia64/ia64/machdep.c b/sys/ia64/ia64/machdep.c
index ddde791..28aa70c 100644
--- a/sys/ia64/ia64/machdep.c
+++ b/sys/ia64/ia64/machdep.c
@@ -1,4 +1,5 @@
/*-
+ * Copyright (c) 2003 Marcel Moolenaar
* Copyright (c) 2000,2001 Doug Rabson
* All rights reserved.
*
@@ -915,7 +916,7 @@ sendsig(sig_t catcher, int sig, sigset_t *mask, u_long code)
mtx_unlock(&psp->ps_mtx);
PROC_UNLOCK(p);
- get_mcontext(td, &sf.sf_uc.uc_mcontext, GET_MC_IA64_SCRATCH);
+ get_mcontext(td, &sf.sf_uc.uc_mcontext, 0);
/* Copy the frame out to userland. */
if (copyout(&sf, sfp, sizeof(sf)) != 0) {
@@ -1067,24 +1068,13 @@ get_mcontext(struct thread *td, mcontext_t *mc, int flags)
} else
mc->mc_special = tf->tf_special;
if (tf->tf_flags & FRAME_SYSCALL) {
- if (flags & GET_MC_IA64_SCRATCH) {
- mc->mc_flags |= _MC_FLAGS_SCRATCH_VALID;
- mc->mc_scratch = tf->tf_scratch;
- } else {
- /*
- * Put the syscall return values in the context. We
- * need this for swapcontext() to work. Note that we
- * don't use gr11 in the kernel, but the runtime
- * specification defines it as a return register,
- * just like gr8-gr10.
- */
- mc->mc_flags |= _MC_FLAGS_RETURN_VALID;
- if ((flags & GET_MC_CLEAR_RET) == 0) {
- mc->mc_scratch.gr8 = tf->tf_scratch.gr8;
- mc->mc_scratch.gr9 = tf->tf_scratch.gr9;
- mc->mc_scratch.gr10 = tf->tf_scratch.gr10;
- mc->mc_scratch.gr11 = tf->tf_scratch.gr11;
- }
+ mc->mc_flags |= _MC_FLAGS_SYSCALL_CONTEXT;
+ mc->mc_scratch = tf->tf_scratch;
+ if (flags & GET_MC_CLEAR_RET) {
+ mc->mc_scratch.gr8 = 0;
+ mc->mc_scratch.gr9 = 0;
+ mc->mc_scratch.gr10 = 0;
+ mc->mc_scratch.gr11 = 0;
}
} else {
mc->mc_flags |= _MC_FLAGS_ASYNC_CONTEXT;
@@ -1141,16 +1131,10 @@ set_mcontext(struct thread *td, const mcontext_t *mc)
td->td_pcb->pcb_high_fp = mc->mc_high_fp;
} else {
KASSERT((tf->tf_flags & FRAME_SYSCALL) != 0, ("foo"));
- if ((mc->mc_flags & _MC_FLAGS_SCRATCH_VALID) == 0) {
+ if ((mc->mc_flags & _MC_FLAGS_SYSCALL_CONTEXT) == 0) {
s.cfm = tf->tf_special.cfm;
s.iip = tf->tf_special.iip;
tf->tf_scratch.gr15 = 0; /* Clear syscall nr. */
- if (mc->mc_flags & _MC_FLAGS_RETURN_VALID) {
- tf->tf_scratch.gr8 = mc->mc_scratch.gr8;
- tf->tf_scratch.gr9 = mc->mc_scratch.gr9;
- tf->tf_scratch.gr10 = mc->mc_scratch.gr10;
- tf->tf_scratch.gr11 = mc->mc_scratch.gr11;
- }
} else
tf->tf_scratch = mc->mc_scratch;
}
diff --git a/sys/ia64/include/ucontext.h b/sys/ia64/include/ucontext.h
index 0ff1e29..5619d59 100644
--- a/sys/ia64/include/ucontext.h
+++ b/sys/ia64/include/ucontext.h
@@ -45,48 +45,42 @@
* call to the function that creates the context. An asynctx needs to have the
* scratch registers preserved because it can describe any point in a thread's
* (or process') execution.
+ * The second variation is for synchronous contexts. When the kernel creates
+ * a synchronous context if needs to preserve the scratch registers, because
+ * the syscall argument and return values are stored there in the trapframe
+ * and they need to be preserved in order to restart a syscall or return the
+ * proper return values. Also, the IIP and CFM fields need to be preserved
+ * as they point to the syscall stub, which the kernel saves as a favor to
+ * userland (it keeps the stubs small and simple).
*
* Below a description of the flags and their meaning:
*
* _MC_FLAGS_ASYNC_CONTEXT
* If set, indicates that mc_scratch and mc_scratch_fp are both
- * valid. IFF not set, _MC_FLAGS_RETURN_VALID indicates if the
- * return registers are valid or not.
+ * valid. IFF not set, _MC_FLAGS_SYSCALL_CONTEXT indicates if the
+ * synchronous context is one corresponding to a syscall or not.
+ * Only the kernel is expected to create such a context and it's
+ * probably wise to let the kernel restore it.
* _MC_FLAGS_HIGHFP_VALID
* If set, indicates that the high FP registers (f32-f127) are
* valid. This flag is very likely not going to be set for any
* sensible synctx, but is not explicitly disallowed. Any synctx
* that has this flag may or may not have the high FP registers
* restored. In short: don't do it.
- * _MC_FLAGS_KSE_SET_MBOX
- * This flag is special to setcontext(2) and swapcontext(2). It
- * instructs the kernel to write the value in mc_special.isr to
- * the memory address pointed to by mc_special.ifa. This allows
- * the kernel to switch to a new context in a KSE based threaded
- * program. Note that this is a non-srandard extension to the
- * otherwise standard system calls and use of this flag should be
- * limited to KSE.
- * _MC_FLAGS_RETURN_VALID
- * If set and _MC_FLAGS_ASYNC_CONTEXT is not set indicates that
- * the ABI defined return registers are valid. Both getcontext(2)
- * and swapcontext(2) need to save the system call return values.
- * Any synctx that does not have this flag may still have the
- * return registers restored from the context.
- * _MC_FLAGS_SCRATCH_VALID
- * If set and _MC_FLAGS_ASYNC_CONTEXT is not set indicates that
- * the scratch registers, but not the FP registers are valid.
- * This flag is set in contexts passed to signal handlers. This
- * flag is a superset of _MC_FLAGS_RETURN_VALID. If both flags
- * are set, this flag takes precedence.
+ * _MC_FLAGS_SYSCALL_CONTEXT
+ * If set (hence _MC_FLAGS_ASYNC_CONTEXT is not set) indicates
+ * that the scratch registers contain syscall arguments and
+ * return values and that additionally IIP and CFM are valid.
+ * Only the kernel is expected to create such a context. It's
+ * probably wise to let the kernel restore it.
*/
typedef struct __mcontext {
unsigned long mc_flags;
#define _MC_FLAGS_ASYNC_CONTEXT 0x0001
#define _MC_FLAGS_HIGHFP_VALID 0x0002
-#define _MC_FLAGS_KSE_SET_MBOX 0x0004
-#define _MC_FLAGS_RETURN_VALID 0x0008
-#define _MC_FLAGS_SCRATCH_VALID 0x0010
+#define _MC_FLAGS_KSE_SET_MBOX 0x0004 /* Undocumented. Has to go. */
+#define _MC_FLAGS_SYSCALL_CONTEXT 0x0008
unsigned long _reserved_;
struct _special mc_special;
struct _callee_saved mc_preserved;
@@ -96,9 +90,4 @@ typedef struct __mcontext {
struct _high_fp mc_high_fp;
} mcontext_t;
-#ifdef _KERNEL
-/* Flags for get_mcontext(). See also <sys/ucontext.h>. */
-#define GET_MC_IA64_SCRATCH 0x10
-#endif
-
#endif /* !_MACHINE_UCONTEXT_H_ */
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