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Unroll copying of the registers in {g,s}et_mcontext() and limit it

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to the set actually restored by tl0_ret() instead of using the whole
trapframe. Additionally skip %g7 as that register is used as the
userland TLS pointer.

PR:		140523
MFC after:	1 week
This commit is contained in:
marius 2009-11-17 21:08:10 +00:00
parent c432accfde
commit abd64d9c68
1 changed files with 56 additions and 6 deletions
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62
sys/sparc64/sparc64/machdep.c
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@ -692,12 +692,39 @@ get_mcontext(struct thread *td, mcontext_t *mc, int flags)
tf = td->td_frame;
pcb = td->td_pcb;
bcopy(tf, mc, sizeof(*tf));
/*
* Copy the registers which will be restored by tl0_ret() from the
* trapframe.
* Note that we skip %g7 which is used as the userland TLS register
* and %wstate.
*/
mc->mc_flags = _MC_VERSION;
mc->mc_global[1] = tf->tf_global[1];
mc->mc_global[2] = tf->tf_global[2];
mc->mc_global[3] = tf->tf_global[3];
mc->mc_global[4] = tf->tf_global[4];
mc->mc_global[5] = tf->tf_global[5];
mc->mc_global[6] = tf->tf_global[6];
if (flags & GET_MC_CLEAR_RET) {
mc->mc_out[0] = 0;
mc->mc_out[1] = 0;
} else {
mc->mc_out[0] = tf->tf_out[0];
mc->mc_out[1] = tf->tf_out[1];
}
mc->mc_flags = _MC_VERSION;
mc->mc_out[2] = tf->tf_out[2];
mc->mc_out[3] = tf->tf_out[3];
mc->mc_out[4] = tf->tf_out[4];
mc->mc_out[5] = tf->tf_out[5];
mc->mc_out[6] = tf->tf_out[6];
mc->mc_out[7] = tf->tf_out[7];
mc->mc_fprs = tf->tf_fprs;
mc->mc_fsr = tf->tf_fsr;
mc->mc_gsr = tf->tf_gsr;
mc->mc_tnpc = tf->tf_tnpc;
mc->mc_tpc = tf->tf_tpc;
mc->mc_tstate = tf->tf_tstate;
mc->mc_y = tf->tf_y;
critical_enter();
if ((tf->tf_fprs & FPRS_FEF) != 0) {
savefpctx(pcb->pcb_ufp);
@ -717,7 +744,6 @@ set_mcontext(struct thread *td, const mcontext_t *mc)
{
struct trapframe *tf;
struct pcb *pcb;
uint64_t wstate;
if (!TSTATE_SECURE(mc->mc_tstate) ||
(mc->mc_flags & ((1L << _MC_VERSION_BITS) - 1)) != _MC_VERSION)
@ -726,9 +752,33 @@ set_mcontext(struct thread *td, const mcontext_t *mc)
pcb = td->td_pcb;
/* Make sure the windows are spilled first. */
flushw();
wstate = tf->tf_wstate;
bcopy(mc, tf, sizeof(*tf));
tf->tf_wstate = wstate;
/*
* Copy the registers which will be restored by tl0_ret() to the
* trapframe.
* Note that we skip %g7 which is used as the userland TLS register
* and %wstate.
*/
tf->tf_global[1] = mc->mc_global[1];
tf->tf_global[2] = mc->mc_global[2];
tf->tf_global[3] = mc->mc_global[3];
tf->tf_global[4] = mc->mc_global[4];
tf->tf_global[5] = mc->mc_global[5];
tf->tf_global[6] = mc->mc_global[6];
tf->tf_out[0] = mc->mc_out[0];
tf->tf_out[1] = mc->mc_out[1];
tf->tf_out[2] = mc->mc_out[2];
tf->tf_out[3] = mc->mc_out[3];
tf->tf_out[4] = mc->mc_out[4];
tf->tf_out[5] = mc->mc_out[5];
tf->tf_out[6] = mc->mc_out[6];
tf->tf_out[7] = mc->mc_out[7];
tf->tf_fprs = mc->mc_fprs;
tf->tf_fsr = mc->mc_fsr;
tf->tf_gsr = mc->mc_gsr;
tf->tf_tnpc = mc->mc_tnpc;
tf->tf_tpc = mc->mc_tpc;
tf->tf_tstate = mc->mc_tstate;
tf->tf_y = mc->mc_y;
if ((mc->mc_fprs & FPRS_FEF) != 0) {
tf->tf_fprs = 0;
bcopy(mc->mc_fp, pcb->pcb_ufp, sizeof(pcb->pcb_ufp));