git: 4b6a3ed70d8c - stable/13 - linux(4): In preparation for xsave refactor fxsave code on amd64
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Date: Thu, 29 Jun 2023 08:20:50 UTC
The branch stable/13 has been updated by dchagin:
URL: https://cgit.FreeBSD.org/src/commit/?id=4b6a3ed70d8cda6463320c464d4eff11f4aaf526
commit 4b6a3ed70d8cda6463320c464d4eff11f4aaf526
Author: Dmitry Chagin <dchagin@FreeBSD.org>
AuthorDate: 2023-06-08 22:32:46 +0000
Commit: Dmitry Chagin <dchagin@FreeBSD.org>
CommitDate: 2023-06-29 08:16:02 +0000
linux(4): In preparation for xsave refactor fxsave code on amd64
Due to fxsave area is os independent reimplement fxsave handmade code
using copying of a whole area.
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D40443
MFC after: 2 weeks
(cherry picked from commit 920184ed6e43b19f4b71253b55fd3ba66a7f0bb2)
---
sys/amd64/linux/linux_sysvec.c | 126 ++++++++++++++++++++-----------------
sys/x86/linux/linux_x86_sigframe.h | 9 ++-
2 files changed, 76 insertions(+), 59 deletions(-)
diff --git a/sys/amd64/linux/linux_sysvec.c b/sys/amd64/linux/linux_sysvec.c
index 2383a4dd6632..97f49f8a7727 100644
--- a/sys/amd64/linux/linux_sysvec.c
+++ b/sys/amd64/linux/linux_sysvec.c
@@ -79,6 +79,10 @@ __FBSDID("$FreeBSD$");
#include <x86/linux/linux_x86_sigframe.h>
+_Static_assert(sizeof(struct l_fpstate) ==
+ sizeof(__typeof(((mcontext_t *)0)->mc_fpstate)),
+ "fxsave area size incorrect");
+
MODULE_VERSION(linux64, 1);
#define LINUX_VDSOPAGE_SIZE PAGE_SIZE * 2
@@ -277,6 +281,31 @@ linux_exec_setregs(struct thread *td, struct image_params *imgp,
fpstate_drop(td);
}
+static int
+linux_fxrstor(struct thread *td, mcontext_t *mcp, struct l_sigcontext *sc)
+{
+ struct savefpu *fp = (struct savefpu *)&mcp->mc_fpstate[0];
+ int error;
+
+ error = copyin(PTRIN(sc->sc_fpstate), fp, sizeof(mcp->mc_fpstate));
+ if (error != 0)
+ return (error);
+ bzero(&fp->sv_pad[0], sizeof(fp->sv_pad));
+ return (set_fpcontext(td, mcp, NULL, 0));
+}
+
+static int
+linux_copyin_fpstate(struct thread *td, struct l_ucontext *uc)
+{
+ mcontext_t mc;
+
+ bzero(&mc, sizeof(mc));
+ mc.mc_ownedfp = _MC_FPOWNED_FPU;
+ mc.mc_fpformat = _MC_FPFMT_XMM;
+
+ return (linux_fxrstor(td, &mc, &uc->uc_mcontext));
+}
+
/*
* Copied from amd64/amd64/machdep.c
*/
@@ -287,10 +316,9 @@ linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args)
struct l_rt_sigframe sf;
struct l_sigcontext *context;
struct trapframe *regs;
- mcontext_t mc;
unsigned long rflags;
sigset_t bmask;
- int error, i;
+ int error;
ksiginfo_t ksi;
regs = td->td_frame;
@@ -362,41 +390,42 @@ linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args)
regs->tf_err = context->sc_err;
regs->tf_rflags = rflags;
- if (sf.sf_uc.uc_mcontext.sc_fpstate != NULL) {
- struct savefpu *svfp = (struct savefpu *)mc.mc_fpstate;
-
- bzero(&mc, sizeof(mc));
- mc.mc_ownedfp = _MC_FPOWNED_FPU;
- mc.mc_fpformat = _MC_FPFMT_XMM;
-
- svfp->sv_env.en_cw = sf.sf_fs.cwd;
- svfp->sv_env.en_sw = sf.sf_fs.swd;
- svfp->sv_env.en_tw = sf.sf_fs.twd;
- svfp->sv_env.en_opcode = sf.sf_fs.fop;
- svfp->sv_env.en_rip = sf.sf_fs.rip;
- svfp->sv_env.en_rdp = sf.sf_fs.rdp;
- svfp->sv_env.en_mxcsr = sf.sf_fs.mxcsr;
- svfp->sv_env.en_mxcsr_mask = sf.sf_fs.mxcsr_mask;
- /* FPU registers */
- for (i = 0; i < nitems(svfp->sv_fp); ++i)
- bcopy(&sf.sf_fs.st[i], svfp->sv_fp[i].fp_acc.fp_bytes,
- sizeof(svfp->sv_fp[i].fp_acc.fp_bytes));
- /* SSE registers */
- for (i = 0; i < nitems(svfp->sv_xmm); ++i)
- bcopy(&sf.sf_fs.xmm[i], svfp->sv_xmm[i].xmm_bytes,
- sizeof(svfp->sv_xmm[i].xmm_bytes));
- error = set_fpcontext(td, &mc, NULL, 0);
- if (error != 0) {
- uprintf("pid %d comm %s linux can't restore fpu state %d\n",
- p->p_pid, p->p_comm, error);
- return (error);
- }
+ error = linux_copyin_fpstate(td, &sf.sf_uc);
+ if (error != 0) {
+ uprintf("pid %d comm %s linux can't restore fpu state %d\n",
+ p->p_pid, p->p_comm, error);
+ return (error);
}
set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
return (EJUSTRETURN);
}
+static int
+linux_fxsave(mcontext_t *mcp, void *ufp)
+{
+ struct l_fpstate *fx = (struct l_fpstate *)&mcp->mc_fpstate[0];
+
+ bzero(&fx->reserved2[0], sizeof(fx->reserved2));
+ return (copyout(fx, ufp, sizeof(*fx)));
+}
+
+static int
+linux_copyout_fpstate(struct thread *td, struct l_ucontext *uc, char **sp)
+{
+ mcontext_t mc;
+ char *ufp = *sp;
+
+ get_fpcontext(td, &mc, NULL, NULL);
+ KASSERT(mc.mc_fpformat != _MC_FPFMT_NODEV, ("fpu not present"));
+
+ /* fxsave area */
+ ufp -= sizeof(struct l_fpstate);
+ *sp = ufp = (char *)((unsigned long)ufp & ~0x3Ful);
+
+ return (linux_fxsave(&mc, ufp));
+}
+
/*
* copied from amd64/amd64/machdep.c
*
@@ -411,10 +440,8 @@ linux_rt_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask)
struct sigacts *psp;
char *sp;
struct trapframe *regs;
- struct savefpu *svfp;
- mcontext_t mc;
int sig, code;
- int oonstack, issiginfo, i;
+ int oonstack, issiginfo;
td = curthread;
p = td->td_proc;
@@ -446,6 +473,14 @@ linux_rt_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask)
mtx_unlock(&psp->ps_mtx);
PROC_UNLOCK(p);
+ if (linux_copyout_fpstate(td, &sf.sf_uc, &sp) != 0) {
+ uprintf("pid %d comm %s linux can't save fpu state, killing\n",
+ p->p_pid, p->p_comm);
+ PROC_LOCK(p);
+ sigexit(td, SIGILL);
+ }
+ sf.sf_uc.uc_mcontext.sc_fpstate = (register_t)sp;
+
/* Make room, keeping the stack aligned. */
sp -= sizeof(struct l_rt_sigframe);
sfp = (struct l_rt_sigframe *)((unsigned long)sp & ~0xFul);
@@ -476,29 +511,6 @@ linux_rt_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask)
sf.sf_uc.uc_mcontext.sc_trapno = bsd_to_linux_trapcode(code);
sf.sf_uc.uc_mcontext.sc_cr2 = (register_t)ksi->ksi_addr;
- get_fpcontext(td, &mc, NULL, NULL);
- KASSERT(mc.mc_fpformat != _MC_FPFMT_NODEV, ("fpu not present"));
- svfp = (struct savefpu *)mc.mc_fpstate;
-
- sf.sf_fs.cwd = svfp->sv_env.en_cw;
- sf.sf_fs.swd = svfp->sv_env.en_sw;
- sf.sf_fs.twd = svfp->sv_env.en_tw;
- sf.sf_fs.fop = svfp->sv_env.en_opcode;
- sf.sf_fs.rip = svfp->sv_env.en_rip;
- sf.sf_fs.rdp = svfp->sv_env.en_rdp;
- sf.sf_fs.mxcsr = svfp->sv_env.en_mxcsr;
- sf.sf_fs.mxcsr_mask = svfp->sv_env.en_mxcsr_mask;
- /* FPU registers */
- for (i = 0; i < nitems(svfp->sv_fp); ++i)
- bcopy(svfp->sv_fp[i].fp_acc.fp_bytes, &sf.sf_fs.st[i],
- sizeof(svfp->sv_fp[i].fp_acc.fp_bytes));
- /* SSE registers */
- for (i = 0; i < nitems(svfp->sv_xmm); ++i)
- bcopy(svfp->sv_xmm[i].xmm_bytes, &sf.sf_fs.xmm[i],
- sizeof(svfp->sv_xmm[i].xmm_bytes));
- sf.sf_uc.uc_mcontext.sc_fpstate = (struct l_fpstate *)((char *)sfp +
- offsetof(struct l_rt_sigframe, sf_fs));
-
/* Translate the signal. */
sig = bsd_to_linux_signal(sig);
/* Fill in POSIX parts. */
diff --git a/sys/x86/linux/linux_x86_sigframe.h b/sys/x86/linux/linux_x86_sigframe.h
index 74e7a36e2e71..e5687069651f 100644
--- a/sys/x86/linux/linux_x86_sigframe.h
+++ b/sys/x86/linux/linux_x86_sigframe.h
@@ -170,7 +170,13 @@ struct l_sigcontext {
l_ulong sc_trapno;
l_sigset_t sc_mask;
l_ulong sc_cr2;
- struct l_fpstate *sc_fpstate;
+ /*
+ * On Linux sc_fpstate is (struct l_fpstate *) or (struct l_xstate *)
+ * depending on the FP_XSTATE_MAGIC1 encoded in the sw_reserved
+ * bytes of (struct l_fpstate) and FP_XSTATE_MAGIC2 present at the end
+ * of extended memory layout.
+ */
+ l_uintptr_t sc_fpstate;
l_ulong sc_reserved1[8];
};
@@ -189,7 +195,6 @@ struct l_ucontext {
struct l_rt_sigframe {
struct l_ucontext sf_uc;
struct l_siginfo sf_si;
- struct l_fpstate sf_fs;
};
#endif /* __i386__ || (__amd64__ && COMPAT_LINUX32) */