From ff7fbc72e0c3ef7e94a27a3a918fd09ec9a30204 Mon Sep 17 00:00:00 2001 From: Suresh Siddha Date: Mon, 22 Feb 2010 14:51:33 -0800 Subject: x86, ptrace: Simplify xstateregs_get() 48 bytes (bytes 464..511) of the xstateregs payload come from the kernel defined structure (xstate_fx_sw_bytes). Rest comes from the xstate regs structure in the thread struct. Instead of having multiple user_regset_copyout()'s, simplify the xstateregs_get() by first copying the SW bytes into the xstate regs structure in the thread structure and then using one user_regset_copyout() to copyout the xstateregs. Requested-by: Roland McGrath Signed-off-by: Suresh Siddha LKML-Reference: <20100222225240.494688491@sbs-t61.sc.intel.com> Acked-by: Roland McGrath Signed-off-by: H. Peter Anvin Cc: Oleg Nesterov --- arch/x86/kernel/i387.c | 30 +++++++----------------------- 1 file changed, 7 insertions(+), 23 deletions(-) (limited to 'arch/x86/kernel/i387.c') diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c index 7a8a193b5144..81e23bf12c12 100644 --- a/arch/x86/kernel/i387.c +++ b/arch/x86/kernel/i387.c @@ -243,34 +243,18 @@ int xstateregs_get(struct task_struct *target, const struct user_regset *regset, return ret; /* - * First copy the fxsave bytes 0..463. + * Copy the 48bytes defined by the software first into the xstate + * memory layout in the thread struct, so that we can copy the entire + * xstateregs to the user using one user_regset_copyout(). */ - ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, - &target->thread.xstate->xsave, 0, - offsetof(struct user_xstateregs, - i387.xstate_fx_sw)); - if (ret) - return ret; - - /* - * Copy the 48bytes defined by software. - */ - ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, - xstate_fx_sw_bytes, - offsetof(struct user_xstateregs, - i387.xstate_fx_sw), - offsetof(struct user_xstateregs, - xsave_hdr)); - if (ret) - return ret; + memcpy(&target->thread.xstate->fxsave.sw_reserved, + xstate_fx_sw_bytes, sizeof(xstate_fx_sw_bytes)); /* - * Copy the rest of xstate memory layout. + * Copy the xstate memory layout. */ ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, - &target->thread.xstate->xsave.xsave_hdr, - offsetof(struct user_xstateregs, - xsave_hdr), -1); + &target->thread.xstate->xsave, 0, -1); return ret; } -- cgit v1.2.3