powerpc: Clean up copy_to/from_user for vsx and fpr

This merges and cleans up some of the ugly copy/to from user code
which is required for the new fpr and vsx layout in the thread_struct.

Also fixes some hard coded buffer sizes and removes a redundant
fpr_flush_to_thread.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

diff --git a/arch/powerpc/kernel/signal.h b/arch/powerpc/kernel/signal.h
index 77efb3d..28f4b9f 100644 (file)
--- a/arch/powerpc/kernel/signal.h
+++ b/arch/powerpc/kernel/signal.h
@@ -24,6 +24,16 @@ extern int handle_rt_signal32(unsigned long sig, struct k_sigaction *ka,
                              siginfo_t *info, sigset_t *oldset,
                              struct pt_regs *regs);
 
+extern unsigned long copy_fpr_to_user(void __user *to,
+                                     struct task_struct *task);
+extern unsigned long copy_fpr_from_user(struct task_struct *task,
+                                       void __user *from);
+#ifdef CONFIG_VSX
+extern unsigned long copy_vsx_to_user(void __user *to,
+                                     struct task_struct *task);
+extern unsigned long copy_vsx_from_user(struct task_struct *task,
+                                       void __user *from);
+#endif
 
 #ifdef CONFIG_PPC64
 

diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 349d348..9991e2a 100644 (file)
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -328,6 +328,75 @@ struct rt_sigframe {
        int                     abigap[56];
 };
 
+#ifdef CONFIG_VSX
+unsigned long copy_fpr_to_user(void __user *to,
+                              struct task_struct *task)
+{
+       double buf[ELF_NFPREG];
+       int i;
+
+       /* save FPR copy to local buffer then write to the thread_struct */
+       for (i = 0; i < (ELF_NFPREG - 1) ; i++)
+               buf[i] = task->thread.TS_FPR(i);
+       memcpy(&buf[i], &task->thread.fpscr, sizeof(double));
+       return __copy_to_user(to, buf, ELF_NFPREG * sizeof(double));
+}
+
+unsigned long copy_fpr_from_user(struct task_struct *task,
+                                void __user *from)
+{
+       double buf[ELF_NFPREG];
+       int i;
+
+       if (__copy_from_user(buf, from, ELF_NFPREG * sizeof(double)))
+               return 1;
+       for (i = 0; i < (ELF_NFPREG - 1) ; i++)
+               task->thread.TS_FPR(i) = buf[i];
+       memcpy(&task->thread.fpscr, &buf[i], sizeof(double));
+
+       return 0;
+}
+
+unsigned long copy_vsx_to_user(void __user *to,
+                              struct task_struct *task)
+{
+       double buf[ELF_NVSRHALFREG];
+       int i;
+
+       /* save FPR copy to local buffer then write to the thread_struct */
+       for (i = 0; i < ELF_NVSRHALFREG; i++)
+               buf[i] = task->thread.fpr[i][TS_VSRLOWOFFSET];
+       return __copy_to_user(to, buf, ELF_NVSRHALFREG * sizeof(double));
+}
+
+unsigned long copy_vsx_from_user(struct task_struct *task,
+                                void __user *from)
+{
+       double buf[ELF_NVSRHALFREG];
+       int i;
+
+       if (__copy_from_user(buf, from, ELF_NVSRHALFREG * sizeof(double)))
+               return 1;
+       for (i = 0; i < ELF_NVSRHALFREG ; i++)
+               task->thread.fpr[i][TS_VSRLOWOFFSET] = buf[i];
+       return 0;
+}
+#else
+inline unsigned long copy_fpr_to_user(void __user *to,
+                                     struct task_struct *task)
+{
+       return __copy_to_user(to, task->thread.fpr,
+                             ELF_NFPREG * sizeof(double));
+}
+
+inline unsigned long copy_fpr_from_user(struct task_struct *task,
+                                       void __user *from)
+{
+       return __copy_from_user(task->thread.fpr, from,
+                             ELF_NFPREG * sizeof(double));
+}
+#endif
+
 /*
  * Save the current user registers on the user stack.
  * We only save the altivec/spe registers if the process has used
@@ -337,10 +406,6 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
                int sigret)
 {
        unsigned long msr = regs->msr;
-#ifdef CONFIG_VSX
-       double buf[32];
-       int i;
-#endif
 
        /* Make sure floating point registers are stored in regs */
        flush_fp_to_thread(current);
@@ -370,14 +435,9 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
        if (__put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32]))
                return 1;
 #endif /* CONFIG_ALTIVEC */
-#ifdef CONFIG_VSX
-       /* save FPR copy to local buffer then write to the thread_struct */
-       flush_fp_to_thread(current);
-       for (i = 0; i < 32 ; i++)
-               buf[i] = current->thread.TS_FPR(i);
-       memcpy(&buf[i], &current->thread.fpscr, sizeof(double));
-       if (__copy_to_user(&frame->mc_fregs, buf, ELF_NFPREG * sizeof(double)))
+       if (copy_fpr_to_user(&frame->mc_fregs, current))
                return 1;
+#ifdef CONFIG_VSX
        /*
         * Copy VSR 0-31 upper half from thread_struct to local
         * buffer, then write that to userspace.  Also set MSR_VSX in
@@ -386,18 +446,10 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
         */
        if (current->thread.used_vsr) {
                flush_vsx_to_thread(current);
-               for (i = 0; i < 32 ; i++)
-                       buf[i] = current->thread.fpr[i][TS_VSRLOWOFFSET];
-               if (__copy_to_user(&frame->mc_vsregs, buf,
-                                  ELF_NVSRHALFREG  * sizeof(double)))
+               if (copy_vsx_to_user(&frame->mc_vsregs, current))
                        return 1;
                msr |= MSR_VSX;
        }
-#else
-       /* save floating-point registers */
-       if (__copy_to_user(&frame->mc_fregs, current->thread.fpr,
-                   ELF_NFPREG * sizeof(double)))
-               return 1;
 #endif /* CONFIG_VSX */
 #ifdef CONFIG_SPE
        /* save spe registers */
@@ -442,7 +494,6 @@ static long restore_user_regs(struct pt_regs *regs,
        unsigned int save_r2 = 0;
        unsigned long msr;
 #ifdef CONFIG_VSX
-       double buf[32];
        int i;
 #endif
 
@@ -490,13 +541,10 @@ static long restore_user_regs(struct pt_regs *regs,
        if (__get_user(current->thread.vrsave, (u32 __user *)&sr->mc_vregs[32]))
                return 1;
 #endif /* CONFIG_ALTIVEC */
+       if (copy_fpr_from_user(current, &sr->mc_fregs))
+               return 1;
 
 #ifdef CONFIG_VSX
-       if (__copy_from_user(buf, &sr->mc_fregs,sizeof(sr->mc_fregs)))
-               return 1;
-       for (i = 0; i < 32 ; i++)
-               current->thread.TS_FPR(i) = buf[i];
-       memcpy(&current->thread.fpscr, &buf[i], sizeof(double));
        /*
         * Force the process to reload the VSX registers from
         * current->thread when it next does VSX instruction.
@@ -507,18 +555,11 @@ static long restore_user_regs(struct pt_regs *regs,
                 * Restore altivec registers from the stack to a local
                 * buffer, then write this out to the thread_struct
                 */
-               if (__copy_from_user(buf, &sr->mc_vsregs,
-                                    sizeof(sr->mc_vsregs)))
+               if (copy_vsx_from_user(current, &sr->mc_vsregs))
                        return 1;
-               for (i = 0; i < 32 ; i++)
-                       current->thread.fpr[i][TS_VSRLOWOFFSET] = buf[i];
        } else if (current->thread.used_vsr)
                for (i = 0; i < 32 ; i++)
                        current->thread.fpr[i][TS_VSRLOWOFFSET] = 0;
-#else
-       if (__copy_from_user(current->thread.fpr, &sr->mc_fregs,
-                            sizeof(sr->mc_fregs)))
-               return 1;
 #endif /* CONFIG_VSX */
        /*
         * force the process to reload the FP registers from

diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index 8214e57..93ebfb6 100644 (file)
--- a/arch/powerpc/kernel/signal_64.c
+++ b/arch/powerpc/kernel/signal_64.c
@@ -89,10 +89,6 @@ static long setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
 #endif
        unsigned long msr = regs->msr;
        long err = 0;
-#ifdef CONFIG_VSX
-       double buf[FP_REGS_SIZE];
-       int i;
-#endif
 
        flush_fp_to_thread(current);
 
@@ -117,12 +113,9 @@ static long setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
        err |= __put_user(0, &sc->v_regs);
 #endif /* CONFIG_ALTIVEC */
        flush_fp_to_thread(current);
+       /* copy fpr regs and fpscr */
+       err |= copy_fpr_to_user(&sc->fp_regs, current);
 #ifdef CONFIG_VSX
-       /* Copy FP to local buffer then write that out */
-       for (i = 0; i < 32 ; i++)
-               buf[i] = current->thread.TS_FPR(i);
-       memcpy(&buf[i], &current->thread.fpscr, sizeof(double));
-       err |= __copy_to_user(&sc->fp_regs, buf, FP_REGS_SIZE);
        /*
         * Copy VSX low doubleword to local buffer for formatting,
         * then out to userspace.  Update v_regs to point after the
@@ -131,17 +124,12 @@ static long setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
        if (current->thread.used_vsr) {
                flush_vsx_to_thread(current);
                v_regs += ELF_NVRREG;
-               for (i = 0; i < 32 ; i++)
-                       buf[i] = current->thread.fpr[i][TS_VSRLOWOFFSET];
-               err |= __copy_to_user(v_regs, buf, 32 * sizeof(double));
+               err |= copy_vsx_to_user(v_regs, current);
                /* set MSR_VSX in the MSR value in the frame to
                 * indicate that sc->vs_reg) contains valid data.
                 */
                msr |= MSR_VSX;
        }
-#else /* CONFIG_VSX */
-       /* copy fpr regs and fpscr */
-       err |= __copy_to_user(&sc->fp_regs, &current->thread.fpr, FP_REGS_SIZE);
 #endif /* CONFIG_VSX */
        err |= __put_user(&sc->gp_regs, &sc->regs);
        WARN_ON(!FULL_REGS(regs));
@@ -165,13 +153,12 @@ static long restore_sigcontext(struct pt_regs *regs, sigset_t *set, int sig,
 #ifdef CONFIG_ALTIVEC
        elf_vrreg_t __user *v_regs;
 #endif
-#ifdef CONFIG_VSX
-       double buf[FP_REGS_SIZE];
-       int i;
-#endif
        unsigned long err = 0;
        unsigned long save_r13 = 0;
        unsigned long msr;
+#ifdef CONFIG_VSX
+       int i;
+#endif
 
        /* If this is not a signal return, we preserve the TLS in r13 */
        if (!sig)
@@ -234,15 +221,9 @@ static long restore_sigcontext(struct pt_regs *regs, sigset_t *set, int sig,
        else
                current->thread.vrsave = 0;
 #endif /* CONFIG_ALTIVEC */
-#ifdef CONFIG_VSX
        /* restore floating point */
-       err |= __copy_from_user(buf, &sc->fp_regs, FP_REGS_SIZE);
-       if (err)
-               return err;
-       for (i = 0; i < 32 ; i++)
-               current->thread.TS_FPR(i) = buf[i];
-       memcpy(&current->thread.fpscr, &buf[i], sizeof(double));
-
+       err |= copy_fpr_from_user(current, &sc->fp_regs);
+#ifdef CONFIG_VSX
        /*
         * Get additional VSX data. Update v_regs to point after the
         * VMX data.  Copy VSX low doubleword from userspace to local
@@ -250,14 +231,12 @@ static long restore_sigcontext(struct pt_regs *regs, sigset_t *set, int sig,
         */
        v_regs += ELF_NVRREG;
        if ((msr & MSR_VSX) != 0)
-               err |= __copy_from_user(buf, v_regs, 32 * sizeof(double));
+               err |= copy_vsx_from_user(current, v_regs);
        else
-               memset(buf, 0, 32 * sizeof(double));
+               for (i = 0; i < 32 ; i++)
+                       current->thread.fpr[i][TS_VSRLOWOFFSET] = 0;
 
-       for (i = 0; i < 32 ; i++)
-               current->thread.fpr[i][TS_VSRLOWOFFSET] = buf[i];
 #else
-       err |= __copy_from_user(&current->thread.fpr, &sc->fp_regs, FP_REGS_SIZE);
 #endif
        return err;
 }