[SPARC32]: Add user regset support.

It is missing lazy FPU handling for the current task,
but that can be added later.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 284 insertions, 1 deletions

diff --git a/arch/sparc/kernel/ptrace.c b/arch/sparc/kernel/ptrace.c
index 7452269bba2a..c1e7e6ae7c6f 100644
--- a/arch/sparc/kernel/ptrace.c
+++ b/arch/sparc/kernel/ptrace.c
@@ -1,6 +1,6 @@
 /* ptrace.c: Sparc process tracing support.
  *
- * Copyright (C) 1996 David S. Miller (davem@caipfs.rutgers.edu)
+ * Copyright (C) 1996, 2008 David S. Miller (davem@davemloft.net)
  *
  * Based upon code written by Ross Biro, Linus Torvalds, Bob Manson,
  * and David Mosberger.
@@ -19,6 +19,8 @@
 #include <linux/smp_lock.h>
 #include <linux/security.h>
 #include <linux/signal.h>
+#include <linux/regset.h>
+#include <linux/elf.h>
 
 #include <asm/pgtable.h>
 #include <asm/system.h>
@@ -258,6 +260,287 @@ void ptrace_disable(struct task_struct *child)
         /* nothing to do */
 }
 
+enum sparc_regset {
+        REGSET_GENERAL,
+        REGSET_FP,
+};
+
+static int genregs32_get(struct task_struct *target,
+                         const struct user_regset *regset,
+                         unsigned int pos, unsigned int count,
+                         void *kbuf, void __user *ubuf)
+{
+        const struct pt_regs *regs = target->thread.kregs;
+        unsigned long __user *reg_window;
+        unsigned long *k = kbuf;
+        unsigned long __user *u = ubuf;
+        unsigned long reg;
+
+        if (target == current)
+                flush_user_windows();
+
+        pos /= sizeof(reg);
+        count /= sizeof(reg);
+
+        if (kbuf) {
+                for (; count > 0 && pos < 16; count--)
+                        *k++ = regs->u_regs[pos++];
+
+                reg_window = (unsigned long __user *) regs->u_regs[UREG_I6];
+                for (; count > 0 && pos < 32; count--) {
+                        if (get_user(*k++, &reg_window[pos++]))
+                                return -EFAULT;
+                }
+        } else {
+                for (; count > 0 && pos < 16; count--) {
+                        if (put_user(regs->u_regs[pos++], u++))
+                                return -EFAULT;
+                }
+
+                reg_window = (unsigned long __user *) regs->u_regs[UREG_I6];
+                for (; count > 0 && pos < 32; count--) {
+                        if (get_user(reg, &reg_window[pos++]) ||
+                            put_user(reg, u++))
+                                return -EFAULT;
+                }
+        }
+        while (count > 0) {
+                switch (pos) {
+                case 32: /* PSR */
+                        reg = regs->psr;
+                        break;
+                case 33: /* PC */
+                        reg = regs->pc;
+                        break;
+                case 34: /* NPC */
+                        reg = regs->npc;
+                        break;
+                case 35: /* Y */
+                        reg = regs->y;
+                        break;
+                case 36: /* WIM */
+                case 37: /* TBR */
+                        reg = 0;
+                        break;
+                default:
+                        goto finish;
+                }
+
+                if (kbuf)
+                        *k++ = reg;
+                else if (put_user(reg, u++))
+                        return -EFAULT;
+                pos++;
+                count--;
+        }
+finish:
+        pos *= sizeof(reg);
+        count *= sizeof(reg);
+
+        return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
+                                        38 * sizeof(reg), -1);
+}
+
+static int genregs32_set(struct task_struct *target,
+                         const struct user_regset *regset,
+                         unsigned int pos, unsigned int count,
+                         const void *kbuf, const void __user *ubuf)
+{
+        struct pt_regs *regs = target->thread.kregs;
+        unsigned long __user *reg_window;
+        const unsigned long *k = kbuf;
+        const unsigned long __user *u = ubuf;
+        unsigned long reg;
+
+        if (target == current)
+                flush_user_windows();
+
+        pos /= sizeof(reg);
+        count /= sizeof(reg);
+
+        if (kbuf) {
+                for (; count > 0 && pos < 16; count--)
+                        regs->u_regs[pos++] = *k++;
+
+                reg_window = (unsigned long __user *) regs->u_regs[UREG_I6];
+                for (; count > 0 && pos < 32; count--) {
+                        if (put_user(*k++, &reg_window[pos++]))
+                                return -EFAULT;
+                }
+        } else {
+                for (; count > 0 && pos < 16; count--) {
+                        if (get_user(reg, u++))
+                                return -EFAULT;
+                        regs->u_regs[pos++] = reg;
+                }
+
+                reg_window = (unsigned long __user *) regs->u_regs[UREG_I6];
+                for (; count > 0 && pos < 32; count--) {
+                        if (get_user(reg, u++) ||
+                            put_user(reg, &reg_window[pos++]))
+                                return -EFAULT;
+                }
+        }
+        while (count > 0) {
+                unsigned long psr;
+
+                if (kbuf)
+                        reg = *k++;
+                else if (get_user(reg, u++))
+                        return -EFAULT;
+
+                switch (pos) {
+                case 32: /* PSR */
+                        psr = regs->psr;
+                        psr &= ~PSR_ICC;
+                        psr |= (reg & PSR_ICC);
+                        regs->psr = psr;
+                        break;
+                case 33: /* PC */
+                        regs->pc = reg;
+                        break;
+                case 34: /* NPC */
+                        regs->npc = reg;
+                        break;
+                case 35: /* Y */
+                        regs->y = reg;
+                        break;
+                case 36: /* WIM */
+                case 37: /* TBR */
+                        break;
+                default:
+                        goto finish;
+                }
+
+                pos++;
+                count--;
+        }
+finish:
+        pos *= sizeof(reg);
+        count *= sizeof(reg);
+
+        return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
+                                         38 * sizeof(reg), -1);
+}
+
+static int fpregs32_get(struct task_struct *target,
+                        const struct user_regset *regset,
+                        unsigned int pos, unsigned int count,
+                        void *kbuf, void __user *ubuf)
+{
+        const unsigned long *fpregs = target->thread.float_regs;
+        int ret = 0;
+
+#if 0
+        if (target == current)
+                save_and_clear_fpu();
+#endif
+
+        ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
+                                  fpregs,
+                                  0, 32 * sizeof(u32));
+
+        if (!ret)
+                ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
+                                               32 * sizeof(u32),
+                                               33 * sizeof(u32));
+        if (!ret)
+                ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
+                                          &target->thread.fsr,
+                                          33 * sizeof(u32),
+                                          34 * sizeof(u32));
+
+        if (!ret) {
+                unsigned long val;
+
+                val = (1 << 8) | (8 << 16);
+                ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
+                                          &val,
+                                          34 * sizeof(u32),
+                                          35 * sizeof(u32));
+        }
+
+        if (!ret)
+                ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
+                                               35 * sizeof(u32), -1);
+
+        return ret;
+}
+
+static int fpregs32_set(struct task_struct *target,
+                        const struct user_regset *regset,
+                        unsigned int pos, unsigned int count,
+                        const void *kbuf, const void __user *ubuf)
+{
+        unsigned long *fpregs = target->thread.float_regs;
+        int ret;
+
+#if 0
+        if (target == current)
+                save_and_clear_fpu();
+#endif
+        ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+                                 fpregs,
+                                 0, 32 * sizeof(u32));
+        if (!ret)
+                user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
+                                          32 * sizeof(u32),
+                                          33 * sizeof(u32));
+        if (!ret && count > 0) {
+                ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+                                         &target->thread.fsr,
+                                         33 * sizeof(u32),
+                                         34 * sizeof(u32));
+        }
+
+        if (!ret)
+                ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
+                                                34 * sizeof(u32), -1);
+        return ret;
+}
+
+static const struct user_regset sparc32_regsets[] = {
+        /* Format is:
+         *      G0 --> G7
+         *      O0 --> O7
+         *      L0 --> L7
+         *      I0 --> I7
+         *      PSR, PC, nPC, Y, WIM, TBR
+         */
+        [REGSET_GENERAL] = {
+                .core_note_type = NT_PRSTATUS,
+                .n = 38 * sizeof(u32),
+                .size = sizeof(u32), .align = sizeof(u32),
+                .get = genregs32_get, .set = genregs32_set
+        },
+        /* Format is:
+         *      F0 --> F31
+         *      empty 32-bit word
+         *      FSR (32--bit word)
+         *      FPU QUEUE COUNT (8-bit char)
+         *      FPU QUEUE ENTRYSIZE (8-bit char)
+         *      FPU ENABLED (8-bit char)
+         *      empty 8-bit char
+         *      FPU QUEUE (64 32-bit ints)
+         */
+        [REGSET_FP] = {
+                .core_note_type = NT_PRFPREG,
+                .n = 99 * sizeof(u32),
+                .size = sizeof(u32), .align = sizeof(u32),
+                .get = fpregs32_get, .set = fpregs32_set
+        },
+};
+
+static const struct user_regset_view user_sparc32_view = {
+        .name = "sparc", .e_machine = EM_SPARC,
+        .regsets = sparc32_regsets, .n = ARRAY_SIZE(sparc32_regsets)
+};
+
+const struct user_regset_view *task_user_regset_view(struct task_struct *task)
+{
+        return &user_sparc32_view;
+}
+
 asmlinkage void do_ptrace(struct pt_regs *regs)
 {
         unsigned long request = regs->u_regs[UREG_I0];