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-rw-r--r--arch/mips/kernel/process.c12
-rw-r--r--arch/mips/kernel/ptrace.c147
2 files changed, 134 insertions, 25 deletions
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
index c558bce989cd..6e716a5f1173 100644
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -683,6 +683,18 @@ int mips_set_process_fp_mode(struct task_struct *task, unsigned int value)
struct task_struct *t;
int max_users;
+ /* If nothing to change, return right away, successfully. */
+ if (value == mips_get_process_fp_mode(task))
+ return 0;
+
+ /* Only accept a mode change if 64-bit FP enabled for o32. */
+ if (!IS_ENABLED(CONFIG_MIPS_O32_FP64_SUPPORT))
+ return -EOPNOTSUPP;
+
+ /* And only for o32 tasks. */
+ if (IS_ENABLED(CONFIG_64BIT) && !test_thread_flag(TIF_32BIT_REGS))
+ return -EOPNOTSUPP;
+
/* Check the value is valid */
if (value & ~known_bits)
return -EOPNOTSUPP;
diff --git a/arch/mips/kernel/ptrace.c b/arch/mips/kernel/ptrace.c
index 11890e6e4093..0c8ae2cc6380 100644
--- a/arch/mips/kernel/ptrace.c
+++ b/arch/mips/kernel/ptrace.c
@@ -439,63 +439,160 @@ static int gpr64_set(struct task_struct *target,
#endif /* CONFIG_64BIT */
+/*
+ * Copy the floating-point context to the supplied NT_PRFPREG buffer,
+ * !CONFIG_CPU_HAS_MSA variant. FP context's general register slots
+ * correspond 1:1 to buffer slots. Only general registers are copied.
+ */
+static int fpr_get_fpa(struct task_struct *target,
+ unsigned int *pos, unsigned int *count,
+ void **kbuf, void __user **ubuf)
+{
+ return user_regset_copyout(pos, count, kbuf, ubuf,
+ &target->thread.fpu,
+ 0, NUM_FPU_REGS * sizeof(elf_fpreg_t));
+}
+
+/*
+ * Copy the floating-point context to the supplied NT_PRFPREG buffer,
+ * CONFIG_CPU_HAS_MSA variant. Only lower 64 bits of FP context's
+ * general register slots are copied to buffer slots. Only general
+ * registers are copied.
+ */
+static int fpr_get_msa(struct task_struct *target,
+ unsigned int *pos, unsigned int *count,
+ void **kbuf, void __user **ubuf)
+{
+ unsigned int i;
+ u64 fpr_val;
+ int err;
+
+ BUILD_BUG_ON(sizeof(fpr_val) != sizeof(elf_fpreg_t));
+ for (i = 0; i < NUM_FPU_REGS; i++) {
+ fpr_val = get_fpr64(&target->thread.fpu.fpr[i], 0);
+ err = user_regset_copyout(pos, count, kbuf, ubuf,
+ &fpr_val, i * sizeof(elf_fpreg_t),
+ (i + 1) * sizeof(elf_fpreg_t));
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
+/*
+ * Copy the floating-point context to the supplied NT_PRFPREG buffer.
+ * Choose the appropriate helper for general registers, and then copy
+ * the FCSR register separately.
+ */
static int fpr_get(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
- unsigned i;
+ const int fcr31_pos = NUM_FPU_REGS * sizeof(elf_fpreg_t);
int err;
- u64 fpr_val;
- /* XXX fcr31 */
+ if (sizeof(target->thread.fpu.fpr[0]) == sizeof(elf_fpreg_t))
+ err = fpr_get_fpa(target, &pos, &count, &kbuf, &ubuf);
+ else
+ err = fpr_get_msa(target, &pos, &count, &kbuf, &ubuf);
+ if (err)
+ return err;
- if (sizeof(target->thread.fpu.fpr[i]) == sizeof(elf_fpreg_t))
- return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
- &target->thread.fpu,
- 0, sizeof(elf_fpregset_t));
+ err = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
+ &target->thread.fpu.fcr31,
+ fcr31_pos, fcr31_pos + sizeof(u32));
- for (i = 0; i < NUM_FPU_REGS; i++) {
- fpr_val = get_fpr64(&target->thread.fpu.fpr[i], 0);
- err = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
- &fpr_val, i * sizeof(elf_fpreg_t),
- (i + 1) * sizeof(elf_fpreg_t));
+ return err;
+}
+
+/*
+ * Copy the supplied NT_PRFPREG buffer to the floating-point context,
+ * !CONFIG_CPU_HAS_MSA variant. Buffer slots correspond 1:1 to FP
+ * context's general register slots. Only general registers are copied.
+ */
+static int fpr_set_fpa(struct task_struct *target,
+ unsigned int *pos, unsigned int *count,
+ const void **kbuf, const void __user **ubuf)
+{
+ return user_regset_copyin(pos, count, kbuf, ubuf,
+ &target->thread.fpu,
+ 0, NUM_FPU_REGS * sizeof(elf_fpreg_t));
+}
+
+/*
+ * Copy the supplied NT_PRFPREG buffer to the floating-point context,
+ * CONFIG_CPU_HAS_MSA variant. Buffer slots are copied to lower 64
+ * bits only of FP context's general register slots. Only general
+ * registers are copied.
+ */
+static int fpr_set_msa(struct task_struct *target,
+ unsigned int *pos, unsigned int *count,
+ const void **kbuf, const void __user **ubuf)
+{
+ unsigned int i;
+ u64 fpr_val;
+ int err;
+
+ BUILD_BUG_ON(sizeof(fpr_val) != sizeof(elf_fpreg_t));
+ for (i = 0; i < NUM_FPU_REGS && *count > 0; i++) {
+ err = user_regset_copyin(pos, count, kbuf, ubuf,
+ &fpr_val, i * sizeof(elf_fpreg_t),
+ (i + 1) * sizeof(elf_fpreg_t));
if (err)
return err;
+ set_fpr64(&target->thread.fpu.fpr[i], 0, fpr_val);
}
return 0;
}
+/*
+ * Copy the supplied NT_PRFPREG buffer to the floating-point context.
+ * Choose the appropriate helper for general registers, and then copy
+ * the FCSR register separately.
+ *
+ * We optimize for the case where `count % sizeof(elf_fpreg_t) == 0',
+ * which is supposed to have been guaranteed by the kernel before
+ * calling us, e.g. in `ptrace_regset'. We enforce that requirement,
+ * so that we can safely avoid preinitializing temporaries for
+ * partial register writes.
+ */
static int fpr_set(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
const void *kbuf, const void __user *ubuf)
{
- unsigned i;
+ const int fcr31_pos = NUM_FPU_REGS * sizeof(elf_fpreg_t);
+ u32 fcr31;
int err;
- u64 fpr_val;
- /* XXX fcr31 */
+ BUG_ON(count % sizeof(elf_fpreg_t));
+
+ if (pos + count > sizeof(elf_fpregset_t))
+ return -EIO;
init_fp_ctx(target);
- if (sizeof(target->thread.fpu.fpr[i]) == sizeof(elf_fpreg_t))
- return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
- &target->thread.fpu,
- 0, sizeof(elf_fpregset_t));
+ if (sizeof(target->thread.fpu.fpr[0]) == sizeof(elf_fpreg_t))
+ err = fpr_set_fpa(target, &pos, &count, &kbuf, &ubuf);
+ else
+ err = fpr_set_msa(target, &pos, &count, &kbuf, &ubuf);
+ if (err)
+ return err;
- BUILD_BUG_ON(sizeof(fpr_val) != sizeof(elf_fpreg_t));
- for (i = 0; i < NUM_FPU_REGS && count >= sizeof(elf_fpreg_t); i++) {
+ if (count > 0) {
err = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
- &fpr_val, i * sizeof(elf_fpreg_t),
- (i + 1) * sizeof(elf_fpreg_t));
+ &fcr31,
+ fcr31_pos, fcr31_pos + sizeof(u32));
if (err)
return err;
- set_fpr64(&target->thread.fpu.fpr[i], 0, fpr_val);
+
+ ptrace_setfcr31(target, fcr31);
}
- return 0;
+ return err;
}
enum mips_regset {