uml: ptrace floating point fixes

Handle floating point state better in ptrace.  The code now correctly
distinguishes between PTRACE_[GS]ETFPREGS and PTRACE_[GS]ETFPXREGS.  The FPX
requests get handed off to arch-specific code because that's not generic.

get_fpregs, set_fpregs, set_fpregs, and set_fpxregs needed real
implementations.

Something here exposed a missing include in asm/page.h, which needed
linux/types.h in order to get gfp_t, so that's fixed here.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 39 insertions, 14 deletions

diff --git a/arch/um/sys-x86_64/ptrace.c b/arch/um/sys-x86_64/ptrace.c
index 1970d78aa52..b9032992a99 100644
--- a/arch/um/sys-x86_64/ptrace.c
+++ b/arch/um/sys-x86_64/ptrace.c
@@ -156,28 +156,53 @@ int is_syscall(unsigned long addr)
         return(instr == 0x050f);
 }
 
-int get_fpregs(unsigned long buf, struct task_struct *child)
+int get_fpregs(struct user_i387_struct __user *buf, struct task_struct *child)
 {
-        panic("get_fpregs");
-        return(0);
-}
+        int err, n, cpu = ((struct thread_info *) child->stack)->cpu;
+        long fpregs[HOST_FP_SIZE];
 
-int set_fpregs(unsigned long buf, struct task_struct *child)
-{
-        panic("set_fpregs");
-        return(0);
+        BUG_ON(sizeof(*buf) != sizeof(fpregs));
+        err = save_fp_registers(userspace_pid[cpu], fpregs);
+        if (err)
+                return err;
+
+        n = copy_to_user((void *) buf, fpregs, sizeof(fpregs));
+        if(n > 0)
+                return -EFAULT;
+
+        return n;
 }
 
-int get_fpxregs(unsigned long buf, struct task_struct *tsk)
+int set_fpregs(struct user_i387_struct __user *buf, struct task_struct *child)
 {
-        panic("get_fpxregs");
-        return(0);
+        int n, cpu = ((struct thread_info *) child->stack)->cpu;
+        long fpregs[HOST_FP_SIZE];
+
+        BUG_ON(sizeof(*buf) != sizeof(fpregs));
+        n = copy_from_user(fpregs, (void *) buf, sizeof(fpregs));
+        if (n > 0)
+                return -EFAULT;
+
+        return restore_fp_registers(userspace_pid[cpu], fpregs);
 }
 
-int set_fpxregs(unsigned long buf, struct task_struct *tsk)
+long subarch_ptrace(struct task_struct *child, long request, long addr,
+                    long data)
 {
-        panic("set_fxpregs");
-        return(0);
+        int ret = -EIO;
+
+        switch (request) {
+        case PTRACE_GETFPXREGS: /* Get the child FPU state. */
+                ret = get_fpregs((struct user_i387_struct __user *) data,
+                                 child);
+                break;
+        case PTRACE_SETFPXREGS: /* Set the child FPU state. */
+                ret = set_fpregs((struct user_i387_struct __user *) data,
+                                 child);
+                break;
+        }
+
+        return ret;
 }
 
 /*