x86/fpu: Use 'struct fpu' in fpu__unlazy_stopped()

Migrate this function to pure 'struct fpu' usage.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c
index 183e69d..e3e8585 100644 (file)
--- a/arch/x86/kernel/fpu/core.c
+++ b/arch/x86/kernel/fpu/core.c
@@ -311,27 +311,26 @@ EXPORT_SYMBOL_GPL(fpstate_alloc_init);
  *       the read-only case, it's not strictly necessary for
  *       read-only access to the context.
  */
-static int fpu__unlazy_stopped(struct task_struct *child)
+static int fpu__unlazy_stopped(struct fpu *child_fpu)
 {
-       struct fpu *child_fpu = &child->thread.fpu;
        int ret;
 
-       if (WARN_ON_ONCE(child == current))
+       if (WARN_ON_ONCE(child_fpu == &current->thread.fpu))
                return -EINVAL;
 
        if (child_fpu->fpstate_active) {
-               child->thread.fpu.last_cpu = -1;
+               child_fpu->last_cpu = -1;
                return 0;
        }
 
        /*
         * Memory allocation at the first usage of the FPU and other state.
         */
-       ret = fpstate_alloc(&child->thread.fpu);
+       ret = fpstate_alloc(child_fpu);
        if (ret)
                return ret;
 
-       fpstate_init(&child->thread.fpu);
+       fpstate_init(child_fpu);
 
        /* Safe to do for stopped child tasks: */
        child_fpu->fpstate_active = 1;
@@ -426,12 +425,13 @@ int xfpregs_get(struct task_struct *target, const struct user_regset *regset,
                unsigned int pos, unsigned int count,
                void *kbuf, void __user *ubuf)
 {
+       struct fpu *fpu = &target->thread.fpu;
        int ret;
 
        if (!cpu_has_fxsr)
                return -ENODEV;
 
-       ret = fpu__unlazy_stopped(target);
+       ret = fpu__unlazy_stopped(fpu);
        if (ret)
                return ret;
 
@@ -445,12 +445,13 @@ int xfpregs_set(struct task_struct *target, const struct user_regset *regset,
                unsigned int pos, unsigned int count,
                const void *kbuf, const void __user *ubuf)
 {
+       struct fpu *fpu = &target->thread.fpu;
        int ret;
 
        if (!cpu_has_fxsr)
                return -ENODEV;
 
-       ret = fpu__unlazy_stopped(target);
+       ret = fpu__unlazy_stopped(fpu);
        if (ret)
                return ret;
 
@@ -478,13 +479,14 @@ int xstateregs_get(struct task_struct *target, const struct user_regset *regset,
                unsigned int pos, unsigned int count,
                void *kbuf, void __user *ubuf)
 {
+       struct fpu *fpu = &target->thread.fpu;
        struct xsave_struct *xsave;
        int ret;
 
        if (!cpu_has_xsave)
                return -ENODEV;
 
-       ret = fpu__unlazy_stopped(target);
+       ret = fpu__unlazy_stopped(fpu);
        if (ret)
                return ret;
 
@@ -508,13 +510,14 @@ int xstateregs_set(struct task_struct *target, const struct user_regset *regset,
                  unsigned int pos, unsigned int count,
                  const void *kbuf, const void __user *ubuf)
 {
+       struct fpu *fpu = &target->thread.fpu;
        struct xsave_struct *xsave;
        int ret;
 
        if (!cpu_has_xsave)
                return -ENODEV;
 
-       ret = fpu__unlazy_stopped(target);
+       ret = fpu__unlazy_stopped(fpu);
        if (ret)
                return ret;
 
@@ -674,10 +677,11 @@ int fpregs_get(struct task_struct *target, const struct user_regset *regset,
               unsigned int pos, unsigned int count,
               void *kbuf, void __user *ubuf)
 {
+       struct fpu *fpu = &target->thread.fpu;
        struct user_i387_ia32_struct env;
        int ret;
 
-       ret = fpu__unlazy_stopped(target);
+       ret = fpu__unlazy_stopped(fpu);
        if (ret)
                return ret;
 
@@ -705,10 +709,11 @@ int fpregs_set(struct task_struct *target, const struct user_regset *regset,
               unsigned int pos, unsigned int count,
               const void *kbuf, const void __user *ubuf)
 {
+       struct fpu *fpu = &target->thread.fpu;
        struct user_i387_ia32_struct env;
        int ret;
 
-       ret = fpu__unlazy_stopped(target);
+       ret = fpu__unlazy_stopped(fpu);
        if (ret)
                return ret;