x86/fpu/xstate: Use fpstate for copy_uabi_to_xstate()

Prepare for dynamically enabled states per task. The function needs to
retrieve the features and sizes which are valid in a fpstate
context. Retrieve them from fpstate.

Move the function declarations to the core header as they are not
required anywhere else.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20211013145323.233529986@linutronix.de

diff --git a/arch/x86/include/asm/fpu/xstate.h b/arch/x86/include/asm/fpu/xstate.h
index fb329bb..61fcb15 100644 (file)
--- a/arch/x86/include/asm/fpu/xstate.h
+++ b/arch/x86/include/asm/fpu/xstate.h
@@ -129,20 +129,8 @@ extern void __init update_regset_xstate_info(unsigned int size,
                                             u64 xstate_mask);
 
 int xfeature_size(int xfeature_nr);
-int copy_uabi_from_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf);
-int copy_sigframe_from_user_to_xstate(struct xregs_state *xsave, const void __user *ubuf);
 
 void xsaves(struct xregs_state *xsave, u64 mask);
 void xrstors(struct xregs_state *xsave, u64 mask);
 
-enum xstate_copy_mode {
-       XSTATE_COPY_FP,
-       XSTATE_COPY_FX,
-       XSTATE_COPY_XSAVE,
-};
-
-struct membuf;
-void copy_xstate_to_uabi_buf(struct membuf to, struct task_struct *tsk,
-                            enum xstate_copy_mode mode);
-
 #endif

diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c
index 04fef47..b497eca 100644 (file)
--- a/arch/x86/kernel/fpu/core.c
+++ b/arch/x86/kernel/fpu/core.c
@@ -222,7 +222,7 @@ int fpu_copy_kvm_uabi_to_fpstate(struct fpu *fpu, const void *buf, u64 xcr0,
        if (ustate->xsave.header.xfeatures & ~xcr0)
                return -EINVAL;
 
-       ret = copy_uabi_from_kernel_to_xstate(&kstate->regs.xsave, ustate);
+       ret = copy_uabi_from_kernel_to_xstate(kstate, ustate);
        if (ret)
                return ret;
 

diff --git a/arch/x86/kernel/fpu/regset.c b/arch/x86/kernel/fpu/regset.c
index ec77779..f8c485a 100644 (file)
--- a/arch/x86/kernel/fpu/regset.c
+++ b/arch/x86/kernel/fpu/regset.c
@@ -8,11 +8,11 @@
 #include <asm/fpu/api.h>
 #include <asm/fpu/signal.h>
 #include <asm/fpu/regset.h>
-#include <asm/fpu/xstate.h>
 
 #include "context.h"
 #include "internal.h"
 #include "legacy.h"
+#include "xstate.h"
 
 /*
  * The xstateregs_active() routine is the same as the regset_fpregs_active() routine,
@@ -168,8 +168,7 @@ int xstateregs_set(struct task_struct *target, const struct user_regset *regset,
        }
 
        fpu_force_restore(fpu);
-       ret = copy_uabi_from_kernel_to_xstate(&fpu->fpstate->regs.xsave,
-                                             kbuf ?: tmpbuf);
+       ret = copy_uabi_from_kernel_to_xstate(fpu->fpstate, kbuf ?: tmpbuf);
 
 out:
        vfree(tmpbuf);

diff --git a/arch/x86/kernel/fpu/signal.c b/arch/x86/kernel/fpu/signal.c
index 5aca418..935818b 100644 (file)
--- a/arch/x86/kernel/fpu/signal.c
+++ b/arch/x86/kernel/fpu/signal.c
@@ -375,7 +375,7 @@ static bool __fpu_restore_sig(void __user *buf, void __user *buf_fx,
 
        fpregs = &fpu->fpstate->regs;
        if (use_xsave() && !fx_only) {
-               if (copy_sigframe_from_user_to_xstate(&fpregs->xsave, buf_fx))
+               if (copy_sigframe_from_user_to_xstate(fpu->fpstate, buf_fx))
                        return false;
        } else {
                if (__copy_from_user(&fpregs->fxsave, buf_fx,

diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
index 54cc0a4..4cfd3bc 100644 (file)
--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c
@@ -463,10 +463,11 @@ int xfeature_size(int xfeature_nr)
 }
 
 /* Validate an xstate header supplied by userspace (ptrace or sigreturn) */
-static int validate_user_xstate_header(const struct xstate_header *hdr)
+static int validate_user_xstate_header(const struct xstate_header *hdr,
+                                      struct fpstate *fpstate)
 {
        /* No unknown or supervisor features may be set */
-       if (hdr->xfeatures & ~xfeatures_mask_uabi())
+       if (hdr->xfeatures & ~fpstate->user_xfeatures)
                return -EINVAL;
 
        /* Userspace must use the uncompacted format */
@@ -1115,9 +1116,10 @@ static int copy_from_buffer(void *dst, unsigned int offset, unsigned int size,
 }
 
 
-static int copy_uabi_to_xstate(struct xregs_state *xsave, const void *kbuf,
+static int copy_uabi_to_xstate(struct fpstate *fpstate, const void *kbuf,
                               const void __user *ubuf)
 {
+       struct xregs_state *xsave = &fpstate->regs.xsave;
        unsigned int offset, size;
        struct xstate_header hdr;
        u64 mask;
@@ -1127,7 +1129,7 @@ static int copy_uabi_to_xstate(struct xregs_state *xsave, const void *kbuf,
        if (copy_from_buffer(&hdr, offset, sizeof(hdr), kbuf, ubuf))
                return -EFAULT;
 
-       if (validate_user_xstate_header(&hdr))
+       if (validate_user_xstate_header(&hdr, fpstate))
                return -EINVAL;
 
        /* Validate MXCSR when any of the related features is in use */
@@ -1182,9 +1184,9 @@ static int copy_uabi_to_xstate(struct xregs_state *xsave, const void *kbuf,
  * Convert from a ptrace standard-format kernel buffer to kernel XSAVE[S]
  * format and copy to the target thread. Used by ptrace and KVM.
  */
-int copy_uabi_from_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf)
+int copy_uabi_from_kernel_to_xstate(struct fpstate *fpstate, const void *kbuf)
 {
-       return copy_uabi_to_xstate(xsave, kbuf, NULL);
+       return copy_uabi_to_xstate(fpstate, kbuf, NULL);
 }
 
 /*
@@ -1192,10 +1194,10 @@ int copy_uabi_from_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf)
  * XSAVE[S] format and copy to the target thread. This is called from the
  * sigreturn() and rt_sigreturn() system calls.
  */
-int copy_sigframe_from_user_to_xstate(struct xregs_state *xsave,
+int copy_sigframe_from_user_to_xstate(struct fpstate *fpstate,
                                      const void __user *ubuf)
 {
-       return copy_uabi_to_xstate(xsave, NULL, ubuf);
+       return copy_uabi_to_xstate(fpstate, NULL, ubuf);
 }
 
 static bool validate_independent_components(u64 mask)

diff --git a/arch/x86/kernel/fpu/xstate.h b/arch/x86/kernel/fpu/xstate.h
index b74c595..379dbfa 100644 (file)
--- a/arch/x86/kernel/fpu/xstate.h
+++ b/arch/x86/kernel/fpu/xstate.h
@@ -15,8 +15,20 @@ static inline void xstate_init_xcomp_bv(struct xregs_state *xsave, u64 mask)
                xsave->header.xcomp_bv = mask | XCOMP_BV_COMPACTED_FORMAT;
 }
 
+enum xstate_copy_mode {
+       XSTATE_COPY_FP,
+       XSTATE_COPY_FX,
+       XSTATE_COPY_XSAVE,
+};
+
+struct membuf;
 extern void __copy_xstate_to_uabi_buf(struct membuf to, struct fpstate *fpstate,
                                      u32 pkru_val, enum xstate_copy_mode copy_mode);
+extern void copy_xstate_to_uabi_buf(struct membuf to, struct task_struct *tsk,
+                                   enum xstate_copy_mode mode);
+extern int copy_uabi_from_kernel_to_xstate(struct fpstate *fpstate, const void *kbuf);
+extern int copy_sigframe_from_user_to_xstate(struct fpstate *fpstate, const void __user *ubuf);
+
 
 extern void fpu__init_cpu_xstate(void);
 extern void fpu__init_system_xstate(void);