[PATCH v9 02/26] x86/fpu/xstate: Modify state copy helpers to handle both static and dynamic buffers

Chang S. Bae
2021-07-30T15:06:48Z

Have all the functions copying XSTATE take a struct fpu * pointer in
preparation for dynamic state buffer support.

No functional change.

Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Reviewed-by: Len Brown <len.brown@intel.com>
Cc: x86@kernel.org
Cc: linux-kernel@vger.kernel.org
---
Changes from v5:
* Adjusted function prototype changes to the recent renamed on the new
base.

Changes from v3:
* Updated the changelog. (Borislav Petkov)

Changes from v2:
* Updated the changelog with task->fpu removed. (Borislav Petkov)
---
arch/x86/include/asm/fpu/xstate.h | 4 ++--
arch/x86/kernel/fpu/regset.c | 2 +-
arch/x86/kernel/fpu/signal.c | 2 +-
arch/x86/kernel/fpu/xstate.c | 12 ++++++------
4 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/arch/x86/include/asm/fpu/xstate.h b/arch/x86/include/asm/fpu/xstate.h
index 109dfcc75299..ede166e9d3f2 100644
--- a/arch/x86/include/asm/fpu/xstate.h
+++ b/arch/x86/include/asm/fpu/xstate.h
@@ -136,8 +136,8 @@ extern void __init update_regset_xstate_info(unsigned int size,

void *get_xsave_addr(struct xregs_state *xsave, int xfeature_nr);
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);
+int copy_uabi_from_kernel_to_xstate(struct fpu *fpu, const void *kbuf);
+int copy_sigframe_from_user_to_xstate(struct fpu *fpu, const void __user *ubuf);

void xsaves(struct xregs_state *xsave, u64 mask);
void xrstors(struct xregs_state *xsave, u64 mask);
diff --git a/arch/x86/kernel/fpu/regset.c b/arch/x86/kernel/fpu/regset.c
index 66ed317ebc0d..49dd307003ec 100644
--- a/arch/x86/kernel/fpu/regset.c
+++ b/arch/x86/kernel/fpu/regset.c
@@ -164,7 +164,7 @@ int xstateregs_set(struct task_struct *target, const struct user_regset *regset,
}

fpu_force_restore(fpu);
- ret = copy_uabi_from_kernel_to_xstate(&fpu->state.xsave, kbuf ?: tmpbuf);
+ ret = copy_uabi_from_kernel_to_xstate(fpu, kbuf ?: tmpbuf);

out:
vfree(tmpbuf);
diff --git a/arch/x86/kernel/fpu/signal.c b/arch/x86/kernel/fpu/signal.c
index 445c57c9c539..bec8c8046888 100644
--- a/arch/x86/kernel/fpu/signal.c
+++ b/arch/x86/kernel/fpu/signal.c
@@ -371,7 +371,7 @@ static int __fpu_restore_sig(void __user *buf, void __user *buf_fx,
fpregs_unlock();

if (use_xsave() && !fx_only) {
- ret = copy_sigframe_from_user_to_xstate(&fpu->state.xsave, buf_fx);
+ ret = copy_sigframe_from_user_to_xstate(fpu, buf_fx);
if (ret)
return ret;
} else {
diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
index d4fdceb9a309..59f08953201c 100644
--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c
@@ -1089,10 +1089,10 @@ static int copy_from_buffer(void *dst, unsigned int offset, unsigned int size,
return 0;
}

-
-static int copy_uabi_to_xstate(struct xregs_state *xsave, const void *kbuf,
+static int copy_uabi_to_xstate(struct fpu *fpu, const void *kbuf,
const void __user *ubuf)
{
+ struct xregs_state *xsave = &fpu->state.xsave;
unsigned int offset, size;
struct xstate_header hdr;
u64 mask;
@@ -1158,9 +1158,9 @@ static int copy_uabi_to_xstate(struct xregs_state *xsave, const void *kbuf,
* format and copy to the target thread. This is called from
* xstateregs_set().
*/
-int copy_uabi_from_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf)
+int copy_uabi_from_kernel_to_xstate(struct fpu *fpu, const void *kbuf)
{
- return copy_uabi_to_xstate(xsave, kbuf, NULL);
+ return copy_uabi_to_xstate(fpu, kbuf, NULL);
}

/*
@@ -1168,10 +1168,10 @@ 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 fpu *fpu,
const void __user *ubuf)
{
- return copy_uabi_to_xstate(xsave, NULL, ubuf);
+ return copy_uabi_to_xstate(fpu, NULL, ubuf);
}

static bool validate_xsaves_xrstors(u64 mask)
--
2.17.1