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authorAl Viro <viro@zeniv.linux.org.uk>2020-02-18 20:14:34 +0300
committerAl Viro <viro@zeniv.linux.org.uk>2020-07-27 21:31:07 +0300
commit0557d64d983e3dedead2d4b4e8abc49620d5f5d2 (patch)
tree443afb37b0f11b5a72ae574b5b19ea234a0074e5 /arch/x86/math-emu
parent7717cb9bdd0421faa432a4e0d499fdba6e2394c8 (diff)
downloadlinux-0557d64d983e3dedead2d4b4e8abc49620d5f5d2.tar.xz
x86: switch to ->regset_get()
All instances of ->get() in arch/x86 switched; that might or might not be worth splitting up. Notes: * for xstateregs_get() the amount we want to store is determined at the boot time; see init_xstate_size() and update_regset_xstate_info() for details. task->thread.fpu.state.xsave ends with a flexible array member and the amount of data in it depends upon the FPU features supported/enabled. * fpregs_get() writes slightly less than full ->thread.fpu.state.fsave (the last word is not copied); we pass the full size of state.fsave and let membuf_write() trim to the amount declared by regset - __regset_get() will make sure that the space in buffer is no more than that. * copy_xstate_to_user() and its helpers are gone now. * fpregs_soft_get() was getting user_regset_copyout() arguments wrong. Since "x86: x86 user_regset math_emu" back in 2008... I really doubt that it's worth splitting out for -stable, though - you need a 486SX box for that to trigger... [Kevin's braino fix for copy_xstate_to_kernel() essentially duplicated here] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'arch/x86/math-emu')
-rw-r--r--arch/x86/math-emu/fpu_entry.c19
1 files changed, 5 insertions, 14 deletions
diff --git a/arch/x86/math-emu/fpu_entry.c b/arch/x86/math-emu/fpu_entry.c
index a873da6b46d6..8679a9d6c47f 100644
--- a/arch/x86/math-emu/fpu_entry.c
+++ b/arch/x86/math-emu/fpu_entry.c
@@ -689,12 +689,10 @@ int fpregs_soft_set(struct task_struct *target,
int fpregs_soft_get(struct task_struct *target,
const struct user_regset *regset,
- unsigned int pos, unsigned int count,
- void *kbuf, void __user *ubuf)
+ struct membuf to)
{
struct swregs_state *s387 = &target->thread.fpu.state.soft;
const void *space = s387->st_space;
- int ret;
int offset = (S387->ftop & 7) * 10, other = 80 - offset;
RE_ENTRANT_CHECK_OFF;
@@ -709,18 +707,11 @@ int fpregs_soft_get(struct task_struct *target,
S387->fos |= 0xffff0000;
#endif /* PECULIAR_486 */
- ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, s387, 0,
- offsetof(struct swregs_state, st_space));
-
- /* Copy all registers in stack order. */
- if (!ret)
- ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
- space + offset, 0, other);
- if (!ret)
- ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
- space, 0, offset);
+ membuf_write(&to, s387, offsetof(struct swregs_state, st_space));
+ membuf_write(&to, space + offset, other);
+ membuf_write(&to, space, offset);
RE_ENTRANT_CHECK_ON;
- return ret;
+ return 0;
}