1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/kernel.h>
3 #include <linux/types.h>
4 #include <linux/thread_info.h>
5 #include <linux/uaccess.h>
6 #include <linux/sched.h>
7 
8 #include <asm/sigcontext.h>
9 #include <asm/fpumacro.h>
10 #include <asm/ptrace.h>
11 #include <asm/switch_to.h>
12 
13 #include "sigutil.h"
14 
save_fpu_state(struct pt_regs * regs,__siginfo_fpu_t __user * fpu)15 int save_fpu_state(struct pt_regs *regs, __siginfo_fpu_t __user *fpu)
16 {
17 	int err = 0;
18 #ifdef CONFIG_SMP
19 	if (test_tsk_thread_flag(current, TIF_USEDFPU)) {
20 		put_psr(get_psr() | PSR_EF);
21 		fpsave(&current->thread.float_regs[0], &current->thread.fsr,
22 		       &current->thread.fpqueue[0], &current->thread.fpqdepth);
23 		regs->psr &= ~(PSR_EF);
24 		clear_tsk_thread_flag(current, TIF_USEDFPU);
25 	}
26 #else
27 	if (current == last_task_used_math) {
28 		put_psr(get_psr() | PSR_EF);
29 		fpsave(&current->thread.float_regs[0], &current->thread.fsr,
30 		       &current->thread.fpqueue[0], &current->thread.fpqdepth);
31 		last_task_used_math = NULL;
32 		regs->psr &= ~(PSR_EF);
33 	}
34 #endif
35 	err |= __copy_to_user(&fpu->si_float_regs[0],
36 			      &current->thread.float_regs[0],
37 			      (sizeof(unsigned long) * 32));
38 	err |= __put_user(current->thread.fsr, &fpu->si_fsr);
39 	err |= __put_user(current->thread.fpqdepth, &fpu->si_fpqdepth);
40 	if (current->thread.fpqdepth != 0)
41 		err |= __copy_to_user(&fpu->si_fpqueue[0],
42 				      &current->thread.fpqueue[0],
43 				      ((sizeof(unsigned long) +
44 				      (sizeof(unsigned long *)))*16));
45 	clear_used_math();
46 	return err;
47 }
48 
restore_fpu_state(struct pt_regs * regs,__siginfo_fpu_t __user * fpu)49 int restore_fpu_state(struct pt_regs *regs, __siginfo_fpu_t __user *fpu)
50 {
51 	int err;
52 
53 	if (((unsigned long) fpu) & 3)
54 		return -EFAULT;
55 
56 #ifdef CONFIG_SMP
57 	if (test_tsk_thread_flag(current, TIF_USEDFPU))
58 		regs->psr &= ~PSR_EF;
59 #else
60 	if (current == last_task_used_math) {
61 		last_task_used_math = NULL;
62 		regs->psr &= ~PSR_EF;
63 	}
64 #endif
65 	set_used_math();
66 	clear_tsk_thread_flag(current, TIF_USEDFPU);
67 
68 	if (!access_ok(fpu, sizeof(*fpu)))
69 		return -EFAULT;
70 
71 	err = __copy_from_user(&current->thread.float_regs[0], &fpu->si_float_regs[0],
72 			       (sizeof(unsigned long) * 32));
73 	err |= __get_user(current->thread.fsr, &fpu->si_fsr);
74 	err |= __get_user(current->thread.fpqdepth, &fpu->si_fpqdepth);
75 	if (current->thread.fpqdepth != 0)
76 		err |= __copy_from_user(&current->thread.fpqueue[0],
77 					&fpu->si_fpqueue[0],
78 					((sizeof(unsigned long) +
79 					(sizeof(unsigned long *)))*16));
80 	return err;
81 }
82 
save_rwin_state(int wsaved,__siginfo_rwin_t __user * rwin)83 int save_rwin_state(int wsaved, __siginfo_rwin_t __user *rwin)
84 {
85 	int i, err = __put_user(wsaved, &rwin->wsaved);
86 
87 	for (i = 0; i < wsaved; i++) {
88 		struct reg_window32 *rp;
89 		unsigned long fp;
90 
91 		rp = &current_thread_info()->reg_window[i];
92 		fp = current_thread_info()->rwbuf_stkptrs[i];
93 		err |= copy_to_user(&rwin->reg_window[i], rp,
94 				    sizeof(struct reg_window32));
95 		err |= __put_user(fp, &rwin->rwbuf_stkptrs[i]);
96 	}
97 	return err;
98 }
99 
restore_rwin_state(__siginfo_rwin_t __user * rp)100 int restore_rwin_state(__siginfo_rwin_t __user *rp)
101 {
102 	struct thread_info *t = current_thread_info();
103 	int i, wsaved, err;
104 
105 	if (((unsigned long) rp) & 3)
106 		return -EFAULT;
107 
108 	get_user(wsaved, &rp->wsaved);
109 	if (wsaved > NSWINS)
110 		return -EFAULT;
111 
112 	err = 0;
113 	for (i = 0; i < wsaved; i++) {
114 		err |= copy_from_user(&t->reg_window[i],
115 				      &rp->reg_window[i],
116 				      sizeof(struct reg_window32));
117 		err |= __get_user(t->rwbuf_stkptrs[i],
118 				  &rp->rwbuf_stkptrs[i]);
119 	}
120 	if (err)
121 		return err;
122 
123 	t->w_saved = wsaved;
124 	synchronize_user_stack();
125 	if (t->w_saved)
126 		return -EFAULT;
127 	return 0;
128 
129 }
130