Commit | Line | Data |
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caab277b | 1 | // SPDX-License-Identifier: GPL-2.0-only |
3dd681d9 WD |
2 | /* |
3 | * Based on arch/arm/kernel/sys_arm.c | |
4 | * | |
5 | * Copyright (C) People who wrote linux/arch/i386/kernel/sys_i386.c | |
6 | * Copyright (C) 1995, 1996 Russell King. | |
7 | * Copyright (C) 2012 ARM Ltd. | |
3dd681d9 WD |
8 | */ |
9 | ||
3dd681d9 | 10 | #include <linux/compat.h> |
222fc0c8 | 11 | #include <linux/cpufeature.h> |
3dd681d9 WD |
12 | #include <linux/personality.h> |
13 | #include <linux/sched.h> | |
f361bf4a | 14 | #include <linux/sched/signal.h> |
3dd681d9 WD |
15 | #include <linux/slab.h> |
16 | #include <linux/syscalls.h> | |
17 | #include <linux/uaccess.h> | |
18 | ||
19 | #include <asm/cacheflush.h> | |
532826f3 | 20 | #include <asm/system_misc.h> |
222fc0c8 | 21 | #include <asm/tlbflush.h> |
f3e5c847 | 22 | #include <asm/unistd.h> |
3dd681d9 | 23 | |
a2d25a53 VM |
24 | static long |
25 | __do_compat_cache_op(unsigned long start, unsigned long end) | |
3dd681d9 | 26 | { |
a2d25a53 | 27 | long ret; |
3dd681d9 | 28 | |
a2d25a53 VM |
29 | do { |
30 | unsigned long chunk = min(PAGE_SIZE, end - start); | |
3dd681d9 | 31 | |
a2d25a53 VM |
32 | if (fatal_signal_pending(current)) |
33 | return 0; | |
34 | ||
222fc0c8 JM |
35 | if (cpus_have_const_cap(ARM64_WORKAROUND_1542419)) { |
36 | /* | |
37 | * The workaround requires an inner-shareable tlbi. | |
38 | * We pick the reserved-ASID to minimise the impact. | |
39 | */ | |
27a22fbd | 40 | __tlbi(aside1is, __TLBI_VADDR(0, 0)); |
222fc0c8 JM |
41 | dsb(ish); |
42 | } | |
43 | ||
a2d25a53 VM |
44 | ret = __flush_cache_user_range(start, start + chunk); |
45 | if (ret) | |
46 | return ret; | |
47 | ||
48 | cond_resched(); | |
49 | start += chunk; | |
50 | } while (start < end); | |
51 | ||
52 | return 0; | |
3dd681d9 WD |
53 | } |
54 | ||
a2d25a53 VM |
55 | static inline long |
56 | do_compat_cache_op(unsigned long start, unsigned long end, int flags) | |
57 | { | |
58 | if (end < start || flags) | |
59 | return -EINVAL; | |
60 | ||
96d4f267 | 61 | if (!access_ok((const void __user *)start, end - start)) |
a2d25a53 VM |
62 | return -EFAULT; |
63 | ||
64 | return __do_compat_cache_op(start, end); | |
65 | } | |
3dd681d9 WD |
66 | /* |
67 | * Handle all unrecognised system calls. | |
68 | */ | |
53290432 | 69 | long compat_arm_syscall(struct pt_regs *regs, int scno) |
3dd681d9 | 70 | { |
6fa998e8 | 71 | void __user *addr; |
3dd681d9 | 72 | |
53290432 | 73 | switch (scno) { |
3dd681d9 WD |
74 | /* |
75 | * Flush a region from virtual address 'r0' to virtual address 'r1' | |
76 | * _exclusive_. There is no alignment requirement on either address; | |
77 | * user space does not need to know the hardware cache layout. | |
78 | * | |
79 | * r2 contains flags. It should ALWAYS be passed as ZERO until it | |
80 | * is defined to be something else. For now we ignore it, but may | |
81 | * the fires of hell burn in your belly if you break this rule. ;) | |
82 | * | |
83 | * (at a later date, we may want to allow this call to not flush | |
84 | * various aspects of the cache. Passing '0' will guarantee that | |
85 | * everything necessary gets flushed to maintain consistency in | |
86 | * the specified region). | |
87 | */ | |
88 | case __ARM_NR_compat_cacheflush: | |
a2d25a53 | 89 | return do_compat_cache_op(regs->regs[0], regs->regs[1], regs->regs[2]); |
3dd681d9 WD |
90 | |
91 | case __ARM_NR_compat_set_tls: | |
65896545 | 92 | current->thread.uw.tp_value = regs->regs[0]; |
eb35bdd7 WD |
93 | |
94 | /* | |
95 | * Protect against register corruption from context switch. | |
96 | * See comment in tls_thread_flush. | |
97 | */ | |
98 | barrier(); | |
adf75899 | 99 | write_sysreg(regs->regs[0], tpidrro_el0); |
3dd681d9 WD |
100 | return 0; |
101 | ||
102 | default: | |
532826f3 | 103 | /* |
169113ec | 104 | * Calls 0xf0xxx..0xf07ff are defined to return -ENOSYS |
532826f3 MW |
105 | * if not implemented, rather than raising SIGILL. This |
106 | * way the calling program can gracefully determine whether | |
107 | * a feature is supported. | |
108 | */ | |
53290432 | 109 | if (scno < __ARM_NR_COMPAT_END) |
532826f3 MW |
110 | return -ENOSYS; |
111 | break; | |
3dd681d9 | 112 | } |
532826f3 | 113 | |
6fa998e8 EB |
114 | addr = (void __user *)instruction_pointer(regs) - |
115 | (compat_thumb_mode(regs) ? 2 : 4); | |
532826f3 | 116 | |
6fa998e8 | 117 | arm64_notify_die("Oops - bad compat syscall(2)", regs, |
53290432 | 118 | SIGILL, ILL_ILLTRP, addr, scno); |
532826f3 | 119 | return 0; |
3dd681d9 | 120 | } |