1// SPDX-License-Identifier: GPL-2.0
2/* linux/arch/sparc/kernel/sys_sparc.c
3 *
4 * This file contains various random system calls that
5 * have a non-standard calling sequence on the Linux/sparc
6 * platform.
7 */
8
9#include <linux/errno.h>
10#include <linux/types.h>
11#include <linux/sched/signal.h>
12#include <linux/sched/mm.h>
13#include <linux/sched/debug.h>
14#include <linux/mm.h>
15#include <linux/fs.h>
16#include <linux/file.h>
17#include <linux/sem.h>
18#include <linux/msg.h>
19#include <linux/shm.h>
20#include <linux/stat.h>
21#include <linux/syscalls.h>
22#include <linux/mman.h>
23#include <linux/utsname.h>
24#include <linux/smp.h>
25#include <linux/ipc.h>
26
27#include <linux/uaccess.h>
28#include <asm/unistd.h>
29
30#include "systbls.h"
31
32/* #define DEBUG_UNIMP_SYSCALL */
33
34/* XXX Make this per-binary type, this way we can detect the type of
35 * XXX a binary.  Every Sparc executable calls this very early on.
36 */
37SYSCALL_DEFINE0(getpagesize)
38{
39	return PAGE_SIZE; /* Possibly older binaries want 8192 on sun4's? */
40}
41
42unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags)
43{
44	struct vm_unmapped_area_info info;
45
46	if (flags & MAP_FIXED) {
47		/* We do not accept a shared mapping if it would violate
48		 * cache aliasing constraints.
49		 */
50		if ((flags & MAP_SHARED) &&
51		    ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
52			return -EINVAL;
53		return addr;
54	}
55
56	/* See asm-sparc/uaccess.h */
57	if (len > TASK_SIZE - PAGE_SIZE)
58		return -ENOMEM;
59	if (!addr)
60		addr = TASK_UNMAPPED_BASE;
61
62	info.flags = 0;
63	info.length = len;
64	info.low_limit = addr;
65	info.high_limit = TASK_SIZE;
66	info.align_mask = (flags & MAP_SHARED) ?
67		(PAGE_MASK & (SHMLBA - 1)) : 0;
68	info.align_offset = pgoff << PAGE_SHIFT;
69	return vm_unmapped_area(&info);
70}
71
72/*
73 * sys_pipe() is the normal C calling standard for creating
74 * a pipe. It's not the way unix traditionally does this, though.
75 */
76SYSCALL_DEFINE0(sparc_pipe)
77{
78	int fd[2];
79	int error;
80
81	error = do_pipe_flags(fd, 0);
82	if (error)
83		goto out;
84	current_pt_regs()->u_regs[UREG_I1] = fd[1];
85	error = fd[0];
86out:
87	return error;
88}
89
90int sparc_mmap_check(unsigned long addr, unsigned long len)
91{
92	/* See asm-sparc/uaccess.h */
93	if (len > TASK_SIZE - PAGE_SIZE || addr + len > TASK_SIZE - PAGE_SIZE)
94		return -EINVAL;
95
96	return 0;
97}
98
99/* Linux version of mmap */
100
101SYSCALL_DEFINE6(mmap2, unsigned long, addr, unsigned long, len,
102	unsigned long, prot, unsigned long, flags, unsigned long, fd,
103	unsigned long, pgoff)
104{
105	/* Make sure the shift for mmap2 is constant (12), no matter what PAGE_SIZE
106	   we have. */
107	return ksys_mmap_pgoff(addr, len, prot, flags, fd,
108			       pgoff >> (PAGE_SHIFT - 12));
109}
110
111SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len,
112	unsigned long, prot, unsigned long, flags, unsigned long, fd,
113	unsigned long, off)
114{
115	/* no alignment check? */
116	return ksys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
117}
118
119SYSCALL_DEFINE5(sparc_remap_file_pages, unsigned long, start, unsigned long, size,
120			   unsigned long, prot, unsigned long, pgoff,
121			   unsigned long, flags)
122{
123	/* This works on an existing mmap so we don't need to validate
124	 * the range as that was done at the original mmap call.
125	 */
126	return sys_remap_file_pages(start, size, prot,
127				    (pgoff >> (PAGE_SHIFT - 12)), flags);
128}
129
130SYSCALL_DEFINE0(nis_syscall)
131{
132	static int count = 0;
133	struct pt_regs *regs = current_pt_regs();
134
135	if (count++ > 5)
136		return -ENOSYS;
137	printk ("%s[%d]: Unimplemented SPARC system call %d\n",
138		current->comm, task_pid_nr(current), (int)regs->u_regs[1]);
139#ifdef DEBUG_UNIMP_SYSCALL
140	show_regs (regs);
141#endif
142	return -ENOSYS;
143}
144
145/* #define DEBUG_SPARC_BREAKPOINT */
146
147asmlinkage void
148sparc_breakpoint (struct pt_regs *regs)
149{
150
151#ifdef DEBUG_SPARC_BREAKPOINT
152        printk ("TRAP: Entering kernel PC=%x, nPC=%x\n", regs->pc, regs->npc);
153#endif
154	force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->pc);
155
156#ifdef DEBUG_SPARC_BREAKPOINT
157	printk ("TRAP: Returning to space: PC=%x nPC=%x\n", regs->pc, regs->npc);
158#endif
159}
160
161SYSCALL_DEFINE3(sparc_sigaction, int, sig,
162		struct old_sigaction __user *,act,
163		struct old_sigaction __user *,oact)
164{
165	WARN_ON_ONCE(sig >= 0);
166	return sys_sigaction(-sig, act, oact);
167}
168
169SYSCALL_DEFINE5(rt_sigaction, int, sig,
170		 const struct sigaction __user *, act,
171		 struct sigaction __user *, oact,
172		 void __user *, restorer,
173		 size_t, sigsetsize)
174{
175	struct k_sigaction new_ka, old_ka;
176	int ret;
177
178	/* XXX: Don't preclude handling different sized sigset_t's.  */
179	if (sigsetsize != sizeof(sigset_t))
180		return -EINVAL;
181
182	if (act) {
183		new_ka.ka_restorer = restorer;
184		if (copy_from_user(&new_ka.sa, act, sizeof(*act)))
185			return -EFAULT;
186	}
187
188	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
189
190	if (!ret && oact) {
191		if (copy_to_user(oact, &old_ka.sa, sizeof(*oact)))
192			return -EFAULT;
193	}
194
195	return ret;
196}
197
198SYSCALL_DEFINE2(getdomainname, char __user *, name, int, len)
199{
200	int nlen, err;
201	char tmp[__NEW_UTS_LEN + 1];
202
203	if (len < 0)
204		return -EINVAL;
205
206	down_read(&uts_sem);
207
208	nlen = strlen(utsname()->domainname) + 1;
209	err = -EINVAL;
210	if (nlen > len)
211		goto out_unlock;
212	memcpy(tmp, utsname()->domainname, nlen);
213
214	up_read(&uts_sem);
215
216	if (copy_to_user(name, tmp, nlen))
217		return -EFAULT;
218	return 0;
219
220out_unlock:
221	up_read(&uts_sem);
222	return err;
223}
224