xref: /linux/arch/sparc/kernel/sys_sparc_32.c (revision 249ebf3f65f8530beb2cbfb91bff1d83ba88d23c)
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  */
37 SYSCALL_DEFINE0(getpagesize)
38 {
39 	return PAGE_SIZE; /* Possibly older binaries want 8192 on sun4's? */
40 }
41 
42 unsigned 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.length = len;
63 	info.low_limit = addr;
64 	info.high_limit = TASK_SIZE;
65 	info.align_mask = (flags & MAP_SHARED) ?
66 		(PAGE_MASK & (SHMLBA - 1)) : 0;
67 	info.align_offset = pgoff << PAGE_SHIFT;
68 	return vm_unmapped_area(&info);
69 }
70 
71 /*
72  * sys_pipe() is the normal C calling standard for creating
73  * a pipe. It's not the way unix traditionally does this, though.
74  */
75 SYSCALL_DEFINE0(sparc_pipe)
76 {
77 	int fd[2];
78 	int error;
79 
80 	error = do_pipe_flags(fd, 0);
81 	if (error)
82 		goto out;
83 	current_pt_regs()->u_regs[UREG_I1] = fd[1];
84 	error = fd[0];
85 out:
86 	return error;
87 }
88 
89 int sparc_mmap_check(unsigned long addr, unsigned long len)
90 {
91 	/* See asm-sparc/uaccess.h */
92 	if (len > TASK_SIZE - PAGE_SIZE || addr + len > TASK_SIZE - PAGE_SIZE)
93 		return -EINVAL;
94 
95 	return 0;
96 }
97 
98 /* Linux version of mmap */
99 
100 SYSCALL_DEFINE6(mmap2, unsigned long, addr, unsigned long, len,
101 	unsigned long, prot, unsigned long, flags, unsigned long, fd,
102 	unsigned long, pgoff)
103 {
104 	/* Make sure the shift for mmap2 is constant (12), no matter what PAGE_SIZE
105 	   we have. */
106 	return ksys_mmap_pgoff(addr, len, prot, flags, fd,
107 			       pgoff >> (PAGE_SHIFT - 12));
108 }
109 
110 SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len,
111 	unsigned long, prot, unsigned long, flags, unsigned long, fd,
112 	unsigned long, off)
113 {
114 	/* no alignment check? */
115 	return ksys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
116 }
117 
118 SYSCALL_DEFINE5(sparc_remap_file_pages, unsigned long, start, unsigned long, size,
119 			   unsigned long, prot, unsigned long, pgoff,
120 			   unsigned long, flags)
121 {
122 	/* This works on an existing mmap so we don't need to validate
123 	 * the range as that was done at the original mmap call.
124 	 */
125 	return sys_remap_file_pages(start, size, prot,
126 				    (pgoff >> (PAGE_SHIFT - 12)), flags);
127 }
128 
129 SYSCALL_DEFINE0(nis_syscall)
130 {
131 	static int count = 0;
132 	struct pt_regs *regs = current_pt_regs();
133 
134 	if (count++ > 5)
135 		return -ENOSYS;
136 	printk ("%s[%d]: Unimplemented SPARC system call %d\n",
137 		current->comm, task_pid_nr(current), (int)regs->u_regs[1]);
138 #ifdef DEBUG_UNIMP_SYSCALL
139 	show_regs (regs);
140 #endif
141 	return -ENOSYS;
142 }
143 
144 /* #define DEBUG_SPARC_BREAKPOINT */
145 
146 asmlinkage void
147 sparc_breakpoint (struct pt_regs *regs)
148 {
149 
150 #ifdef DEBUG_SPARC_BREAKPOINT
151         printk ("TRAP: Entering kernel PC=%x, nPC=%x\n", regs->pc, regs->npc);
152 #endif
153 	force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->pc);
154 
155 #ifdef DEBUG_SPARC_BREAKPOINT
156 	printk ("TRAP: Returning to space: PC=%x nPC=%x\n", regs->pc, regs->npc);
157 #endif
158 }
159 
160 SYSCALL_DEFINE3(sparc_sigaction, int, sig,
161 		struct old_sigaction __user *,act,
162 		struct old_sigaction __user *,oact)
163 {
164 	WARN_ON_ONCE(sig >= 0);
165 	return sys_sigaction(-sig, act, oact);
166 }
167 
168 SYSCALL_DEFINE5(rt_sigaction, int, sig,
169 		 const struct sigaction __user *, act,
170 		 struct sigaction __user *, oact,
171 		 void __user *, restorer,
172 		 size_t, sigsetsize)
173 {
174 	struct k_sigaction new_ka, old_ka;
175 	int ret;
176 
177 	/* XXX: Don't preclude handling different sized sigset_t's.  */
178 	if (sigsetsize != sizeof(sigset_t))
179 		return -EINVAL;
180 
181 	if (act) {
182 		new_ka.ka_restorer = restorer;
183 		if (copy_from_user(&new_ka.sa, act, sizeof(*act)))
184 			return -EFAULT;
185 	}
186 
187 	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
188 
189 	if (!ret && oact) {
190 		if (copy_to_user(oact, &old_ka.sa, sizeof(*oact)))
191 			return -EFAULT;
192 	}
193 
194 	return ret;
195 }
196 
197 SYSCALL_DEFINE2(getdomainname, char __user *, name, int, len)
198 {
199 	int nlen, err;
200 	char tmp[__NEW_UTS_LEN + 1];
201 
202 	if (len < 0)
203 		return -EINVAL;
204 
205 	down_read(&uts_sem);
206 
207 	nlen = strlen(utsname()->domainname) + 1;
208 	err = -EINVAL;
209 	if (nlen > len)
210 		goto out_unlock;
211 	memcpy(tmp, utsname()->domainname, nlen);
212 
213 	up_read(&uts_sem);
214 
215 	if (copy_to_user(name, tmp, nlen))
216 		return -EFAULT;
217 	return 0;
218 
219 out_unlock:
220 	up_read(&uts_sem);
221 	return err;
222 }
223