xref: /openbmc/linux/arch/sparc/kernel/sys_sparc_32.c (revision feac8c8b)
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 asmlinkage unsigned long sys_getpagesize(void)
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.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  */
76 asmlinkage long sparc_pipe(struct pt_regs *regs)
77 {
78 	int fd[2];
79 	int error;
80 
81 	error = do_pipe_flags(fd, 0);
82 	if (error)
83 		goto out;
84 	regs->u_regs[UREG_I1] = fd[1];
85 	error = fd[0];
86 out:
87 	return error;
88 }
89 
90 int 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 
101 asmlinkage long sys_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 sys_mmap_pgoff(addr, len, prot, flags, fd,
108 			      pgoff >> (PAGE_SHIFT - 12));
109 }
110 
111 asmlinkage long sys_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 sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
117 }
118 
119 long 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 
130 /* we come to here via sys_nis_syscall so it can setup the regs argument */
131 asmlinkage unsigned long
132 c_sys_nis_syscall (struct pt_regs *regs)
133 {
134 	static int count = 0;
135 
136 	if (count++ > 5)
137 		return -ENOSYS;
138 	printk ("%s[%d]: Unimplemented SPARC system call %d\n",
139 		current->comm, task_pid_nr(current), (int)regs->u_regs[1]);
140 #ifdef DEBUG_UNIMP_SYSCALL
141 	show_regs (regs);
142 #endif
143 	return -ENOSYS;
144 }
145 
146 /* #define DEBUG_SPARC_BREAKPOINT */
147 
148 asmlinkage void
149 sparc_breakpoint (struct pt_regs *regs)
150 {
151 	siginfo_t info;
152 
153 #ifdef DEBUG_SPARC_BREAKPOINT
154         printk ("TRAP: Entering kernel PC=%x, nPC=%x\n", regs->pc, regs->npc);
155 #endif
156 	info.si_signo = SIGTRAP;
157 	info.si_errno = 0;
158 	info.si_code = TRAP_BRKPT;
159 	info.si_addr = (void __user *)regs->pc;
160 	info.si_trapno = 0;
161 	force_sig_info(SIGTRAP, &info, current);
162 
163 #ifdef DEBUG_SPARC_BREAKPOINT
164 	printk ("TRAP: Returning to space: PC=%x nPC=%x\n", regs->pc, regs->npc);
165 #endif
166 }
167 
168 SYSCALL_DEFINE3(sparc_sigaction, int, sig,
169 		struct old_sigaction __user *,act,
170 		struct old_sigaction __user *,oact)
171 {
172 	WARN_ON_ONCE(sig >= 0);
173 	return sys_sigaction(-sig, act, oact);
174 }
175 
176 SYSCALL_DEFINE5(rt_sigaction, int, sig,
177 		 const struct sigaction __user *, act,
178 		 struct sigaction __user *, oact,
179 		 void __user *, restorer,
180 		 size_t, sigsetsize)
181 {
182 	struct k_sigaction new_ka, old_ka;
183 	int ret;
184 
185 	/* XXX: Don't preclude handling different sized sigset_t's.  */
186 	if (sigsetsize != sizeof(sigset_t))
187 		return -EINVAL;
188 
189 	if (act) {
190 		new_ka.ka_restorer = restorer;
191 		if (copy_from_user(&new_ka.sa, act, sizeof(*act)))
192 			return -EFAULT;
193 	}
194 
195 	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
196 
197 	if (!ret && oact) {
198 		if (copy_to_user(oact, &old_ka.sa, sizeof(*oact)))
199 			return -EFAULT;
200 	}
201 
202 	return ret;
203 }
204 
205 asmlinkage long sys_getdomainname(char __user *name, int len)
206 {
207  	int nlen, err;
208 
209 	if (len < 0)
210 		return -EINVAL;
211 
212  	down_read(&uts_sem);
213 
214 	nlen = strlen(utsname()->domainname) + 1;
215 	err = -EINVAL;
216 	if (nlen > len)
217 		goto out;
218 
219 	err = -EFAULT;
220 	if (!copy_to_user(name, utsname()->domainname, nlen))
221 		err = 0;
222 
223 out:
224 	up_read(&uts_sem);
225 	return err;
226 }
227