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  */
SYSCALL_DEFINE0(getpagesize)37 SYSCALL_DEFINE0(getpagesize)
38 {
39 	return PAGE_SIZE; /* Possibly older binaries want 8192 on sun4's? */
40 }
41 
arch_get_unmapped_area(struct file * filp,unsigned long addr,unsigned long len,unsigned long pgoff,unsigned long flags)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  */
SYSCALL_DEFINE0(sparc_pipe)76 SYSCALL_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];
86 out:
87 	return error;
88 }
89 
sparc_mmap_check(unsigned long addr,unsigned long len)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 
SYSCALL_DEFINE6(mmap2,unsigned long,addr,unsigned long,len,unsigned long,prot,unsigned long,flags,unsigned long,fd,unsigned long,pgoff)101 SYSCALL_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 
SYSCALL_DEFINE6(mmap,unsigned long,addr,unsigned long,len,unsigned long,prot,unsigned long,flags,unsigned long,fd,unsigned long,off)111 SYSCALL_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 
SYSCALL_DEFINE5(sparc_remap_file_pages,unsigned long,start,unsigned long,size,unsigned long,prot,unsigned long,pgoff,unsigned long,flags)119 SYSCALL_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 
SYSCALL_DEFINE0(nis_syscall)130 SYSCALL_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 
147 asmlinkage void
sparc_breakpoint(struct pt_regs * regs)148 sparc_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 
SYSCALL_DEFINE3(sparc_sigaction,int,sig,struct old_sigaction __user *,act,struct old_sigaction __user *,oact)161 SYSCALL_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 
SYSCALL_DEFINE5(rt_sigaction,int,sig,const struct sigaction __user *,act,struct sigaction __user *,oact,void __user *,restorer,size_t,sigsetsize)169 SYSCALL_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 
SYSCALL_DEFINE2(getdomainname,char __user *,name,int,len)198 SYSCALL_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 
220 out_unlock:
221 	up_read(&uts_sem);
222 	return err;
223 }
224