sanitize rt_sigaction() situation a bit
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / sparc / kernel / sys_sparc_32.c
1 /* linux/arch/sparc/kernel/sys_sparc.c
2 *
3 * This file contains various random system calls that
4 * have a non-standard calling sequence on the Linux/sparc
5 * platform.
6 */
7
8 #include <linux/errno.h>
9 #include <linux/types.h>
10 #include <linux/sched.h>
11 #include <linux/mm.h>
12 #include <linux/fs.h>
13 #include <linux/file.h>
14 #include <linux/sem.h>
15 #include <linux/msg.h>
16 #include <linux/shm.h>
17 #include <linux/stat.h>
18 #include <linux/syscalls.h>
19 #include <linux/mman.h>
20 #include <linux/utsname.h>
21 #include <linux/smp.h>
22 #include <linux/ipc.h>
23
24 #include <asm/uaccess.h>
25 #include <asm/unistd.h>
26
27 /* #define DEBUG_UNIMP_SYSCALL */
28
29 /* XXX Make this per-binary type, this way we can detect the type of
30 * XXX a binary. Every Sparc executable calls this very early on.
31 */
32 asmlinkage unsigned long sys_getpagesize(void)
33 {
34 return PAGE_SIZE; /* Possibly older binaries want 8192 on sun4's? */
35 }
36
37 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags)
38 {
39 struct vm_unmapped_area_info info;
40
41 if (flags & MAP_FIXED) {
42 /* We do not accept a shared mapping if it would violate
43 * cache aliasing constraints.
44 */
45 if ((flags & MAP_SHARED) &&
46 ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
47 return -EINVAL;
48 return addr;
49 }
50
51 /* See asm-sparc/uaccess.h */
52 if (len > TASK_SIZE - PAGE_SIZE)
53 return -ENOMEM;
54 if (!addr)
55 addr = TASK_UNMAPPED_BASE;
56
57 info.flags = 0;
58 info.length = len;
59 info.low_limit = addr;
60 info.high_limit = TASK_SIZE;
61 info.align_mask = (flags & MAP_SHARED) ?
62 (PAGE_MASK & (SHMLBA - 1)) : 0;
63 info.align_offset = pgoff << PAGE_SHIFT;
64 return vm_unmapped_area(&info);
65 }
66
67 /*
68 * sys_pipe() is the normal C calling standard for creating
69 * a pipe. It's not the way unix traditionally does this, though.
70 */
71 asmlinkage int sparc_pipe(struct pt_regs *regs)
72 {
73 int fd[2];
74 int error;
75
76 error = do_pipe_flags(fd, 0);
77 if (error)
78 goto out;
79 regs->u_regs[UREG_I1] = fd[1];
80 error = fd[0];
81 out:
82 return error;
83 }
84
85 int sparc_mmap_check(unsigned long addr, unsigned long len)
86 {
87 /* See asm-sparc/uaccess.h */
88 if (len > TASK_SIZE - PAGE_SIZE || addr + len > TASK_SIZE - PAGE_SIZE)
89 return -EINVAL;
90
91 return 0;
92 }
93
94 /* Linux version of mmap */
95
96 asmlinkage unsigned long sys_mmap2(unsigned long addr, unsigned long len,
97 unsigned long prot, unsigned long flags, unsigned long fd,
98 unsigned long pgoff)
99 {
100 /* Make sure the shift for mmap2 is constant (12), no matter what PAGE_SIZE
101 we have. */
102 return sys_mmap_pgoff(addr, len, prot, flags, fd,
103 pgoff >> (PAGE_SHIFT - 12));
104 }
105
106 asmlinkage unsigned long sys_mmap(unsigned long addr, unsigned long len,
107 unsigned long prot, unsigned long flags, unsigned long fd,
108 unsigned long off)
109 {
110 /* no alignment check? */
111 return sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
112 }
113
114 long sparc_remap_file_pages(unsigned long start, unsigned long size,
115 unsigned long prot, unsigned long pgoff,
116 unsigned long flags)
117 {
118 /* This works on an existing mmap so we don't need to validate
119 * the range as that was done at the original mmap call.
120 */
121 return sys_remap_file_pages(start, size, prot,
122 (pgoff >> (PAGE_SHIFT - 12)), flags);
123 }
124
125 /* we come to here via sys_nis_syscall so it can setup the regs argument */
126 asmlinkage unsigned long
127 c_sys_nis_syscall (struct pt_regs *regs)
128 {
129 static int count = 0;
130
131 if (count++ > 5)
132 return -ENOSYS;
133 printk ("%s[%d]: Unimplemented SPARC system call %d\n",
134 current->comm, task_pid_nr(current), (int)regs->u_regs[1]);
135 #ifdef DEBUG_UNIMP_SYSCALL
136 show_regs (regs);
137 #endif
138 return -ENOSYS;
139 }
140
141 /* #define DEBUG_SPARC_BREAKPOINT */
142
143 asmlinkage void
144 sparc_breakpoint (struct pt_regs *regs)
145 {
146 siginfo_t info;
147
148 #ifdef DEBUG_SPARC_BREAKPOINT
149 printk ("TRAP: Entering kernel PC=%x, nPC=%x\n", regs->pc, regs->npc);
150 #endif
151 info.si_signo = SIGTRAP;
152 info.si_errno = 0;
153 info.si_code = TRAP_BRKPT;
154 info.si_addr = (void __user *)regs->pc;
155 info.si_trapno = 0;
156 force_sig_info(SIGTRAP, &info, current);
157
158 #ifdef DEBUG_SPARC_BREAKPOINT
159 printk ("TRAP: Returning to space: PC=%x nPC=%x\n", regs->pc, regs->npc);
160 #endif
161 }
162
163 asmlinkage int
164 sparc_sigaction (int sig, const struct old_sigaction __user *act,
165 struct old_sigaction __user *oact)
166 {
167 struct k_sigaction new_ka, old_ka;
168 int ret;
169
170 WARN_ON_ONCE(sig >= 0);
171 sig = -sig;
172
173 if (act) {
174 unsigned long mask;
175
176 if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
177 __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
178 __get_user(new_ka.sa.sa_restorer, &act->sa_restorer) ||
179 __get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
180 __get_user(mask, &act->sa_mask))
181 return -EFAULT;
182 siginitset(&new_ka.sa.sa_mask, mask);
183 new_ka.ka_restorer = NULL;
184 }
185
186 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
187
188 if (!ret && oact) {
189 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
190 __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
191 __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer) ||
192 __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
193 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))
194 return -EFAULT;
195 }
196
197 return ret;
198 }
199
200 SYSCALL_DEFINE5(rt_sigaction, int, sig,
201 const struct sigaction __user *, act,
202 struct sigaction __user *, oact,
203 void __user *, restorer,
204 size_t, sigsetsize)
205 {
206 struct k_sigaction new_ka, old_ka;
207 int ret;
208
209 /* XXX: Don't preclude handling different sized sigset_t's. */
210 if (sigsetsize != sizeof(sigset_t))
211 return -EINVAL;
212
213 if (act) {
214 new_ka.ka_restorer = restorer;
215 if (copy_from_user(&new_ka.sa, act, sizeof(*act)))
216 return -EFAULT;
217 }
218
219 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
220
221 if (!ret && oact) {
222 if (copy_to_user(oact, &old_ka.sa, sizeof(*oact)))
223 return -EFAULT;
224 }
225
226 return ret;
227 }
228
229 asmlinkage int sys_getdomainname(char __user *name, int len)
230 {
231 int nlen, err;
232
233 if (len < 0)
234 return -EINVAL;
235
236 down_read(&uts_sem);
237
238 nlen = strlen(utsname()->domainname) + 1;
239 err = -EINVAL;
240 if (nlen > len)
241 goto out;
242
243 err = -EFAULT;
244 if (!copy_to_user(name, utsname()->domainname, nlen))
245 err = 0;
246
247 out:
248 up_read(&uts_sem);
249 return err;
250 }