xref: /openbmc/linux/arch/ia64/kernel/sys_ia64.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
1 /*
2  * This file contains various system calls that have different calling
3  * conventions on different platforms.
4  *
5  * Copyright (C) 1999-2000, 2002-2003, 2005 Hewlett-Packard Co
6  *	David Mosberger-Tang <davidm@hpl.hp.com>
7  */
8 #include <linux/config.h>
9 #include <linux/errno.h>
10 #include <linux/fs.h>
11 #include <linux/mm.h>
12 #include <linux/mman.h>
13 #include <linux/sched.h>
14 #include <linux/shm.h>
15 #include <linux/file.h>		/* doh, must come after sched.h... */
16 #include <linux/smp.h>
17 #include <linux/smp_lock.h>
18 #include <linux/syscalls.h>
19 #include <linux/highuid.h>
20 #include <linux/hugetlb.h>
21 
22 #include <asm/shmparam.h>
23 #include <asm/uaccess.h>
24 
25 unsigned long
26 arch_get_unmapped_area (struct file *filp, unsigned long addr, unsigned long len,
27 			unsigned long pgoff, unsigned long flags)
28 {
29 	long map_shared = (flags & MAP_SHARED);
30 	unsigned long start_addr, align_mask = PAGE_SIZE - 1;
31 	struct mm_struct *mm = current->mm;
32 	struct vm_area_struct *vma;
33 
34 	if (len > RGN_MAP_LIMIT)
35 		return -ENOMEM;
36 
37 #ifdef CONFIG_HUGETLB_PAGE
38 	if (REGION_NUMBER(addr) == REGION_HPAGE)
39 		addr = 0;
40 #endif
41 	if (!addr)
42 		addr = mm->free_area_cache;
43 
44 	if (map_shared && (TASK_SIZE > 0xfffffffful))
45 		/*
46 		 * For 64-bit tasks, align shared segments to 1MB to avoid potential
47 		 * performance penalty due to virtual aliasing (see ASDM).  For 32-bit
48 		 * tasks, we prefer to avoid exhausting the address space too quickly by
49 		 * limiting alignment to a single page.
50 		 */
51 		align_mask = SHMLBA - 1;
52 
53   full_search:
54 	start_addr = addr = (addr + align_mask) & ~align_mask;
55 
56 	for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
57 		/* At this point:  (!vma || addr < vma->vm_end). */
58 		if (TASK_SIZE - len < addr || RGN_MAP_LIMIT - len < REGION_OFFSET(addr)) {
59 			if (start_addr != TASK_UNMAPPED_BASE) {
60 				/* Start a new search --- just in case we missed some holes.  */
61 				addr = TASK_UNMAPPED_BASE;
62 				goto full_search;
63 			}
64 			return -ENOMEM;
65 		}
66 		if (!vma || addr + len <= vma->vm_start) {
67 			/* Remember the address where we stopped this search:  */
68 			mm->free_area_cache = addr + len;
69 			return addr;
70 		}
71 		addr = (vma->vm_end + align_mask) & ~align_mask;
72 	}
73 }
74 
75 asmlinkage long
76 ia64_getpriority (int which, int who)
77 {
78 	long prio;
79 
80 	prio = sys_getpriority(which, who);
81 	if (prio >= 0) {
82 		force_successful_syscall_return();
83 		prio = 20 - prio;
84 	}
85 	return prio;
86 }
87 
88 /* XXX obsolete, but leave it here until the old libc is gone... */
89 asmlinkage unsigned long
90 sys_getpagesize (void)
91 {
92 	return PAGE_SIZE;
93 }
94 
95 asmlinkage unsigned long
96 ia64_shmat (int shmid, void __user *shmaddr, int shmflg)
97 {
98 	unsigned long raddr;
99 	int retval;
100 
101 	retval = do_shmat(shmid, shmaddr, shmflg, &raddr);
102 	if (retval < 0)
103 		return retval;
104 
105 	force_successful_syscall_return();
106 	return raddr;
107 }
108 
109 asmlinkage unsigned long
110 ia64_brk (unsigned long brk)
111 {
112 	unsigned long rlim, retval, newbrk, oldbrk;
113 	struct mm_struct *mm = current->mm;
114 
115 	/*
116 	 * Most of this replicates the code in sys_brk() except for an additional safety
117 	 * check and the clearing of r8.  However, we can't call sys_brk() because we need
118 	 * to acquire the mmap_sem before we can do the test...
119 	 */
120 	down_write(&mm->mmap_sem);
121 
122 	if (brk < mm->end_code)
123 		goto out;
124 	newbrk = PAGE_ALIGN(brk);
125 	oldbrk = PAGE_ALIGN(mm->brk);
126 	if (oldbrk == newbrk)
127 		goto set_brk;
128 
129 	/* Always allow shrinking brk. */
130 	if (brk <= mm->brk) {
131 		if (!do_munmap(mm, newbrk, oldbrk-newbrk))
132 			goto set_brk;
133 		goto out;
134 	}
135 
136 	/* Check against unimplemented/unmapped addresses: */
137 	if ((newbrk - oldbrk) > RGN_MAP_LIMIT || REGION_OFFSET(newbrk) > RGN_MAP_LIMIT)
138 		goto out;
139 
140 	/* Check against rlimit.. */
141 	rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;
142 	if (rlim < RLIM_INFINITY && brk - mm->start_data > rlim)
143 		goto out;
144 
145 	/* Check against existing mmap mappings. */
146 	if (find_vma_intersection(mm, oldbrk, newbrk+PAGE_SIZE))
147 		goto out;
148 
149 	/* Ok, looks good - let it rip. */
150 	if (do_brk(oldbrk, newbrk-oldbrk) != oldbrk)
151 		goto out;
152 set_brk:
153 	mm->brk = brk;
154 out:
155 	retval = mm->brk;
156 	up_write(&mm->mmap_sem);
157 	force_successful_syscall_return();
158 	return retval;
159 }
160 
161 /*
162  * On IA-64, we return the two file descriptors in ret0 and ret1 (r8
163  * and r9) as this is faster than doing a copy_to_user().
164  */
165 asmlinkage long
166 sys_pipe (void)
167 {
168 	struct pt_regs *regs = ia64_task_regs(current);
169 	int fd[2];
170 	int retval;
171 
172 	retval = do_pipe(fd);
173 	if (retval)
174 		goto out;
175 	retval = fd[0];
176 	regs->r9 = fd[1];
177   out:
178 	return retval;
179 }
180 
181 static inline unsigned long
182 do_mmap2 (unsigned long addr, unsigned long len, int prot, int flags, int fd, unsigned long pgoff)
183 {
184 	unsigned long roff;
185 	struct file *file = NULL;
186 
187 	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
188 	if (!(flags & MAP_ANONYMOUS)) {
189 		file = fget(fd);
190 		if (!file)
191 			return -EBADF;
192 
193 		if (!file->f_op || !file->f_op->mmap) {
194 			addr = -ENODEV;
195 			goto out;
196 		}
197 	}
198 
199 	/*
200 	 * A zero mmap always succeeds in Linux, independent of whether or not the
201 	 * remaining arguments are valid.
202 	 */
203 	if (len == 0)
204 		goto out;
205 
206 	/* Careful about overflows.. */
207 	len = PAGE_ALIGN(len);
208 	if (!len || len > TASK_SIZE) {
209 		addr = -EINVAL;
210 		goto out;
211 	}
212 
213 	/*
214 	 * Don't permit mappings into unmapped space, the virtual page table of a region,
215 	 * or across a region boundary.  Note: RGN_MAP_LIMIT is equal to 2^n-PAGE_SIZE
216 	 * (for some integer n <= 61) and len > 0.
217 	 */
218 	roff = REGION_OFFSET(addr);
219 	if ((len > RGN_MAP_LIMIT) || (roff > (RGN_MAP_LIMIT - len))) {
220 		addr = -EINVAL;
221 		goto out;
222 	}
223 
224 	down_write(&current->mm->mmap_sem);
225 	addr = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
226 	up_write(&current->mm->mmap_sem);
227 
228 out:	if (file)
229 		fput(file);
230 	return addr;
231 }
232 
233 /*
234  * mmap2() is like mmap() except that the offset is expressed in units
235  * of PAGE_SIZE (instead of bytes).  This allows to mmap2() (pieces
236  * of) files that are larger than the address space of the CPU.
237  */
238 asmlinkage unsigned long
239 sys_mmap2 (unsigned long addr, unsigned long len, int prot, int flags, int fd, long pgoff)
240 {
241 	addr = do_mmap2(addr, len, prot, flags, fd, pgoff);
242 	if (!IS_ERR((void *) addr))
243 		force_successful_syscall_return();
244 	return addr;
245 }
246 
247 asmlinkage unsigned long
248 sys_mmap (unsigned long addr, unsigned long len, int prot, int flags, int fd, long off)
249 {
250 	if (offset_in_page(off) != 0)
251 		return -EINVAL;
252 
253 	addr = do_mmap2(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
254 	if (!IS_ERR((void *) addr))
255 		force_successful_syscall_return();
256 	return addr;
257 }
258 
259 asmlinkage unsigned long
260 ia64_mremap (unsigned long addr, unsigned long old_len, unsigned long new_len, unsigned long flags,
261 	     unsigned long new_addr)
262 {
263 	extern unsigned long do_mremap (unsigned long addr,
264 					unsigned long old_len,
265 					unsigned long new_len,
266 					unsigned long flags,
267 					unsigned long new_addr);
268 
269 	down_write(&current->mm->mmap_sem);
270 	{
271 		addr = do_mremap(addr, old_len, new_len, flags, new_addr);
272 	}
273 	up_write(&current->mm->mmap_sem);
274 
275 	if (IS_ERR((void *) addr))
276 		return addr;
277 
278 	force_successful_syscall_return();
279 	return addr;
280 }
281 
282 #ifndef CONFIG_PCI
283 
284 asmlinkage long
285 sys_pciconfig_read (unsigned long bus, unsigned long dfn, unsigned long off, unsigned long len,
286 		    void *buf)
287 {
288 	return -ENOSYS;
289 }
290 
291 asmlinkage long
292 sys_pciconfig_write (unsigned long bus, unsigned long dfn, unsigned long off, unsigned long len,
293 		     void *buf)
294 {
295 	return -ENOSYS;
296 }
297 
298 #endif /* CONFIG_PCI */
299