xref: /openbmc/linux/arch/ia64/kernel/sys_ia64.c (revision a36954f5)
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/errno.h>
9 #include <linux/fs.h>
10 #include <linux/mm.h>
11 #include <linux/mman.h>
12 #include <linux/sched.h>
13 #include <linux/sched/mm.h>
14 #include <linux/sched/task_stack.h>
15 #include <linux/shm.h>
16 #include <linux/file.h>		/* doh, must come after sched.h... */
17 #include <linux/smp.h>
18 #include <linux/syscalls.h>
19 #include <linux/highuid.h>
20 #include <linux/hugetlb.h>
21 
22 #include <asm/shmparam.h>
23 #include <linux/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 align_mask = 0;
31 	struct mm_struct *mm = current->mm;
32 	struct vm_unmapped_area_info info;
33 
34 	if (len > RGN_MAP_LIMIT)
35 		return -ENOMEM;
36 
37 	/* handle fixed mapping: prevent overlap with huge pages */
38 	if (flags & MAP_FIXED) {
39 		if (is_hugepage_only_range(mm, addr, len))
40 			return -EINVAL;
41 		return addr;
42 	}
43 
44 #ifdef CONFIG_HUGETLB_PAGE
45 	if (REGION_NUMBER(addr) == RGN_HPAGE)
46 		addr = 0;
47 #endif
48 	if (!addr)
49 		addr = TASK_UNMAPPED_BASE;
50 
51 	if (map_shared && (TASK_SIZE > 0xfffffffful))
52 		/*
53 		 * For 64-bit tasks, align shared segments to 1MB to avoid potential
54 		 * performance penalty due to virtual aliasing (see ASDM).  For 32-bit
55 		 * tasks, we prefer to avoid exhausting the address space too quickly by
56 		 * limiting alignment to a single page.
57 		 */
58 		align_mask = PAGE_MASK & (SHMLBA - 1);
59 
60 	info.flags = 0;
61 	info.length = len;
62 	info.low_limit = addr;
63 	info.high_limit = TASK_SIZE;
64 	info.align_mask = align_mask;
65 	info.align_offset = 0;
66 	return vm_unmapped_area(&info);
67 }
68 
69 asmlinkage long
70 ia64_getpriority (int which, int who)
71 {
72 	long prio;
73 
74 	prio = sys_getpriority(which, who);
75 	if (prio >= 0) {
76 		force_successful_syscall_return();
77 		prio = 20 - prio;
78 	}
79 	return prio;
80 }
81 
82 /* XXX obsolete, but leave it here until the old libc is gone... */
83 asmlinkage unsigned long
84 sys_getpagesize (void)
85 {
86 	return PAGE_SIZE;
87 }
88 
89 asmlinkage unsigned long
90 ia64_brk (unsigned long brk)
91 {
92 	unsigned long retval = sys_brk(brk);
93 	force_successful_syscall_return();
94 	return retval;
95 }
96 
97 /*
98  * On IA-64, we return the two file descriptors in ret0 and ret1 (r8
99  * and r9) as this is faster than doing a copy_to_user().
100  */
101 asmlinkage long
102 sys_ia64_pipe (void)
103 {
104 	struct pt_regs *regs = task_pt_regs(current);
105 	int fd[2];
106 	int retval;
107 
108 	retval = do_pipe_flags(fd, 0);
109 	if (retval)
110 		goto out;
111 	retval = fd[0];
112 	regs->r9 = fd[1];
113   out:
114 	return retval;
115 }
116 
117 int ia64_mmap_check(unsigned long addr, unsigned long len,
118 		unsigned long flags)
119 {
120 	unsigned long roff;
121 
122 	/*
123 	 * Don't permit mappings into unmapped space, the virtual page table
124 	 * of a region, or across a region boundary.  Note: RGN_MAP_LIMIT is
125 	 * equal to 2^n-PAGE_SIZE (for some integer n <= 61) and len > 0.
126 	 */
127 	roff = REGION_OFFSET(addr);
128 	if ((len > RGN_MAP_LIMIT) || (roff > (RGN_MAP_LIMIT - len)))
129 		return -EINVAL;
130 	return 0;
131 }
132 
133 /*
134  * mmap2() is like mmap() except that the offset is expressed in units
135  * of PAGE_SIZE (instead of bytes).  This allows to mmap2() (pieces
136  * of) files that are larger than the address space of the CPU.
137  */
138 asmlinkage unsigned long
139 sys_mmap2 (unsigned long addr, unsigned long len, int prot, int flags, int fd, long pgoff)
140 {
141 	addr = sys_mmap_pgoff(addr, len, prot, flags, fd, pgoff);
142 	if (!IS_ERR((void *) addr))
143 		force_successful_syscall_return();
144 	return addr;
145 }
146 
147 asmlinkage unsigned long
148 sys_mmap (unsigned long addr, unsigned long len, int prot, int flags, int fd, long off)
149 {
150 	if (offset_in_page(off) != 0)
151 		return -EINVAL;
152 
153 	addr = sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
154 	if (!IS_ERR((void *) addr))
155 		force_successful_syscall_return();
156 	return addr;
157 }
158 
159 asmlinkage unsigned long
160 ia64_mremap (unsigned long addr, unsigned long old_len, unsigned long new_len, unsigned long flags,
161 	     unsigned long new_addr)
162 {
163 	addr = sys_mremap(addr, old_len, new_len, flags, new_addr);
164 	if (!IS_ERR((void *) addr))
165 		force_successful_syscall_return();
166 	return addr;
167 }
168 
169 #ifndef CONFIG_PCI
170 
171 asmlinkage long
172 sys_pciconfig_read (unsigned long bus, unsigned long dfn, unsigned long off, unsigned long len,
173 		    void *buf)
174 {
175 	return -ENOSYS;
176 }
177 
178 asmlinkage long
179 sys_pciconfig_write (unsigned long bus, unsigned long dfn, unsigned long off, unsigned long len,
180 		     void *buf)
181 {
182 	return -ENOSYS;
183 }
184 
185 #endif /* CONFIG_PCI */
186