1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * This file contains various system calls that have different calling
4 * conventions on different platforms.
5 *
6 * Copyright (C) 1999-2000, 2002-2003, 2005 Hewlett-Packard Co
7 * David Mosberger-Tang <davidm@hpl.hp.com>
8 */
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/sched/mm.h>
15 #include <linux/sched/task_stack.h>
16 #include <linux/shm.h>
17 #include <linux/file.h> /* doh, must come after sched.h... */
18 #include <linux/smp.h>
19 #include <linux/syscalls.h>
20 #include <linux/highuid.h>
21 #include <linux/hugetlb.h>
22
23 #include <asm/shmparam.h>
24 #include <linux/uaccess.h>
25
26 unsigned long
arch_get_unmapped_area(struct file * filp,unsigned long addr,unsigned long len,unsigned long pgoff,unsigned long flags)27 arch_get_unmapped_area (struct file *filp, unsigned long addr, unsigned long len,
28 unsigned long pgoff, unsigned long flags)
29 {
30 long map_shared = (flags & MAP_SHARED);
31 unsigned long align_mask = 0;
32 struct mm_struct *mm = current->mm;
33 struct vm_unmapped_area_info info;
34
35 if (len > RGN_MAP_LIMIT)
36 return -ENOMEM;
37
38 /* handle fixed mapping: prevent overlap with huge pages */
39 if (flags & MAP_FIXED) {
40 if (is_hugepage_only_range(mm, addr, len))
41 return -EINVAL;
42 return addr;
43 }
44
45 #ifdef CONFIG_HUGETLB_PAGE
46 if (REGION_NUMBER(addr) == RGN_HPAGE)
47 addr = 0;
48 #endif
49 if (!addr)
50 addr = TASK_UNMAPPED_BASE;
51
52 if (map_shared && (TASK_SIZE > 0xfffffffful))
53 /*
54 * For 64-bit tasks, align shared segments to 1MB to avoid potential
55 * performance penalty due to virtual aliasing (see ASDM). For 32-bit
56 * tasks, we prefer to avoid exhausting the address space too quickly by
57 * limiting alignment to a single page.
58 */
59 align_mask = PAGE_MASK & (SHMLBA - 1);
60
61 info.flags = 0;
62 info.length = len;
63 info.low_limit = addr;
64 info.high_limit = TASK_SIZE;
65 info.align_mask = align_mask;
66 info.align_offset = 0;
67 return vm_unmapped_area(&info);
68 }
69
70 asmlinkage long
ia64_getpriority(int which,int who)71 ia64_getpriority (int which, int who)
72 {
73 long prio;
74
75 prio = sys_getpriority(which, who);
76 if (prio >= 0) {
77 force_successful_syscall_return();
78 prio = 20 - prio;
79 }
80 return prio;
81 }
82
83 /* XXX obsolete, but leave it here until the old libc is gone... */
84 asmlinkage unsigned long
sys_getpagesize(void)85 sys_getpagesize (void)
86 {
87 return PAGE_SIZE;
88 }
89
90 asmlinkage unsigned long
ia64_brk(unsigned long brk)91 ia64_brk (unsigned long brk)
92 {
93 unsigned long retval = sys_brk(brk);
94 force_successful_syscall_return();
95 return retval;
96 }
97
98 /*
99 * On IA-64, we return the two file descriptors in ret0 and ret1 (r8
100 * and r9) as this is faster than doing a copy_to_user().
101 */
102 asmlinkage long
sys_ia64_pipe(void)103 sys_ia64_pipe (void)
104 {
105 struct pt_regs *regs = task_pt_regs(current);
106 int fd[2];
107 int retval;
108
109 retval = do_pipe_flags(fd, 0);
110 if (retval)
111 goto out;
112 retval = fd[0];
113 regs->r9 = fd[1];
114 out:
115 return retval;
116 }
117
ia64_mmap_check(unsigned long addr,unsigned long len,unsigned long flags)118 int ia64_mmap_check(unsigned long addr, unsigned long len,
119 unsigned long flags)
120 {
121 unsigned long roff;
122
123 /*
124 * Don't permit mappings into unmapped space, the virtual page table
125 * of a region, or across a region boundary. Note: RGN_MAP_LIMIT is
126 * equal to 2^n-PAGE_SIZE (for some integer n <= 61) and len > 0.
127 */
128 roff = REGION_OFFSET(addr);
129 if ((len > RGN_MAP_LIMIT) || (roff > (RGN_MAP_LIMIT - len)))
130 return -EINVAL;
131 return 0;
132 }
133
134 /*
135 * mmap2() is like mmap() except that the offset is expressed in units
136 * of PAGE_SIZE (instead of bytes). This allows to mmap2() (pieces
137 * of) files that are larger than the address space of the CPU.
138 */
139 asmlinkage unsigned long
sys_mmap2(unsigned long addr,unsigned long len,int prot,int flags,int fd,long pgoff)140 sys_mmap2 (unsigned long addr, unsigned long len, int prot, int flags, int fd, long pgoff)
141 {
142 addr = ksys_mmap_pgoff(addr, len, prot, flags, fd, pgoff);
143 if (!IS_ERR((void *) addr))
144 force_successful_syscall_return();
145 return addr;
146 }
147
148 asmlinkage unsigned long
sys_mmap(unsigned long addr,unsigned long len,int prot,int flags,int fd,long off)149 sys_mmap (unsigned long addr, unsigned long len, int prot, int flags, int fd, long off)
150 {
151 if (offset_in_page(off) != 0)
152 return -EINVAL;
153
154 addr = ksys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
155 if (!IS_ERR((void *) addr))
156 force_successful_syscall_return();
157 return addr;
158 }
159
160 asmlinkage unsigned long
ia64_mremap(unsigned long addr,unsigned long old_len,unsigned long new_len,unsigned long flags,unsigned long new_addr)161 ia64_mremap (unsigned long addr, unsigned long old_len, unsigned long new_len, unsigned long flags,
162 unsigned long new_addr)
163 {
164 addr = sys_mremap(addr, old_len, new_len, flags, new_addr);
165 if (!IS_ERR((void *) addr))
166 force_successful_syscall_return();
167 return addr;
168 }
169
