1 /* 2 * Based on arch/arm/kernel/sys_arm.c 3 * 4 * Copyright (C) People who wrote linux/arch/i386/kernel/sys_i386.c 5 * Copyright (C) 1995, 1996 Russell King. 6 * Copyright (C) 2012 ARM Ltd. 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2 as 10 * published by the Free Software Foundation. 11 * 12 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program. If not, see <http://www.gnu.org/licenses/>. 19 */ 20 21 #define __SYSCALL_COMPAT 22 23 #include <linux/compat.h> 24 #include <linux/personality.h> 25 #include <linux/sched.h> 26 #include <linux/slab.h> 27 #include <linux/syscalls.h> 28 #include <linux/uaccess.h> 29 30 #include <asm/cacheflush.h> 31 #include <asm/unistd.h> 32 33 asmlinkage int compat_sys_fork(struct pt_regs *regs) 34 { 35 return do_fork(SIGCHLD, regs->compat_sp, regs, 0, NULL, NULL); 36 } 37 38 asmlinkage int compat_sys_clone(unsigned long clone_flags, unsigned long newsp, 39 int __user *parent_tidptr, int tls_val, 40 int __user *child_tidptr, struct pt_regs *regs) 41 { 42 if (!newsp) 43 newsp = regs->compat_sp; 44 45 return do_fork(clone_flags, newsp, regs, 0, parent_tidptr, child_tidptr); 46 } 47 48 asmlinkage int compat_sys_vfork(struct pt_regs *regs) 49 { 50 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->compat_sp, 51 regs, 0, NULL, NULL); 52 } 53 54 asmlinkage int compat_sys_execve(const char __user *filenamei, 55 compat_uptr_t argv, compat_uptr_t envp, 56 struct pt_regs *regs) 57 { 58 int error; 59 char * filename; 60 61 filename = getname(filenamei); 62 error = PTR_ERR(filename); 63 if (IS_ERR(filename)) 64 goto out; 65 error = compat_do_execve(filename, compat_ptr(argv), compat_ptr(envp), 66 regs); 67 putname(filename); 68 out: 69 return error; 70 } 71 72 asmlinkage int compat_sys_sched_rr_get_interval(compat_pid_t pid, 73 struct compat_timespec __user *interval) 74 { 75 struct timespec t; 76 int ret; 77 mm_segment_t old_fs = get_fs(); 78 79 set_fs(KERNEL_DS); 80 ret = sys_sched_rr_get_interval(pid, (struct timespec __user *)&t); 81 set_fs(old_fs); 82 if (put_compat_timespec(&t, interval)) 83 return -EFAULT; 84 return ret; 85 } 86 87 asmlinkage int compat_sys_sendfile(int out_fd, int in_fd, 88 compat_off_t __user *offset, s32 count) 89 { 90 mm_segment_t old_fs = get_fs(); 91 int ret; 92 off_t of; 93 94 if (offset && get_user(of, offset)) 95 return -EFAULT; 96 97 set_fs(KERNEL_DS); 98 ret = sys_sendfile(out_fd, in_fd, offset ? (off_t __user *)&of : NULL, 99 count); 100 set_fs(old_fs); 101 102 if (offset && put_user(of, offset)) 103 return -EFAULT; 104 return ret; 105 } 106 107 static inline void 108 do_compat_cache_op(unsigned long start, unsigned long end, int flags) 109 { 110 struct mm_struct *mm = current->active_mm; 111 struct vm_area_struct *vma; 112 113 if (end < start || flags) 114 return; 115 116 down_read(&mm->mmap_sem); 117 vma = find_vma(mm, start); 118 if (vma && vma->vm_start < end) { 119 if (start < vma->vm_start) 120 start = vma->vm_start; 121 if (end > vma->vm_end) 122 end = vma->vm_end; 123 up_read(&mm->mmap_sem); 124 __flush_cache_user_range(start & PAGE_MASK, PAGE_ALIGN(end)); 125 return; 126 } 127 up_read(&mm->mmap_sem); 128 } 129 130 /* 131 * Handle all unrecognised system calls. 132 */ 133 long compat_arm_syscall(struct pt_regs *regs) 134 { 135 unsigned int no = regs->regs[7]; 136 137 switch (no) { 138 /* 139 * Flush a region from virtual address 'r0' to virtual address 'r1' 140 * _exclusive_. There is no alignment requirement on either address; 141 * user space does not need to know the hardware cache layout. 142 * 143 * r2 contains flags. It should ALWAYS be passed as ZERO until it 144 * is defined to be something else. For now we ignore it, but may 145 * the fires of hell burn in your belly if you break this rule. ;) 146 * 147 * (at a later date, we may want to allow this call to not flush 148 * various aspects of the cache. Passing '0' will guarantee that 149 * everything necessary gets flushed to maintain consistency in 150 * the specified region). 151 */ 152 case __ARM_NR_compat_cacheflush: 153 do_compat_cache_op(regs->regs[0], regs->regs[1], regs->regs[2]); 154 return 0; 155 156 case __ARM_NR_compat_set_tls: 157 current->thread.tp_value = regs->regs[0]; 158 asm ("msr tpidrro_el0, %0" : : "r" (regs->regs[0])); 159 return 0; 160 161 default: 162 return -ENOSYS; 163 } 164 } 165