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 #include <linux/compat.h> 22 #include <linux/personality.h> 23 #include <linux/sched.h> 24 #include <linux/slab.h> 25 #include <linux/syscalls.h> 26 #include <linux/uaccess.h> 27 28 #include <asm/cacheflush.h> 29 #include <asm/unistd32.h> 30 31 asmlinkage int compat_sys_fork(struct pt_regs *regs) 32 { 33 return do_fork(SIGCHLD, regs->compat_sp, regs, 0, NULL, NULL); 34 } 35 36 asmlinkage int compat_sys_clone(unsigned long clone_flags, unsigned long newsp, 37 int __user *parent_tidptr, int tls_val, 38 int __user *child_tidptr, struct pt_regs *regs) 39 { 40 if (!newsp) 41 newsp = regs->compat_sp; 42 43 return do_fork(clone_flags, newsp, regs, 0, parent_tidptr, child_tidptr); 44 } 45 46 asmlinkage int compat_sys_vfork(struct pt_regs *regs) 47 { 48 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->compat_sp, 49 regs, 0, NULL, NULL); 50 } 51 52 asmlinkage int compat_sys_execve(const char __user *filenamei, 53 compat_uptr_t argv, compat_uptr_t envp, 54 struct pt_regs *regs) 55 { 56 int error; 57 struct filename *filename; 58 59 filename = getname(filenamei); 60 error = PTR_ERR(filename); 61 if (IS_ERR(filename)) 62 goto out; 63 error = compat_do_execve(filename->name, compat_ptr(argv), 64 compat_ptr(envp), regs); 65 putname(filename); 66 out: 67 return error; 68 } 69 70 asmlinkage int compat_sys_sched_rr_get_interval(compat_pid_t pid, 71 struct compat_timespec __user *interval) 72 { 73 struct timespec t; 74 int ret; 75 mm_segment_t old_fs = get_fs(); 76 77 set_fs(KERNEL_DS); 78 ret = sys_sched_rr_get_interval(pid, (struct timespec __user *)&t); 79 set_fs(old_fs); 80 if (put_compat_timespec(&t, interval)) 81 return -EFAULT; 82 return ret; 83 } 84 85 static inline void 86 do_compat_cache_op(unsigned long start, unsigned long end, int flags) 87 { 88 struct mm_struct *mm = current->active_mm; 89 struct vm_area_struct *vma; 90 91 if (end < start || flags) 92 return; 93 94 down_read(&mm->mmap_sem); 95 vma = find_vma(mm, start); 96 if (vma && vma->vm_start < end) { 97 if (start < vma->vm_start) 98 start = vma->vm_start; 99 if (end > vma->vm_end) 100 end = vma->vm_end; 101 up_read(&mm->mmap_sem); 102 __flush_cache_user_range(start & PAGE_MASK, PAGE_ALIGN(end)); 103 return; 104 } 105 up_read(&mm->mmap_sem); 106 } 107 108 /* 109 * Handle all unrecognised system calls. 110 */ 111 long compat_arm_syscall(struct pt_regs *regs) 112 { 113 unsigned int no = regs->regs[7]; 114 115 switch (no) { 116 /* 117 * Flush a region from virtual address 'r0' to virtual address 'r1' 118 * _exclusive_. There is no alignment requirement on either address; 119 * user space does not need to know the hardware cache layout. 120 * 121 * r2 contains flags. It should ALWAYS be passed as ZERO until it 122 * is defined to be something else. For now we ignore it, but may 123 * the fires of hell burn in your belly if you break this rule. ;) 124 * 125 * (at a later date, we may want to allow this call to not flush 126 * various aspects of the cache. Passing '0' will guarantee that 127 * everything necessary gets flushed to maintain consistency in 128 * the specified region). 129 */ 130 case __ARM_NR_compat_cacheflush: 131 do_compat_cache_op(regs->regs[0], regs->regs[1], regs->regs[2]); 132 return 0; 133 134 case __ARM_NR_compat_set_tls: 135 current->thread.tp_value = regs->regs[0]; 136 asm ("msr tpidrro_el0, %0" : : "r" (regs->regs[0])); 137 return 0; 138 139 default: 140 return -ENOSYS; 141 } 142 } 143