1 /* 2 * arch/xtensa/kernel/syscall.c 3 * 4 * This file is subject to the terms and conditions of the GNU General Public 5 * License. See the file "COPYING" in the main directory of this archive 6 * for more details. 7 * 8 * Copyright (C) 2001 - 2005 Tensilica Inc. 9 * Copyright (C) 2000 Silicon Graphics, Inc. 10 * Copyright (C) 1995 - 2000 by Ralf Baechle 11 * 12 * Joe Taylor <joe@tensilica.com, joetylr@yahoo.com> 13 * Marc Gauthier <marc@tensilica.com, marc@alumni.uwaterloo.ca> 14 * Chris Zankel <chris@zankel.net> 15 * Kevin Chea 16 * 17 */ 18 #include <linux/uaccess.h> 19 #include <asm/syscall.h> 20 #include <asm/unistd.h> 21 #include <linux/linkage.h> 22 #include <linux/stringify.h> 23 #include <linux/errno.h> 24 #include <linux/syscalls.h> 25 #include <linux/file.h> 26 #include <linux/fs.h> 27 #include <linux/mman.h> 28 #include <linux/sched/mm.h> 29 #include <linux/shm.h> 30 31 typedef void (*syscall_t)(void); 32 33 syscall_t sys_call_table[__NR_syscall_count] /* FIXME __cacheline_aligned */= { 34 [0 ... __NR_syscall_count - 1] = (syscall_t)&sys_ni_syscall, 35 36 #define __SYSCALL(nr,symbol,nargs) [ nr ] = (syscall_t)symbol, 37 #include <uapi/asm/unistd.h> 38 }; 39 40 #define COLOUR_ALIGN(addr, pgoff) \ 41 ((((addr) + SHMLBA - 1) & ~(SHMLBA - 1)) + \ 42 (((pgoff) << PAGE_SHIFT) & (SHMLBA - 1))) 43 44 asmlinkage long xtensa_shmat(int shmid, char __user *shmaddr, int shmflg) 45 { 46 unsigned long ret; 47 long err; 48 49 err = do_shmat(shmid, shmaddr, shmflg, &ret, SHMLBA); 50 if (err) 51 return err; 52 return (long)ret; 53 } 54 55 asmlinkage long xtensa_fadvise64_64(int fd, int advice, 56 unsigned long long offset, unsigned long long len) 57 { 58 return sys_fadvise64_64(fd, offset, len, advice); 59 } 60 61 #ifdef CONFIG_MMU 62 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, 63 unsigned long len, unsigned long pgoff, unsigned long flags) 64 { 65 struct vm_area_struct *vmm; 66 67 if (flags & MAP_FIXED) { 68 /* We do not accept a shared mapping if it would violate 69 * cache aliasing constraints. 70 */ 71 if ((flags & MAP_SHARED) && 72 ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1))) 73 return -EINVAL; 74 return addr; 75 } 76 77 if (len > TASK_SIZE) 78 return -ENOMEM; 79 if (!addr) 80 addr = TASK_UNMAPPED_BASE; 81 82 if (flags & MAP_SHARED) 83 addr = COLOUR_ALIGN(addr, pgoff); 84 else 85 addr = PAGE_ALIGN(addr); 86 87 for (vmm = find_vma(current->mm, addr); ; vmm = vmm->vm_next) { 88 /* At this point: (!vmm || addr < vmm->vm_end). */ 89 if (TASK_SIZE - len < addr) 90 return -ENOMEM; 91 if (!vmm || addr + len <= vm_start_gap(vmm)) 92 return addr; 93 addr = vmm->vm_end; 94 if (flags & MAP_SHARED) 95 addr = COLOUR_ALIGN(addr, pgoff); 96 } 97 } 98 #endif 99