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 <linux/linkage.h> 21 #include <linux/stringify.h> 22 #include <linux/errno.h> 23 #include <linux/syscalls.h> 24 #include <linux/file.h> 25 #include <linux/fs.h> 26 #include <linux/mman.h> 27 #include <linux/sched/mm.h> 28 #include <linux/shm.h> 29 30 syscall_t sys_call_table[] /* FIXME __cacheline_aligned */= { 31 #define __SYSCALL(nr, entry) (syscall_t)entry, 32 #include <asm/syscall_table.h> 33 }; 34 35 #define COLOUR_ALIGN(addr, pgoff) \ 36 ((((addr) + SHMLBA - 1) & ~(SHMLBA - 1)) + \ 37 (((pgoff) << PAGE_SHIFT) & (SHMLBA - 1))) 38 39 asmlinkage long xtensa_shmat(int shmid, char __user *shmaddr, int shmflg) 40 { 41 unsigned long ret; 42 long err; 43 44 err = do_shmat(shmid, shmaddr, shmflg, &ret, SHMLBA); 45 if (err) 46 return err; 47 return (long)ret; 48 } 49 50 asmlinkage long xtensa_fadvise64_64(int fd, int advice, 51 unsigned long long offset, unsigned long long len) 52 { 53 return ksys_fadvise64_64(fd, offset, len, advice); 54 } 55 56 #ifdef CONFIG_MMU 57 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, 58 unsigned long len, unsigned long pgoff, unsigned long flags) 59 { 60 struct vm_area_struct *vmm; 61 62 if (flags & MAP_FIXED) { 63 /* We do not accept a shared mapping if it would violate 64 * cache aliasing constraints. 65 */ 66 if ((flags & MAP_SHARED) && 67 ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1))) 68 return -EINVAL; 69 return addr; 70 } 71 72 if (len > TASK_SIZE) 73 return -ENOMEM; 74 if (!addr) 75 addr = TASK_UNMAPPED_BASE; 76 77 if (flags & MAP_SHARED) 78 addr = COLOUR_ALIGN(addr, pgoff); 79 else 80 addr = PAGE_ALIGN(addr); 81 82 for (vmm = find_vma(current->mm, addr); ; vmm = vmm->vm_next) { 83 /* At this point: (!vmm || addr < vmm->vm_end). */ 84 if (TASK_SIZE - len < addr) 85 return -ENOMEM; 86 if (!vmm || addr + len <= vm_start_gap(vmm)) 87 return addr; 88 addr = vmm->vm_end; 89 if (flags & MAP_SHARED) 90 addr = COLOUR_ALIGN(addr, pgoff); 91 } 92 } 93 #endif 94