fs/sysv/file.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/fs/sysv/file.c
   4  *
   5  *  minix/file.c
   6  *  Copyright (C) 1991, 1992  Linus Torvalds
   7  *
   8  *  coh/file.c
   9  *  Copyright (C) 1993  Pascal Haible, Bruno Haible
  10  *
  11  *  sysv/file.c
  12  *  Copyright (C) 1993  Bruno Haible
  13  *
  14  *  SystemV/Coherent regular file handling primitives
  15  */
  16
  17 #include "sysv.h"
  18
  19 /*
  20  * We have mostly NULLs here: the current defaults are OK for
  21  * the coh filesystem.
  22  */
  23 const struct file_operations sysv_file_operations = {
  24         .llseek         = generic_file_llseek,
  25         .read_iter      = generic_file_read_iter,
  26         .write_iter     = generic_file_write_iter,
  27         .mmap           = generic_file_mmap,
  28         .fsync          = generic_file_fsync,
  29         .splice_read    = filemap_splice_read,
  30 };
  31
  32 static int sysv_setattr(struct mnt_idmap *idmap,
  33                         struct dentry *dentry, struct iattr *attr)
  34 {
  35         struct inode *inode = d_inode(dentry);
  36         int error;
  37
  38         error = setattr_prepare(&nop_mnt_idmap, dentry, attr);
  39         if (error)
  40                 return error;
  41
  42         if ((attr->ia_valid & ATTR_SIZE) &&
  43             attr->ia_size != i_size_read(inode)) {
  44                 error = inode_newsize_ok(inode, attr->ia_size);
  45                 if (error)
  46                         return error;
  47                 truncate_setsize(inode, attr->ia_size);
  48                 sysv_truncate(inode);
  49         }
  50
  51         setattr_copy(&nop_mnt_idmap, inode, attr);
  52         mark_inode_dirty(inode);
  53         return 0;
  54 }
  55
  56 const struct inode_operations sysv_file_inode_operations = {
  57         .setattr        = sysv_setattr,
  58         .getattr        = sysv_getattr,
  59 };