fs/ext2/file.c

   1 /*
   2  *  linux/fs/ext2/file.c
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  from
  10  *
  11  *  linux/fs/minix/file.c
  12  *
  13  *  Copyright (C) 1991, 1992  Linus Torvalds
  14  *
  15  *  ext2 fs regular file handling primitives
  16  *
  17  *  64-bit file support on 64-bit platforms by Jakub Jelinek
  18  *      (jj@sunsite.ms.mff.cuni.cz)
  19  */
  20
  21 #include <linux/time.h>
  22 #include <linux/pagemap.h>
  23 #include <linux/dax.h>
  24 #include <linux/quotaops.h>
  25 #include "ext2.h"
  26 #include "xattr.h"
  27 #include "acl.h"
  28
  29 #ifdef CONFIG_FS_DAX
  30 static int ext2_dax_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
  31 {
  32         return dax_fault(vma, vmf, ext2_get_block, NULL);
  33 }
  34
  35 static int ext2_dax_pmd_fault(struct vm_area_struct *vma, unsigned long addr,
  36                                                 pmd_t *pmd, unsigned int flags)
  37 {
  38         return dax_pmd_fault(vma, addr, pmd, flags, ext2_get_block, NULL);
  39 }
  40
  41 static int ext2_dax_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
  42 {
  43         return dax_mkwrite(vma, vmf, ext2_get_block, NULL);
  44 }
  45
  46 static const struct vm_operations_struct ext2_dax_vm_ops = {
  47         .fault          = ext2_dax_fault,
  48         .pmd_fault      = ext2_dax_pmd_fault,
  49         .page_mkwrite   = ext2_dax_mkwrite,
  50         .pfn_mkwrite    = dax_pfn_mkwrite,
  51 };
  52
  53 static int ext2_file_mmap(struct file *file, struct vm_area_struct *vma)
  54 {
  55         if (!IS_DAX(file_inode(file)))
  56                 return generic_file_mmap(file, vma);
  57
  58         file_accessed(file);
  59         vma->vm_ops = &ext2_dax_vm_ops;
  60         vma->vm_flags |= VM_MIXEDMAP | VM_HUGEPAGE;
  61         return 0;
  62 }
  63 #else
  64 #define ext2_file_mmap  generic_file_mmap
  65 #endif
  66
  67 /*
  68  * Called when filp is released. This happens when all file descriptors
  69  * for a single struct file are closed. Note that different open() calls
  70  * for the same file yield different struct file structures.
  71  */
  72 static int ext2_release_file (struct inode * inode, struct file * filp)
  73 {
  74         if (filp->f_mode & FMODE_WRITE) {
  75                 mutex_lock(&EXT2_I(inode)->truncate_mutex);
  76                 ext2_discard_reservation(inode);
  77                 mutex_unlock(&EXT2_I(inode)->truncate_mutex);
  78         }
  79         return 0;
  80 }
  81
  82 int ext2_fsync(struct file *file, loff_t start, loff_t end, int datasync)
  83 {
  84         int ret;
  85         struct super_block *sb = file->f_mapping->host->i_sb;
  86         struct address_space *mapping = sb->s_bdev->bd_inode->i_mapping;
  87
  88         ret = generic_file_fsync(file, start, end, datasync);
  89         if (ret == -EIO || test_and_clear_bit(AS_EIO, &mapping->flags)) {
  90                 /* We don't really know where the IO error happened... */
  91                 ext2_error(sb, __func__,
  92                            "detected IO error when writing metadata buffers");
  93                 ret = -EIO;
  94         }
  95         return ret;
  96 }
  97
  98 /*
  99  * We have mostly NULL's here: the current defaults are ok for
 100  * the ext2 filesystem.
 101  */
 102 const struct file_operations ext2_file_operations = {
 103         .llseek         = generic_file_llseek,
 104         .read_iter      = generic_file_read_iter,
 105         .write_iter     = generic_file_write_iter,
 106         .unlocked_ioctl = ext2_ioctl,
 107 #ifdef CONFIG_COMPAT
 108         .compat_ioctl   = ext2_compat_ioctl,
 109 #endif
 110         .mmap           = ext2_file_mmap,
 111         .open           = dquot_file_open,
 112         .release        = ext2_release_file,
 113         .fsync          = ext2_fsync,
 114         .splice_read    = generic_file_splice_read,
 115         .splice_write   = iter_file_splice_write,
 116 };
 117
 118 const struct inode_operations ext2_file_inode_operations = {
 119 #ifdef CONFIG_EXT2_FS_XATTR
 120         .setxattr       = generic_setxattr,
 121         .getxattr       = generic_getxattr,
 122         .listxattr      = ext2_listxattr,
 123         .removexattr    = generic_removexattr,
 124 #endif
 125         .setattr        = ext2_setattr,
 126         .get_acl        = ext2_get_acl,
 127         .set_acl        = ext2_set_acl,
 128         .fiemap         = ext2_fiemap,
 129 };