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1// SPDX-License-Identifier: GPL-2.0+2/*3 * NILFS regular file handling primitives including fsync().4 *5 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.6 *7 * Written by Amagai Yoshiji and Ryusuke Konishi.8 */9 10#include <linux/fs.h>11#include <linux/mm.h>12#include <linux/writeback.h>13#include "nilfs.h"14#include "segment.h"15 16int nilfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)17{18 /*19 * Called from fsync() system call20 * This is the only entry point that can catch write and synch21 * timing for both data blocks and intermediate blocks.22 *23 * This function should be implemented when the writeback function24 * will be implemented.25 */26 struct the_nilfs *nilfs;27 struct inode *inode = file->f_mapping->host;28 int err = 0;29 30 if (nilfs_inode_dirty(inode)) {31 if (datasync)32 err = nilfs_construct_dsync_segment(inode->i_sb, inode,33 start, end);34 else35 err = nilfs_construct_segment(inode->i_sb);36 }37 38 nilfs = inode->i_sb->s_fs_info;39 if (!err)40 err = nilfs_flush_device(nilfs);41 42 return err;43}44 45static vm_fault_t nilfs_page_mkwrite(struct vm_fault *vmf)46{47 struct vm_area_struct *vma = vmf->vma;48 struct folio *folio = page_folio(vmf->page);49 struct inode *inode = file_inode(vma->vm_file);50 struct nilfs_transaction_info ti;51 struct buffer_head *bh, *head;52 int ret = 0;53 54 if (unlikely(nilfs_near_disk_full(inode->i_sb->s_fs_info)))55 return VM_FAULT_SIGBUS; /* -ENOSPC */56 57 sb_start_pagefault(inode->i_sb);58 folio_lock(folio);59 if (folio->mapping != inode->i_mapping ||60 folio_pos(folio) >= i_size_read(inode) ||61 !folio_test_uptodate(folio)) {62 folio_unlock(folio);63 ret = -EFAULT; /* make the VM retry the fault */64 goto out;65 }66 67 /*68 * check to see if the folio is mapped already (no holes)69 */70 if (folio_test_mappedtodisk(folio))71 goto mapped;72 73 head = folio_buffers(folio);74 if (head) {75 int fully_mapped = 1;76 77 bh = head;78 do {79 if (!buffer_mapped(bh)) {80 fully_mapped = 0;81 break;82 }83 } while (bh = bh->b_this_page, bh != head);84 85 if (fully_mapped) {86 folio_set_mappedtodisk(folio);87 goto mapped;88 }89 }90 folio_unlock(folio);91 92 /*93 * fill hole blocks94 */95 ret = nilfs_transaction_begin(inode->i_sb, &ti, 1);96 /* never returns -ENOMEM, but may return -ENOSPC */97 if (unlikely(ret))98 goto out;99 100 file_update_time(vma->vm_file);101 ret = block_page_mkwrite(vma, vmf, nilfs_get_block);102 if (ret) {103 nilfs_transaction_abort(inode->i_sb);104 goto out;105 }106 nilfs_set_file_dirty(inode, 1 << (PAGE_SHIFT - inode->i_blkbits));107 nilfs_transaction_commit(inode->i_sb);108 109 mapped:110 /*111 * Since checksumming including data blocks is performed to determine112 * the validity of the log to be written and used for recovery, it is113 * necessary to wait for writeback to finish here, regardless of the114 * stable write requirement of the backing device.115 */116 folio_wait_writeback(folio);117 out:118 sb_end_pagefault(inode->i_sb);119 return vmf_fs_error(ret);120}121 122static const struct vm_operations_struct nilfs_file_vm_ops = {123 .fault = filemap_fault,124 .map_pages = filemap_map_pages,125 .page_mkwrite = nilfs_page_mkwrite,126};127 128static int nilfs_file_mmap(struct file *file, struct vm_area_struct *vma)129{130 file_accessed(file);131 vma->vm_ops = &nilfs_file_vm_ops;132 return 0;133}134 135/*136 * We have mostly NULL's here: the current defaults are ok for137 * the nilfs filesystem.138 */139const struct file_operations nilfs_file_operations = {140 .llseek = generic_file_llseek,141 .read_iter = generic_file_read_iter,142 .write_iter = generic_file_write_iter,143 .unlocked_ioctl = nilfs_ioctl,144#ifdef CONFIG_COMPAT145 .compat_ioctl = nilfs_compat_ioctl,146#endif /* CONFIG_COMPAT */147 .mmap = nilfs_file_mmap,148 .open = generic_file_open,149 /* .release = nilfs_release_file, */150 .fsync = nilfs_sync_file,151 .splice_read = filemap_splice_read,152 .splice_write = iter_file_splice_write,153};154 155const struct inode_operations nilfs_file_inode_operations = {156 .setattr = nilfs_setattr,157 .permission = nilfs_permission,158 .fiemap = nilfs_fiemap,159 .fileattr_get = nilfs_fileattr_get,160 .fileattr_set = nilfs_fileattr_set,161};162 163/* end of file */164