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-rw-r--r--fs/nilfs2/file.c165
1 files changed, 165 insertions, 0 deletions
diff --git a/fs/nilfs2/file.c b/fs/nilfs2/file.c
new file mode 100644
index 000000000..54575e3cc
--- /dev/null
+++ b/fs/nilfs2/file.c
@@ -0,0 +1,165 @@
+/*
+ * file.c - NILFS regular file handling primitives including fsync().
+ *
+ * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Written by Amagai Yoshiji <amagai@osrg.net>,
+ * Ryusuke Konishi <ryusuke@osrg.net>
+ */
+
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/writeback.h>
+#include "nilfs.h"
+#include "segment.h"
+
+int nilfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
+{
+ /*
+ * Called from fsync() system call
+ * This is the only entry point that can catch write and synch
+ * timing for both data blocks and intermediate blocks.
+ *
+ * This function should be implemented when the writeback function
+ * will be implemented.
+ */
+ struct the_nilfs *nilfs;
+ struct inode *inode = file->f_mapping->host;
+ int err = 0;
+
+ if (nilfs_inode_dirty(inode)) {
+ if (datasync)
+ err = nilfs_construct_dsync_segment(inode->i_sb, inode,
+ start, end);
+ else
+ err = nilfs_construct_segment(inode->i_sb);
+ }
+
+ nilfs = inode->i_sb->s_fs_info;
+ if (!err)
+ err = nilfs_flush_device(nilfs);
+
+ return err;
+}
+
+static int nilfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+ struct page *page = vmf->page;
+ struct inode *inode = file_inode(vma->vm_file);
+ struct nilfs_transaction_info ti;
+ int ret = 0;
+
+ if (unlikely(nilfs_near_disk_full(inode->i_sb->s_fs_info)))
+ return VM_FAULT_SIGBUS; /* -ENOSPC */
+
+ sb_start_pagefault(inode->i_sb);
+ lock_page(page);
+ if (page->mapping != inode->i_mapping ||
+ page_offset(page) >= i_size_read(inode) || !PageUptodate(page)) {
+ unlock_page(page);
+ ret = -EFAULT; /* make the VM retry the fault */
+ goto out;
+ }
+
+ /*
+ * check to see if the page is mapped already (no holes)
+ */
+ if (PageMappedToDisk(page))
+ goto mapped;
+
+ if (page_has_buffers(page)) {
+ struct buffer_head *bh, *head;
+ int fully_mapped = 1;
+
+ bh = head = page_buffers(page);
+ do {
+ if (!buffer_mapped(bh)) {
+ fully_mapped = 0;
+ break;
+ }
+ } while (bh = bh->b_this_page, bh != head);
+
+ if (fully_mapped) {
+ SetPageMappedToDisk(page);
+ goto mapped;
+ }
+ }
+ unlock_page(page);
+
+ /*
+ * fill hole blocks
+ */
+ ret = nilfs_transaction_begin(inode->i_sb, &ti, 1);
+ /* never returns -ENOMEM, but may return -ENOSPC */
+ if (unlikely(ret))
+ goto out;
+
+ file_update_time(vma->vm_file);
+ ret = __block_page_mkwrite(vma, vmf, nilfs_get_block);
+ if (ret) {
+ nilfs_transaction_abort(inode->i_sb);
+ goto out;
+ }
+ nilfs_set_file_dirty(inode, 1 << (PAGE_SHIFT - inode->i_blkbits));
+ nilfs_transaction_commit(inode->i_sb);
+
+ mapped:
+ wait_for_stable_page(page);
+ out:
+ sb_end_pagefault(inode->i_sb);
+ return block_page_mkwrite_return(ret);
+}
+
+static const struct vm_operations_struct nilfs_file_vm_ops = {
+ .fault = filemap_fault,
+ .map_pages = filemap_map_pages,
+ .page_mkwrite = nilfs_page_mkwrite,
+};
+
+static int nilfs_file_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ file_accessed(file);
+ vma->vm_ops = &nilfs_file_vm_ops;
+ return 0;
+}
+
+/*
+ * We have mostly NULL's here: the current defaults are ok for
+ * the nilfs filesystem.
+ */
+const struct file_operations nilfs_file_operations = {
+ .llseek = generic_file_llseek,
+ .read_iter = generic_file_read_iter,
+ .write_iter = generic_file_write_iter,
+ .unlocked_ioctl = nilfs_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = nilfs_compat_ioctl,
+#endif /* CONFIG_COMPAT */
+ .mmap = nilfs_file_mmap,
+ .open = generic_file_open,
+ /* .release = nilfs_release_file, */
+ .fsync = nilfs_sync_file,
+ .splice_read = generic_file_splice_read,
+};
+
+const struct inode_operations nilfs_file_inode_operations = {
+ .setattr = nilfs_setattr,
+ .permission = nilfs_permission,
+ .fiemap = nilfs_fiemap,
+};
+
+/* end of file */