diff options
Diffstat (limited to 'fs/nilfs2/file.c')
| -rw-r--r-- | fs/nilfs2/file.c | 165 |
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 */ |