diff options
Diffstat (limited to 'fs/nilfs2/file.c')
| -rw-r--r-- | fs/nilfs2/file.c | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/fs/nilfs2/file.c b/fs/nilfs2/file.c new file mode 100644 index 000000000000..6bd84a0d8238 --- /dev/null +++ b/fs/nilfs2/file.c @@ -0,0 +1,160 @@ +/* + * 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, struct dentry *dentry, 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 inode *inode = dentry->d_inode; + int err; + + if (!nilfs_inode_dirty(inode)) + return 0; + + if (datasync) + err = nilfs_construct_dsync_segment(inode->i_sb, inode, 0, + LLONG_MAX); + else + err = nilfs_construct_segment(inode->i_sb); + + return err; +} + +static int nilfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) +{ + struct page *page = vmf->page; + struct inode *inode = vma->vm_file->f_dentry->d_inode; + struct nilfs_transaction_info ti; + int ret; + + if (unlikely(nilfs_near_disk_full(NILFS_SB(inode->i_sb)->s_nilfs))) + return VM_FAULT_SIGBUS; /* -ENOSPC */ + + lock_page(page); + if (page->mapping != inode->i_mapping || + page_offset(page) >= i_size_read(inode) || !PageUptodate(page)) { + unlock_page(page); + return VM_FAULT_NOPAGE; /* make the VM retry the fault */ + } + + /* + * check to see if the page is mapped already (no holes) + */ + if (PageMappedToDisk(page)) { + unlock_page(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); + unlock_page(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)) + return VM_FAULT_SIGBUS; + + ret = block_page_mkwrite(vma, vmf, nilfs_get_block); + if (unlikely(ret)) { + nilfs_transaction_abort(inode->i_sb); + return ret; + } + nilfs_transaction_commit(inode->i_sb); + + mapped: + SetPageChecked(page); + wait_on_page_writeback(page); + return 0; +} + +struct vm_operations_struct nilfs_file_vm_ops = { + .fault = filemap_fault, + .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; + vma->vm_flags |= VM_CAN_NONLINEAR; + return 0; +} + +/* + * We have mostly NULL's here: the current defaults are ok for + * the nilfs filesystem. + */ +struct file_operations nilfs_file_operations = { + .llseek = generic_file_llseek, + .read = do_sync_read, + .write = do_sync_write, + .aio_read = generic_file_aio_read, + .aio_write = generic_file_aio_write, + .unlocked_ioctl = nilfs_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = nilfs_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, +}; + +struct inode_operations nilfs_file_inode_operations = { + .truncate = nilfs_truncate, + .setattr = nilfs_setattr, + .permission = nilfs_permission, +}; + +/* end of file */ |