diff options
Diffstat (limited to 'fs/sdcardfs/mmap.c')
-rw-r--r-- | fs/sdcardfs/mmap.c | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/fs/sdcardfs/mmap.c b/fs/sdcardfs/mmap.c new file mode 100644 index 000000000000..b61f82275e7d --- /dev/null +++ b/fs/sdcardfs/mmap.c @@ -0,0 +1,89 @@ +/* + * fs/sdcardfs/mmap.c + * + * Copyright (c) 2013 Samsung Electronics Co. Ltd + * Authors: Daeho Jeong, Woojoong Lee, Seunghwan Hyun, + * Sunghwan Yun, Sungjong Seo + * + * This program has been developed as a stackable file system based on + * the WrapFS which written by + * + * Copyright (c) 1998-2011 Erez Zadok + * Copyright (c) 2009 Shrikar Archak + * Copyright (c) 2003-2011 Stony Brook University + * Copyright (c) 2003-2011 The Research Foundation of SUNY + * + * This file is dual licensed. It may be redistributed and/or modified + * under the terms of the Apache 2.0 License OR version 2 of the GNU + * General Public License. + */ + +#include "sdcardfs.h" + +static int sdcardfs_fault(struct vm_area_struct *vma, struct vm_fault *vmf) +{ + int err; + struct file *file; + const struct vm_operations_struct *lower_vm_ops; + + file = (struct file *)vma->vm_private_data; + lower_vm_ops = SDCARDFS_F(file)->lower_vm_ops; + BUG_ON(!lower_vm_ops); + + err = lower_vm_ops->fault(vma, vmf); + return err; +} + +static void sdcardfs_vm_open(struct vm_area_struct *vma) +{ + struct file *file = (struct file *)vma->vm_private_data; + + get_file(file); +} + +static void sdcardfs_vm_close(struct vm_area_struct *vma) +{ + struct file *file = (struct file *)vma->vm_private_data; + + fput(file); +} + +static int sdcardfs_page_mkwrite(struct vm_area_struct *vma, + struct vm_fault *vmf) +{ + int err = 0; + struct file *file; + const struct vm_operations_struct *lower_vm_ops; + + file = (struct file *)vma->vm_private_data; + lower_vm_ops = SDCARDFS_F(file)->lower_vm_ops; + BUG_ON(!lower_vm_ops); + if (!lower_vm_ops->page_mkwrite) + goto out; + + err = lower_vm_ops->page_mkwrite(vma, vmf); +out: + return err; +} + +static ssize_t sdcardfs_direct_IO(struct kiocb *iocb, + struct iov_iter *iter, loff_t pos) +{ + /* + * This function should never be called directly. We need it + * to exist, to get past a check in open_check_o_direct(), + * which is called from do_last(). + */ + return -EINVAL; +} + +const struct address_space_operations sdcardfs_aops = { + .direct_IO = sdcardfs_direct_IO, +}; + +const struct vm_operations_struct sdcardfs_vm_ops = { + .fault = sdcardfs_fault, + .page_mkwrite = sdcardfs_page_mkwrite, + .open = sdcardfs_vm_open, + .close = sdcardfs_vm_close, +}; |