mirror of https://gitee.com/openkylin/linux.git
283 lines
6.7 KiB
C
283 lines
6.7 KiB
C
/*
|
|
* file.c
|
|
*
|
|
* PURPOSE
|
|
* File handling routines for the OSTA-UDF(tm) filesystem.
|
|
*
|
|
* COPYRIGHT
|
|
* This file is distributed under the terms of the GNU General Public
|
|
* License (GPL). Copies of the GPL can be obtained from:
|
|
* ftp://prep.ai.mit.edu/pub/gnu/GPL
|
|
* Each contributing author retains all rights to their own work.
|
|
*
|
|
* (C) 1998-1999 Dave Boynton
|
|
* (C) 1998-2004 Ben Fennema
|
|
* (C) 1999-2000 Stelias Computing Inc
|
|
*
|
|
* HISTORY
|
|
*
|
|
* 10/02/98 dgb Attempt to integrate into udf.o
|
|
* 10/07/98 Switched to using generic_readpage, etc., like isofs
|
|
* And it works!
|
|
* 12/06/98 blf Added udf_file_read. uses generic_file_read for all cases but
|
|
* ICBTAG_FLAG_AD_IN_ICB.
|
|
* 04/06/99 64 bit file handling on 32 bit systems taken from ext2 file.c
|
|
* 05/12/99 Preliminary file write support
|
|
*/
|
|
|
|
#include "udfdecl.h"
|
|
#include <linux/fs.h>
|
|
#include <linux/uaccess.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/string.h> /* memset */
|
|
#include <linux/capability.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/pagemap.h>
|
|
#include <linux/uio.h>
|
|
|
|
#include "udf_i.h"
|
|
#include "udf_sb.h"
|
|
|
|
static void __udf_adinicb_readpage(struct page *page)
|
|
{
|
|
struct inode *inode = page->mapping->host;
|
|
char *kaddr;
|
|
struct udf_inode_info *iinfo = UDF_I(inode);
|
|
|
|
kaddr = kmap(page);
|
|
memcpy(kaddr, iinfo->i_ext.i_data + iinfo->i_lenEAttr, inode->i_size);
|
|
memset(kaddr + inode->i_size, 0, PAGE_SIZE - inode->i_size);
|
|
flush_dcache_page(page);
|
|
SetPageUptodate(page);
|
|
kunmap(page);
|
|
}
|
|
|
|
static int udf_adinicb_readpage(struct file *file, struct page *page)
|
|
{
|
|
BUG_ON(!PageLocked(page));
|
|
__udf_adinicb_readpage(page);
|
|
unlock_page(page);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int udf_adinicb_writepage(struct page *page,
|
|
struct writeback_control *wbc)
|
|
{
|
|
struct inode *inode = page->mapping->host;
|
|
char *kaddr;
|
|
struct udf_inode_info *iinfo = UDF_I(inode);
|
|
|
|
BUG_ON(!PageLocked(page));
|
|
|
|
kaddr = kmap(page);
|
|
memcpy(iinfo->i_ext.i_data + iinfo->i_lenEAttr, kaddr, inode->i_size);
|
|
mark_inode_dirty(inode);
|
|
SetPageUptodate(page);
|
|
kunmap(page);
|
|
unlock_page(page);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int udf_adinicb_write_begin(struct file *file,
|
|
struct address_space *mapping, loff_t pos,
|
|
unsigned len, unsigned flags, struct page **pagep,
|
|
void **fsdata)
|
|
{
|
|
struct page *page;
|
|
|
|
if (WARN_ON_ONCE(pos >= PAGE_SIZE))
|
|
return -EIO;
|
|
page = grab_cache_page_write_begin(mapping, 0, flags);
|
|
if (!page)
|
|
return -ENOMEM;
|
|
*pagep = page;
|
|
|
|
if (!PageUptodate(page))
|
|
__udf_adinicb_readpage(page);
|
|
return 0;
|
|
}
|
|
|
|
static ssize_t udf_adinicb_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
|
|
{
|
|
/* Fallback to buffered I/O. */
|
|
return 0;
|
|
}
|
|
|
|
static int udf_adinicb_write_end(struct file *file, struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned copied,
|
|
struct page *page, void *fsdata)
|
|
{
|
|
struct inode *inode = page->mapping->host;
|
|
loff_t last_pos = pos + copied;
|
|
if (last_pos > inode->i_size)
|
|
i_size_write(inode, last_pos);
|
|
set_page_dirty(page);
|
|
unlock_page(page);
|
|
put_page(page);
|
|
return copied;
|
|
}
|
|
|
|
const struct address_space_operations udf_adinicb_aops = {
|
|
.readpage = udf_adinicb_readpage,
|
|
.writepage = udf_adinicb_writepage,
|
|
.write_begin = udf_adinicb_write_begin,
|
|
.write_end = udf_adinicb_write_end,
|
|
.direct_IO = udf_adinicb_direct_IO,
|
|
};
|
|
|
|
static ssize_t udf_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
|
|
{
|
|
ssize_t retval;
|
|
struct file *file = iocb->ki_filp;
|
|
struct inode *inode = file_inode(file);
|
|
struct udf_inode_info *iinfo = UDF_I(inode);
|
|
int err;
|
|
|
|
inode_lock(inode);
|
|
|
|
retval = generic_write_checks(iocb, from);
|
|
if (retval <= 0)
|
|
goto out;
|
|
|
|
down_write(&iinfo->i_data_sem);
|
|
if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
|
|
loff_t end = iocb->ki_pos + iov_iter_count(from);
|
|
|
|
if (inode->i_sb->s_blocksize <
|
|
(udf_file_entry_alloc_offset(inode) + end)) {
|
|
err = udf_expand_file_adinicb(inode);
|
|
if (err) {
|
|
inode_unlock(inode);
|
|
udf_debug("udf_expand_adinicb: err=%d\n", err);
|
|
return err;
|
|
}
|
|
} else {
|
|
iinfo->i_lenAlloc = max(end, inode->i_size);
|
|
up_write(&iinfo->i_data_sem);
|
|
}
|
|
} else
|
|
up_write(&iinfo->i_data_sem);
|
|
|
|
retval = __generic_file_write_iter(iocb, from);
|
|
out:
|
|
inode_unlock(inode);
|
|
|
|
if (retval > 0) {
|
|
mark_inode_dirty(inode);
|
|
retval = generic_write_sync(iocb, retval);
|
|
}
|
|
|
|
return retval;
|
|
}
|
|
|
|
long udf_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
|
|
{
|
|
struct inode *inode = file_inode(filp);
|
|
long old_block, new_block;
|
|
int result = -EINVAL;
|
|
|
|
if (inode_permission(inode, MAY_READ) != 0) {
|
|
udf_debug("no permission to access inode %lu\n", inode->i_ino);
|
|
result = -EPERM;
|
|
goto out;
|
|
}
|
|
|
|
if (!arg) {
|
|
udf_debug("invalid argument to udf_ioctl\n");
|
|
result = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
switch (cmd) {
|
|
case UDF_GETVOLIDENT:
|
|
if (copy_to_user((char __user *)arg,
|
|
UDF_SB(inode->i_sb)->s_volume_ident, 32))
|
|
result = -EFAULT;
|
|
else
|
|
result = 0;
|
|
goto out;
|
|
case UDF_RELOCATE_BLOCKS:
|
|
if (!capable(CAP_SYS_ADMIN)) {
|
|
result = -EPERM;
|
|
goto out;
|
|
}
|
|
if (get_user(old_block, (long __user *)arg)) {
|
|
result = -EFAULT;
|
|
goto out;
|
|
}
|
|
result = udf_relocate_blocks(inode->i_sb,
|
|
old_block, &new_block);
|
|
if (result == 0)
|
|
result = put_user(new_block, (long __user *)arg);
|
|
goto out;
|
|
case UDF_GETEASIZE:
|
|
result = put_user(UDF_I(inode)->i_lenEAttr, (int __user *)arg);
|
|
goto out;
|
|
case UDF_GETEABLOCK:
|
|
result = copy_to_user((char __user *)arg,
|
|
UDF_I(inode)->i_ext.i_data,
|
|
UDF_I(inode)->i_lenEAttr) ? -EFAULT : 0;
|
|
goto out;
|
|
}
|
|
|
|
out:
|
|
return result;
|
|
}
|
|
|
|
static int udf_release_file(struct inode *inode, struct file *filp)
|
|
{
|
|
if (filp->f_mode & FMODE_WRITE &&
|
|
atomic_read(&inode->i_writecount) == 1) {
|
|
/*
|
|
* Grab i_mutex to avoid races with writes changing i_size
|
|
* while we are running.
|
|
*/
|
|
inode_lock(inode);
|
|
down_write(&UDF_I(inode)->i_data_sem);
|
|
udf_discard_prealloc(inode);
|
|
udf_truncate_tail_extent(inode);
|
|
up_write(&UDF_I(inode)->i_data_sem);
|
|
inode_unlock(inode);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
const struct file_operations udf_file_operations = {
|
|
.read_iter = generic_file_read_iter,
|
|
.unlocked_ioctl = udf_ioctl,
|
|
.open = generic_file_open,
|
|
.mmap = generic_file_mmap,
|
|
.write_iter = udf_file_write_iter,
|
|
.release = udf_release_file,
|
|
.fsync = generic_file_fsync,
|
|
.splice_read = generic_file_splice_read,
|
|
.llseek = generic_file_llseek,
|
|
};
|
|
|
|
static int udf_setattr(struct dentry *dentry, struct iattr *attr)
|
|
{
|
|
struct inode *inode = d_inode(dentry);
|
|
int error;
|
|
|
|
error = setattr_prepare(dentry, attr);
|
|
if (error)
|
|
return error;
|
|
|
|
if ((attr->ia_valid & ATTR_SIZE) &&
|
|
attr->ia_size != i_size_read(inode)) {
|
|
error = udf_setsize(inode, attr->ia_size);
|
|
if (error)
|
|
return error;
|
|
}
|
|
|
|
setattr_copy(inode, attr);
|
|
mark_inode_dirty(inode);
|
|
return 0;
|
|
}
|
|
|
|
const struct inode_operations udf_file_inode_operations = {
|
|
.setattr = udf_setattr,
|
|
};
|