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/*
* file.c
*
* PURPOSE
* File handling routines for the OSTA-UDF(tm) filesystem.
*
* CONTACTS
* E-mail regarding any portion of the Linux UDF file system should be
* directed to the development team mailing list (run by majordomo):
* linux_udf@hpesjro.fc.hp.com
*
* 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) 1998-2000 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
* ICB_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/udf_fs.h>
#include <asm/uaccess.h>
#include <linux/kernel.h>
#include <linux/string.h> /* memset */
#include <linux/errno.h>
#include <linux/locks.h>
#include <linux/smp_lock.h>
#include "udf_i.h"
#include "udf_sb.h"
static int udf_adinicb_readpage(struct file *file, struct page * page)
{
struct inode *inode = page->mapping->host;
struct buffer_head *bh;
int block;
char *kaddr;
if (!PageLocked(page))
PAGE_BUG(page);
kaddr = kmap(page);
memset(kaddr, 0, PAGE_CACHE_SIZE);
block = udf_get_lb_pblock(inode->i_sb, UDF_I_LOCATION(inode), 0);
bh = sb_bread(inode->i_sb, block);
memcpy(kaddr, bh->b_data + udf_ext0_offset(inode), inode->i_size);
brelse(bh);
flush_dcache_page(page);
SetPageUptodate(page);
kunmap(page);
UnlockPage(page);
return 0;
}
static int udf_adinicb_writepage(struct page *page)
{
struct inode *inode = page->mapping->host;
struct buffer_head *bh;
int block;
char *kaddr;
if (!PageLocked(page))
PAGE_BUG(page);
kaddr = kmap(page);
block = udf_get_lb_pblock(inode->i_sb, UDF_I_LOCATION(inode), 0);
bh = sb_bread(inode->i_sb, block);
memcpy(bh->b_data + udf_ext0_offset(inode), kaddr, inode->i_size);
mark_buffer_dirty(bh);
brelse(bh);
SetPageUptodate(page);
kunmap(page);
UnlockPage(page);
return 0;
}
static int udf_adinicb_prepare_write(struct file *file, struct page *page, unsigned offset, unsigned to)
{
kmap(page);
return 0;
}
static int udf_adinicb_commit_write(struct file *file, struct page *page, unsigned offset, unsigned to)
{
struct inode *inode = page->mapping->host;
struct buffer_head *bh;
int block;
char *kaddr = page_address(page);
block = udf_get_lb_pblock(inode->i_sb, UDF_I_LOCATION(inode), 0);
bh = sb_bread(inode->i_sb, block);
memcpy(bh->b_data + udf_file_entry_alloc_offset(inode) + offset,
kaddr + offset, to-offset);
mark_buffer_dirty(bh);
brelse(bh);
SetPageUptodate(page);
kunmap(page);
/* only one page here */
if (to > inode->i_size)
inode->i_size = to;
return 0;
}
struct address_space_operations udf_adinicb_aops = {
readpage: udf_adinicb_readpage,
writepage: udf_adinicb_writepage,
sync_page: block_sync_page,
prepare_write: udf_adinicb_prepare_write,
commit_write: udf_adinicb_commit_write,
};
static ssize_t udf_file_write(struct file * file, const char * buf,
size_t count, loff_t *ppos)
{
ssize_t retval;
struct inode *inode = file->f_dentry->d_inode;
int err, pos;
if (UDF_I_ALLOCTYPE(inode) == ICB_FLAG_AD_IN_ICB)
{
if (file->f_flags & O_APPEND)
pos = inode->i_size;
else
pos = *ppos;
if (inode->i_sb->s_blocksize < (udf_file_entry_alloc_offset(inode) +
pos + count))
{
udf_expand_file_adinicb(inode, pos + count, &err);
if (UDF_I_ALLOCTYPE(inode) == ICB_FLAG_AD_IN_ICB)
{
udf_debug("udf_expand_adinicb: err=%d\n", err);
return err;
}
}
else
{
if (pos + count > inode->i_size)
UDF_I_LENALLOC(inode) = pos + count;
else
UDF_I_LENALLOC(inode) = inode->i_size;
}
}
retval = generic_file_write(file, buf, count, ppos);
if (retval > 0)
{
UDF_I_UCTIME(inode) = UDF_I_UMTIME(inode) = CURRENT_UTIME;
mark_inode_dirty(inode);
}
return retval;
}
/*
* udf_ioctl
*
* PURPOSE
* Issue an ioctl.
*
* DESCRIPTION
* Optional - sys_ioctl() will return -ENOTTY if this routine is not
* available, and the ioctl cannot be handled without filesystem help.
*
* sys_ioctl() handles these ioctls that apply only to regular files:
* FIBMAP [requires udf_block_map()], FIGETBSZ, FIONREAD
* These ioctls are also handled by sys_ioctl():
* FIOCLEX, FIONCLEX, FIONBIO, FIOASYNC
* All other ioctls are passed to the filesystem.
*
* Refer to sys_ioctl() in fs/ioctl.c
* sys_ioctl() -> .
*
* PRE-CONDITIONS
* inode Pointer to inode that ioctl was issued on.
* filp Pointer to file that ioctl was issued on.
* cmd The ioctl command.
* arg The ioctl argument [can be interpreted as a
* user-space pointer if desired].
*
* POST-CONDITIONS
* <return> Success (>=0) or an error code (<=0) that
* sys_ioctl() will return.
*
* HISTORY
* July 1, 1997 - Andrew E. Mileski
* Written, tested, and released.
*/
int udf_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
unsigned long arg)
{
int result = -EINVAL;
struct buffer_head *bh = NULL;
long_ad eaicb;
Uint8 *ea = NULL;
if ( permission(inode, MAY_READ) != 0 )
{
udf_debug("no permission to access inode %lu\n",
inode->i_ino);
return -EPERM;
}
if ( !arg )
{
udf_debug("invalid argument to udf_ioctl\n");
return -EINVAL;
}
/* first, do ioctls that don't need to udf_read */
switch (cmd)
{
case UDF_GETVOLIDENT:
return copy_to_user((char *)arg,
UDF_SB_VOLIDENT(inode->i_sb), 32) ? -EFAULT : 0;
case UDF_RELOCATE_BLOCKS:
{
long old, new;
if (!capable(CAP_SYS_ADMIN)) return -EACCES;
if (get_user(old, (long *)arg)) return -EFAULT;
if ((result = udf_relocate_blocks(inode->i_sb,
old, &new)) == 0)
result = put_user(new, (long *)arg);
return result;
}
}
/* ok, we need to read the inode */
bh = udf_tread(inode->i_sb,
udf_get_lb_pblock(inode->i_sb, UDF_I_LOCATION(inode), 0));
if (!bh)
{
udf_debug("bread failed (inode=%ld)\n", inode->i_ino);
return -EIO;
}
if (UDF_I_EXTENDED_FE(inode) == 0)
{
struct FileEntry *fe;
fe = (struct FileEntry *)bh->b_data;
eaicb = lela_to_cpu(fe->extendedAttrICB);
if (UDF_I_LENEATTR(inode))
ea = fe->extendedAttr;
}
else
{
struct ExtendedFileEntry *efe;
efe = (struct ExtendedFileEntry *)bh->b_data;
eaicb = lela_to_cpu(efe->extendedAttrICB);
if (UDF_I_LENEATTR(inode))
ea = efe->extendedAttr;
}
switch (cmd)
{
case UDF_GETEASIZE:
result = put_user(UDF_I_LENEATTR(inode), (int *)arg);
break;
case UDF_GETEABLOCK:
result = copy_to_user((char *)arg, ea,
UDF_I_LENEATTR(inode)) ? -EFAULT : 0;
break;
}
udf_release_data(bh);
return result;
}
/*
* udf_release_file
*
* PURPOSE
* Called when all references to the file are closed
*
* DESCRIPTION
* Discard prealloced blocks
*
* HISTORY
*
*/
static int udf_release_file(struct inode * inode, struct file * filp)
{
if (filp->f_mode & FMODE_WRITE)
{
lock_kernel();
udf_discard_prealloc(inode);
unlock_kernel();
}
return 0;
}
/*
* udf_open_file
*
* PURPOSE
* Called when an inode is about to be open.
*
* DESCRIPTION
* Use this to disallow opening RW large files on 32 bit systems.
* On 64 bit systems we force on O_LARGEFILE in sys_open.
*
* HISTORY
*
*/
static int udf_open_file(struct inode * inode, struct file * filp)
{
if ((inode->i_size & 0xFFFFFFFF80000000ULL) && !(filp->f_flags & O_LARGEFILE))
return -EFBIG;
return 0;
}
struct file_operations udf_file_operations = {
read: generic_file_read,
ioctl: udf_ioctl,
open: udf_open_file,
mmap: generic_file_mmap,
write: udf_file_write,
release: udf_release_file,
fsync: udf_fsync_file,
};
struct inode_operations udf_file_inode_operations = {
truncate: udf_truncate,
};
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