[mirror_ubuntu-zesty-kernel.git] / fs / udf / file.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/udf_fs.h>
#include <asm/uaccess.h>
#include <linux/kernel.h>
#include <linux/string.h> /* memset */
#include <linux/capability.h>
#include <linux/errno.h>
#include <linux/smp_lock.h>
#include <linux/pagemap.h>
#include <linux/buffer_head.h>
#include <linux/aio.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;
	char *kaddr;

	BUG_ON(!PageLocked(page));

	kaddr = kmap(page);
	memset(kaddr, 0, PAGE_CACHE_SIZE);
	memcpy(kaddr, UDF_I_DATA(inode) + UDF_I_LENEATTR(inode), inode->i_size);
	flush_dcache_page(page);
	SetPageUptodate(page);
	kunmap(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;

	BUG_ON(!PageLocked(page));

	kaddr = kmap(page);
	memcpy(UDF_I_DATA(inode) + UDF_I_LENEATTR(inode), kaddr, inode->i_size);
	mark_inode_dirty(inode);
	SetPageUptodate(page);
	kunmap(page);
	unlock_page(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;
	char *kaddr = page_address(page);

	memcpy(UDF_I_DATA(inode) + UDF_I_LENEATTR(inode) + offset,
		kaddr + offset, to - offset);
	mark_inode_dirty(inode);
	SetPageUptodate(page);
	kunmap(page);
	/* only one page here */
	if (to > inode->i_size)
		inode->i_size = to;
	return 0;
}

const 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_aio_write(struct kiocb *iocb, const struct iovec *iov,
			      unsigned long nr_segs, loff_t ppos)
{
	ssize_t retval;
	struct file *file = iocb->ki_filp;
	struct inode *inode = file->f_path.dentry->d_inode;
	int err, pos;
	size_t count = iocb->ki_left;

	if (UDF_I_ALLOCTYPE(inode) == ICBTAG_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) == ICBTAG_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_aio_write(iocb, iov, nr_segs, ppos);

	if (retval > 0)
		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;

	if ( file_permission(filp, 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;
	}

	switch (cmd)
	{
		case UDF_GETVOLIDENT:
			return copy_to_user((char __user *)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 __user *)arg)) return -EFAULT;
			if ((result = udf_relocate_blocks(inode->i_sb,
					old, &new)) == 0)
				result = put_user(new, (long __user *)arg);

			return result;
		}
		case UDF_GETEASIZE:
			result = put_user(UDF_I_LENEATTR(inode), (int __user *)arg);
			break;

		case UDF_GETEABLOCK:
			result = copy_to_user((char __user *)arg, UDF_I_DATA(inode),
				UDF_I_LENEATTR(inode)) ? -EFAULT : 0;
			break;
	}

	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;
}

const struct file_operations udf_file_operations = {
	.read			= do_sync_read,
	.aio_read		= generic_file_aio_read,
	.ioctl			= udf_ioctl,
	.open			= generic_file_open,
	.mmap			= generic_file_mmap,
	.write			= do_sync_write,
	.aio_write		= udf_file_aio_write,
	.release		= udf_release_file,
	.fsync			= udf_fsync_file,
	.splice_read		= generic_file_splice_read,
};

const struct inode_operations udf_file_inode_operations = {
	.truncate		= udf_truncate,
};
Commit	Line	Data
1da177e4 LT	1	/*
	2	* file.c
	3	*
	4	* PURPOSE
	5	* File handling routines for the OSTA-UDF(tm) filesystem.
	6	*
1da177e4 LT	7	* COPYRIGHT
	8	* This file is distributed under the terms of the GNU General Public
	9	* License (GPL). Copies of the GPL can be obtained from:
	10	* ftp://prep.ai.mit.edu/pub/gnu/GPL
	11	* Each contributing author retains all rights to their own work.
	12	*
	13	* (C) 1998-1999 Dave Boynton
	14	* (C) 1998-2004 Ben Fennema
	15	* (C) 1999-2000 Stelias Computing Inc
	16	*
	17	* HISTORY
	18	*
	19	* 10/02/98 dgb Attempt to integrate into udf.o
	20	* 10/07/98 Switched to using generic_readpage, etc., like isofs
	21	* And it works!
	22	* 12/06/98 blf Added udf_file_read. uses generic_file_read for all cases but
	23	* ICBTAG_FLAG_AD_IN_ICB.
	24	* 04/06/99 64 bit file handling on 32 bit systems taken from ext2 file.c
	25	* 05/12/99 Preliminary file write support
	26	*/
	27
	28	#include "udfdecl.h"
	29	#include <linux/fs.h>
	30	#include <linux/udf_fs.h>
	31	#include <asm/uaccess.h>
	32	#include <linux/kernel.h>
	33	#include <linux/string.h> /* memset */
16f7e0fe	34	#include <linux/capability.h>
1da177e4 LT	35	#include <linux/errno.h>
	36	#include <linux/smp_lock.h>
	37	#include <linux/pagemap.h>
	38	#include <linux/buffer_head.h>
e8edc6e0	39	#include <linux/aio.h>
1da177e4 LT	40
	41	#include "udf_i.h"
	42	#include "udf_sb.h"
	43
	44	static int udf_adinicb_readpage(struct file file, struct page page)
	45	{
	46	struct inode *inode = page->mapping->host;
	47	char *kaddr;
	48
cd7619d6	49	BUG_ON(!PageLocked(page));
1da177e4 LT	50
	51	kaddr = kmap(page);
	52	memset(kaddr, 0, PAGE_CACHE_SIZE);
	53	memcpy(kaddr, UDF_I_DATA(inode) + UDF_I_LENEATTR(inode), inode->i_size);
	54	flush_dcache_page(page);
	55	SetPageUptodate(page);
	56	kunmap(page);
	57	unlock_page(page);
	58	return 0;
	59	}
	60
	61	static int udf_adinicb_writepage(struct page page, struct writeback_control wbc)
	62	{
	63	struct inode *inode = page->mapping->host;
	64	char *kaddr;
	65
cd7619d6	66	BUG_ON(!PageLocked(page));
1da177e4 LT	67
	68	kaddr = kmap(page);
	69	memcpy(UDF_I_DATA(inode) + UDF_I_LENEATTR(inode), kaddr, inode->i_size);
	70	mark_inode_dirty(inode);
	71	SetPageUptodate(page);
	72	kunmap(page);
	73	unlock_page(page);
	74	return 0;
	75	}
	76
	77	static int udf_adinicb_prepare_write(struct file file, struct page page, unsigned offset, unsigned to)
	78	{
	79	kmap(page);
	80	return 0;
	81	}
	82
	83	static int udf_adinicb_commit_write(struct file file, struct page page, unsigned offset, unsigned to)
	84	{
	85	struct inode *inode = page->mapping->host;
	86	char *kaddr = page_address(page);
	87
	88	memcpy(UDF_I_DATA(inode) + UDF_I_LENEATTR(inode) + offset,
	89	kaddr + offset, to - offset);
	90	mark_inode_dirty(inode);
	91	SetPageUptodate(page);
	92	kunmap(page);
	93	/* only one page here */
	94	if (to > inode->i_size)
	95	inode->i_size = to;
	96	return 0;
	97	}
	98
f5e54d6e	99	const struct address_space_operations udf_adinicb_aops = {
1da177e4 LT	100	.readpage = udf_adinicb_readpage,
	101	.writepage = udf_adinicb_writepage,
	102	.sync_page = block_sync_page,
	103	.prepare_write = udf_adinicb_prepare_write,
	104	.commit_write = udf_adinicb_commit_write,
	105	};
	106
543ade1f BP	107	static ssize_t udf_file_aio_write(struct kiocb iocb, const struct iovec iov,
543ade1f BP	108	unsigned long nr_segs, loff_t ppos)
1da177e4 LT	109	{
1da177e4 LT	110	ssize_t retval;
543ade1f	111	struct file *file = iocb->ki_filp;
5096e933	112	struct inode *inode = file->f_path.dentry->d_inode;
1da177e4	113	int err, pos;
543ade1f	114	size_t count = iocb->ki_left;
1da177e4 LT	115
	116	if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_IN_ICB)
	117	{
	118	if (file->f_flags & O_APPEND)
	119	pos = inode->i_size;
	120	else
543ade1f	121	pos = ppos;
1da177e4 LT	122
	123	if (inode->i_sb->s_blocksize < (udf_file_entry_alloc_offset(inode) +
	124	pos + count))
	125	{
	126	udf_expand_file_adinicb(inode, pos + count, &err);
	127	if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_IN_ICB)
	128	{
	129	udf_debug("udf_expand_adinicb: err=%d\n", err);
	130	return err;
	131	}
	132	}
	133	else
	134	{
	135	if (pos + count > inode->i_size)
	136	UDF_I_LENALLOC(inode) = pos + count;
	137	else
	138	UDF_I_LENALLOC(inode) = inode->i_size;
	139	}
	140	}
	141
543ade1f	142	retval = generic_file_aio_write(iocb, iov, nr_segs, ppos);
1da177e4 LT	143
	144	if (retval > 0)
	145	mark_inode_dirty(inode);
	146	return retval;
	147	}
	148
	149	/*
	150	* udf_ioctl
	151	*
	152	* PURPOSE
	153	* Issue an ioctl.
	154	*
	155	* DESCRIPTION
	156	* Optional - sys_ioctl() will return -ENOTTY if this routine is not
	157	* available, and the ioctl cannot be handled without filesystem help.
	158	*
	159	* sys_ioctl() handles these ioctls that apply only to regular files:
	160	* FIBMAP [requires udf_block_map()], FIGETBSZ, FIONREAD
	161	* These ioctls are also handled by sys_ioctl():
	162	* FIOCLEX, FIONCLEX, FIONBIO, FIOASYNC
	163	* All other ioctls are passed to the filesystem.
	164	*
	165	* Refer to sys_ioctl() in fs/ioctl.c
	166	* sys_ioctl() -> .
	167	*
	168	* PRE-CONDITIONS
	169	* inode Pointer to inode that ioctl was issued on.
	170	* filp Pointer to file that ioctl was issued on.
	171	* cmd The ioctl command.
	172	* arg The ioctl argument [can be interpreted as a
	173	* user-space pointer if desired].
	174	*
	175	* POST-CONDITIONS
	176	* <return> Success (>=0) or an error code (<=0) that
	177	* sys_ioctl() will return.
	178	*
	179	* HISTORY
	180	* July 1, 1997 - Andrew E. Mileski
	181	* Written, tested, and released.
	182	*/
	183	int udf_ioctl(struct inode inode, struct file filp, unsigned int cmd,
	184	unsigned long arg)
	185	{
	186	int result = -EINVAL;
	187
8c744fb8	188	if ( file_permission(filp, MAY_READ) != 0 )
1da177e4 LT	189	{
	190	udf_debug("no permission to access inode %lu\n",
	191	inode->i_ino);
	192	return -EPERM;
	193	}
	194
	195	if ( !arg )
	196	{
	197	udf_debug("invalid argument to udf_ioctl\n");
	198	return -EINVAL;
	199	}
	200
	201	switch (cmd)
	202	{
	203	case UDF_GETVOLIDENT:
	204	return copy_to_user((char __user *)arg,
	205	UDF_SB_VOLIDENT(inode->i_sb), 32) ? -EFAULT : 0;
	206	case UDF_RELOCATE_BLOCKS:
	207	{
	208	long old, new;
	209
	210	if (!capable(CAP_SYS_ADMIN)) return -EACCES;
	211	if (get_user(old, (long __user *)arg)) return -EFAULT;
	212	if ((result = udf_relocate_blocks(inode->i_sb,
	213	old, &new)) == 0)
	214	result = put_user(new, (long __user *)arg);
	215
	216	return result;
	217	}
	218	case UDF_GETEASIZE:
	219	result = put_user(UDF_I_LENEATTR(inode), (int __user *)arg);
	220	break;
	221
	222	case UDF_GETEABLOCK:
	223	result = copy_to_user((char __user *)arg, UDF_I_DATA(inode),
	224	UDF_I_LENEATTR(inode)) ? -EFAULT : 0;
	225	break;
	226	}
	227
	228	return result;
	229	}
	230
	231	/*
	232	* udf_release_file
	233	*
	234	* PURPOSE
	235	* Called when all references to the file are closed
	236	*
	237	* DESCRIPTION
	238	* Discard prealloced blocks
	239	*
	240	* HISTORY
	241	*
	242	*/
	243	static int udf_release_file(struct inode * inode, struct file * filp)
	244	{
	245	if (filp->f_mode & FMODE_WRITE)
	246	{
	247	lock_kernel();
	248	udf_discard_prealloc(inode);
	249	unlock_kernel();
	250	}
	251	return 0;
	252	}
253
4b6f5d20	254	const struct file_operations udf_file_operations = {
543ade1f BP	255	.read = do_sync_read,
543ade1f BP	256	.aio_read = generic_file_aio_read,
1da177e4 LT	257	.ioctl = udf_ioctl,
	258	.open = generic_file_open,
	259	.mmap = generic_file_mmap,
543ade1f BP	260	.write = do_sync_write,
543ade1f BP	261	.aio_write = udf_file_aio_write,
1da177e4 LT	262	.release = udf_release_file,
1da177e4 LT	263	.fsync = udf_fsync_file,
5ffc4ef4	264	.splice_read = generic_file_splice_read,
1da177e4 LT	265	};
1da177e4 LT	266
c5ef1c42	267	const struct inode_operations udf_file_inode_operations = {
1da177e4 LT	268	.truncate = udf_truncate,
1da177e4 LT	269	};