[deliverable/linux.git] / fs / udf / dir.c

/*
 * dir.c
 *
 * PURPOSE
 *  Directory 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) 1998-2004 Ben Fennema
 *
 * HISTORY
 *
 *  10/05/98 dgb  Split directory operations into its own file
 *                Implemented directory reads via do_udf_readdir
 *  10/06/98      Made directory operations work!
 *  11/17/98      Rewrote directory to support ICBTAG_FLAG_AD_LONG
 *  11/25/98 blf  Rewrote directory handling (readdir+lookup) to support reading
 *                across blocks.
 *  12/12/98      Split out the lookup code to namei.c. bulk of directory
 *                code now in directory.c:udf_fileident_read.
 */

#include "udfdecl.h"

#include <linux/string.h>
#include <linux/errno.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/smp_lock.h>
#include <linux/buffer_head.h>

#include "udf_i.h"
#include "udf_sb.h"

static int do_udf_readdir(struct inode *dir, struct file *filp,
			  filldir_t filldir, void *dirent)
{
	struct udf_fileident_bh fibh;
	struct fileIdentDesc *fi = NULL;
	struct fileIdentDesc cfi;
	int block, iblock;
	loff_t nf_pos = filp->f_pos - 1;
	int flen;
	char fname[UDF_NAME_LEN];
	char *nameptr;
	uint16_t liu;
	uint8_t lfi;
	loff_t size = (udf_ext0_offset(dir) + dir->i_size) >> 2;
	struct buffer_head *tmp, *bha[16];
	kernel_lb_addr eloc;
	uint32_t elen;
	sector_t offset;
	int i, num;
	unsigned int dt_type;
	struct extent_position epos = { NULL, 0, {0, 0} };
	struct udf_inode_info *iinfo;

	if (nf_pos >= size)
		return 0;

	if (nf_pos == 0)
		nf_pos = (udf_ext0_offset(dir) >> 2);

	fibh.soffset = fibh.eoffset = (nf_pos & ((dir->i_sb->s_blocksize - 1) >> 2)) << 2;
	iinfo = UDF_I(dir);
	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
		fibh.sbh = fibh.ebh = NULL;
	} else if (inode_bmap(dir, nf_pos >> (dir->i_sb->s_blocksize_bits - 2),
			      &epos, &eloc, &elen, &offset) == (EXT_RECORDED_ALLOCATED >> 30)) {
		block = udf_get_lb_pblock(dir->i_sb, eloc, offset);
		if ((++offset << dir->i_sb->s_blocksize_bits) < elen) {
			if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
				epos.offset -= sizeof(short_ad);
			else if (iinfo->i_alloc_type ==
					ICBTAG_FLAG_AD_LONG)
				epos.offset -= sizeof(long_ad);
		} else {
			offset = 0;
		}

		if (!(fibh.sbh = fibh.ebh = udf_tread(dir->i_sb, block))) {
			brelse(epos.bh);
			return -EIO;
		}

		if (!(offset & ((16 >> (dir->i_sb->s_blocksize_bits - 9)) - 1))) {
			i = 16 >> (dir->i_sb->s_blocksize_bits - 9);
			if (i + offset > (elen >> dir->i_sb->s_blocksize_bits))
				i = (elen >> dir->i_sb->s_blocksize_bits) - offset;
			for (num = 0; i > 0; i--) {
				block = udf_get_lb_pblock(dir->i_sb, eloc, offset + i);
				tmp = udf_tgetblk(dir->i_sb, block);
				if (tmp && !buffer_uptodate(tmp) && !buffer_locked(tmp))
					bha[num++] = tmp;
				else
					brelse(tmp);
			}
			if (num) {
				ll_rw_block(READA, num, bha);
				for (i = 0; i < num; i++)
					brelse(bha[i]);
			}
		}
	} else {
		brelse(epos.bh);
		return -ENOENT;
	}

	while (nf_pos < size) {
		filp->f_pos = nf_pos + 1;

		fi = udf_fileident_read(dir, &nf_pos, &fibh, &cfi, &epos, &eloc,
					&elen, &offset);
		if (!fi) {
			if (fibh.sbh != fibh.ebh)
				brelse(fibh.ebh);
			brelse(fibh.sbh);
			brelse(epos.bh);
			return 0;
		}

		liu = le16_to_cpu(cfi.lengthOfImpUse);
		lfi = cfi.lengthFileIdent;

		if (fibh.sbh == fibh.ebh) {
			nameptr = fi->fileIdent + liu;
		} else {
			int poffset;	/* Unpaded ending offset */

			poffset = fibh.soffset + sizeof(struct fileIdentDesc) + liu + lfi;

			if (poffset >= lfi) {
				nameptr = (char *)(fibh.ebh->b_data + poffset - lfi);
			} else {
				nameptr = fname;
				memcpy(nameptr, fi->fileIdent + liu,
				       lfi - poffset);
				memcpy(nameptr + lfi - poffset,
				       fibh.ebh->b_data, poffset);
			}
		}

		if ((cfi.fileCharacteristics & FID_FILE_CHAR_DELETED) != 0) {
			if (!UDF_QUERY_FLAG(dir->i_sb, UDF_FLAG_UNDELETE))
				continue;
		}

		if ((cfi.fileCharacteristics & FID_FILE_CHAR_HIDDEN) != 0) {
			if (!UDF_QUERY_FLAG(dir->i_sb, UDF_FLAG_UNHIDE))
				continue;
		}

		if (cfi.fileCharacteristics & FID_FILE_CHAR_PARENT) {
			iblock = parent_ino(filp->f_path.dentry);
			flen = 2;
			memcpy(fname, "..", flen);
			dt_type = DT_DIR;
		} else {
			kernel_lb_addr tloc = lelb_to_cpu(cfi.icb.extLocation);

			iblock = udf_get_lb_pblock(dir->i_sb, tloc, 0);
			flen = udf_get_filename(dir->i_sb, nameptr, fname, lfi);
			dt_type = DT_UNKNOWN;
		}

		if (flen) {
			if (filldir(dirent, fname, flen, filp->f_pos, iblock, dt_type) < 0) {
				if (fibh.sbh != fibh.ebh)
					brelse(fibh.ebh);
				brelse(fibh.sbh);
				brelse(epos.bh);
	 			return 0;
			}
		}
	} /* end while */

	filp->f_pos = nf_pos + 1;

	if (fibh.sbh != fibh.ebh)
		brelse(fibh.ebh);
	brelse(fibh.sbh);
	brelse(epos.bh);

	return 0;
}

/*
 * udf_readdir
 *
 * PURPOSE
 *	Read a directory entry.
 *
 * DESCRIPTION
 *	Optional - sys_getdents() will return -ENOTDIR if this routine is not
 *	available.
 *
 *	Refer to sys_getdents() in fs/readdir.c
 *	sys_getdents() -> .
 *
 * PRE-CONDITIONS
 *	filp			Pointer to directory file.
 *	buf			Pointer to directory entry buffer.
 *	filldir			Pointer to filldir function.
 *
 * POST-CONDITIONS
 *	<return>		>=0 on success.
 *
 * HISTORY
 *	July 1, 1997 - Andrew E. Mileski
 *	Written, tested, and released.
 */

static int udf_readdir(struct file *filp, void *dirent, filldir_t filldir)
{
	struct inode *dir = filp->f_path.dentry->d_inode;
	int result;

	lock_kernel();

	if (filp->f_pos == 0) {
		if (filldir(dirent, ".", 1, filp->f_pos, dir->i_ino, DT_DIR) < 0) {
			unlock_kernel();
			return 0;
		}
		filp->f_pos++;
	}

	result = do_udf_readdir(dir, filp, filldir, dirent);
	unlock_kernel();
 	return result;
}

/* readdir and lookup functions */
const struct file_operations udf_dir_operations = {
	.read			= generic_read_dir,
	.readdir		= udf_readdir,
	.ioctl			= udf_ioctl,
	.fsync			= udf_fsync_file,
};
Commit	Line	Data
1da177e4 LT	1	/*
	2	* dir.c
	3	*
	4	* PURPOSE
	5	* Directory 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) 1998-2004 Ben Fennema
	14	*
	15	* HISTORY
	16	*
	17	* 10/05/98 dgb Split directory operations into its own file
	18	* Implemented directory reads via do_udf_readdir
	19	* 10/06/98 Made directory operations work!
	20	* 11/17/98 Rewrote directory to support ICBTAG_FLAG_AD_LONG
	21	* 11/25/98 blf Rewrote directory handling (readdir+lookup) to support reading
	22	* across blocks.
	23	* 12/12/98 Split out the lookup code to namei.c. bulk of directory
	24	* code now in directory.c:udf_fileident_read.
	25	*/
	26
	27	#include "udfdecl.h"
	28
	29	#include <linux/string.h>
	30	#include <linux/errno.h>
	31	#include <linux/mm.h>
	32	#include <linux/slab.h>
	33	#include <linux/smp_lock.h>
	34	#include <linux/buffer_head.h>
	35
	36	#include "udf_i.h"
	37	#include "udf_sb.h"
	38
934c5e60 MS	39	static int do_udf_readdir(struct inode dir, struct file filp,
934c5e60 MS	40	filldir_t filldir, void *dirent)
1da177e4 LT	41	{
1da177e4 LT	42	struct udf_fileident_bh fibh;
cb00ea35	43	struct fileIdentDesc *fi = NULL;
1da177e4 LT	44	struct fileIdentDesc cfi;
	45	int block, iblock;
	46	loff_t nf_pos = filp->f_pos - 1;
	47	int flen;
	48	char fname[UDF_NAME_LEN];
	49	char *nameptr;
	50	uint16_t liu;
	51	uint8_t lfi;
	52	loff_t size = (udf_ext0_offset(dir) + dir->i_size) >> 2;
ff116fc8 JK	53	struct buffer_head tmp, bha[16];
	54	kernel_lb_addr eloc;
	55	uint32_t elen;
60448b1d	56	sector_t offset;
1da177e4 LT	57	int i, num;
1da177e4 LT	58	unsigned int dt_type;
cb00ea35	59	struct extent_position epos = { NULL, 0, {0, 0} };
48d6d8ff	60	struct udf_inode_info *iinfo;
1da177e4 LT	61
	62	if (nf_pos >= size)
	63	return 0;
	64
	65	if (nf_pos == 0)
	66	nf_pos = (udf_ext0_offset(dir) >> 2);
	67
28de7948	68	fibh.soffset = fibh.eoffset = (nf_pos & ((dir->i_sb->s_blocksize - 1) >> 2)) << 2;
48d6d8ff MS	69	iinfo = UDF_I(dir);
48d6d8ff MS	70	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
1da177e4	71	fibh.sbh = fibh.ebh = NULL;
28de7948 CG	72	} else if (inode_bmap(dir, nf_pos >> (dir->i_sb->s_blocksize_bits - 2),
28de7948 CG	73	&epos, &eloc, &elen, &offset) == (EXT_RECORDED_ALLOCATED >> 30)) {
1da177e4	74	block = udf_get_lb_pblock(dir->i_sb, eloc, offset);
cb00ea35	75	if ((++offset << dir->i_sb->s_blocksize_bits) < elen) {
48d6d8ff	76	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
ff116fc8	77	epos.offset -= sizeof(short_ad);
48d6d8ff	78	else if (iinfo->i_alloc_type ==
c0b34438	79	ICBTAG_FLAG_AD_LONG)
ff116fc8	80	epos.offset -= sizeof(long_ad);
28de7948	81	} else {
1da177e4	82	offset = 0;
28de7948	83	}
1da177e4	84
cb00ea35	85	if (!(fibh.sbh = fibh.ebh = udf_tread(dir->i_sb, block))) {
3bf25cb4	86	brelse(epos.bh);
1da177e4 LT	87	return -EIO;
1da177e4 LT	88	}
cb00ea35 CG	89
cb00ea35 CG	90	if (!(offset & ((16 >> (dir->i_sb->s_blocksize_bits - 9)) - 1))) {
1da177e4	91	i = 16 >> (dir->i_sb->s_blocksize_bits - 9);
cb00ea35	92	if (i + offset > (elen >> dir->i_sb->s_blocksize_bits))
28de7948	93	i = (elen >> dir->i_sb->s_blocksize_bits) - offset;
cb00ea35	94	for (num = 0; i > 0; i--) {
28de7948	95	block = udf_get_lb_pblock(dir->i_sb, eloc, offset + i);
1da177e4	96	tmp = udf_tgetblk(dir->i_sb, block);
28de7948	97	if (tmp && !buffer_uptodate(tmp) && !buffer_locked(tmp))
1da177e4 LT	98	bha[num++] = tmp;
	99	else
	100	brelse(tmp);
	101	}
cb00ea35	102	if (num) {
1da177e4	103	ll_rw_block(READA, num, bha);
cb00ea35	104	for (i = 0; i < num; i++)
1da177e4 LT	105	brelse(bha[i]);
	106	}
	107	}
cb00ea35	108	} else {
3bf25cb4	109	brelse(epos.bh);
1da177e4 LT	110	return -ENOENT;
	111	}
	112
cb00ea35	113	while (nf_pos < size) {
1da177e4 LT	114	filp->f_pos = nf_pos + 1;
1da177e4 LT	115
cb00ea35 CG	116	fi = udf_fileident_read(dir, &nf_pos, &fibh, &cfi, &epos, &eloc,
cb00ea35 CG	117	&elen, &offset);
cb00ea35	118	if (!fi) {
1da177e4	119	if (fibh.sbh != fibh.ebh)
3bf25cb4 JK	120	brelse(fibh.ebh);
	121	brelse(fibh.sbh);
	122	brelse(epos.bh);
1da177e4 LT	123	return 0;
	124	}
	125
	126	liu = le16_to_cpu(cfi.lengthOfImpUse);
	127	lfi = cfi.lengthFileIdent;
	128
28de7948	129	if (fibh.sbh == fibh.ebh) {
1da177e4	130	nameptr = fi->fileIdent + liu;
28de7948	131	} else {
1da177e4 LT	132	int poffset; /* Unpaded ending offset */
1da177e4 LT	133
28de7948	134	poffset = fibh.soffset + sizeof(struct fileIdentDesc) + liu + lfi;
1da177e4	135
28de7948 CG	136	if (poffset >= lfi) {
	137	nameptr = (char *)(fibh.ebh->b_data + poffset - lfi);
	138	} else {
1da177e4	139	nameptr = fname;
cb00ea35 CG	140	memcpy(nameptr, fi->fileIdent + liu,
	141	lfi - poffset);
	142	memcpy(nameptr + lfi - poffset,
	143	fibh.ebh->b_data, poffset);
1da177e4 LT	144	}
	145	}
	146
cb00ea35 CG	147	if ((cfi.fileCharacteristics & FID_FILE_CHAR_DELETED) != 0) {
cb00ea35 CG	148	if (!UDF_QUERY_FLAG(dir->i_sb, UDF_FLAG_UNDELETE))
1da177e4 LT	149	continue;
1da177e4 LT	150	}
cb00ea35 CG	151
	152	if ((cfi.fileCharacteristics & FID_FILE_CHAR_HIDDEN) != 0) {
	153	if (!UDF_QUERY_FLAG(dir->i_sb, UDF_FLAG_UNHIDE))
1da177e4 LT	154	continue;
	155	}
	156
cb00ea35	157	if (cfi.fileCharacteristics & FID_FILE_CHAR_PARENT) {
5096e933	158	iblock = parent_ino(filp->f_path.dentry);
1da177e4 LT	159	flen = 2;
	160	memcpy(fname, "..", flen);
	161	dt_type = DT_DIR;
cb00ea35	162	} else {
1da177e4 LT	163	kernel_lb_addr tloc = lelb_to_cpu(cfi.icb.extLocation);
	164
	165	iblock = udf_get_lb_pblock(dir->i_sb, tloc, 0);
	166	flen = udf_get_filename(dir->i_sb, nameptr, fname, lfi);
	167	dt_type = DT_UNKNOWN;
	168	}
	169
cb00ea35	170	if (flen) {
28de7948	171	if (filldir(dirent, fname, flen, filp->f_pos, iblock, dt_type) < 0) {
1da177e4	172	if (fibh.sbh != fibh.ebh)
3bf25cb4 JK	173	brelse(fibh.ebh);
	174	brelse(fibh.sbh);
	175	brelse(epos.bh);
28de7948	176	return 0;
1da177e4 LT	177	}
1da177e4 LT	178	}
28de7948	179	} /* end while */
1da177e4 LT	180
	181	filp->f_pos = nf_pos + 1;
	182
	183	if (fibh.sbh != fibh.ebh)
3bf25cb4 JK	184	brelse(fibh.ebh);
	185	brelse(fibh.sbh);
	186	brelse(epos.bh);
1da177e4 LT	187
	188	return 0;
	189	}
934c5e60 MS	190
	191	/*
	192	* udf_readdir
	193	*
	194	* PURPOSE
	195	* Read a directory entry.
	196	*
	197	* DESCRIPTION
	198	* Optional - sys_getdents() will return -ENOTDIR if this routine is not
	199	* available.
	200	*
	201	* Refer to sys_getdents() in fs/readdir.c
	202	* sys_getdents() -> .
	203	*
	204	* PRE-CONDITIONS
	205	* filp Pointer to directory file.
	206	* buf Pointer to directory entry buffer.
	207	* filldir Pointer to filldir function.
	208	*
	209	* POST-CONDITIONS
	210	* <return> >=0 on success.
	211	*
	212	* HISTORY
	213	* July 1, 1997 - Andrew E. Mileski
	214	* Written, tested, and released.
	215	*/
	216
	217	static int udf_readdir(struct file filp, void dirent, filldir_t filldir)
	218	{
	219	struct inode *dir = filp->f_path.dentry->d_inode;
	220	int result;
	221
	222	lock_kernel();
	223
	224	if (filp->f_pos == 0) {
	225	if (filldir(dirent, ".", 1, filp->f_pos, dir->i_ino, DT_DIR) < 0) {
	226	unlock_kernel();
	227	return 0;
	228	}
	229	filp->f_pos++;
	230	}
	231
	232	result = do_udf_readdir(dir, filp, filldir, dirent);
	233	unlock_kernel();
	234	return result;
	235	}
	236
	237	/* readdir and lookup functions */
	238	const struct file_operations udf_dir_operations = {
	239	.read = generic_read_dir,
	240	.readdir = udf_readdir,
	241	.ioctl = udf_ioctl,
	242	.fsync = udf_fsync_file,
	243	};