/* * 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/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 = { .sbh = NULL, .ebh = NULL};	struct fileIdentDesc *fi = NULL;	struct fileIdentDesc cfi;	int block, iblock;	loff_t nf_pos = (filp->f_pos - 1) << 2;	int flen;	unsigned char *fname = NULL;	unsigned char *nameptr;	uint16_t liu;	uint8_t lfi;	loff_t size = udf_ext0_offset(dir) + dir->i_size;	struct buffer_head *tmp, *bha[16];	struct kernel_lb_addr eloc;	uint32_t elen;	sector_t offset;	int i, num, ret = 0;	unsigned int dt_type;	struct extent_position epos = { NULL, 0, {0, 0} };	struct udf_inode_info *iinfo; 	if (nf_pos >= size)		goto out; 	fname = kmalloc(UDF_NAME_LEN, GFP_NOFS);	if (!fname) {		ret = -ENOMEM;		goto out;	} 	if (nf_pos == 0)		nf_pos = udf_ext0_offset(dir); 	fibh.soffset = fibh.eoffset = nf_pos & (dir->i_sb->s_blocksize - 1);	iinfo = UDF_I(dir);	if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {		if (inode_bmap(dir, nf_pos >> dir->i_sb->s_blocksize_bits,		    &epos, &eloc, &elen, &offset)		    != (EXT_RECORDED_ALLOCATED >> 30)) {			ret = -ENOENT;			goto out;		}		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(struct short_ad);			else if (iinfo->i_alloc_type ==					ICBTAG_FLAG_AD_LONG)				epos.offset -= sizeof(struct long_ad);		} else {			offset = 0;		} 		if (!(fibh.sbh = fibh.ebh = udf_tread(dir->i_sb, block))) {			ret = -EIO;			goto out;		} 		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]);			}		}	} 	while (nf_pos < size) {		filp->f_pos = (nf_pos >> 2) + 1; 		fi = udf_fileident_read(dir, &nf_pos, &fibh, &cfi, &epos, &eloc,					&elen, &offset);		if (!fi)			goto out; 		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 {			struct 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 && filldir(dirent, fname, flen, filp->f_pos,				    iblock, dt_type) < 0)			goto out;	} /* end while */ 	filp->f_pos = (nf_pos >> 2) + 1; out:	if (fibh.sbh != fibh.ebh)		brelse(fibh.ebh);	brelse(fibh.sbh);	brelse(epos.bh);	kfree(fname); 	return ret;} static int udf_readdir(struct file *filp, void *dirent, filldir_t filldir){	struct inode *dir = filp->f_path.dentry->d_inode;	int result; 	if (filp->f_pos == 0) {		if (filldir(dirent, ".", 1, filp->f_pos, dir->i_ino, DT_DIR) < 0) {			return 0;		}		filp->f_pos++;	} 	result = do_udf_readdir(dir, filp, filldir, dirent); 	return result;} /* readdir and lookup functions */const struct file_operations udf_dir_operations = {	.llseek			= generic_file_llseek,	.read			= generic_read_dir,	.readdir		= udf_readdir,	.unlocked_ioctl		= udf_ioctl,	.fsync			= generic_file_fsync,};