/* * 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" /* Prototypes for file operations */static int udf_readdir(struct file *, void *, filldir_t);static int do_udf_readdir(struct inode *, struct file *, filldir_t, void *); /* 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,}; /* * 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. */ int udf_readdir(struct file *filp, void *dirent, filldir_t filldir){	struct inode *dir = filp->f_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;} 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 * bh = NULL, * tmp, * bha[16];	kernel_lb_addr bloc, eloc;	uint32_t extoffset, elen, offset;	int i, num;	unsigned int dt_type; 	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;	if (UDF_I_ALLOCTYPE(dir) == ICBTAG_FLAG_AD_IN_ICB)		fibh.sbh = fibh.ebh = NULL;	else if (inode_bmap(dir, nf_pos >> (dir->i_sb->s_blocksize_bits - 2),		&bloc, &extoffset, &eloc, &elen, &offset, &bh) == (EXT_RECORDED_ALLOCATED >> 30))	{		offset >>= dir->i_sb->s_blocksize_bits;		block = udf_get_lb_pblock(dir->i_sb, eloc, offset);		if ((++offset << dir->i_sb->s_blocksize_bits) < elen)		{			if (UDF_I_ALLOCTYPE(dir) == ICBTAG_FLAG_AD_SHORT)				extoffset -= sizeof(short_ad);			else if (UDF_I_ALLOCTYPE(dir) == ICBTAG_FLAG_AD_LONG)				extoffset -= sizeof(long_ad);		}		else			offset = 0; 		if (!(fibh.sbh = fibh.ebh = udf_tread(dir->i_sb, block)))		{			udf_release_data(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	{		udf_release_data(bh);		return -ENOENT;	} 	while ( nf_pos < size )	{		filp->f_pos = nf_pos + 1; 		fi = udf_fileident_read(dir, &nf_pos, &fibh, &cfi, &bloc, &extoffset, &eloc, &elen, &offset, &bh); 		if (!fi)		{			if (fibh.sbh != fibh.ebh)				udf_release_data(fibh.ebh);			udf_release_data(fibh.sbh);			udf_release_data(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_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)					udf_release_data(fibh.ebh);				udf_release_data(fibh.sbh);				udf_release_data(bh);	 			return 0;			}		}	} /* end while */ 	filp->f_pos = nf_pos + 1; 	if (fibh.sbh != fibh.ebh)		udf_release_data(fibh.ebh);	udf_release_data(fibh.sbh);	udf_release_data(bh); 	return 0;}