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v4.10.11
  1/*
  2 * dir.c
  3 *
  4 * PURPOSE
  5 *  Directory handling routines for the OSTA-UDF(tm) filesystem.
  6 *
  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/bio.h>
 34
 35#include "udf_i.h"
 36#include "udf_sb.h"
 37
 38
 39static int udf_readdir(struct file *file, struct dir_context *ctx)
 40{
 41	struct inode *dir = file_inode(file);
 42	struct udf_inode_info *iinfo = UDF_I(dir);
 43	struct udf_fileident_bh fibh = { .sbh = NULL, .ebh = NULL};
 44	struct fileIdentDesc *fi = NULL;
 45	struct fileIdentDesc cfi;
 46	int block, iblock;
 47	loff_t nf_pos;
 48	int flen;
 49	unsigned char *fname = NULL, *copy_name = NULL;
 50	unsigned char *nameptr;
 51	uint16_t liu;
 52	uint8_t lfi;
 53	loff_t size = udf_ext0_offset(dir) + dir->i_size;
 54	struct buffer_head *tmp, *bha[16];
 55	struct kernel_lb_addr eloc;
 56	uint32_t elen;
 57	sector_t offset;
 58	int i, num, ret = 0;
 59	struct extent_position epos = { NULL, 0, {0, 0} };
 60	struct super_block *sb = dir->i_sb;
 61
 62	if (ctx->pos == 0) {
 63		if (!dir_emit_dot(file, ctx))
 64			return 0;
 65		ctx->pos = 1;
 66	}
 67	nf_pos = (ctx->pos - 1) << 2;
 68	if (nf_pos >= size)
 69		goto out;
 70
 71	fname = kmalloc(UDF_NAME_LEN, GFP_NOFS);
 72	if (!fname) {
 73		ret = -ENOMEM;
 74		goto out;
 75	}
 76
 77	if (nf_pos == 0)
 78		nf_pos = udf_ext0_offset(dir);
 79
 80	fibh.soffset = fibh.eoffset = nf_pos & (sb->s_blocksize - 1);
 81	if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
 82		if (inode_bmap(dir, nf_pos >> sb->s_blocksize_bits,
 83		    &epos, &eloc, &elen, &offset)
 84		    != (EXT_RECORDED_ALLOCATED >> 30)) {
 85			ret = -ENOENT;
 86			goto out;
 87		}
 88		block = udf_get_lb_pblock(sb, &eloc, offset);
 89		if ((++offset << sb->s_blocksize_bits) < elen) {
 90			if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
 91				epos.offset -= sizeof(struct short_ad);
 92			else if (iinfo->i_alloc_type ==
 93					ICBTAG_FLAG_AD_LONG)
 94				epos.offset -= sizeof(struct long_ad);
 95		} else {
 96			offset = 0;
 97		}
 98
 99		if (!(fibh.sbh = fibh.ebh = udf_tread(sb, block))) {
100			ret = -EIO;
101			goto out;
102		}
103
104		if (!(offset & ((16 >> (sb->s_blocksize_bits - 9)) - 1))) {
105			i = 16 >> (sb->s_blocksize_bits - 9);
106			if (i + offset > (elen >> sb->s_blocksize_bits))
107				i = (elen >> sb->s_blocksize_bits) - offset;
108			for (num = 0; i > 0; i--) {
109				block = udf_get_lb_pblock(sb, &eloc, offset + i);
110				tmp = udf_tgetblk(sb, block);
111				if (tmp && !buffer_uptodate(tmp) && !buffer_locked(tmp))
112					bha[num++] = tmp;
113				else
114					brelse(tmp);
115			}
116			if (num) {
117				ll_rw_block(REQ_OP_READ, REQ_RAHEAD, num, bha);
118				for (i = 0; i < num; i++)
119					brelse(bha[i]);
120			}
121		}
122	}
123
124	while (nf_pos < size) {
125		struct kernel_lb_addr tloc;
126
127		ctx->pos = (nf_pos >> 2) + 1;
128
129		fi = udf_fileident_read(dir, &nf_pos, &fibh, &cfi, &epos, &eloc,
130					&elen, &offset);
131		if (!fi)
132			goto out;
133
134		liu = le16_to_cpu(cfi.lengthOfImpUse);
135		lfi = cfi.lengthFileIdent;
136
137		if (fibh.sbh == fibh.ebh) {
138			nameptr = fi->fileIdent + liu;
139		} else {
140			int poffset;	/* Unpaded ending offset */
141
142			poffset = fibh.soffset + sizeof(struct fileIdentDesc) + liu + lfi;
143
144			if (poffset >= lfi) {
145				nameptr = (char *)(fibh.ebh->b_data + poffset - lfi);
146			} else {
147				if (!copy_name) {
148					copy_name = kmalloc(UDF_NAME_LEN,
149							    GFP_NOFS);
150					if (!copy_name) {
151						ret = -ENOMEM;
152						goto out;
153					}
154				}
155				nameptr = copy_name;
156				memcpy(nameptr, fi->fileIdent + liu,
157				       lfi - poffset);
158				memcpy(nameptr + lfi - poffset,
159				       fibh.ebh->b_data, poffset);
160			}
161		}
162
163		if ((cfi.fileCharacteristics & FID_FILE_CHAR_DELETED) != 0) {
164			if (!UDF_QUERY_FLAG(sb, UDF_FLAG_UNDELETE))
165				continue;
166		}
167
168		if ((cfi.fileCharacteristics & FID_FILE_CHAR_HIDDEN) != 0) {
169			if (!UDF_QUERY_FLAG(sb, UDF_FLAG_UNHIDE))
170				continue;
171		}
172
173		if (cfi.fileCharacteristics & FID_FILE_CHAR_PARENT) {
174			if (!dir_emit_dotdot(file, ctx))
175				goto out;
176			continue;
177		}
178
179		flen = udf_get_filename(sb, nameptr, lfi, fname, UDF_NAME_LEN);
180		if (flen < 0)
181			continue;
182
183		tloc = lelb_to_cpu(cfi.icb.extLocation);
184		iblock = udf_get_lb_pblock(sb, &tloc, 0);
185		if (!dir_emit(ctx, fname, flen, iblock, DT_UNKNOWN))
186			goto out;
187	} /* end while */
188
189	ctx->pos = (nf_pos >> 2) + 1;
190
191out:
192	if (fibh.sbh != fibh.ebh)
193		brelse(fibh.ebh);
194	brelse(fibh.sbh);
195	brelse(epos.bh);
196	kfree(fname);
197	kfree(copy_name);
198
199	return ret;
200}
201
202/* readdir and lookup functions */
203const struct file_operations udf_dir_operations = {
204	.llseek			= generic_file_llseek,
205	.read			= generic_read_dir,
206	.iterate_shared		= udf_readdir,
207	.unlocked_ioctl		= udf_ioctl,
208	.fsync			= generic_file_fsync,
209};
v5.4
  1/*
  2 * dir.c
  3 *
  4 * PURPOSE
  5 *  Directory handling routines for the OSTA-UDF(tm) filesystem.
  6 *
  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/bio.h>
 34
 35#include "udf_i.h"
 36#include "udf_sb.h"
 37
 38
 39static int udf_readdir(struct file *file, struct dir_context *ctx)
 40{
 41	struct inode *dir = file_inode(file);
 42	struct udf_inode_info *iinfo = UDF_I(dir);
 43	struct udf_fileident_bh fibh = { .sbh = NULL, .ebh = NULL};
 44	struct fileIdentDesc *fi = NULL;
 45	struct fileIdentDesc cfi;
 46	udf_pblk_t block, iblock;
 47	loff_t nf_pos;
 48	int flen;
 49	unsigned char *fname = NULL, *copy_name = NULL;
 50	unsigned char *nameptr;
 51	uint16_t liu;
 52	uint8_t lfi;
 53	loff_t size = udf_ext0_offset(dir) + dir->i_size;
 54	struct buffer_head *tmp, *bha[16];
 55	struct kernel_lb_addr eloc;
 56	uint32_t elen;
 57	sector_t offset;
 58	int i, num, ret = 0;
 59	struct extent_position epos = { NULL, 0, {0, 0} };
 60	struct super_block *sb = dir->i_sb;
 61
 62	if (ctx->pos == 0) {
 63		if (!dir_emit_dot(file, ctx))
 64			return 0;
 65		ctx->pos = 1;
 66	}
 67	nf_pos = (ctx->pos - 1) << 2;
 68	if (nf_pos >= size)
 69		goto out;
 70
 71	fname = kmalloc(UDF_NAME_LEN, GFP_NOFS);
 72	if (!fname) {
 73		ret = -ENOMEM;
 74		goto out;
 75	}
 76
 77	if (nf_pos == 0)
 78		nf_pos = udf_ext0_offset(dir);
 79
 80	fibh.soffset = fibh.eoffset = nf_pos & (sb->s_blocksize - 1);
 81	if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
 82		if (inode_bmap(dir, nf_pos >> sb->s_blocksize_bits,
 83		    &epos, &eloc, &elen, &offset)
 84		    != (EXT_RECORDED_ALLOCATED >> 30)) {
 85			ret = -ENOENT;
 86			goto out;
 87		}
 88		block = udf_get_lb_pblock(sb, &eloc, offset);
 89		if ((++offset << sb->s_blocksize_bits) < elen) {
 90			if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
 91				epos.offset -= sizeof(struct short_ad);
 92			else if (iinfo->i_alloc_type ==
 93					ICBTAG_FLAG_AD_LONG)
 94				epos.offset -= sizeof(struct long_ad);
 95		} else {
 96			offset = 0;
 97		}
 98
 99		if (!(fibh.sbh = fibh.ebh = udf_tread(sb, block))) {
100			ret = -EIO;
101			goto out;
102		}
103
104		if (!(offset & ((16 >> (sb->s_blocksize_bits - 9)) - 1))) {
105			i = 16 >> (sb->s_blocksize_bits - 9);
106			if (i + offset > (elen >> sb->s_blocksize_bits))
107				i = (elen >> sb->s_blocksize_bits) - offset;
108			for (num = 0; i > 0; i--) {
109				block = udf_get_lb_pblock(sb, &eloc, offset + i);
110				tmp = udf_tgetblk(sb, block);
111				if (tmp && !buffer_uptodate(tmp) && !buffer_locked(tmp))
112					bha[num++] = tmp;
113				else
114					brelse(tmp);
115			}
116			if (num) {
117				ll_rw_block(REQ_OP_READ, REQ_RAHEAD, num, bha);
118				for (i = 0; i < num; i++)
119					brelse(bha[i]);
120			}
121		}
122	}
123
124	while (nf_pos < size) {
125		struct kernel_lb_addr tloc;
126
127		ctx->pos = (nf_pos >> 2) + 1;
128
129		fi = udf_fileident_read(dir, &nf_pos, &fibh, &cfi, &epos, &eloc,
130					&elen, &offset);
131		if (!fi)
132			goto out;
133
134		liu = le16_to_cpu(cfi.lengthOfImpUse);
135		lfi = cfi.lengthFileIdent;
136
137		if (fibh.sbh == fibh.ebh) {
138			nameptr = fi->fileIdent + liu;
139		} else {
140			int poffset;	/* Unpaded ending offset */
141
142			poffset = fibh.soffset + sizeof(struct fileIdentDesc) + liu + lfi;
143
144			if (poffset >= lfi) {
145				nameptr = (char *)(fibh.ebh->b_data + poffset - lfi);
146			} else {
147				if (!copy_name) {
148					copy_name = kmalloc(UDF_NAME_LEN,
149							    GFP_NOFS);
150					if (!copy_name) {
151						ret = -ENOMEM;
152						goto out;
153					}
154				}
155				nameptr = copy_name;
156				memcpy(nameptr, fi->fileIdent + liu,
157				       lfi - poffset);
158				memcpy(nameptr + lfi - poffset,
159				       fibh.ebh->b_data, poffset);
160			}
161		}
162
163		if ((cfi.fileCharacteristics & FID_FILE_CHAR_DELETED) != 0) {
164			if (!UDF_QUERY_FLAG(sb, UDF_FLAG_UNDELETE))
165				continue;
166		}
167
168		if ((cfi.fileCharacteristics & FID_FILE_CHAR_HIDDEN) != 0) {
169			if (!UDF_QUERY_FLAG(sb, UDF_FLAG_UNHIDE))
170				continue;
171		}
172
173		if (cfi.fileCharacteristics & FID_FILE_CHAR_PARENT) {
174			if (!dir_emit_dotdot(file, ctx))
175				goto out;
176			continue;
177		}
178
179		flen = udf_get_filename(sb, nameptr, lfi, fname, UDF_NAME_LEN);
180		if (flen < 0)
181			continue;
182
183		tloc = lelb_to_cpu(cfi.icb.extLocation);
184		iblock = udf_get_lb_pblock(sb, &tloc, 0);
185		if (!dir_emit(ctx, fname, flen, iblock, DT_UNKNOWN))
186			goto out;
187	} /* end while */
188
189	ctx->pos = (nf_pos >> 2) + 1;
190
191out:
192	if (fibh.sbh != fibh.ebh)
193		brelse(fibh.ebh);
194	brelse(fibh.sbh);
195	brelse(epos.bh);
196	kfree(fname);
197	kfree(copy_name);
198
199	return ret;
200}
201
202/* readdir and lookup functions */
203const struct file_operations udf_dir_operations = {
204	.llseek			= generic_file_llseek,
205	.read			= generic_read_dir,
206	.iterate_shared		= udf_readdir,
207	.unlocked_ioctl		= udf_ioctl,
208	.fsync			= generic_file_fsync,
209};