5 * Truncate handling routines for the OSTA-UDF(tm) filesystem.
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.
13 * (C) 1999-2004 Ben Fennema
14 * (C) 1999 Stelias Computing Inc
18 * 02/24/99 blf Created.
25 #include <linux/udf_fs.h>
26 #include <linux/buffer_head.h>
31 static void extent_trunc(struct inode *inode, struct extent_position *epos,
32 kernel_lb_addr eloc, int8_t etype, uint32_t elen,
35 kernel_lb_addr neloc = {};
36 int last_block = (elen + inode->i_sb->s_blocksize - 1) >>
37 inode->i_sb->s_blocksize_bits;
38 int first_block = (nelen + inode->i_sb->s_blocksize - 1) >>
39 inode->i_sb->s_blocksize_bits;
42 if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) {
43 udf_free_blocks(inode->i_sb, inode, eloc, 0,
45 etype = (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30);
48 nelen = (etype << 30) | nelen;
52 udf_write_aext(inode, epos, neloc, nelen, 0);
53 if (last_block - first_block > 0) {
54 if (etype == (EXT_RECORDED_ALLOCATED >> 30))
55 mark_inode_dirty(inode);
57 if (etype != (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
58 udf_free_blocks(inode->i_sb, inode, eloc,
60 last_block - first_block);
66 * Truncate the last extent to match i_size. This function assumes
67 * that preallocation extent is already truncated.
69 void udf_truncate_tail_extent(struct inode *inode)
71 struct extent_position epos = {};
75 int8_t etype = -1, netype;
78 if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_IN_ICB ||
79 inode->i_size == UDF_I_LENEXTENTS(inode))
81 /* Are we going to delete the file anyway? */
82 if (inode->i_nlink == 0)
85 if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_SHORT)
86 adsize = sizeof(short_ad);
87 else if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_LONG)
88 adsize = sizeof(long_ad);
92 /* Find the last extent in the file */
93 while ((netype = udf_next_aext(inode, &epos, &eloc, &elen, 1)) != -1) {
96 if (lbcount > inode->i_size) {
97 if (lbcount - inode->i_size >= inode->i_sb->s_blocksize)
99 "udf_truncate_tail_extent(): Too long "
100 "extent after EOF in inode %u: i_size: "
101 "%Ld lbcount: %Ld extent %u+%u\n",
102 (unsigned)inode->i_ino,
103 (long long)inode->i_size,
105 (unsigned)eloc.logicalBlockNum,
107 nelen = elen - (lbcount - inode->i_size);
108 epos.offset -= adsize;
109 extent_trunc(inode, &epos, eloc, etype, elen, nelen);
110 epos.offset += adsize;
111 if (udf_next_aext(inode, &epos, &eloc, &elen, 1) != -1)
112 printk(KERN_ERR "udf_truncate_tail_extent(): "
113 "Extent after EOF in inode %u.\n",
114 (unsigned)inode->i_ino);
118 /* This inode entry is in-memory only and thus we don't have to mark
120 UDF_I_LENEXTENTS(inode) = inode->i_size;
124 void udf_discard_prealloc(struct inode *inode)
126 struct extent_position epos = { NULL, 0, {0, 0} };
129 uint64_t lbcount = 0;
130 int8_t etype = -1, netype;
133 if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_IN_ICB ||
134 inode->i_size == UDF_I_LENEXTENTS(inode))
137 if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_SHORT)
138 adsize = sizeof(short_ad);
139 else if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_LONG)
140 adsize = sizeof(long_ad);
144 epos.block = UDF_I_LOCATION(inode);
146 /* Find the last extent in the file */
147 while ((netype = udf_next_aext(inode, &epos, &eloc, &elen, 1)) != -1) {
151 if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) {
152 epos.offset -= adsize;
154 extent_trunc(inode, &epos, eloc, etype, elen, 0);
156 UDF_I_LENALLOC(inode) =
158 udf_file_entry_alloc_offset(inode);
159 mark_inode_dirty(inode);
161 struct allocExtDesc *aed =
162 (struct allocExtDesc *)(epos.bh->b_data);
163 aed->lengthAllocDescs =
164 cpu_to_le32(epos.offset -
165 sizeof(struct allocExtDesc));
166 if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
167 UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
168 udf_update_tag(epos.bh->b_data, epos.offset);
170 udf_update_tag(epos.bh->b_data,
171 sizeof(struct allocExtDesc));
172 mark_buffer_dirty_inode(epos.bh, inode);
175 /* This inode entry is in-memory only and thus we don't have to mark
177 UDF_I_LENEXTENTS(inode) = lbcount;
181 void udf_truncate_extents(struct inode *inode)
183 struct extent_position epos;
184 kernel_lb_addr eloc, neloc = {};
185 uint32_t elen, nelen = 0, indirect_ext_len = 0, lenalloc;
187 struct super_block *sb = inode->i_sb;
188 struct udf_sb_info *sbi = UDF_SB(sb);
189 sector_t first_block = inode->i_size >> sb->s_blocksize_bits, offset;
193 if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_SHORT)
194 adsize = sizeof(short_ad);
195 else if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_LONG)
196 adsize = sizeof(long_ad);
200 etype = inode_bmap(inode, first_block, &epos, &eloc, &elen, &offset);
201 byte_offset = (offset << sb->s_blocksize_bits) +
202 (inode->i_size & (sb->s_blocksize - 1));
204 epos.offset -= adsize;
205 extent_trunc(inode, &epos, eloc, etype, elen, byte_offset);
206 epos.offset += adsize;
208 lenalloc = epos.offset;
210 lenalloc = epos.offset - adsize;
213 lenalloc -= udf_file_entry_alloc_offset(inode);
215 lenalloc -= sizeof(struct allocExtDesc);
217 while ((etype = udf_current_aext(inode, &epos, &eloc,
219 if (etype == (EXT_NEXT_EXTENT_ALLOCDECS >> 30)) {
220 udf_write_aext(inode, &epos, neloc, nelen, 0);
221 if (indirect_ext_len) {
222 /* We managed to free all extents in the
223 * indirect extent - free it too */
226 udf_free_blocks(sb, inode, epos.block,
227 0, indirect_ext_len);
230 UDF_I_LENALLOC(inode) =
232 mark_inode_dirty(inode);
234 struct allocExtDesc *aed =
235 (struct allocExtDesc *)
238 sizeof(struct allocExtDesc);
240 aed->lengthAllocDescs =
241 cpu_to_le32(lenalloc);
242 if (!UDF_QUERY_FLAG(sb,
244 sbi->s_udfrev >= 0x0201)
247 udf_update_tag(epos.bh->b_data,
249 mark_buffer_dirty_inode(
254 epos.offset = sizeof(struct allocExtDesc);
256 epos.bh = udf_tread(sb,
257 udf_get_lb_pblock(sb, eloc, 0));
260 (elen + sb->s_blocksize - 1) >>
261 sb->s_blocksize_bits;
263 indirect_ext_len = 1;
265 extent_trunc(inode, &epos, eloc, etype,
267 epos.offset += adsize;
271 if (indirect_ext_len) {
274 udf_free_blocks(sb, inode, epos.block, 0,
278 UDF_I_LENALLOC(inode) = lenalloc;
279 mark_inode_dirty(inode);
281 struct allocExtDesc *aed =
282 (struct allocExtDesc *)(epos.bh->b_data);
283 aed->lengthAllocDescs = cpu_to_le32(lenalloc);
284 if (!UDF_QUERY_FLAG(sb, UDF_FLAG_STRICT) ||
285 sbi->s_udfrev >= 0x0201)
286 udf_update_tag(epos.bh->b_data,
288 sizeof(struct allocExtDesc));
290 udf_update_tag(epos.bh->b_data,
291 sizeof(struct allocExtDesc));
292 mark_buffer_dirty_inode(epos.bh, inode);
295 } else if (inode->i_size) {
297 kernel_long_ad extent;
300 * OK, there is not extent covering inode->i_size and
301 * no extent above inode->i_size => truncate is
302 * extending the file by 'offset' blocks.
306 udf_file_entry_alloc_offset(inode)) ||
307 (epos.bh && epos.offset ==
308 sizeof(struct allocExtDesc))) {
309 /* File has no extents at all or has empty last
310 * indirect extent! Create a fake extent... */
311 extent.extLocation.logicalBlockNum = 0;
312 extent.extLocation.partitionReferenceNum = 0;
314 EXT_NOT_RECORDED_NOT_ALLOCATED;
316 epos.offset -= adsize;
317 etype = udf_next_aext(inode, &epos,
319 &extent.extLength, 0);
320 extent.extLength |= etype << 30;
322 udf_extend_file(inode, &epos, &extent,
325 (sb->s_blocksize - 1)) != 0));
328 UDF_I_LENEXTENTS(inode) = inode->i_size;