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/buffer_head.h>
30 static void extent_trunc(struct inode *inode, struct extent_position *epos,
31 kernel_lb_addr eloc, int8_t etype, uint32_t elen,
34 kernel_lb_addr neloc = {};
35 int last_block = (elen + inode->i_sb->s_blocksize - 1) >>
36 inode->i_sb->s_blocksize_bits;
37 int first_block = (nelen + inode->i_sb->s_blocksize - 1) >>
38 inode->i_sb->s_blocksize_bits;
41 if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) {
42 udf_free_blocks(inode->i_sb, inode, eloc, 0,
44 etype = (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30);
47 nelen = (etype << 30) | nelen;
51 udf_write_aext(inode, epos, neloc, nelen, 0);
52 if (last_block - first_block > 0) {
53 if (etype == (EXT_RECORDED_ALLOCATED >> 30))
54 mark_inode_dirty(inode);
56 if (etype != (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
57 udf_free_blocks(inode->i_sb, inode, eloc,
59 last_block - first_block);
65 * Truncate the last extent to match i_size. This function assumes
66 * that preallocation extent is already truncated.
68 void udf_truncate_tail_extent(struct inode *inode)
70 struct extent_position epos = {};
74 int8_t etype = -1, netype;
76 struct udf_inode_info *iinfo = UDF_I(inode);
78 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB ||
79 inode->i_size == iinfo->i_lenExtents)
81 /* Are we going to delete the file anyway? */
82 if (inode->i_nlink == 0)
85 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
86 adsize = sizeof(short_ad);
87 else if (iinfo->i_alloc_type == 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 iinfo->i_lenExtents = 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;
132 struct udf_inode_info *iinfo = UDF_I(inode);
134 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB ||
135 inode->i_size == iinfo->i_lenExtents)
138 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
139 adsize = sizeof(short_ad);
140 else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
141 adsize = sizeof(long_ad);
145 epos.block = iinfo->i_location;
147 /* Find the last extent in the file */
148 while ((netype = udf_next_aext(inode, &epos, &eloc, &elen, 1)) != -1) {
152 if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) {
153 epos.offset -= adsize;
155 extent_trunc(inode, &epos, eloc, etype, elen, 0);
159 udf_file_entry_alloc_offset(inode);
160 mark_inode_dirty(inode);
162 struct allocExtDesc *aed =
163 (struct allocExtDesc *)(epos.bh->b_data);
164 aed->lengthAllocDescs =
165 cpu_to_le32(epos.offset -
166 sizeof(struct allocExtDesc));
167 if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) ||
168 UDF_SB(inode->i_sb)->s_udfrev >= 0x0201)
169 udf_update_tag(epos.bh->b_data, epos.offset);
171 udf_update_tag(epos.bh->b_data,
172 sizeof(struct allocExtDesc));
173 mark_buffer_dirty_inode(epos.bh, inode);
176 /* This inode entry is in-memory only and thus we don't have to mark
178 iinfo->i_lenExtents = lbcount;
182 void udf_truncate_extents(struct inode *inode)
184 struct extent_position epos;
185 kernel_lb_addr eloc, neloc = {};
186 uint32_t elen, nelen = 0, indirect_ext_len = 0, lenalloc;
188 struct super_block *sb = inode->i_sb;
189 struct udf_sb_info *sbi = UDF_SB(sb);
190 sector_t first_block = inode->i_size >> sb->s_blocksize_bits, offset;
193 struct udf_inode_info *iinfo = UDF_I(inode);
195 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
196 adsize = sizeof(short_ad);
197 else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
198 adsize = sizeof(long_ad);
202 etype = inode_bmap(inode, first_block, &epos, &eloc, &elen, &offset);
203 byte_offset = (offset << sb->s_blocksize_bits) +
204 (inode->i_size & (sb->s_blocksize - 1));
206 epos.offset -= adsize;
207 extent_trunc(inode, &epos, eloc, etype, elen, byte_offset);
208 epos.offset += adsize;
210 lenalloc = epos.offset;
212 lenalloc = epos.offset - adsize;
215 lenalloc -= udf_file_entry_alloc_offset(inode);
217 lenalloc -= sizeof(struct allocExtDesc);
219 while ((etype = udf_current_aext(inode, &epos, &eloc,
221 if (etype == (EXT_NEXT_EXTENT_ALLOCDECS >> 30)) {
222 udf_write_aext(inode, &epos, neloc, nelen, 0);
223 if (indirect_ext_len) {
224 /* We managed to free all extents in the
225 * indirect extent - free it too */
228 udf_free_blocks(sb, inode, epos.block,
229 0, indirect_ext_len);
234 mark_inode_dirty(inode);
236 struct allocExtDesc *aed =
237 (struct allocExtDesc *)
240 sizeof(struct allocExtDesc);
242 aed->lengthAllocDescs =
243 cpu_to_le32(lenalloc);
244 if (!UDF_QUERY_FLAG(sb,
246 sbi->s_udfrev >= 0x0201)
249 udf_update_tag(epos.bh->b_data,
251 mark_buffer_dirty_inode(
256 epos.offset = sizeof(struct allocExtDesc);
258 epos.bh = udf_tread(sb,
259 udf_get_lb_pblock(sb, eloc, 0));
262 (elen + sb->s_blocksize - 1) >>
263 sb->s_blocksize_bits;
265 indirect_ext_len = 1;
267 extent_trunc(inode, &epos, eloc, etype,
269 epos.offset += adsize;
273 if (indirect_ext_len) {
276 udf_free_blocks(sb, inode, epos.block, 0,
280 iinfo->i_lenAlloc = lenalloc;
281 mark_inode_dirty(inode);
283 struct allocExtDesc *aed =
284 (struct allocExtDesc *)(epos.bh->b_data);
285 aed->lengthAllocDescs = cpu_to_le32(lenalloc);
286 if (!UDF_QUERY_FLAG(sb, UDF_FLAG_STRICT) ||
287 sbi->s_udfrev >= 0x0201)
288 udf_update_tag(epos.bh->b_data,
290 sizeof(struct allocExtDesc));
292 udf_update_tag(epos.bh->b_data,
293 sizeof(struct allocExtDesc));
294 mark_buffer_dirty_inode(epos.bh, inode);
297 } else if (inode->i_size) {
299 kernel_long_ad extent;
302 * OK, there is not extent covering inode->i_size and
303 * no extent above inode->i_size => truncate is
304 * extending the file by 'offset' blocks.
308 udf_file_entry_alloc_offset(inode)) ||
309 (epos.bh && epos.offset ==
310 sizeof(struct allocExtDesc))) {
311 /* File has no extents at all or has empty last
312 * indirect extent! Create a fake extent... */
313 extent.extLocation.logicalBlockNum = 0;
314 extent.extLocation.partitionReferenceNum = 0;
316 EXT_NOT_RECORDED_NOT_ALLOCATED;
318 epos.offset -= adsize;
319 etype = udf_next_aext(inode, &epos,
321 &extent.extLength, 0);
322 extent.extLength |= etype << 30;
324 udf_extend_file(inode, &epos, &extent,
327 (sb->s_blocksize - 1)) != 0));
330 iinfo->i_lenExtents = inode->i_size;