source: mainline/uspace/lib/ext4/libext4_extent.c@ 9104bb52

lfn serial ticket/834-toolchain-update topic/msim-upgrade topic/simplify-dev-export
Last change on this file since 9104bb52 was 9104bb52, checked in by Frantisek Princ <frantisek.princ@…>, 14 years ago

changes according to reading inode data with extent

  • Property mode set to 100644
File size: 9.3 KB
Line 
1/*
2 * Copyright (c) 2011 Frantisek Princ
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * - Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * - Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * - The name of the author may not be used to endorse or promote products
15 * derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29/** @addtogroup libext4
30 * @{
31 */
32
33/**
34 * @file libext4_extent.c
35 * @brief Ext4 extent structures operations.
36 */
37
38#include <byteorder.h>
39#include <errno.h>
40#include <malloc.h>
41#include "libext4.h"
42
43uint32_t ext4_extent_get_first_block(ext4_extent_t *extent)
44{
45 return uint32_t_le2host(extent->first_block);
46}
47
48void ext4_extent_set_first_block(ext4_extent_t *extent, uint32_t first_block)
49{
50 extent->first_block = host2uint32_t_le(first_block);
51}
52
53uint16_t ext4_extent_get_block_count(ext4_extent_t *extent)
54{
55 return uint16_t_le2host(extent->block_count);
56}
57
58void ext4_extent_set_block_count(ext4_extent_t *extent, uint16_t block_count)
59{
60 extent->block_count = host2uint16_t_le(block_count);
61}
62
63uint64_t ext4_extent_get_start(ext4_extent_t *extent)
64{
65 return ((uint64_t)uint16_t_le2host(extent->start_hi)) << 32 |
66 ((uint64_t)uint32_t_le2host(extent->start_lo));
67}
68
69void ext4_extent_set_start(ext4_extent_t *extent, uint64_t start)
70{
71 extent->start_lo = host2uint32_t_le((start << 32) >> 32);
72 extent->start_hi = host2uint16_t_le((uint16_t)(start >> 32));
73}
74
75uint32_t ext4_extent_index_get_first_block(ext4_extent_index_t *index)
76{
77 return uint32_t_le2host(index->first_block);
78}
79
80void ext4_extent_index_set_first_block(ext4_extent_index_t *index,
81 uint32_t first)
82{
83 index->first_block = host2uint32_t_le(first);
84}
85
86uint64_t ext4_extent_index_get_leaf(ext4_extent_index_t *index)
87{
88 return ((uint64_t)uint16_t_le2host(index->leaf_hi)) << 32 |
89 ((uint64_t)uint32_t_le2host(index->leaf_lo));
90}
91
92void ext4_extent_index_set_leaf(ext4_extent_index_t *index, uint64_t leaf)
93{
94 index->leaf_lo = host2uint32_t_le((leaf << 32) >> 32);
95 index->leaf_hi = host2uint16_t_le((uint16_t)(leaf >> 32));
96}
97
98uint16_t ext4_extent_header_get_magic(ext4_extent_header_t *header)
99{
100 return uint16_t_le2host(header->magic);
101}
102
103void ext4_extent_header_set_magic(ext4_extent_header_t *header, uint16_t magic)
104{
105 header->magic = host2uint16_t_le(magic);
106}
107
108uint16_t ext4_extent_header_get_entries_count(ext4_extent_header_t *header)
109{
110 return uint16_t_le2host(header->entries_count);
111}
112
113void ext4_extent_header_set_entries_count(ext4_extent_header_t *header,
114 uint16_t count)
115{
116 header->entries_count = host2uint16_t_le(count);
117}
118
119uint16_t ext4_extent_header_get_max_entries_count(ext4_extent_header_t *header)
120{
121 return uint16_t_le2host(header->max_entries_count);
122}
123
124void ext4_extent_header_set_max_entries_count(ext4_extent_header_t *header,
125 uint16_t max_count)
126{
127 header->max_entries_count = host2uint16_t_le(max_count);
128}
129
130uint16_t ext4_extent_header_get_depth(ext4_extent_header_t *header)
131{
132 return uint16_t_le2host(header->depth);
133}
134
135void ext4_extent_header_set_depth(ext4_extent_header_t *header, uint16_t depth)
136{
137 header->depth = host2uint16_t_le(depth);
138}
139
140uint32_t ext4_extent_header_get_generation(ext4_extent_header_t *header)
141{
142 return uint32_t_le2host(header->generation);
143}
144
145void ext4_extent_header_set_generation(ext4_extent_header_t *header,
146 uint32_t generation)
147{
148 header->generation = host2uint32_t_le(generation);
149}
150
151//static void ext4_extent_binsearch_idx(ext4_extent_path_t *path, uint32_t iblock)
152//{
153// ext4_extent_header_t *header = path->header;
154// ext4_extent_index_t *r, *l, *m;
155//
156// uint16_t entries_count = ext4_extent_header_get_entries_count(header);
157// l = EXT4_EXTENT_FIRST_INDEX(header) + 1;
158// r = l + entries_count - 1;
159//
160// while (l <= r) {
161// m = l + (r - l) / 2;
162// uint32_t block = ext4_extent_index_get_first_block(m);
163// if (iblock < block) {
164// r = m - 1;
165// } else {
166// l = m + 1;
167// }
168// }
169//
170// path->index = l - 1;
171//}
172//
173//static void ext4_extent_binsearch(ext4_extent_path_t *path, uint32_t iblock)
174//{
175// ext4_extent_header_t *header = path->header;
176// ext4_extent_t *r, *l, *m;
177//
178// uint16_t entries_count = ext4_extent_header_get_entries_count(header);
179//
180// if (entries_count == 0) {
181// // this leaf is empty
182// return;
183// }
184//
185// l = EXT4_EXTENT_FIRST(header) + 1;
186// r = l + entries_count - 1;
187//
188// while (l <= r) {
189// m = l + (r - l) / 2;
190// uint32_t block = ext4_extent_get_first_block(m);
191// if (iblock < block) {
192// r = m - 1;
193// } else {
194// l = m + 1;
195// }
196// }
197//
198// path->extent = l - 1;
199//
200//}
201
202static int ext4_extent_find_extent(ext4_filesystem_t *fs, ext4_inode_ref_t *inode_ref, uint32_t iblock, ext4_extent_t **ret_extent)
203{
204 int rc;
205
206 block_t* block = NULL;
207
208 ext4_extent_header_t *header = ext4_inode_get_extent_header(inode_ref->inode);
209 while (ext4_extent_header_get_depth(header) != 0) {
210
211 ext4_extent_index_t *extent_index = EXT4_EXTENT_FIRST_INDEX(header);
212
213 for (uint16_t i = 0; i < ext4_extent_header_get_entries_count(header); ++i) {
214 if (iblock >= ext4_extent_index_get_first_block(extent_index)) {
215
216 uint64_t child = ext4_extent_index_get_leaf(extent_index);
217
218 if (block != NULL) {
219 block_put(block);
220 }
221
222 rc = block_get(&block, fs->device, child, BLOCK_FLAGS_NONE);
223 if (rc != EOK) {
224 return rc;
225 }
226
227 header = (ext4_extent_header_t *)block->data;
228 break;
229 }
230 }
231 }
232
233 ext4_extent_t *extent = EXT4_EXTENT_FIRST(header);
234// uint64_t phys_block = 0;
235
236 for (uint16_t i = 0; i < ext4_extent_header_get_entries_count(header); ++i) {
237
238 uint32_t first_block = ext4_extent_get_first_block(extent);
239 uint16_t block_count = ext4_extent_get_block_count(extent);
240
241 if ((iblock >= first_block) && (iblock < first_block + block_count)) {
242 break;
243 }
244 // Go to the next extent
245 ++extent;
246 }
247
248 *ret_extent = extent;
249
250 return EOK;
251}
252
253int ext4_extent_find_block(ext4_filesystem_t *fs,
254 ext4_inode_ref_t *inode_ref, uint32_t iblock, uint32_t *fblock)
255{
256 int rc;
257
258 ext4_extent_t *extent = NULL;
259 rc = ext4_extent_find_extent(fs, inode_ref, iblock, &extent);
260 if (rc != EOK) {
261 return rc;
262 }
263
264 uint32_t phys_block;
265 phys_block = ext4_extent_get_start(extent) + iblock;
266 phys_block -= ext4_extent_get_first_block(extent);
267
268
269 *fblock = phys_block;
270
271 return EOK;
272
273
274// ext4_extent_header_t *eh =
275// ext4_inode_get_extent_header(inode_ref->inode);
276//
277// uint16_t depth = ext4_extent_header_get_depth(eh);
278//
279// ext4_extent_path_t *tmp_path;
280//
281// // Added 2 for possible tree growing
282// tmp_path = malloc(sizeof(ext4_extent_path_t) * (depth + 2));
283// if (tmp_path == NULL) {
284// *path = NULL;
285// return ENOMEM;
286// }
287//
288// tmp_path[0].block = inode_ref->block;
289// tmp_path[0].header = eh;
290//
291// uint16_t pos = 0;
292// while (ext4_extent_header_get_depth(eh) != 0) {
293//
294// EXT4FS_DBG("count == \%u", ext4_extent_header_get_entries_count(eh));
295//
296// ext4_extent_binsearch_idx(tmp_path + pos, iblock);
297//
298// uint32_t offset = (void *)tmp_path[pos].index - (void *)EXT4_EXTENT_FIRST_INDEX(eh);
299//
300// EXT4FS_DBG("offset = \%u", offset);
301//
302// EXT4FS_DBG("first block = \%u, leaf = \%u",
303// ext4_extent_index_get_first_block(tmp_path[pos].index),
304// (uint32_t)ext4_extent_index_get_leaf(tmp_path[pos].index));
305//
306// tmp_path[pos].depth = depth;
307// tmp_path[pos].extent = NULL;
308//
309// assert(tmp_path[pos].index != NULL);
310//
311// uint64_t fblock = ext4_extent_index_get_leaf(tmp_path[pos].index);
312//
313// EXT4FS_DBG("fblock = \%u", (uint32_t)fblock);
314//
315// block_t *block;
316// rc = block_get(&block, fs->device, fblock, BLOCK_FLAGS_NONE);
317// if (rc != EOK) {
318// // TODO cleanup
319// EXT4FS_DBG("ERRRR");
320// return rc;
321// }
322//
323// EXT4FS_DBG("block loaded");
324//
325// pos++;
326//
327// eh = (ext4_extent_header_t *)block->data;
328// tmp_path[pos].block = block;
329// tmp_path[pos].header = eh;
330//
331// }
332//
333// tmp_path[pos].depth = 0;
334// tmp_path[pos].extent = NULL;
335// tmp_path[pos].index = NULL;
336//
337// EXT4FS_DBG("pos = \%u", pos);
338//
339// /* find extent */
340// ext4_extent_binsearch(tmp_path + pos, iblock);
341//
342// EXT4FS_DBG("after binsearch in extent");
343//
344// /* if not an empty leaf */
345// if (tmp_path[pos].extent) {
346// EXT4FS_DBG("nonempty leaf");
347//
348//// uint64_t fblock = ext4_extent_get_start(tmp_path[pos].extent);
349//// block_t *block;
350//// rc = block_get(&block, fs->device, fblock, BLOCK_FLAGS_NONE);
351//// if (rc != EOK) {
352//// // TODO cleanup
353//// }
354//// tmp_path[pos].block = block;
355// }
356//
357// *path = tmp_path;
358//
359// return EOK;
360}
361
362/**
363 * @}
364 */
Note: See TracBrowser for help on using the repository browser.