root / block / qcow2-cluster.c @ 73f5e313
History | View | Annotate | Download (27 kB)
1 | 45aba42f | Kevin Wolf | /*
|
---|---|---|---|
2 | 45aba42f | Kevin Wolf | * Block driver for the QCOW version 2 format
|
3 | 45aba42f | Kevin Wolf | *
|
4 | 45aba42f | Kevin Wolf | * Copyright (c) 2004-2006 Fabrice Bellard
|
5 | 45aba42f | Kevin Wolf | *
|
6 | 45aba42f | Kevin Wolf | * Permission is hereby granted, free of charge, to any person obtaining a copy
|
7 | 45aba42f | Kevin Wolf | * of this software and associated documentation files (the "Software"), to deal
|
8 | 45aba42f | Kevin Wolf | * in the Software without restriction, including without limitation the rights
|
9 | 45aba42f | Kevin Wolf | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
10 | 45aba42f | Kevin Wolf | * copies of the Software, and to permit persons to whom the Software is
|
11 | 45aba42f | Kevin Wolf | * furnished to do so, subject to the following conditions:
|
12 | 45aba42f | Kevin Wolf | *
|
13 | 45aba42f | Kevin Wolf | * The above copyright notice and this permission notice shall be included in
|
14 | 45aba42f | Kevin Wolf | * all copies or substantial portions of the Software.
|
15 | 45aba42f | Kevin Wolf | *
|
16 | 45aba42f | Kevin Wolf | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
17 | 45aba42f | Kevin Wolf | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
18 | 45aba42f | Kevin Wolf | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
|
19 | 45aba42f | Kevin Wolf | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
20 | 45aba42f | Kevin Wolf | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
21 | 45aba42f | Kevin Wolf | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
22 | 45aba42f | Kevin Wolf | * THE SOFTWARE.
|
23 | 45aba42f | Kevin Wolf | */
|
24 | 45aba42f | Kevin Wolf | |
25 | 45aba42f | Kevin Wolf | #include <zlib.h> |
26 | 45aba42f | Kevin Wolf | |
27 | 45aba42f | Kevin Wolf | #include "qemu-common.h" |
28 | 45aba42f | Kevin Wolf | #include "block_int.h" |
29 | 45aba42f | Kevin Wolf | #include "block/qcow2.h" |
30 | 45aba42f | Kevin Wolf | |
31 | 72893756 | Stefan Hajnoczi | int qcow2_grow_l1_table(BlockDriverState *bs, int min_size, bool exact_size) |
32 | 45aba42f | Kevin Wolf | { |
33 | 45aba42f | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
34 | 45aba42f | Kevin Wolf | int new_l1_size, new_l1_size2, ret, i;
|
35 | 45aba42f | Kevin Wolf | uint64_t *new_l1_table; |
36 | 5d757b56 | Kevin Wolf | int64_t new_l1_table_offset; |
37 | 45aba42f | Kevin Wolf | uint8_t data[12];
|
38 | 45aba42f | Kevin Wolf | |
39 | 72893756 | Stefan Hajnoczi | if (min_size <= s->l1_size)
|
40 | 45aba42f | Kevin Wolf | return 0; |
41 | 72893756 | Stefan Hajnoczi | |
42 | 72893756 | Stefan Hajnoczi | if (exact_size) {
|
43 | 72893756 | Stefan Hajnoczi | new_l1_size = min_size; |
44 | 72893756 | Stefan Hajnoczi | } else {
|
45 | 72893756 | Stefan Hajnoczi | /* Bump size up to reduce the number of times we have to grow */
|
46 | 72893756 | Stefan Hajnoczi | new_l1_size = s->l1_size; |
47 | 72893756 | Stefan Hajnoczi | if (new_l1_size == 0) { |
48 | 72893756 | Stefan Hajnoczi | new_l1_size = 1;
|
49 | 72893756 | Stefan Hajnoczi | } |
50 | 72893756 | Stefan Hajnoczi | while (min_size > new_l1_size) {
|
51 | 72893756 | Stefan Hajnoczi | new_l1_size = (new_l1_size * 3 + 1) / 2; |
52 | 72893756 | Stefan Hajnoczi | } |
53 | 45aba42f | Kevin Wolf | } |
54 | 72893756 | Stefan Hajnoczi | |
55 | 45aba42f | Kevin Wolf | #ifdef DEBUG_ALLOC2
|
56 | 35ee5e39 | Frediano Ziglio | fprintf(stderr, "grow l1_table from %d to %d\n", s->l1_size, new_l1_size);
|
57 | 45aba42f | Kevin Wolf | #endif
|
58 | 45aba42f | Kevin Wolf | |
59 | 45aba42f | Kevin Wolf | new_l1_size2 = sizeof(uint64_t) * new_l1_size;
|
60 | 7267c094 | Anthony Liguori | new_l1_table = g_malloc0(align_offset(new_l1_size2, 512));
|
61 | 45aba42f | Kevin Wolf | memcpy(new_l1_table, s->l1_table, s->l1_size * sizeof(uint64_t));
|
62 | 45aba42f | Kevin Wolf | |
63 | 45aba42f | Kevin Wolf | /* write new table (align to cluster) */
|
64 | 66f82cee | Kevin Wolf | BLKDBG_EVENT(bs->file, BLKDBG_L1_GROW_ALLOC_TABLE); |
65 | ed6ccf0f | Kevin Wolf | new_l1_table_offset = qcow2_alloc_clusters(bs, new_l1_size2); |
66 | 5d757b56 | Kevin Wolf | if (new_l1_table_offset < 0) { |
67 | 7267c094 | Anthony Liguori | g_free(new_l1_table); |
68 | 5d757b56 | Kevin Wolf | return new_l1_table_offset;
|
69 | 5d757b56 | Kevin Wolf | } |
70 | 29c1a730 | Kevin Wolf | |
71 | 29c1a730 | Kevin Wolf | ret = qcow2_cache_flush(bs, s->refcount_block_cache); |
72 | 29c1a730 | Kevin Wolf | if (ret < 0) { |
73 | 80fa3341 | Kevin Wolf | goto fail;
|
74 | 29c1a730 | Kevin Wolf | } |
75 | 45aba42f | Kevin Wolf | |
76 | 66f82cee | Kevin Wolf | BLKDBG_EVENT(bs->file, BLKDBG_L1_GROW_WRITE_TABLE); |
77 | 45aba42f | Kevin Wolf | for(i = 0; i < s->l1_size; i++) |
78 | 45aba42f | Kevin Wolf | new_l1_table[i] = cpu_to_be64(new_l1_table[i]); |
79 | 8b3b7206 | Kevin Wolf | ret = bdrv_pwrite_sync(bs->file, new_l1_table_offset, new_l1_table, new_l1_size2); |
80 | 8b3b7206 | Kevin Wolf | if (ret < 0) |
81 | 45aba42f | Kevin Wolf | goto fail;
|
82 | 45aba42f | Kevin Wolf | for(i = 0; i < s->l1_size; i++) |
83 | 45aba42f | Kevin Wolf | new_l1_table[i] = be64_to_cpu(new_l1_table[i]); |
84 | 45aba42f | Kevin Wolf | |
85 | 45aba42f | Kevin Wolf | /* set new table */
|
86 | 66f82cee | Kevin Wolf | BLKDBG_EVENT(bs->file, BLKDBG_L1_GROW_ACTIVATE_TABLE); |
87 | 45aba42f | Kevin Wolf | cpu_to_be32w((uint32_t*)data, new_l1_size); |
88 | 653df36b | Aurelien Jarno | cpu_to_be64wu((uint64_t*)(data + 4), new_l1_table_offset);
|
89 | 8b3b7206 | Kevin Wolf | ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, l1_size), data,sizeof(data));
|
90 | 8b3b7206 | Kevin Wolf | if (ret < 0) { |
91 | 45aba42f | Kevin Wolf | goto fail;
|
92 | fb8fa77c | Kevin Wolf | } |
93 | 7267c094 | Anthony Liguori | g_free(s->l1_table); |
94 | ed6ccf0f | Kevin Wolf | qcow2_free_clusters(bs, s->l1_table_offset, s->l1_size * sizeof(uint64_t));
|
95 | 45aba42f | Kevin Wolf | s->l1_table_offset = new_l1_table_offset; |
96 | 45aba42f | Kevin Wolf | s->l1_table = new_l1_table; |
97 | 45aba42f | Kevin Wolf | s->l1_size = new_l1_size; |
98 | 45aba42f | Kevin Wolf | return 0; |
99 | 45aba42f | Kevin Wolf | fail:
|
100 | 7267c094 | Anthony Liguori | g_free(new_l1_table); |
101 | fb8fa77c | Kevin Wolf | qcow2_free_clusters(bs, new_l1_table_offset, new_l1_size2); |
102 | 8b3b7206 | Kevin Wolf | return ret;
|
103 | 45aba42f | Kevin Wolf | } |
104 | 45aba42f | Kevin Wolf | |
105 | 45aba42f | Kevin Wolf | /*
|
106 | 45aba42f | Kevin Wolf | * l2_load
|
107 | 45aba42f | Kevin Wolf | *
|
108 | 45aba42f | Kevin Wolf | * Loads a L2 table into memory. If the table is in the cache, the cache
|
109 | 45aba42f | Kevin Wolf | * is used; otherwise the L2 table is loaded from the image file.
|
110 | 45aba42f | Kevin Wolf | *
|
111 | 45aba42f | Kevin Wolf | * Returns a pointer to the L2 table on success, or NULL if the read from
|
112 | 45aba42f | Kevin Wolf | * the image file failed.
|
113 | 45aba42f | Kevin Wolf | */
|
114 | 45aba42f | Kevin Wolf | |
115 | 55c17e98 | Kevin Wolf | static int l2_load(BlockDriverState *bs, uint64_t l2_offset, |
116 | 55c17e98 | Kevin Wolf | uint64_t **l2_table) |
117 | 45aba42f | Kevin Wolf | { |
118 | 45aba42f | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
119 | 55c17e98 | Kevin Wolf | int ret;
|
120 | 45aba42f | Kevin Wolf | |
121 | 29c1a730 | Kevin Wolf | ret = qcow2_cache_get(bs, s->l2_table_cache, l2_offset, (void**) l2_table);
|
122 | 45aba42f | Kevin Wolf | |
123 | 29c1a730 | Kevin Wolf | return ret;
|
124 | 45aba42f | Kevin Wolf | } |
125 | 45aba42f | Kevin Wolf | |
126 | 45aba42f | Kevin Wolf | /*
|
127 | 6583e3c7 | Kevin Wolf | * Writes one sector of the L1 table to the disk (can't update single entries
|
128 | 6583e3c7 | Kevin Wolf | * and we really don't want bdrv_pread to perform a read-modify-write)
|
129 | 6583e3c7 | Kevin Wolf | */
|
130 | 6583e3c7 | Kevin Wolf | #define L1_ENTRIES_PER_SECTOR (512 / 8) |
131 | 66f82cee | Kevin Wolf | static int write_l1_entry(BlockDriverState *bs, int l1_index) |
132 | 6583e3c7 | Kevin Wolf | { |
133 | 66f82cee | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
134 | 6583e3c7 | Kevin Wolf | uint64_t buf[L1_ENTRIES_PER_SECTOR]; |
135 | 6583e3c7 | Kevin Wolf | int l1_start_index;
|
136 | f7defcb6 | Kevin Wolf | int i, ret;
|
137 | 6583e3c7 | Kevin Wolf | |
138 | 6583e3c7 | Kevin Wolf | l1_start_index = l1_index & ~(L1_ENTRIES_PER_SECTOR - 1);
|
139 | 6583e3c7 | Kevin Wolf | for (i = 0; i < L1_ENTRIES_PER_SECTOR; i++) { |
140 | 6583e3c7 | Kevin Wolf | buf[i] = cpu_to_be64(s->l1_table[l1_start_index + i]); |
141 | 6583e3c7 | Kevin Wolf | } |
142 | 6583e3c7 | Kevin Wolf | |
143 | 66f82cee | Kevin Wolf | BLKDBG_EVENT(bs->file, BLKDBG_L1_UPDATE); |
144 | 8b3b7206 | Kevin Wolf | ret = bdrv_pwrite_sync(bs->file, s->l1_table_offset + 8 * l1_start_index,
|
145 | f7defcb6 | Kevin Wolf | buf, sizeof(buf));
|
146 | f7defcb6 | Kevin Wolf | if (ret < 0) { |
147 | f7defcb6 | Kevin Wolf | return ret;
|
148 | 6583e3c7 | Kevin Wolf | } |
149 | 6583e3c7 | Kevin Wolf | |
150 | 6583e3c7 | Kevin Wolf | return 0; |
151 | 6583e3c7 | Kevin Wolf | } |
152 | 6583e3c7 | Kevin Wolf | |
153 | 6583e3c7 | Kevin Wolf | /*
|
154 | 45aba42f | Kevin Wolf | * l2_allocate
|
155 | 45aba42f | Kevin Wolf | *
|
156 | 45aba42f | Kevin Wolf | * Allocate a new l2 entry in the file. If l1_index points to an already
|
157 | 45aba42f | Kevin Wolf | * used entry in the L2 table (i.e. we are doing a copy on write for the L2
|
158 | 45aba42f | Kevin Wolf | * table) copy the contents of the old L2 table into the newly allocated one.
|
159 | 45aba42f | Kevin Wolf | * Otherwise the new table is initialized with zeros.
|
160 | 45aba42f | Kevin Wolf | *
|
161 | 45aba42f | Kevin Wolf | */
|
162 | 45aba42f | Kevin Wolf | |
163 | c46e1167 | Kevin Wolf | static int l2_allocate(BlockDriverState *bs, int l1_index, uint64_t **table) |
164 | 45aba42f | Kevin Wolf | { |
165 | 45aba42f | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
166 | 6583e3c7 | Kevin Wolf | uint64_t old_l2_offset; |
167 | f4f0d391 | Kevin Wolf | uint64_t *l2_table; |
168 | f4f0d391 | Kevin Wolf | int64_t l2_offset; |
169 | c46e1167 | Kevin Wolf | int ret;
|
170 | 45aba42f | Kevin Wolf | |
171 | 45aba42f | Kevin Wolf | old_l2_offset = s->l1_table[l1_index]; |
172 | 45aba42f | Kevin Wolf | |
173 | 45aba42f | Kevin Wolf | /* allocate a new l2 entry */
|
174 | 45aba42f | Kevin Wolf | |
175 | ed6ccf0f | Kevin Wolf | l2_offset = qcow2_alloc_clusters(bs, s->l2_size * sizeof(uint64_t));
|
176 | 5d757b56 | Kevin Wolf | if (l2_offset < 0) { |
177 | c46e1167 | Kevin Wolf | return l2_offset;
|
178 | 5d757b56 | Kevin Wolf | } |
179 | 29c1a730 | Kevin Wolf | |
180 | 29c1a730 | Kevin Wolf | ret = qcow2_cache_flush(bs, s->refcount_block_cache); |
181 | 29c1a730 | Kevin Wolf | if (ret < 0) { |
182 | 29c1a730 | Kevin Wolf | goto fail;
|
183 | 29c1a730 | Kevin Wolf | } |
184 | 45aba42f | Kevin Wolf | |
185 | 45aba42f | Kevin Wolf | /* allocate a new entry in the l2 cache */
|
186 | 45aba42f | Kevin Wolf | |
187 | 29c1a730 | Kevin Wolf | ret = qcow2_cache_get_empty(bs, s->l2_table_cache, l2_offset, (void**) table);
|
188 | 29c1a730 | Kevin Wolf | if (ret < 0) { |
189 | 29c1a730 | Kevin Wolf | return ret;
|
190 | 29c1a730 | Kevin Wolf | } |
191 | 29c1a730 | Kevin Wolf | |
192 | 29c1a730 | Kevin Wolf | l2_table = *table; |
193 | 45aba42f | Kevin Wolf | |
194 | 45aba42f | Kevin Wolf | if (old_l2_offset == 0) { |
195 | 45aba42f | Kevin Wolf | /* if there was no old l2 table, clear the new table */
|
196 | 45aba42f | Kevin Wolf | memset(l2_table, 0, s->l2_size * sizeof(uint64_t)); |
197 | 45aba42f | Kevin Wolf | } else {
|
198 | 29c1a730 | Kevin Wolf | uint64_t* old_table; |
199 | 29c1a730 | Kevin Wolf | |
200 | 45aba42f | Kevin Wolf | /* if there was an old l2 table, read it from the disk */
|
201 | 66f82cee | Kevin Wolf | BLKDBG_EVENT(bs->file, BLKDBG_L2_ALLOC_COW_READ); |
202 | 29c1a730 | Kevin Wolf | ret = qcow2_cache_get(bs, s->l2_table_cache, old_l2_offset, |
203 | 29c1a730 | Kevin Wolf | (void**) &old_table);
|
204 | 29c1a730 | Kevin Wolf | if (ret < 0) { |
205 | 29c1a730 | Kevin Wolf | goto fail;
|
206 | 29c1a730 | Kevin Wolf | } |
207 | 29c1a730 | Kevin Wolf | |
208 | 29c1a730 | Kevin Wolf | memcpy(l2_table, old_table, s->cluster_size); |
209 | 29c1a730 | Kevin Wolf | |
210 | 29c1a730 | Kevin Wolf | ret = qcow2_cache_put(bs, s->l2_table_cache, (void**) &old_table);
|
211 | c46e1167 | Kevin Wolf | if (ret < 0) { |
212 | 175e1152 | Kevin Wolf | goto fail;
|
213 | c46e1167 | Kevin Wolf | } |
214 | 45aba42f | Kevin Wolf | } |
215 | 29c1a730 | Kevin Wolf | |
216 | 45aba42f | Kevin Wolf | /* write the l2 table to the file */
|
217 | 66f82cee | Kevin Wolf | BLKDBG_EVENT(bs->file, BLKDBG_L2_ALLOC_WRITE); |
218 | 29c1a730 | Kevin Wolf | |
219 | 29c1a730 | Kevin Wolf | qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_table); |
220 | 29c1a730 | Kevin Wolf | ret = qcow2_cache_flush(bs, s->l2_table_cache); |
221 | c46e1167 | Kevin Wolf | if (ret < 0) { |
222 | 175e1152 | Kevin Wolf | goto fail;
|
223 | 175e1152 | Kevin Wolf | } |
224 | 175e1152 | Kevin Wolf | |
225 | 175e1152 | Kevin Wolf | /* update the L1 entry */
|
226 | 175e1152 | Kevin Wolf | s->l1_table[l1_index] = l2_offset | QCOW_OFLAG_COPIED; |
227 | 175e1152 | Kevin Wolf | ret = write_l1_entry(bs, l1_index); |
228 | 175e1152 | Kevin Wolf | if (ret < 0) { |
229 | 175e1152 | Kevin Wolf | goto fail;
|
230 | c46e1167 | Kevin Wolf | } |
231 | 45aba42f | Kevin Wolf | |
232 | c46e1167 | Kevin Wolf | *table = l2_table; |
233 | c46e1167 | Kevin Wolf | return 0; |
234 | 175e1152 | Kevin Wolf | |
235 | 175e1152 | Kevin Wolf | fail:
|
236 | 29c1a730 | Kevin Wolf | qcow2_cache_put(bs, s->l2_table_cache, (void**) table);
|
237 | 68dba0bf | Kevin Wolf | s->l1_table[l1_index] = old_l2_offset; |
238 | 175e1152 | Kevin Wolf | return ret;
|
239 | 45aba42f | Kevin Wolf | } |
240 | 45aba42f | Kevin Wolf | |
241 | 45aba42f | Kevin Wolf | static int count_contiguous_clusters(uint64_t nb_clusters, int cluster_size, |
242 | 45aba42f | Kevin Wolf | uint64_t *l2_table, uint64_t start, uint64_t mask) |
243 | 45aba42f | Kevin Wolf | { |
244 | 45aba42f | Kevin Wolf | int i;
|
245 | 45aba42f | Kevin Wolf | uint64_t offset = be64_to_cpu(l2_table[0]) & ~mask;
|
246 | 45aba42f | Kevin Wolf | |
247 | 45aba42f | Kevin Wolf | if (!offset)
|
248 | 45aba42f | Kevin Wolf | return 0; |
249 | 45aba42f | Kevin Wolf | |
250 | 45aba42f | Kevin Wolf | for (i = start; i < start + nb_clusters; i++)
|
251 | 80ee15a6 | Kevin Wolf | if (offset + (uint64_t) i * cluster_size != (be64_to_cpu(l2_table[i]) & ~mask))
|
252 | 45aba42f | Kevin Wolf | break;
|
253 | 45aba42f | Kevin Wolf | |
254 | 45aba42f | Kevin Wolf | return (i - start);
|
255 | 45aba42f | Kevin Wolf | } |
256 | 45aba42f | Kevin Wolf | |
257 | 45aba42f | Kevin Wolf | static int count_contiguous_free_clusters(uint64_t nb_clusters, uint64_t *l2_table) |
258 | 45aba42f | Kevin Wolf | { |
259 | 45aba42f | Kevin Wolf | int i = 0; |
260 | 45aba42f | Kevin Wolf | |
261 | 45aba42f | Kevin Wolf | while(nb_clusters-- && l2_table[i] == 0) |
262 | 45aba42f | Kevin Wolf | i++; |
263 | 45aba42f | Kevin Wolf | |
264 | 45aba42f | Kevin Wolf | return i;
|
265 | 45aba42f | Kevin Wolf | } |
266 | 45aba42f | Kevin Wolf | |
267 | 45aba42f | Kevin Wolf | /* The crypt function is compatible with the linux cryptoloop
|
268 | 45aba42f | Kevin Wolf | algorithm for < 4 GB images. NOTE: out_buf == in_buf is
|
269 | 45aba42f | Kevin Wolf | supported */
|
270 | ed6ccf0f | Kevin Wolf | void qcow2_encrypt_sectors(BDRVQcowState *s, int64_t sector_num,
|
271 | ed6ccf0f | Kevin Wolf | uint8_t *out_buf, const uint8_t *in_buf,
|
272 | ed6ccf0f | Kevin Wolf | int nb_sectors, int enc, |
273 | ed6ccf0f | Kevin Wolf | const AES_KEY *key)
|
274 | 45aba42f | Kevin Wolf | { |
275 | 45aba42f | Kevin Wolf | union {
|
276 | 45aba42f | Kevin Wolf | uint64_t ll[2];
|
277 | 45aba42f | Kevin Wolf | uint8_t b[16];
|
278 | 45aba42f | Kevin Wolf | } ivec; |
279 | 45aba42f | Kevin Wolf | int i;
|
280 | 45aba42f | Kevin Wolf | |
281 | 45aba42f | Kevin Wolf | for(i = 0; i < nb_sectors; i++) { |
282 | 45aba42f | Kevin Wolf | ivec.ll[0] = cpu_to_le64(sector_num);
|
283 | 45aba42f | Kevin Wolf | ivec.ll[1] = 0; |
284 | 45aba42f | Kevin Wolf | AES_cbc_encrypt(in_buf, out_buf, 512, key,
|
285 | 45aba42f | Kevin Wolf | ivec.b, enc); |
286 | 45aba42f | Kevin Wolf | sector_num++; |
287 | 45aba42f | Kevin Wolf | in_buf += 512;
|
288 | 45aba42f | Kevin Wolf | out_buf += 512;
|
289 | 45aba42f | Kevin Wolf | } |
290 | 45aba42f | Kevin Wolf | } |
291 | 45aba42f | Kevin Wolf | |
292 | aef4acb6 | Stefan Hajnoczi | static int coroutine_fn copy_sectors(BlockDriverState *bs, |
293 | aef4acb6 | Stefan Hajnoczi | uint64_t start_sect, |
294 | aef4acb6 | Stefan Hajnoczi | uint64_t cluster_offset, |
295 | aef4acb6 | Stefan Hajnoczi | int n_start, int n_end) |
296 | 45aba42f | Kevin Wolf | { |
297 | 45aba42f | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
298 | aef4acb6 | Stefan Hajnoczi | QEMUIOVector qiov; |
299 | aef4acb6 | Stefan Hajnoczi | struct iovec iov;
|
300 | 45aba42f | Kevin Wolf | int n, ret;
|
301 | 1b9f1491 | Kevin Wolf | |
302 | 1b9f1491 | Kevin Wolf | /*
|
303 | 1b9f1491 | Kevin Wolf | * If this is the last cluster and it is only partially used, we must only
|
304 | 1b9f1491 | Kevin Wolf | * copy until the end of the image, or bdrv_check_request will fail for the
|
305 | 1b9f1491 | Kevin Wolf | * bdrv_read/write calls below.
|
306 | 1b9f1491 | Kevin Wolf | */
|
307 | 1b9f1491 | Kevin Wolf | if (start_sect + n_end > bs->total_sectors) {
|
308 | 1b9f1491 | Kevin Wolf | n_end = bs->total_sectors - start_sect; |
309 | 1b9f1491 | Kevin Wolf | } |
310 | 45aba42f | Kevin Wolf | |
311 | 45aba42f | Kevin Wolf | n = n_end - n_start; |
312 | 1b9f1491 | Kevin Wolf | if (n <= 0) { |
313 | 45aba42f | Kevin Wolf | return 0; |
314 | 1b9f1491 | Kevin Wolf | } |
315 | 1b9f1491 | Kevin Wolf | |
316 | aef4acb6 | Stefan Hajnoczi | iov.iov_len = n * BDRV_SECTOR_SIZE; |
317 | aef4acb6 | Stefan Hajnoczi | iov.iov_base = qemu_blockalign(bs, iov.iov_len); |
318 | aef4acb6 | Stefan Hajnoczi | |
319 | aef4acb6 | Stefan Hajnoczi | qemu_iovec_init_external(&qiov, &iov, 1);
|
320 | 1b9f1491 | Kevin Wolf | |
321 | 66f82cee | Kevin Wolf | BLKDBG_EVENT(bs->file, BLKDBG_COW_READ); |
322 | aef4acb6 | Stefan Hajnoczi | |
323 | aef4acb6 | Stefan Hajnoczi | /* Call .bdrv_co_readv() directly instead of using the public block-layer
|
324 | aef4acb6 | Stefan Hajnoczi | * interface. This avoids double I/O throttling and request tracking,
|
325 | aef4acb6 | Stefan Hajnoczi | * which can lead to deadlock when block layer copy-on-read is enabled.
|
326 | aef4acb6 | Stefan Hajnoczi | */
|
327 | aef4acb6 | Stefan Hajnoczi | ret = bs->drv->bdrv_co_readv(bs, start_sect + n_start, n, &qiov); |
328 | 1b9f1491 | Kevin Wolf | if (ret < 0) { |
329 | 1b9f1491 | Kevin Wolf | goto out;
|
330 | 1b9f1491 | Kevin Wolf | } |
331 | 1b9f1491 | Kevin Wolf | |
332 | 45aba42f | Kevin Wolf | if (s->crypt_method) {
|
333 | ed6ccf0f | Kevin Wolf | qcow2_encrypt_sectors(s, start_sect + n_start, |
334 | aef4acb6 | Stefan Hajnoczi | iov.iov_base, iov.iov_base, n, 1,
|
335 | 45aba42f | Kevin Wolf | &s->aes_encrypt_key); |
336 | 45aba42f | Kevin Wolf | } |
337 | 1b9f1491 | Kevin Wolf | |
338 | 66f82cee | Kevin Wolf | BLKDBG_EVENT(bs->file, BLKDBG_COW_WRITE); |
339 | aef4acb6 | Stefan Hajnoczi | ret = bdrv_co_writev(bs->file, (cluster_offset >> 9) + n_start, n, &qiov);
|
340 | 1b9f1491 | Kevin Wolf | if (ret < 0) { |
341 | 1b9f1491 | Kevin Wolf | goto out;
|
342 | 1b9f1491 | Kevin Wolf | } |
343 | 1b9f1491 | Kevin Wolf | |
344 | 1b9f1491 | Kevin Wolf | ret = 0;
|
345 | 1b9f1491 | Kevin Wolf | out:
|
346 | aef4acb6 | Stefan Hajnoczi | qemu_vfree(iov.iov_base); |
347 | 1b9f1491 | Kevin Wolf | return ret;
|
348 | 45aba42f | Kevin Wolf | } |
349 | 45aba42f | Kevin Wolf | |
350 | 45aba42f | Kevin Wolf | |
351 | 45aba42f | Kevin Wolf | /*
|
352 | 45aba42f | Kevin Wolf | * get_cluster_offset
|
353 | 45aba42f | Kevin Wolf | *
|
354 | 1c46efaa | Kevin Wolf | * For a given offset of the disk image, find the cluster offset in
|
355 | 1c46efaa | Kevin Wolf | * qcow2 file. The offset is stored in *cluster_offset.
|
356 | 45aba42f | Kevin Wolf | *
|
357 | d57237f2 | Devin Nakamura | * on entry, *num is the number of contiguous sectors we'd like to
|
358 | 45aba42f | Kevin Wolf | * access following offset.
|
359 | 45aba42f | Kevin Wolf | *
|
360 | d57237f2 | Devin Nakamura | * on exit, *num is the number of contiguous sectors we can read.
|
361 | 45aba42f | Kevin Wolf | *
|
362 | 1c46efaa | Kevin Wolf | * Return 0, if the offset is found
|
363 | 1c46efaa | Kevin Wolf | * Return -errno, otherwise.
|
364 | 45aba42f | Kevin Wolf | *
|
365 | 45aba42f | Kevin Wolf | */
|
366 | 45aba42f | Kevin Wolf | |
367 | 1c46efaa | Kevin Wolf | int qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset,
|
368 | 1c46efaa | Kevin Wolf | int *num, uint64_t *cluster_offset)
|
369 | 45aba42f | Kevin Wolf | { |
370 | 45aba42f | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
371 | 80ee15a6 | Kevin Wolf | unsigned int l1_index, l2_index; |
372 | 1c46efaa | Kevin Wolf | uint64_t l2_offset, *l2_table; |
373 | 45aba42f | Kevin Wolf | int l1_bits, c;
|
374 | 80ee15a6 | Kevin Wolf | unsigned int index_in_cluster, nb_clusters; |
375 | 80ee15a6 | Kevin Wolf | uint64_t nb_available, nb_needed; |
376 | 55c17e98 | Kevin Wolf | int ret;
|
377 | 45aba42f | Kevin Wolf | |
378 | 45aba42f | Kevin Wolf | index_in_cluster = (offset >> 9) & (s->cluster_sectors - 1); |
379 | 45aba42f | Kevin Wolf | nb_needed = *num + index_in_cluster; |
380 | 45aba42f | Kevin Wolf | |
381 | 45aba42f | Kevin Wolf | l1_bits = s->l2_bits + s->cluster_bits; |
382 | 45aba42f | Kevin Wolf | |
383 | 45aba42f | Kevin Wolf | /* compute how many bytes there are between the offset and
|
384 | 45aba42f | Kevin Wolf | * the end of the l1 entry
|
385 | 45aba42f | Kevin Wolf | */
|
386 | 45aba42f | Kevin Wolf | |
387 | 80ee15a6 | Kevin Wolf | nb_available = (1ULL << l1_bits) - (offset & ((1ULL << l1_bits) - 1)); |
388 | 45aba42f | Kevin Wolf | |
389 | 45aba42f | Kevin Wolf | /* compute the number of available sectors */
|
390 | 45aba42f | Kevin Wolf | |
391 | 45aba42f | Kevin Wolf | nb_available = (nb_available >> 9) + index_in_cluster;
|
392 | 45aba42f | Kevin Wolf | |
393 | 45aba42f | Kevin Wolf | if (nb_needed > nb_available) {
|
394 | 45aba42f | Kevin Wolf | nb_needed = nb_available; |
395 | 45aba42f | Kevin Wolf | } |
396 | 45aba42f | Kevin Wolf | |
397 | 1c46efaa | Kevin Wolf | *cluster_offset = 0;
|
398 | 45aba42f | Kevin Wolf | |
399 | 45aba42f | Kevin Wolf | /* seek the the l2 offset in the l1 table */
|
400 | 45aba42f | Kevin Wolf | |
401 | 45aba42f | Kevin Wolf | l1_index = offset >> l1_bits; |
402 | 45aba42f | Kevin Wolf | if (l1_index >= s->l1_size)
|
403 | 45aba42f | Kevin Wolf | goto out;
|
404 | 45aba42f | Kevin Wolf | |
405 | 45aba42f | Kevin Wolf | l2_offset = s->l1_table[l1_index]; |
406 | 45aba42f | Kevin Wolf | |
407 | 45aba42f | Kevin Wolf | /* seek the l2 table of the given l2 offset */
|
408 | 45aba42f | Kevin Wolf | |
409 | 45aba42f | Kevin Wolf | if (!l2_offset)
|
410 | 45aba42f | Kevin Wolf | goto out;
|
411 | 45aba42f | Kevin Wolf | |
412 | 45aba42f | Kevin Wolf | /* load the l2 table in memory */
|
413 | 45aba42f | Kevin Wolf | |
414 | 45aba42f | Kevin Wolf | l2_offset &= ~QCOW_OFLAG_COPIED; |
415 | 55c17e98 | Kevin Wolf | ret = l2_load(bs, l2_offset, &l2_table); |
416 | 55c17e98 | Kevin Wolf | if (ret < 0) { |
417 | 55c17e98 | Kevin Wolf | return ret;
|
418 | 1c46efaa | Kevin Wolf | } |
419 | 45aba42f | Kevin Wolf | |
420 | 45aba42f | Kevin Wolf | /* find the cluster offset for the given disk offset */
|
421 | 45aba42f | Kevin Wolf | |
422 | 45aba42f | Kevin Wolf | l2_index = (offset >> s->cluster_bits) & (s->l2_size - 1);
|
423 | 1c46efaa | Kevin Wolf | *cluster_offset = be64_to_cpu(l2_table[l2_index]); |
424 | 45aba42f | Kevin Wolf | nb_clusters = size_to_clusters(s, nb_needed << 9);
|
425 | 45aba42f | Kevin Wolf | |
426 | 1c46efaa | Kevin Wolf | if (!*cluster_offset) {
|
427 | 45aba42f | Kevin Wolf | /* how many empty clusters ? */
|
428 | 45aba42f | Kevin Wolf | c = count_contiguous_free_clusters(nb_clusters, &l2_table[l2_index]); |
429 | 45aba42f | Kevin Wolf | } else {
|
430 | 45aba42f | Kevin Wolf | /* how many allocated clusters ? */
|
431 | 45aba42f | Kevin Wolf | c = count_contiguous_clusters(nb_clusters, s->cluster_size, |
432 | 45aba42f | Kevin Wolf | &l2_table[l2_index], 0, QCOW_OFLAG_COPIED);
|
433 | 45aba42f | Kevin Wolf | } |
434 | 45aba42f | Kevin Wolf | |
435 | 29c1a730 | Kevin Wolf | qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
|
436 | 29c1a730 | Kevin Wolf | |
437 | 45aba42f | Kevin Wolf | nb_available = (c * s->cluster_sectors); |
438 | 45aba42f | Kevin Wolf | out:
|
439 | 45aba42f | Kevin Wolf | if (nb_available > nb_needed)
|
440 | 45aba42f | Kevin Wolf | nb_available = nb_needed; |
441 | 45aba42f | Kevin Wolf | |
442 | 45aba42f | Kevin Wolf | *num = nb_available - index_in_cluster; |
443 | 45aba42f | Kevin Wolf | |
444 | 1c46efaa | Kevin Wolf | *cluster_offset &=~QCOW_OFLAG_COPIED; |
445 | 1c46efaa | Kevin Wolf | return 0; |
446 | 45aba42f | Kevin Wolf | } |
447 | 45aba42f | Kevin Wolf | |
448 | 45aba42f | Kevin Wolf | /*
|
449 | 45aba42f | Kevin Wolf | * get_cluster_table
|
450 | 45aba42f | Kevin Wolf | *
|
451 | 45aba42f | Kevin Wolf | * for a given disk offset, load (and allocate if needed)
|
452 | 45aba42f | Kevin Wolf | * the l2 table.
|
453 | 45aba42f | Kevin Wolf | *
|
454 | 45aba42f | Kevin Wolf | * the l2 table offset in the qcow2 file and the cluster index
|
455 | 45aba42f | Kevin Wolf | * in the l2 table are given to the caller.
|
456 | 45aba42f | Kevin Wolf | *
|
457 | 1e3e8f1a | Kevin Wolf | * Returns 0 on success, -errno in failure case
|
458 | 45aba42f | Kevin Wolf | */
|
459 | 45aba42f | Kevin Wolf | static int get_cluster_table(BlockDriverState *bs, uint64_t offset, |
460 | 45aba42f | Kevin Wolf | uint64_t **new_l2_table, |
461 | 45aba42f | Kevin Wolf | uint64_t *new_l2_offset, |
462 | 45aba42f | Kevin Wolf | int *new_l2_index)
|
463 | 45aba42f | Kevin Wolf | { |
464 | 45aba42f | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
465 | 80ee15a6 | Kevin Wolf | unsigned int l1_index, l2_index; |
466 | c46e1167 | Kevin Wolf | uint64_t l2_offset; |
467 | c46e1167 | Kevin Wolf | uint64_t *l2_table = NULL;
|
468 | 80ee15a6 | Kevin Wolf | int ret;
|
469 | 45aba42f | Kevin Wolf | |
470 | 45aba42f | Kevin Wolf | /* seek the the l2 offset in the l1 table */
|
471 | 45aba42f | Kevin Wolf | |
472 | 45aba42f | Kevin Wolf | l1_index = offset >> (s->l2_bits + s->cluster_bits); |
473 | 45aba42f | Kevin Wolf | if (l1_index >= s->l1_size) {
|
474 | 72893756 | Stefan Hajnoczi | ret = qcow2_grow_l1_table(bs, l1_index + 1, false); |
475 | 1e3e8f1a | Kevin Wolf | if (ret < 0) { |
476 | 1e3e8f1a | Kevin Wolf | return ret;
|
477 | 1e3e8f1a | Kevin Wolf | } |
478 | 45aba42f | Kevin Wolf | } |
479 | 45aba42f | Kevin Wolf | l2_offset = s->l1_table[l1_index]; |
480 | 45aba42f | Kevin Wolf | |
481 | 45aba42f | Kevin Wolf | /* seek the l2 table of the given l2 offset */
|
482 | 45aba42f | Kevin Wolf | |
483 | 45aba42f | Kevin Wolf | if (l2_offset & QCOW_OFLAG_COPIED) {
|
484 | 45aba42f | Kevin Wolf | /* load the l2 table in memory */
|
485 | 45aba42f | Kevin Wolf | l2_offset &= ~QCOW_OFLAG_COPIED; |
486 | 55c17e98 | Kevin Wolf | ret = l2_load(bs, l2_offset, &l2_table); |
487 | 55c17e98 | Kevin Wolf | if (ret < 0) { |
488 | 55c17e98 | Kevin Wolf | return ret;
|
489 | 1e3e8f1a | Kevin Wolf | } |
490 | 45aba42f | Kevin Wolf | } else {
|
491 | 16fde5f2 | Kevin Wolf | /* First allocate a new L2 table (and do COW if needed) */
|
492 | c46e1167 | Kevin Wolf | ret = l2_allocate(bs, l1_index, &l2_table); |
493 | c46e1167 | Kevin Wolf | if (ret < 0) { |
494 | c46e1167 | Kevin Wolf | return ret;
|
495 | 1e3e8f1a | Kevin Wolf | } |
496 | 16fde5f2 | Kevin Wolf | |
497 | 16fde5f2 | Kevin Wolf | /* Then decrease the refcount of the old table */
|
498 | 16fde5f2 | Kevin Wolf | if (l2_offset) {
|
499 | 16fde5f2 | Kevin Wolf | qcow2_free_clusters(bs, l2_offset, s->l2_size * sizeof(uint64_t));
|
500 | 16fde5f2 | Kevin Wolf | } |
501 | 45aba42f | Kevin Wolf | l2_offset = s->l1_table[l1_index] & ~QCOW_OFLAG_COPIED; |
502 | 45aba42f | Kevin Wolf | } |
503 | 45aba42f | Kevin Wolf | |
504 | 45aba42f | Kevin Wolf | /* find the cluster offset for the given disk offset */
|
505 | 45aba42f | Kevin Wolf | |
506 | 45aba42f | Kevin Wolf | l2_index = (offset >> s->cluster_bits) & (s->l2_size - 1);
|
507 | 45aba42f | Kevin Wolf | |
508 | 45aba42f | Kevin Wolf | *new_l2_table = l2_table; |
509 | 45aba42f | Kevin Wolf | *new_l2_offset = l2_offset; |
510 | 45aba42f | Kevin Wolf | *new_l2_index = l2_index; |
511 | 45aba42f | Kevin Wolf | |
512 | 1e3e8f1a | Kevin Wolf | return 0; |
513 | 45aba42f | Kevin Wolf | } |
514 | 45aba42f | Kevin Wolf | |
515 | 45aba42f | Kevin Wolf | /*
|
516 | 45aba42f | Kevin Wolf | * alloc_compressed_cluster_offset
|
517 | 45aba42f | Kevin Wolf | *
|
518 | 45aba42f | Kevin Wolf | * For a given offset of the disk image, return cluster offset in
|
519 | 45aba42f | Kevin Wolf | * qcow2 file.
|
520 | 45aba42f | Kevin Wolf | *
|
521 | 45aba42f | Kevin Wolf | * If the offset is not found, allocate a new compressed cluster.
|
522 | 45aba42f | Kevin Wolf | *
|
523 | 45aba42f | Kevin Wolf | * Return the cluster offset if successful,
|
524 | 45aba42f | Kevin Wolf | * Return 0, otherwise.
|
525 | 45aba42f | Kevin Wolf | *
|
526 | 45aba42f | Kevin Wolf | */
|
527 | 45aba42f | Kevin Wolf | |
528 | ed6ccf0f | Kevin Wolf | uint64_t qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs, |
529 | ed6ccf0f | Kevin Wolf | uint64_t offset, |
530 | ed6ccf0f | Kevin Wolf | int compressed_size)
|
531 | 45aba42f | Kevin Wolf | { |
532 | 45aba42f | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
533 | 45aba42f | Kevin Wolf | int l2_index, ret;
|
534 | f4f0d391 | Kevin Wolf | uint64_t l2_offset, *l2_table; |
535 | f4f0d391 | Kevin Wolf | int64_t cluster_offset; |
536 | 45aba42f | Kevin Wolf | int nb_csectors;
|
537 | 45aba42f | Kevin Wolf | |
538 | 45aba42f | Kevin Wolf | ret = get_cluster_table(bs, offset, &l2_table, &l2_offset, &l2_index); |
539 | 1e3e8f1a | Kevin Wolf | if (ret < 0) { |
540 | 45aba42f | Kevin Wolf | return 0; |
541 | 1e3e8f1a | Kevin Wolf | } |
542 | 45aba42f | Kevin Wolf | |
543 | 45aba42f | Kevin Wolf | cluster_offset = be64_to_cpu(l2_table[l2_index]); |
544 | 8f1efd00 | Kevin Wolf | if (cluster_offset & QCOW_OFLAG_COPIED) {
|
545 | 8f1efd00 | Kevin Wolf | qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
|
546 | 8f1efd00 | Kevin Wolf | return 0; |
547 | 8f1efd00 | Kevin Wolf | } |
548 | 45aba42f | Kevin Wolf | |
549 | 45aba42f | Kevin Wolf | if (cluster_offset)
|
550 | ed6ccf0f | Kevin Wolf | qcow2_free_any_clusters(bs, cluster_offset, 1);
|
551 | 45aba42f | Kevin Wolf | |
552 | ed6ccf0f | Kevin Wolf | cluster_offset = qcow2_alloc_bytes(bs, compressed_size); |
553 | 5d757b56 | Kevin Wolf | if (cluster_offset < 0) { |
554 | 29c1a730 | Kevin Wolf | qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
|
555 | 5d757b56 | Kevin Wolf | return 0; |
556 | 5d757b56 | Kevin Wolf | } |
557 | 5d757b56 | Kevin Wolf | |
558 | 45aba42f | Kevin Wolf | nb_csectors = ((cluster_offset + compressed_size - 1) >> 9) - |
559 | 45aba42f | Kevin Wolf | (cluster_offset >> 9);
|
560 | 45aba42f | Kevin Wolf | |
561 | 45aba42f | Kevin Wolf | cluster_offset |= QCOW_OFLAG_COMPRESSED | |
562 | 45aba42f | Kevin Wolf | ((uint64_t)nb_csectors << s->csize_shift); |
563 | 45aba42f | Kevin Wolf | |
564 | 45aba42f | Kevin Wolf | /* update L2 table */
|
565 | 45aba42f | Kevin Wolf | |
566 | 45aba42f | Kevin Wolf | /* compressed clusters never have the copied flag */
|
567 | 45aba42f | Kevin Wolf | |
568 | 66f82cee | Kevin Wolf | BLKDBG_EVENT(bs->file, BLKDBG_L2_UPDATE_COMPRESSED); |
569 | 29c1a730 | Kevin Wolf | qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_table); |
570 | 45aba42f | Kevin Wolf | l2_table[l2_index] = cpu_to_be64(cluster_offset); |
571 | 29c1a730 | Kevin Wolf | ret = qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
|
572 | 79a31189 | Kevin Wolf | if (ret < 0) { |
573 | 29c1a730 | Kevin Wolf | return 0; |
574 | 4c1612d9 | Kevin Wolf | } |
575 | 4c1612d9 | Kevin Wolf | |
576 | 29c1a730 | Kevin Wolf | return cluster_offset;
|
577 | 4c1612d9 | Kevin Wolf | } |
578 | 4c1612d9 | Kevin Wolf | |
579 | 148da7ea | Kevin Wolf | int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m)
|
580 | 45aba42f | Kevin Wolf | { |
581 | 45aba42f | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
582 | 45aba42f | Kevin Wolf | int i, j = 0, l2_index, ret; |
583 | 45aba42f | Kevin Wolf | uint64_t *old_cluster, start_sect, l2_offset, *l2_table; |
584 | 148da7ea | Kevin Wolf | uint64_t cluster_offset = m->cluster_offset; |
585 | 29c1a730 | Kevin Wolf | bool cow = false; |
586 | 45aba42f | Kevin Wolf | |
587 | 45aba42f | Kevin Wolf | if (m->nb_clusters == 0) |
588 | 45aba42f | Kevin Wolf | return 0; |
589 | 45aba42f | Kevin Wolf | |
590 | 7267c094 | Anthony Liguori | old_cluster = g_malloc(m->nb_clusters * sizeof(uint64_t));
|
591 | 45aba42f | Kevin Wolf | |
592 | 45aba42f | Kevin Wolf | /* copy content of unmodified sectors */
|
593 | 45aba42f | Kevin Wolf | start_sect = (m->offset & ~(s->cluster_size - 1)) >> 9; |
594 | 45aba42f | Kevin Wolf | if (m->n_start) {
|
595 | 29c1a730 | Kevin Wolf | cow = true;
|
596 | 1b9f1491 | Kevin Wolf | qemu_co_mutex_unlock(&s->lock); |
597 | 45aba42f | Kevin Wolf | ret = copy_sectors(bs, start_sect, cluster_offset, 0, m->n_start);
|
598 | 1b9f1491 | Kevin Wolf | qemu_co_mutex_lock(&s->lock); |
599 | 45aba42f | Kevin Wolf | if (ret < 0) |
600 | 45aba42f | Kevin Wolf | goto err;
|
601 | 45aba42f | Kevin Wolf | } |
602 | 45aba42f | Kevin Wolf | |
603 | 45aba42f | Kevin Wolf | if (m->nb_available & (s->cluster_sectors - 1)) { |
604 | 45aba42f | Kevin Wolf | uint64_t end = m->nb_available & ~(uint64_t)(s->cluster_sectors - 1);
|
605 | 29c1a730 | Kevin Wolf | cow = true;
|
606 | 1b9f1491 | Kevin Wolf | qemu_co_mutex_unlock(&s->lock); |
607 | 45aba42f | Kevin Wolf | ret = copy_sectors(bs, start_sect + end, cluster_offset + (end << 9),
|
608 | 45aba42f | Kevin Wolf | m->nb_available - end, s->cluster_sectors); |
609 | 1b9f1491 | Kevin Wolf | qemu_co_mutex_lock(&s->lock); |
610 | 45aba42f | Kevin Wolf | if (ret < 0) |
611 | 45aba42f | Kevin Wolf | goto err;
|
612 | 45aba42f | Kevin Wolf | } |
613 | 45aba42f | Kevin Wolf | |
614 | 29c1a730 | Kevin Wolf | /*
|
615 | 29c1a730 | Kevin Wolf | * Update L2 table.
|
616 | 29c1a730 | Kevin Wolf | *
|
617 | 29c1a730 | Kevin Wolf | * Before we update the L2 table to actually point to the new cluster, we
|
618 | 29c1a730 | Kevin Wolf | * need to be sure that the refcounts have been increased and COW was
|
619 | 29c1a730 | Kevin Wolf | * handled.
|
620 | 29c1a730 | Kevin Wolf | */
|
621 | 29c1a730 | Kevin Wolf | if (cow) {
|
622 | 3de0a294 | Kevin Wolf | qcow2_cache_depends_on_flush(s->l2_table_cache); |
623 | 29c1a730 | Kevin Wolf | } |
624 | 29c1a730 | Kevin Wolf | |
625 | 29c1a730 | Kevin Wolf | qcow2_cache_set_dependency(bs, s->l2_table_cache, s->refcount_block_cache); |
626 | 1e3e8f1a | Kevin Wolf | ret = get_cluster_table(bs, m->offset, &l2_table, &l2_offset, &l2_index); |
627 | 1e3e8f1a | Kevin Wolf | if (ret < 0) { |
628 | 45aba42f | Kevin Wolf | goto err;
|
629 | 1e3e8f1a | Kevin Wolf | } |
630 | 29c1a730 | Kevin Wolf | qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_table); |
631 | 45aba42f | Kevin Wolf | |
632 | 45aba42f | Kevin Wolf | for (i = 0; i < m->nb_clusters; i++) { |
633 | 45aba42f | Kevin Wolf | /* if two concurrent writes happen to the same unallocated cluster
|
634 | 45aba42f | Kevin Wolf | * each write allocates separate cluster and writes data concurrently.
|
635 | 45aba42f | Kevin Wolf | * The first one to complete updates l2 table with pointer to its
|
636 | 45aba42f | Kevin Wolf | * cluster the second one has to do RMW (which is done above by
|
637 | 45aba42f | Kevin Wolf | * copy_sectors()), update l2 table with its cluster pointer and free
|
638 | 45aba42f | Kevin Wolf | * old cluster. This is what this loop does */
|
639 | 45aba42f | Kevin Wolf | if(l2_table[l2_index + i] != 0) |
640 | 45aba42f | Kevin Wolf | old_cluster[j++] = l2_table[l2_index + i]; |
641 | 45aba42f | Kevin Wolf | |
642 | 45aba42f | Kevin Wolf | l2_table[l2_index + i] = cpu_to_be64((cluster_offset + |
643 | 45aba42f | Kevin Wolf | (i << s->cluster_bits)) | QCOW_OFLAG_COPIED); |
644 | 45aba42f | Kevin Wolf | } |
645 | 45aba42f | Kevin Wolf | |
646 | 9f8e668e | Kevin Wolf | |
647 | 29c1a730 | Kevin Wolf | ret = qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
|
648 | c835d00f | Kevin Wolf | if (ret < 0) { |
649 | 45aba42f | Kevin Wolf | goto err;
|
650 | 4c1612d9 | Kevin Wolf | } |
651 | 45aba42f | Kevin Wolf | |
652 | 7ec5e6a4 | Kevin Wolf | /*
|
653 | 7ec5e6a4 | Kevin Wolf | * If this was a COW, we need to decrease the refcount of the old cluster.
|
654 | 7ec5e6a4 | Kevin Wolf | * Also flush bs->file to get the right order for L2 and refcount update.
|
655 | 7ec5e6a4 | Kevin Wolf | */
|
656 | 7ec5e6a4 | Kevin Wolf | if (j != 0) { |
657 | 7ec5e6a4 | Kevin Wolf | for (i = 0; i < j; i++) { |
658 | 7ec5e6a4 | Kevin Wolf | qcow2_free_any_clusters(bs, |
659 | 7ec5e6a4 | Kevin Wolf | be64_to_cpu(old_cluster[i]) & ~QCOW_OFLAG_COPIED, 1);
|
660 | 7ec5e6a4 | Kevin Wolf | } |
661 | 7ec5e6a4 | Kevin Wolf | } |
662 | 45aba42f | Kevin Wolf | |
663 | 45aba42f | Kevin Wolf | ret = 0;
|
664 | 45aba42f | Kevin Wolf | err:
|
665 | 7267c094 | Anthony Liguori | g_free(old_cluster); |
666 | 45aba42f | Kevin Wolf | return ret;
|
667 | 45aba42f | Kevin Wolf | } |
668 | 45aba42f | Kevin Wolf | |
669 | 45aba42f | Kevin Wolf | /*
|
670 | 45aba42f | Kevin Wolf | * alloc_cluster_offset
|
671 | 45aba42f | Kevin Wolf | *
|
672 | 148da7ea | Kevin Wolf | * For a given offset of the disk image, return cluster offset in qcow2 file.
|
673 | 45aba42f | Kevin Wolf | * If the offset is not found, allocate a new cluster.
|
674 | 45aba42f | Kevin Wolf | *
|
675 | 148da7ea | Kevin Wolf | * If the cluster was already allocated, m->nb_clusters is set to 0,
|
676 | a7912369 | Frediano Ziglio | * other fields in m are meaningless.
|
677 | 148da7ea | Kevin Wolf | *
|
678 | 148da7ea | Kevin Wolf | * If the cluster is newly allocated, m->nb_clusters is set to the number of
|
679 | 68d100e9 | Kevin Wolf | * contiguous clusters that have been allocated. In this case, the other
|
680 | 68d100e9 | Kevin Wolf | * fields of m are valid and contain information about the first allocated
|
681 | 68d100e9 | Kevin Wolf | * cluster.
|
682 | 45aba42f | Kevin Wolf | *
|
683 | 68d100e9 | Kevin Wolf | * If the request conflicts with another write request in flight, the coroutine
|
684 | 68d100e9 | Kevin Wolf | * is queued and will be reentered when the dependency has completed.
|
685 | 148da7ea | Kevin Wolf | *
|
686 | 148da7ea | Kevin Wolf | * Return 0 on success and -errno in error cases
|
687 | 45aba42f | Kevin Wolf | */
|
688 | f4f0d391 | Kevin Wolf | int qcow2_alloc_cluster_offset(BlockDriverState *bs, uint64_t offset,
|
689 | f4f0d391 | Kevin Wolf | int n_start, int n_end, int *num, QCowL2Meta *m) |
690 | 45aba42f | Kevin Wolf | { |
691 | 45aba42f | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
692 | 45aba42f | Kevin Wolf | int l2_index, ret;
|
693 | 5d757b56 | Kevin Wolf | uint64_t l2_offset, *l2_table; |
694 | 5d757b56 | Kevin Wolf | int64_t cluster_offset; |
695 | 80ee15a6 | Kevin Wolf | unsigned int nb_clusters, i = 0; |
696 | f214978a | Kevin Wolf | QCowL2Meta *old_alloc; |
697 | 45aba42f | Kevin Wolf | |
698 | 45aba42f | Kevin Wolf | ret = get_cluster_table(bs, offset, &l2_table, &l2_offset, &l2_index); |
699 | 1e3e8f1a | Kevin Wolf | if (ret < 0) { |
700 | 148da7ea | Kevin Wolf | return ret;
|
701 | 1e3e8f1a | Kevin Wolf | } |
702 | 45aba42f | Kevin Wolf | |
703 | 68d100e9 | Kevin Wolf | again:
|
704 | 45aba42f | Kevin Wolf | nb_clusters = size_to_clusters(s, n_end << 9);
|
705 | 45aba42f | Kevin Wolf | |
706 | 45aba42f | Kevin Wolf | nb_clusters = MIN(nb_clusters, s->l2_size - l2_index); |
707 | 45aba42f | Kevin Wolf | |
708 | 45aba42f | Kevin Wolf | cluster_offset = be64_to_cpu(l2_table[l2_index]); |
709 | 45aba42f | Kevin Wolf | |
710 | 45aba42f | Kevin Wolf | /* We keep all QCOW_OFLAG_COPIED clusters */
|
711 | 45aba42f | Kevin Wolf | |
712 | 45aba42f | Kevin Wolf | if (cluster_offset & QCOW_OFLAG_COPIED) {
|
713 | 45aba42f | Kevin Wolf | nb_clusters = count_contiguous_clusters(nb_clusters, s->cluster_size, |
714 | 45aba42f | Kevin Wolf | &l2_table[l2_index], 0, 0); |
715 | 45aba42f | Kevin Wolf | |
716 | 45aba42f | Kevin Wolf | cluster_offset &= ~QCOW_OFLAG_COPIED; |
717 | 45aba42f | Kevin Wolf | m->nb_clusters = 0;
|
718 | 45aba42f | Kevin Wolf | |
719 | 45aba42f | Kevin Wolf | goto out;
|
720 | 45aba42f | Kevin Wolf | } |
721 | 45aba42f | Kevin Wolf | |
722 | 45aba42f | Kevin Wolf | /* for the moment, multiple compressed clusters are not managed */
|
723 | 45aba42f | Kevin Wolf | |
724 | 45aba42f | Kevin Wolf | if (cluster_offset & QCOW_OFLAG_COMPRESSED)
|
725 | 45aba42f | Kevin Wolf | nb_clusters = 1;
|
726 | 45aba42f | Kevin Wolf | |
727 | 45aba42f | Kevin Wolf | /* how many available clusters ? */
|
728 | 45aba42f | Kevin Wolf | |
729 | 45aba42f | Kevin Wolf | while (i < nb_clusters) {
|
730 | 45aba42f | Kevin Wolf | i += count_contiguous_clusters(nb_clusters - i, s->cluster_size, |
731 | 45aba42f | Kevin Wolf | &l2_table[l2_index], i, 0);
|
732 | 4805bb66 | Kevin Wolf | if ((i >= nb_clusters) || be64_to_cpu(l2_table[l2_index + i])) {
|
733 | 45aba42f | Kevin Wolf | break;
|
734 | 4805bb66 | Kevin Wolf | } |
735 | 45aba42f | Kevin Wolf | |
736 | 45aba42f | Kevin Wolf | i += count_contiguous_free_clusters(nb_clusters - i, |
737 | 45aba42f | Kevin Wolf | &l2_table[l2_index + i]); |
738 | 4805bb66 | Kevin Wolf | if (i >= nb_clusters) {
|
739 | 4805bb66 | Kevin Wolf | break;
|
740 | 4805bb66 | Kevin Wolf | } |
741 | 45aba42f | Kevin Wolf | |
742 | 45aba42f | Kevin Wolf | cluster_offset = be64_to_cpu(l2_table[l2_index + i]); |
743 | 45aba42f | Kevin Wolf | |
744 | 45aba42f | Kevin Wolf | if ((cluster_offset & QCOW_OFLAG_COPIED) ||
|
745 | 45aba42f | Kevin Wolf | (cluster_offset & QCOW_OFLAG_COMPRESSED)) |
746 | 45aba42f | Kevin Wolf | break;
|
747 | 45aba42f | Kevin Wolf | } |
748 | 4805bb66 | Kevin Wolf | assert(i <= nb_clusters); |
749 | 45aba42f | Kevin Wolf | nb_clusters = i; |
750 | 45aba42f | Kevin Wolf | |
751 | f214978a | Kevin Wolf | /*
|
752 | f214978a | Kevin Wolf | * Check if there already is an AIO write request in flight which allocates
|
753 | f214978a | Kevin Wolf | * the same cluster. In this case we need to wait until the previous
|
754 | f214978a | Kevin Wolf | * request has completed and updated the L2 table accordingly.
|
755 | f214978a | Kevin Wolf | */
|
756 | 72cf2d4f | Blue Swirl | QLIST_FOREACH(old_alloc, &s->cluster_allocs, next_in_flight) { |
757 | f214978a | Kevin Wolf | |
758 | ee18e730 | Frediano Ziglio | uint64_t start = offset >> s->cluster_bits; |
759 | ee18e730 | Frediano Ziglio | uint64_t end = start + nb_clusters; |
760 | ee18e730 | Frediano Ziglio | uint64_t old_start = old_alloc->offset >> s->cluster_bits; |
761 | ee18e730 | Frediano Ziglio | uint64_t old_end = old_start + old_alloc->nb_clusters; |
762 | f214978a | Kevin Wolf | |
763 | ee18e730 | Frediano Ziglio | if (end < old_start || start > old_end) {
|
764 | f214978a | Kevin Wolf | /* No intersection */
|
765 | f214978a | Kevin Wolf | } else {
|
766 | ee18e730 | Frediano Ziglio | if (start < old_start) {
|
767 | f214978a | Kevin Wolf | /* Stop at the start of a running allocation */
|
768 | ee18e730 | Frediano Ziglio | nb_clusters = old_start - start; |
769 | f214978a | Kevin Wolf | } else {
|
770 | f214978a | Kevin Wolf | nb_clusters = 0;
|
771 | f214978a | Kevin Wolf | } |
772 | f214978a | Kevin Wolf | |
773 | f214978a | Kevin Wolf | if (nb_clusters == 0) { |
774 | 68d100e9 | Kevin Wolf | /* Wait for the dependency to complete. We need to recheck
|
775 | 68d100e9 | Kevin Wolf | * the free/allocated clusters when we continue. */
|
776 | 68d100e9 | Kevin Wolf | qemu_co_mutex_unlock(&s->lock); |
777 | 68d100e9 | Kevin Wolf | qemu_co_queue_wait(&old_alloc->dependent_requests); |
778 | 68d100e9 | Kevin Wolf | qemu_co_mutex_lock(&s->lock); |
779 | 68d100e9 | Kevin Wolf | goto again;
|
780 | f214978a | Kevin Wolf | } |
781 | f214978a | Kevin Wolf | } |
782 | f214978a | Kevin Wolf | } |
783 | f214978a | Kevin Wolf | |
784 | f214978a | Kevin Wolf | if (!nb_clusters) {
|
785 | f214978a | Kevin Wolf | abort(); |
786 | f214978a | Kevin Wolf | } |
787 | f214978a | Kevin Wolf | |
788 | 05140499 | Frediano Ziglio | /* save info needed for meta data update */
|
789 | 05140499 | Frediano Ziglio | m->offset = offset; |
790 | 05140499 | Frediano Ziglio | m->n_start = n_start; |
791 | 05140499 | Frediano Ziglio | m->nb_clusters = nb_clusters; |
792 | 05140499 | Frediano Ziglio | |
793 | 72cf2d4f | Blue Swirl | QLIST_INSERT_HEAD(&s->cluster_allocs, m, next_in_flight); |
794 | f214978a | Kevin Wolf | |
795 | 45aba42f | Kevin Wolf | /* allocate a new cluster */
|
796 | 45aba42f | Kevin Wolf | |
797 | ed6ccf0f | Kevin Wolf | cluster_offset = qcow2_alloc_clusters(bs, nb_clusters * s->cluster_size); |
798 | 5d757b56 | Kevin Wolf | if (cluster_offset < 0) { |
799 | 29c1a730 | Kevin Wolf | ret = cluster_offset; |
800 | 29c1a730 | Kevin Wolf | goto fail;
|
801 | 5d757b56 | Kevin Wolf | } |
802 | 45aba42f | Kevin Wolf | |
803 | 45aba42f | Kevin Wolf | out:
|
804 | 29c1a730 | Kevin Wolf | ret = qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
|
805 | 29c1a730 | Kevin Wolf | if (ret < 0) { |
806 | 9e2a3701 | Kevin Wolf | goto fail_put;
|
807 | 29c1a730 | Kevin Wolf | } |
808 | 29c1a730 | Kevin Wolf | |
809 | 45aba42f | Kevin Wolf | m->nb_available = MIN(nb_clusters << (s->cluster_bits - 9), n_end);
|
810 | 148da7ea | Kevin Wolf | m->cluster_offset = cluster_offset; |
811 | 45aba42f | Kevin Wolf | |
812 | 45aba42f | Kevin Wolf | *num = m->nb_available - n_start; |
813 | 45aba42f | Kevin Wolf | |
814 | 148da7ea | Kevin Wolf | return 0; |
815 | 29c1a730 | Kevin Wolf | |
816 | 29c1a730 | Kevin Wolf | fail:
|
817 | 29c1a730 | Kevin Wolf | qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
|
818 | 9e2a3701 | Kevin Wolf | fail_put:
|
819 | 9e2a3701 | Kevin Wolf | QLIST_REMOVE(m, next_in_flight); |
820 | 29c1a730 | Kevin Wolf | return ret;
|
821 | 45aba42f | Kevin Wolf | } |
822 | 45aba42f | Kevin Wolf | |
823 | 45aba42f | Kevin Wolf | static int decompress_buffer(uint8_t *out_buf, int out_buf_size, |
824 | 45aba42f | Kevin Wolf | const uint8_t *buf, int buf_size) |
825 | 45aba42f | Kevin Wolf | { |
826 | 45aba42f | Kevin Wolf | z_stream strm1, *strm = &strm1; |
827 | 45aba42f | Kevin Wolf | int ret, out_len;
|
828 | 45aba42f | Kevin Wolf | |
829 | 45aba42f | Kevin Wolf | memset(strm, 0, sizeof(*strm)); |
830 | 45aba42f | Kevin Wolf | |
831 | 45aba42f | Kevin Wolf | strm->next_in = (uint8_t *)buf; |
832 | 45aba42f | Kevin Wolf | strm->avail_in = buf_size; |
833 | 45aba42f | Kevin Wolf | strm->next_out = out_buf; |
834 | 45aba42f | Kevin Wolf | strm->avail_out = out_buf_size; |
835 | 45aba42f | Kevin Wolf | |
836 | 45aba42f | Kevin Wolf | ret = inflateInit2(strm, -12);
|
837 | 45aba42f | Kevin Wolf | if (ret != Z_OK)
|
838 | 45aba42f | Kevin Wolf | return -1; |
839 | 45aba42f | Kevin Wolf | ret = inflate(strm, Z_FINISH); |
840 | 45aba42f | Kevin Wolf | out_len = strm->next_out - out_buf; |
841 | 45aba42f | Kevin Wolf | if ((ret != Z_STREAM_END && ret != Z_BUF_ERROR) ||
|
842 | 45aba42f | Kevin Wolf | out_len != out_buf_size) { |
843 | 45aba42f | Kevin Wolf | inflateEnd(strm); |
844 | 45aba42f | Kevin Wolf | return -1; |
845 | 45aba42f | Kevin Wolf | } |
846 | 45aba42f | Kevin Wolf | inflateEnd(strm); |
847 | 45aba42f | Kevin Wolf | return 0; |
848 | 45aba42f | Kevin Wolf | } |
849 | 45aba42f | Kevin Wolf | |
850 | 66f82cee | Kevin Wolf | int qcow2_decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset)
|
851 | 45aba42f | Kevin Wolf | { |
852 | 66f82cee | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
853 | 45aba42f | Kevin Wolf | int ret, csize, nb_csectors, sector_offset;
|
854 | 45aba42f | Kevin Wolf | uint64_t coffset; |
855 | 45aba42f | Kevin Wolf | |
856 | 45aba42f | Kevin Wolf | coffset = cluster_offset & s->cluster_offset_mask; |
857 | 45aba42f | Kevin Wolf | if (s->cluster_cache_offset != coffset) {
|
858 | 45aba42f | Kevin Wolf | nb_csectors = ((cluster_offset >> s->csize_shift) & s->csize_mask) + 1;
|
859 | 45aba42f | Kevin Wolf | sector_offset = coffset & 511;
|
860 | 45aba42f | Kevin Wolf | csize = nb_csectors * 512 - sector_offset;
|
861 | 66f82cee | Kevin Wolf | BLKDBG_EVENT(bs->file, BLKDBG_READ_COMPRESSED); |
862 | 66f82cee | Kevin Wolf | ret = bdrv_read(bs->file, coffset >> 9, s->cluster_data, nb_csectors);
|
863 | 45aba42f | Kevin Wolf | if (ret < 0) { |
864 | 8af36488 | Kevin Wolf | return ret;
|
865 | 45aba42f | Kevin Wolf | } |
866 | 45aba42f | Kevin Wolf | if (decompress_buffer(s->cluster_cache, s->cluster_size,
|
867 | 45aba42f | Kevin Wolf | s->cluster_data + sector_offset, csize) < 0) {
|
868 | 8af36488 | Kevin Wolf | return -EIO;
|
869 | 45aba42f | Kevin Wolf | } |
870 | 45aba42f | Kevin Wolf | s->cluster_cache_offset = coffset; |
871 | 45aba42f | Kevin Wolf | } |
872 | 45aba42f | Kevin Wolf | return 0; |
873 | 45aba42f | Kevin Wolf | } |
874 | 5ea929e3 | Kevin Wolf | |
875 | 5ea929e3 | Kevin Wolf | /*
|
876 | 5ea929e3 | Kevin Wolf | * This discards as many clusters of nb_clusters as possible at once (i.e.
|
877 | 5ea929e3 | Kevin Wolf | * all clusters in the same L2 table) and returns the number of discarded
|
878 | 5ea929e3 | Kevin Wolf | * clusters.
|
879 | 5ea929e3 | Kevin Wolf | */
|
880 | 5ea929e3 | Kevin Wolf | static int discard_single_l2(BlockDriverState *bs, uint64_t offset, |
881 | 5ea929e3 | Kevin Wolf | unsigned int nb_clusters) |
882 | 5ea929e3 | Kevin Wolf | { |
883 | 5ea929e3 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
884 | 5ea929e3 | Kevin Wolf | uint64_t l2_offset, *l2_table; |
885 | 5ea929e3 | Kevin Wolf | int l2_index;
|
886 | 5ea929e3 | Kevin Wolf | int ret;
|
887 | 5ea929e3 | Kevin Wolf | int i;
|
888 | 5ea929e3 | Kevin Wolf | |
889 | 5ea929e3 | Kevin Wolf | ret = get_cluster_table(bs, offset, &l2_table, &l2_offset, &l2_index); |
890 | 5ea929e3 | Kevin Wolf | if (ret < 0) { |
891 | 5ea929e3 | Kevin Wolf | return ret;
|
892 | 5ea929e3 | Kevin Wolf | } |
893 | 5ea929e3 | Kevin Wolf | |
894 | 5ea929e3 | Kevin Wolf | /* Limit nb_clusters to one L2 table */
|
895 | 5ea929e3 | Kevin Wolf | nb_clusters = MIN(nb_clusters, s->l2_size - l2_index); |
896 | 5ea929e3 | Kevin Wolf | |
897 | 5ea929e3 | Kevin Wolf | for (i = 0; i < nb_clusters; i++) { |
898 | 5ea929e3 | Kevin Wolf | uint64_t old_offset; |
899 | 5ea929e3 | Kevin Wolf | |
900 | 5ea929e3 | Kevin Wolf | old_offset = be64_to_cpu(l2_table[l2_index + i]); |
901 | 5ea929e3 | Kevin Wolf | old_offset &= ~QCOW_OFLAG_COPIED; |
902 | 5ea929e3 | Kevin Wolf | |
903 | 5ea929e3 | Kevin Wolf | if (old_offset == 0) { |
904 | 5ea929e3 | Kevin Wolf | continue;
|
905 | 5ea929e3 | Kevin Wolf | } |
906 | 5ea929e3 | Kevin Wolf | |
907 | 5ea929e3 | Kevin Wolf | /* First remove L2 entries */
|
908 | 5ea929e3 | Kevin Wolf | qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_table); |
909 | 5ea929e3 | Kevin Wolf | l2_table[l2_index + i] = cpu_to_be64(0);
|
910 | 5ea929e3 | Kevin Wolf | |
911 | 5ea929e3 | Kevin Wolf | /* Then decrease the refcount */
|
912 | 5ea929e3 | Kevin Wolf | qcow2_free_any_clusters(bs, old_offset, 1);
|
913 | 5ea929e3 | Kevin Wolf | } |
914 | 5ea929e3 | Kevin Wolf | |
915 | 5ea929e3 | Kevin Wolf | ret = qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
|
916 | 5ea929e3 | Kevin Wolf | if (ret < 0) { |
917 | 5ea929e3 | Kevin Wolf | return ret;
|
918 | 5ea929e3 | Kevin Wolf | } |
919 | 5ea929e3 | Kevin Wolf | |
920 | 5ea929e3 | Kevin Wolf | return nb_clusters;
|
921 | 5ea929e3 | Kevin Wolf | } |
922 | 5ea929e3 | Kevin Wolf | |
923 | 5ea929e3 | Kevin Wolf | int qcow2_discard_clusters(BlockDriverState *bs, uint64_t offset,
|
924 | 5ea929e3 | Kevin Wolf | int nb_sectors)
|
925 | 5ea929e3 | Kevin Wolf | { |
926 | 5ea929e3 | Kevin Wolf | BDRVQcowState *s = bs->opaque; |
927 | 5ea929e3 | Kevin Wolf | uint64_t end_offset; |
928 | 5ea929e3 | Kevin Wolf | unsigned int nb_clusters; |
929 | 5ea929e3 | Kevin Wolf | int ret;
|
930 | 5ea929e3 | Kevin Wolf | |
931 | 5ea929e3 | Kevin Wolf | end_offset = offset + (nb_sectors << BDRV_SECTOR_BITS); |
932 | 5ea929e3 | Kevin Wolf | |
933 | 5ea929e3 | Kevin Wolf | /* Round start up and end down */
|
934 | 5ea929e3 | Kevin Wolf | offset = align_offset(offset, s->cluster_size); |
935 | 5ea929e3 | Kevin Wolf | end_offset &= ~(s->cluster_size - 1);
|
936 | 5ea929e3 | Kevin Wolf | |
937 | 5ea929e3 | Kevin Wolf | if (offset > end_offset) {
|
938 | 5ea929e3 | Kevin Wolf | return 0; |
939 | 5ea929e3 | Kevin Wolf | } |
940 | 5ea929e3 | Kevin Wolf | |
941 | 5ea929e3 | Kevin Wolf | nb_clusters = size_to_clusters(s, end_offset - offset); |
942 | 5ea929e3 | Kevin Wolf | |
943 | 5ea929e3 | Kevin Wolf | /* Each L2 table is handled by its own loop iteration */
|
944 | 5ea929e3 | Kevin Wolf | while (nb_clusters > 0) { |
945 | 5ea929e3 | Kevin Wolf | ret = discard_single_l2(bs, offset, nb_clusters); |
946 | 5ea929e3 | Kevin Wolf | if (ret < 0) { |
947 | 5ea929e3 | Kevin Wolf | return ret;
|
948 | 5ea929e3 | Kevin Wolf | } |
949 | 5ea929e3 | Kevin Wolf | |
950 | 5ea929e3 | Kevin Wolf | nb_clusters -= ret; |
951 | 5ea929e3 | Kevin Wolf | offset += (ret * s->cluster_size); |
952 | 5ea929e3 | Kevin Wolf | } |
953 | 5ea929e3 | Kevin Wolf | |
954 | 5ea929e3 | Kevin Wolf | return 0; |
955 | 5ea929e3 | Kevin Wolf | } |