1 /*
2 * fs/partitions/aix.c
3 *
4 * Copyright (C) 2012-2013 Philippe De Muyter <phdm@macqel.be>
5 */
6
7 #include "check.h"
8 #include "aix.h"
9
10 struct lvm_rec {
11 char lvm_id[4]; /* "_LVM" */
12 char reserved4[16];
13 __be32 lvmarea_len;
14 __be32 vgda_len;
15 __be32 vgda_psn[2];
16 char reserved36[10];
17 __be16 pp_size; /* log2(pp_size) */
18 char reserved46[12];
19 __be16 version;
20 };
21
22 struct vgda {
23 __be32 secs;
24 __be32 usec;
25 char reserved8[16];
26 __be16 numlvs;
27 __be16 maxlvs;
28 __be16 pp_size;
29 __be16 numpvs;
30 __be16 total_vgdas;
31 __be16 vgda_size;
32 };
33
34 struct lvd {
35 __be16 lv_ix;
36 __be16 res2;
37 __be16 res4;
38 __be16 maxsize;
39 __be16 lv_state;
40 __be16 mirror;
41 __be16 mirror_policy;
42 __be16 num_lps;
43 __be16 res10[8];
44 };
45
46 struct lvname {
47 char name[64];
48 };
49
50 struct ppe {
51 __be16 lv_ix;
52 unsigned short res2;
53 unsigned short res4;
54 __be16 lp_ix;
55 unsigned short res8[12];
56 };
57
58 struct pvd {
59 char reserved0[16];
60 __be16 pp_count;
61 char reserved18[2];
62 __be32 psn_part1;
63 char reserved24[8];
64 struct ppe ppe[1016];
65 };
66
67 #define LVM_MAXLVS 256
68
69 /**
70 * last_lba(): return number of last logical block of device
71 * @bdev: block device
72 *
73 * Description: Returns last LBA value on success, 0 on error.
74 * This is stored (by sd and ide-geometry) in
75 * the part[0] entry for this disk, and is the number of
76 * physical sectors available on the disk.
77 */
last_lba(struct block_device * bdev)78 static u64 last_lba(struct block_device *bdev)
79 {
80 if (!bdev || !bdev->bd_inode)
81 return 0;
82 return (bdev->bd_inode->i_size >> 9) - 1ULL;
83 }
84
85 /**
86 * read_lba(): Read bytes from disk, starting at given LBA
87 * @state
88 * @lba
89 * @buffer
90 * @count
91 *
92 * Description: Reads @count bytes from @state->bdev into @buffer.
93 * Returns number of bytes read on success, 0 on error.
94 */
read_lba(struct parsed_partitions * state,u64 lba,u8 * buffer,size_t count)95 static size_t read_lba(struct parsed_partitions *state, u64 lba, u8 *buffer,
96 size_t count)
97 {
98 size_t totalreadcount = 0;
99
100 if (!buffer || lba + count / 512 > last_lba(state->bdev))
101 return 0;
102
103 while (count) {
104 int copied = 512;
105 Sector sect;
106 unsigned char *data = read_part_sector(state, lba++, §);
107 if (!data)
108 break;
109 if (copied > count)
110 copied = count;
111 memcpy(buffer, data, copied);
112 put_dev_sector(sect);
113 buffer += copied;
114 totalreadcount += copied;
115 count -= copied;
116 }
117 return totalreadcount;
118 }
119
120 /**
121 * alloc_pvd(): reads physical volume descriptor
122 * @state
123 * @lba
124 *
125 * Description: Returns pvd on success, NULL on error.
126 * Allocates space for pvd and fill it with disk blocks at @lba
127 * Notes: remember to free pvd when you're done!
128 */
alloc_pvd(struct parsed_partitions * state,u32 lba)129 static struct pvd *alloc_pvd(struct parsed_partitions *state, u32 lba)
130 {
131 size_t count = sizeof(struct pvd);
132 struct pvd *p;
133
134 p = kmalloc(count, GFP_KERNEL);
135 if (!p)
136 return NULL;
137
138 if (read_lba(state, lba, (u8 *) p, count) < count) {
139 kfree(p);
140 return NULL;
141 }
142 return p;
143 }
144
145 /**
146 * alloc_lvn(): reads logical volume names
147 * @state
148 * @lba
149 *
150 * Description: Returns lvn on success, NULL on error.
151 * Allocates space for lvn and fill it with disk blocks at @lba
152 * Notes: remember to free lvn when you're done!
153 */
alloc_lvn(struct parsed_partitions * state,u32 lba)154 static struct lvname *alloc_lvn(struct parsed_partitions *state, u32 lba)
155 {
156 size_t count = sizeof(struct lvname) * LVM_MAXLVS;
157 struct lvname *p;
158
159 p = kmalloc(count, GFP_KERNEL);
160 if (!p)
161 return NULL;
162
163 if (read_lba(state, lba, (u8 *) p, count) < count) {
164 kfree(p);
165 return NULL;
166 }
167 return p;
168 }
169
aix_partition(struct parsed_partitions * state)170 int aix_partition(struct parsed_partitions *state)
171 {
172 int ret = 0;
173 Sector sect;
174 unsigned char *d;
175 u32 pp_bytes_size;
176 u32 pp_blocks_size = 0;
177 u32 vgda_sector = 0;
178 u32 vgda_len = 0;
179 int numlvs = 0;
180 struct pvd *pvd;
181 struct lv_info {
182 unsigned short pps_per_lv;
183 unsigned short pps_found;
184 unsigned char lv_is_contiguous;
185 } *lvip;
186 struct lvname *n = NULL;
187
188 d = read_part_sector(state, 7, §);
189 if (d) {
190 struct lvm_rec *p = (struct lvm_rec *)d;
191 u16 lvm_version = be16_to_cpu(p->version);
192 char tmp[64];
193
194 if (lvm_version == 1) {
195 int pp_size_log2 = be16_to_cpu(p->pp_size);
196
197 pp_bytes_size = 1 << pp_size_log2;
198 pp_blocks_size = pp_bytes_size / 512;
199 snprintf(tmp, sizeof(tmp),
200 " AIX LVM header version %u found\n",
201 lvm_version);
202 vgda_len = be32_to_cpu(p->vgda_len);
203 vgda_sector = be32_to_cpu(p->vgda_psn[0]);
204 } else {
205 snprintf(tmp, sizeof(tmp),
206 " unsupported AIX LVM version %d found\n",
207 lvm_version);
208 }
209 strlcat(state->pp_buf, tmp, PAGE_SIZE);
210 put_dev_sector(sect);
211 }
212 if (vgda_sector && (d = read_part_sector(state, vgda_sector, §))) {
213 struct vgda *p = (struct vgda *)d;
214
215 numlvs = be16_to_cpu(p->numlvs);
216 put_dev_sector(sect);
217 }
218 lvip = kcalloc(state->limit, sizeof(struct lv_info), GFP_KERNEL);
219 if (!lvip)
220 return 0;
221 if (numlvs && (d = read_part_sector(state, vgda_sector + 1, §))) {
222 struct lvd *p = (struct lvd *)d;
223 int i;
224
225 n = alloc_lvn(state, vgda_sector + vgda_len - 33);
226 if (n) {
227 int foundlvs = 0;
228
229 for (i = 0; foundlvs < numlvs && i < state->limit; i += 1) {
230 lvip[i].pps_per_lv = be16_to_cpu(p[i].num_lps);
231 if (lvip[i].pps_per_lv)
232 foundlvs += 1;
233 }
234 }
235 put_dev_sector(sect);
236 }
237 pvd = alloc_pvd(state, vgda_sector + 17);
238 if (pvd) {
239 int numpps = be16_to_cpu(pvd->pp_count);
240 int psn_part1 = be32_to_cpu(pvd->psn_part1);
241 int i;
242 int cur_lv_ix = -1;
243 int next_lp_ix = 1;
244 int lp_ix;
245
246 for (i = 0; i < numpps; i += 1) {
247 struct ppe *p = pvd->ppe + i;
248 unsigned int lv_ix;
249
250 lp_ix = be16_to_cpu(p->lp_ix);
251 if (!lp_ix) {
252 next_lp_ix = 1;
253 continue;
254 }
255 lv_ix = be16_to_cpu(p->lv_ix) - 1;
256 if (lv_ix >= state->limit) {
257 cur_lv_ix = -1;
258 continue;
259 }
260 lvip[lv_ix].pps_found += 1;
261 if (lp_ix == 1) {
262 cur_lv_ix = lv_ix;
263 next_lp_ix = 1;
264 } else if (lv_ix != cur_lv_ix || lp_ix != next_lp_ix) {
265 next_lp_ix = 1;
266 continue;
267 }
268 if (lp_ix == lvip[lv_ix].pps_per_lv) {
269 char tmp[70];
270
271 put_partition(state, lv_ix + 1,
272 (i + 1 - lp_ix) * pp_blocks_size + psn_part1,
273 lvip[lv_ix].pps_per_lv * pp_blocks_size);
274 snprintf(tmp, sizeof(tmp), " <%s>\n",
275 n[lv_ix].name);
276 strlcat(state->pp_buf, tmp, PAGE_SIZE);
277 lvip[lv_ix].lv_is_contiguous = 1;
278 ret = 1;
279 next_lp_ix = 1;
280 } else
281 next_lp_ix += 1;
282 }
283 for (i = 0; i < state->limit; i += 1)
284 if (lvip[i].pps_found && !lvip[i].lv_is_contiguous)
285 pr_warn("partition %s (%u pp's found) is "
286 "not contiguous\n",
287 n[i].name, lvip[i].pps_found);
288 kfree(pvd);
289 }
290 kfree(n);
291 kfree(lvip);
292 return ret;
293 }
294