summaryrefslogtreecommitdiffstats
path: root/block/partitions/aix.c
blob: 007f95eea0e1a9b6b79751ce6f109d151daa12f4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
// SPDX-License-Identifier: GPL-2.0
/*
 *  fs/partitions/aix.c
 *
 *  Copyright (C) 2012-2013 Philippe De Muyter <phdm@macqel.be>
 */

#include "check.h"
#include "aix.h"

struct lvm_rec {
	char lvm_id[4]; /* "_LVM" */
	char reserved4[16];
	__be32 lvmarea_len;
	__be32 vgda_len;
	__be32 vgda_psn[2];
	char reserved36[10];
	__be16 pp_size; /* log2(pp_size) */
	char reserved46[12];
	__be16 version;
	};

struct vgda {
	__be32 secs;
	__be32 usec;
	char reserved8[16];
	__be16 numlvs;
	__be16 maxlvs;
	__be16 pp_size;
	__be16 numpvs;
	__be16 total_vgdas;
	__be16 vgda_size;
	};

struct lvd {
	__be16 lv_ix;
	__be16 res2;
	__be16 res4;
	__be16 maxsize;
	__be16 lv_state;
	__be16 mirror;
	__be16 mirror_policy;
	__be16 num_lps;
	__be16 res10[8];
	};

struct lvname {
	char name[64];
	};

struct ppe {
	__be16 lv_ix;
	unsigned short res2;
	unsigned short res4;
	__be16 lp_ix;
	unsigned short res8[12];
	};

struct pvd {
	char reserved0[16];
	__be16 pp_count;
	char reserved18[2];
	__be32 psn_part1;
	char reserved24[8];
	struct ppe ppe[1016];
	};

#define LVM_MAXLVS 256

/**
 * last_lba(): return number of last logical block of device
 * @bdev: block device
 *
 * Description: Returns last LBA value on success, 0 on error.
 * This is stored (by sd and ide-geometry) in
 *  the part[0] entry for this disk, and is the number of
 *  physical sectors available on the disk.
 */
static u64 last_lba(struct block_device *bdev)
{
	if (!bdev || !bdev->bd_inode)
		return 0;
	return (bdev->bd_inode->i_size >> 9) - 1ULL;
}

/**
 * read_lba(): Read bytes from disk, starting at given LBA
 * @state
 * @lba
 * @buffer
 * @count
 *
 * Description:  Reads @count bytes from @state->bdev into @buffer.
 * Returns number of bytes read on success, 0 on error.
 */
static size_t read_lba(struct parsed_partitions *state, u64 lba, u8 *buffer,
			size_t count)
{
	size_t totalreadcount = 0;

	if (!buffer || lba + count / 512 > last_lba(state->bdev))
		return 0;

	while (count) {
		int copied = 512;
		Sector sect;
		unsigned char *data = read_part_sector(state, lba++, &sect);
		if (!data)
			break;
		if (copied > count)
			copied = count;
		memcpy(buffer, data, copied);
		put_dev_sector(sect);
		buffer += copied;
		totalreadcount += copied;
		count -= copied;
	}
	return totalreadcount;
}

/**
 * alloc_pvd(): reads physical volume descriptor
 * @state
 * @lba
 *
 * Description: Returns pvd on success,  NULL on error.
 * Allocates space for pvd and fill it with disk blocks at @lba
 * Notes: remember to free pvd when you're done!
 */
static struct pvd *alloc_pvd(struct parsed_partitions *state, u32 lba)
{
	size_t count = sizeof(struct pvd);
	struct pvd *p;

	p = kmalloc(count, GFP_KERNEL);
	if (!p)
		return NULL;

	if (read_lba(state, lba, (u8 *) p, count) < count) {
		kfree(p);
		return NULL;
	}
	return p;
}

/**
 * alloc_lvn(): reads logical volume names
 * @state
 * @lba
 *
 * Description: Returns lvn on success,  NULL on error.
 * Allocates space for lvn and fill it with disk blocks at @lba
 * Notes: remember to free lvn when you're done!
 */
static struct lvname *alloc_lvn(struct parsed_partitions *state, u32 lba)
{
	size_t count = sizeof(struct lvname) * LVM_MAXLVS;
	struct lvname *p;

	p = kmalloc(count, GFP_KERNEL);
	if (!p)
		return NULL;

	if (read_lba(state, lba, (u8 *) p, count) < count) {
		kfree(p);
		return NULL;
	}
	return p;
}

int aix_partition(struct parsed_partitions *state)
{
	int ret = 0;
	Sector sect;
	unsigned char *d;
	u32 pp_bytes_size;
	u32 pp_blocks_size = 0;
	u32 vgda_sector = 0;
	u32 vgda_len = 0;
	int numlvs = 0;
	struct pvd *pvd;
	struct lv_info {
		unsigned short pps_per_lv;
		unsigned short pps_found;
		unsigned char lv_is_contiguous;
	} *lvip;
	struct lvname *n = NULL;

	d = read_part_sector(state, 7, &sect);
	if (d) {
		struct lvm_rec *p = (struct lvm_rec *)d;
		u16 lvm_version = be16_to_cpu(p->version);
		char tmp[64];

		if (lvm_version == 1) {
			int pp_size_log2 = be16_to_cpu(p->pp_size);

			pp_bytes_size = 1 << pp_size_log2;
			pp_blocks_size = pp_bytes_size / 512;
			snprintf(tmp, sizeof(tmp),
				" AIX LVM header version %u found\n",
				lvm_version);
			vgda_len = be32_to_cpu(p->vgda_len);
			vgda_sector = be32_to_cpu(p->vgda_psn[0]);
		} else {
			snprintf(tmp, sizeof(tmp),
				" unsupported AIX LVM version %d found\n",
				lvm_version);
		}
		strlcat(state->pp_buf, tmp, PAGE_SIZE);
		put_dev_sector(sect);
	}
	if (vgda_sector && (d = read_part_sector(state, vgda_sector, &sect))) {
		struct vgda *p = (struct vgda *)d;

		numlvs = be16_to_cpu(p->numlvs);
		put_dev_sector(sect);
	}
	lvip = kcalloc(state->limit, sizeof(struct lv_info), GFP_KERNEL);
	if (!lvip)
		return 0;
	if (numlvs && (d = read_part_sector(state, vgda_sector + 1, &sect))) {
		struct lvd *p = (struct lvd *)d;
		int i;

		n = alloc_lvn(state, vgda_sector + vgda_len - 33);
		if (n) {
			int foundlvs = 0;

			for (i = 0; foundlvs < numlvs && i < state->limit; i += 1) {
				lvip[i].pps_per_lv = be16_to_cpu(p[i].num_lps);
				if (lvip[i].pps_per_lv)
					foundlvs += 1;
			}
		}
		put_dev_sector(sect);
	}
	pvd = alloc_pvd(state, vgda_sector + 17);
	if (pvd) {
		int numpps = be16_to_cpu(pvd->pp_count);
		int psn_part1 = be32_to_cpu(pvd->psn_part1);
		int i;
		int cur_lv_ix = -1;
		int next_lp_ix = 1;
		int lp_ix;

		for (i = 0; i < numpps; i += 1) {
			struct ppe *p = pvd->ppe + i;
			unsigned int lv_ix;

			lp_ix = be16_to_cpu(p->lp_ix);
			if (!lp_ix) {
				next_lp_ix = 1;
				continue;
			}
			lv_ix = be16_to_cpu(p->lv_ix) - 1;
			if (lv_ix >= state->limit) {
				cur_lv_ix = -1;
				continue;
			}
			lvip[lv_ix].pps_found += 1;
			if (lp_ix == 1) {
				cur_lv_ix = lv_ix;
				next_lp_ix = 1;
			} else if (lv_ix != cur_lv_ix || lp_ix != next_lp_ix) {
				next_lp_ix = 1;
				continue;
			}
			if (lp_ix == lvip[lv_ix].pps_per_lv) {
				char tmp[70];

				put_partition(state, lv_ix + 1,
				  (i + 1 - lp_ix) * pp_blocks_size + psn_part1,
				  lvip[lv_ix].pps_per_lv * pp_blocks_size);
				snprintf(tmp, sizeof(tmp), " <%s>\n",
					 n[lv_ix].name);
				strlcat(state->pp_buf, tmp, PAGE_SIZE);
				lvip[lv_ix].lv_is_contiguous = 1;
				ret = 1;
				next_lp_ix = 1;
			} else
				next_lp_ix += 1;
		}
		for (i = 0; i < state->limit; i += 1)
			if (lvip[i].pps_found && !lvip[i].lv_is_contiguous)
				pr_warn("partition %s (%u pp's found) is "
					"not contiguous\n",
					n[i].name, lvip[i].pps_found);
		kfree(pvd);
	}
	kfree(n);
	kfree(lvip);
	return ret;
}
OpenPOWER on IntegriCloud