summaryrefslogtreecommitdiff
path: root/target/linux/generic/patches-2.6.37/400-rootfs_split.patch
blob: f5f95cfda14860454c95719e28f8954104f7502c (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
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
--- a/drivers/mtd/Kconfig
+++ b/drivers/mtd/Kconfig
@@ -53,6 +53,16 @@ config MTD_PARTITIONS
 	  devices. Partitioning on NFTL 'devices' is a different - that's the
 	  'normal' form of partitioning used on a block device.
 
+config MTD_ROOTFS_ROOT_DEV
+	bool "Automatically set 'rootfs' partition to be root filesystem"
+	depends on MTD_PARTITIONS
+	default y
+
+config MTD_ROOTFS_SPLIT
+	bool "Automatically split 'rootfs' partition for squashfs"
+	depends on MTD_PARTITIONS
+	default y
+
 config MTD_REDBOOT_PARTS
 	tristate "RedBoot partition table parsing"
 	depends on MTD_PARTITIONS
--- a/drivers/mtd/mtdpart.c
+++ b/drivers/mtd/mtdpart.c
@@ -29,6 +29,8 @@
 #include <linux/kmod.h>
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/partitions.h>
+#include <linux/root_dev.h>
+#include <linux/magic.h>
 #include <linux/err.h>
 
 /* Our partition linked list */
@@ -48,7 +50,7 @@ struct mtd_part {
  * the pointer to that structure with this macro.
  */
 #define PART(x)  ((struct mtd_part *)(x))
-
+#define IS_PART(mtd) (mtd->read == part_read)
 
 /*
  * MTD methods which simply translate the effective address and pass through
@@ -618,6 +620,153 @@ int mtd_del_partition(struct mtd_info *m
 }
 EXPORT_SYMBOL_GPL(mtd_del_partition);
 
+#ifdef CONFIG_MTD_ROOTFS_SPLIT
+#define ROOTFS_SPLIT_NAME "rootfs_data"
+#define ROOTFS_REMOVED_NAME "<removed>"
+
+struct squashfs_super_block {
+	__le32 s_magic;
+	__le32 pad0[9];
+	__le64 bytes_used;
+};
+
+
+static int split_squashfs(struct mtd_info *master, int offset, int *split_offset)
+{
+	struct squashfs_super_block sb;
+	int len, ret;
+
+	ret = master->read(master, offset, sizeof(sb), &len, (void *) &sb);
+	if (ret || (len != sizeof(sb))) {
+		printk(KERN_ALERT "split_squashfs: error occured while reading "
+			"from \"%s\"\n", master->name);
+		return -EINVAL;
+	}
+
+	if (SQUASHFS_MAGIC != le32_to_cpu(sb.s_magic) ) {
+		printk(KERN_ALERT "split_squashfs: no squashfs found in \"%s\"\n",
+			master->name);
+		*split_offset = 0;
+		return 0;
+	}
+
+	if (le64_to_cpu((sb.bytes_used)) <= 0) {
+		printk(KERN_ALERT "split_squashfs: squashfs is empty in \"%s\"\n",
+			master->name);
+		*split_offset = 0;
+		return 0;
+	}
+
+	len = (u32) le64_to_cpu(sb.bytes_used);
+	len += (offset & 0x000fffff);
+	len +=  (master->erasesize - 1);
+	len &= ~(master->erasesize - 1);
+	len -= (offset & 0x000fffff);
+	*split_offset = offset + len;
+
+	return 0;
+}
+
+static int split_rootfs_data(struct mtd_info *master, struct mtd_info *rpart, const struct mtd_partition *part)
+{
+	struct mtd_partition *dpart;
+	struct mtd_part *slave = NULL;
+	int ret, split_offset = 0;
+
+	ret = split_squashfs(master, part->offset, &split_offset);
+	if (ret)
+		return ret;
+
+	if (split_offset <= 0)
+		return 0;
+
+	dpart = kmalloc(sizeof(*part)+sizeof(ROOTFS_SPLIT_NAME)+1, GFP_KERNEL);
+	if (dpart == NULL) {
+		printk(KERN_INFO "split_squashfs: no memory for partition \"%s\"\n",
+			ROOTFS_SPLIT_NAME);
+		return -ENOMEM;
+	}
+
+	memcpy(dpart, part, sizeof(*part));
+	dpart->name = (unsigned char *)&dpart[1];
+	strcpy(dpart->name, ROOTFS_SPLIT_NAME);
+
+	dpart->size -= split_offset - dpart->offset;
+	dpart->offset = split_offset;
+
+	if (dpart == NULL)
+		return 1;
+
+	printk(KERN_INFO "mtd: partition \"%s\" created automatically, ofs=%llX, len=%llX \n",
+		ROOTFS_SPLIT_NAME, dpart->offset, dpart->size);
+
+	slave = allocate_partition(master, dpart, 0, split_offset);
+	if (IS_ERR(slave))
+		return PTR_ERR(slave);
+	mutex_lock(&mtd_partitions_mutex);
+	list_add(&slave->list, &mtd_partitions);
+	mutex_unlock(&mtd_partitions_mutex);
+
+	add_mtd_device(&slave->mtd);
+
+	rpart->split = &slave->mtd;
+
+	return 0;
+}
+
+static int refresh_rootfs_split(struct mtd_info *mtd)
+{
+	struct mtd_partition tpart;
+	struct mtd_part *part;
+	char *name;
+	//int index = 0;
+	int offset, size;
+	int ret;
+
+	part = PART(mtd);
+
+	/* check for the new squashfs offset first */
+	ret = split_squashfs(part->master, part->offset, &offset);
+	if (ret)
+		return ret;
+
+	if ((offset > 0) && !mtd->split) {
+		printk(KERN_INFO "%s: creating new split partition for \"%s\"\n", __func__, mtd->name);
+		/* if we don't have a rootfs split partition, create a new one */
+		tpart.name = (char *) mtd->name;
+		tpart.size = mtd->size;
+		tpart.offset = part->offset;
+
+		return split_rootfs_data(part->master, &part->mtd, &tpart);
+	} else if ((offset > 0) && mtd->split) {
+		/* update the offsets of the existing partition */
+		size = mtd->size + part->offset - offset;
+
+		part = PART(mtd->split);
+		part->offset = offset;
+		part->mtd.size = size;
+		printk(KERN_INFO "%s: %s partition \"" ROOTFS_SPLIT_NAME "\", offset: 0x%06x (0x%06x)\n",
+			__func__, (!strcmp(part->mtd.name, ROOTFS_SPLIT_NAME) ? "updating" : "creating"),
+			(u32) part->offset, (u32) part->mtd.size);
+		name = kmalloc(sizeof(ROOTFS_SPLIT_NAME) + 1, GFP_KERNEL);
+		strcpy(name, ROOTFS_SPLIT_NAME);
+		part->mtd.name = name;
+	} else if ((offset <= 0) && mtd->split) {
+		printk(KERN_INFO "%s: removing partition \"%s\"\n", __func__, mtd->split->name);
+
+		/* mark existing partition as removed */
+		part = PART(mtd->split);
+		name = kmalloc(sizeof(ROOTFS_SPLIT_NAME) + 1, GFP_KERNEL);
+		strcpy(name, ROOTFS_REMOVED_NAME);
+		part->mtd.name = name;
+		part->offset = 0;
+		part->mtd.size = 0;
+	}
+
+	return 0;
+}
+#endif /* CONFIG_MTD_ROOTFS_SPLIT */
+
 /*
  * This function, given a master MTD object and a partition table, creates
  * and registers slave MTD objects which are bound to the master according to
@@ -633,7 +782,7 @@ int add_mtd_partitions(struct mtd_info *
 {
 	struct mtd_part *slave;
 	uint64_t cur_offset = 0;
-	int i;
+	int i, ret;
 
 	printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
 
@@ -648,6 +797,21 @@ int add_mtd_partitions(struct mtd_info *
 
 		add_mtd_device(&slave->mtd);
 
+		if (!strcmp(parts[i].name, "rootfs")) {
+#ifdef CONFIG_MTD_ROOTFS_ROOT_DEV
+			if (ROOT_DEV == 0) {
+				printk(KERN_NOTICE "mtd: partition \"rootfs\" "
+					"set to be root filesystem\n");
+				ROOT_DEV = MKDEV(MTD_BLOCK_MAJOR, slave->mtd.index);
+			}
+#endif
+#ifdef CONFIG_MTD_ROOTFS_SPLIT
+			ret = split_rootfs_data(master, &slave->mtd, &parts[i]);
+			/* if (ret == 0)
+			 * 	j++; */
+#endif
+		}
+
 		cur_offset = slave->offset + slave->mtd.size;
 	}
 
@@ -655,6 +819,32 @@ int add_mtd_partitions(struct mtd_info *
 }
 EXPORT_SYMBOL(add_mtd_partitions);
 
+int refresh_mtd_partitions(struct mtd_info *mtd)
+{
+	int ret = 0;
+
+	if (IS_PART(mtd)) {
+		struct mtd_part *part;
+		struct mtd_info *master;
+
+		part = PART(mtd);
+		master = part->master;
+		if (master->refresh_device)
+			ret = master->refresh_device(master);
+	}
+
+	if (!ret && mtd->refresh_device)
+		ret = mtd->refresh_device(mtd);
+
+#ifdef CONFIG_MTD_ROOTFS_SPLIT
+	if (!ret && IS_PART(mtd) && !strcmp(mtd->name, "rootfs"))
+		refresh_rootfs_split(mtd);
+#endif
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(refresh_mtd_partitions);
+
 static DEFINE_SPINLOCK(part_parser_lock);
 static LIST_HEAD(part_parsers);
 
--- a/drivers/mtd/mtdchar.c
+++ b/drivers/mtd/mtdchar.c
@@ -841,6 +841,13 @@ static int mtd_ioctl(struct file *file, 
 		file->f_pos = 0;
 		break;
 	}
+#ifdef CONFIG_MTD_PARTITIONS
+	case MTDREFRESH:
+	{
+		ret = refresh_mtd_partitions(mtd);
+		break;
+	}
+#endif
 
 	case OTPGETREGIONCOUNT:
 	case OTPGETREGIONINFO:
--- a/include/linux/mtd/mtd.h
+++ b/include/linux/mtd/mtd.h
@@ -125,6 +125,7 @@ struct nand_ecclayout {
 	struct nand_oobfree oobfree[MTD_MAX_OOBFREE_ENTRIES_LARGE];
 };
 
+struct mtd_info;
 struct mtd_info {
 	u_char type;
 	uint32_t flags;
@@ -266,6 +267,9 @@ struct mtd_info {
 	struct device dev;
 	int usecount;
 
+	int (*refresh_device)(struct mtd_info *mtd);
+	struct mtd_info *split;
+
 	/* If the driver is something smart, like UBI, it may need to maintain
 	 * its own reference counting. The below functions are only for driver.
 	 * The driver may register its callbacks. These callbacks are not
--- a/include/linux/mtd/partitions.h
+++ b/include/linux/mtd/partitions.h
@@ -34,12 +34,14 @@
  * erasesize aligned (e.g. use MTDPART_OFS_NEXTBLK).
  */
 
+struct mtd_partition;
 struct mtd_partition {
 	char *name;			/* identifier string */
 	uint64_t size;			/* partition size */
 	uint64_t offset;		/* offset within the master MTD space */
 	uint32_t mask_flags;		/* master MTD flags to mask out for this partition */
 	struct nand_ecclayout *ecclayout;	/* out of band layout for this partition (NAND only) */
+	int (*refresh_partition)(struct mtd_info *);
 };
 
 #define MTDPART_OFS_NXTBLK	(-2)
@@ -51,6 +53,7 @@ struct mtd_info;
 
 int add_mtd_partitions(struct mtd_info *, const struct mtd_partition *, int);
 int del_mtd_partitions(struct mtd_info *);
+int refresh_mtd_partitions(struct mtd_info *);
 
 /*
  * Functions dealing with the various ways of partitioning the space
--- a/include/mtd/mtd-abi.h
+++ b/include/mtd/mtd-abi.h
@@ -127,6 +127,7 @@ struct otp_info {
 #define MEMWRITEOOB64		_IOWR('M', 21, struct mtd_oob_buf64)
 #define MEMREADOOB64		_IOWR('M', 22, struct mtd_oob_buf64)
 #define MEMISLOCKED		_IOR('M', 23, struct erase_info_user)
+#define MTDREFRESH		_IO('M', 23)
 
 /*
  * Obsolete legacy interface. Keep it in order not to break userspace