Root/target/linux/generic/patches-2.6.39/400-rootfs_split.patch

1--- a/drivers/mtd/Kconfig
2+++ b/drivers/mtd/Kconfig
3@@ -47,6 +47,16 @@ config MTD_PARTITIONS
4 
5 if MTD_PARTITIONS
6 
7+config MTD_ROOTFS_ROOT_DEV
8+ bool "Automatically set 'rootfs' partition to be root filesystem"
9+ depends on MTD_PARTITIONS
10+ default y
11+
12+config MTD_ROOTFS_SPLIT
13+ bool "Automatically split 'rootfs' partition for squashfs"
14+ depends on MTD_PARTITIONS
15+ default y
16+
17 config MTD_REDBOOT_PARTS
18     tristate "RedBoot partition table parsing"
19     ---help---
20--- a/drivers/mtd/mtdpart.c
21+++ b/drivers/mtd/mtdpart.c
22@@ -29,6 +29,8 @@
23 #include <linux/kmod.h>
24 #include <linux/mtd/mtd.h>
25 #include <linux/mtd/partitions.h>
26+#include <linux/root_dev.h>
27+#include <linux/magic.h>
28 #include <linux/err.h>
29 
30 /* Our partition linked list */
31@@ -48,7 +50,7 @@ struct mtd_part {
32  * the pointer to that structure with this macro.
33  */
34 #define PART(x) ((struct mtd_part *)(x))
35-
36+#define IS_PART(mtd) (mtd->read == part_read)
37 
38 /*
39  * MTD methods which simply translate the effective address and pass through
40@@ -636,6 +638,155 @@ int mtd_del_partition(struct mtd_info *m
41 }
42 EXPORT_SYMBOL_GPL(mtd_del_partition);
43 
44+#ifdef CONFIG_MTD_ROOTFS_SPLIT
45+#define ROOTFS_SPLIT_NAME "rootfs_data"
46+#define ROOTFS_REMOVED_NAME "<removed>"
47+
48+struct squashfs_super_block {
49+ __le32 s_magic;
50+ __le32 pad0[9];
51+ __le64 bytes_used;
52+};
53+
54+
55+static int split_squashfs(struct mtd_info *master, int offset, int *split_offset)
56+{
57+ struct squashfs_super_block sb;
58+ int len, ret;
59+
60+ ret = master->read(master, offset, sizeof(sb), &len, (void *) &sb);
61+ if (ret || (len != sizeof(sb))) {
62+ printk(KERN_ALERT "split_squashfs: error occured while reading "
63+ "from \"%s\"\n", master->name);
64+ return -EINVAL;
65+ }
66+
67+ if (SQUASHFS_MAGIC != le32_to_cpu(sb.s_magic) ) {
68+ printk(KERN_ALERT "split_squashfs: no squashfs found in \"%s\"\n",
69+ master->name);
70+ *split_offset = 0;
71+ return 0;
72+ }
73+
74+ if (le64_to_cpu((sb.bytes_used)) <= 0) {
75+ printk(KERN_ALERT "split_squashfs: squashfs is empty in \"%s\"\n",
76+ master->name);
77+ *split_offset = 0;
78+ return 0;
79+ }
80+
81+ len = (u32) le64_to_cpu(sb.bytes_used);
82+ len += (offset & 0x000fffff);
83+ len += (master->erasesize - 1);
84+ len &= ~(master->erasesize - 1);
85+ len -= (offset & 0x000fffff);
86+ *split_offset = offset + len;
87+
88+ return 0;
89+}
90+
91+static int split_rootfs_data(struct mtd_info *master, struct mtd_info *rpart, const struct mtd_partition *part)
92+{
93+ struct mtd_partition *dpart;
94+ struct mtd_part *slave = NULL;
95+ struct mtd_part *spart;
96+ int ret, split_offset = 0;
97+
98+ spart = PART(rpart);
99+ ret = split_squashfs(master, spart->offset, &split_offset);
100+ if (ret)
101+ return ret;
102+
103+ if (split_offset <= 0)
104+ return 0;
105+
106+ dpart = kmalloc(sizeof(*part)+sizeof(ROOTFS_SPLIT_NAME)+1, GFP_KERNEL);
107+ if (dpart == NULL) {
108+ printk(KERN_INFO "split_squashfs: no memory for partition \"%s\"\n",
109+ ROOTFS_SPLIT_NAME);
110+ return -ENOMEM;
111+ }
112+
113+ memcpy(dpart, part, sizeof(*part));
114+ dpart->name = (unsigned char *)&dpart[1];
115+ strcpy(dpart->name, ROOTFS_SPLIT_NAME);
116+
117+ dpart->size = rpart->size - (split_offset - spart->offset);
118+ dpart->offset = split_offset;
119+
120+ if (dpart == NULL)
121+ return 1;
122+
123+ printk(KERN_INFO "mtd: partition \"%s\" created automatically, ofs=%llX, len=%llX \n",
124+ ROOTFS_SPLIT_NAME, dpart->offset, dpart->size);
125+
126+ slave = allocate_partition(master, dpart, 0, split_offset);
127+ if (IS_ERR(slave))
128+ return PTR_ERR(slave);
129+ mutex_lock(&mtd_partitions_mutex);
130+ list_add(&slave->list, &mtd_partitions);
131+ mutex_unlock(&mtd_partitions_mutex);
132+
133+ add_mtd_device(&slave->mtd);
134+
135+ rpart->split = &slave->mtd;
136+
137+ return 0;
138+}
139+
140+static int refresh_rootfs_split(struct mtd_info *mtd)
141+{
142+ struct mtd_partition tpart;
143+ struct mtd_part *part;
144+ char *name;
145+ //int index = 0;
146+ int offset, size;
147+ int ret;
148+
149+ part = PART(mtd);
150+
151+ /* check for the new squashfs offset first */
152+ ret = split_squashfs(part->master, part->offset, &offset);
153+ if (ret)
154+ return ret;
155+
156+ if ((offset > 0) && !mtd->split) {
157+ printk(KERN_INFO "%s: creating new split partition for \"%s\"\n", __func__, mtd->name);
158+ /* if we don't have a rootfs split partition, create a new one */
159+ tpart.name = (char *) mtd->name;
160+ tpart.size = mtd->size;
161+ tpart.offset = part->offset;
162+
163+ return split_rootfs_data(part->master, &part->mtd, &tpart);
164+ } else if ((offset > 0) && mtd->split) {
165+ /* update the offsets of the existing partition */
166+ size = mtd->size + part->offset - offset;
167+
168+ part = PART(mtd->split);
169+ part->offset = offset;
170+ part->mtd.size = size;
171+ printk(KERN_INFO "%s: %s partition \"" ROOTFS_SPLIT_NAME "\", offset: 0x%06x (0x%06x)\n",
172+ __func__, (!strcmp(part->mtd.name, ROOTFS_SPLIT_NAME) ? "updating" : "creating"),
173+ (u32) part->offset, (u32) part->mtd.size);
174+ name = kmalloc(sizeof(ROOTFS_SPLIT_NAME) + 1, GFP_KERNEL);
175+ strcpy(name, ROOTFS_SPLIT_NAME);
176+ part->mtd.name = name;
177+ } else if ((offset <= 0) && mtd->split) {
178+ printk(KERN_INFO "%s: removing partition \"%s\"\n", __func__, mtd->split->name);
179+
180+ /* mark existing partition as removed */
181+ part = PART(mtd->split);
182+ name = kmalloc(sizeof(ROOTFS_SPLIT_NAME) + 1, GFP_KERNEL);
183+ strcpy(name, ROOTFS_REMOVED_NAME);
184+ part->mtd.name = name;
185+ part->offset = 0;
186+ part->mtd.size = 0;
187+ }
188+
189+ return 0;
190+}
191+#endif /* CONFIG_MTD_ROOTFS_SPLIT */
192+
193 /*
194  * This function, given a master MTD object and a partition table, creates
195  * and registers slave MTD objects which are bound to the master according to
196@@ -652,6 +803,9 @@ int add_mtd_partitions(struct mtd_info *
197     struct mtd_part *slave;
198     uint64_t cur_offset = 0;
199     int i;
200+#ifdef CONFIG_MTD_ROOTFS_SPLIT
201+ int ret;
202+#endif
203 
204     printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
205 
206@@ -666,6 +820,21 @@ int add_mtd_partitions(struct mtd_info *
207 
208         add_mtd_device(&slave->mtd);
209 
210+ if (!strcmp(parts[i].name, "rootfs")) {
211+#ifdef CONFIG_MTD_ROOTFS_ROOT_DEV
212+ if (ROOT_DEV == 0) {
213+ printk(KERN_NOTICE "mtd: partition \"rootfs\" "
214+ "set to be root filesystem\n");
215+ ROOT_DEV = MKDEV(MTD_BLOCK_MAJOR, slave->mtd.index);
216+ }
217+#endif
218+#ifdef CONFIG_MTD_ROOTFS_SPLIT
219+ ret = split_rootfs_data(master, &slave->mtd, &parts[i]);
220+ /* if (ret == 0)
221+ * j++; */
222+#endif
223+ }
224+
225         cur_offset = slave->offset + slave->mtd.size;
226     }
227 
228@@ -673,6 +842,32 @@ int add_mtd_partitions(struct mtd_info *
229 }
230 EXPORT_SYMBOL(add_mtd_partitions);
231 
232+int refresh_mtd_partitions(struct mtd_info *mtd)
233+{
234+ int ret = 0;
235+
236+ if (IS_PART(mtd)) {
237+ struct mtd_part *part;
238+ struct mtd_info *master;
239+
240+ part = PART(mtd);
241+ master = part->master;
242+ if (master->refresh_device)
243+ ret = master->refresh_device(master);
244+ }
245+
246+ if (!ret && mtd->refresh_device)
247+ ret = mtd->refresh_device(mtd);
248+
249+#ifdef CONFIG_MTD_ROOTFS_SPLIT
250+ if (!ret && IS_PART(mtd) && !strcmp(mtd->name, "rootfs"))
251+ refresh_rootfs_split(mtd);
252+#endif
253+
254+ return 0;
255+}
256+EXPORT_SYMBOL_GPL(refresh_mtd_partitions);
257+
258 static DEFINE_SPINLOCK(part_parser_lock);
259 static LIST_HEAD(part_parsers);
260 
261--- a/drivers/mtd/mtdchar.c
262+++ b/drivers/mtd/mtdchar.c
263@@ -841,6 +841,13 @@ static int mtd_ioctl(struct file *file,
264         file->f_pos = 0;
265         break;
266     }
267+#ifdef CONFIG_MTD_PARTITIONS
268+ case MTDREFRESH:
269+ {
270+ ret = refresh_mtd_partitions(mtd);
271+ break;
272+ }
273+#endif
274 
275     case OTPGETREGIONCOUNT:
276     case OTPGETREGIONINFO:
277--- a/include/linux/mtd/mtd.h
278+++ b/include/linux/mtd/mtd.h
279@@ -125,6 +125,7 @@ struct nand_ecclayout {
280     struct nand_oobfree oobfree[MTD_MAX_OOBFREE_ENTRIES_LARGE];
281 };
282 
283+struct mtd_info;
284 struct mtd_info {
285     u_char type;
286     uint32_t flags;
287@@ -277,6 +278,9 @@ struct mtd_info {
288     struct device dev;
289     int usecount;
290 
291+ int (*refresh_device)(struct mtd_info *mtd);
292+ struct mtd_info *split;
293+
294     /* If the driver is something smart, like UBI, it may need to maintain
295      * its own reference counting. The below functions are only for driver.
296      * The driver may register its callbacks. These callbacks are not
297--- a/include/linux/mtd/partitions.h
298+++ b/include/linux/mtd/partitions.h
299@@ -34,12 +34,14 @@
300  * erasesize aligned (e.g. use MTDPART_OFS_NEXTBLK).
301  */
302 
303+struct mtd_partition;
304 struct mtd_partition {
305     char *name; /* identifier string */
306     uint64_t size; /* partition size */
307     uint64_t offset; /* offset within the master MTD space */
308     uint32_t mask_flags; /* master MTD flags to mask out for this partition */
309     struct nand_ecclayout *ecclayout; /* out of band layout for this partition (NAND only) */
310+ int (*refresh_partition)(struct mtd_info *);
311 };
312 
313 #define MTDPART_OFS_NXTBLK (-2)
314@@ -51,6 +53,7 @@ struct mtd_info;
315 
316 int add_mtd_partitions(struct mtd_info *, const struct mtd_partition *, int);
317 int del_mtd_partitions(struct mtd_info *);
318+int refresh_mtd_partitions(struct mtd_info *);
319 
320 /*
321  * Functions dealing with the various ways of partitioning the space
322--- a/include/mtd/mtd-abi.h
323+++ b/include/mtd/mtd-abi.h
324@@ -127,6 +127,7 @@ struct otp_info {
325 #define MEMWRITEOOB64 _IOWR('M', 21, struct mtd_oob_buf64)
326 #define MEMREADOOB64 _IOWR('M', 22, struct mtd_oob_buf64)
327 #define MEMISLOCKED _IOR('M', 23, struct erase_info_user)
328+#define MTDREFRESH _IO('M', 23)
329 
330 /*
331  * Obsolete legacy interface. Keep it in order not to break userspace
332

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