1 --- a/drivers/mtd/Kconfig
2 +++ b/drivers/mtd/Kconfig
3 @@ -33,6 +33,14 @@ config MTD_TESTS
4 should normally be compiled as kernel modules. The modules perform
5 various checks and verifications when loaded.
7 +config MTD_ROOTFS_ROOT_DEV
8 + bool "Automatically set 'rootfs' partition to be root filesystem"
11 +config MTD_ROOTFS_SPLIT
12 + bool "Automatically split 'rootfs' partition for squashfs"
15 config MTD_REDBOOT_PARTS
16 tristate "RedBoot partition table parsing"
18 --- a/drivers/mtd/mtdpart.c
19 +++ b/drivers/mtd/mtdpart.c
21 #include <linux/kmod.h>
22 #include <linux/mtd/mtd.h>
23 #include <linux/mtd/partitions.h>
24 +#include <linux/root_dev.h>
25 +#include <linux/magic.h>
26 #include <linux/err.h>
29 @@ -50,7 +52,7 @@ struct mtd_part {
30 * the pointer to that structure with this macro.
32 #define PART(x) ((struct mtd_part *)(x))
34 +#define IS_PART(mtd) (mtd->read == part_read)
37 * MTD methods which simply translate the effective address and pass through
38 @@ -637,6 +639,155 @@ int mtd_del_partition(struct mtd_info *m
40 EXPORT_SYMBOL_GPL(mtd_del_partition);
42 +#ifdef CONFIG_MTD_ROOTFS_SPLIT
43 +#define ROOTFS_SPLIT_NAME "rootfs_data"
44 +#define ROOTFS_REMOVED_NAME "<removed>"
46 +struct squashfs_super_block {
53 +static int split_squashfs(struct mtd_info *master, int offset, int *split_offset)
55 + struct squashfs_super_block sb;
58 + ret = master->read(master, offset, sizeof(sb), &len, (void *) &sb);
59 + if (ret || (len != sizeof(sb))) {
60 + printk(KERN_ALERT "split_squashfs: error occured while reading "
61 + "from \"%s\"\n", master->name);
65 + if (SQUASHFS_MAGIC != le32_to_cpu(sb.s_magic) ) {
66 + printk(KERN_ALERT "split_squashfs: no squashfs found in \"%s\"\n",
72 + if (le64_to_cpu((sb.bytes_used)) <= 0) {
73 + printk(KERN_ALERT "split_squashfs: squashfs is empty in \"%s\"\n",
79 + len = (u32) le64_to_cpu(sb.bytes_used);
80 + len += (offset & 0x000fffff);
81 + len += (master->erasesize - 1);
82 + len &= ~(master->erasesize - 1);
83 + len -= (offset & 0x000fffff);
84 + *split_offset = offset + len;
89 +static int split_rootfs_data(struct mtd_info *master, struct mtd_info *rpart, const struct mtd_partition *part)
91 + struct mtd_partition *dpart;
92 + struct mtd_part *slave = NULL;
93 + struct mtd_part *spart;
94 + int ret, split_offset = 0;
96 + spart = PART(rpart);
97 + ret = split_squashfs(master, spart->offset, &split_offset);
101 + if (split_offset <= 0)
104 + dpart = kmalloc(sizeof(*part)+sizeof(ROOTFS_SPLIT_NAME)+1, GFP_KERNEL);
105 + if (dpart == NULL) {
106 + printk(KERN_INFO "split_squashfs: no memory for partition \"%s\"\n",
107 + ROOTFS_SPLIT_NAME);
111 + memcpy(dpart, part, sizeof(*part));
112 + dpart->name = (unsigned char *)&dpart[1];
113 + strcpy(dpart->name, ROOTFS_SPLIT_NAME);
115 + dpart->size = rpart->size - (split_offset - spart->offset);
116 + dpart->offset = split_offset;
121 + printk(KERN_INFO "mtd: partition \"%s\" created automatically, ofs=%llX, len=%llX \n",
122 + ROOTFS_SPLIT_NAME, dpart->offset, dpart->size);
124 + slave = allocate_partition(master, dpart, 0, split_offset);
126 + return PTR_ERR(slave);
127 + mutex_lock(&mtd_partitions_mutex);
128 + list_add(&slave->list, &mtd_partitions);
129 + mutex_unlock(&mtd_partitions_mutex);
131 + add_mtd_device(&slave->mtd);
133 + rpart->split = &slave->mtd;
138 +static int refresh_rootfs_split(struct mtd_info *mtd)
140 + struct mtd_partition tpart;
141 + struct mtd_part *part;
149 + /* check for the new squashfs offset first */
150 + ret = split_squashfs(part->master, part->offset, &offset);
154 + if ((offset > 0) && !mtd->split) {
155 + printk(KERN_INFO "%s: creating new split partition for \"%s\"\n", __func__, mtd->name);
156 + /* if we don't have a rootfs split partition, create a new one */
157 + tpart.name = (char *) mtd->name;
158 + tpart.size = mtd->size;
159 + tpart.offset = part->offset;
161 + return split_rootfs_data(part->master, &part->mtd, &tpart);
162 + } else if ((offset > 0) && mtd->split) {
163 + /* update the offsets of the existing partition */
164 + size = mtd->size + part->offset - offset;
166 + part = PART(mtd->split);
167 + part->offset = offset;
168 + part->mtd.size = size;
169 + printk(KERN_INFO "%s: %s partition \"" ROOTFS_SPLIT_NAME "\", offset: 0x%06x (0x%06x)\n",
170 + __func__, (!strcmp(part->mtd.name, ROOTFS_SPLIT_NAME) ? "updating" : "creating"),
171 + (u32) part->offset, (u32) part->mtd.size);
172 + name = kmalloc(sizeof(ROOTFS_SPLIT_NAME) + 1, GFP_KERNEL);
173 + strcpy(name, ROOTFS_SPLIT_NAME);
174 + part->mtd.name = name;
175 + } else if ((offset <= 0) && mtd->split) {
176 + printk(KERN_INFO "%s: removing partition \"%s\"\n", __func__, mtd->split->name);
178 + /* mark existing partition as removed */
179 + part = PART(mtd->split);
180 + name = kmalloc(sizeof(ROOTFS_SPLIT_NAME) + 1, GFP_KERNEL);
181 + strcpy(name, ROOTFS_REMOVED_NAME);
182 + part->mtd.name = name;
184 + part->mtd.size = 0;
189 +#endif /* CONFIG_MTD_ROOTFS_SPLIT */
192 * This function, given a master MTD object and a partition table, creates
193 * and registers slave MTD objects which are bound to the master according to
194 @@ -653,6 +804,9 @@ int add_mtd_partitions(struct mtd_info *
195 struct mtd_part *slave;
196 uint64_t cur_offset = 0;
198 +#ifdef CONFIG_MTD_ROOTFS_SPLIT
202 printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
204 @@ -667,12 +821,53 @@ int add_mtd_partitions(struct mtd_info *
206 add_mtd_device(&slave->mtd);
208 + if (!strcmp(parts[i].name, "rootfs")) {
209 +#ifdef CONFIG_MTD_ROOTFS_ROOT_DEV
210 + if (ROOT_DEV == 0) {
211 + printk(KERN_NOTICE "mtd: partition \"rootfs\" "
212 + "set to be root filesystem\n");
213 + ROOT_DEV = MKDEV(MTD_BLOCK_MAJOR, slave->mtd.index);
216 +#ifdef CONFIG_MTD_ROOTFS_SPLIT
217 + ret = split_rootfs_data(master, &slave->mtd, &parts[i]);
223 cur_offset = slave->offset + slave->mtd.size;
229 +int mtd_device_refresh(struct mtd_info *mtd)
233 + if (IS_PART(mtd)) {
234 + struct mtd_part *part;
235 + struct mtd_info *master;
238 + master = part->master;
239 + if (master->refresh_device)
240 + ret = master->refresh_device(master);
243 + if (!ret && mtd->refresh_device)
244 + ret = mtd->refresh_device(mtd);
246 +#ifdef CONFIG_MTD_ROOTFS_SPLIT
247 + if (!ret && IS_PART(mtd) && !strcmp(mtd->name, "rootfs"))
248 + refresh_rootfs_split(mtd);
253 +EXPORT_SYMBOL_GPL(mtd_device_refresh);
255 static DEFINE_SPINLOCK(part_parser_lock);
256 static LIST_HEAD(part_parsers);
258 --- a/drivers/mtd/mtdchar.c
259 +++ b/drivers/mtd/mtdchar.c
260 @@ -948,6 +948,12 @@ static int mtd_ioctl(struct file *file,
266 + ret = mtd_device_refresh(mtd);
273 --- a/include/linux/mtd/mtd.h
274 +++ b/include/linux/mtd/mtd.h
275 @@ -125,6 +125,7 @@ struct nand_ecclayout {
276 struct nand_oobfree oobfree[MTD_MAX_OOBFREE_ENTRIES_LARGE];
283 @@ -277,6 +278,9 @@ struct mtd_info {
287 + int (*refresh_device)(struct mtd_info *mtd);
288 + struct mtd_info *split;
290 /* If the driver is something smart, like UBI, it may need to maintain
291 * its own reference counting. The below functions are only for driver.
292 * The driver may register its callbacks. These callbacks are not
293 @@ -327,6 +331,7 @@ struct mtd_partition;
294 extern int mtd_device_register(struct mtd_info *master,
295 const struct mtd_partition *parts,
297 +extern int mtd_device_refresh(struct mtd_info *master);
298 extern int mtd_device_unregister(struct mtd_info *master);
299 extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
300 extern int __get_mtd_device(struct mtd_info *mtd);
301 --- a/include/linux/mtd/partitions.h
302 +++ b/include/linux/mtd/partitions.h
304 * erasesize aligned (e.g. use MTDPART_OFS_NEXTBLK).
307 +struct mtd_partition;
308 struct mtd_partition {
309 char *name; /* identifier string */
310 uint64_t size; /* partition size */
311 uint64_t offset; /* offset within the master MTD space */
312 uint32_t mask_flags; /* master MTD flags to mask out for this partition */
313 struct nand_ecclayout *ecclayout; /* out of band layout for this partition (NAND only) */
314 + int (*refresh_partition)(struct mtd_info *);
317 #define MTDPART_OFS_NXTBLK (-2)
318 --- a/include/mtd/mtd-abi.h
319 +++ b/include/mtd/mtd-abi.h
320 @@ -127,6 +127,7 @@ struct otp_info {
321 #define MEMWRITEOOB64 _IOWR('M', 21, struct mtd_oob_buf64)
322 #define MEMREADOOB64 _IOWR('M', 22, struct mtd_oob_buf64)
323 #define MEMISLOCKED _IOR('M', 23, struct erase_info_user)
324 +#define MTDREFRESH _IO('M', 24)
327 * Obsolete legacy interface. Keep it in order not to break userspace