--- a/drivers/mtd/Kconfig +++ b/drivers/mtd/Kconfig @@ -52,6 +52,14 @@ config MTD_TESTS WARNING: some of the tests will ERASE entire MTD device which they test. Do not use these tests unless you really know what you do. +config MTD_ROOTFS_ROOT_DEV + bool "Automatically set 'rootfs' partition to be root filesystem" + default y + +config MTD_ROOTFS_SPLIT + bool "Automatically split 'rootfs' partition for squashfs" + default y + config MTD_REDBOOT_PARTS tristate "RedBoot partition table parsing" ---help--- --- a/drivers/mtd/mtdpart.c +++ b/drivers/mtd/mtdpart.c @@ -30,6 +30,8 @@ #include <linux/mtd/mtd.h> #include <linux/mtd/partitions.h> #include <linux/of.h> +#include <linux/root_dev.h> +#include <linux/magic.h> #include <linux/err.h> #include "mtdcore.h" @@ -53,7 +55,7 @@ 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 @@ -706,6 +708,144 @@ 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 = mtd_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; + struct mtd_part *spart; + int ret, split_offset = 0; + + spart = PART(rpart); + ret = split_squashfs(master, spart->offset, &split_offset); + if (ret) + return ret; + + if (split_offset <= 0) + return 0; + + memcpy(&dpart, part, sizeof(dpart)); + dpart.name = ROOTFS_SPLIT_NAME; + + dpart.size = rpart->size - (split_offset - spart->offset); + dpart.offset = split_offset; + + 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 @@ -722,6 +862,9 @@ int add_mtd_partitions(struct mtd_info * struct mtd_part *slave; uint64_t cur_offset = 0; int i; +#ifdef CONFIG_MTD_ROOTFS_SPLIT + int ret; +#endif printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name); @@ -736,12 +879,53 @@ 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; } return 0; } +int mtd_device_refresh(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(mtd_device_refresh); + static DEFINE_SPINLOCK(part_parser_lock); static LIST_HEAD(part_parsers); --- a/drivers/mtd/mtdchar.c +++ b/drivers/mtd/mtdchar.c @@ -1008,6 +1008,12 @@ static int mtdchar_ioctl(struct file *fi break; } + case MTDREFRESH: + { + ret = mtd_device_refresh(mtd); + break; + } + default: ret = -ENOTTY; } --- a/include/linux/mtd/mtd.h +++ b/include/linux/mtd/mtd.h @@ -115,6 +115,7 @@ struct nand_ecclayout { struct module; /* only needed for owner field in mtd_info */ +struct mtd_info; struct mtd_info { u_char type; uint32_t flags; @@ -231,6 +232,9 @@ struct mtd_info { int (*_block_markbad) (struct mtd_info *mtd, loff_t ofs); int (*_suspend) (struct mtd_info *mtd); void (*_resume) (struct mtd_info *mtd); + 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. @@ -397,6 +401,7 @@ extern int mtd_device_parse_register(str int defnr_parts); #define mtd_device_register(master, parts, nr_parts) \ mtd_device_parse_register(master, NULL, NULL, parts, nr_parts) +extern int mtd_device_refresh(struct mtd_info *master); extern int mtd_device_unregister(struct mtd_info *master); extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num); extern int __get_mtd_device(struct mtd_info *mtd); --- a/include/linux/mtd/partitions.h +++ b/include/linux/mtd/partitions.h @@ -37,12 +37,14 @@ */ struct mtd_info; +struct mtd_partition; struct mtd_partition { const 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_RETAIN (-3) --- a/include/uapi/mtd/mtd-abi.h +++ b/include/uapi/mtd/mtd-abi.h @@ -203,6 +203,7 @@ struct otp_info { * without OOB, e.g., NOR flash. */ #define MEMWRITE _IOWR('M', 24, struct mtd_write_req) +#define MTDREFRESH _IO('M', 50) /* * Obsolete legacy interface. Keep it in order not to break userspace