--- /dev/null
+--- a/drivers/mtd/Kconfig
++++ b/drivers/mtd/Kconfig
+@@ -53,6 +53,16 @@ config MTD_TESTS
+ should normally be compiled as kernel modules. The modules perform
+ various checks and verifications when loaded.
+
++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
+@@ -18,6 +18,8 @@
+ #include <linux/mtd/mtd.h>
+ #include <linux/mtd/partitions.h>
+ #include <linux/mtd/compatmac.h>
++#include <linux/root_dev.h>
++#include <linux/magic.h>
+
+ /* Our partition linked list */
+ static LIST_HEAD(mtd_partitions);
+@@ -35,7 +37,7 @@ 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
+@@ -502,6 +504,150 @@ out_register:
+ return slave;
+ }
+
++#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 split_offset = 0;
++ int ret;
++
++ 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 = add_one_partition(master, dpart, 0, split_offset);
++ if (!slave) {
++ kfree(dpart);
++ return -ENOMEM;
++ }
++ 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
+@@ -517,7 +663,7 @@ 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);
+
+@@ -525,6 +671,21 @@ int add_mtd_partitions(struct mtd_info *
+ slave = add_one_partition(master, parts + i, i, cur_offset);
+ if (!slave)
+ return -ENOMEM;
++
++ 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;
+ }
+
+@@ -532,6 +693,32 @@ 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/devices/block2mtd.c
++++ b/drivers/mtd/devices/block2mtd.c
+@@ -29,6 +29,8 @@ struct block2mtd_dev {
+ struct block_device *blkdev;
+ struct mtd_info mtd;
+ struct mutex write_mutex;
++ rwlock_t bdev_mutex;
++ char devname[0];
+ };
+
+
+@@ -81,6 +83,12 @@ static int block2mtd_erase(struct mtd_in
+ size_t len = instr->len;
+ int err;
+
++ read_lock(&dev->bdev_mutex);
++ if (!dev->blkdev) {
++ err = -EINVAL;
++ goto done;
++ }
++
+ instr->state = MTD_ERASING;
+ mutex_lock(&dev->write_mutex);
+ err = _block2mtd_erase(dev, from, len);
+@@ -93,6 +101,10 @@ static int block2mtd_erase(struct mtd_in
+
+ instr->state = MTD_ERASE_DONE;
+ mtd_erase_callback(instr);
++
++done:
++ read_unlock(&dev->bdev_mutex);
++
+ return err;
+ }
+
+@@ -104,10 +116,14 @@ static int block2mtd_read(struct mtd_inf
+ struct page *page;
+ int index = from >> PAGE_SHIFT;
+ int offset = from & (PAGE_SIZE-1);
+- int cpylen;
++ int cpylen, err = 0;
++
++ read_lock(&dev->bdev_mutex);
++ if (!dev->blkdev || (from > mtd->size)) {
++ err = -EINVAL;
++ goto done;
++ }
+
+- if (from > mtd->size)
+- return -EINVAL;
+ if (from + len > mtd->size)
+ len = mtd->size - from;
+
+@@ -122,10 +138,14 @@ static int block2mtd_read(struct mtd_inf
+ len = len - cpylen;
+
+ page = page_read(dev->blkdev->bd_inode->i_mapping, index);
+- if (!page)
+- return -ENOMEM;
+- if (IS_ERR(page))
+- return PTR_ERR(page);
++ if (!page) {
++ err = -ENOMEM;
++ goto done;
++ }
++ if (IS_ERR(page)) {
++ err = PTR_ERR(page);
++ goto done;
++ }
+
+ memcpy(buf, page_address(page) + offset, cpylen);
+ page_cache_release(page);
+@@ -136,7 +156,10 @@ static int block2mtd_read(struct mtd_inf
+ offset = 0;
+ index++;
+ }
+- return 0;
++
++done:
++ read_unlock(&dev->bdev_mutex);
++ return err;
+ }
+
+
+@@ -188,12 +211,22 @@ static int block2mtd_write(struct mtd_in
+ size_t *retlen, const u_char *buf)
+ {
+ struct block2mtd_dev *dev = mtd->priv;
+- int err;
++ int err = 0;
++
++ read_lock(&dev->bdev_mutex);
++ if (!dev->blkdev) {
++ err = -EINVAL;
++ goto done;
++ }
+
+ if (!len)
+- return 0;
+- if (to >= mtd->size)
+- return -ENOSPC;
++ goto done;
++
++ if (to >= mtd->size) {
++ err = -ENOSPC;
++ goto done;
++ }
++
+ if (to + len > mtd->size)
+ len = mtd->size - to;
+
+@@ -202,6 +235,9 @@ static int block2mtd_write(struct mtd_in
+ mutex_unlock(&dev->write_mutex);
+ if (err > 0)
+ err = 0;
++
++done:
++ read_unlock(&dev->bdev_mutex);
+ return err;
+ }
+
+@@ -210,52 +246,29 @@ static int block2mtd_write(struct mtd_in
+ static void block2mtd_sync(struct mtd_info *mtd)
+ {
+ struct block2mtd_dev *dev = mtd->priv;
+- sync_blockdev(dev->blkdev);
+- return;
+-}
+-
+-
+-static void block2mtd_free_device(struct block2mtd_dev *dev)
+-{
+- if (!dev)
+- return;
+-
+- kfree(dev->mtd.name);
+
+- if (dev->blkdev) {
+- invalidate_mapping_pages(dev->blkdev->bd_inode->i_mapping,
+- 0, -1);
+- close_bdev_exclusive(dev->blkdev, FMODE_READ|FMODE_WRITE);
+- }
++ read_lock(&dev->bdev_mutex);
++ if (dev->blkdev)
++ sync_blockdev(dev->blkdev);
++ read_unlock(&dev->bdev_mutex);
+
+- kfree(dev);
++ return;
+ }
+
+
+-/* FIXME: ensure that mtd->size % erase_size == 0 */
+-static struct block2mtd_dev *add_device(char *devname, int erase_size, const char *mtdname)
++static int _open_bdev(struct block2mtd_dev *dev)
+ {
+ struct block_device *bdev;
+- struct block2mtd_dev *dev;
+- struct mtd_partition *part;
+- char *name;
+-
+- if (!devname)
+- return NULL;
+-
+- dev = kzalloc(sizeof(struct block2mtd_dev), GFP_KERNEL);
+- if (!dev)
+- return NULL;
+
+ /* Get a handle on the device */
+- bdev = open_bdev_exclusive(devname, FMODE_READ|FMODE_WRITE, NULL);
++ bdev = open_bdev_exclusive(dev->devname, FMODE_READ|FMODE_WRITE, NULL);
+ #ifndef MODULE
+ if (IS_ERR(bdev)) {
+
+ /* We might not have rootfs mounted at this point. Try
+ to resolve the device name by other means. */
+
+- dev_t devt = name_to_dev_t(devname);
++ dev_t devt = name_to_dev_t(dev->devname);
+ if (devt) {
+ bdev = open_by_devnum(devt, FMODE_WRITE | FMODE_READ);
+ }
+@@ -263,17 +276,98 @@ static struct block2mtd_dev *add_device(
+ #endif
+
+ if (IS_ERR(bdev)) {
+- ERROR("error: cannot open device %s", devname);
+- goto devinit_err;
++ ERROR("error: cannot open device %s", dev->devname);
++ return 1;
+ }
+ dev->blkdev = bdev;
+
+ if (MAJOR(bdev->bd_dev) == MTD_BLOCK_MAJOR) {
+ ERROR("attempting to use an MTD device as a block device");
+- goto devinit_err;
++ return 1;
+ }
+
++ return 0;
++}
++
++static void _close_bdev(struct block2mtd_dev *dev)
++{
++ struct block_device *bdev;
++
++ if (!dev->blkdev)
++ return;
++
++ bdev = dev->blkdev;
++ invalidate_mapping_pages(dev->blkdev->bd_inode->i_mapping, 0, -1);
++ close_bdev_exclusive(dev->blkdev, FMODE_READ|FMODE_WRITE);
++ dev->blkdev = NULL;
++}
++
++static void block2mtd_free_device(struct block2mtd_dev *dev)
++{
++ if (!dev)
++ return;
++
++ kfree(dev->mtd.name);
++ _close_bdev(dev);
++ kfree(dev);
++}
++
++
++static int block2mtd_refresh(struct mtd_info *mtd)
++{
++ struct block2mtd_dev *dev = mtd->priv;
++ struct block_device *bdev;
++ dev_t devt;
++ int err = 0;
++
++ /* no other mtd function can run at this point */
++ write_lock(&dev->bdev_mutex);
++
++ /* get the device number for the whole disk */
++ devt = MKDEV(MAJOR(dev->blkdev->bd_dev), 0);
++
++ /* close the old block device */
++ _close_bdev(dev);
++
++ /* open the whole disk, issue a partition rescan, then */
++ bdev = open_by_devnum(devt, FMODE_WRITE | FMODE_READ);
++ if (!bdev || !bdev->bd_disk)
++ err = -EINVAL;
++#ifndef CONFIG_MTD_BLOCK2MTD_MODULE
++ else
++ err = rescan_partitions(bdev->bd_disk, bdev);
++#endif
++ if (bdev)
++ close_bdev_exclusive(bdev, FMODE_READ|FMODE_WRITE);
++
++ /* try to open the partition block device again */
++ _open_bdev(dev);
++ write_unlock(&dev->bdev_mutex);
++
++ return err;
++}
++
++/* FIXME: ensure that mtd->size % erase_size == 0 */
++static struct block2mtd_dev *add_device(char *devname, int erase_size, char *mtdname)
++{
++ struct block2mtd_dev *dev;
++ struct mtd_partition *part;
++ char *name;
++
++ if (!devname)
++ return NULL;
++
++ dev = kzalloc(sizeof(struct block2mtd_dev) + strlen(devname) + 1, GFP_KERNEL);
++ if (!dev)
++ return NULL;
++
++ strcpy(dev->devname, devname);
++
++ if (_open_bdev(dev))
++ goto devinit_err;
++
+ mutex_init(&dev->write_mutex);
++ rwlock_init(&dev->bdev_mutex);
+
+ if (!mtdname)
+ mtdname = devname;
+@@ -297,6 +391,7 @@ static struct block2mtd_dev *add_device(
+ dev->mtd.read = block2mtd_read;
+ dev->mtd.priv = dev;
+ dev->mtd.owner = THIS_MODULE;
++ dev->mtd.refresh_device = block2mtd_refresh;
+
+ part = kzalloc(sizeof(struct mtd_partition), GFP_KERNEL);
+ part->name = dev->mtd.name;
+--- a/drivers/mtd/mtdchar.c
++++ b/drivers/mtd/mtdchar.c
+@@ -18,6 +18,7 @@
+
+ #include <linux/mtd/mtd.h>
+ #include <linux/mtd/compatmac.h>
++#include <linux/mtd/partitions.h>
+
+ #include <asm/uaccess.h>
+
+@@ -814,6 +815,13 @@ static int mtd_ioctl(struct inode *inode
+ file->f_pos = 0;
+ break;
+ }
++#ifdef CONFIG_MTD_PARTITIONS
++ case MTDREFRESH:
++ {
++ ret = refresh_mtd_partitions(mtd);
++ break;
++ }
++#endif
+
+ default:
+ ret = -ENOTTY;
+--- a/include/linux/mtd/mtd.h
++++ b/include/linux/mtd/mtd.h
+@@ -101,6 +101,7 @@ struct mtd_oob_ops {
+ uint8_t *oobbuf;
+ };
+
++struct mtd_info;
+ struct mtd_info {
+ u_char type;
+ uint32_t flags;
+@@ -241,6 +242,9 @@ 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
+@@ -110,6 +110,7 @@ struct otp_info {
+ #define MEMERASE64 _IOW('M', 20, struct erase_info_user64)
+ #define MEMWRITEOOB64 _IOWR('M', 21, struct mtd_oob_buf64)
+ #define MEMREADOOB64 _IOWR('M', 22, struct mtd_oob_buf64)
++#define MTDREFRESH _IO('M', 23)
+
+ /*
+ * Obsolete legacy interface. Keep it in order not to break userspace
projects / openwrt / svn-archive / archive.git / blobdiff