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Diffstat (limited to 'target/linux/generic-2.6/patches-2.6.22/065-rootfs_split.patch')
-rw-r--r--target/linux/generic-2.6/patches-2.6.22/065-rootfs_split.patch944
1 files changed, 0 insertions, 944 deletions
diff --git a/target/linux/generic-2.6/patches-2.6.22/065-rootfs_split.patch b/target/linux/generic-2.6/patches-2.6.22/065-rootfs_split.patch
deleted file mode 100644
index 12723d8..0000000
--- a/target/linux/generic-2.6/patches-2.6.22/065-rootfs_split.patch
+++ /dev/null
@@ -1,944 +0,0 @@
---- a/drivers/mtd/Kconfig
-+++ b/drivers/mtd/Kconfig
-@@ -47,6 +47,16 @@
- 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
-@@ -20,6 +20,8 @@
- #include <linux/mtd/mtd.h>
- #include <linux/mtd/partitions.h>
- #include <linux/mtd/compatmac.h>
-+#include <linux/squashfs_fs.h>
-+#include <linux/root_dev.h>
-
- /* Our partition linked list */
- static LIST_HEAD(mtd_partitions);
-@@ -39,7 +41,7 @@
- * 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
-@@ -308,6 +310,312 @@
- return 0;
- }
-
-+static u_int32_t cur_offset = 0;
-+static int add_one_partition(struct mtd_info *master, const struct mtd_partition *part,
-+ int i, struct mtd_part **slp)
-+{
-+ struct mtd_part *slave;
-+
-+ /* allocate the partition structure */
-+ slave = kzalloc (sizeof(*slave), GFP_KERNEL);
-+ if (!slave) {
-+ printk ("memory allocation error while creating partitions for \"%s\"\n",
-+ master->name);
-+ del_mtd_partitions(master);
-+ return -ENOMEM;
-+ }
-+ list_add(&slave->list, &mtd_partitions);
-+
-+ /* set up the MTD object for this partition */
-+ slave->mtd.type = master->type;
-+ slave->mtd.flags = master->flags & ~part->mask_flags;
-+ slave->mtd.size = part->size;
-+ slave->mtd.writesize = master->writesize;
-+ slave->mtd.oobsize = master->oobsize;
-+ slave->mtd.oobavail = master->oobavail;
-+ slave->mtd.subpage_sft = master->subpage_sft;
-+
-+ slave->mtd.name = part->name;
-+ slave->mtd.owner = master->owner;
-+
-+ slave->mtd.read = part_read;
-+ slave->mtd.write = part_write;
-+ slave->mtd.refresh_device = part->refresh_partition;
-+
-+ if(master->point && master->unpoint){
-+ slave->mtd.point = part_point;
-+ slave->mtd.unpoint = part_unpoint;
-+ }
-+
-+ if (master->read_oob)
-+ slave->mtd.read_oob = part_read_oob;
-+ if (master->write_oob)
-+ slave->mtd.write_oob = part_write_oob;
-+ if(master->read_user_prot_reg)
-+ slave->mtd.read_user_prot_reg = part_read_user_prot_reg;
-+ if(master->read_fact_prot_reg)
-+ slave->mtd.read_fact_prot_reg = part_read_fact_prot_reg;
-+ if(master->write_user_prot_reg)
-+ slave->mtd.write_user_prot_reg = part_write_user_prot_reg;
-+ if(master->lock_user_prot_reg)
-+ slave->mtd.lock_user_prot_reg = part_lock_user_prot_reg;
-+ if(master->get_user_prot_info)
-+ slave->mtd.get_user_prot_info = part_get_user_prot_info;
-+ if(master->get_fact_prot_info)
-+ slave->mtd.get_fact_prot_info = part_get_fact_prot_info;
-+ if (master->sync)
-+ slave->mtd.sync = part_sync;
-+ if (!i && master->suspend && master->resume) {
-+ slave->mtd.suspend = part_suspend;
-+ slave->mtd.resume = part_resume;
-+ }
-+ if (master->writev)
-+ slave->mtd.writev = part_writev;
-+ if (master->lock)
-+ slave->mtd.lock = part_lock;
-+ if (master->unlock)
-+ slave->mtd.unlock = part_unlock;
-+ if (master->block_isbad)
-+ slave->mtd.block_isbad = part_block_isbad;
-+ if (master->block_markbad)
-+ slave->mtd.block_markbad = part_block_markbad;
-+ slave->mtd.erase = part_erase;
-+ slave->master = master;
-+ slave->offset = part->offset;
-+ slave->index = i;
-+
-+ if (slave->offset == MTDPART_OFS_APPEND)
-+ slave->offset = cur_offset;
-+ if (slave->offset == MTDPART_OFS_NXTBLK) {
-+ slave->offset = cur_offset;
-+ if ((cur_offset % master->erasesize) != 0) {
-+ /* Round up to next erasesize */
-+ slave->offset = ((cur_offset / master->erasesize) + 1) * master->erasesize;
-+ printk(KERN_NOTICE "Moving partition %d: "
-+ "0x%08x -> 0x%08x\n", i,
-+ cur_offset, slave->offset);
-+ }
-+ }
-+ if (slave->mtd.size == MTDPART_SIZ_FULL)
-+ slave->mtd.size = master->size - slave->offset;
-+ cur_offset = slave->offset + slave->mtd.size;
-+
-+ printk (KERN_NOTICE "0x%08x-0x%08x : \"%s\"\n", slave->offset,
-+ slave->offset + slave->mtd.size, slave->mtd.name);
-+
-+ /* let's do some sanity checks */
-+ if (slave->offset >= master->size) {
-+ /* let's register it anyway to preserve ordering */
-+ slave->offset = 0;
-+ slave->mtd.size = 0;
-+ printk ("mtd: partition \"%s\" is out of reach -- disabled\n",
-+ part->name);
-+ }
-+ if (slave->offset + slave->mtd.size > master->size) {
-+ slave->mtd.size = master->size - slave->offset;
-+ printk ("mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#x\n",
-+ part->name, master->name, slave->mtd.size);
-+ }
-+ if (master->numeraseregions>1) {
-+ /* Deal with variable erase size stuff */
-+ int i;
-+ struct mtd_erase_region_info *regions = master->eraseregions;
-+
-+ /* Find the first erase regions which is part of this partition. */
-+ for (i=0; i < master->numeraseregions && slave->offset >= regions[i].offset; i++)
-+ ;
-+
-+ for (i--; i < master->numeraseregions && slave->offset + slave->mtd.size > regions[i].offset; i++) {
-+ if (slave->mtd.erasesize < regions[i].erasesize) {
-+ slave->mtd.erasesize = regions[i].erasesize;
-+ }
-+ }
-+ } else {
-+ /* Single erase size */
-+ slave->mtd.erasesize = master->erasesize;
-+ }
-+
-+ if ((slave->mtd.flags & MTD_WRITEABLE) &&
-+ (slave->offset % slave->mtd.erasesize)) {
-+ /* Doesn't start on a boundary of major erase size */
-+ /* FIXME: Let it be writable if it is on a boundary of _minor_ erase size though */
-+ slave->mtd.flags &= ~MTD_WRITEABLE;
-+ printk ("mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n",
-+ part->name);
-+ }
-+ if ((slave->mtd.flags & MTD_WRITEABLE) &&
-+ (slave->mtd.size % slave->mtd.erasesize)) {
-+ slave->mtd.flags &= ~MTD_WRITEABLE;
-+ printk ("mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n",
-+ part->name);
-+ }
-+
-+ slave->mtd.ecclayout = master->ecclayout;
-+ if (master->block_isbad) {
-+ uint32_t offs = 0;
-+
-+ while(offs < slave->mtd.size) {
-+ if (master->block_isbad(master,
-+ offs + slave->offset))
-+ slave->mtd.ecc_stats.badblocks++;
-+ offs += slave->mtd.erasesize;
-+ }
-+ }
-+
-+ if(part->mtdp)
-+ { /* store the object pointer (caller may or may not register it */
-+ *part->mtdp = &slave->mtd;
-+ slave->registered = 0;
-+ }
-+ else
-+ {
-+ /* register our partition */
-+ add_mtd_device(&slave->mtd);
-+ slave->registered = 1;
-+ }
-+
-+ if (slp)
-+ *slp = slave;
-+
-+ return 0;
-+}
-+
-+#ifdef CONFIG_MTD_ROOTFS_SPLIT
-+#define ROOTFS_SPLIT_NAME "rootfs_data"
-+#define ROOTFS_REMOVED_NAME "<removed>"
-+static int split_squashfs(struct mtd_info *master, int offset, int *split_offset)
-+{
-+ char buf[512];
-+ struct squashfs_super_block *sb = (struct squashfs_super_block *) buf;
-+ int len, ret;
-+
-+ ret = master->read(master, offset, sizeof(*sb), &len, buf);
-+ if (ret || (len != sizeof(*sb))) {
-+ printk(KERN_ALERT "split_squashfs: error occured while reading "
-+ "from \"%s\"\n", master->name);
-+ return -EINVAL;
-+ }
-+
-+ if (*((u32 *) buf) != SQUASHFS_MAGIC) {
-+ printk(KERN_ALERT "split_squasfs: no squashfs found in \"%s\"\n",
-+ master->name);
-+ *split_offset = 0;
-+ return 0;
-+ }
-+
-+ if (sb->bytes_used <= 0) {
-+ printk(KERN_ALERT "split_squashfs: squashfs is empty in \"%s\"\n",
-+ master->name);
-+ *split_offset = 0;
-+ return 0;
-+ }
-+
-+ len = (u32) 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, struct mtd_partition *part,
-+ int index)
-+{
-+ 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=%X, len=%X \n",
-+ ROOTFS_SPLIT_NAME, dpart->offset, dpart->size);
-+
-+ ret = add_one_partition(master, dpart, index, &slave);
-+ if (ret)
-+ kfree(dpart);
-+ else if (slave)
-+ rpart->split = &slave->mtd;
-+
-+ return ret;
-+}
-+
-+static int refresh_rootfs_split(struct mtd_info *mtd)
-+{
-+ struct mtd_partition tpart;
-+ struct mtd_part *part;
-+ 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 = mtd->name;
-+ tpart.size = mtd->size;
-+ tpart.offset = part->offset;
-+
-+ /* find the index of the last partition */
-+ if (!list_empty(&mtd_partitions))
-+ index = list_first_entry(&mtd_partitions, struct mtd_part, list)->index + 1;
-+
-+ return split_rootfs_data(part->master, &part->mtd, &tpart, index);
-+ } 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"),
-+ part->offset, part->mtd.size);
-+ strcpy(part->mtd.name, ROOTFS_SPLIT_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);
-+ strcpy(part->mtd.name, ROOTFS_REMOVED_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
-@@ -320,168 +628,31 @@
- int nbparts)
- {
- struct mtd_part *slave;
-- u_int32_t cur_offset = 0;
-- int i;
-+ struct mtd_partition *part;
-+ int i, j, ret = 0;
-
- printk (KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
-
-- for (i = 0; i < nbparts; i++) {
--
-- /* allocate the partition structure */
-- slave = kzalloc (sizeof(*slave), GFP_KERNEL);
-- if (!slave) {
-- printk ("memory allocation error while creating partitions for \"%s\"\n",
-- master->name);
-- del_mtd_partitions(master);
-- return -ENOMEM;
-- }
-- list_add(&slave->list, &mtd_partitions);
--
-- /* set up the MTD object for this partition */
-- slave->mtd.type = master->type;
-- slave->mtd.flags = master->flags & ~parts[i].mask_flags;
-- slave->mtd.size = parts[i].size;
-- slave->mtd.writesize = master->writesize;
-- slave->mtd.oobsize = master->oobsize;
-- slave->mtd.oobavail = master->oobavail;
-- slave->mtd.subpage_sft = master->subpage_sft;
--
-- slave->mtd.name = parts[i].name;
-- slave->mtd.owner = master->owner;
--
-- slave->mtd.read = part_read;
-- slave->mtd.write = part_write;
--
-- if(master->point && master->unpoint){
-- slave->mtd.point = part_point;
-- slave->mtd.unpoint = part_unpoint;
-- }
--
-- if (master->read_oob)
-- slave->mtd.read_oob = part_read_oob;
-- if (master->write_oob)
-- slave->mtd.write_oob = part_write_oob;
-- if(master->read_user_prot_reg)
-- slave->mtd.read_user_prot_reg = part_read_user_prot_reg;
-- if(master->read_fact_prot_reg)
-- slave->mtd.read_fact_prot_reg = part_read_fact_prot_reg;
-- if(master->write_user_prot_reg)
-- slave->mtd.write_user_prot_reg = part_write_user_prot_reg;
-- if(master->lock_user_prot_reg)
-- slave->mtd.lock_user_prot_reg = part_lock_user_prot_reg;
-- if(master->get_user_prot_info)
-- slave->mtd.get_user_prot_info = part_get_user_prot_info;
-- if(master->get_fact_prot_info)
-- slave->mtd.get_fact_prot_info = part_get_fact_prot_info;
-- if (master->sync)
-- slave->mtd.sync = part_sync;
-- if (!i && master->suspend && master->resume) {
-- slave->mtd.suspend = part_suspend;
-- slave->mtd.resume = part_resume;
-- }
-- if (master->writev)
-- slave->mtd.writev = part_writev;
-- if (master->lock)
-- slave->mtd.lock = part_lock;
-- if (master->unlock)
-- slave->mtd.unlock = part_unlock;
-- if (master->block_isbad)
-- slave->mtd.block_isbad = part_block_isbad;
-- if (master->block_markbad)
-- slave->mtd.block_markbad = part_block_markbad;
-- slave->mtd.erase = part_erase;
-- slave->master = master;
-- slave->offset = parts[i].offset;
-- slave->index = i;
--
-- if (slave->offset == MTDPART_OFS_APPEND)
-- slave->offset = cur_offset;
-- if (slave->offset == MTDPART_OFS_NXTBLK) {
-- slave->offset = cur_offset;
-- if ((cur_offset % master->erasesize) != 0) {
-- /* Round up to next erasesize */
-- slave->offset = ((cur_offset / master->erasesize) + 1) * master->erasesize;
-- printk(KERN_NOTICE "Moving partition %d: "
-- "0x%08x -> 0x%08x\n", i,
-- cur_offset, slave->offset);
-- }
-- }
-- if (slave->mtd.size == MTDPART_SIZ_FULL)
-- slave->mtd.size = master->size - slave->offset;
-- cur_offset = slave->offset + slave->mtd.size;
--
-- printk (KERN_NOTICE "0x%08x-0x%08x : \"%s\"\n", slave->offset,
-- slave->offset + slave->mtd.size, slave->mtd.name);
--
-- /* let's do some sanity checks */
-- if (slave->offset >= master->size) {
-- /* let's register it anyway to preserve ordering */
-- slave->offset = 0;
-- slave->mtd.size = 0;
-- printk ("mtd: partition \"%s\" is out of reach -- disabled\n",
-- parts[i].name);
-- }
-- if (slave->offset + slave->mtd.size > master->size) {
-- slave->mtd.size = master->size - slave->offset;
-- printk ("mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#x\n",
-- parts[i].name, master->name, slave->mtd.size);
-- }
-- if (master->numeraseregions>1) {
-- /* Deal with variable erase size stuff */
-- int i;
-- struct mtd_erase_region_info *regions = master->eraseregions;
--
-- /* Find the first erase regions which is part of this partition. */
-- for (i=0; i < master->numeraseregions && slave->offset >= regions[i].offset; i++)
-- ;
--
-- for (i--; i < master->numeraseregions && slave->offset + slave->mtd.size > regions[i].offset; i++) {
-- if (slave->mtd.erasesize < regions[i].erasesize) {
-- slave->mtd.erasesize = regions[i].erasesize;
-- }
-+ for (i = 0, j = 0; i < nbparts; i++) {
-+ part = (struct mtd_partition *) &parts[i];
-+ ret = add_one_partition(master, part, j, &slave);
-+ if (ret)
-+ return ret;
-+ j++;
-+
-+ if (strcmp(part->name, "rootfs") == 0 && slave->registered) {
-+#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);
- }
-- } else {
-- /* Single erase size */
-- slave->mtd.erasesize = master->erasesize;
-- }
--
-- if ((slave->mtd.flags & MTD_WRITEABLE) &&
-- (slave->offset % slave->mtd.erasesize)) {
-- /* Doesn't start on a boundary of major erase size */
-- /* FIXME: Let it be writable if it is on a boundary of _minor_ erase size though */
-- slave->mtd.flags &= ~MTD_WRITEABLE;
-- printk ("mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n",
-- parts[i].name);
-- }
-- if ((slave->mtd.flags & MTD_WRITEABLE) &&
-- (slave->mtd.size % slave->mtd.erasesize)) {
-- slave->mtd.flags &= ~MTD_WRITEABLE;
-- printk ("mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n",
-- parts[i].name);
-- }
--
-- slave->mtd.ecclayout = master->ecclayout;
-- if (master->block_isbad) {
-- uint32_t offs = 0;
--
-- while(offs < slave->mtd.size) {
-- if (master->block_isbad(master,
-- offs + slave->offset))
-- slave->mtd.ecc_stats.badblocks++;
-- offs += slave->mtd.erasesize;
-- }
-- }
--
-- if(parts[i].mtdp)
-- { /* store the object pointer (caller may or may not register it */
-- *parts[i].mtdp = &slave->mtd;
-- slave->registered = 0;
-- }
-- else
-- {
-- /* register our partition */
-- add_mtd_device(&slave->mtd);
-- slave->registered = 1;
-+#endif
-+#ifdef CONFIG_MTD_ROOTFS_SPLIT
-+ ret = split_rootfs_data(master, &slave->mtd, part, j);
-+ if (ret == 0)
-+ j++;
-+#endif
- }
- }
-
-@@ -557,6 +728,32 @@
- return ret;
- }
-
-+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(parse_mtd_partitions);
-+EXPORT_SYMBOL_GPL(refresh_mtd_partitions);
- EXPORT_SYMBOL_GPL(register_mtd_parser);
- EXPORT_SYMBOL_GPL(deregister_mtd_parser);
---- a/drivers/mtd/devices/block2mtd.c
-+++ b/drivers/mtd/devices/block2mtd.c
-@@ -34,6 +34,8 @@
- struct block_device *blkdev;
- struct mtd_info mtd;
- struct mutex write_mutex;
-+ rwlock_t bdev_mutex;
-+ char devname[0];
- };
-
-
-@@ -86,6 +88,12 @@
- 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);
-@@ -98,6 +106,10 @@
-
- instr->state = MTD_ERASE_DONE;
- mtd_erase_callback(instr);
-+
-+done:
-+ read_unlock(&dev->bdev_mutex);
-+
- return err;
- }
-
-@@ -109,10 +121,14 @@
- 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;
-
-@@ -127,10 +143,14 @@
- 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);
-@@ -141,7 +161,10 @@
- offset = 0;
- index++;
- }
-- return 0;
-+
-+done:
-+ read_unlock(&dev->bdev_mutex);
-+ return err;
- }
-
-
-@@ -193,12 +216,22 @@
- 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;
-
-@@ -207,6 +240,9 @@
- mutex_unlock(&dev->write_mutex);
- if (err > 0)
- err = 0;
-+
-+done:
-+ read_unlock(&dev->bdev_mutex);
- return err;
- }
-
-@@ -215,51 +251,29 @@
- 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_excl(dev->blkdev);
-- }
-+ 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, char *mtdname)
-+static int _open_bdev(struct block2mtd_dev *dev)
- {
- struct block_device *bdev;
-- struct block2mtd_dev *dev;
-- struct mtd_partition *part;
--
-- 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_excl(devname, O_RDWR, NULL);
-+ bdev = open_bdev_excl(dev->devname, O_RDWR, 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);
- }
-@@ -267,17 +281,96 @@
- #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_excl(dev->blkdev);
-+ 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;
-+ else {
-+ err = rescan_partitions(bdev->bd_disk, bdev);
-+ }
-+ if (bdev)
-+ close_bdev_excl(bdev);
-+
-+ /* 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;
-+
-+ 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);
-
- /* Setup the MTD structure */
- /* make the name contain the block device in */
-@@ -304,6 +397,7 @@
- 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
-@@ -16,6 +16,7 @@
-
- #include <linux/mtd/mtd.h>
- #include <linux/mtd/compatmac.h>
-+#include <linux/mtd/partitions.h>
-
- #include <asm/uaccess.h>
-
-@@ -752,6 +753,13 @@
- 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
-@@ -98,6 +98,7 @@
- uint8_t *oobbuf;
- };
-
-+struct mtd_info;
- struct mtd_info {
- u_char type;
- u_int32_t flags;
-@@ -195,6 +196,9 @@
- struct module *owner;
- 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
-@@ -36,6 +36,7 @@
- * erasesize aligned (e.g. use MTDPART_OFS_NEXTBLK).
- */
-
-+struct mtd_partition;
- struct mtd_partition {
- char *name; /* identifier string */
- u_int32_t size; /* partition size */
-@@ -43,6 +44,7 @@
- u_int32_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)*/
- struct mtd_info **mtdp; /* pointer to store the MTD object */
-+ int (*refresh_partition)(struct mtd_info *);
- };
-
- #define MTDPART_OFS_NXTBLK (-2)
-@@ -52,6 +54,7 @@
-
- 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
-@@ -95,6 +95,7 @@
- #define ECCGETLAYOUT _IOR('M', 17, struct nand_ecclayout)
- #define ECCGETSTATS _IOR('M', 18, struct mtd_ecc_stats)
- #define MTDFILEMODE _IO('M', 19)
-+#define MTDREFRESH _IO('M', 23)
-
- /*
- * Obsolete legacy interface. Keep it in order not to break userspace