mtd: add a flags for partitions which should just leave smth. after them

Add support for MTDPART_OFS_RETAIN: such partitions start at the current
offset, take as much space as possible, but rain part->size bytes after
the end of the partitions for other parts. Primarily this is intended
for ts72xx arm platforms cleanup.

Artem: tweaked the patch a bit

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
This commit is contained in:
Dmitry Eremin-Solenikov 2011-06-06 18:04:14 +04:00 committed by Artem Bityutskiy
parent bf5140817b
commit 1a31368bf9
2 changed files with 17 additions and 1 deletions

View File

@ -479,6 +479,19 @@ static struct mtd_part *allocate_partition(struct mtd_info *master,
(unsigned long long)cur_offset, (unsigned long long)slave->offset);
}
}
if (slave->offset == MTDPART_OFS_RETAIN) {
slave->offset = cur_offset;
if (master->size - slave->offset >= slave->mtd.size) {
slave->mtd.size = master->size - slave->offset
- slave->mtd.size;
} else {
printk(KERN_ERR "mtd partition \"%s\" doesn't have enough space: %#llx < %#llx, disabled\n",
part->name, master->size - slave->offset,
slave->mtd.size);
/* register to preserve ordering */
goto out_register;
}
}
if (slave->mtd.size == MTDPART_SIZ_FULL)
slave->mtd.size = master->size - slave->offset;

View File

@ -24,7 +24,9 @@
* will extend to the end of the master MTD device.
* offset: absolute starting position within the master MTD device; if
* defined as MTDPART_OFS_APPEND, the partition will start where the
* previous one ended; if MTDPART_OFS_NXTBLK, at the next erase block.
* previous one ended; if MTDPART_OFS_NXTBLK, at the next erase block;
* if MTDPART_OFS_RETAIN, consume as much as possible, leaving size
* after the end of partition.
* mask_flags: contains flags that have to be masked (removed) from the
* master MTD flag set for the corresponding MTD partition.
* For example, to force a read-only partition, simply adding
@ -42,6 +44,7 @@ struct mtd_partition {
struct nand_ecclayout *ecclayout; /* out of band layout for this partition (NAND only) */
};
#define MTDPART_OFS_RETAIN (-3)
#define MTDPART_OFS_NXTBLK (-2)
#define MTDPART_OFS_APPEND (-1)
#define MTDPART_SIZ_FULL (0)