diff options
| -rw-r--r-- | drivers/mtd/mtdconcat.c | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/drivers/mtd/mtdconcat.c b/drivers/mtd/mtdconcat.c index 3dbb1b38db66..792b547786b8 100644 --- a/drivers/mtd/mtdconcat.c +++ b/drivers/mtd/mtdconcat.c @@ -13,6 +13,7 @@ #include <linux/slab.h> #include <linux/sched.h> #include <linux/types.h> +#include <linux/backing-dev.h> #include <linux/mtd/mtd.h> #include <linux/mtd/concat.h> @@ -684,6 +685,40 @@ static int concat_block_markbad(struct mtd_info *mtd, loff_t ofs) } /* + * try to support NOMMU mmaps on concatenated devices + * - we don't support subdev spanning as we can't guarantee it'll work + */ +static unsigned long concat_get_unmapped_area(struct mtd_info *mtd, + unsigned long len, + unsigned long offset, + unsigned long flags) +{ + struct mtd_concat *concat = CONCAT(mtd); + int i; + + for (i = 0; i < concat->num_subdev; i++) { + struct mtd_info *subdev = concat->subdev[i]; + + if (offset >= subdev->size) { + offset -= subdev->size; + continue; + } + + /* we've found the subdev over which the mapping will reside */ + if (offset + len > subdev->size) + return (unsigned long) -EINVAL; + + if (subdev->get_unmapped_area) + return subdev->get_unmapped_area(subdev, len, offset, + flags); + + break; + } + + return (unsigned long) -ENOSYS; +} + +/* * This function constructs a virtual MTD device by concatenating * num_devs MTD devices. A pointer to the new device object is * stored to *new_dev upon success. This function does _not_ @@ -740,6 +775,8 @@ struct mtd_info *mtd_concat_create(struct mtd_info *subdev[], /* subdevices to c concat->mtd.ecc_stats.badblocks = subdev[0]->ecc_stats.badblocks; + concat->mtd.backing_dev_info = subdev[0]->backing_dev_info; + concat->subdev[0] = subdev[0]; for (i = 1; i < num_devs; i++) { @@ -766,6 +803,15 @@ struct mtd_info *mtd_concat_create(struct mtd_info *subdev[], /* subdevices to c concat->mtd.flags |= subdev[i]->flags & MTD_WRITEABLE; } + + /* only permit direct mapping if the BDIs are all the same + * - copy-mapping is still permitted + */ + if (concat->mtd.backing_dev_info != + subdev[i]->backing_dev_info) + concat->mtd.backing_dev_info = + &default_backing_dev_info; + concat->mtd.size += subdev[i]->size; concat->mtd.ecc_stats.badblocks += subdev[i]->ecc_stats.badblocks; @@ -796,6 +842,7 @@ struct mtd_info *mtd_concat_create(struct mtd_info *subdev[], /* subdevices to c concat->mtd.unlock = concat_unlock; concat->mtd.suspend = concat_suspend; concat->mtd.resume = concat_resume; + concat->mtd.get_unmapped_area = concat_get_unmapped_area; /* * Combine the erase block size info of the subdevices: |