diff options
| -rw-r--r-- | drivers/mtd/ubi/Kconfig | 3 | ||||
| -rw-r--r-- | drivers/mtd/ubi/cdev.c | 2 | ||||
| -rw-r--r-- | include/mtd/ubi-user.h | 16 |
3 files changed, 18 insertions, 3 deletions
diff --git a/drivers/mtd/ubi/Kconfig b/drivers/mtd/ubi/Kconfig index 3e185e46cf6c..271a842f8c39 100644 --- a/drivers/mtd/ubi/Kconfig +++ b/drivers/mtd/ubi/Kconfig @@ -51,7 +51,8 @@ config MTD_UBI_BEB_LIMIT MTD partitions of the same size, UBI will reserve 40 eraseblocks when attaching a partition. - This option can be overridden by the "mtd=" UBI module parameter. + This option can be overridden by the "mtd=" UBI module parameter or + by the "attach" ioctl. Leave the default value if unsure. diff --git a/drivers/mtd/ubi/cdev.c b/drivers/mtd/ubi/cdev.c index 619f9144f990..7885dc0934ce 100644 --- a/drivers/mtd/ubi/cdev.c +++ b/drivers/mtd/ubi/cdev.c @@ -1011,7 +1011,7 @@ static long ctrl_cdev_ioctl(struct file *file, unsigned int cmd, */ mutex_lock(&ubi_devices_mutex); err = ubi_attach_mtd_dev(mtd, req.ubi_num, req.vid_hdr_offset, - CONFIG_MTD_UBI_BEB_LIMIT); + req.max_beb_per1024); mutex_unlock(&ubi_devices_mutex); if (err < 0) put_mtd_device(mtd); diff --git a/include/mtd/ubi-user.h b/include/mtd/ubi-user.h index 8787349fbafe..53cae1e11e57 100644 --- a/include/mtd/ubi-user.h +++ b/include/mtd/ubi-user.h @@ -222,6 +222,7 @@ enum { * @ubi_num: UBI device number to create * @mtd_num: MTD device number to attach * @vid_hdr_offset: VID header offset (use defaults if %0) + * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs * @padding: reserved for future, not used, has to be zeroed * * This data structure is used to specify MTD device UBI has to attach and the @@ -245,12 +246,25 @@ enum { * be 2KiB-64 bytes = 1984. Note, that this position is not even 512-bytes * aligned, which is OK, as UBI is clever enough to realize this is 4th * sub-page of the first page and add needed padding. + * + * The @max_beb_per1024 is the maximum amount of bad PEBs UBI expects on the + * UBI device per 1024 eraseblocks. This value is often given in an other form + * in the NAND datasheet (min NVB i.e. minimal number of valid blocks). The + * maximum expected bad eraseblocks per 1024 is then: + * 1024 * (1 - MinNVB / MaxNVB) + * Which gives 20 for most NAND devices. This limit is used in order to derive + * amount of eraseblock UBI reserves for handling new bad blocks. If the device + * has more bad eraseblocks than this limit, UBI does not reserve any physical + * eraseblocks for new bad eraseblocks, but attempts to use available + * eraseblocks (if any). The accepted range is 0-768. If 0 is given, the + * default kernel value of %CONFIG_MTD_UBI_BEB_LIMIT will be used. */ struct ubi_attach_req { __s32 ubi_num; __s32 mtd_num; __s32 vid_hdr_offset; - __s8 padding[12]; + __s16 max_beb_per1024; + __s8 padding[10]; }; /** |