On Mon, 30 Aug 2010 13:38:57 -0400 Ben Gardiner bengardiner@nanometrics.ca wrote:
The logic to 'spread' mtd partitions needs to calculate the length in the mtd device, including bad blocks.
This patch introduces a new function, mtd_get_len_incl_bad that can return both the length including bad blocks and whether that length was truncated on the device. This new function will be used by the mtdparts spread command later in this series. The definition of the function is #ifdef'd out in configurations that do not use the new 'mtdparts spread' command.
Signed-off-by: Ben Gardinerbengardiner@nanometrics.ca CC: Scott Wood scottwood@freescale.com
Note: the mtd_get_len_incl_bad() function could also be used by the get_len_incl_bad() function in nand_util.c except for the fact that boards can enable NAND support without enabling MTD support. A note has been added to get_len_incl_bad() to remind us to refactor when/if MTD support is available whenever NAND support is enabled.
V5:
- introduced in v5 of this patchset
drivers/mtd/mtdcore.c | 44 ++++++++++++++++++++++++++++++++++++++++++ drivers/mtd/nand/nand_util.c | 6 +++++ include/linux/mtd/mtd.h | 4 ++- 3 files changed, 53 insertions(+), 1 deletions(-)
diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c index 6eb52ed..cb86657 100644 --- a/drivers/mtd/mtdcore.c +++ b/drivers/mtd/mtdcore.c @@ -142,3 +142,47 @@ void put_mtd_device(struct mtd_info *mtd) c = --mtd->usecount; BUG_ON(c < 0); }
+#if defined(CONFIG_CMD_MTDPARTS_SPREAD) +/**
- mtd_get_len_incl_bad
- Check if length including bad blocks fits into device.
- @param mtd an MTD device
- @param offset offset in flash
- @param length image length
- @return image length including bad blocks in *len_incl_bad and whether or not
the length returned was truncated in *truncated- */
+void mtd_get_len_incl_bad(struct mtd_info *mtd, uint64_t offset,
const uint64_t length, uint64_t *len_incl_bad,int *truncated)+{
- *truncated = 0;
- *len_incl_bad = 0;
- if (!mtd->block_isbad) {
*len_incl_bad = length;return;- }
- uint64_t len_excl_bad = 0;
- uint64_t block_len;
- while (len_excl_bad < length) {
block_len = mtd->erasesize - (offset & (mtd->erasesize - 1));if (!mtd->block_isbad(mtd, offset & ~(mtd->erasesize - 1)))len_excl_bad += block_len;*len_incl_bad += block_len;offset += block_len;if (offset >= mtd->size) {*truncated = 1;break;}- }
If this function is called with offset == mtd->size, you should return length zero and truncated, without calling block_isbad().
-Scott