On Fri, Jun 15, 2012 at 09:19:23AM +0000, Arnd Bergmann wrote: > > The trouble is that detecting the erase block size requires us to > write specific patterns to the device, which is generally a bad > idea after the file system has been created. How much space do you need? It's not hard to allocate a bunch of space, in a file, use FIEMAP ioctl to verify that you have a contiguous range of blocks, and then do direct I/O into that region. > I think the best we can do is > > * default to "unspecified" as before > * if "unspecified", make the file system ask the block device. in > case of eMMC, that will usually be reliable > * Add an option to mkfs and tunefs to hardcode a specific size for > users that know the size and can't rely on the blockdev reporting > it correctly to the file system. > * Add an option to mkfs to autodetect the size for the drive it's > run on. Well, I think we can do better; the question is whether or not it's worth the effort. It may not be.... - Ted -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
