On 2010-08-12, at 11:42, Joel Becker wrote: >> +/** >> + * generic_check_addressable - Check addressability of file system >> + * @blocksize_bits: log of file system block size >> + * @num_blocks: number of blocks in file system >> + * >> + * Determine whether a file system with @num_blocks blocks (and a >> + * block size of 2**@blocksize_bits) is addressable by the sector_t >> + * and page cache of the system. Return 0 if so and -EFBIG otherwise. >> + */ >> +int generic_check_addressable(unsigned blocksize_bits, u64 num_blocks) >> +{ >> + u64 last_fs_block = num_blocks - 1; >> + >> + BUG_ON(blocksize_bits < 9); >> + BUG_ON(blocksize_bits > PAGE_CACHE_SHIFT); I'd rather not have a BUG_ON() for a "check" function that may be called with on-disk values by some filesystem. Some filesystems (AFAIR) also handle blocksize > PAGE_SIZE internally, so this helper would not be useful for them. Cheers, Andreas -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html