Hello, Thanks for the feedback on the previous patch series. A updated patch series with the same function as the first patch (https://lkml.org/lkml/2020/10/22/1058 "md: align superblock writes to physical blocks") follows. As suggested, it introduces a helper function, which can be used to reduce some code duplication. It handles the case in super_1_sync() where the superblock is extended by the addition of new component devices. I think it also fixes a bug where the existing code in super_1_load() ought to be rejecting the array with EINVAL: if the superblock padded out to the *logical* block length runs into the bitmap. For example, if the bitmap offset is 2 (bitmap 1K after superblock) and the logical block size is 4K, the superblock padded out to 4K runs into the bitmap. This case may be unusual (perhaps only happens if the array is created on a 512n device and then raw contents are copied onto a 4kn device) but I think it is possible. With respect to the option of simply replacing queue_logical_block_size() with queue_physical_block_size(), I think this can result in the code rejecting devices that can be loaded, but for which the physical block alignment can't be respected--the longer padded size would trigger the EINVAL cases testing against data_offset/new_data_offset. I think it's better to proceed in such cases, just with unaligned superblock writes as would presently happen. Also if I'm right about the above bug, then I think this subsitution would be more likely to trigger it. Thanks, --Chris Christopher Unkel (3): md: factor out repeated sb alignment logic md: align superblock writes to physical blocks md: reuse sb length-checking logic drivers/md/md.c | 69 +++++++++++++++++++++++++++++++++++++------------ 1 file changed, 52 insertions(+), 17 deletions(-) -- 2.17.1
