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Consider the example below for a stripe of 6 volumes, a chunk size of 4096, and an offset of 70000. chunk =3D div_u64(offset, dev->chunk_size) =3D 70000 / 4096 =3D 17 offset =3D chunk * dev->chunk_size =3D 17 * 4096 =3D 69632 disk_offset_wrong =3D div_u64(offset, dev->nr_children) =3D 69632 / 6 =3D 1= 1605 disk_chunk =3D div_u64(chunk, dev->nr_children) =3D 17 / 6 =3D 2 disk_offset =3D disk_chunk * dev->chunk_size =3D 2 * 4096 =3D 8192 Signed-off-by: Sergey Bashirov Reviewed-by: Christoph Hellwig --- fs/nfs/blocklayout/dev.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/nfs/blocklayout/dev.c b/fs/nfs/blocklayout/dev.c index cab8809f0e0f..44306ac22353 100644 --- a/fs/nfs/blocklayout/dev.c +++ b/fs/nfs/blocklayout/dev.c @@ -257,10 +257,11 @@ static bool bl_map_stripe(struct pnfs_block_dev *dev,= u64 offset, struct pnfs_block_dev *child; u64 chunk; u32 chunk_idx; + u64 disk_chunk; u64 disk_offset; =20 chunk =3D div_u64(offset, dev->chunk_size); - div_u64_rem(chunk, dev->nr_children, &chunk_idx); + disk_chunk =3D div_u64_rem(chunk, dev->nr_children, &chunk_idx); =20 if (chunk_idx >=3D dev->nr_children) { dprintk("%s: invalid chunk idx %d (%lld/%lld)\n", @@ -273,7 +274,7 @@ static bool bl_map_stripe(struct pnfs_block_dev *dev, u= 64 offset, offset =3D chunk * dev->chunk_size; =20 /* disk offset of the stripe */ - disk_offset =3D div_u64(offset, dev->nr_children); + disk_offset =3D disk_chunk * dev->chunk_size; =20 child =3D &dev->children[chunk_idx]; child->map(child, disk_offset, map); --=20 2.43.0