[sheepdog] [PATCH v1 0/5] replace structure of inode->data_vdi_id[] from array to b-tree

[Robin Dong]

Hi all,

The size of vdi can only reach 4TB beacause the inode->data_vdi_id[] can only
support 1 million objects. But the 4TB is too small for storage application
such as NAS and cloud-disk, so we need to change the array of 'data_vdi_id' to
b-tree.

This patchset add b-tree structure into sd_inode. It support just two levels
(one root-node and many leaf-nodes) and after this the size of vdi could reach about
(4MB / sizeof(sd_extent_header) * (4MB / sizeof(sd_extent)) * 4MB = 1024PB which
is certainly enough for many storage requirement.

Thanks,
Robin Dong