read_inode in

/fs/hostfs/hostfs_kern.c exactly consist of....

i require a step wise explaination as i am very much screwed up at the last stage of a project

You need to tell us what you are doing, what you have done and what exactly you need help on. You haven't given us any information.

.....****working on linux 2.6.18****.....

The chief idea about the project is we are trying to insert a change in the ext3 fs regarding the inode access stuff....

and further the project is inspired by the Idea named in this following reference:Indodes in directory entries
http://lwn.net/Articles/190224/

well we are stuck up with the difference between
1:wht are directory entries and wht is dentry
2:wht read-ahead logic in namei.c line no 853
3.The value of variable NAMEI_RA_SIZE is always 8
ie.NAMEI_RA_SIZE =blocks*chunks
for block value why it always considers it as only 4 (assuming tht chunks size remain constant)