questions on page cache and buffers

Darin Johnson (darin@connectnet.com)
Wed, 6 Aug 1997 19:31:27 -0700 (PDT)


Does the page cache relate to buffers at all? From what I can tell,
the page cache and file data buffers are independent. However,
the "generic_file_read" uses page cache, but a filesystem that
implements file read would use the buffers. But the two caches
have differing hash methods and algorithms to free them, etc.

Also, what would happen if read() used buffers while read_page()
had the same data in page cache? Wouldn't there be duplicated
information in memory?

(I'm thinking of building a memory/swap based filesystem, and
am trying to get a handle on how the page cache interracts with
the typical file handling code)