Count for pagination

The main search screen of my application has pagination.

I am basically running 3 queries with the same where clause.

1. Totals for the entire results(not just the number of rows on the
first page)
a. <300 ms
2. Subset of the total records for one page.
a. 1-2 sec
3. Count of the total records for the pagination to show the number of
pages
a. 1-2 sec

The queries are generated by Hibernate and I am looking to rewrite them
in native SQL
to improve performance.

Any suggestions on how to get the count of all records that could be
returned and only
a subset of those records for that page in an optimized fashion? I
have no problem using
a widow query or a Postgres specific feature as my app only runs on
Postgres.