vm_pageout: reduce number of flush() params

[dougm]

Summary

vm_pageout_flush is called in two places, and in both, the mreq parameter is 0. Drop that parameter, and simplify the calculations that use it.

The prunlen and eio parameters are either both NULL, or neither NULL. Drop the prunlen parameter and, when eio is NULL, return the runlen value instead of the numpagedout parameter, which the caller ignores.

[markj]

sys/vm/vm_pageout.c

457

sys/vm/vm_pageout.h

103

Consider changing the boolean_t to a plain bool since you're changing this anyway: we're gradually removing uses of the former from the tree.

[alc]

sys/vm/vm_pageout.c

454

sys/vm/vm_pageout.h

103

[alc]

sys/vm/vm_pageout.c

546

This causes the for loop to end. Before, it kept going.