Hi,
This function yields the number of avail pages (pages that exist and are
not mapped to kernels or pre-uvm data) in a given address range.
Beck needs this.
Ok?
--
Ariane
Index: uvm/uvm_page.c
===================================================================
RCS file: /cvs/src/sys/uvm/uvm_page.c,v
retrieving revision 1.102
diff -u -d -p -r1.102 uvm_page.c
--- uvm/uvm_page.c 7 Aug 2010 03:50:02 -0000 1.102
+++ uvm/uvm_page.c 1 Apr 2011 19:20:03 -0000
@@ -1464,3 +1464,28 @@ uvm_page_lookup_freelist(struct vm_page
return (vm_physmem[lcv].free_list);
#endif
}
+
+/*
+ * uvm_pagecount: count the number of physical pages in the address range.
+ */
+psize_t
+uvm_pagecount(struct uvm_constraint_range* constraint)
+{
+ int lcv;
+ psize_t sz;
+ paddr_t low, high;
+ paddr_t ps_low, ps_high;
+
+ /* Algorithm uses page numbers. */
+ low = atop(constraint->ucr_low);
+ high = atop(constraint->ucr_high);
+
+ sz = 0;
+ for (lcv = 0; lcv < vm_nphysseg; lcv++) {
+ ps_low = MAX(low, vm_physmem[lcv].avail_start);
+ ps_high = MIN(high, vm_physmem[lcv].avail_end);
+ if (ps_low < ps_high)
+ sz += ps_high - ps_low;
+ }
+ return sz;
+}
Index: uvm/uvm_page.h
===================================================================
RCS file: /cvs/src/sys/uvm/uvm_page.h,v
retrieving revision 1.44
diff -u -d -p -r1.44 uvm_page.h
--- uvm/uvm_page.h 29 Jun 2010 21:25:16 -0000 1.44
+++ uvm/uvm_page.h 1 Apr 2011 19:20:03 -0000
@@ -252,6 +252,9 @@ void uvm_pagezero(struct vm_page *);
void uvm_pagealloc_pg(struct vm_page *, struct uvm_object *,
voff_t, struct vm_anon *);
+struct uvm_constraint_range; /* XXX move to uvm_extern.h? */
+psize_t uvm_pagecount(struct uvm_constraint_range*);
+
int uvm_page_lookup_freelist(struct vm_page *);
#if VM_PHYSSEG_MAX == 1
