vm_page_grab9
Returns a page from an object
Usage
#include <sys/param.h>
#include <vm/vm.h>
#include <vm/vm_page.h>
vm_page_t
vm_page_grab(vm_object_t object, vm_pindex_t pindex, int allocflags);
Overview
The vm_page_grab() function returns the page at pindex from the given object. If the page exists and is busy, vm_page_grab() will sleep while waiting for it. If the page does not exist, it is allocated. The function sleeps until the allocation request can be satisfied.
The function requires the object to be locked on entry, and returns with the object locked. If the vm_page_grab() function sleeps for any reason, the object lock is temporary dropped.
The vm_page_grab() supports all of the flags supported by vm_page_alloc(9). In addition, vm_page_grab() supports the following flags:
- VM_ALLOC_IGN_SBUSY
-
When waiting for the busy state of the existing page to drain, only test for exclusive busy; ignore the shared busy counter.
Return values
The vm_page_grab() always returns the page.
Releases
56 releases since FreeBSD 5.0-RELEASE; the text changed 33 times.