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VM_PAGE_GRAB(9) FreeBSD Kernel Developer's Manual VM_PAGE_GRAB(9)
NAME vm_page_grab - returns a page from an object
SYNOPSIS #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);
DESCRIPTION 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.
SEE ALSO vm_page_alloc(9)
AUTHORS This manual page was written by Chad David <davidc@acns.ab.ca>.
FreeBSD 14.0-RELEASE-p11 August 23, 2013 FreeBSD 14.0-RELEASE-p11