vmem_xalloc(9) - NetBSD Manual Pages

VMEM_XALLOC(9)         NetBSD Kernel Developer's Manual         VMEM_XALLOC(9)


NAME

     vmem_xalloc -- Allocate resource from arena


SYNOPSIS

     #include <sys/vmem.h>

     vmem_addr_t
     vmem_xalloc(vmem_t *vm, vmem_size_t size, vmem_size_t align,
         vmem_size_t phase, vmem_size_t nocross, vmem_addr_t minaddr,
         vmem_addr_t maxaddr, vm_flag_t flags);


DESCRIPTION

     vmem_xalloc() allocates a resource from the arena.

     vm       The arena which we allocate from.

     size     Specify the size of the allocation.

     align    If zero, don't care about the alignment of the allocation.  Oth-
              erwise, request a resource segment starting at offset phase from
              an align aligned boundary.

     phase    See the above description of align.  If align is zero, phase
              should be zero.  Otherwise, phase should be smaller than align.

     nocross  Request a resource which doesn't cross nocross aligned boundary.

     minaddr  If non-zero, specify the minimum address which can be allocated.

     maxaddr  If non-zero, specify the maximum address + 1 which can be allo-
              cated.

     flags    A bitwise OR of an allocation strategy and a sleep flag.

              The allocation strategy is one of:

              VM_BESTFIT     Prefer space efficiency.

              VM_INSTANTFIT  Prefer performance.

              The sleep flag should be one of:

              VM_SLEEP    Can sleep until enough resources are available.

              VM_NOSLEEP  Don't sleep.  Immediately return VMEM_ADDR_NULL if
                          there are not enough resources available.


RETURN VALUES

     On success, vmem_xalloc() returns an allocated vmem_addr_t.  Otherwise,
     it returns VMEM_ADDR_NULL.


SEE ALSO

     intro(9), vmem(9)

NetBSD 5.0                     November 4, 2006                     NetBSD 5.0