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33 .Nd NVMe Direct Access device driver
40 driver provides support for direct access devices, implementing the
42 command protocol, that are attached to the system through a host adapter
43 supported by the CAM subsystem.
45 The following variables are available as both
51 .It Va kern.cam.nda.sort_io_queue
53 This variable determines whether the software queued entries are
54 sorted in LBA order or not.
55 Sorting is almost always a waste of time.
56 The default is to not sort.
59 The following report per-device settings, and are read-only unless
60 otherwise indicated. Replace
62 with the device unit number.
64 .It Va kern.cam.nda.N.rotating
66 This variable reports whether the storage volume is spinning or
68 It's value is hard coded to 0 indicating flash.
69 .It Va kern.cam.nda.N.unmapped_io
70 This variable reports whether the
72 driver accepts unmapped I/O for this unit.
74 .Bl -tag -width ".Pa /dev/nda*" -compact
76 NVMe storage device nodes
84 driver first appeared in
87 .An Warner Losh Aq Mt imp@FreeBSD.org