NAME

       daxio - Perform I/O on Device DAX devices or zero a Device DAX device

SYNOPSIS

              $ daxio [<options>]

DESCRIPTION

       The  daxio  utility performs I/O on Device DAX devices or zero a Device DAX device.  Since
       the standard I/O APIs (read/write) cannot be  used  with  Device  DAX,  data  transfer  is
       performed  on  a memory-mapped device.  The daxio may be used to dump Device DAX data to a
       file, restore data from a backup copy, move/copy data to another device or to  erase  data
       from a device.

       There  must  be at least one Device DAX device involved either as the input or output.  If
       input or output is not specified, it will default to stdin or stdout respectively.

       No length specified will default to input file/device length or to the output  file/device
       length, if input is a special char file or stdin.

       For a Device DAX device, daxio will attempt to clear bad blocks within the range of writes
       before performing the I/O (it can be turned off using the `–clear-bad-blocks=no' option).

OPTIONS

       -i, --input Input device or file to read from.

       -o, --output Output device or file to write to.

       -z, --zero Zero the output device for len size, or the entire  device  if  no  length  was
       provided.  The output device must be a Device DAX device.

       -b,  --clear-bad-blocks=<yes|no>  Clear  bad  blocks  within  the  range  of writes before
       performing the I/O (default: yes).

       -l, --len The length in bytes to perform the I/O.  To make  passing  in  size  easier  for
       kibi,  mebi,  gibi,  and  tebi bytes, len may include unit suffix.  The len format must be
       compliant with the format specified in IEC 80000-13, IEEE 1541 or the  Metric  Interchange
       Format.   These standards accept SI units with obligatory B - kB, MB, GB, ...  (multiplier
       by 1000) suffixes, and IEC units with optional “iB” - KiB, MiB, GiB, ...,  K,  M,  G,  ...
       (multiplier by 1024) suffixes.

       -s,  --seek The number of bytes to skip over on the output before performing a write.  The
       same suffixes are accepted as for len.

       -k, --skip The number of bytes to skip over on the input before performing  a  read.   The
       same suffixes are accepted as for len.

       -V, --version

       Prints the version of daxio.

       -h, --help

       Prints synopsis and list of options.

EXAMPLE

              # daxio --zero /dev/dax1.0

              # daxio --input=/dev/dax1.0 --output=/home/myfile --len=2M --seek=4096

              # cat /dev/zero | daxio --output=/dev/dax1.0

              # daxio --input=/dev/zero --output=/dev/dax1.0 --skip=4096

SEE ALSO

       daxctl(1), ndctl(1) and <https://pmem.io>