1. 19 Oct, 2014 1 commit
  2. 26 Oct, 2010 1 commit
    • Boaz Harrosh's avatar
      [SCSI] libosd: Support for scatter gather write/read commands · e96e72c4
      Boaz Harrosh authored
      This patch adds the Scatter-Gather (sg) API to libosd.
      Scatter-gather enables a write/read of multiple none-contiguous
      areas of an object, in a single call. The extents may overlap
      and/or be in any order.
      
      The Scatter-Gather list is sent to the target in what is called
      a "cdb continuation segment". This is yet another possible segment
      in the osd-out-buffer. It is unlike all other segments in that it
      sits before the actual "data" segment (which until now was always
      first), and that it is signed by itself and not part of the data
      buffer. This is because the cdb-continuation-segment is considered
      a spill-over of the CDB data, and is therefor signed under
      OSD_SEC_CAPKEY and higher.
      
      TODO: A new osd_finalize_request_ex version should be supplied so
      the @caps received on the network also contains a size parameter
      and can be spilled over into the "cdb continuation segment".
      
      Thanks to John Chandy <john.chandy@uconn.edu> for the original
      code, and investigations. And the implementation of SG support
      in the osd-target.
      Original-coded-by: default avatarJohn Chandy <john.chandy@uconn.edu>
      Signed-off-by: default avatarBoaz Harrosh <bharrosh@panasas.com>
      Signed-off-by: default avatarJames Bottomley <James.Bottomley@suse.de>
      e96e72c4
  3. 12 Mar, 2009 1 commit