diff options
| author | pbonzini <pbonzini@0c8fb4dd-22a2-4bb5-bc14-6c75a5f43652> | 2014-06-09 13:18:11 +0000 |
|---|---|---|
| committer | pbonzini <pbonzini@0c8fb4dd-22a2-4bb5-bc14-6c75a5f43652> | 2014-06-09 13:18:11 +0000 |
| commit | 5d5206bd9c04f71209730d7a2af3e69ce5e2ed43 (patch) | |
| tree | a32f1162999db4b12f492e8c8cd7c910a1724481 | |
| parent | 37fd0806cd321c9e826599fb61ea27b7528c9582 (diff) | |
virtio-scsi: support well-known logical units
The REPORT LUNS well-known logical unit is useful because it lets you
retrieve information about all targets with a single command. It
also provides an easy way to send a no-op request.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
git-svn-id: https://tools.oasis-open.org/version-control/svn/virtio@381 0c8fb4dd-22a2-4bb5-bc14-6c75a5f43652
| -rw-r--r-- | content.tex | 19 |
1 files changed, 12 insertions, 7 deletions
diff --git a/content.tex b/content.tex index aa8f748..19f1c32 100644 --- a/content.tex +++ b/content.tex @@ -4600,13 +4600,18 @@ struct virtio_scsi_req_cmd { #define VIRTIO_SCSI_S_ACA 3 \end{lstlisting} -\field{lun} addresses a target and logical unit in the -virtio-scsi device's SCSI domain. The only supported format for -\field{lun} is: first byte set to 1, second byte set to target, -third and fourth byte representing a single level LUN structure, -followed by four zero bytes. With this representation, a -virtio-scsi device can serve up to 256 targets and 16384 LUNs per -target. +\field{lun} addresses the REPORT LUNS well-known logical unit, or +a target and logical unit in the virtio-scsi device's SCSI domain. +When used to address the REPORT LUNS logical unit, \field{lun} is 0xC1, +0x01 and six zero bytes. The virtio-scsi device SHOULD implement the +REPORT LUNS well-known logical unit. + +When used to address a target and logical unit, the only supported format +for \field{lun} is: first byte set to 1, second byte set to target, +third and fourth byte representing a single level LUN structure, followed +by four zero bytes. With this representation, a virtio-scsi device can +serve up to 256 targets and 16384 LUNs per target. The device MAY also +support having a well-known logical units in the third and fourth byte. \field{id} is the command identifier (``tag''). |