clients. In its simplest form it just exchanges 'ldlm_request' and
'ldlm_reply' descriptors of the desired and granted locks.
-.LDLM_ENQUEUE Generic Packet Structure
-image::ldlm-enqueue-generic.png["LDLM_ENQUEUE Generic Packet Structure",height=100]
+However, there are many variants to this RPCs. A lock request may signal
+an intention to carry out an operation once a lock has been
+granted.
+
+.LDLM_ENQUEUE Request Packet Structure
+image::ldlm-enqueue-request.png["LDLM_ENQUEUE Request Packet Structure",height=75]
//////////////////////////////////////////////////////////////////////
-The ldlm-enqueue-generic.png diagram resembles this text
+The ldlm-enqueue-request.png diagram resembles this text
art:
LDLM_ENQUEUE:
--request---------------------
| ptlrpc_body | ldlm_request |
------------------------------
+//////////////////////////////////////////////////////////////////////
+
+'ptlrpc_body'::
+RPC descriptor. See <<struct-ptlrpc-body>>.
+
+include::struct_ldlm_request.txt[]
+
+.LDLM_ENQUEUE Reply Packet Structure
+image::ldlm-enqueue-reply.png["LDLM_ENQUEUE Reply Packet Structure",height=50]
+
+//////////////////////////////////////////////////////////////////////
+The ldlm-enqueue-reply.png diagram resembles this text
+art:
+
+ LDLM_ENQUEUE:
--reply---------------------
| ptlrpc_body | ldlm_reply |
----------------------------
//////////////////////////////////////////////////////////////////////
-However, there are many variants to this RPCs. A lock request may signal
-an intention to carry out an operation once a lock has been
-granted. In the following example, the RPCs are fostering the 'intent'
+'ptlrpc_body'::
+RPC descriptor. See <<struct-ptlrpc-body>>.
+
+include::struct_ldlm_reply.txt[]
+
+****
+In the following example, the RPCs are fostering the 'intent'
to look at how a resource is mapped to the available targets, so
called 'layout' information.
+****
-.LDLM_ENQUEUE Intent:Layout Generic Packet Structure
-image::ldlm-enqueue-intent-layout-generic.png["LDLM_ENQUEUE Intent:Layout Generic Packet Structure",height=100]
+.LDLM_ENQUEUE Intent:Layout Request Packet Structure
+image::ldlm-enqueue-intent-layout-request.png["LDLM_ENQUEUE Intent:Layout Request Packet Structure",height=50]
//////////////////////////////////////////////////////////////////////
-The ldlm-enqueue-intent-layout-generic.png diagram resembles this text
+The ldlm-enqueue-intent-layout-request.png diagram resembles this text
art:
LDLM_ENQUEUE:
--intent:layout request------------------------------------
| ptlrpc_body | ldlm_request |ldlm_intent | layout_intent |
- lov_mds_md |
-----------------------------------------------------------
+ | lov_mds_md |
+ --------------
+//////////////////////////////////////////////////////////////////////
+
+'ptlrpc_body'::
+RPC descriptor. See <<struct-ptlrpc-body>>.
+
+'ldlm_request'::
+The LDLM Request structure. See <<struct-ldlm-request>>.
+
+include::struct_ldlm_intent.txt[]
+
+include::struct_layout_intent.txt[]
+
+include::struct_lov_mds_md.txt[]
+
+.LDLM_ENQUEUE Intent:Layout Reply Packet Structure
+image::ldlm-enqueue-intent-layout-reply.png["LDLM_ENQUEUE Intent:Layout Reply Packet Structure",height=50]
+
+//////////////////////////////////////////////////////////////////////
+The ldlm-enqueue-intent-layout-reply.png diagram resembles this text
+art:
+
+ LDLM_ENQUEUE:
--intent:layout reply--------------------
| ptlrpc_body | ldlm_reply | lov_mds_md |
-----------------------------------------
//////////////////////////////////////////////////////////////////////
+'ptlrpc_body'::
+RPC descriptor. See <<struct-ptlrpc-body>>.
+
+'ldlm_reply'::
+The LDLM Reply structure. See <<struct-ldlm-reply>>.
+
+****
+Lock Value Block::
+A Lock Value Block (LVB) is included in the LDLM_ENQUEUE reply message
+when one of three things needs to be communicated back to the
+requester. The three alternatives are captured by the
+'ost_lvb' structure, the 'lov_mds_md' structure, and one other related
+to quotas (and not yet incorporated into this document). LDLM_ENQUEUE
+reply RPCs may include a zero length instance of an LVB.
+****
+
+'lov_mds_md'::
+The LOV MDS MD structure. See <<struct-lov-mds-md>>.
+
And in this example the intent is to get attribute information.
-.LDLM_ENQUEUE Intent:Getattr Generic Packet Structure
-image::ldlm-enqueue-intent-getattr-generic.png["LDLM_ENQUEUE Intent:Getattr Generic Packet Structure",height=150]
+.LDLM_ENQUEUE Intent:Getattr Request Packet Structure
+image::ldlm-enqueue-intent-getattr-request.png["LDLM_ENQUEUE Intent:Getattr Request Packet Structure",height=50]
//////////////////////////////////////////////////////////////////////
-The ldlm-enqueue-intent-getattr-generic.png diagram resembles this text
+The ldlm-enqueue-intent-getattr-request.png diagram resembles this text
art:
LDLM_ENQUEUE:
--intent:getattr request-------------------------------
| ptlrpc_body | ldlm_request | ldlm_intent | mdt_body |
- lustre_capa |name |
-------------------------------------------------------
+ | lustre_capa | name |
+ ----------------------
+//////////////////////////////////////////////////////////////////////
+
+'ptlrpc_body'::
+RPC descriptor. See <<struct-ptlrpc-body>>.
+
+'ldlm_request'::
+The LDLM Request structure. See <<struct-ldlm-request>>.
+
+'ldlm_intent'::
+The LDLM Intent structure. See <<struct-ldlm-intent>>.
+
+'mdt_body'::
+Metadata about the resource. See <<struct-mdt-body>>.
+
+'lustre_capa'::
+A "capabilities" structure. See <<struct-lustre-capa>>.
+
+'name'::
+A text field supplying the name of the desired resource.
+
+.LDLM_ENQUEUE Intent:Getattr Reply Packet Structure
+image::ldlm-enqueue-intent-getattr-reply.png["LDLM_ENQUEUE Intent:Getattr Reply Packet Structure",height=50]
+
+//////////////////////////////////////////////////////////////////////
+The ldlm-enqueue-intent-getattr-reply.png diagram resembles this text
+art:
+
+ LDLM_ENQUEUE:
--intent:getattr reply--------------------------
| ptlrpc_body | ldlm_reply | mdt_body | mdt_md |
------------------------------------------------
+//////////////////////////////////////////////////////////////////////
+
+'ptlrpc_body'::
+RPC descriptor. See <<struct-ptlrpc-body>>.
+
+'ldlm_reply'::
+The LDLM Reply structure. See <<struct-ldlm-reply>>.
+
+'mdt_body'::
+Metadata about the resource. See <<struct-mdt-body>>.
+
+'mdt_md'::
+Layout data for the resource. This buffer is optional and will appear
+as zero length in some packets.
+
+.LDLM_ENQUEUE Intent:Lvb Reply Packet Structure
+image::ldlm-enqueue-intent-lvb-reply.png["LDLM_ENQUEUE Intent:Lvb Reply Packet Structure",height=50]
+
+//////////////////////////////////////////////////////////////////////
+The ldlm-enqueue-intent-lvb-reply.png diagram resembles this text
+art:
+
+ LDLM_ENQUEUE:
--intent:lvb reply--------------------
| ptlrpc_body | ldlm_reply | ost_lvb |
--------------------------------------
//////////////////////////////////////////////////////////////////////
+'ptlrpc_body'::
+RPC descriptor. See <<struct-ptlrpc-body>>.
+
+'ldlm_reply'::
+The LDLM Reply structure. See <<struct-ldlm-reply>>.
+
+include::struct_ost_lvb.txt[]
+
Here is another example of an intent, in this case the 'getxattr' intent.
-.LDLM_ENQUEUE Intent:Getxattr Generic Packet Structure
-image::ldlm-enqueue-intent-getxattr-generic.png["LDLM_ENQUEUE Intent:Getxattr Generic Packet Structure",height=125]
+.LDLM_ENQUEUE Intent:Getxattr Request Packet Structure
+image::ldlm-enqueue-intent-getxattr-request.png["LDLM_ENQUEUE Intent:Getxattr Request Packet Structure",height=50]
//////////////////////////////////////////////////////////////////////
-The ldlm-enqueue-intent-getxattr-generic.png diagram resembles this text
+The ldlm-enqueue-intent-getxattr-request.png diagram resembles this text
art:
LDLM_ENQUEUE:
- --intent:getxattr request------------------------------------
- | ptlrpc_body | ldlm_request |ldlm_intent | mdt_body | capa |
- -------------------------------------------------------------
- --intent:getxattr reply----------------------------------------
- | ptlrpc_body | ldlm_reply | mdt_body | lov_mds_md | ACL data |
- | EA data | EA vals | EA lens |
- ---------------------------------------------------------------
+ --intent:getxattr request-----------------------------
+ | ptlrpc_body | ldlm_request |ldlm_intent | mdt_body |
+ ------------------------------------------------------
+ | lustre_capa |
+ ---------------
//////////////////////////////////////////////////////////////////////
'ptlrpc_body'::
-RPC descriptor <<struct-ptlrpc-body>>.
+RPC descriptor. See <<struct-ptlrpc-body>>.
-include::struct_ldlm_request.txt[]
+'ldlm_request'::
+The LDLM Request structure. See <<struct-ldlm-request>>.
-include::struct_ldlm_intent.txt[]
-
-include::struct_layout_intent.txt[]
+'ldlm_intent'::
+The LDLM Intent structure. See <<struct-ldlm-intent>>.
'mdt_body'::
-In a request, an indication (in the 'mbo_valid' field) of what
-attributes the requester would like. In a reply, (again based on
-'mbo_valid') the values being returned. <<struct-mdt-body>>
+Metadata about the resource. See <<struct-mdt-body>>.
'lustre_capa'::
-So called "capabilities" structure. This is deprecated in recent
-versions of Lustre, and commonly appears in the packet header as a zero
-length buffer.
+A "capabilities" structure. See <<struct-lustre-capa>>.
-'name'::
-A text field supplying the name of the desired resource.
+.LDLM_ENQUEUE Intent:Getxattr Reply Packet Structure
+image::ldlm-enqueue-intent-getxattr-reply.png["LDLM_ENQUEUE Intent:Getxattr Reply Packet Structure",height=50]
-include::struct_ldlm_reply.txt[]
+//////////////////////////////////////////////////////////////////////
+The ldlm-enqueue-intent-getxattr-reply.png diagram resembles this text
+art:
+
+ LDLM_ENQUEUE:
+ --intent:getxattr reply----------------------------------------
+ | ptlrpc_body | ldlm_reply | mdt_body | lov_mds_md | ACL data |
+ | EA data | EA vals | EA lens |
+ ---------------------------------------------------------------
+//////////////////////////////////////////////////////////////////////
+
+'ptlrpc_body'::
+RPC descriptor. See <<struct-ptlrpc-body>>.
+
+'ldlm_reply'::
+The LDLM Reply structure. See <<struct-ldlm-reply>>.
+
+'mdt_body'::
+Metadata about the resource. See <<struct-mdt-body>>.
+
+'lov_mds_md'::
+The LOV MDS MD structure. See <<struct-lov-mds-md>>.
'ACL data'::
Access Control List data associated with a resource.
attribute in the "EA vals" block of data. Thus the sum of those sizes
equals the length of the "EA vals".
-Lock Value Block::
-A Lock Value Block (LVB) is included in the LDLM_ENQUEUE reply message
-when one of three things needs to be communicated back to the
-requester. The three alternatives are captured by the
-'ost_lvb' structure, the 'lov_mds_md' structure, and one other related
-to quotas (and not yet incorporated into this document). LDLM_ENQUEUE
-reply RPCs may include a zero length instance of an LVB.
-
-include::struct_ost_lvb.txt[]
-
-include::struct_lov_mds_md.txt[]
-
git://git.whamcloud.com / doc / protocol.git / blobdiff