mirror of
https://github.com/xen-project/xen.git
synced 2026-10-28 02:01:24 +01:00
docs/libxl: Re-specify XENSTORE_DATA as EMULATOR_XENSTORE_DATA
The legacy "toolstack" record as implemented in libxl turns out not to be 32/64bit safe. As migration v2 has not shipped yet, take this opportunity to adjust the specification and fix the incompatibility. Libxl shall loose all knowledge of the old "toolstack" blob and use this EMULATOR_XENSTORE_DATA record instead. Compatibility shall be handled by the legacy conversion script. Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Acked-by: Ian Campbell <ian.campbell@citrix.com> Acked-by: Wei Liu <wei.liu2@citrix.com>
This commit is contained in:
Andrew Cooper authored and Ian Campbell committed
1 parent
2b8ba04cd1
commit
47801b0451
7 files changed
+160
-59
No files matched your search
@@ -90,8 +90,8 @@ i386, x86_64, or arm host.
|
||||
\clearpage
|
||||
|
||||
|
||||
Records
|
||||
=======
|
||||
Record Overview
|
||||
===============
|
||||
|
||||
A record has a record header, type specific data and a trailing footer. If
|
||||
`length` is not a multiple of 8, the body is padded with zeroes to align the
|
||||
@@ -113,7 +113,7 @@ type 0x00000000: END
|
||||
|
||||
0x00000001: LIBXC_CONTEXT
|
||||
|
||||
0x00000002: XENSTORE_DATA
|
||||
0x00000002: EMULATOR_XENSTORE_DATA
|
||||
|
||||
0x00000003: EMULATOR_CONTEXT
|
||||
|
||||
@@ -135,6 +135,38 @@ padding 0 to 7 octets of zeros to pad the whole record to a multiple
|
||||
|
||||
\clearpage
|
||||
|
||||
Emulator Records
|
||||
----------------
|
||||
|
||||
Several records are specifically for emulators, and have a common sub header.
|
||||
|
||||
0 1 2 3 4 5 6 7 octet
|
||||
+------------------------+------------------------+
|
||||
| emulator_id | index |
|
||||
+------------------------+------------------------+
|
||||
| record specific data |
|
||||
...
|
||||
+-------------------------------------------------+
|
||||
|
||||
--------------------------------------------------------------------
|
||||
Field Description
|
||||
------------ ---------------------------------------------------
|
||||
emulator_id 0x00000000: Unknown (In the case of a legacy stream)
|
||||
|
||||
0x00000001: Qemu Traditional
|
||||
|
||||
0x00000002: Qemu Upstream
|
||||
|
||||
0x00000003 - 0xFFFFFFFF: Reserved for future emulators.
|
||||
|
||||
index Index of this emulator for the domain.
|
||||
--------------------------------------------------------------------
|
||||
|
||||
\clearpage
|
||||
|
||||
Records
|
||||
=======
|
||||
|
||||
END
|
||||
----
|
||||
|
||||
@@ -163,17 +195,33 @@ The libxc context record contains no fields; its body_length is 0[^1].
|
||||
might write into the stream, especially for live migration where the quantity
|
||||
of data is partially proportional to the elapsed time.
|
||||
|
||||
XENSTORE\_DATA
|
||||
-------------
|
||||
EMULATOR\_XENSTORE\_DATA
|
||||
------------------------
|
||||
|
||||
A record containing xenstore key/value pairs of data.
|
||||
A set of xenstore key/value pairs for a specific emulator associated with the
|
||||
domain.
|
||||
|
||||
0 1 2 3 4 5 6 7 octet
|
||||
+-------------------------------------------------+
|
||||
| xenstore key/value pairs |
|
||||
+------------------------+------------------------+
|
||||
| emulator_id | index |
|
||||
+------------------------+------------------------+
|
||||
| xenstore key/value data |
|
||||
...
|
||||
+-------------------------------------------------+
|
||||
|
||||
Xenstore key/value data are encoded as a packed sequence of (key, value)
|
||||
tuples. Each (key, value) tuple is a packed pair of NUL terminated octets,
|
||||
conforming to xenstore protocol character encoding (keys strictly as
|
||||
alphanumeric ASCII and `-/_@`, values expected to be human-readable ASCII).
|
||||
|
||||
Keys shall be relative to to the device models xenstore tree for the new
|
||||
domain. At the time of writing, keys are relative to the path
|
||||
|
||||
> `/local/domain/$dm_domid/device-model/$domid/`
|
||||
|
||||
although this path is free to change moving forward, thus should not be
|
||||
assumed.
|
||||
|
||||
EMULATOR\_CONTEXT
|
||||
----------------
|
||||
|
||||
@@ -187,22 +235,8 @@ A context blob for a specific emulator associated with the domain.
|
||||
...
|
||||
+-------------------------------------------------+
|
||||
|
||||
--------------------------------------------------------------------
|
||||
Field Description
|
||||
------------ ---------------------------------------------------
|
||||
emulator_id 0x00000000: Unknown (In the case of a legacy stream)
|
||||
|
||||
0x00000001: Qemu Traditional
|
||||
|
||||
0x00000002: Qemu Upstream
|
||||
|
||||
0x00000003 - 0xFFFFFFFF: Reserved for future emulators.
|
||||
|
||||
index Index of this emulator for the domain, if multiple
|
||||
emulators are in use.
|
||||
|
||||
emulator_ctx Emulator context blob.
|
||||
--------------------------------------------------------------------
|
||||
The *emulator_ctx* is a binary blob interpreted by the emulator identified by
|
||||
*emulator_id*. Its format is unspecified.
|
||||
|
||||
CHECKPOINT\_END
|
||||
---------------
|
||||
|
||||