[xen stable-4.15] docs/misc: xenstored: Re-instate and tweak the documentation for XS_RESUME

[patchbot@xxxxxxx]

commit 7087b61fc4bfc19367d39f48649cfe0837ee45e2
Author:     Julien Grall <jgrall@xxxxxxxxxx>
AuthorDate: Thu Mar 25 17:46:30 2021 +0000
Commit:     Julien Grall <jgrall@xxxxxxxxxx>
CommitDate: Fri Mar 26 12:13:17 2021 +0000

    docs/misc: xenstored: Re-instate and tweak the documentation for XS_RESUME
    
    Commit 13dd372834a4 removed the documentation for XS_RESUME, however
    this command is still implemented (at least in C Xenstored) and used by
    libxl when resuming a domain.
    
    So re-instate the documentation for the XS_RESUME. Take the opportunity
    to update it as there is a user of the command.
    
    Fixes: 13dd372834a4 ("docs/designs: re-work the xenstore migration 
document...")
    Signed-off-by: Julien Grall <jgrall@xxxxxxxxxx>
    Reviewed-by: Paul Durrant <paul@xxxxxxx>
    Reviewed-by: Juergen Gross <jgross@xxxxxxxx>
    Reviewed-by: Ian Jackson <iwj@xxxxxxxxxxxxxx>
    Release-Acked-by: Ian Jackson <iwj@xxxxxxxxxxxxxx>
    (cherry picked from commit 03bee3fd475cb755572dd21214daecf9a77a6bb4)
---
 docs/misc/xenstore.txt | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/docs/misc/xenstore.txt b/docs/misc/xenstore.txt
index 1480742330..334dc8b6fd 100644
--- a/docs/misc/xenstore.txt
+++ b/docs/misc/xenstore.txt
@@ -294,6 +294,22 @@ IS_DOMAIN_INTRODUCED       <domid>|                T| or F|
        ie, if INTRODUCE for the domain has not yet been followed by
        domain destruction or explicit RELEASE.
 
+RESUME                 <domid>|
+
+       Arranges that @releaseDomain events will once more be
+       generated when the domain becomes shut down.  This might have
+       to be used if a domain were to be shut down (generating one
+       @releaseDomain) and then subsequently restarted, since the
+       state-sensitive algorithm in xenstored will not otherwise send
+       further watch event notifications if the domain were to be
+       shut down again.
+
+       This command will be issued in place such as resume because
+       Xen will "shutdown" the domain on suspend.
+
+       xenstored prevents the use of RESUME other than by dom0.
+
+
 SET_TARGET             <domid>|<tdomid>|
        Notifies xenstored that domain <domid> is targeting domain
        <tdomid>. This grants domain <domid> full access to paths
--
generated by git-patchbot for /home/xen/git/xen.git#stable-4.15