Documentation: explain VM shared directories

Signed-off-by: Alyssa Ross <hi@alyssa.is>
Message-Id: <20221010232909.1953738-5-hi@alyssa.is>

2 files changed, 31 insertions, 0 deletions

diff --git a/Documentation/_sass/custom/custom.scss b/Documentation/_sass/custom/custom.scss
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@@ -0,0 +1,22 @@
+// SPDX-FileCopyrightText: 2022 Alyssa Ross <hi@alyssa.is>
+// SPDX-License-Identifier: MIT
+
+.main-content {
+    // Just the Docs puts titles next to definitions, rather than on
+    // the line before.  This makes the definitions too horizontally
+    // compressed.
+    dl {
+	display: block;
+    }
+    dt {
+	text-align: left;
+	font-weight: bold;
+
+	&::after {
+	    content: none;
+	}
+    }
+    dd {
+	margin-left: 2ch;
+    }
+}
diff --git a/Documentation/using-spectrum/creating-vms.adoc b/Documentation/using-spectrum/creating-vms.adoc
index 02cd3e6..f7560f0 100644
--- a/Documentation/using-spectrum/creating-vms.adoc
+++ b/Documentation/using-spectrum/creating-vms.adoc
@@ -20,6 +20,15 @@ blk:: A directory containing disk images (with file names ending in
 ".img") that will be provided to the guest as a virtio-blk device.
 Order is not guaranteed.  At least one image is *required*.
 
+shared-dirs:: A directory whose *subdirectories* each describe a
+directory to be shared with a VM.  The name of each subdirectory is
+used as the virtiofs tag, and the contents are as follows:
+
+  dir::: A symbolic link pointing to the directory to be shared with
+  the VM.  The directory must be on the
+  xref:../development/user-partition.adoc[user data partition].
+  *Required.*
+
 providers/net:: A directory containing a file named for each VM that
 should provide networking to this VM.  The contents of these files are
 ignored.