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-rw-r--r-- | content.tex | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/content.tex b/content.tex index 4525975..83d1afd 100644 --- a/content.tex +++ b/content.tex @@ -404,7 +404,7 @@ struct virtq_desc { \end{lstlisting} The number of descriptors in the table is defined by the queue size -for this virtqueue. +for this virtqueue: this is the maximum possible descriptor chain length. \begin{note} The legacy \hyperref[intro:Virtio PCI Draft]{[Virtio PCI Draft]} @@ -456,6 +456,9 @@ VIRTIO_F_INDIRECT_DESC feature was negotiated. The driver MUST NOT set the VIRTQ_DESC_F_INDIRECT flag within an indirect descriptor (ie. only one table per descriptor). +A driver MUST NOT create a descriptor chain longer than the Queue Size of +the device. + \devicenormative{\paragraph}{Indirect Descriptors}{Basic Facilities of a Virtio Device / Virtqueues / The Virtqueue Descriptor Table / Indirect Descriptors} The device MUST ignore the write-only flag (\field{flags}\&VIRTQ_DESC_F_WRITE) in the descriptor that refers to an indirect table. |