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| -rw-r--r-- | content.tex | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/content.tex b/content.tex index 05cbac8..907ea5a 100644 --- a/content.tex +++ b/content.tex @@ -843,7 +843,7 @@ MUST access each field using the “natural” access method (i.e. 32-bit access \subsection{Virtio Structure PCI Capabilities}\label{sec:Virtio Transport Options / Virtio Over PCI Bus / Virtio Structure PCI Capabilities} -The virtio device configuration layout includes a common configuration header, notification area, ISR status area and a device-specific configuration area. +The virtio device configuration layout includes a common configuration structure, the notification area, ISR status register and a device-specific configuration registers. Each structure can be mapped by a Base Address register (BAR) belonging to the function, or accessed via the special VIRTIO_PCI_CAP_PCI_CFG field in the PCI configuration space. @@ -1145,18 +1145,18 @@ registers in a legacy configuration structure in BAR0 in the first I/O region of the PCI device, as documented below. There may be different widths of accesses to the I/O region; the -“natural” access method for each field in the virtio header must be +“natural” access method for each field in the virtio common configuration structure must be used (i.e. 32-bit accesses for 32-bit fields, etc), but when accessed through the legacy interface the device-specific region can be accessed using any width accesses, and should obtain the same results. -Note that this is possible because while the virtio header is PCI +Note that this is possible because while the virtio common configuration structure is PCI (i.e. little) endian, when using the legacy interface the device-specific region is encoded in the native endian of the guest (where such distinction is applicable). -When used through the legacy interface, the virtio header looks as follows: +When used through the legacy interface, the virtio common configuration structure looks as follows: \begin{tabularx}{\textwidth}{ |X||X|X|X|X|X|X|X|X| } \hline @@ -1184,7 +1184,7 @@ Purpose (MSI-X) & \field{config_msix_vector} & \field{queue_msix_vector} \\ \end{tabular} Note: When MSI-X capability is enabled, device specific configuration starts at -byte offset 24 in virtio header structure. When MSI-X capability is not +byte offset 24 in virtio common configuration structure structure. When MSI-X capability is not enabled, device specific configuration starts at byte offset 20 in virtio header. ie. once you enable MSI-X on the device, the other fields move. If you turn it off again, they move back! |