* [PATCH RFC] virtio-spec: flexible configuration layout
From: Michael S. Tsirkin @ 2011-11-08 21:40 UTC (permalink / raw)
To: Rusty Russell
Cc: Krishna Kumar, kvm, Pawel Moll, Wang Sheng-Hui,
Alexey Kardashevskiy, lkml - Kernel Mailing List, virtualization,
Christian Borntraeger, Sasha Levin, Amit Shah, avi
In-Reply-To: <20111102233110.GA20289@redhat.com>
Here's a spec change documenting what my C patch does
(almost - I tweaked the layout a bit, but the idea is the same).
Some more cleanups are needed but I thought I'd send it
for early flames/comments.
The idea is simple: we split functionally unrelated
register groups to independent structures, and let
the device place is anywhere using a capability
in PCI configuration space.
It can then go into MMIO space which is cheaper than PIO.
A legacy portion of the configuration is mirrored
in the first BAR, to keep legacy drivers working.
Any new fields can be added in existing structures
at the end, so they won't affect legacy.
Alternatively we can add new structures with new
structure IDs, pointed to from PCI configuration space.
As we don't yet have devices or drivers with 64 bit features,
I decided we don't need high feature bits in legacy space.
This also frees up feature bit 31 as we don't need it
to enable high feature bits anymore.
As this solves the dynamic placement of MSIX vectors
and high feature bits,
I thought it's easier to just reserve space for that
programming than give it a separate structure. This
can be changed by a patch on top.
Note that data path is split from configuration.
PDF will follow.
----
diff --git a/virtio-spec.lyx b/virtio-spec.lyx
index 6426f8f..5aec38c 100644
--- a/virtio-spec.lyx
+++ b/virtio-spec.lyx
@@ -56,6 +56,7 @@
\html_math_output 0
\html_css_as_file 0
\html_be_strict false
+\author 1986246365 "Michael S. Tsirkin"
\end_header
\begin_body
@@ -570,7 +571,34 @@ Device Configuration
\end_layout
\begin_layout Standard
-To configure the device, we use the first I/O region of the PCI device.
+To configure the device, we
+\change_inserted 1986246365 1320783354
+use I/O and/or memory regions of the PCI device.
+ These contain the virtio header registers, the notification register, the
+ ISR status register and device specific registers, as specified by Virtio
+ Structure PCI Capabilities
+\begin_inset Foot
+status open
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320787659
+For backwards compatibility, devices should present part of these configuration
+ registers in a legacy configuration structure in the first I/O region of
+ the PCI device
+\change_unchanged
+
+\end_layout
+
+\end_inset
+
+.
+\end_layout
+
+\begin_layout Standard
+
+\change_deleted 1986246365 1320766512
+use the first I/O region of the PCI device.
This contains a
\emph on
virtio header
@@ -578,6 +606,8 @@ virtio header
followed by a
\emph on
device-specific region.
+\change_unchanged
+
\end_layout
\begin_layout Standard
@@ -595,9 +625,23 @@ natural
\end_layout
\begin_layout Standard
-Note that this is possible because while the virtio header is PCI (i.e.
- little) endian, the device-specific region is encoded in the native endian
- of the guest (where such distinction is applicable).
+Note that this is possible because while the virtio header
+\change_inserted 1986246365 1320767249
+, notification and ISR status are
+\change_deleted 1986246365 1320767251
+ is
+\change_unchanged
+ PCI (i.e.
+ little) endian, the device-specific
+\change_deleted 1986246365 1320767335
+ region is
+\change_inserted 1986246365 1320767337
+registers are
+\change_unchanged
+ encoded in the native endian of the guest (where such distinction is applicable
+).
+\change_inserted 1986246365 1320767660
+
\end_layout
\begin_layout Subsection
@@ -635,51 +679,2954 @@ Device-specific setup, including reading the Device Feature Bits, discovery
writing the virtio configuration space.
\end_layout
-\begin_layout Enumerate
-The subset of Device Feature Bits understood by the driver is written to
- the device.
+\begin_layout Enumerate
+The subset of Device Feature Bits understood by the driver is written to
+ the device.
+\end_layout
+
+\begin_layout Enumerate
+The DRIVER_OK status bit is set.
+\end_layout
+
+\begin_layout Enumerate
+The device can now be used (ie.
+ buffers added to the virtqueues)
+\begin_inset Foot
+status open
+
+\begin_layout Plain Layout
+Historically, drivers have used the device before steps 5 and 6.
+ This is only allowed if the driver does not use any features which would
+ alter this early use of the device.
+\end_layout
+
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+If any of these steps go irrecoverably wrong, the guest should set the FAILED
+ status bit to indicate that it has given up on the device (it can reset
+ the device later to restart if desired).
+\end_layout
+
+\begin_layout Standard
+We now cover the fields required for general setup in detail.
+\change_inserted 1986246365 1320766663
+
+\end_layout
+
+\begin_layout Subsection
+
+\change_inserted 1986246365 1320781584
+Virtio Structure PCI Capability
+\end_layout
+
+\begin_layout Standard
+
+\change_inserted 1986246365 1320781061
+Virtio configuration layout includes virtio configuration header, notification
+ and ISR status and device configuration structures.
+ Each structure is mapped by a Base Address register (BAR) belonging to
+ the function, located beginning at 10h in Configuration Space.
+
+\emph on
+Structure ID
+\emph default
+indentifies the structure
+\emph on
+, Size
+\emph default
+ indicates the structure size, in bytes, a
+\emph on
+BAR Indicator register (BIR)
+\emph default
+ indicates which BAR, and
+\emph on
+Offset
+\emph default
+ indicates where the structure begins relative to the base address associated
+ with the BAR.
+ The BAR is permitted to be either 32-bit or 64-bit, it can map Memory Space
+ or I/O Space.
+\end_layout
+
+\begin_layout Standard
+
+\change_inserted 1986246365 1320781133
+These registers are specified using vendor-specific PCI capability located
+ on capability list in PCI configuration space of the device.
+ This virtio structure capability uses little-endian format; all bits are
+ read-only:
+\end_layout
+
+\begin_layout Standard
+
+\change_inserted 1986246365 1320772579
+\begin_inset Tabular
+<lyxtabular version="3" rows="4" columns="34">
+<features tabularvalignment="middle">
+<column alignment="center" valignment="top" width="0pt">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0pt">
+<row>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771774
+Bit
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771777
+31
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771779
+30
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771781
+29
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771783
+28
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771786
+27
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771810
+26
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771813
+25
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771815
+24
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771817
+23
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771819
+22
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771821
+21
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771823
+20
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771825
+19
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771829
+18
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771831
+17
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771833
+16
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771835
+15
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771840
+14
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771841
+13
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771843
+12
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771845
+11
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771847
+10
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771850
+9
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771852
+8
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771854
+7
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771856
+6
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771858
+5
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771859
+4
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771861
+3
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771862
+2
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771864
+1
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771888
+0
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320771997
+Offset
+\end_layout
+
+\end_inset
+</cell>
+</row>
+<row>
+<cell alignment="center" valignment="top" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="1" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320781029
+Structure ID
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="1" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320772123
+Capability Length = 12
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="1" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320772095
+Next Capability Pointer
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="1" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320772055
+Capability ID = 9
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320772004
+0
+\end_layout
+
+\end_inset
+</cell>
+</row>
+<row>
+<cell alignment="center" valignment="top" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="1" alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320772549
+Size
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="1" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320779698
+BAR Indicator Register
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320772007
+4
+\end_layout
+
+\end_inset
+</cell>
+</row>
+<row>
+<cell alignment="center" valignment="top" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="1" alignment="center" valignment="top" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320772540
+Offset
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell multicolumn="2" alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320772011
+8
+\end_layout
+
+\end_inset
+</cell>
+</row>
+</lyxtabular>
+
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+
+\change_inserted 1986246365 1320779667
+Purpose:
+\end_layout
+
+\begin_layout Standard
+
+\change_inserted 1986246365 1320780912
+
+\emph on
+Capability ID
+\emph default
+,
+\emph on
+Next Capability Pointer
+\emph default
+,
+\emph on
+Capability Length
+\emph default
+ - these fields are specified by PCI local bus specification, Rev 3.0
+\end_layout
+
+\begin_layout Standard
+
+\change_inserted 1986246365 1320785073
+
+\emph on
+Structure ID
+\emph default
+ - identifies the structure mapped.
+ If an ID representing a specific structure is absent, the structure is
+ located in the legacy virtio configuration in the first PCI BAR.
+\end_layout
+
+\begin_layout Standard
+
+\change_inserted 1986246365 1320782689
+
+\emph on
+Size
+\emph default
+ - size of the structure mapped.
+ This size might include padding, or fields unused by the driver.
+ Drivers are also recommended to only map part of configuration structure
+ large enough for device operation.
+ For example, a future device might present a large structure size of several
+ MBytes.
+ As current devices never utilize structures larger than 4KBytes in size,
+ driver can limit the mapped structure size to e.g.
+ 4KBytes to allow forward compatibility with such devices without loss of
+ functionality and without wasting resources.
+\change_unchanged
+
+\end_layout
+
+\begin_layout Standard
+
+\change_inserted 1986246365 1320781965
+
+\emph on
+BAR Indicator Register
+\emph default
+ - Indicates which one of the BAR registers, located beginning at 10h in
+ Configuration Space, is used to map the structure into Memory or I/O Space.
+ Legal values are 0 - 5.
+ BAR offset is calculated as
+\emph on
+BAR
+\emph default
+ = 10h + 4 *
+\emph on
+BIR.
+\end_layout
+
+\begin_layout Standard
+
+\change_inserted 1986246365 1320781002
+
+\emph on
+Offset
+\emph default
+ - Used as an offset from the address contained by one of the function’s
+ Base Address registers to point to the base of the structure.
+ Depending on the structure, the lower bits are masked off (set to zero)
+ by software to form an aligned offset.
+\end_layout
+
+\begin_layout Standard
+
+\change_inserted 1986246365 1320785098
+A single device has multiple virtio capabilities on the PCI capability linked-li
+st.
+ To locate a specific register, driver scans the PCI capability list looking
+ for capabilities using the vendor specific
+\emph on
+Capability ID
+\emph default
+, that is
+\emph on
+Capability ID
+\emph default
+ value
+\emph on
+9
+\emph default
+, according to the PCI spec.
+ For each capability, it verifies that the
+\emph on
+Capability Length
+\emph default
+ field matches the expected value (12) - if it doesn't, this indicates a
+ layout change, which causes driver to ignore the specific PCI capability
+ and proceed to the next PCI capability in the list.
+ Next,
+\emph on
+ Structure ID
+\emph default
+ single-byte field is read at offset 3.
+ Unrecognized
+\emph on
+Structure ID
+\emph default
+ values are ignored.
+ Low bits in the
+\emph on
+Offset
+\emph default
+ register are masked to match alignment requirements, if any.
+ Device drivers are recommended to sanity check
+\emph on
+BIR
+\emph default
+,
+\emph on
+Offset
+\emph default
+, and
+\emph on
+Size
+\emph default
+ fields, ignoring the capability or failing gracefully on error.
+ Drivers are also recommended to only map part of configuration structure
+ large enough for device operation.
+\end_layout
+
+\begin_layout Standard
+
+\change_inserted 1986246365 1320786035
+For backwards compatibility, devices should also present legacy configuration
+ space in the first I/O region of the PCI device, mirroring virtio configuration
+ structures in this space.
+ Drivers should fall back on this legacy structure if a specific Virtio
+ Structure capability is missing in the PCI capability list.
+ However, devices are not required to map the whole configuration structure
+ in legacy space - only the initial segment expected by legacy drivers needs
+ to be mapped.
+ The minimal size of such legacy segment size, for each structure, is listed
+ below.
+ Drivers are discouraged from using legacy space if a specific Structure
+ ID is present; this is to allow deprecating the legacy space in the future.
+\end_layout
+
+\begin_layout Standard
+
+\change_inserted 1986246365 1320786428
+Below is the list of supported Virtio structures, including Structure ID,
+ offset alignment, and where it can be located in the legacy configuration
+ space.
+ Note that legacy space layout changes as the MSI-X capability is enabled
+ and disabled
+\begin_inset Foot
+status open
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786428
+ie.
+ once you enable MSI-X on the device, the other fields move.
+ If you turn it off again, they move back!
+\end_layout
+
+\end_inset
+
+.
+\end_layout
+
+\begin_layout Standard
+
+\change_inserted 1986246365 1320786868
+\begin_inset Tabular
+<lyxtabular version="3" rows="5" columns="6">
+<features tabularvalignment="middle">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<column alignment="center" valignment="top" width="0">
+<row>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+Structure
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+ID
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+Alignment
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786921
+Minimal Size
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320785821
+Offset in legacy space
+\change_deleted 1986246365 1320785817
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786926
+Minimal Size in legacy space
+\end_layout
+
+\end_inset
+</cell>
+</row>
+<row>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320785855
+Virtio Header
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320785860
+0x1
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786157
+4 bytes
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786225
+28 bytes
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786145
+0
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786236
+24 bytes if MSI-X is enabled, 20 if disabled
+\end_layout
+
+\end_inset
+</cell>
+</row>
+<row>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786188
+Queue Notify
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786191
+0x2
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786267
+2 bytes
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786228
+2 bytes
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786505
+16 bytes
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786303
+2 bytes
+\end_layout
+
+\end_inset
+</cell>
+</row>
+<row>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786878
+ISR Status
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786260
+0x3
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786270
+1 byte
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786273
+1 byte
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786534
+19 bytes
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786306
+1 byte
+\end_layout
+
+\end_inset
+</cell>
+</row>
+<row>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786847
+Device Header
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786474
+0x4
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786477
+1 byte
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786487
+Device specific
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786513
+24 bytes if MSI-X is enabled, 20 if disabled
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786492
+Device specific
+\end_layout
+
+\end_inset
+</cell>
+</row>
+</lyxtabular>
+
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+
+\change_inserted 1986246365 1320786973
+Drivers should assume that each structure size can be extended in the future.
+\end_layout
+
+\begin_layout Standard
+
+\change_inserted 1986246365 1320787003
+Queue Notify and ISR status are single-field registers.
+ Device Header has device specific structure.
+ Virtio Header structure is documented below.
+\change_unchanged
+
+\end_layout
+
+\begin_layout Subsection
+Virtio Header
+\end_layout
+
+\begin_layout Standard
+The virtio header looks as follows:
+\end_layout
+
+\begin_layout Standard
+\begin_inset Tabular
+<lyxtabular version="3" rows="4" columns="9">
+<features tabularvalignment="middle">
+<column alignment="left" valignment="top" width="0">
+<column alignment="left" valignment="top" width="0">
+<column alignment="left" valignment="top" width="0">
+<column alignment="left" valignment="top" width="0">
+<column alignment="left" valignment="top" width="0">
+<column alignment="left" valignment="top" width="0">
+<column alignment="left" valignment="top" width="0">
+<column alignment="left" valignment="top" width="0">
+<column alignment="left" valignment="top" width="0">
+<row>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+Bits
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+32
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+32
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+32
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+16
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+16
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+16
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+8
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+8
+\end_layout
+
+\end_inset
+</cell>
+</row>
+<row>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+Read/Write
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+R
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+R+W
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+R+W
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+R
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+R+W
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+R+W
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+R+W
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+R
+\end_layout
+
+\end_inset
+</cell>
+</row>
+<row>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+Purpose
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\size footnotesize
+Device
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\size footnotesize
+Guest
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\size footnotesize
+Queue
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\size footnotesize
+Queue
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\size footnotesize
+Queue
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786386
+
+\size footnotesize
+Reserved
+\change_deleted 1986246365 1320786378
+Queue
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\size footnotesize
+Device
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786393
+
+\size footnotesize
+Reserved
+\change_deleted 1986246365 1320786390
+ISR
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+</row>
+<row>
+<cell alignment="center" valignment="top" bottomline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\size footnotesize
+Features bits 0:31
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\size footnotesize
+Features bits 0:31
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\size footnotesize
+Address
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\size footnotesize
+Size
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\size footnotesize
+Select
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_deleted 1986246365 1320786378
+
+\size footnotesize
+Notify
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\size footnotesize
+Status
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" bottomline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\change_deleted 1986246365 1320786388
+
+\size footnotesize
+Status
+\change_unchanged
+
+\end_layout
+
+\end_inset
+</cell>
+</row>
+</lyxtabular>
+
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+
+\change_deleted 1986246365 1320786398
+If MSI-X is enabled for the device, two additional fields immediately follow
+ this header:
+\begin_inset Foot
+status open
+
+\begin_layout Plain Layout
+ie.
+ once you enable MSI-X on the device, the other fields move.
+ If you turn it off again, they move back!
+\end_layout
+
+\end_inset
+
+
+\change_unchanged
+
+\end_layout
+
+\begin_layout Standard
+\begin_inset Tabular
+<lyxtabular version="3" rows="4" columns="3">
+<features tabularvalignment="middle">
+<column alignment="left" valignment="top" width="0">
+<column alignment="left" valignment="top" width="0">
+<column alignment="left" valignment="top" width="0">
+<row>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+Bits
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+16
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+16
+\end_layout
+
+\end_inset
+</cell>
+</row>
+<row>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+Read/Write
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+R+W
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+R+W
+\end_layout
+
+\end_inset
+</cell>
+</row>
+<row>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+Purpose
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\size footnotesize
+Configuration
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\size footnotesize
+Queue
+\end_layout
+
+\end_inset
+</cell>
+</row>
+<row>
+<cell alignment="center" valignment="top" bottomline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+(MSI-X)
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\size footnotesize
+Vector
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" bottomline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\size footnotesize
+Vector
+\end_layout
+
+\end_inset
+</cell>
+</row>
+</lyxtabular>
+
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+
+\change_deleted 1986246365 1320786816
+Finally, if feature bits (VIRTIO_F_FEATURES_HI)
+\change_unchanged
+ this is immediately followed by two additional fields:
+\end_layout
+
+\begin_layout Standard
+\begin_inset Tabular
+<lyxtabular version="3" rows="4" columns="3">
+<features tabularvalignment="middle">
+<column alignment="left" valignment="top" width="0">
+<column alignment="left" valignment="top" width="0">
+<column alignment="left" valignment="top" width="0">
+<row>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+Bits
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+32
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+32
+\end_layout
+
+\end_inset
+</cell>
+</row>
+<row>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+Read/Write
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+R
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+R+W
+\end_layout
+
+\end_inset
+</cell>
+</row>
+<row>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+Purpose
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\size footnotesize
+Device
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\size footnotesize
+Guest
+\end_layout
+
+\end_inset
+</cell>
+</row>
+<row>
+<cell alignment="center" valignment="top" bottomline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\size footnotesize
+Features bits 32:63
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\size footnotesize
+Features bits 32:63
+\end_layout
+
+\end_inset
+</cell>
+</row>
+</lyxtabular>
+
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+
+\change_deleted 1986246365 1320786783
+Immediately following these general headers, there may be device-specific
+ headers:
+\end_layout
+
+\begin_layout Standard
+
+\change_deleted 1986246365 1320786783
+\begin_inset Tabular
+<lyxtabular version="3" rows="4" columns="2">
+<features tabularvalignment="middle">
+<column alignment="left" valignment="top" width="0">
+<column alignment="left" valignment="top" width="0">
+<row>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+Bits
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+Device Specific
+\end_layout
+
+\end_inset
+</cell>
+</row>
+<row>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+Read/Write
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+Device Specific
+\end_layout
+
+\end_inset
+</cell>
+</row>
+<row>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+Purpose
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\size footnotesize
+Device Specific...
\end_layout
-\begin_layout Enumerate
-The DRIVER_OK status bit is set.
+\end_inset
+</cell>
+</row>
+<row>
+<cell alignment="center" valignment="top" bottomline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
\end_layout
-\begin_layout Enumerate
-The device can now be used (ie.
- buffers added to the virtqueues)
-\begin_inset Foot
-status open
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" bottomline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
\begin_layout Plain Layout
-Historically, drivers have used the device before steps 5 and 6.
- This is only allowed if the driver does not use any features which would
- alter this early use of the device.
+
\end_layout
\end_inset
+</cell>
+</row>
+</lyxtabular>
+\end_inset
-\end_layout
-\begin_layout Standard
-If any of these steps go irrecoverably wrong, the guest should set the FAILED
- status bit to indicate that it has given up on the device (it can reset
- the device later to restart if desired).
-\end_layout
+\change_inserted 1986246365 1320784618
-\begin_layout Standard
-We now cover the fields required for general setup in detail.
\end_layout
\begin_layout Subsection
-Virtio Header
+
+\change_inserted 1986246365 1320786351
+Legacy Virtio Header
\end_layout
\begin_layout Standard
-The virtio header looks as follows:
+
+\change_inserted 1986246365 1320786351
+For reference, the legacy virtio header looks as follows; one observes that
+ most register offsets match the new virtio header, to make compatibility
+ easier:
\end_layout
\begin_layout Standard
+
+\change_inserted 1986246365 1320786351
\begin_inset Tabular
<lyxtabular version="3" rows="4" columns="9">
<features tabularvalignment="middle">
@@ -697,6 +3644,8 @@ The virtio header looks as follows:
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
Bits
\end_layout
@@ -706,6 +3655,8 @@ Bits
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
32
\end_layout
@@ -715,6 +3666,8 @@ Bits
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
32
\end_layout
@@ -724,6 +3677,8 @@ Bits
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
32
\end_layout
@@ -733,6 +3688,8 @@ Bits
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
16
\end_layout
@@ -742,6 +3699,8 @@ Bits
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
16
\end_layout
@@ -751,6 +3710,8 @@ Bits
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
16
\end_layout
@@ -760,6 +3721,8 @@ Bits
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
8
\end_layout
@@ -769,6 +3732,8 @@ Bits
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
8
\end_layout
@@ -780,6 +3745,8 @@ Bits
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
Read/Write
\end_layout
@@ -789,6 +3756,8 @@ Read/Write
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
R
\end_layout
@@ -798,6 +3767,8 @@ R
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
R+W
\end_layout
@@ -807,6 +3778,8 @@ R+W
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
R+W
\end_layout
@@ -816,6 +3789,8 @@ R+W
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
R
\end_layout
@@ -825,6 +3800,8 @@ R
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
R+W
\end_layout
@@ -834,6 +3811,8 @@ R+W
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
R+W
\end_layout
@@ -843,6 +3822,8 @@ R+W
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
R+W
\end_layout
@@ -852,6 +3833,8 @@ R+W
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
R
\end_layout
@@ -863,6 +3846,8 @@ R
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
Purpose
\end_layout
@@ -873,6 +3858,8 @@ Purpose
\begin_layout Plain Layout
+\change_inserted 1986246365 1320786351
+
\size footnotesize
Device
\end_layout
@@ -884,6 +3871,8 @@ Device
\begin_layout Plain Layout
+\change_inserted 1986246365 1320786351
+
\size footnotesize
Guest
\end_layout
@@ -895,6 +3884,8 @@ Guest
\begin_layout Plain Layout
+\change_inserted 1986246365 1320786351
+
\size footnotesize
Queue
\end_layout
@@ -906,6 +3897,8 @@ Queue
\begin_layout Plain Layout
+\change_inserted 1986246365 1320786351
+
\size footnotesize
Queue
\end_layout
@@ -917,6 +3910,8 @@ Queue
\begin_layout Plain Layout
+\change_inserted 1986246365 1320786351
+
\size footnotesize
Queue
\end_layout
@@ -928,6 +3923,8 @@ Queue
\begin_layout Plain Layout
+\change_inserted 1986246365 1320786351
+
\size footnotesize
Queue
\end_layout
@@ -939,6 +3936,8 @@ Queue
\begin_layout Plain Layout
+\change_inserted 1986246365 1320786351
+
\size footnotesize
Device
\end_layout
@@ -950,6 +3949,8 @@ Device
\begin_layout Plain Layout
+\change_inserted 1986246365 1320786351
+
\size footnotesize
ISR
\end_layout
@@ -963,6 +3964,8 @@ ISR
\begin_layout Plain Layout
+\change_inserted 1986246365 1320786351
+
\end_layout
\end_inset
@@ -972,6 +3975,8 @@ ISR
\begin_layout Plain Layout
+\change_inserted 1986246365 1320786351
+
\size footnotesize
Features bits 0:31
\end_layout
@@ -983,6 +3988,8 @@ Features bits 0:31
\begin_layout Plain Layout
+\change_inserted 1986246365 1320786351
+
\size footnotesize
Features bits 0:31
\end_layout
@@ -994,6 +4001,8 @@ Features bits 0:31
\begin_layout Plain Layout
+\change_inserted 1986246365 1320786351
+
\size footnotesize
Address
\end_layout
@@ -1005,6 +4014,8 @@ Address
\begin_layout Plain Layout
+\change_inserted 1986246365 1320786351
+
\size footnotesize
Size
\end_layout
@@ -1016,6 +4027,8 @@ Size
\begin_layout Plain Layout
+\change_inserted 1986246365 1320786351
+
\size footnotesize
Select
\end_layout
@@ -1027,6 +4040,8 @@ Select
\begin_layout Plain Layout
+\change_inserted 1986246365 1320786351
+
\size footnotesize
Notify
\end_layout
@@ -1038,6 +4053,8 @@ Notify
\begin_layout Plain Layout
+\change_inserted 1986246365 1320786351
+
\size footnotesize
Status
\end_layout
@@ -1049,6 +4066,8 @@ Status
\begin_layout Plain Layout
+\change_inserted 1986246365 1320786351
+
\size footnotesize
Status
\end_layout
@@ -1064,12 +4083,16 @@ Status
\end_layout
\begin_layout Standard
+
+\change_inserted 1986246365 1320786351
If MSI-X is enabled for the device, two additional fields immediately follow
this header:
\begin_inset Foot
status collapsed
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
ie.
once you enable MSI-X on the device, the other fields move.
If you turn it off again, they move back!
@@ -1081,6 +4104,8 @@ ie.
\end_layout
\begin_layout Standard
+
+\change_inserted 1986246365 1320786351
\begin_inset Tabular
<lyxtabular version="3" rows="4" columns="3">
<features tabularvalignment="middle">
@@ -1092,6 +4117,8 @@ ie.
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
Bits
\end_layout
@@ -1101,6 +4128,8 @@ Bits
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
16
\end_layout
@@ -1110,6 +4139,8 @@ Bits
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
16
\end_layout
@@ -1121,6 +4152,8 @@ Bits
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
Read/Write
\end_layout
@@ -1130,6 +4163,8 @@ Read/Write
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
R+W
\end_layout
@@ -1139,6 +4174,8 @@ R+W
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
R+W
\end_layout
@@ -1150,6 +4187,8 @@ R+W
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
Purpose
\end_layout
@@ -1160,6 +4199,8 @@ Purpose
\begin_layout Plain Layout
+\change_inserted 1986246365 1320786351
+
\size footnotesize
Configuration
\end_layout
@@ -1171,6 +4212,8 @@ Configuration
\begin_layout Plain Layout
+\change_inserted 1986246365 1320786351
+
\size footnotesize
Queue
\end_layout
@@ -1183,6 +4226,8 @@ Queue
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
(MSI-X)
\end_layout
@@ -1193,16 +4238,7 @@ Queue
\begin_layout Plain Layout
-\size footnotesize
-Vector
-\end_layout
-
-\end_inset
-</cell>
-<cell alignment="center" valignment="top" bottomline="true" leftline="true" rightline="true" usebox="none">
-\begin_inset Text
-
-\begin_layout Plain Layout
+\change_inserted 1986246365 1320786351
\size footnotesize
Vector
@@ -1210,145 +4246,15 @@ Vector
\end_inset
</cell>
-</row>
-</lyxtabular>
-
-\end_inset
-
-
-\end_layout
-
-\begin_layout Standard
-Finally, if feature bits (VIRTIO_F_FEATURES_HI) this is immediately followed
- by two additional fields:
-\end_layout
-
-\begin_layout Standard
-\begin_inset Tabular
-<lyxtabular version="3" rows="4" columns="3">
-<features tabularvalignment="middle">
-<column alignment="left" valignment="top" width="0">
-<column alignment="left" valignment="top" width="0">
-<column alignment="left" valignment="top" width="0">
-<row>
-<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
-\begin_inset Text
-
-\begin_layout Plain Layout
-Bits
-\end_layout
-
-\end_inset
-</cell>
-<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
-\begin_inset Text
-
-\begin_layout Plain Layout
-32
-\end_layout
-
-\end_inset
-</cell>
-<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
-\begin_inset Text
-
-\begin_layout Plain Layout
-32
-\end_layout
-
-\end_inset
-</cell>
-</row>
-<row>
-<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
-\begin_inset Text
-
-\begin_layout Plain Layout
-Read/Write
-\end_layout
-
-\end_inset
-</cell>
-<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
-\begin_inset Text
-
-\begin_layout Plain Layout
-R
-\end_layout
-
-\end_inset
-</cell>
-<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
-\begin_inset Text
-
-\begin_layout Plain Layout
-R+W
-\end_layout
-
-\end_inset
-</cell>
-</row>
-<row>
-<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
-\begin_inset Text
-
-\begin_layout Plain Layout
-Purpose
-\end_layout
-
-\end_inset
-</cell>
-<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
-\begin_inset Text
-
-\begin_layout Plain Layout
-
-\size footnotesize
-Device
-\end_layout
-
-\end_inset
-</cell>
-<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
-\begin_inset Text
-
-\begin_layout Plain Layout
-
-\size footnotesize
-Guest
-\end_layout
-
-\end_inset
-</cell>
-</row>
-<row>
<cell alignment="center" valignment="top" bottomline="true" leftline="true" rightline="true" usebox="none">
\begin_inset Text
\begin_layout Plain Layout
-\end_layout
-
-\end_inset
-</cell>
-<cell alignment="center" valignment="top" bottomline="true" leftline="true" usebox="none">
-\begin_inset Text
-
-\begin_layout Plain Layout
-
-\size footnotesize
-Features bits 32:63
-\end_layout
-
-\end_inset
-</cell>
-<cell alignment="center" valignment="top" bottomline="true" leftline="true" usebox="none">
-\begin_inset Text
-
-\begin_layout Plain Layout
+\change_inserted 1986246365 1320786351
\size footnotesize
-Features bits 32:63
+Vector
\end_layout
\end_inset
@@ -1362,11 +4268,15 @@ Features bits 32:63
\end_layout
\begin_layout Standard
-Immediately following these general headers, there may be device-specific
+
+\change_inserted 1986246365 1320786351
+Immediately following these general headers, there may be legacy device-specific
headers:
\end_layout
\begin_layout Standard
+
+\change_inserted 1986246365 1320786351
\begin_inset Tabular
<lyxtabular version="3" rows="4" columns="2">
<features tabularvalignment="middle">
@@ -1377,6 +4287,8 @@ Immediately following these general headers, there may be device-specific
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
Bits
\end_layout
@@ -1386,6 +4298,8 @@ Bits
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
Device Specific
\end_layout
@@ -1397,6 +4311,8 @@ Device Specific
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
Read/Write
\end_layout
@@ -1406,6 +4322,8 @@ Read/Write
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
Device Specific
\end_layout
@@ -1417,6 +4335,8 @@ Device Specific
\begin_inset Text
\begin_layout Plain Layout
+
+\change_inserted 1986246365 1320786351
Purpose
\end_layout
@@ -1427,6 +4347,8 @@ Purpose
\begin_layout Plain Layout
+\change_inserted 1986246365 1320786351
+
\size footnotesize
Device Specific...
\end_layout
@@ -1440,6 +4362,8 @@ Device Specific...
\begin_layout Plain Layout
+\change_inserted 1986246365 1320786351
+
\end_layout
\end_inset
@@ -1449,6 +4373,8 @@ Device Specific...
\begin_layout Plain Layout
+\change_inserted 1986246365 1320786351
+
\end_layout
\end_inset
@@ -1461,6 +4387,15 @@ Device Specific...
\end_layout
+\begin_layout Standard
+
+\change_inserted 1986246365 1320786619
+Legacy device-specific headers are supported for backwards compatibility.
+ As such, they are not required to map the whole device configuration structure
+ - only the initial segment expected by legacy drivers needs to be mapped.
+ The size of such legacy segment size is device specific.
+\end_layout
+
\begin_layout Subsubsection
Device Status
\end_layout
@@ -1531,8 +4466,10 @@ name "sub:Feature-Bits"
The least significant 31 bits of the first configuration field indicates
the features that the device supports (the high bit is reserved, and will
be used to indicate the presence of future feature bits elsewhere).
- If more than 31 feature bits are supported, the device indicates so by
- setting feature bit 31 (see
+
+\change_deleted 1986246365 1320784929
+If more than 31 feature bits are supported, the device indicates so by setting
+ feature bit 31 (see
\begin_inset CommandInset ref
LatexCommand ref
reference "cha:Reserved-Feature-Bits"
@@ -1540,7 +4477,9 @@ reference "cha:Reserved-Feature-Bits"
\end_inset
).
- The bits are allocated as follows:
+
+\change_unchanged
+The bits are allocated as follows:
\end_layout
\begin_layout Description
@@ -1615,10 +4554,14 @@ This allows for forwards and backwards compatibility: if the device is enhanced
\end_layout
\begin_layout Standard
+
+\change_deleted 1986246365 1320784940
Access to feature bits 32 to 63 is enabled by Guest by setting feature bit
31.
If this bit is unset, Device must assume that all feature bits > 31 are
unset.
+\change_unchanged
+
\end_layout
\begin_layout Subsubsection
@@ -1629,10 +4572,14 @@ Configuration/Queue Vectors
When MSI-X capability is present and enabled in the device (through standard
PCI configuration space) 4 bytes at byte offset 20 are used to map configuratio
n change and queue interrupts to MSI-X vectors.
- In this case, the ISR Status field is unused, and device specific configuration
- starts at byte offset 24 in virtio header structure.
+ In this case, the ISR Status field is unused
+\change_deleted 1986246365 1320784981
+, and device specific configuration starts at byte offset 24 in virtio header
+ structure.
When MSI-X capability is not enabled, device specific configuration starts
- at byte offset 20 in virtio header.
+ at byte offset 20 in virtio header
+\change_unchanged
+.
\end_layout
\begin_layout Standard
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
^ permalink raw reply related
* Re: virtio-pci new configuration proposal
From: Michael S. Tsirkin @ 2011-11-08 21:31 UTC (permalink / raw)
To: Rusty Russell
Cc: Anthony Liguori, virtualization, Sasha Levin, kvm, linux-kernel
In-Reply-To: <87vcqurk25.fsf@rustcorp.com.au>
On Tue, Nov 08, 2011 at 08:51:38PM +1030, Rusty Russell wrote:
> On Tue, 8 Nov 2011 08:32:50 +0200, "Michael S. Tsirkin" <mst@redhat.com> wrote:
> > On Tue, Nov 08, 2011 at 10:23:33AM +1030, Rusty Russell wrote:
> > > Even so, should we just use the PCI cap list, and have each
> > > cap entry just contain a BIR & offset?
> > >
> > > Thanks,
> > > Rusty.
> >
> > And size :)
> > I say, Rusty, did you see my patch? That's what it's doing,
> > I also addressed the issue that with KVM on x86, PIO is faster
> > than MMIO so we need to use it for notifications/isr.
>
> Faster? Really? Why?
I think, because it doesn't need to be emulated to get the address
and the value. There are so many ways on x86 to do memory
access, you need a lot of code to figure out what's going on.
> Were the ppc guys right that's it's obsolescent?
For PCI - surely not. PCI Express spec tries to discourage its usage.
But support is there even in Express.
> Because PIO is going to be ugly AFAICT for every non-x86 platform.
>
> Cheers,
> Rusty.
>
So we should make the BAR MMIO on non-x86 host, PIO on x86.
Guest should just map and use what it's given.
--
MST
^ permalink raw reply
* [PATCH v2 3/3] Use separate struct console structure for each hvc_console.
From: Miche Baker-Harvey @ 2011-11-08 19:30 UTC (permalink / raw)
To: virtualization
In-Reply-To: <20111108192949.30618.3953.stgit@miche.sea.corp.google.com>
It is possible to make any virtio_console port be a console
by sending VIRITO_CONSOLE_CONSOLE_PORT. But hvc_alloc was
using a single struct console hvc_console, which contains
both an index and flags which are per-port.
This adds a separate struct console for each virtio_console
that is CONSOLE_PORT.
Signed-off-by: Miche Baker-Harvey <miche@google.com>
---
drivers/tty/hvc/hvc_console.c | 20 ++++++++++++++++++++
drivers/tty/hvc/hvc_console.h | 1 +
2 files changed, 21 insertions(+), 0 deletions(-)
diff --git a/drivers/tty/hvc/hvc_console.c b/drivers/tty/hvc/hvc_console.c
index 09a6159..24a84d6 100644
--- a/drivers/tty/hvc/hvc_console.c
+++ b/drivers/tty/hvc/hvc_console.c
@@ -247,6 +247,7 @@ static void destroy_hvc_struct(struct kref *kref)
spin_unlock(&hvc_structs_lock);
+ kfree(hp->hvc_console);
kfree(hp);
}
@@ -827,6 +828,7 @@ struct hvc_struct *hvc_alloc(uint32_t vtermno, int data,
int outbuf_size)
{
struct hvc_struct *hp;
+ struct console *cp;
int i;
/* We wait until a driver actually comes along */
@@ -854,6 +856,17 @@ struct hvc_struct *hvc_alloc(uint32_t vtermno, int data,
kref_init(&hp->kref);
INIT_WORK(&hp->tty_resize, hvc_set_winsz);
+ /*
+ * Make each console its own struct console.
+ */
+ cp = kmemdup(&hvc_console, sizeof(*cp), GFP_KERNEL);
+ if (!cp) {
+ kfree(hp);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ hp->hvc_console = cp;
+
spin_lock_init(&hp->lock);
spin_lock(&hvc_structs_lock);
@@ -872,8 +885,13 @@ struct hvc_struct *hvc_alloc(uint32_t vtermno, int data,
hp->index = i;
+ cp->index = i;
+ vtermnos[i] = vtermno;
+ cons_ops[i] = ops;
+
list_add_tail(&(hp->next), &hvc_structs);
spin_unlock(&hvc_structs_lock);
+ register_console(cp);
return hp;
}
@@ -884,6 +902,8 @@ int hvc_remove(struct hvc_struct *hp)
unsigned long flags;
struct tty_struct *tty;
+ BUG_ON(!hp->hvc_console);
+ unregister_console(hp->hvc_console);
spin_lock_irqsave(&hp->lock, flags);
tty = tty_kref_get(hp->tty);
diff --git a/drivers/tty/hvc/hvc_console.h b/drivers/tty/hvc/hvc_console.h
index c335a14..2d20ab7 100644
--- a/drivers/tty/hvc/hvc_console.h
+++ b/drivers/tty/hvc/hvc_console.h
@@ -58,6 +58,7 @@ struct hvc_struct {
const struct hv_ops *ops;
int irq_requested;
int data;
+ struct console *hvc_console;
struct winsize ws;
struct work_struct tty_resize;
struct list_head next;
^ permalink raw reply related
* [PATCH v2 2/3] hvc_init(): Enforce one-time initialization.
From: Miche Baker-Harvey @ 2011-11-08 19:29 UTC (permalink / raw)
To: virtualization
In-Reply-To: <20111108192949.30618.3953.stgit@miche.sea.corp.google.com>
hvc_init() must only be called once, and no thread should continue with hvc_alloc()
until after initialization is complete. The original code does not enforce either
of these requirements. A new mutex limits entry to hvc_init() to a single thread,
and blocks all later comers until it has completed.
This patch fixes multiple crash symptoms.
Signed-off-by: Miche Baker-Harvey <miche@google.com>
---
drivers/tty/hvc/hvc_console.c | 13 +++++++++++--
1 files changed, 11 insertions(+), 2 deletions(-)
diff --git a/drivers/tty/hvc/hvc_console.c b/drivers/tty/hvc/hvc_console.c
index b6b2d18..09a6159 100644
--- a/drivers/tty/hvc/hvc_console.c
+++ b/drivers/tty/hvc/hvc_console.c
@@ -29,8 +29,9 @@
#include <linux/kernel.h>
#include <linux/kthread.h>
#include <linux/list.h>
-#include <linux/module.h>
#include <linux/major.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
#include <linux/sysrq.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
@@ -84,6 +85,10 @@ static LIST_HEAD(hvc_structs);
* list traversal.
*/
static DEFINE_SPINLOCK(hvc_structs_lock);
+/*
+ * only one task does allocation at a time.
+ */
+static DEFINE_MUTEX(hvc_ports_mutex);
/*
* This value is used to assign a tty->index value to a hvc_struct based
@@ -825,11 +830,15 @@ struct hvc_struct *hvc_alloc(uint32_t vtermno, int data,
int i;
/* We wait until a driver actually comes along */
+ mutex_lock(&hvc_ports_mutex);
if (!hvc_driver) {
int err = hvc_init();
- if (err)
+ if (err) {
+ mutex_unlock(&hvc_ports_mutex);
return ERR_PTR(err);
+ }
}
+ mutex_unlock(&hvc_ports_mutex);
hp = kzalloc(ALIGN(sizeof(*hp), sizeof(long)) + outbuf_size,
GFP_KERNEL);
^ permalink raw reply related
* [PATCH v2 1/3] virtio_console: Fix locking of vtermno.
From: Miche Baker-Harvey @ 2011-11-08 19:29 UTC (permalink / raw)
To: virtualization
In-Reply-To: <20111108192949.30618.3953.stgit@miche.sea.corp.google.com>
Some modifications of vtermno were not done under the spinlock.
Moved assignment from vtermno and increment of vtermno together,
putting both under the spinlock. Revert vtermno on failure.
Signed-off-by: Miche Baker-Harvey <miche@google.com>
---
drivers/char/virtio_console.c | 9 ++++++---
1 files changed, 6 insertions(+), 3 deletions(-)
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index 8e3c46d..9722e76 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -987,18 +987,21 @@ int init_port_console(struct port *port)
* pointers. The final argument is the output buffer size: we
* can do any size, so we put PAGE_SIZE here.
*/
- port->cons.vtermno = pdrvdata.next_vtermno;
+ spin_lock_irq(&pdrvdata_lock);
+ port->cons.vtermno = pdrvdata.next_vtermno++;
+ spin_unlock_irq(&pdrvdata_lock);
port->cons.hvc = hvc_alloc(port->cons.vtermno, 0, &hv_ops, PAGE_SIZE);
+ spin_lock_irq(&pdrvdata_lock);
if (IS_ERR(port->cons.hvc)) {
ret = PTR_ERR(port->cons.hvc);
dev_err(port->dev,
"error %d allocating hvc for port\n", ret);
port->cons.hvc = NULL;
+ port->cons.vtermno = pdrvdata.next_vtermno--;
+ spin_unlock_irq(&pdrvdata_lock);
return ret;
}
- spin_lock_irq(&pdrvdata_lock);
- pdrvdata.next_vtermno++;
list_add_tail(&port->cons.list, &pdrvdata.consoles);
spin_unlock_irq(&pdrvdata_lock);
port->guest_connected = true;
^ permalink raw reply related
* [PATCH RFC v2 0/3] Support multiple VirtioConsoles.
From: Miche Baker-Harvey @ 2011-11-08 19:29 UTC (permalink / raw)
To: virtualization
(Amit pointed out that the patches never went out. This is a resend of
the series meant to go out on 11/2/2011; I've marked it "v2".)
This patchset applies to linux-next/next-20111102.
This series implements support for multiple virtio_consoles using KVM.
This patchset addresses several issues associated with trying to
establish multiple virtio consoles.
I'm trying to start a guest via KVM that supports multiple virtual
consoles, with getty's on each, and with some being console devices.
These patches let me establish more than one VirtioConsole (I'm
running eight at the moment), and enable console output appearing on
one of them. It still doesn't successfully generate console output on
multiple VirtioConsoles.
Let me apologise for my last patch having gotten into Linus' tree, and
leaving other people to deal with crashes. I had meant to be asking
for guidance, but I didn't mark it as "RFC".
This series reflects the input from Konrad Rzeszutek, Amit Shah, Stephen
Boyd, and Rusty Russell. I think we do have to limit hvc_alloc() to one
thread.
I would appreciate any comments or feedback, or accept if appropriate.
Thanks,
Miche Baker-Harvey
---
Miche Baker-Harvey (3):
virtio_console: Fix locking of vtermno.
hvc_init(): Enforce one-time initialization.
Use separate struct console structure for each hvc_console.
drivers/char/virtio_console.c | 9 ++++++---
drivers/tty/hvc/hvc_console.c | 33 +++++++++++++++++++++++++++++++--
drivers/tty/hvc/hvc_console.h | 1 +
3 files changed, 38 insertions(+), 5 deletions(-)
--
^ permalink raw reply
* [PATCH 1/1] Staging: hv: storvsc: Move the storage driver out of the staging area
From: K. Y. Srinivasan @ 2011-11-08 18:13 UTC (permalink / raw)
To: gregkh, linux-kernel, devel, virtualization, linux-scsi, ohering,
James.Bottomley
Cc: K. Y. Srinivasan
The storage driver (storvsc_drv.c) handles all block storage devices
assigned to Linux guests hosted on Hyper-V. This driver has been in the
staging tree for a while and this patch moves it out of the staging area.
As per Greg's recommendation, this patch makes no changes to the staging/hv
directory. Once the driver moves out of staging, we will cleanup the
staging/hv directory.
This patch includes all the patches that I have sent against the staging/hv
tree to address the comments I have gotten to date on this storage driver.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
---
drivers/scsi/Kconfig | 8 +
drivers/scsi/Makefile | 3 +
drivers/scsi/storvsc_drv.c | 1567 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 1578 insertions(+), 0 deletions(-)
create mode 100644 drivers/scsi/storvsc_drv.c
diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig
index aa573c3..2f72565 100644
--- a/drivers/scsi/Kconfig
+++ b/drivers/scsi/Kconfig
@@ -676,6 +676,14 @@ config VMWARE_PVSCSI
To compile this driver as a module, choose M here: the
module will be called vmw_pvscsi.
+config HYPERV_STORAGE
+ tristate "Microsoft Hyper-V virtual storage driver"
+ depends on SCSI && HYPERV
+ default HYPERV
+ help
+ Select this option to enable the Hyper-V virtual storage driver.
+
+
config LIBFC
tristate "LibFC module"
select SCSI_FC_ATTRS
diff --git a/drivers/scsi/Makefile b/drivers/scsi/Makefile
index 2b88749..e4c1a69 100644
--- a/drivers/scsi/Makefile
+++ b/drivers/scsi/Makefile
@@ -142,6 +142,7 @@ obj-$(CONFIG_SCSI_BNX2_ISCSI) += libiscsi.o bnx2i/
obj-$(CONFIG_BE2ISCSI) += libiscsi.o be2iscsi/
obj-$(CONFIG_SCSI_PMCRAID) += pmcraid.o
obj-$(CONFIG_VMWARE_PVSCSI) += vmw_pvscsi.o
+obj-$(CONFIG_HYPERV_STORAGE) += hv_storvsc.o
obj-$(CONFIG_ARM) += arm/
@@ -170,6 +171,8 @@ scsi_mod-$(CONFIG_SCSI_PROC_FS) += scsi_proc.o
scsi_mod-y += scsi_trace.o
scsi_mod-$(CONFIG_PM) += scsi_pm.o
+hv_storvsc-y := storvsc_drv.o
+
scsi_tgt-y += scsi_tgt_lib.o scsi_tgt_if.o
sd_mod-objs := sd.o
diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
new file mode 100644
index 0000000..0245143
--- /dev/null
+++ b/drivers/scsi/storvsc_drv.c
@@ -0,0 +1,1567 @@
+/*
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ * Haiyang Zhang <haiyangz@microsoft.com>
+ * Hank Janssen <hjanssen@microsoft.com>
+ * K. Y. Srinivasan <kys@microsoft.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/wait.h>
+#include <linux/sched.h>
+#include <linux/completion.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/hyperv.h>
+#include <linux/mempool.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_tcq.h>
+#include <scsi/scsi_eh.h>
+#include <scsi/scsi_devinfo.h>
+#include <scsi/scsi_dbg.h>
+
+
+#define STORVSC_MIN_BUF_NR 64
+#define STORVSC_RING_BUFFER_SIZE (20*PAGE_SIZE)
+static int storvsc_ringbuffer_size = STORVSC_RING_BUFFER_SIZE;
+
+module_param(storvsc_ringbuffer_size, int, S_IRUGO);
+MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)");
+
+/* to alert the user that structure sizes may be mismatched even though the */
+/* protocol versions match. */
+
+
+#define REVISION_STRING(REVISION_) #REVISION_
+#define FILL_VMSTOR_REVISION(RESULT_LVALUE_) \
+ do { \
+ char *revision_string \
+ = REVISION_STRING($Rev : 6 $) + 6; \
+ RESULT_LVALUE_ = 0; \
+ while (*revision_string >= '0' \
+ && *revision_string <= '9') { \
+ RESULT_LVALUE_ *= 10; \
+ RESULT_LVALUE_ += *revision_string - '0'; \
+ revision_string++; \
+ } \
+ } while (0)
+
+/* Major/minor macros. Minor version is in LSB, meaning that earlier flat */
+/* version numbers will be interpreted as "0.x" (i.e., 1 becomes 0.1). */
+#define VMSTOR_PROTOCOL_MAJOR(VERSION_) (((VERSION_) >> 8) & 0xff)
+#define VMSTOR_PROTOCOL_MINOR(VERSION_) (((VERSION_)) & 0xff)
+#define VMSTOR_PROTOCOL_VERSION(MAJOR_, MINOR_) ((((MAJOR_) & 0xff) << 8) | \
+ (((MINOR_) & 0xff)))
+#define VMSTOR_INVALID_PROTOCOL_VERSION (-1)
+
+/* Version history: */
+/* V1 Beta 0.1 */
+/* V1 RC < 2008/1/31 1.0 */
+/* V1 RC > 2008/1/31 2.0 */
+#define VMSTOR_PROTOCOL_VERSION_CURRENT VMSTOR_PROTOCOL_VERSION(4, 2)
+
+
+
+
+/* This will get replaced with the max transfer length that is possible on */
+/* the host adapter. */
+/* The max transfer length will be published when we offer a vmbus channel. */
+#define MAX_TRANSFER_LENGTH 0x40000
+#define DEFAULT_PACKET_SIZE (sizeof(struct vmdata_gpa_direct) + \
+ sizeof(struct vstor_packet) + \
+ sizesizeof(u64) * (MAX_TRANSFER_LENGTH / PAGE_SIZE)))
+
+
+/* Packet structure describing virtual storage requests. */
+enum vstor_packet_operation {
+ VSTOR_OPERATION_COMPLETE_IO = 1,
+ VSTOR_OPERATION_REMOVE_DEVICE = 2,
+ VSTOR_OPERATION_EXECUTE_SRB = 3,
+ VSTOR_OPERATION_RESET_LUN = 4,
+ VSTOR_OPERATION_RESET_ADAPTER = 5,
+ VSTOR_OPERATION_RESET_BUS = 6,
+ VSTOR_OPERATION_BEGIN_INITIALIZATION = 7,
+ VSTOR_OPERATION_END_INITIALIZATION = 8,
+ VSTOR_OPERATION_QUERY_PROTOCOL_VERSION = 9,
+ VSTOR_OPERATION_QUERY_PROPERTIES = 10,
+ VSTOR_OPERATION_ENUMERATE_BUS = 11,
+ VSTOR_OPERATION_MAXIMUM = 11
+};
+
+/*
+ * Platform neutral description of a scsi request -
+ * this remains the same across the write regardless of 32/64 bit
+ * note: it's patterned off the SCSI_PASS_THROUGH structure
+ */
+#define CDB16GENERIC_LENGTH 0x10
+
+#ifndef SENSE_BUFFER_SIZE
+#define SENSE_BUFFER_SIZE 0x12
+#endif
+
+#define MAX_DATA_BUF_LEN_WITH_PADDING 0x14
+
+struct vmscsi_request {
+ unsigned short length;
+ unsigned char srb_status;
+ unsigned char scsi_status;
+
+ unsigned char port_number;
+ unsigned char path_id;
+ unsigned char target_id;
+ unsigned char lun;
+
+ unsigned char cdb_length;
+ unsigned char sense_info_length;
+ unsigned char data_in;
+ unsigned char reserved;
+
+ unsigned int data_transfer_length;
+
+ union {
+ unsigned char cdb[CDB16GENERIC_LENGTH];
+ unsigned char sense_data[SENSE_BUFFER_SIZE];
+ unsigned char reserved_array[MAX_DATA_BUF_LEN_WITH_PADDING];
+ };
+} __attribute((packed));
+
+
+/*
+ * This structure is sent during the intialization phase to get the different
+ * properties of the channel.
+ */
+struct vmstorage_channel_properties {
+ unsigned short protocol_version;
+ unsigned char path_id;
+ unsigned char target_id;
+
+ /* Note: port number is only really known on the client side */
+ unsigned int port_number;
+ unsigned int flags;
+ unsigned int max_transfer_bytes;
+
+ /* This id is unique for each channel and will correspond with */
+ /* vendor specific data in the inquirydata */
+ unsigned long long unique_id;
+} __packed;
+
+/* This structure is sent during the storage protocol negotiations. */
+struct vmstorage_protocol_version {
+ /* Major (MSW) and minor (LSW) version numbers. */
+ unsigned short major_minor;
+
+ /*
+ * Revision number is auto-incremented whenever this file is changed
+ * (See FILL_VMSTOR_REVISION macro above). Mismatch does not
+ * definitely indicate incompatibility--but it does indicate mismatched
+ * builds.
+ */
+ unsigned short revision;
+} __packed;
+
+/* Channel Property Flags */
+#define STORAGE_CHANNEL_REMOVABLE_FLAG 0x1
+#define STORAGE_CHANNEL_EMULATED_IDE_FLAG 0x2
+
+struct vstor_packet {
+ /* Requested operation type */
+ enum vstor_packet_operation operation;
+
+ /* Flags - see below for values */
+ unsigned int flags;
+
+ /* Status of the request returned from the server side. */
+ unsigned int status;
+
+ /* Data payload area */
+ union {
+ /*
+ * Structure used to forward SCSI commands from the
+ * client to the server.
+ */
+ struct vmscsi_request vm_srb;
+
+ /* Structure used to query channel properties. */
+ struct vmstorage_channel_properties storage_channel_properties;
+
+ /* Used during version negotiations. */
+ struct vmstorage_protocol_version version;
+ };
+} __packed;
+
+/* Packet flags */
+/*
+ * This flag indicates that the server should send back a completion for this
+ * packet.
+ */
+#define REQUEST_COMPLETION_FLAG 0x1
+
+/* This is the set of flags that the vsc can set in any packets it sends */
+#define VSC_LEGAL_FLAGS (REQUEST_COMPLETION_FLAG)
+
+
+/* Defines */
+
+#define STORVSC_MAX_IO_REQUESTS 128
+
+/*
+ * In Hyper-V, each port/path/target maps to 1 scsi host adapter. In
+ * reality, the path/target is not used (ie always set to 0) so our
+ * scsi host adapter essentially has 1 bus with 1 target that contains
+ * up to 256 luns.
+ */
+#define STORVSC_MAX_LUNS_PER_TARGET 64
+#define STORVSC_MAX_TARGETS 1
+#define STORVSC_MAX_CHANNELS 1
+#define STORVSC_MAX_CMD_LEN 16
+
+/* Matches Windows-end */
+enum storvsc_request_type {
+ WRITE_TYPE,
+ READ_TYPE,
+ UNKNOWN_TYPE,
+};
+
+
+struct hv_storvsc_request {
+ struct hv_device *device;
+
+ /* Synchronize the request/response if needed */
+ struct completion wait_event;
+
+ unsigned char *sense_buffer;
+ void *context;
+ void (*on_io_completion)(struct hv_storvsc_request *request);
+ struct hv_multipage_buffer data_buffer;
+
+ struct vstor_packet vstor_packet;
+};
+
+
+/* A storvsc device is a device object that contains a vmbus channel */
+struct storvsc_device {
+ struct hv_device *device;
+
+ bool destroy;
+ bool drain_notify;
+ atomic_t num_outstanding_req;
+ struct Scsi_Host *host;
+
+ wait_queue_head_t waiting_to_drain;
+
+ /*
+ * Each unique Port/Path/Target represents 1 channel ie scsi
+ * controller. In reality, the pathid, targetid is always 0
+ * and the port is set by us
+ */
+ unsigned int port_number;
+ unsigned char path_id;
+ unsigned char target_id;
+
+ /* Used for vsc/vsp channel reset process */
+ struct hv_storvsc_request init_request;
+ struct hv_storvsc_request reset_request;
+};
+
+struct hv_host_device {
+ struct hv_device *dev;
+ struct kmem_cache *request_pool;
+ mempool_t *request_mempool;
+ unsigned int port;
+ unsigned char path;
+ unsigned char target;
+};
+
+struct storvsc_cmd_request {
+ struct list_head entry;
+ struct scsi_cmnd *cmd;
+
+ unsigned int bounce_sgl_count;
+ struct scatterlist *bounce_sgl;
+
+ struct hv_storvsc_request request;
+};
+
+struct storvsc_scan_work {
+ struct work_struct work;
+ struct Scsi_Host *host;
+ uint lun;
+};
+
+static void storvsc_bus_scan(struct work_struct *work)
+{
+ struct storvsc_scan_work *wrk;
+ int id, order_id;
+
+ wrk = container_of(work, struct storvsc_scan_work, work);
+ for (id = 0; id < wrk->host->max_id; ++id) {
+ if (wrk->host->reverse_ordering)
+ order_id = wrk->host->max_id - id - 1;
+ else
+ order_id = id;
+
+ scsi_scan_target(&wrk->host->shost_gendev, 0,
+ order_id, SCAN_WILD_CARD, 1);
+ }
+ kfree(wrk);
+}
+
+static void storvsc_remove_lun(struct work_struct *work)
+{
+ struct storvsc_scan_work *wrk;
+ struct scsi_device *sdev;
+
+ wrk = container_of(work, struct storvsc_scan_work, work);
+ if (!scsi_host_get(wrk->host))
+ goto done;
+
+ sdev = scsi_device_lookup(wrk->host, 0, 0, wrk->lun);
+
+ if (sdev) {
+ scsi_remove_device(sdev);
+ scsi_device_put(sdev);
+ }
+ scsi_host_put(wrk->host);
+
+done:
+ kfree(wrk);
+}
+
+static inline struct storvsc_device *get_out_stor_device(
+ struct hv_device *device)
+{
+ struct storvsc_device *stor_device;
+
+ stor_device = hv_get_drvdata(device);
+
+ if (stor_device && stor_device->destroy)
+ stor_device = NULL;
+
+ return stor_device;
+}
+
+
+static inline void storvsc_wait_to_drain(struct storvsc_device *dev)
+{
+ dev->drain_notify = true;
+ wait_event(dev->waiting_to_drain,
+ atomic_read(&dev->num_outstanding_req) == 0);
+ dev->drain_notify = false;
+}
+
+static inline struct storvsc_device *get_in_stor_device(
+ struct hv_device *device)
+{
+ struct storvsc_device *stor_device;
+
+ stor_device = hv_get_drvdata(device);
+
+ if (!stor_device)
+ goto get_in_err;
+
+ /*
+ * If the device is being destroyed; allow incoming
+ * traffic only to cleanup outstanding requests.
+ */
+
+ if (stor_device->destroy &&
+ (atomic_read(&stor_device->num_outstanding_req) == 0))
+ stor_device = NULL;
+
+get_in_err:
+ return stor_device;
+
+}
+
+static int storvsc_channel_init(struct hv_device *device)
+{
+ struct storvsc_device *stor_device;
+ struct hv_storvsc_request *request;
+ struct vstor_packet *vstor_packet;
+ int ret, t;
+
+ stor_device = get_out_stor_device(device);
+ if (!stor_device)
+ return -ENODEV;
+
+ request = &stor_device->init_request;
+ vstor_packet = &request->vstor_packet;
+
+ /*
+ * Now, initiate the vsc/vsp initialization protocol on the open
+ * channel
+ */
+ memset(request, 0, sizeof(struct hv_storvsc_request));
+ init_completion(&request->wait_event);
+ vstor_packet->operation = VSTOR_OPERATION_BEGIN_INITIALIZATION;
+ vstor_packet->flags = REQUEST_COMPLETION_FLAG;
+
+ ret = vmbus_sendpacket(device->channel, vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)request,
+ VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+ if (ret != 0)
+ goto cleanup;
+
+ t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+ if (t == 0) {
+ ret = -ETIMEDOUT;
+ goto cleanup;
+ }
+
+ if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
+ vstor_packet->status != 0)
+ goto cleanup;
+
+
+ /* reuse the packet for version range supported */
+ memset(vstor_packet, 0, sizeof(struct vstor_packet));
+ vstor_packet->operation = VSTOR_OPERATION_QUERY_PROTOCOL_VERSION;
+ vstor_packet->flags = REQUEST_COMPLETION_FLAG;
+
+ vstor_packet->version.major_minor = VMSTOR_PROTOCOL_VERSION_CURRENT;
+ FILL_VMSTOR_REVISION(vstor_packet->version.revision);
+
+ ret = vmbus_sendpacket(device->channel, vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)request,
+ VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+ if (ret != 0)
+ goto cleanup;
+
+ t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+ if (t == 0) {
+ ret = -ETIMEDOUT;
+ goto cleanup;
+ }
+
+ if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
+ vstor_packet->status != 0)
+ goto cleanup;
+
+
+ memset(vstor_packet, 0, sizeof(struct vstor_packet));
+ vstor_packet->operation = VSTOR_OPERATION_QUERY_PROPERTIES;
+ vstor_packet->flags = REQUEST_COMPLETION_FLAG;
+ vstor_packet->storage_channel_properties.port_number =
+ stor_device->port_number;
+
+ ret = vmbus_sendpacket(device->channel, vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)request,
+ VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+
+ if (ret != 0)
+ goto cleanup;
+
+ t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+ if (t == 0) {
+ ret = -ETIMEDOUT;
+ goto cleanup;
+ }
+
+ if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
+ vstor_packet->status != 0)
+ goto cleanup;
+
+ stor_device->path_id = vstor_packet->storage_channel_properties.path_id;
+ stor_device->target_id
+ = vstor_packet->storage_channel_properties.target_id;
+
+ memset(vstor_packet, 0, sizeof(struct vstor_packet));
+ vstor_packet->operation = VSTOR_OPERATION_END_INITIALIZATION;
+ vstor_packet->flags = REQUEST_COMPLETION_FLAG;
+
+ ret = vmbus_sendpacket(device->channel, vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)request,
+ VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+
+ if (ret != 0)
+ goto cleanup;
+
+ t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+ if (t == 0) {
+ ret = -ETIMEDOUT;
+ goto cleanup;
+ }
+
+ if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
+ vstor_packet->status != 0)
+ goto cleanup;
+
+
+cleanup:
+ return ret;
+}
+
+static void storvsc_on_io_completion(struct hv_device *device,
+ struct vstor_packet *vstor_packet,
+ struct hv_storvsc_request *request)
+{
+ struct storvsc_device *stor_device;
+ struct vstor_packet *stor_pkt;
+
+ stor_device = hv_get_drvdata(device);
+ stor_pkt = &request->vstor_packet;
+
+ /*
+ * The current SCSI handling on the host side does
+ * not correctly handle:
+ * INQUIRY command with page code parameter set to 0x80
+ * MODE_SENSE command with cmd[2] == 0x1c
+ *
+ * Setup srb and scsi status so this won't be fatal.
+ * We do this so we can distinguish truly fatal failues
+ * (srb status == 0x4) and off-line the device in that case.
+ */
+
+ if ((stor_pkt->vm_srb.cdb[0] == INQUIRY) ||
+ (stor_pkt->vm_srb.cdb[0] == MODE_SENSE)) {
+ vstor_packet->vm_srb.scsi_status = 0;
+ vstor_packet->vm_srb.srb_status = 0x1;
+ }
+
+
+ /* Copy over the status...etc */
+ stor_pkt->vm_srb.scsi_status = vstor_packet->vm_srb.scsi_status;
+ stor_pkt->vm_srb.srb_status = vstor_packet->vm_srb.srb_status;
+ stor_pkt->vm_srb.sense_info_length =
+ vstor_packet->vm_srb.sense_info_length;
+
+ if (vstor_packet->vm_srb.scsi_status != 0 ||
+ vstor_packet->vm_srb.srb_status != 1){
+ dev_warn(&device->device,
+ "cmd 0x%x scsi status 0x%x srb status 0x%x\n",
+ stor_pkt->vm_srb.cdb[0],
+ vstor_packet->vm_srb.scsi_status,
+ vstor_packet->vm_srb.srb_status);
+ }
+
+ if ((vstor_packet->vm_srb.scsi_status & 0xFF) == 0x02) {
+ /* CHECK_CONDITION */
+ if (vstor_packet->vm_srb.srb_status & 0x80) {
+ /* autosense data available */
+ dev_warn(&device->device,
+ "stor pkt %p autosense data valid - len %d\n",
+ request,
+ vstor_packet->vm_srb.sense_info_length);
+
+ memcpy(request->sense_buffer,
+ vstor_packet->vm_srb.sense_data,
+ vstor_packet->vm_srb.sense_info_length);
+
+ }
+ }
+
+ stor_pkt->vm_srb.data_transfer_length =
+ vstor_packet->vm_srb.data_transfer_length;
+
+ request->on_io_completion(request);
+
+ if (atomic_dec_and_test(&stor_device->num_outstanding_req) &&
+ stor_device->drain_notify)
+ wake_up(&stor_device->waiting_to_drain);
+
+
+}
+
+static void storvsc_on_receive(struct hv_device *device,
+ struct vstor_packet *vstor_packet,
+ struct hv_storvsc_request *request)
+{
+ struct storvsc_scan_work *work;
+ struct storvsc_device *stor_device;
+
+ switch (vstor_packet->operation) {
+ case VSTOR_OPERATION_COMPLETE_IO:
+ storvsc_on_io_completion(device, vstor_packet, request);
+ break;
+
+ case VSTOR_OPERATION_REMOVE_DEVICE:
+ case VSTOR_OPERATION_ENUMERATE_BUS:
+ stor_device = get_in_stor_device(device);
+ work = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC);
+ if (!work)
+ return;
+
+ INIT_WORK(&work->work, storvsc_bus_scan);
+ work->host = stor_device->host;
+ schedule_work(&work->work);
+ break;
+
+ default:
+ break;
+ }
+}
+
+static void storvsc_on_channel_callback(void *context)
+{
+ struct hv_device *device = (struct hv_device *)context;
+ struct storvsc_device *stor_device;
+ u32 bytes_recvd;
+ u64 request_id;
+ unsigned char packet[ALIGN(sizeof(struct vstor_packet), 8)];
+ struct hv_storvsc_request *request;
+ int ret;
+
+
+ stor_device = get_in_stor_device(device);
+ if (!stor_device)
+ return;
+
+ do {
+ ret = vmbus_recvpacket(device->channel, packet,
+ ALIGN(sizeof(struct vstor_packet), 8),
+ &bytes_recvd, &request_id);
+ if (ret == 0 && bytes_recvd > 0) {
+
+ request = (struct hv_storvsc_request *)
+ (unsigned long)request_id;
+
+ if ((request == &stor_device->init_request) ||
+ (request == &stor_device->reset_request)) {
+
+ memcpy(&request->vstor_packet, packet,
+ sizeof(struct vstor_packet));
+ complete(&request->wait_event);
+ } else {
+ storvsc_on_receive(device,
+ (struct vstor_packet *)packet,
+ request);
+ }
+ } else {
+ break;
+ }
+ } while (1);
+
+ return;
+}
+
+static int storvsc_connect_to_vsp(struct hv_device *device, u32 ring_size)
+{
+ struct vmstorage_channel_properties props;
+ int ret;
+
+ memset(&props, 0, sizeof(struct vmstorage_channel_properties));
+
+ /* Open the channel */
+ ret = vmbus_open(device->channel,
+ ring_size,
+ ring_size,
+ (void *)&props,
+ sizeof(struct vmstorage_channel_properties),
+ storvsc_on_channel_callback, device);
+
+ if (ret != 0)
+ return ret;
+
+ ret = storvsc_channel_init(device);
+
+ return ret;
+}
+
+static int storvsc_dev_remove(struct hv_device *device)
+{
+ struct storvsc_device *stor_device;
+ unsigned long flags;
+
+ stor_device = hv_get_drvdata(device);
+
+ spin_lock_irqsave(&device->channel->inbound_lock, flags);
+ stor_device->destroy = true;
+ spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
+
+ /*
+ * At this point, all outbound traffic should be disable. We
+ * only allow inbound traffic (responses) to proceed so that
+ * outstanding requests can be completed.
+ */
+
+ storvsc_wait_to_drain(stor_device);
+
+ /*
+ * Since we have already drained, we don't need to busy wait
+ * as was done in final_release_stor_device()
+ * Note that we cannot set the ext pointer to NULL until
+ * we have drained - to drain the outgoing packets, we need to
+ * allow incoming packets.
+ */
+ spin_lock_irqsave(&device->channel->inbound_lock, flags);
+ hv_set_drvdata(device, NULL);
+ spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
+
+ /* Close the channel */
+ vmbus_close(device->channel);
+
+ kfree(stor_device);
+ return 0;
+}
+
+static int storvsc_do_io(struct hv_device *device,
+ struct hv_storvsc_request *request)
+{
+ struct storvsc_device *stor_device;
+ struct vstor_packet *vstor_packet;
+ int ret = 0;
+
+ vstor_packet = &request->vstor_packet;
+ stor_device = get_out_stor_device(device);
+
+ if (!stor_device)
+ return -ENODEV;
+
+
+ request->device = device;
+
+
+ vstor_packet->flags |= REQUEST_COMPLETION_FLAG;
+
+ vstor_packet->vm_srb.length = sizeof(struct vmscsi_request);
+
+
+ vstor_packet->vm_srb.sense_info_length = SENSE_BUFFER_SIZE;
+
+
+ vstor_packet->vm_srb.data_transfer_length =
+ request->data_buffer.len;
+
+ vstor_packet->operation = VSTOR_OPERATION_EXECUTE_SRB;
+
+ if (request->data_buffer.len) {
+ ret = vmbus_sendpacket_multipagebuffer(device->channel,
+ &request->data_buffer,
+ vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)request);
+ } else {
+ ret = vmbus_sendpacket(device->channel, vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)request,
+ VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+ }
+
+ if (ret != 0)
+ return ret;
+
+ atomic_inc(&stor_device->num_outstanding_req);
+
+ return ret;
+}
+
+static void storvsc_get_ide_info(struct hv_device *dev, int *target, int *path)
+{
+ *target =
+ dev->dev_instance.b[5] << 8 | dev->dev_instance.b[4];
+
+ *path =
+ dev->dev_instance.b[3] << 24 |
+ dev->dev_instance.b[2] << 16 |
+ dev->dev_instance.b[1] << 8 | dev->dev_instance.b[0];
+}
+
+
+static int storvsc_device_alloc(struct scsi_device *sdevice)
+{
+ /*
+ * This enables luns to be located sparsely. Otherwise, we may not
+ * discovered them.
+ */
+ sdevice->sdev_bflags |= BLIST_SPARSELUN | BLIST_LARGELUN;
+ return 0;
+}
+
+static int storvsc_merge_bvec(struct request_queue *q,
+ struct bvec_merge_data *bmd, struct bio_vec *bvec)
+{
+ /* checking done by caller. */
+ return bvec->bv_len;
+}
+
+static int storvsc_device_configure(struct scsi_device *sdevice)
+{
+ scsi_adjust_queue_depth(sdevice, MSG_SIMPLE_TAG,
+ STORVSC_MAX_IO_REQUESTS);
+
+ blk_queue_max_segment_size(sdevice->request_queue, PAGE_SIZE);
+
+ blk_queue_merge_bvec(sdevice->request_queue, storvsc_merge_bvec);
+
+ blk_queue_bounce_limit(sdevice->request_queue, BLK_BOUNCE_ANY);
+
+ return 0;
+}
+
+static void destroy_bounce_buffer(struct scatterlist *sgl,
+ unsigned int sg_count)
+{
+ int i;
+ struct page *page_buf;
+
+ for (i = 0; i < sg_count; i++) {
+ page_buf = sg_page((&sgl[i]));
+ if (page_buf != NULL)
+ __free_page(page_buf);
+ }
+
+ kfree(sgl);
+}
+
+static int do_bounce_buffer(struct scatterlist *sgl, unsigned int sg_count)
+{
+ int i;
+
+ /* No need to check */
+ if (sg_count < 2)
+ return -1;
+
+ /* We have at least 2 sg entries */
+ for (i = 0; i < sg_count; i++) {
+ if (i == 0) {
+ /* make sure 1st one does not have hole */
+ if (sgl[i].offset + sgl[i].length != PAGE_SIZE)
+ return i;
+ } else if (i == sg_count - 1) {
+ /* make sure last one does not have hole */
+ if (sgl[i].offset != 0)
+ return i;
+ } else {
+ /* make sure no hole in the middle */
+ if (sgl[i].length != PAGE_SIZE || sgl[i].offset != 0)
+ return i;
+ }
+ }
+ return -1;
+}
+
+static struct scatterlist *create_bounce_buffer(struct scatterlist *sgl,
+ unsigned int sg_count,
+ unsigned int len)
+{
+ int i;
+ int num_pages;
+ struct scatterlist *bounce_sgl;
+ struct page *page_buf;
+
+ num_pages = ALIGN(len, PAGE_SIZE) >> PAGE_SHIFT;
+
+ bounce_sgl = kcalloc(num_pages, sizeof(struct scatterlist), GFP_ATOMIC);
+ if (!bounce_sgl)
+ return NULL;
+
+ for (i = 0; i < num_pages; i++) {
+ page_buf = alloc_page(GFP_ATOMIC);
+ if (!page_buf)
+ goto cleanup;
+ sg_set_page(&bounce_sgl[i], page_buf, 0, 0);
+ }
+
+ return bounce_sgl;
+
+cleanup:
+ destroy_bounce_buffer(bounce_sgl, num_pages);
+ return NULL;
+}
+
+
+/* Assume the original sgl has enough room */
+static unsigned int copy_from_bounce_buffer(struct scatterlist *orig_sgl,
+ struct scatterlist *bounce_sgl,
+ unsigned int orig_sgl_count)
+{
+ int i;
+ int j = 0;
+ unsigned long src, dest;
+ unsigned int srclen, destlen, copylen;
+ unsigned int total_copied = 0;
+ unsigned long bounce_addr = 0;
+ unsigned long dest_addr = 0;
+ unsigned long flags;
+
+ local_irq_save(flags);
+
+ for (i = 0; i < orig_sgl_count; i++) {
+ dest_addr = (unsigned long)kmap_atomic(sg_page((&orig_sgl[i])),
+ KM_IRQ0) + orig_sgl[i].offset;
+ dest = dest_addr;
+ destlen = orig_sgl[i].length;
+
+ if (bounce_addr == 0)
+ bounce_addr =
+ (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])),
+ KM_IRQ0);
+
+ while (destlen) {
+ src = bounce_addr + bounce_sgl[j].offset;
+ srclen = bounce_sgl[j].length - bounce_sgl[j].offset;
+
+ copylen = min(srclen, destlen);
+ memcpy((void *)dest, (void *)src, copylen);
+
+ total_copied += copylen;
+ bounce_sgl[j].offset += copylen;
+ destlen -= copylen;
+ dest += copylen;
+
+ if (bounce_sgl[j].offset == bounce_sgl[j].length) {
+ /* full */
+ kunmap_atomic((void *)bounce_addr, KM_IRQ0);
+ j++;
+
+ /* if we need to use another bounce buffer */
+ if (destlen || i != orig_sgl_count - 1)
+ bounce_addr =
+ (unsigned long)kmap_atomic(
+ sg_page((&bounce_sgl[j])), KM_IRQ0);
+ } else if (destlen == 0 && i == orig_sgl_count - 1) {
+ /* unmap the last bounce that is < PAGE_SIZE */
+ kunmap_atomic((void *)bounce_addr, KM_IRQ0);
+ }
+ }
+
+ kunmap_atomic((void *)(dest_addr - orig_sgl[i].offset),
+ KM_IRQ0);
+ }
+
+ local_irq_restore(flags);
+
+ return total_copied;
+}
+
+
+/* Assume the bounce_sgl has enough room ie using the create_bounce_buffer() */
+static unsigned int copy_to_bounce_buffer(struct scatterlist *orig_sgl,
+ struct scatterlist *bounce_sgl,
+ unsigned int orig_sgl_count)
+{
+ int i;
+ int j = 0;
+ unsigned long src, dest;
+ unsigned int srclen, destlen, copylen;
+ unsigned int total_copied = 0;
+ unsigned long bounce_addr = 0;
+ unsigned long src_addr = 0;
+ unsigned long flags;
+
+ local_irq_save(flags);
+
+ for (i = 0; i < orig_sgl_count; i++) {
+ src_addr = (unsigned long)kmap_atomic(sg_page((&orig_sgl[i])),
+ KM_IRQ0) + orig_sgl[i].offset;
+ src = src_addr;
+ srclen = orig_sgl[i].length;
+
+ if (bounce_addr == 0)
+ bounce_addr =
+ (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])),
+ KM_IRQ0);
+
+ while (srclen) {
+ /* assume bounce offset always == 0 */
+ dest = bounce_addr + bounce_sgl[j].length;
+ destlen = PAGE_SIZE - bounce_sgl[j].length;
+
+ copylen = min(srclen, destlen);
+ memcpy((void *)dest, (void *)src, copylen);
+
+ total_copied += copylen;
+ bounce_sgl[j].length += copylen;
+ srclen -= copylen;
+ src += copylen;
+
+ if (bounce_sgl[j].length == PAGE_SIZE) {
+ /* full..move to next entry */
+ kunmap_atomic((void *)bounce_addr, KM_IRQ0);
+ j++;
+
+ /* if we need to use another bounce buffer */
+ if (srclen || i != orig_sgl_count - 1)
+ bounce_addr =
+ (unsigned long)kmap_atomic(
+ sg_page((&bounce_sgl[j])), KM_IRQ0);
+
+ } else if (srclen == 0 && i == orig_sgl_count - 1) {
+ /* unmap the last bounce that is < PAGE_SIZE */
+ kunmap_atomic((void *)bounce_addr, KM_IRQ0);
+ }
+ }
+
+ kunmap_atomic((void *)(src_addr - orig_sgl[i].offset), KM_IRQ0);
+ }
+
+ local_irq_restore(flags);
+
+ return total_copied;
+}
+
+
+static int storvsc_remove(struct hv_device *dev)
+{
+ struct storvsc_device *stor_device = hv_get_drvdata(dev);
+ struct Scsi_Host *host = stor_device->host;
+ struct hv_host_device *host_dev = shost_priv(host);
+
+ scsi_remove_host(host);
+
+ scsi_host_put(host);
+
+ storvsc_dev_remove(dev);
+ if (host_dev->request_pool) {
+ mempool_destroy(host_dev->request_mempool);
+ kmem_cache_destroy(host_dev->request_pool);
+ host_dev->request_pool = NULL;
+ host_dev->request_mempool = NULL;
+ }
+ return 0;
+}
+
+
+static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev,
+ sector_t capacity, int *info)
+{
+ sector_t nsect = capacity;
+ sector_t cylinders = nsect;
+ int heads, sectors_pt;
+
+ /*
+ * We are making up these values; let us keep it simple.
+ */
+ heads = 0xff;
+ sectors_pt = 0x3f; /* Sectors per track */
+ sector_div(cylinders, heads * sectors_pt);
+ if ((sector_t)(cylinders + 1) * heads * sectors_pt < nsect)
+ cylinders = 0xffff;
+
+ info[0] = heads;
+ info[1] = sectors_pt;
+ info[2] = (int)cylinders;
+
+ return 0;
+}
+
+static int storvsc_host_reset(struct hv_device *device)
+{
+ struct storvsc_device *stor_device;
+ struct hv_storvsc_request *request;
+ struct vstor_packet *vstor_packet;
+ int ret, t;
+
+
+ stor_device = get_out_stor_device(device);
+ if (!stor_device)
+ return FAILED;
+
+ request = &stor_device->reset_request;
+ vstor_packet = &request->vstor_packet;
+
+ init_completion(&request->wait_event);
+
+ vstor_packet->operation = VSTOR_OPERATION_RESET_BUS;
+ vstor_packet->flags = REQUEST_COMPLETION_FLAG;
+ vstor_packet->vm_srb.path_id = stor_device->path_id;
+
+ ret = vmbus_sendpacket(device->channel, vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)&stor_device->reset_request,
+ VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+ if (ret != 0)
+ return FAILED;
+
+ t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+ if (t == 0)
+ return TIMEOUT_ERROR;
+
+
+ /*
+ * At this point, all outstanding requests in the adapter
+ * should have been flushed out and return to us
+ */
+
+ return SUCCESS;
+}
+
+
+/*
+ * storvsc_host_reset_handler - Reset the scsi HBA
+ */
+static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd)
+{
+ struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
+ struct hv_device *dev = host_dev->dev;
+
+ return storvsc_host_reset(dev);
+}
+
+
+/*
+ * storvsc_command_completion - Command completion processing
+ */
+static void storvsc_command_completion(struct hv_storvsc_request *request)
+{
+ struct storvsc_cmd_request *cmd_request =
+ (struct storvsc_cmd_request *)request->context;
+ struct scsi_cmnd *scmnd = cmd_request->cmd;
+ struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
+ void (*scsi_done_fn)(struct scsi_cmnd *);
+ struct scsi_sense_hdr sense_hdr;
+ struct vmscsi_request *vm_srb;
+ struct storvsc_scan_work *wrk;
+
+ vm_srb = &request->vstor_packet.vm_srb;
+ if (cmd_request->bounce_sgl_count) {
+ if (vm_srb->data_in == READ_TYPE) {
+ copy_from_bounce_buffer(scsi_sglist(scmnd),
+ cmd_request->bounce_sgl,
+ scsi_sg_count(scmnd));
+ destroy_bounce_buffer(cmd_request->bounce_sgl,
+ cmd_request->bounce_sgl_count);
+ }
+ }
+
+ /*
+ * If there is an error; offline the device since all
+ * error recovery strategies would have already been
+ * deployed on the host side.
+ */
+ if (vm_srb->srb_status == 0x4)
+ scmnd->result = DID_TARGET_FAILURE << 16;
+ else
+ scmnd->result = vm_srb->scsi_status;
+
+ /*
+ * If the LUN is invalid; remove the device.
+ */
+ if (vm_srb->srb_status == 0x20) {
+ struct storvsc_device *stor_dev;
+ struct hv_device *dev = host_dev->dev;
+ struct Scsi_Host *host;
+
+ stor_dev = get_in_stor_device(dev);
+ host = stor_dev->host;
+
+ wrk = kmalloc(sizeof(struct storvsc_scan_work),
+ GFP_ATOMIC);
+ if (!wrk) {
+ scmnd->result = DID_TARGET_FAILURE << 16;
+ } else {
+ wrk->host = host;
+ wrk->lun = vm_srb->lun;
+ INIT_WORK(&wrk->work, storvsc_remove_lun);
+ schedule_work(&wrk->work);
+ }
+ }
+
+ if (scmnd->result) {
+ if (scsi_normalize_sense(scmnd->sense_buffer,
+ SCSI_SENSE_BUFFERSIZE, &sense_hdr))
+ scsi_print_sense_hdr("storvsc", &sense_hdr);
+ }
+
+ scsi_set_resid(scmnd,
+ request->data_buffer.len -
+ vm_srb->data_transfer_length);
+
+ scsi_done_fn = scmnd->scsi_done;
+
+ scmnd->host_scribble = NULL;
+ scmnd->scsi_done = NULL;
+
+ scsi_done_fn(scmnd);
+
+ mempool_free(cmd_request, host_dev->request_mempool);
+}
+
+static bool storvsc_check_scsi_cmd(struct scsi_cmnd *scmnd)
+{
+ bool allowed = true;
+ u8 scsi_op = scmnd->cmnd[0];
+
+ switch (scsi_op) {
+ /* smartd sends this command, which will offline the device */
+ case SET_WINDOW:
+ scmnd->result = ILLEGAL_REQUEST << 16;
+ allowed = false;
+ break;
+ default:
+ break;
+ }
+ return allowed;
+}
+
+/*
+ * storvsc_queuecommand - Initiate command processing
+ */
+static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
+{
+ int ret;
+ struct hv_host_device *host_dev = shost_priv(host);
+ struct hv_device *dev = host_dev->dev;
+ struct hv_storvsc_request *request;
+ struct storvsc_cmd_request *cmd_request;
+ unsigned int request_size = 0;
+ int i;
+ struct scatterlist *sgl;
+ unsigned int sg_count = 0;
+ struct vmscsi_request *vm_srb;
+
+ if (storvsc_check_scsi_cmd(scmnd) == false) {
+ scmnd->scsi_done(scmnd);
+ return 0;
+ }
+
+ /* If retrying, no need to prep the cmd */
+ if (scmnd->host_scribble) {
+
+ cmd_request =
+ (struct storvsc_cmd_request *)scmnd->host_scribble;
+
+ goto retry_request;
+ }
+
+ request_size = sizeof(struct storvsc_cmd_request);
+
+ cmd_request = mempool_alloc(host_dev->request_mempool,
+ GFP_ATOMIC);
+ if (!cmd_request)
+ return SCSI_MLQUEUE_DEVICE_BUSY;
+
+ memset(cmd_request, 0, sizeof(struct storvsc_cmd_request));
+
+ /* Setup the cmd request */
+ cmd_request->bounce_sgl_count = 0;
+ cmd_request->bounce_sgl = NULL;
+ cmd_request->cmd = scmnd;
+
+ scmnd->host_scribble = (unsigned char *)cmd_request;
+
+ request = &cmd_request->request;
+ vm_srb = &request->vstor_packet.vm_srb;
+
+
+ /* Build the SRB */
+ switch (scmnd->sc_data_direction) {
+ case DMA_TO_DEVICE:
+ vm_srb->data_in = WRITE_TYPE;
+ break;
+ case DMA_FROM_DEVICE:
+ vm_srb->data_in = READ_TYPE;
+ break;
+ default:
+ vm_srb->data_in = UNKNOWN_TYPE;
+ break;
+ }
+
+ request->on_io_completion = storvsc_command_completion;
+ request->context = cmd_request;/* scmnd; */
+
+ vm_srb->port_number = host_dev->port;
+ vm_srb->path_id = scmnd->device->channel;
+ vm_srb->target_id = scmnd->device->id;
+ vm_srb->lun = scmnd->device->lun;
+
+ vm_srb->cdb_length = scmnd->cmd_len;
+
+ memcpy(vm_srb->cdb, scmnd->cmnd, vm_srb->cdb_length);
+
+ request->sense_buffer = scmnd->sense_buffer;
+
+
+ request->data_buffer.len = scsi_bufflen(scmnd);
+ if (scsi_sg_count(scmnd)) {
+ sgl = (struct scatterlist *)scsi_sglist(scmnd);
+ sg_count = scsi_sg_count(scmnd);
+
+ /* check if we need to bounce the sgl */
+ if (do_bounce_buffer(sgl, scsi_sg_count(scmnd)) != -1) {
+ cmd_request->bounce_sgl =
+ create_bounce_buffer(sgl, scsi_sg_count(scmnd),
+ scsi_bufflen(scmnd));
+ if (!cmd_request->bounce_sgl) {
+ scmnd->host_scribble = NULL;
+ mempool_free(cmd_request,
+ host_dev->request_mempool);
+
+ return SCSI_MLQUEUE_HOST_BUSY;
+ }
+
+ cmd_request->bounce_sgl_count =
+ ALIGN(scsi_bufflen(scmnd), PAGE_SIZE) >>
+ PAGE_SHIFT;
+
+ if (vm_srb->data_in == WRITE_TYPE)
+ copy_to_bounce_buffer(sgl,
+ cmd_request->bounce_sgl,
+ scsi_sg_count(scmnd));
+
+ sgl = cmd_request->bounce_sgl;
+ sg_count = cmd_request->bounce_sgl_count;
+ }
+
+ request->data_buffer.offset = sgl[0].offset;
+
+ for (i = 0; i < sg_count; i++)
+ request->data_buffer.pfn_array[i] =
+ page_to_pfn(sg_page((&sgl[i])));
+
+ } else if (scsi_sglist(scmnd)) {
+ request->data_buffer.offset =
+ virt_to_phys(scsi_sglist(scmnd)) & (PAGE_SIZE-1);
+ request->data_buffer.pfn_array[0] =
+ virt_to_phys(scsi_sglist(scmnd)) >> PAGE_SHIFT;
+ }
+
+retry_request:
+ /* Invokes the vsc to start an IO */
+ ret = storvsc_do_io(dev, &cmd_request->request);
+
+ if (ret == -EAGAIN) {
+ /* no more space */
+
+ if (cmd_request->bounce_sgl_count)
+ destroy_bounce_buffer(cmd_request->bounce_sgl,
+ cmd_request->bounce_sgl_count);
+
+ mempool_free(cmd_request, host_dev->request_mempool);
+
+ scmnd->host_scribble = NULL;
+
+ ret = SCSI_MLQUEUE_DEVICE_BUSY;
+ }
+
+ return ret;
+}
+
+/* Scsi driver */
+static struct scsi_host_template scsi_driver = {
+ .module = THIS_MODULE,
+ .name = "storvsc_host_t",
+ .bios_param = storvsc_get_chs,
+ .queuecommand = storvsc_queuecommand,
+ .eh_host_reset_handler = storvsc_host_reset_handler,
+ .slave_alloc = storvsc_device_alloc,
+ .slave_configure = storvsc_device_configure,
+ .cmd_per_lun = 1,
+ /* 64 max_queue * 1 target */
+ .can_queue = STORVSC_MAX_IO_REQUESTS*STORVSC_MAX_TARGETS,
+ .this_id = -1,
+ /* no use setting to 0 since ll_blk_rw reset it to 1 */
+ /* currently 32 */
+ .sg_tablesize = MAX_MULTIPAGE_BUFFER_COUNT,
+ /*
+ * ENABLE_CLUSTERING allows mutiple physically contig bio_vecs to merge
+ * into 1 sg element. If set, we must limit the max_segment_size to
+ * PAGE_SIZE, otherwise we may get 1 sg element that represents
+ * multiple
+ */
+ /* physically contig pfns (ie sg[x].length > PAGE_SIZE). */
+ .use_clustering = ENABLE_CLUSTERING,
+ /* Make sure we dont get a sg segment crosses a page boundary */
+ .dma_boundary = PAGE_SIZE-1,
+};
+
+enum {
+ SCSI_GUID,
+ IDE_GUID,
+};
+
+static const struct hv_vmbus_device_id id_table[] = {
+ /* SCSI guid */
+ { VMBUS_DEVICE(0xd9, 0x63, 0x61, 0xba, 0xa1, 0x04, 0x29, 0x4d,
+ 0xb6, 0x05, 0x72, 0xe2, 0xff, 0xb1, 0xdc, 0x7f)
+ .driver_data = SCSI_GUID },
+ /* IDE guid */
+ { VMBUS_DEVICE(0x32, 0x26, 0x41, 0x32, 0xcb, 0x86, 0xa2, 0x44,
+ 0x9b, 0x5c, 0x50, 0xd1, 0x41, 0x73, 0x54, 0xf5)
+ .driver_data = IDE_GUID },
+ { },
+};
+
+MODULE_DEVICE_TABLE(vmbus, id_table);
+
+
+/*
+ * storvsc_probe - Add a new device for this driver
+ */
+
+static int storvsc_probe(struct hv_device *device,
+ const struct hv_vmbus_device_id *dev_id)
+{
+ int ret;
+ int number = STORVSC_MIN_BUF_NR;
+ struct Scsi_Host *host;
+ struct hv_host_device *host_dev;
+ bool dev_is_ide = ((dev_id->driver_data == IDE_GUID) ? true : false);
+ int path = 0;
+ int target = 0;
+ struct storvsc_device *stor_device;
+
+ host = scsi_host_alloc(&scsi_driver,
+ sizeof(struct hv_host_device));
+ if (!host)
+ return -ENOMEM;
+
+ host_dev = shost_priv(host);
+ memset(host_dev, 0, sizeof(struct hv_host_device));
+
+ host_dev->port = host->host_no;
+ host_dev->dev = device;
+
+ host_dev->request_pool =
+ kmem_cache_create(dev_name(&device->device),
+ sizeof(struct storvsc_cmd_request), 0,
+ SLAB_HWCACHE_ALIGN, NULL);
+
+ if (!host_dev->request_pool) {
+ scsi_host_put(host);
+ return -ENOMEM;
+ }
+
+ host_dev->request_mempool = mempool_create(number, mempool_alloc_slab,
+ mempool_free_slab,
+ host_dev->request_pool);
+
+ if (!host_dev->request_mempool) {
+ ret = -ENOMEM;
+ goto err_out0;
+ }
+
+ stor_device = kzalloc(sizeof(struct storvsc_device), GFP_KERNEL);
+ if (!stor_device) {
+ ret = -ENOMEM;
+ goto err_out1;
+ }
+
+ stor_device->destroy = false;
+ init_waitqueue_head(&stor_device->waiting_to_drain);
+ stor_device->device = device;
+ stor_device->host = host;
+ hv_set_drvdata(device, stor_device);
+
+ stor_device->port_number = host->host_no;
+ ret = storvsc_connect_to_vsp(device, storvsc_ringbuffer_size);
+ if (ret)
+ goto err_out2;
+
+ if (dev_is_ide)
+ storvsc_get_ide_info(device, &target, &path);
+
+ host_dev->path = stor_device->path_id;
+ host_dev->target = stor_device->target_id;
+
+ /* max # of devices per target */
+ host->max_lun = STORVSC_MAX_LUNS_PER_TARGET;
+ /* max # of targets per channel */
+ host->max_id = STORVSC_MAX_TARGETS;
+ /* max # of channels */
+ host->max_channel = STORVSC_MAX_CHANNELS - 1;
+ /* max cmd length */
+ host->max_cmd_len = STORVSC_MAX_CMD_LEN;
+
+ /* Register the HBA and start the scsi bus scan */
+ ret = scsi_add_host(host, &device->device);
+ if (ret != 0)
+ goto err_out3;
+
+ if (!dev_is_ide) {
+ scsi_scan_host(host);
+ return 0;
+ }
+ ret = scsi_add_device(host, 0, target, 0);
+ if (ret) {
+ scsi_remove_host(host);
+ goto err_out3;
+ }
+ return 0;
+
+err_out3:
+ /*
+ * Once we have connected with the host, we would need to
+ * to invoke storvsc_dev_remove() to rollback this state and
+ * this call also frees up the stor_device; hence the jump around
+ * err_out2 label.
+ */
+ storvsc_dev_remove(device);
+ goto err_out1;
+
+err_out2:
+ kfree(stor_device);
+
+err_out1:
+ mempool_destroy(host_dev->request_mempool);
+
+err_out0:
+ kmem_cache_destroy(host_dev->request_pool);
+ scsi_host_put(host);
+ return ret;
+}
+
+/* The one and only one */
+
+static struct hv_driver storvsc_drv = {
+ .name = KBUILD_MODNAME,
+ .id_table = id_table,
+ .probe = storvsc_probe,
+ .remove = storvsc_remove,
+};
+
+static int __init storvsc_drv_init(void)
+{
+ u32 max_outstanding_req_per_channel;
+
+ /*
+ * Divide the ring buffer data size (which is 1 page less
+ * than the ring buffer size since that page is reserved for
+ * the ring buffer indices) by the max request size (which is
+ * vmbus_channel_packet_multipage_buffer + struct vstor_packet + u64)
+ */
+ max_outstanding_req_per_channel =
+ ((storvsc_ringbuffer_size - PAGE_SIZE) /
+ ALIGN(MAX_MULTIPAGE_BUFFER_PACKET +
+ sizeof(struct vstor_packet) + sizeof(u64),
+ sizeof(u64)));
+
+ if (max_outstanding_req_per_channel <
+ STORVSC_MAX_IO_REQUESTS)
+ return -EINVAL;
+
+ return vmbus_driver_register(&storvsc_drv);
+}
+
+static void __exit storvsc_drv_exit(void)
+{
+ vmbus_driver_unregister(&storvsc_drv);
+}
+
+MODULE_LICENSE("GPL");
+MODULE_VERSION(HV_DRV_VERSION);
+MODULE_DESCRIPTION("Microsoft Hyper-V virtual storage driver");
+module_init(storvsc_drv_init);
+module_exit(storvsc_drv_exit);
--
1.7.4.1
^ permalink raw reply related
* [PATCH 11/11] Staging: hv: storvsc: Support hot-removing of scsi devices
From: K. Y. Srinivasan @ 2011-11-08 17:01 UTC (permalink / raw)
To: gregkh, linux-kernel, devel, virtualization, ohering,
James.Bottomley, hch
Cc: Haiyang Zhang
In-Reply-To: <1320771710-29139-1-git-send-email-kys@microsoft.com>
Support hot-removing of scsi devices.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
---
drivers/staging/hv/storvsc_drv.c | 45 ++++++++++++++++++++++++++++++++++++++
1 files changed, 45 insertions(+), 0 deletions(-)
diff --git a/drivers/staging/hv/storvsc_drv.c b/drivers/staging/hv/storvsc_drv.c
index 7c82d14..0245143 100644
--- a/drivers/staging/hv/storvsc_drv.c
+++ b/drivers/staging/hv/storvsc_drv.c
@@ -328,6 +328,27 @@ static void storvsc_bus_scan(struct work_struct *work)
kfree(wrk);
}
+static void storvsc_remove_lun(struct work_struct *work)
+{
+ struct storvsc_scan_work *wrk;
+ struct scsi_device *sdev;
+
+ wrk = container_of(work, struct storvsc_scan_work, work);
+ if (!scsi_host_get(wrk->host))
+ goto done;
+
+ sdev = scsi_device_lookup(wrk->host, 0, 0, wrk->lun);
+
+ if (sdev) {
+ scsi_remove_device(sdev);
+ scsi_device_put(sdev);
+ }
+ scsi_host_put(wrk->host);
+
+done:
+ kfree(wrk);
+}
+
static inline struct storvsc_device *get_out_stor_device(
struct hv_device *device)
{
@@ -1112,6 +1133,7 @@ static void storvsc_command_completion(struct hv_storvsc_request *request)
void (*scsi_done_fn)(struct scsi_cmnd *);
struct scsi_sense_hdr sense_hdr;
struct vmscsi_request *vm_srb;
+ struct storvsc_scan_work *wrk;
vm_srb = &request->vstor_packet.vm_srb;
if (cmd_request->bounce_sgl_count) {
@@ -1134,6 +1156,29 @@ static void storvsc_command_completion(struct hv_storvsc_request *request)
else
scmnd->result = vm_srb->scsi_status;
+ /*
+ * If the LUN is invalid; remove the device.
+ */
+ if (vm_srb->srb_status == 0x20) {
+ struct storvsc_device *stor_dev;
+ struct hv_device *dev = host_dev->dev;
+ struct Scsi_Host *host;
+
+ stor_dev = get_in_stor_device(dev);
+ host = stor_dev->host;
+
+ wrk = kmalloc(sizeof(struct storvsc_scan_work),
+ GFP_ATOMIC);
+ if (!wrk) {
+ scmnd->result = DID_TARGET_FAILURE << 16;
+ } else {
+ wrk->host = host;
+ wrk->lun = vm_srb->lun;
+ INIT_WORK(&wrk->work, storvsc_remove_lun);
+ schedule_work(&wrk->work);
+ }
+ }
+
if (scmnd->result) {
if (scsi_normalize_sense(scmnd->sense_buffer,
SCSI_SENSE_BUFFERSIZE, &sense_hdr))
--
1.7.4.1
^ permalink raw reply related
* [PATCH 10/11] Staging: hv: storvsc: Support hot add of scsi disks
From: K. Y. Srinivasan @ 2011-11-08 17:01 UTC (permalink / raw)
To: gregkh, linux-kernel, devel, virtualization, ohering,
James.Bottomley, hch
Cc: K. Y. Srinivasan, Haiyang Zhang
In-Reply-To: <1320771710-29139-1-git-send-email-kys@microsoft.com>
Support hot add of scsi disks.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
---
drivers/staging/hv/storvsc_drv.c | 38 ++++++++++++++++++++++++++++++++++++++
1 files changed, 38 insertions(+), 0 deletions(-)
diff --git a/drivers/staging/hv/storvsc_drv.c b/drivers/staging/hv/storvsc_drv.c
index 9153641..7c82d14 100644
--- a/drivers/staging/hv/storvsc_drv.c
+++ b/drivers/staging/hv/storvsc_drv.c
@@ -304,6 +304,30 @@ struct storvsc_cmd_request {
struct hv_storvsc_request request;
};
+struct storvsc_scan_work {
+ struct work_struct work;
+ struct Scsi_Host *host;
+ uint lun;
+};
+
+static void storvsc_bus_scan(struct work_struct *work)
+{
+ struct storvsc_scan_work *wrk;
+ int id, order_id;
+
+ wrk = container_of(work, struct storvsc_scan_work, work);
+ for (id = 0; id < wrk->host->max_id; ++id) {
+ if (wrk->host->reverse_ordering)
+ order_id = wrk->host->max_id - id - 1;
+ else
+ order_id = id;
+
+ scsi_scan_target(&wrk->host->shost_gendev, 0,
+ order_id, SCAN_WILD_CARD, 1);
+ }
+ kfree(wrk);
+}
+
static inline struct storvsc_device *get_out_stor_device(
struct hv_device *device)
{
@@ -551,11 +575,25 @@ static void storvsc_on_receive(struct hv_device *device,
struct vstor_packet *vstor_packet,
struct hv_storvsc_request *request)
{
+ struct storvsc_scan_work *work;
+ struct storvsc_device *stor_device;
+
switch (vstor_packet->operation) {
case VSTOR_OPERATION_COMPLETE_IO:
storvsc_on_io_completion(device, vstor_packet, request);
break;
+
case VSTOR_OPERATION_REMOVE_DEVICE:
+ case VSTOR_OPERATION_ENUMERATE_BUS:
+ stor_device = get_in_stor_device(device);
+ work = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC);
+ if (!work)
+ return;
+
+ INIT_WORK(&work->work, storvsc_bus_scan);
+ work->host = stor_device->host;
+ schedule_work(&work->work);
+ break;
default:
break;
--
1.7.4.1
^ permalink raw reply related
* [PATCH 09/11] Staging: hv: storvsc: Upgrade the vmstor protocol version
From: K. Y. Srinivasan @ 2011-11-08 17:01 UTC (permalink / raw)
To: gregkh, linux-kernel, devel, virtualization, ohering,
James.Bottomley, hch
Cc: Haiyang Zhang
In-Reply-To: <1320771710-29139-1-git-send-email-kys@microsoft.com>
In preparation for supporting hot add/remove of scsi devices,
upgrade the vmstor protocol version.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
---
drivers/staging/hv/storvsc_drv.c | 5 +++--
1 files changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/staging/hv/storvsc_drv.c b/drivers/staging/hv/storvsc_drv.c
index 4cdb417..9153641 100644
--- a/drivers/staging/hv/storvsc_drv.c
+++ b/drivers/staging/hv/storvsc_drv.c
@@ -80,7 +80,7 @@ MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)");
/* V1 Beta 0.1 */
/* V1 RC < 2008/1/31 1.0 */
/* V1 RC > 2008/1/31 2.0 */
-#define VMSTOR_PROTOCOL_VERSION_CURRENT VMSTOR_PROTOCOL_VERSION(2, 0)
+#define VMSTOR_PROTOCOL_VERSION_CURRENT VMSTOR_PROTOCOL_VERSION(4, 2)
@@ -106,7 +106,8 @@ enum vstor_packet_operation {
VSTOR_OPERATION_END_INITIALIZATION = 8,
VSTOR_OPERATION_QUERY_PROTOCOL_VERSION = 9,
VSTOR_OPERATION_QUERY_PROPERTIES = 10,
- VSTOR_OPERATION_MAXIMUM = 10
+ VSTOR_OPERATION_ENUMERATE_BUS = 11,
+ VSTOR_OPERATION_MAXIMUM = 11
};
/*
--
1.7.4.1
^ permalink raw reply related
* [PATCH 08/11] Staging: hv: storvsc: Get rid of an unnecessary forward declaration
From: K. Y. Srinivasan @ 2011-11-08 17:01 UTC (permalink / raw)
To: gregkh, linux-kernel, devel, virtualization, ohering,
James.Bottomley, hch
Cc: K. Y. Srinivasan, Haiyang Zhang
In-Reply-To: <1320771710-29139-1-git-send-email-kys@microsoft.com>
Get rid of an unnecessary forward declaration.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
---
drivers/staging/hv/storvsc_drv.c | 2 --
1 files changed, 0 insertions(+), 2 deletions(-)
diff --git a/drivers/staging/hv/storvsc_drv.c b/drivers/staging/hv/storvsc_drv.c
index 916f5d0..4cdb417 100644
--- a/drivers/staging/hv/storvsc_drv.c
+++ b/drivers/staging/hv/storvsc_drv.c
@@ -236,8 +236,6 @@ struct vstor_packet {
#define STORVSC_MAX_CHANNELS 1
#define STORVSC_MAX_CMD_LEN 16
-struct hv_storvsc_request;
-
/* Matches Windows-end */
enum storvsc_request_type {
WRITE_TYPE,
--
1.7.4.1
^ permalink raw reply related
* [PATCH 07/11] Staging: hv: storvsc: use the macro KBUILD_MODNAME
From: K. Y. Srinivasan @ 2011-11-08 17:01 UTC (permalink / raw)
To: gregkh, linux-kernel, devel, virtualization, ohering,
James.Bottomley, hch
Cc: K. Y. Srinivasan, Haiyang Zhang
In-Reply-To: <1320771710-29139-1-git-send-email-kys@microsoft.com>
Use the macro KBUILD_MODNAME.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
---
drivers/staging/hv/storvsc_drv.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/drivers/staging/hv/storvsc_drv.c b/drivers/staging/hv/storvsc_drv.c
index 827bc68..916f5d0 100644
--- a/drivers/staging/hv/storvsc_drv.c
+++ b/drivers/staging/hv/storvsc_drv.c
@@ -1444,7 +1444,7 @@ err_out0:
/* The one and only one */
static struct hv_driver storvsc_drv = {
- .name = "storvsc",
+ .name = KBUILD_MODNAME,
.id_table = id_table,
.probe = storvsc_probe,
.remove = storvsc_remove,
--
1.7.4.1
^ permalink raw reply related
* [PATCH 06/11] Staging: hv: storvsc: Use the unlocked version queuecommand
From: K. Y. Srinivasan @ 2011-11-08 17:01 UTC (permalink / raw)
To: gregkh, linux-kernel, devel, virtualization, ohering,
James.Bottomley, hch
Cc: K. Y. Srinivasan, Haiyang Zhang
In-Reply-To: <1320771710-29139-1-git-send-email-kys@microsoft.com>
Use the unlocked version queuecommand.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
---
drivers/staging/hv/storvsc_drv.c | 19 +++++--------------
1 files changed, 5 insertions(+), 14 deletions(-)
diff --git a/drivers/staging/hv/storvsc_drv.c b/drivers/staging/hv/storvsc_drv.c
index b21e85f..827bc68 100644
--- a/drivers/staging/hv/storvsc_drv.c
+++ b/drivers/staging/hv/storvsc_drv.c
@@ -1137,11 +1137,10 @@ static bool storvsc_check_scsi_cmd(struct scsi_cmnd *scmnd)
/*
* storvsc_queuecommand - Initiate command processing
*/
-static int storvsc_queuecommand_lck(struct scsi_cmnd *scmnd,
- void (*done)(struct scsi_cmnd *))
+static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
{
int ret;
- struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
+ struct hv_host_device *host_dev = shost_priv(host);
struct hv_device *dev = host_dev->dev;
struct hv_storvsc_request *request;
struct storvsc_cmd_request *cmd_request;
@@ -1152,7 +1151,7 @@ static int storvsc_queuecommand_lck(struct scsi_cmnd *scmnd,
struct vmscsi_request *vm_srb;
if (storvsc_check_scsi_cmd(scmnd) == false) {
- done(scmnd);
+ scmnd->scsi_done(scmnd);
return 0;
}
@@ -1165,16 +1164,13 @@ static int storvsc_queuecommand_lck(struct scsi_cmnd *scmnd,
goto retry_request;
}
- scmnd->scsi_done = done;
-
request_size = sizeof(struct storvsc_cmd_request);
cmd_request = mempool_alloc(host_dev->request_mempool,
GFP_ATOMIC);
- if (!cmd_request) {
- scmnd->scsi_done = NULL;
+ if (!cmd_request)
return SCSI_MLQUEUE_DEVICE_BUSY;
- }
+
memset(cmd_request, 0, sizeof(struct storvsc_cmd_request));
/* Setup the cmd request */
@@ -1227,7 +1223,6 @@ static int storvsc_queuecommand_lck(struct scsi_cmnd *scmnd,
create_bounce_buffer(sgl, scsi_sg_count(scmnd),
scsi_bufflen(scmnd));
if (!cmd_request->bounce_sgl) {
- scmnd->scsi_done = NULL;
scmnd->host_scribble = NULL;
mempool_free(cmd_request,
host_dev->request_mempool);
@@ -1274,7 +1269,6 @@ retry_request:
mempool_free(cmd_request, host_dev->request_mempool);
- scmnd->scsi_done = NULL;
scmnd->host_scribble = NULL;
ret = SCSI_MLQUEUE_DEVICE_BUSY;
@@ -1283,9 +1277,6 @@ retry_request:
return ret;
}
-static DEF_SCSI_QCMD(storvsc_queuecommand)
-
-
/* Scsi driver */
static struct scsi_host_template scsi_driver = {
.module = THIS_MODULE,
--
1.7.4.1
^ permalink raw reply related
* [PATCH 05/11] Staging: hv: storvsc: Use the accessor function shost_priv()
From: K. Y. Srinivasan @ 2011-11-08 17:01 UTC (permalink / raw)
To: gregkh, linux-kernel, devel, virtualization, ohering,
James.Bottomley, hch
Cc: Haiyang Zhang
In-Reply-To: <1320771710-29139-1-git-send-email-kys@microsoft.com>
Use the accessor function shost_priv().
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
---
drivers/staging/hv/storvsc_drv.c | 14 +++++---------
1 files changed, 5 insertions(+), 9 deletions(-)
diff --git a/drivers/staging/hv/storvsc_drv.c b/drivers/staging/hv/storvsc_drv.c
index a145245..b21e85f 100644
--- a/drivers/staging/hv/storvsc_drv.c
+++ b/drivers/staging/hv/storvsc_drv.c
@@ -968,8 +968,7 @@ static int storvsc_remove(struct hv_device *dev)
{
struct storvsc_device *stor_device = hv_get_drvdata(dev);
struct Scsi_Host *host = stor_device->host;
- struct hv_host_device *host_dev =
- (struct hv_host_device *)host->hostdata;
+ struct hv_host_device *host_dev = shost_priv(host);
scsi_remove_host(host);
@@ -1057,8 +1056,7 @@ static int storvsc_host_reset(struct hv_device *device)
*/
static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd)
{
- struct hv_host_device *host_dev =
- (struct hv_host_device *)scmnd->device->host->hostdata;
+ struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
struct hv_device *dev = host_dev->dev;
return storvsc_host_reset(dev);
@@ -1073,8 +1071,7 @@ static void storvsc_command_completion(struct hv_storvsc_request *request)
struct storvsc_cmd_request *cmd_request =
(struct storvsc_cmd_request *)request->context;
struct scsi_cmnd *scmnd = cmd_request->cmd;
- struct hv_host_device *host_dev =
- (struct hv_host_device *)scmnd->device->host->hostdata;
+ struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
void (*scsi_done_fn)(struct scsi_cmnd *);
struct scsi_sense_hdr sense_hdr;
struct vmscsi_request *vm_srb;
@@ -1144,8 +1141,7 @@ static int storvsc_queuecommand_lck(struct scsi_cmnd *scmnd,
void (*done)(struct scsi_cmnd *))
{
int ret;
- struct hv_host_device *host_dev =
- (struct hv_host_device *)scmnd->device->host->hostdata;
+ struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
struct hv_device *dev = host_dev->dev;
struct hv_storvsc_request *request;
struct storvsc_cmd_request *cmd_request;
@@ -1359,7 +1355,7 @@ static int storvsc_probe(struct hv_device *device,
if (!host)
return -ENOMEM;
- host_dev = (struct hv_host_device *)host->hostdata;
+ host_dev = shost_priv(host);
memset(host_dev, 0, sizeof(struct hv_host_device));
host_dev->port = host->host_no;
--
1.7.4.1
^ permalink raw reply related
* [PATCH 04/11] Staging: hv: storvsc: Fix error handling storvsc_host_reset()
From: K. Y. Srinivasan @ 2011-11-08 17:01 UTC (permalink / raw)
To: gregkh, linux-kernel, devel, virtualization, ohering,
James.Bottomley, hch
Cc: Haiyang Zhang
In-Reply-To: <1320771710-29139-1-git-send-email-kys@microsoft.com>
Fix error handling storvsc_host_reset(). I would like to thank
Long Li <longli@microsoft.com> for reporting this.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Reported-by: Long Li <longli@microsoft.com>
---
drivers/staging/hv/storvsc_drv.c | 20 ++++++--------------
1 files changed, 6 insertions(+), 14 deletions(-)
diff --git a/drivers/staging/hv/storvsc_drv.c b/drivers/staging/hv/storvsc_drv.c
index e16c7a3..a145245 100644
--- a/drivers/staging/hv/storvsc_drv.c
+++ b/drivers/staging/hv/storvsc_drv.c
@@ -1019,7 +1019,7 @@ static int storvsc_host_reset(struct hv_device *device)
stor_device = get_out_stor_device(device);
if (!stor_device)
- return -ENODEV;
+ return FAILED;
request = &stor_device->reset_request;
vstor_packet = &request->vstor_packet;
@@ -1036,13 +1036,11 @@ static int storvsc_host_reset(struct hv_device *device)
VM_PKT_DATA_INBAND,
VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
if (ret != 0)
- goto cleanup;
+ return FAILED;
t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
- if (t == 0) {
- ret = -ETIMEDOUT;
- goto cleanup;
- }
+ if (t == 0)
+ return TIMEOUT_ERROR;
/*
@@ -1050,8 +1048,7 @@ static int storvsc_host_reset(struct hv_device *device)
* should have been flushed out and return to us
*/
-cleanup:
- return ret;
+ return SUCCESS;
}
@@ -1060,16 +1057,11 @@ cleanup:
*/
static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd)
{
- int ret;
struct hv_host_device *host_dev =
(struct hv_host_device *)scmnd->device->host->hostdata;
struct hv_device *dev = host_dev->dev;
- ret = storvsc_host_reset(dev);
- if (ret != 0)
- return ret;
-
- return ret;
+ return storvsc_host_reset(dev);
}
--
1.7.4.1
^ permalink raw reply related
* [PATCH 03/11] Staging: hv: storvsc: Fixup the error when processing SET_WINDOW command
From: K. Y. Srinivasan @ 2011-11-08 17:01 UTC (permalink / raw)
To: gregkh, linux-kernel, devel, virtualization, ohering,
James.Bottomley, hch
Cc: Haiyang Zhang
In-Reply-To: <1320771710-29139-1-git-send-email-kys@microsoft.com>
Fixup the error when processing SET_WINDOW command.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
---
drivers/staging/hv/storvsc_drv.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/drivers/staging/hv/storvsc_drv.c b/drivers/staging/hv/storvsc_drv.c
index a72cc22..e16c7a3 100644
--- a/drivers/staging/hv/storvsc_drv.c
+++ b/drivers/staging/hv/storvsc_drv.c
@@ -1136,7 +1136,7 @@ static bool storvsc_check_scsi_cmd(struct scsi_cmnd *scmnd)
switch (scsi_op) {
/* smartd sends this command, which will offline the device */
case SET_WINDOW:
- scmnd->result = DID_ERROR << 16;
+ scmnd->result = ILLEGAL_REQUEST << 16;
allowed = false;
break;
default:
--
1.7.4.1
^ permalink raw reply related
* [PATCH 02/11] Staging: hv: storvsc: Cleanup error handling in the probe function
From: K. Y. Srinivasan @ 2011-11-08 17:01 UTC (permalink / raw)
To: gregkh, linux-kernel, devel, virtualization, ohering,
James.Bottomley, hch
Cc: K. Y. Srinivasan, Haiyang Zhang
In-Reply-To: <1320771710-29139-1-git-send-email-kys@microsoft.com>
Cleanup error handling in the probe function.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
---
drivers/staging/hv/storvsc_drv.c | 42 +++++++++++++++++++++----------------
1 files changed, 24 insertions(+), 18 deletions(-)
diff --git a/drivers/staging/hv/storvsc_drv.c b/drivers/staging/hv/storvsc_drv.c
index 6a255e9..a72cc22 100644
--- a/drivers/staging/hv/storvsc_drv.c
+++ b/drivers/staging/hv/storvsc_drv.c
@@ -1388,17 +1388,14 @@ static int storvsc_probe(struct hv_device *device,
host_dev->request_pool);
if (!host_dev->request_mempool) {
- kmem_cache_destroy(host_dev->request_pool);
- scsi_host_put(host);
- return -ENOMEM;
+ ret = -ENOMEM;
+ goto err_out0;
}
stor_device = kzalloc(sizeof(struct storvsc_device), GFP_KERNEL);
if (!stor_device) {
- mempool_destroy(host_dev->request_mempool);
- kmem_cache_destroy(host_dev->request_pool);
- scsi_host_put(host);
- return -ENOMEM;
+ ret = -ENOMEM;
+ goto err_out1;
}
stor_device->destroy = false;
@@ -1409,13 +1406,8 @@ static int storvsc_probe(struct hv_device *device,
stor_device->port_number = host->host_no;
ret = storvsc_connect_to_vsp(device, storvsc_ringbuffer_size);
- if (ret) {
- mempool_destroy(host_dev->request_mempool);
- kmem_cache_destroy(host_dev->request_pool);
- scsi_host_put(host);
- kfree(stor_device);
- return ret;
- }
+ if (ret)
+ goto err_out2;
if (dev_is_ide)
storvsc_get_ide_info(device, &target, &path);
@@ -1435,7 +1427,7 @@ static int storvsc_probe(struct hv_device *device,
/* Register the HBA and start the scsi bus scan */
ret = scsi_add_host(host, &device->device);
if (ret != 0)
- goto err_out;
+ goto err_out3;
if (!dev_is_ide) {
scsi_scan_host(host);
@@ -1444,16 +1436,30 @@ static int storvsc_probe(struct hv_device *device,
ret = scsi_add_device(host, 0, target, 0);
if (ret) {
scsi_remove_host(host);
- goto err_out;
+ goto err_out3;
}
return 0;
-err_out:
+err_out3:
+ /*
+ * Once we have connected with the host, we would need to
+ * to invoke storvsc_dev_remove() to rollback this state and
+ * this call also frees up the stor_device; hence the jump around
+ * err_out2 label.
+ */
storvsc_dev_remove(device);
+ goto err_out1;
+
+err_out2:
+ kfree(stor_device);
+
+err_out1:
mempool_destroy(host_dev->request_mempool);
+
+err_out0:
kmem_cache_destroy(host_dev->request_pool);
scsi_host_put(host);
- return -ENODEV;
+ return ret;
}
/* The one and only one */
--
1.7.4.1
^ permalink raw reply related
* [PATCH 01/11] Staging: hv: storvsc: Use mempools to allocate struct storvsc_cmd_request
From: K. Y. Srinivasan @ 2011-11-08 17:01 UTC (permalink / raw)
To: gregkh, linux-kernel, devel, virtualization, ohering,
James.Bottomley, hch
Cc: K. Y. Srinivasan, Haiyang Zhang
In-Reply-To: <1320771677-29095-1-git-send-email-kys@microsoft.com>
We intend to use the storage driver to manage the root device.
To avoid deadlocks, use mempools to allocate struct storvsc_cmd_request.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
---
drivers/staging/hv/storvsc_drv.c | 30 +++++++++++++++++++++++++-----
1 files changed, 25 insertions(+), 5 deletions(-)
diff --git a/drivers/staging/hv/storvsc_drv.c b/drivers/staging/hv/storvsc_drv.c
index ae8c33e..6a255e9 100644
--- a/drivers/staging/hv/storvsc_drv.c
+++ b/drivers/staging/hv/storvsc_drv.c
@@ -32,6 +32,7 @@
#include <linux/module.h>
#include <linux/device.h>
#include <linux/hyperv.h>
+#include <linux/mempool.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_host.h>
@@ -42,6 +43,7 @@
#include <scsi/scsi_dbg.h>
+#define STORVSC_MIN_BUF_NR 64
#define STORVSC_RING_BUFFER_SIZE (20*PAGE_SIZE)
static int storvsc_ringbuffer_size = STORVSC_RING_BUFFER_SIZE;
@@ -287,6 +289,7 @@ struct storvsc_device {
struct hv_host_device {
struct hv_device *dev;
struct kmem_cache *request_pool;
+ mempool_t *request_mempool;
unsigned int port;
unsigned char path;
unsigned char target;
@@ -974,8 +977,10 @@ static int storvsc_remove(struct hv_device *dev)
storvsc_dev_remove(dev);
if (host_dev->request_pool) {
+ mempool_destroy(host_dev->request_mempool);
kmem_cache_destroy(host_dev->request_pool);
host_dev->request_pool = NULL;
+ host_dev->request_mempool = NULL;
}
return 0;
}
@@ -1120,7 +1125,7 @@ static void storvsc_command_completion(struct hv_storvsc_request *request)
scsi_done_fn(scmnd);
- kmem_cache_free(host_dev->request_pool, cmd_request);
+ mempool_free(cmd_request, host_dev->request_mempool);
}
static bool storvsc_check_scsi_cmd(struct scsi_cmnd *scmnd)
@@ -1176,12 +1181,13 @@ static int storvsc_queuecommand_lck(struct scsi_cmnd *scmnd,
request_size = sizeof(struct storvsc_cmd_request);
- cmd_request = kmem_cache_zalloc(host_dev->request_pool,
+ cmd_request = mempool_alloc(host_dev->request_mempool,
GFP_ATOMIC);
if (!cmd_request) {
scmnd->scsi_done = NULL;
return SCSI_MLQUEUE_DEVICE_BUSY;
}
+ memset(cmd_request, 0, sizeof(struct storvsc_cmd_request));
/* Setup the cmd request */
cmd_request->bounce_sgl_count = 0;
@@ -1235,8 +1241,8 @@ static int storvsc_queuecommand_lck(struct scsi_cmnd *scmnd,
if (!cmd_request->bounce_sgl) {
scmnd->scsi_done = NULL;
scmnd->host_scribble = NULL;
- kmem_cache_free(host_dev->request_pool,
- cmd_request);
+ mempool_free(cmd_request,
+ host_dev->request_mempool);
return SCSI_MLQUEUE_HOST_BUSY;
}
@@ -1278,7 +1284,7 @@ retry_request:
destroy_bounce_buffer(cmd_request->bounce_sgl,
cmd_request->bounce_sgl_count);
- kmem_cache_free(host_dev->request_pool, cmd_request);
+ mempool_free(cmd_request, host_dev->request_mempool);
scmnd->scsi_done = NULL;
scmnd->host_scribble = NULL;
@@ -1348,6 +1354,7 @@ static int storvsc_probe(struct hv_device *device,
const struct hv_vmbus_device_id *dev_id)
{
int ret;
+ int number = STORVSC_MIN_BUF_NR;
struct Scsi_Host *host;
struct hv_host_device *host_dev;
bool dev_is_ide = ((dev_id->driver_data == IDE_GUID) ? true : false);
@@ -1376,8 +1383,19 @@ static int storvsc_probe(struct hv_device *device,
return -ENOMEM;
}
+ host_dev->request_mempool = mempool_create(number, mempool_alloc_slab,
+ mempool_free_slab,
+ host_dev->request_pool);
+
+ if (!host_dev->request_mempool) {
+ kmem_cache_destroy(host_dev->request_pool);
+ scsi_host_put(host);
+ return -ENOMEM;
+ }
+
stor_device = kzalloc(sizeof(struct storvsc_device), GFP_KERNEL);
if (!stor_device) {
+ mempool_destroy(host_dev->request_mempool);
kmem_cache_destroy(host_dev->request_pool);
scsi_host_put(host);
return -ENOMEM;
@@ -1392,6 +1410,7 @@ static int storvsc_probe(struct hv_device *device,
stor_device->port_number = host->host_no;
ret = storvsc_connect_to_vsp(device, storvsc_ringbuffer_size);
if (ret) {
+ mempool_destroy(host_dev->request_mempool);
kmem_cache_destroy(host_dev->request_pool);
scsi_host_put(host);
kfree(stor_device);
@@ -1431,6 +1450,7 @@ static int storvsc_probe(struct hv_device *device,
err_out:
storvsc_dev_remove(device);
+ mempool_destroy(host_dev->request_mempool);
kmem_cache_destroy(host_dev->request_pool);
scsi_host_put(host);
return -ENODEV;
--
1.7.4.1
^ permalink raw reply related
* [PATCH 0000/0011] Staging: hv: storvsc cleanup/new features
From: K. Y. Srinivasan @ 2011-11-08 17:01 UTC (permalink / raw)
To: gregkh, linux-kernel, devel, virtualization, ohering,
James.Bottomley, hch
Cc: K. Y. Srinivasan
Cleanup storvsc based on review comments from James and
implement a couple of new features:
1) The bulk of this patch-set addresses the review comments by James.
James, the last time I had posted the patch to move the storage
driver out of staging, you wanted to wait until Greg's tree had
percolated up. Now, Greg's staging/hv has been merged up. Do you
now want me to re-post the patch to move the storage driver
out of staging? Let me know.
2) I have also implemented the feature to support hot add/remove
of devices configured under the scsi controller on the host.
Regards,
K. Y
^ permalink raw reply
* RE: [PATCH 0000/0011] Staging: hv: storvsc cleanup/new features
From: KY Srinivasan @ 2011-11-08 16:46 UTC (permalink / raw)
To: James Bottomley
Cc: gregkh@suse.de, linux-kernel@vger.kernel.org,
devel@linuxdriverproject.org, virtualization@lists.osdl.org,
ohering@suse.com, hch@infradead.org
In-Reply-To: <1320770370.2883.10.camel@dabdike.int.hansenpartnership.com>
> -----Original Message-----
> From: James Bottomley [mailto:James.Bottomley@HansenPartnership.com]
> Sent: Tuesday, November 08, 2011 11:40 AM
> To: KY Srinivasan
> Cc: gregkh@suse.de; linux-kernel@vger.kernel.org;
> devel@linuxdriverproject.org; virtualization@lists.osdl.org; ohering@suse.com;
> hch@infradead.org
> Subject: Re: [PATCH 0000/0011] Staging: hv: storvsc cleanup/new features
>
> On Tue, 2011-11-08 at 09:01 -0800, K. Y. Srinivasan wrote:
> > Cleanup storvsc based on review comments from James and
> > implement a couple of new features:
> >
> > 1) The bulk of this patch-set addresses the review comments by James.
> > James, the last time I had posted the patch to move the storage
> > driver out of staging, you wanted to wait until Greg's tree had
> > percolated up. Now, Greg's staging/hv has been merged up. Do you
> > now want me to re-post the patch to move the storage driver
> > out of staging? Let me know.
> >
> > 2) I have also implemented the feature to support hot add/remove
> > of devices configured under the scsi controller on the host.
>
> If you want scsi review on this, it should go to the scsi list:
>
> linux-scsi@vger.kernel.org
These patches are against Greg's current staging tree.
I was planning to send the patch that would move this driver out of staging
(that would include the cleanup patches I just sent out) to the scsi list. I am going
to send it out shortly.
Regards,
K. Y
^ permalink raw reply
* Re: [PATCH 0000/0011] Staging: hv: storvsc cleanup/new features
From: James Bottomley @ 2011-11-08 16:39 UTC (permalink / raw)
To: K. Y. Srinivasan
Cc: gregkh, linux-kernel, devel, virtualization, ohering, hch
In-Reply-To: <1320771677-29095-1-git-send-email-kys@microsoft.com>
On Tue, 2011-11-08 at 09:01 -0800, K. Y. Srinivasan wrote:
> Cleanup storvsc based on review comments from James and
> implement a couple of new features:
>
> 1) The bulk of this patch-set addresses the review comments by James.
> James, the last time I had posted the patch to move the storage
> driver out of staging, you wanted to wait until Greg's tree had
> percolated up. Now, Greg's staging/hv has been merged up. Do you
> now want me to re-post the patch to move the storage driver
> out of staging? Let me know.
>
> 2) I have also implemented the feature to support hot add/remove
> of devices configured under the scsi controller on the host.
If you want scsi review on this, it should go to the scsi list:
linux-scsi@vger.kernel.org
James
^ permalink raw reply
* Re: virtio-pci new configuration proposal
From: Sasha Levin @ 2011-11-08 14:15 UTC (permalink / raw)
To: Rusty Russell
Cc: Anthony Liguori, virtualization, linux-kernel, kvm,
Michael S. Tsirkin
In-Reply-To: <87aa87sd4y.fsf@rustcorp.com.au>
On Tue, Nov 8, 2011 at 1:53 AM, Rusty Russell <rusty@rustcorp.com.au> wrote:
> On Mon, 7 Nov 2011 23:14:14 +0200, "Michael S. Tsirkin" <mst@redhat.com> wrote:
>> On Mon, Nov 07, 2011 at 03:46:23PM +1030, Rusty Russell wrote:
>> > So far, the only three things make sense to have in a capability list:
>> > MSI-X, the upper 32 feature bits, and the per-device config.
>>
>> You mean the queue # to MSI-X vector mapping?
>
> Yep.
>
>> One thing to remember is that it must be in the same type of BAR as
>> the queue selection, since by PCI rules MMIO writes aren't I think
>> ordered with PIO writes (it doesn't matter with KVM but might
>> with another hypervisor).
>
> OK, I'm slowly getting up to speed.
>
> Next dumb q: Sasha, why did you introduce the idea of a separate
> virtio-pci capability list, rather than just using PCI capabilities
> directly? ie. instead of VIRTIO_PCI_C_LAYOUT, have VIRTIO_PCI_CORE,
> VIRTIO_PCI_MSIX, VIRTIO_PCI_DEV_SPECIFIC?
>
> Is it because we really want this stuff outside the PCI configuration
> space? Even so, should we just use the PCI cap list, and have each
> cap entry just contain a BIR & offset?
Mostly so that we can have the configuration out of PCI space so that
we can grow it later on.
We can go with doing it in PCI space with BIR & offset, yes.
^ permalink raw reply
* Re: [PATCH RFC 0/3] Support multiple VirtioConsoles.
From: Amit Shah @ 2011-11-08 11:00 UTC (permalink / raw)
To: Miche Baker-Harvey
Cc: Stephen Rothwell, Greg Kroah-Hartman, Konrad Rzeszutek Wilk,
Benjamin Herrenschmidt, linux-kernel, Mike Waychison, xen-devel,
Anton Blanchard, virtualization, ppc-dev
In-Reply-To: <20111102221905.9722.62090.stgit@miche.sea.corp.google.com>
On (Wed) 02 Nov 2011 [15:19:06], Miche Baker-Harvey wrote:
> This patchset applies to linux-next/next-20111102.
Did you forget to send out the patches? I don't see anything on any
of the lists nor my inbox.
Amit
^ permalink raw reply
* Re: virtio-pci new configuration proposal
From: Rusty Russell @ 2011-11-08 10:21 UTC (permalink / raw)
To: Michael S. Tsirkin
Cc: Anthony Liguori, virtualization, Sasha Levin, kvm, linux-kernel
In-Reply-To: <20111108063249.GB11577@redhat.com>
On Tue, 8 Nov 2011 08:32:50 +0200, "Michael S. Tsirkin" <mst@redhat.com> wrote:
> On Tue, Nov 08, 2011 at 10:23:33AM +1030, Rusty Russell wrote:
> > Even so, should we just use the PCI cap list, and have each
> > cap entry just contain a BIR & offset?
> >
> > Thanks,
> > Rusty.
>
> And size :)
> I say, Rusty, did you see my patch? That's what it's doing,
> I also addressed the issue that with KVM on x86, PIO is faster
> than MMIO so we need to use it for notifications/isr.
Faster? Really? Why? Were the ppc guys right that's it's obsolescent?
Because PIO is going to be ugly AFAICT for every non-x86 platform.
Cheers,
Rusty.
^ permalink raw reply
* Re: [PATCH] virtio-pci: fix use after free
From: Rusty Russell @ 2011-11-08 10:19 UTC (permalink / raw)
To: Amit Shah, Michael S. Tsirkin; +Cc: stable, linux-kernel, virtualization
In-Reply-To: <20111108054616.GC2068@amit-x200.redhat.com>
On Tue, 8 Nov 2011 11:16:16 +0530, Amit Shah <amit.shah@redhat.com> wrote:
> On (Mon) 07 Nov 2011 [18:37:05], Michael S. Tsirkin wrote:
> > Commit 31a3ddda166cda86d2b5111e09ba4bda5239fae6 introduced
> > a use after free in virtio-pci. The main issue is
> > that the release method signals removal of the virtio device,
> > while remove signals removal of the pci device.
> >
> > For example, on driver removal or hot-unplug,
> > virtio_pci_release_dev is called before virtio_pci_remove.
> > We then might get a crash as virtio_pci_remove tries to use the
> > device freed by virtio_pci_release_dev.
> >
> > We allocate/free all resources together with the
> > pci device, so we can leave the release method empty.
> >
> > Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
>
> Acked-by: Amit Shah <amit.shah@redhat.com>
>
> (note: Adding CC: stable@kernel.org to the commit log is the way
> patches get automatically pulled from upstream when committed; CC'ing
> stable on submissions won't help with that.)
Yeah, I fixed it though.
Cheers,
Rusty.
^ permalink raw reply
page: next (older) | prev (newer) | latest
- recent:[subjects (threaded)|topics (new)|topics (active)]
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox