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author | Stephen Hemminger <stephen@networkplumber.org> | 2018-01-09 21:57:32 +0100 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-01-10 17:40:53 +0100 |
commit | ca3cda6fcf1e922213a0cc58e708ffb999151db3 (patch) | |
tree | 9c05b3efcc9058c9e26116711e034253996dea6b /Documentation | |
parent | uio_hv_generic: check that host supports monitor page (diff) | |
download | linux-ca3cda6fcf1e922213a0cc58e708ffb999151db3.tar.xz linux-ca3cda6fcf1e922213a0cc58e708ffb999151db3.zip |
uio_hv_generic: add rescind support
When host rescinds the device, the UIO driver will clear the interrupt
state and notify application. The read (or write) on the interrupt FD
will then fail with -EIO. This is simpler than adding lots extra uevent
stuff inside UIO.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/driver-api/uio-howto.rst | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/Documentation/driver-api/uio-howto.rst b/Documentation/driver-api/uio-howto.rst index 97e6435b3934..693e3bd84e79 100644 --- a/Documentation/driver-api/uio-howto.rst +++ b/Documentation/driver-api/uio-howto.rst @@ -698,6 +698,10 @@ prevents the device from generating further interrupts until the bit is cleared. The userspace driver should clear this bit before blocking and waiting for more interrupts. +When host rescinds a device, the interrupt file descriptor is marked down +and any reads of the interrupt file descriptor will return -EIO. Similar +to a closed socket or disconnected serial device. + The vmbus device regions are mapped into uio device resources: 0) Channel ring buffers: guest to host and host to guest 1) Guest to host interrupt signalling pages |