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authorEric Farman <farman@linux.ibm.com>2019-05-16 18:14:03 +0200
committerCornelia Huck <cohuck@redhat.com>2019-06-03 12:02:55 +0200
commit9b6e57e5a51696171de990b3c41bd53d4b8ab8ac (patch)
tree1c8eb0b1fe09b72cf400a17ec5b8419258ef45a8 /arch/s390/Kconfig
parents390/cio: Allow zero-length CCWs in vfio-ccw (diff)
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s390/cio: Remove vfio-ccw checks of command codes
If the CCW being processed is a No-Operation, then by definition no data is being transferred. Let's fold those checks into the normal CCW processors, rather than skipping out early. Likewise, if the CCW being processed is a "test" (a category defined here as an opcode that contains zero in the lowest four bits) then no special processing is necessary as far as vfio-ccw is concerned. These command codes have not been valid since the S/370 days, meaning they are invalid in the same way as one that ends in an eight [1] or an otherwise valid command code that is undefined for the device type in question. Considering that, let's just process "test" CCWs like any other CCW, and send everything to the hardware. [1] POPS states that a x08 is a TIC CCW, and that having any high-order bits enabled is invalid for format-1 CCWs. For format-0 CCWs, the high-order bits are ignored. Signed-off-by: Eric Farman <farman@linux.ibm.com> Message-Id: <20190516161403.79053-4-farman@linux.ibm.com> Acked-by: Farhan Ali <alifm@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Diffstat (limited to 'arch/s390/Kconfig')
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