When we are translating channel data addresses from guest to host
address space for TIC instructions we are getting incorrect
addresses because of a pointer arithmetic error.
We currently calculate the offset of the TIC's cda from the start
of the channel program chain (ccw->cda - ccw_head). We then add
that to the address of the ccw chain in host memory (iter->ch_ccw).
The problem is that iter->ch_ccw is a pointer to struct ccw1 so
when we increment it we are actually incrementing by the size of
struct ccw1 which is 8 bytes. The intent was to increment by
n-bytes, not n*8.
The fix: cast iter->ch_ccw to char* so it will be incremented by
n*1.
Reviewed-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Jason J. Herne <jjherne@linux.vnet.ibm.com>
Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Message-Id: <20170721011436.76112-1-bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Although Linux does not use format-0 channel command words (CCW0)
these are a non-optional part of the platform spec, and for the sake
of platform compliance, and possibly some non-Linux guests, we have
to support CCW0.
Making the kernel execute a format 0 channel program is too much hassle
because we would need to allocate and use memory which can be addressed
by 24 bit physical addresses (because of CCW0.cda). So we implement CCW0
support by translating the channel program into an equivalent CCW1
program instead.
Based upon an orginal patch by Kai Yue Wang.
Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Message-Id: <20170317031743.40128-16-bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Introduce ccwchain structure and helper functions that can be used to
handle a channel program issued from a virtual machine.
The following limitations apply:
1. Supports only prefetch enabled mode.
2. Supports idal(c64) ccw chaining.
3. Supports 4k idaw.
4. Supports ccw1.
5. Supports direct ccw chaining by translating them to idal ccws.
CCW translation requires to leverage the vfio_(un)pin_pages interfaces
to pin/unpin sets of mem pages frequently. Currently we have a lack of
support to do this in an efficient way. So we introduce pfn_array data
structure and helper functions to handle pin/unpin operations here.
Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Message-Id: <20170317031743.40128-6-bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Jason J. Herne