Not doing so is a bug and might trigger a BUG_ON in
handle_mm_fault(). So add the proper permission checks
before calling into mm code.
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Acked-By: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This is the downside of using bitfields in the struct definition, rather
than doing all the explicit masking and shifting.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Not entirely clear why, but it seems we need to reserve PASID zero and
flush it when we make a PASID entry present.
Quite we we couldn't use the true PASID value, isn't clear.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Change the 'pages' parameter to 'unsigned long' to avoid overflow.
Fix the device-IOTLB flush parameter calculation — the size of the IOTLB
flush is indicated by the position of the least significant zero bit in
the address field. For example, a value of 0x12345f000 will flush from
0x123440000 to 0x12347ffff (256KiB).
Finally, the cap_pgsel_inv() is not relevant to SVM; the spec says that
*all* implementations must support page-selective invaliation for
"first-level" translations. So don't check for it.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
There is an extra semi-colon on this if statement so we always break on
the first iteration.
Fixes: 0204a49609 ('iommu/vt-d: Add callback to device driver on page faults')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
This really should be VTD_PAGE_SHIFT, not PAGE_SHIFT. Not that we ever
really anticipate seeing this used on IA64, but we should get it right
anyway.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
The "req->addr" variable is a bit field declared as "u64 addr:52;".
The "address" variable is a u64. We need to cast "req->addr" to a u64
before the shift or the result is truncated to 52 bits.
Fixes: a222a7f0bb ('iommu/vt-d: Implement page request handling')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Dan Carpenter pointed out an error path which could lead to us
dereferencing the 'svm' pointer after we know it to be NULL because the
PASID lookup failed. Fix that, and make it less likely to happen again.
Fixes: a222a7f0bb ('iommu/vt-d: Implement page request handling')
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
This is only usable for the static 1:1 mapping of physical memory.
Any access to vmalloc or module regions will require some way of doing
an IOTLB flush. It's theoretically possible to hook into the
tlb_flush_kernel_range() function, but that seems like overkill — most
of the addresses accessed through a kernel PASID *will* be in the 1:1
mapping.
If we really need to allow access to more interesting kernel regions,
then the answer will probably be an explicit IOTLB flush call after use,
akin to the DMA API's unmap function.
In fact, it might be worth introducing that sooner rather than later, and
making it just BUG() if the address isn't in the static 1:1 mapping.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
This provides basic PASID support for endpoint devices, tested with a
version of the i915 driver.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
