Commit 9003a249 authored by Alexey Kardashevskiy's avatar Alexey Kardashevskiy Committed by Michael Ellerman

powerpc/powernv/ioda: Remove explicit max window size check

DMA windows can only have a size of power of two on IODA2 hardware and
using memory_hotplug_max() to determine the upper limit won't work
correcly if it returns not power of two value.

This removes the check as the platform code does this check in
pnv_pci_ioda2_setup_default_config() anyway; the other client is VFIO
and that thing checks against locked_vm limit which prevents the userspace
from locking too much memory.

It is expected to impact DPDK on machines with non-power-of-two RAM size,
mostly. KVM guests are less likely to be affected as usually guests get
less than half of hosts RAM.
Signed-off-by: default avatarAlexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
parent cd77b5ce
......@@ -2797,7 +2797,7 @@ static long pnv_pci_ioda2_table_alloc_pages(int nid, __u64 bus_offset,
if (!levels || (levels > POWERNV_IOMMU_MAX_LEVELS))
return -EINVAL;
if ((window_size > memory_hotplug_max()) || !is_power_of_2(window_size))
if (!is_power_of_2(window_size))
return -EINVAL;
/* Adjust direct table size from window_size and levels */
......
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