powerpc/mm: Wire up hpte_removebolted for powernv
Adds support for removing bolted (i.e kernel linear mapping) mappings on
powernv. This is needed to support memory hot unplug operations which
are required for the teardown of DAX/PMEM devices.
Reviewed-by: Balbir Singh <bsingharora@gmail.com>
Reviewed-by: Rashmica Gupta <rashmica.g@gmail.com>
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
diff --git a/arch/powerpc/mm/hash_native_64.c b/arch/powerpc/mm/hash_native_64.c
index fbd1acc..3848af1 100644
--- a/arch/powerpc/mm/hash_native_64.c
+++ b/arch/powerpc/mm/hash_native_64.c
@@ -413,6 +413,38 @@
tlbie(vpn, psize, psize, ssize, 0);
}
+/*
+ * Remove a bolted kernel entry. Memory hotplug uses this.
+ *
+ * No need to lock here because we should be the only user.
+ */
+static int native_hpte_removebolted(unsigned long ea, int psize, int ssize)
+{
+ unsigned long vpn;
+ unsigned long vsid;
+ long slot;
+ struct hash_pte *hptep;
+
+ vsid = get_kernel_vsid(ea, ssize);
+ vpn = hpt_vpn(ea, vsid, ssize);
+
+ slot = native_hpte_find(vpn, psize, ssize);
+ if (slot == -1)
+ return -ENOENT;
+
+ hptep = htab_address + slot;
+
+ VM_WARN_ON(!(be64_to_cpu(hptep->v) & HPTE_V_BOLTED));
+
+ /* Invalidate the hpte */
+ hptep->v = 0;
+
+ /* Invalidate the TLB */
+ tlbie(vpn, psize, psize, ssize, 0);
+ return 0;
+}
+
+
static void native_hpte_invalidate(unsigned long slot, unsigned long vpn,
int bpsize, int apsize, int ssize, int local)
{
@@ -731,6 +763,7 @@
mmu_hash_ops.hpte_invalidate = native_hpte_invalidate;
mmu_hash_ops.hpte_updatepp = native_hpte_updatepp;
mmu_hash_ops.hpte_updateboltedpp = native_hpte_updateboltedpp;
+ mmu_hash_ops.hpte_removebolted = native_hpte_removebolted;
mmu_hash_ops.hpte_insert = native_hpte_insert;
mmu_hash_ops.hpte_remove = native_hpte_remove;
mmu_hash_ops.hpte_clear_all = native_hpte_clear;