From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-x244.google.com (mail-pf0-x244.google.com [IPv6:2607:f8b0:400e:c00::244]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3wX24d33DmzDqZc for ; Tue, 23 May 2017 14:05:37 +1000 (AEST) Received: by mail-pf0-x244.google.com with SMTP id n23so24475445pfb.3 for ; Mon, 22 May 2017 21:05:37 -0700 (PDT) From: Oliver O'Halloran To: linuxppc-dev@lists.ozlabs.org Cc: linux-mm@kvack.org, Anton Blanchard , Oliver O'Halloran Subject: [PATCH 1/6] powerpc/mm: Wire up hpte_removebolted for powernv Date: Tue, 23 May 2017 14:05:19 +1000 Message-Id: <20170523040524.13717-1-oohall@gmail.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Anton Blanchard 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: Rashmica Gupta Signed-off-by: Anton Blanchard Signed-off-by: Oliver O'Halloran --- v1 -> v2: Fixed the commit author Added VM_WARN_ON() if we attempt to remove an unbolted hpte --- arch/powerpc/mm/hash_native_64.c | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) diff --git a/arch/powerpc/mm/hash_native_64.c b/arch/powerpc/mm/hash_native_64.c index 65bb8f33b399..b534d041cfe8 100644 --- a/arch/powerpc/mm/hash_native_64.c +++ b/arch/powerpc/mm/hash_native_64.c @@ -407,6 +407,38 @@ static void native_hpte_updateboltedpp(unsigned long newpp, unsigned long ea, 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) { @@ -725,6 +757,7 @@ void __init hpte_init_native(void) 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; -- 2.9.3