From 76cb841cb886eef6b3bee341a2266c76578724ad Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Mon, 6 May 2024 03:02:30 +0200 Subject: Adding upstream version 4.19.249. Signed-off-by: Daniel Baumann --- arch/powerpc/mm/hash64_64k.c | 333 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 333 insertions(+) create mode 100644 arch/powerpc/mm/hash64_64k.c (limited to 'arch/powerpc/mm/hash64_64k.c') diff --git a/arch/powerpc/mm/hash64_64k.c b/arch/powerpc/mm/hash64_64k.c new file mode 100644 index 000000000..3afa253d7 --- /dev/null +++ b/arch/powerpc/mm/hash64_64k.c @@ -0,0 +1,333 @@ +/* + * Copyright IBM Corporation, 2015 + * Author Aneesh Kumar K.V + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of version 2 of the GNU Lesser General Public License + * as published by the Free Software Foundation. + * + * This program is distributed in the hope that it would be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. + * + */ + +#include +#include +#include + +/* + * Return true, if the entry has a slot value which + * the software considers as invalid. + */ +static inline bool hpte_soft_invalid(unsigned long hidx) +{ + return ((hidx & 0xfUL) == 0xfUL); +} + +/* + * index from 0 - 15 + */ +bool __rpte_sub_valid(real_pte_t rpte, unsigned long index) +{ + return !(hpte_soft_invalid(__rpte_to_hidx(rpte, index))); +} + +int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid, + pte_t *ptep, unsigned long trap, unsigned long flags, + int ssize, int subpg_prot) +{ + real_pte_t rpte; + unsigned long hpte_group; + unsigned int subpg_index; + unsigned long rflags, pa; + unsigned long old_pte, new_pte, subpg_pte; + unsigned long vpn, hash, slot, gslot; + unsigned long shift = mmu_psize_defs[MMU_PAGE_4K].shift; + + /* + * atomically mark the linux large page PTE busy and dirty + */ + do { + pte_t pte = READ_ONCE(*ptep); + + old_pte = pte_val(pte); + /* If PTE busy, retry the access */ + if (unlikely(old_pte & H_PAGE_BUSY)) + return 0; + /* If PTE permissions don't match, take page fault */ + if (unlikely(!check_pte_access(access, old_pte))) + return 1; + /* + * Try to lock the PTE, add ACCESSED and DIRTY if it was + * a write access. Since this is 4K insert of 64K page size + * also add H_PAGE_COMBO + */ + new_pte = old_pte | H_PAGE_BUSY | _PAGE_ACCESSED | H_PAGE_COMBO; + if (access & _PAGE_WRITE) + new_pte |= _PAGE_DIRTY; + } while (!pte_xchg(ptep, __pte(old_pte), __pte(new_pte))); + + /* + * Handle the subpage protection bits + */ + subpg_pte = new_pte & ~subpg_prot; + rflags = htab_convert_pte_flags(subpg_pte); + + if (cpu_has_feature(CPU_FTR_NOEXECUTE) && + !cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) { + + /* + * No CPU has hugepages but lacks no execute, so we + * don't need to worry about that case + */ + rflags = hash_page_do_lazy_icache(rflags, __pte(old_pte), trap); + } + + subpg_index = (ea & (PAGE_SIZE - 1)) >> shift; + vpn = hpt_vpn(ea, vsid, ssize); + rpte = __real_pte(__pte(old_pte), ptep, PTRS_PER_PTE); + /* + *None of the sub 4k page is hashed + */ + if (!(old_pte & H_PAGE_HASHPTE)) + goto htab_insert_hpte; + /* + * Check if the pte was already inserted into the hash table + * as a 64k HW page, and invalidate the 64k HPTE if so. + */ + if (!(old_pte & H_PAGE_COMBO)) { + flush_hash_page(vpn, rpte, MMU_PAGE_64K, ssize, flags); + /* + * clear the old slot details from the old and new pte. + * On hash insert failure we use old pte value and we don't + * want slot information there if we have a insert failure. + */ + old_pte &= ~H_PAGE_HASHPTE; + new_pte &= ~H_PAGE_HASHPTE; + goto htab_insert_hpte; + } + /* + * Check for sub page valid and update + */ + if (__rpte_sub_valid(rpte, subpg_index)) { + int ret; + + gslot = pte_get_hash_gslot(vpn, shift, ssize, rpte, + subpg_index); + ret = mmu_hash_ops.hpte_updatepp(gslot, rflags, vpn, + MMU_PAGE_4K, MMU_PAGE_4K, + ssize, flags); + + /* + * If we failed because typically the HPTE wasn't really here + * we try an insertion. + */ + if (ret == -1) + goto htab_insert_hpte; + + *ptep = __pte(new_pte & ~H_PAGE_BUSY); + return 0; + } + +htab_insert_hpte: + + /* + * Initialize all hidx entries to invalid value, the first time + * the PTE is about to allocate a 4K HPTE. + */ + if (!(old_pte & H_PAGE_COMBO)) + rpte.hidx = INVALID_RPTE_HIDX; + + /* + * handle H_PAGE_4K_PFN case + */ + if (old_pte & H_PAGE_4K_PFN) { + /* + * All the sub 4k page have the same + * physical address. + */ + pa = pte_pfn(__pte(old_pte)) << HW_PAGE_SHIFT; + } else { + pa = pte_pfn(__pte(old_pte)) << PAGE_SHIFT; + pa += (subpg_index << shift); + } + hash = hpt_hash(vpn, shift, ssize); +repeat: + hpte_group = (hash & htab_hash_mask) * HPTES_PER_GROUP; + + /* Insert into the hash table, primary slot */ + slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa, rflags, 0, + MMU_PAGE_4K, MMU_PAGE_4K, ssize); + /* + * Primary is full, try the secondary + */ + if (unlikely(slot == -1)) { + bool soft_invalid; + + hpte_group = (~hash & htab_hash_mask) * HPTES_PER_GROUP; + slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa, + rflags, HPTE_V_SECONDARY, + MMU_PAGE_4K, MMU_PAGE_4K, + ssize); + + soft_invalid = hpte_soft_invalid(slot); + if (unlikely(soft_invalid)) { + /* + * We got a valid slot from a hardware point of view. + * but we cannot use it, because we use this special + * value; as defined by hpte_soft_invalid(), to track + * invalid slots. We cannot use it. So invalidate it. + */ + gslot = slot & _PTEIDX_GROUP_IX; + mmu_hash_ops.hpte_invalidate(hpte_group + gslot, vpn, + MMU_PAGE_4K, MMU_PAGE_4K, + ssize, 0); + } + + if (unlikely(slot == -1 || soft_invalid)) { + /* + * For soft invalid slot, let's ensure that we release a + * slot from the primary, with the hope that we will + * acquire that slot next time we try. This will ensure + * that we do not get the same soft-invalid slot. + */ + if (soft_invalid || (mftb() & 0x1)) + hpte_group = (hash & htab_hash_mask) * HPTES_PER_GROUP; + + mmu_hash_ops.hpte_remove(hpte_group); + /* + * FIXME!! Should be try the group from which we removed ? + */ + goto repeat; + } + } + /* + * Hypervisor failure. Restore old pte and return -1 + * similar to __hash_page_* + */ + if (unlikely(slot == -2)) { + *ptep = __pte(old_pte); + hash_failure_debug(ea, access, vsid, trap, ssize, + MMU_PAGE_4K, MMU_PAGE_4K, old_pte); + return -1; + } + + new_pte |= pte_set_hidx(ptep, rpte, subpg_index, slot, PTRS_PER_PTE); + new_pte |= H_PAGE_HASHPTE; + + *ptep = __pte(new_pte & ~H_PAGE_BUSY); + return 0; +} + +int __hash_page_64K(unsigned long ea, unsigned long access, + unsigned long vsid, pte_t *ptep, unsigned long trap, + unsigned long flags, int ssize) +{ + real_pte_t rpte; + unsigned long hpte_group; + unsigned long rflags, pa; + unsigned long old_pte, new_pte; + unsigned long vpn, hash, slot; + unsigned long shift = mmu_psize_defs[MMU_PAGE_64K].shift; + + /* + * atomically mark the linux large page PTE busy and dirty + */ + do { + pte_t pte = READ_ONCE(*ptep); + + old_pte = pte_val(pte); + /* If PTE busy, retry the access */ + if (unlikely(old_pte & H_PAGE_BUSY)) + return 0; + /* If PTE permissions don't match, take page fault */ + if (unlikely(!check_pte_access(access, old_pte))) + return 1; + /* + * Check if PTE has the cache-inhibit bit set + * If so, bail out and refault as a 4k page + */ + if (!mmu_has_feature(MMU_FTR_CI_LARGE_PAGE) && + unlikely(pte_ci(pte))) + return 0; + /* + * Try to lock the PTE, add ACCESSED and DIRTY if it was + * a write access. + */ + new_pte = old_pte | H_PAGE_BUSY | _PAGE_ACCESSED; + if (access & _PAGE_WRITE) + new_pte |= _PAGE_DIRTY; + } while (!pte_xchg(ptep, __pte(old_pte), __pte(new_pte))); + + rflags = htab_convert_pte_flags(new_pte); + rpte = __real_pte(__pte(old_pte), ptep, PTRS_PER_PTE); + + if (cpu_has_feature(CPU_FTR_NOEXECUTE) && + !cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) + rflags = hash_page_do_lazy_icache(rflags, __pte(old_pte), trap); + + vpn = hpt_vpn(ea, vsid, ssize); + if (unlikely(old_pte & H_PAGE_HASHPTE)) { + unsigned long gslot; + + /* + * There MIGHT be an HPTE for this pte + */ + gslot = pte_get_hash_gslot(vpn, shift, ssize, rpte, 0); + if (mmu_hash_ops.hpte_updatepp(gslot, rflags, vpn, MMU_PAGE_64K, + MMU_PAGE_64K, ssize, + flags) == -1) + old_pte &= ~_PAGE_HPTEFLAGS; + } + + if (likely(!(old_pte & H_PAGE_HASHPTE))) { + + pa = pte_pfn(__pte(old_pte)) << PAGE_SHIFT; + hash = hpt_hash(vpn, shift, ssize); + +repeat: + hpte_group = (hash & htab_hash_mask) * HPTES_PER_GROUP; + + /* Insert into the hash table, primary slot */ + slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa, rflags, 0, + MMU_PAGE_64K, MMU_PAGE_64K, + ssize); + /* + * Primary is full, try the secondary + */ + if (unlikely(slot == -1)) { + hpte_group = (~hash & htab_hash_mask) * HPTES_PER_GROUP; + slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa, + rflags, + HPTE_V_SECONDARY, + MMU_PAGE_64K, + MMU_PAGE_64K, ssize); + if (slot == -1) { + if (mftb() & 0x1) + hpte_group = (hash & htab_hash_mask) * + HPTES_PER_GROUP; + mmu_hash_ops.hpte_remove(hpte_group); + /* + * FIXME!! Should be try the group from which we removed ? + */ + goto repeat; + } + } + /* + * Hypervisor failure. Restore old pte and return -1 + * similar to __hash_page_* + */ + if (unlikely(slot == -2)) { + *ptep = __pte(old_pte); + hash_failure_debug(ea, access, vsid, trap, ssize, + MMU_PAGE_64K, MMU_PAGE_64K, old_pte); + return -1; + } + + new_pte = (new_pte & ~_PAGE_HPTEFLAGS) | H_PAGE_HASHPTE; + new_pte |= pte_set_hidx(ptep, rpte, 0, slot, PTRS_PER_PTE); + } + *ptep = __pte(new_pte & ~H_PAGE_BUSY); + return 0; +} -- cgit v1.2.3