1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * CoProcessor (SPU/AFU) mm fault handler 4 * 5 * (C) Copyright IBM Deutschland Entwicklung GmbH 2007 6 * 7 * Author: Arnd Bergmann <arndb@de.ibm.com> 8 * Author: Jeremy Kerr <jk@ozlabs.org> 9 */ 10 #include <linux/sched.h> 11 #include <linux/mm.h> 12 #include <linux/export.h> 13 #include <asm/reg.h> 14 #include <asm/copro.h> 15 #include <asm/spu.h> 16 #include <misc/cxl-base.h> 17 18 /* 19 * This ought to be kept in sync with the powerpc specific do_page_fault 20 * function. Currently, there are a few corner cases that we haven't had 21 * to handle fortunately. 22 */ 23 int copro_handle_mm_fault(struct mm_struct *mm, unsigned long ea, 24 unsigned long dsisr, vm_fault_t *flt) 25 { 26 struct vm_area_struct *vma; 27 unsigned long is_write; 28 int ret; 29 30 if (mm == NULL) 31 return -EFAULT; 32 33 if (mm->pgd == NULL) 34 return -EFAULT; 35 36 vma = lock_mm_and_find_vma(mm, ea, NULL); 37 if (!vma) 38 return -EFAULT; 39 40 ret = -EFAULT; 41 is_write = dsisr & DSISR_ISSTORE; 42 if (is_write) { 43 if (!(vma->vm_flags & VM_WRITE)) 44 goto out_unlock; 45 } else { 46 if (!(vma->vm_flags & (VM_READ | VM_EXEC))) 47 goto out_unlock; 48 /* 49 * PROT_NONE is covered by the VMA check above. 50 * and hash should get a NOHPTE fault instead of 51 * a PROTFAULT in case fixup is needed for things 52 * like autonuma. 53 */ 54 if (!radix_enabled()) 55 WARN_ON_ONCE(dsisr & DSISR_PROTFAULT); 56 } 57 58 ret = 0; 59 *flt = handle_mm_fault(vma, ea, is_write ? FAULT_FLAG_WRITE : 0, NULL); 60 61 /* The fault is fully completed (including releasing mmap lock) */ 62 if (*flt & VM_FAULT_COMPLETED) 63 return 0; 64 65 if (unlikely(*flt & VM_FAULT_ERROR)) { 66 if (*flt & VM_FAULT_OOM) { 67 ret = -ENOMEM; 68 goto out_unlock; 69 } else if (*flt & (VM_FAULT_SIGBUS | VM_FAULT_SIGSEGV)) { 70 ret = -EFAULT; 71 goto out_unlock; 72 } 73 BUG(); 74 } 75 76 out_unlock: 77 mmap_read_unlock(mm); 78 return ret; 79 } 80 EXPORT_SYMBOL_GPL(copro_handle_mm_fault); 81 82 #ifdef CONFIG_PPC_64S_HASH_MMU 83 int copro_calculate_slb(struct mm_struct *mm, u64 ea, struct copro_slb *slb) 84 { 85 u64 vsid, vsidkey; 86 int psize, ssize; 87 88 switch (get_region_id(ea)) { 89 case USER_REGION_ID: 90 pr_devel("%s: 0x%llx -- USER_REGION_ID\n", __func__, ea); 91 if (mm == NULL) 92 return 1; 93 psize = get_slice_psize(mm, ea); 94 ssize = user_segment_size(ea); 95 vsid = get_user_vsid(&mm->context, ea, ssize); 96 vsidkey = SLB_VSID_USER; 97 break; 98 case VMALLOC_REGION_ID: 99 pr_devel("%s: 0x%llx -- VMALLOC_REGION_ID\n", __func__, ea); 100 psize = mmu_vmalloc_psize; 101 ssize = mmu_kernel_ssize; 102 vsid = get_kernel_vsid(ea, mmu_kernel_ssize); 103 vsidkey = SLB_VSID_KERNEL; 104 break; 105 case IO_REGION_ID: 106 pr_devel("%s: 0x%llx -- IO_REGION_ID\n", __func__, ea); 107 psize = mmu_io_psize; 108 ssize = mmu_kernel_ssize; 109 vsid = get_kernel_vsid(ea, mmu_kernel_ssize); 110 vsidkey = SLB_VSID_KERNEL; 111 break; 112 case LINEAR_MAP_REGION_ID: 113 pr_devel("%s: 0x%llx -- LINEAR_MAP_REGION_ID\n", __func__, ea); 114 psize = mmu_linear_psize; 115 ssize = mmu_kernel_ssize; 116 vsid = get_kernel_vsid(ea, mmu_kernel_ssize); 117 vsidkey = SLB_VSID_KERNEL; 118 break; 119 default: 120 pr_debug("%s: invalid region access at %016llx\n", __func__, ea); 121 return 1; 122 } 123 /* Bad address */ 124 if (!vsid) 125 return 1; 126 127 vsid = (vsid << slb_vsid_shift(ssize)) | vsidkey; 128 129 vsid |= mmu_psize_defs[psize].sllp | 130 ((ssize == MMU_SEGSIZE_1T) ? SLB_VSID_B_1T : 0); 131 132 slb->esid = (ea & (ssize == MMU_SEGSIZE_1T ? ESID_MASK_1T : ESID_MASK)) | SLB_ESID_V; 133 slb->vsid = vsid; 134 135 return 0; 136 } 137 EXPORT_SYMBOL_GPL(copro_calculate_slb); 138 139 void copro_flush_all_slbs(struct mm_struct *mm) 140 { 141 #ifdef CONFIG_SPU_BASE 142 spu_flush_all_slbs(mm); 143 #endif 144 cxl_slbia(mm); 145 } 146 EXPORT_SYMBOL_GPL(copro_flush_all_slbs); 147 #endif 148