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Release 4.14 arch/powerpc/kvm/book3s_64_vio.c

Directory: arch/powerpc/kvm
/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, version 2, as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 * Copyright 2010 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
 * Copyright 2011 David Gibson, IBM Corporation <dwg@au1.ibm.com>
 * Copyright 2016 Alexey Kardashevskiy, IBM Corporation <aik@au1.ibm.com>
 */

#include <linux/types.h>
#include <linux/string.h>
#include <linux/kvm.h>
#include <linux/kvm_host.h>
#include <linux/highmem.h>
#include <linux/gfp.h>
#include <linux/slab.h>
#include <linux/sched/signal.h>
#include <linux/hugetlb.h>
#include <linux/list.h>
#include <linux/anon_inodes.h>
#include <linux/iommu.h>
#include <linux/file.h>

#include <asm/tlbflush.h>
#include <asm/kvm_ppc.h>
#include <asm/kvm_book3s.h>
#include <asm/book3s/64/mmu-hash.h>
#include <asm/hvcall.h>
#include <asm/synch.h>
#include <asm/ppc-opcode.h>
#include <asm/kvm_host.h>
#include <asm/udbg.h>
#include <asm/iommu.h>
#include <asm/tce.h>
#include <asm/mmu_context.h>


static unsigned long kvmppc_tce_pages(unsigned long iommu_pages) { return ALIGN(iommu_pages * sizeof(u64), PAGE_SIZE) / PAGE_SIZE; }

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Benjamin Herrenschmidt2284.62%133.33%
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static unsigned long kvmppc_stt_pages(unsigned long tce_pages) { unsigned long stt_bytes = sizeof(struct kvmppc_spapr_tce_table) + (tce_pages * sizeof(struct page *)); return tce_pages + ALIGN(stt_bytes, PAGE_SIZE) / PAGE_SIZE; }

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Alexey Kardashevskiy44100.00%1100.00%
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static long kvmppc_account_memlimit(unsigned long stt_pages, bool inc) { long ret = 0; if (!current || !current->mm) return ret; /* process exited */ down_write(&current->mm->mmap_sem); if (inc) { unsigned long locked, lock_limit; locked = current->mm->locked_vm + stt_pages; lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; if (locked > lock_limit && !capable(CAP_IPC_LOCK)) ret = -ENOMEM; else current->mm->locked_vm += stt_pages; } else { if (WARN_ON_ONCE(stt_pages > current->mm->locked_vm)) stt_pages = current->mm->locked_vm; current->mm->locked_vm -= stt_pages; } pr_debug("[%d] RLIMIT_MEMLOCK KVM %c%ld %ld/%ld%s\n", current->pid, inc ? '+' : '-', stt_pages << PAGE_SHIFT, current->mm->locked_vm << PAGE_SHIFT, rlimit(RLIMIT_MEMLOCK), ret ? " - exceeded" : ""); up_write(&current->mm->mmap_sem); return ret; }

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static void kvm_spapr_tce_iommu_table_free(struct rcu_head *head) { struct kvmppc_spapr_tce_iommu_table *stit = container_of(head, struct kvmppc_spapr_tce_iommu_table, rcu); iommu_tce_table_put(stit->tbl); kfree(stit); }

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Alexey Kardashevskiy1950.00%266.67%
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Total38100.00%3100.00%


static void kvm_spapr_tce_liobn_put(struct kref *kref) { struct kvmppc_spapr_tce_iommu_table *stit = container_of(kref, struct kvmppc_spapr_tce_iommu_table, kref); list_del_rcu(&stit->next); call_rcu(&stit->rcu, kvm_spapr_tce_iommu_table_free); }

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Alexey Kardashevskiy2659.09%150.00%
Benjamin Herrenschmidt1840.91%150.00%
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extern void kvm_spapr_tce_release_iommu_group(struct kvm *kvm, struct iommu_group *grp) { int i; struct kvmppc_spapr_tce_table *stt; struct kvmppc_spapr_tce_iommu_table *stit, *tmp; struct iommu_table_group *table_group = NULL; list_for_each_entry_rcu(stt, &kvm->arch.spapr_tce_tables, list) { table_group = iommu_group_get_iommudata(grp); if (WARN_ON(!table_group)) continue; list_for_each_entry_safe(stit, tmp, &stt->iommu_tables, next) { for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) { if (table_group->tables[i] != stit->tbl) continue; kref_put(&stit->kref, kvm_spapr_tce_liobn_put); return; } } } }

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Alexey Kardashevskiy9682.05%375.00%
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extern long kvm_spapr_tce_attach_iommu_group(struct kvm *kvm, int tablefd, struct iommu_group *grp) { struct kvmppc_spapr_tce_table *stt = NULL; bool found = false; struct iommu_table *tbl = NULL; struct iommu_table_group *table_group; long i; struct kvmppc_spapr_tce_iommu_table *stit; struct fd f; f = fdget(tablefd); if (!f.file) return -EBADF; list_for_each_entry_rcu(stt, &kvm->arch.spapr_tce_tables, list) { if (stt == f.file->private_data) { found = true; break; } } fdput(f); if (!found) return -EINVAL; table_group = iommu_group_get_iommudata(grp); if (WARN_ON(!table_group)) return -EFAULT; for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) { struct iommu_table *tbltmp = table_group->tables[i]; if (!tbltmp) continue; /* * Make sure hardware table parameters are exactly the same; * this is used in the TCE handlers where boundary checks * use only the first attached table. */ if ((tbltmp->it_page_shift == stt->page_shift) && (tbltmp->it_offset == stt->offset) && (tbltmp->it_size == stt->size)) { /* * Reference the table to avoid races with * add/remove DMA windows. */ tbl = iommu_tce_table_get(tbltmp); break; } } if (!tbl) return -EINVAL; list_for_each_entry_rcu(stit, &stt->iommu_tables, next) { if (tbl != stit->tbl) continue; if (!kref_get_unless_zero(&stit->kref)) { /* stit is being destroyed */ iommu_tce_table_put(tbl); return -ENOTTY; } /* * The table is already known to this KVM, we just increased * its KVM reference counter and can return. */ return 0; } stit = kzalloc(sizeof(*stit), GFP_KERNEL); if (!stit) { iommu_tce_table_put(tbl); return -ENOMEM; } stit->tbl = tbl; kref_init(&stit->kref); list_add_rcu(&stit->next, &stt->iommu_tables); return 0; }

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Alexey Kardashevskiy23672.84%466.67%
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Wei Yongjun10.31%116.67%
Total324100.00%6100.00%


static void release_spapr_tce_table(struct rcu_head *head) { struct kvmppc_spapr_tce_table *stt = container_of(head, struct kvmppc_spapr_tce_table, rcu); unsigned long i, npages = kvmppc_tce_pages(stt->size); for (i = 0; i < npages; i++) __free_page(stt->pages[i]); kfree(stt); }

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Benjamin Herrenschmidt3450.75%150.00%
Alexey Kardashevskiy3349.25%150.00%
Total67100.00%2100.00%


static int kvm_spapr_tce_fault(struct vm_fault *vmf) { struct kvmppc_spapr_tce_table *stt = vmf->vma->vm_file->private_data; struct page *page; if (vmf->pgoff >= kvmppc_tce_pages(stt->size)) return VM_FAULT_SIGBUS; page = stt->pages[vmf->pgoff]; get_page(page); vmf->page = page; return 0; }

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Alexey Kardashevskiy6795.71%150.00%
Benjamin Herrenschmidt34.29%150.00%
Total70100.00%2100.00%

static const struct vm_operations_struct kvm_spapr_tce_vm_ops = { .fault = kvm_spapr_tce_fault, };
static int kvm_spapr_tce_mmap(struct file *file, struct vm_area_struct *vma) { vma->vm_ops = &kvm_spapr_tce_vm_ops; return 0; }

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static int kvm_spapr_tce_release(struct inode *inode, struct file *filp) { struct kvmppc_spapr_tce_table *stt = filp->private_data; struct kvmppc_spapr_tce_iommu_table *stit, *tmp; struct kvm *kvm = stt->kvm; mutex_lock(&kvm->lock); list_del_rcu(&stt->list); mutex_unlock(&kvm->lock); list_for_each_entry_safe(stit, tmp, &stt->iommu_tables, next) { WARN_ON(!kref_read(&stit->kref)); while (1) { if (kref_put(&stit->kref, kvm_spapr_tce_liobn_put)) break; } } kvm_put_kvm(stt->kvm); kvmppc_account_memlimit( kvmppc_stt_pages(kvmppc_tce_pages(stt->size)), false); call_rcu(&stt->rcu, release_spapr_tce_table); return 0; }

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Alexey Kardashevskiy11982.64%150.00%
Paul Mackerras2517.36%150.00%
Total144100.00%2100.00%

static const struct file_operations kvm_spapr_tce_fops = { .mmap = kvm_spapr_tce_mmap, .release = kvm_spapr_tce_release, };
long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm, struct kvm_create_spapr_tce_64 *args) { struct kvmppc_spapr_tce_table *stt = NULL; struct kvmppc_spapr_tce_table *siter; unsigned long npages, size; int ret = -ENOMEM; int i; if (!args->size) return -EINVAL; size = _ALIGN_UP(args->size, PAGE_SIZE >> 3); npages = kvmppc_tce_pages(size); ret = kvmppc_account_memlimit(kvmppc_stt_pages(npages), true); if (ret) return ret; ret = -ENOMEM; stt = kzalloc(sizeof(*stt) + npages * sizeof(struct page *), GFP_KERNEL); if (!stt) goto fail_acct; stt->liobn = args->liobn; stt->page_shift = args->page_shift; stt->offset = args->offset; stt->size = size; stt->kvm = kvm; INIT_LIST_HEAD_RCU(&stt->iommu_tables); for (i = 0; i < npages; i++) { stt->pages[i] = alloc_page(GFP_KERNEL | __GFP_ZERO); if (!stt->pages[i]) goto fail; } mutex_lock(&kvm->lock); /* Check this LIOBN hasn't been previously allocated */ ret = 0; list_for_each_entry(siter, &kvm->arch.spapr_tce_tables, list) { if (siter->liobn == args->liobn) { ret = -EBUSY; break; } } if (!ret) ret = anon_inode_getfd("kvm-spapr-tce", &kvm_spapr_tce_fops, stt, O_RDWR | O_CLOEXEC); if (ret >= 0) { list_add_rcu(&stt->list, &kvm->arch.spapr_tce_tables); kvm_get_kvm(kvm); } mutex_unlock(&kvm->lock); if (ret >= 0) return ret; fail: for (i = 0; i < npages; i++) if (stt->pages[i]) __free_page(stt->pages[i]); kfree(stt); fail_acct: kvmppc_account_memlimit(kvmppc_stt_pages(npages), false); return ret; }

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Alexey Kardashevskiy27874.33%133.33%
Paul Mackerras9625.67%266.67%
Total374100.00%3100.00%


static void kvmppc_clear_tce(struct iommu_table *tbl, unsigned long entry) { unsigned long hpa = 0; enum dma_data_direction dir = DMA_NONE; iommu_tce_xchg(tbl, entry, &hpa, &dir); }

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Alexey Kardashevskiy40100.00%1100.00%
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static long kvmppc_tce_iommu_mapped_dec(struct kvm *kvm, struct iommu_table *tbl, unsigned long entry) { struct mm_iommu_table_group_mem_t *mem = NULL; const unsigned long pgsize = 1ULL << tbl->it_page_shift; unsigned long *pua = IOMMU_TABLE_USERSPACE_ENTRY(tbl, entry); if (!pua) /* it_userspace allocation might be delayed */ return H_TOO_HARD; mem = mm_iommu_lookup(kvm->mm, *pua, pgsize); if (!mem) return H_TOO_HARD; mm_iommu_mapped_dec(mem); *pua = 0; return H_SUCCESS; }

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Alexey Kardashevskiy94100.00%1100.00%
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static long kvmppc_tce_iommu_unmap(struct kvm *kvm, struct iommu_table *tbl, unsigned long entry) { enum dma_data_direction dir = DMA_NONE; unsigned long hpa = 0; long ret; if (WARN_ON_ONCE(iommu_tce_xchg(tbl, entry, &hpa, &dir))) return H_HARDWARE; if (dir == DMA_NONE) return H_SUCCESS; ret = kvmppc_tce_iommu_mapped_dec(kvm, tbl, entry); if (ret != H_SUCCESS) iommu_tce_xchg(tbl, entry, &hpa, &dir); return ret; }

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Alexey Kardashevskiy98100.00%1100.00%
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long kvmppc_tce_iommu_map(struct kvm *kvm, struct iommu_table *tbl, unsigned long entry, unsigned long ua, enum dma_data_direction dir) { long ret; unsigned long hpa, *pua = IOMMU_TABLE_USERSPACE_ENTRY(tbl, entry); struct mm_iommu_table_group_mem_t *mem; if (!pua) /* it_userspace allocation might be delayed */ return H_TOO_HARD; mem = mm_iommu_lookup(kvm->mm, ua, 1ULL << tbl->it_page_shift); if (!mem) /* This only handles v2 IOMMU type, v1 is handled via ioctl() */ return H_TOO_HARD; if (WARN_ON_ONCE(mm_iommu_ua_to_hpa(mem, ua, &hpa))) return H_HARDWARE; if (mm_iommu_mapped_inc(mem)) return H_CLOSED; ret = iommu_tce_xchg(tbl, entry, &hpa, &dir); if (WARN_ON_ONCE(ret)) { mm_iommu_mapped_dec(mem); return H_HARDWARE; } if (dir != DMA_NONE) kvmppc_tce_iommu_mapped_dec(kvm, tbl, entry); *pua = ua; return 0; }

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Alexey Kardashevskiy167100.00%1100.00%
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long kvmppc_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn, unsigned long ioba, unsigned long tce) { struct kvmppc_spapr_tce_table *stt; long ret, idx; struct kvmppc_spapr_tce_iommu_table *stit; unsigned long entry, ua = 0; enum dma_data_direction dir; /* udbg_printf("H_PUT_TCE(): liobn=0x%lx ioba=0x%lx, tce=0x%lx\n", */ /* liobn, ioba, tce); */ stt = kvmppc_find_table(vcpu->kvm, liobn); if (!stt) return H_TOO_HARD; ret = kvmppc_ioba_validate(stt, ioba, 1); if (ret != H_SUCCESS) return ret; ret = kvmppc_tce_validate(stt, tce); if (ret != H_SUCCESS) return ret; dir = iommu_tce_direction(tce); idx = srcu_read_lock(&vcpu->kvm->srcu); if ((dir != DMA_NONE) && kvmppc_gpa_to_ua(vcpu->kvm, tce & ~(TCE_PCI_READ | TCE_PCI_WRITE), &ua, NULL)) { ret = H_PARAMETER; goto unlock_exit; } entry = ioba >> stt->page_shift; list_for_each_entry_lockless(stit, &stt->iommu_tables, next) { if (dir == DMA_NONE) ret = kvmppc_tce_iommu_unmap(vcpu->kvm, stit->tbl, entry); else ret = kvmppc_tce_iommu_map(vcpu->kvm, stit->tbl, entry, ua, dir); if (ret == H_SUCCESS) continue; if (ret == H_TOO_HARD) goto unlock_exit; WARN_ON_ONCE(1); kvmppc_clear_tce(stit->tbl, entry); } kvmppc_tce_put(stt, entry, tce); unlock_exit: srcu_read_unlock(&vcpu->kvm->srcu, idx); return ret; }

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Alexey Kardashevskiy280100.00%4100.00%
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EXPORT_SYMBOL_GPL(kvmppc_h_put_tce);
long kvmppc_h_put_tce_indirect(struct kvm_vcpu *vcpu, unsigned long liobn, unsigned long ioba, unsigned long tce_list, unsigned long npages) { struct kvmppc_spapr_tce_table *stt; long i, ret = H_SUCCESS, idx; unsigned long entry, ua = 0; u64 __user *tces; u64 tce; struct kvmppc_spapr_tce_iommu_table *stit; stt = kvmppc_find_table(vcpu->kvm, liobn); if (!stt) return H_TOO_HARD; entry = ioba >> stt->page_shift; /* * SPAPR spec says that the maximum size of the list is 512 TCEs * so the whole table fits in 4K page */ if (npages > 512) return H_PARAMETER; if (tce_list & (SZ_4K - 1)) return H_PARAMETER; ret = kvmppc_ioba_validate(stt, ioba, npages); if (ret != H_SUCCESS) return ret; idx = srcu_read_lock(&vcpu->kvm->srcu); if (kvmppc_gpa_to_ua(vcpu->kvm, tce_list, &ua, NULL)) { ret = H_TOO_HARD; goto unlock_exit; } tces = (u64 __user *) ua; for (i = 0; i < npages; ++i) { if (get_user(tce, tces + i)) { ret = H_TOO_HARD; goto unlock_exit; } tce = be64_to_cpu(tce); ret = kvmppc_tce_validate(stt, tce); if (ret != H_SUCCESS) goto unlock_exit; if (kvmppc_gpa_to_ua(vcpu->kvm, tce & ~(TCE_PCI_READ | TCE_PCI_WRITE), &ua, NULL)) return H_PARAMETER; list_for_each_entry_lockless(stit, &stt->iommu_tables, next) { ret = kvmppc_tce_iommu_map(vcpu->kvm, stit->tbl, entry + i, ua, iommu_tce_direction(tce)); if (ret == H_SUCCESS) continue; if (ret == H_TOO_HARD) goto unlock_exit; WARN_ON_ONCE(1); kvmppc_clear_tce(stit->tbl, entry); } kvmppc_tce_put(stt, entry + i, tce); } unlock_exit: srcu_read_unlock(&vcpu->kvm->srcu, idx); return ret; }

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Alexey Kardashevskiy35399.44%480.00%
Daniel Axtens20.56%120.00%
Total355100.00%5100.00%

EXPORT_SYMBOL_GPL(kvmppc_h_put_tce_indirect);
long kvmppc_h_stuff_tce(struct kvm_vcpu *vcpu, unsigned long liobn, unsigned long ioba, unsigned long tce_value, unsigned long npages) { struct kvmppc_spapr_tce_table *stt; long i, ret; struct kvmppc_spapr_tce_iommu_table *stit; stt = kvmppc_find_table(vcpu->kvm, liobn); if (!stt) return H_TOO_HARD; ret = kvmppc_ioba_validate(stt, ioba, npages); if (ret != H_SUCCESS) return ret; /* Check permission bits only to allow userspace poison TCE for debug */ if (tce_value & (TCE_PCI_WRITE | TCE_PCI_READ)) return H_PARAMETER; list_for_each_entry_lockless(stit, &stt->iommu_tables, next) { unsigned long entry = ioba >> stit->tbl->it_page_shift; for (i = 0; i < npages; ++i) { ret = kvmppc_tce_iommu_unmap(vcpu->kvm, stit->tbl, entry + i); if (ret == H_SUCCESS) continue; if (ret == H_TOO_HARD) return ret; WARN_ON_ONCE(1); kvmppc_clear_tce(stit->tbl, entry); } } for (i = 0; i < npages; ++i, ioba += (1ULL << stt->page_shift)) kvmppc_tce_put(stt, ioba >> stt->page_shift, tce_value); return H_SUCCESS; }

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Alexey Kardashevskiy217100.00%3100.00%
Total217100.00%3100.00%

EXPORT_SYMBOL_GPL(kvmppc_h_stuff_tce);

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Alexey Kardashevskiy244186.28%1058.82%
Benjamin Herrenschmidt2609.19%15.88%
Paul Mackerras1214.28%211.76%
Ingo Molnar30.11%15.88%
Daniel Axtens20.07%15.88%
Aneesh Kumar K.V10.04%15.88%
Wei Yongjun10.04%15.88%
Total2829100.00%17100.00%
Directory: arch/powerpc/kvm
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