--- /dev/null
+/*
+ * Copyright 2018 Red Hat Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+#include "nouveau_svm.h"
+#include "nouveau_drv.h"
+#include "nouveau_chan.h"
+
+#include <nvif/notify.h>
+#include <nvif/object.h>
+#include <nvif/vmm.h>
+
+#include <nvif/class.h>
+#include <nvif/clb069.h>
+#include <nvif/ifc00d.h>
+
+#include <linux/sched/mm.h>
+#include <linux/sort.h>
+#include <linux/hmm.h>
+
+struct nouveau_svm {
+ struct nouveau_drm *drm;
+ struct mutex mutex;
+ struct list_head inst;
+
+ struct nouveau_svm_fault_buffer {
+ int id;
+ struct nvif_object object;
+ u32 entries;
+ u32 getaddr;
+ u32 putaddr;
+ u32 get;
+ u32 put;
+ struct nvif_notify notify;
+
+ struct nouveau_svm_fault {
+ u64 inst;
+ u64 addr;
+ u64 time;
+ u32 engine;
+ u8 gpc;
+ u8 hub;
+ u8 access;
+ u8 client;
+ u8 fault;
+ struct nouveau_svmm *svmm;
+ } **fault;
+ int fault_nr;
+ } buffer[1];
+};
+
+#define SVM_DBG(s,f,a...) NV_DEBUG((s)->drm, "svm: "f"\n", ##a)
+#define SVM_ERR(s,f,a...) NV_WARN((s)->drm, "svm: "f"\n", ##a)
+
+struct nouveau_ivmm {
+ struct nouveau_svmm *svmm;
+ u64 inst;
+ struct list_head head;
+};
+
+static struct nouveau_ivmm *
+nouveau_ivmm_find(struct nouveau_svm *svm, u64 inst)
+{
+ struct nouveau_ivmm *ivmm;
+ list_for_each_entry(ivmm, &svm->inst, head) {
+ if (ivmm->inst == inst)
+ return ivmm;
+ }
+ return NULL;
+}
+
+struct nouveau_svmm {
+ struct nouveau_vmm *vmm;
+ struct {
+ unsigned long start;
+ unsigned long limit;
+ } unmanaged;
+
+ struct mutex mutex;
+
+ struct mm_struct *mm;
+ struct hmm_mirror mirror;
+};
+
+#define SVMM_DBG(s,f,a...) \
+ NV_DEBUG((s)->vmm->cli->drm, "svm-%p: "f"\n", (s), ##a)
+#define SVMM_ERR(s,f,a...) \
+ NV_WARN((s)->vmm->cli->drm, "svm-%p: "f"\n", (s), ##a)
+
+/* Unlink channel instance from SVMM. */
+void
+nouveau_svmm_part(struct nouveau_svmm *svmm, u64 inst)
+{
+ struct nouveau_ivmm *ivmm;
+ if (svmm) {
+ mutex_lock(&svmm->vmm->cli->drm->svm->mutex);
+ ivmm = nouveau_ivmm_find(svmm->vmm->cli->drm->svm, inst);
+ if (ivmm) {
+ list_del(&ivmm->head);
+ kfree(ivmm);
+ }
+ mutex_unlock(&svmm->vmm->cli->drm->svm->mutex);
+ }
+}
+
+/* Link channel instance to SVMM. */
+int
+nouveau_svmm_join(struct nouveau_svmm *svmm, u64 inst)
+{
+ struct nouveau_ivmm *ivmm;
+ if (svmm) {
+ if (!(ivmm = kmalloc(sizeof(*ivmm), GFP_KERNEL)))
+ return -ENOMEM;
+ ivmm->svmm = svmm;
+ ivmm->inst = inst;
+
+ mutex_lock(&svmm->vmm->cli->drm->svm->mutex);
+ list_add(&ivmm->head, &svmm->vmm->cli->drm->svm->inst);
+ mutex_unlock(&svmm->vmm->cli->drm->svm->mutex);
+ }
+ return 0;
+}
+
+/* Invalidate SVMM address-range on GPU. */
+static void
+nouveau_svmm_invalidate(struct nouveau_svmm *svmm, u64 start, u64 limit)
+{
+ if (limit > start) {
+ bool super = svmm->vmm->vmm.object.client->super;
+ svmm->vmm->vmm.object.client->super = true;
+ nvif_object_mthd(&svmm->vmm->vmm.object, NVIF_VMM_V0_PFNCLR,
+ &(struct nvif_vmm_pfnclr_v0) {
+ .addr = start,
+ .size = limit - start,
+ }, sizeof(struct nvif_vmm_pfnclr_v0));
+ svmm->vmm->vmm.object.client->super = super;
+ }
+}
+
+static int
+nouveau_svmm_sync_cpu_device_pagetables(struct hmm_mirror *mirror,
+ const struct hmm_update *update)
+{
+ struct nouveau_svmm *svmm = container_of(mirror, typeof(*svmm), mirror);
+ unsigned long start = update->start;
+ unsigned long limit = update->end;
+
+ if (!update->blockable)
+ return -EAGAIN;
+
+ SVMM_DBG(svmm, "invalidate %016lx-%016lx", start, limit);
+
+ mutex_lock(&svmm->mutex);
+ if (limit > svmm->unmanaged.start && start < svmm->unmanaged.limit) {
+ if (start < svmm->unmanaged.start) {
+ nouveau_svmm_invalidate(svmm, start,
+ svmm->unmanaged.limit);
+ }
+ start = svmm->unmanaged.limit;
+ }
+
+ nouveau_svmm_invalidate(svmm, start, limit);
+ mutex_unlock(&svmm->mutex);
+ return 0;
+}
+
+static void
+nouveau_svmm_release(struct hmm_mirror *mirror)
+{
+}
+
+static const struct hmm_mirror_ops
+nouveau_svmm = {
+ .sync_cpu_device_pagetables = nouveau_svmm_sync_cpu_device_pagetables,
+ .release = nouveau_svmm_release,
+};
+
+void
+nouveau_svmm_fini(struct nouveau_svmm **psvmm)
+{
+ struct nouveau_svmm *svmm = *psvmm;
+ if (svmm) {
+ hmm_mirror_unregister(&svmm->mirror);
+ kfree(*psvmm);
+ *psvmm = NULL;
+ }
+}
+
+int
+nouveau_svmm_init(struct drm_device *dev, void *data,
+ struct drm_file *file_priv)
+{
+ struct nouveau_cli *cli = nouveau_cli(file_priv);
+ struct nouveau_svmm *svmm;
+ struct drm_nouveau_svm_init *args = data;
+ int ret;
+
+ /* Allocate tracking for SVM-enabled VMM. */
+ if (!(svmm = kzalloc(sizeof(*svmm), GFP_KERNEL)))
+ return -ENOMEM;
+ svmm->vmm = &cli->svm;
+ svmm->unmanaged.start = args->unmanaged_addr;
+ svmm->unmanaged.limit = args->unmanaged_addr + args->unmanaged_size;
+ mutex_init(&svmm->mutex);
+
+ /* Check that SVM isn't already enabled for the client. */
+ mutex_lock(&cli->mutex);
+ if (cli->svm.cli) {
+ ret = -EBUSY;
+ goto done;
+ }
+
+ /* Allocate a new GPU VMM that can support SVM (managed by the
+ * client, with replayable faults enabled).
+ *
+ * All future channel/memory allocations will make use of this
+ * VMM instead of the standard one.
+ */
+ ret = nvif_vmm_init(&cli->mmu, cli->vmm.vmm.object.oclass, true,
+ args->unmanaged_addr, args->unmanaged_size,
+ &(struct gp100_vmm_v0) {
+ .fault_replay = true,
+ }, sizeof(struct gp100_vmm_v0), &cli->svm.vmm);
+ if (ret)
+ goto done;
+
+ /* Enable HMM mirroring of CPU address-space to VMM. */
+ svmm->mm = get_task_mm(current);
+ down_write(&svmm->mm->mmap_sem);
+ svmm->mirror.ops = &nouveau_svmm;
+ ret = hmm_mirror_register(&svmm->mirror, svmm->mm);
+ if (ret == 0) {
+ cli->svm.svmm = svmm;
+ cli->svm.cli = cli;
+ }
+ up_write(&svmm->mm->mmap_sem);
+ mmput(svmm->mm);
+
+done:
+ if (ret)
+ nouveau_svmm_fini(&svmm);
+ mutex_unlock(&cli->mutex);
+ return ret;
+}
+
+static const u64
+nouveau_svm_pfn_flags[HMM_PFN_FLAG_MAX] = {
+ [HMM_PFN_VALID ] = NVIF_VMM_PFNMAP_V0_V,
+ [HMM_PFN_WRITE ] = NVIF_VMM_PFNMAP_V0_W,
+ [HMM_PFN_DEVICE_PRIVATE] = NVIF_VMM_PFNMAP_V0_VRAM,
+};
+
+static const u64
+nouveau_svm_pfn_values[HMM_PFN_VALUE_MAX] = {
+ [HMM_PFN_ERROR ] = ~NVIF_VMM_PFNMAP_V0_V,
+ [HMM_PFN_NONE ] = NVIF_VMM_PFNMAP_V0_NONE,
+ [HMM_PFN_SPECIAL] = ~NVIF_VMM_PFNMAP_V0_V,
+};
+
+/* Issue fault replay for GPU to retry accesses that faulted previously. */
+static void
+nouveau_svm_fault_replay(struct nouveau_svm *svm)
+{
+ SVM_DBG(svm, "replay");
+ WARN_ON(nvif_object_mthd(&svm->drm->client.vmm.vmm.object,
+ GP100_VMM_VN_FAULT_REPLAY,
+ &(struct gp100_vmm_fault_replay_vn) {},
+ sizeof(struct gp100_vmm_fault_replay_vn)));
+}
+
+/* Cancel a replayable fault that could not be handled.
+ *
+ * Cancelling the fault will trigger recovery to reset the engine
+ * and kill the offending channel (ie. GPU SIGSEGV).
+ */
+static void
+nouveau_svm_fault_cancel(struct nouveau_svm *svm,
+ u64 inst, u8 hub, u8 gpc, u8 client)
+{
+ SVM_DBG(svm, "cancel %016llx %d %02x %02x", inst, hub, gpc, client);
+ WARN_ON(nvif_object_mthd(&svm->drm->client.vmm.vmm.object,
+ GP100_VMM_VN_FAULT_CANCEL,
+ &(struct gp100_vmm_fault_cancel_v0) {
+ .hub = hub,
+ .gpc = gpc,
+ .client = client,
+ .inst = inst,
+ }, sizeof(struct gp100_vmm_fault_cancel_v0)));
+}
+
+static void
+nouveau_svm_fault_cancel_fault(struct nouveau_svm *svm,
+ struct nouveau_svm_fault *fault)
+{
+ nouveau_svm_fault_cancel(svm, fault->inst,
+ fault->hub,
+ fault->gpc,
+ fault->client);
+}
+
+static int
+nouveau_svm_fault_cmp(const void *a, const void *b)
+{
+ const struct nouveau_svm_fault *fa = *(struct nouveau_svm_fault **)a;
+ const struct nouveau_svm_fault *fb = *(struct nouveau_svm_fault **)b;
+ int ret;
+ if ((ret = (s64)fa->inst - fb->inst))
+ return ret;
+ if ((ret = (s64)fa->addr - fb->addr))
+ return ret;
+ /*XXX: atomic? */
+ return (fa->access == 0 || fa->access == 3) -
+ (fb->access == 0 || fb->access == 3);
+}
+
+static void
+nouveau_svm_fault_cache(struct nouveau_svm *svm,
+ struct nouveau_svm_fault_buffer *buffer, u32 offset)
+{
+ struct nvif_object *memory = &buffer->object;
+ const u32 instlo = nvif_rd32(memory, offset + 0x00);
+ const u32 insthi = nvif_rd32(memory, offset + 0x04);
+ const u32 addrlo = nvif_rd32(memory, offset + 0x08);
+ const u32 addrhi = nvif_rd32(memory, offset + 0x0c);
+ const u32 timelo = nvif_rd32(memory, offset + 0x10);
+ const u32 timehi = nvif_rd32(memory, offset + 0x14);
+ const u32 engine = nvif_rd32(memory, offset + 0x18);
+ const u32 info = nvif_rd32(memory, offset + 0x1c);
+ const u64 inst = (u64)insthi << 32 | instlo;
+ const u8 gpc = (info & 0x1f000000) >> 24;
+ const u8 hub = (info & 0x00100000) >> 20;
+ const u8 client = (info & 0x00007f00) >> 8;
+ struct nouveau_svm_fault *fault;
+
+ //XXX: i think we're supposed to spin waiting */
+ if (WARN_ON(!(info & 0x80000000)))
+ return;
+
+ nvif_mask(memory, offset + 0x1c, 0x80000000, 0x00000000);
+
+ if (!buffer->fault[buffer->fault_nr]) {
+ fault = kmalloc(sizeof(*fault), GFP_KERNEL);
+ if (WARN_ON(!fault)) {
+ nouveau_svm_fault_cancel(svm, inst, hub, gpc, client);
+ return;
+ }
+ buffer->fault[buffer->fault_nr] = fault;
+ }
+
+ fault = buffer->fault[buffer->fault_nr++];
+ fault->inst = inst;
+ fault->addr = (u64)addrhi << 32 | addrlo;
+ fault->time = (u64)timehi << 32 | timelo;
+ fault->engine = engine;
+ fault->gpc = gpc;
+ fault->hub = hub;
+ fault->access = (info & 0x000f0000) >> 16;
+ fault->client = client;
+ fault->fault = (info & 0x0000001f);
+
+ SVM_DBG(svm, "fault %016llx %016llx %02x",
+ fault->inst, fault->addr, fault->access);
+}
+
+static int
+nouveau_svm_fault(struct nvif_notify *notify)
+{
+ struct nouveau_svm_fault_buffer *buffer =
+ container_of(notify, typeof(*buffer), notify);
+ struct nouveau_svm *svm =
+ container_of(buffer, typeof(*svm), buffer[buffer->id]);
+ struct nvif_object *device = &svm->drm->client.device.object;
+ struct nouveau_svmm *svmm;
+ struct {
+ struct {
+ struct nvif_ioctl_v0 i;
+ struct nvif_ioctl_mthd_v0 m;
+ struct nvif_vmm_pfnmap_v0 p;
+ } i;
+ u64 phys[16];
+ } args;
+ struct hmm_range range;
+ struct vm_area_struct *vma;
+ u64 inst, start, limit;
+ int fi, fn, pi, fill;
+ int replay = 0, ret;
+
+ /* Parse available fault buffer entries into a cache, and update
+ * the GET pointer so HW can reuse the entries.
+ */
+ SVM_DBG(svm, "fault handler");
+ if (buffer->get == buffer->put) {
+ buffer->put = nvif_rd32(device, buffer->putaddr);
+ buffer->get = nvif_rd32(device, buffer->getaddr);
+ if (buffer->get == buffer->put)
+ return NVIF_NOTIFY_KEEP;
+ }
+ buffer->fault_nr = 0;
+
+ SVM_DBG(svm, "get %08x put %08x", buffer->get, buffer->put);
+ while (buffer->get != buffer->put) {
+ nouveau_svm_fault_cache(svm, buffer, buffer->get * 0x20);
+ if (++buffer->get == buffer->entries)
+ buffer->get = 0;
+ }
+ nvif_wr32(device, buffer->getaddr, buffer->get);
+ SVM_DBG(svm, "%d fault(s) pending", buffer->fault_nr);
+
+ /* Sort parsed faults by instance pointer to prevent unnecessary
+ * instance to SVMM translations, followed by address and access
+ * type to reduce the amount of work when handling the faults.
+ */
+ sort(buffer->fault, buffer->fault_nr, sizeof(*buffer->fault),
+ nouveau_svm_fault_cmp, NULL);
+
+ /* Lookup SVMM structure for each unique instance pointer. */
+ mutex_lock(&svm->mutex);
+ for (fi = 0, svmm = NULL; fi < buffer->fault_nr; fi++) {
+ if (!svmm || buffer->fault[fi]->inst != inst) {
+ struct nouveau_ivmm *ivmm =
+ nouveau_ivmm_find(svm, buffer->fault[fi]->inst);
+ svmm = ivmm ? ivmm->svmm : NULL;
+ inst = buffer->fault[fi]->inst;
+ SVM_DBG(svm, "inst %016llx -> svm-%p", inst, svmm);
+ }
+ buffer->fault[fi]->svmm = svmm;
+ }
+ mutex_unlock(&svm->mutex);
+
+ /* Process list of faults. */
+ args.i.i.version = 0;
+ args.i.i.type = NVIF_IOCTL_V0_MTHD;
+ args.i.m.version = 0;
+ args.i.m.method = NVIF_VMM_V0_PFNMAP;
+ args.i.p.version = 0;
+
+ for (fi = 0; fn = fi + 1, fi < buffer->fault_nr; fi = fn) {
+ /* Cancel any faults from non-SVM channels. */
+ if (!(svmm = buffer->fault[fi]->svmm)) {
+ nouveau_svm_fault_cancel_fault(svm, buffer->fault[fi]);
+ continue;
+ }
+ SVMM_DBG(svmm, "addr %016llx", buffer->fault[fi]->addr);
+
+ /* We try and group handling of faults within a small
+ * window into a single update.
+ */
+ start = buffer->fault[fi]->addr;
+ limit = start + (ARRAY_SIZE(args.phys) << PAGE_SHIFT);
+ if (start < svmm->unmanaged.limit)
+ limit = min_t(u64, limit, svmm->unmanaged.start);
+ else
+ if (limit > svmm->unmanaged.start)
+ start = max_t(u64, start, svmm->unmanaged.limit);
+ SVMM_DBG(svmm, "wndw %016llx-%016llx", start, limit);
+
+ /* Intersect fault window with the CPU VMA, cancelling
+ * the fault if the address is invalid.
+ */
+ down_read(&svmm->mm->mmap_sem);
+ vma = find_vma_intersection(svmm->mm, start, limit);
+ if (!vma) {
+ SVMM_ERR(svmm, "wndw %016llx-%016llx", start, limit);
+ up_read(&svmm->mm->mmap_sem);
+ nouveau_svm_fault_cancel_fault(svm, buffer->fault[fi]);
+ continue;
+ }
+ start = max_t(u64, start, vma->vm_start);
+ limit = min_t(u64, limit, vma->vm_end);
+ SVMM_DBG(svmm, "wndw %016llx-%016llx", start, limit);
+
+ if (buffer->fault[fi]->addr != start) {
+ SVMM_ERR(svmm, "addr %016llx", buffer->fault[fi]->addr);
+ up_read(&svmm->mm->mmap_sem);
+ nouveau_svm_fault_cancel_fault(svm, buffer->fault[fi]);
+ continue;
+ }
+
+ /* Prepare the GPU-side update of all pages within the
+ * fault window, determining required pages and access
+ * permissions based on pending faults.
+ */
+ args.i.p.page = PAGE_SHIFT;
+ args.i.p.addr = start;
+ for (fn = fi, pi = 0;;) {
+ /* Determine required permissions based on GPU fault
+ * access flags.
+ *XXX: atomic?
+ */
+ if (buffer->fault[fn]->access != 0 /* READ. */ &&
+ buffer->fault[fn]->access != 3 /* PREFETCH. */) {
+ args.phys[pi++] = NVIF_VMM_PFNMAP_V0_V |
+ NVIF_VMM_PFNMAP_V0_W;
+ } else {
+ args.phys[pi++] = NVIF_VMM_PFNMAP_V0_V;
+ }
+ args.i.p.size = pi << PAGE_SHIFT;
+
+ /* It's okay to skip over duplicate addresses from the
+ * same SVMM as faults are ordered by access type such
+ * that only the first one needs to be handled.
+ *
+ * ie. WRITE faults appear first, thus any handling of
+ * pending READ faults will already be satisfied.
+ */
+ while (++fn < buffer->fault_nr &&
+ buffer->fault[fn]->svmm == svmm &&
+ buffer->fault[fn ]->addr ==
+ buffer->fault[fn - 1]->addr);
+
+ /* If the next fault is outside the window, or all GPU
+ * faults have been dealt with, we're done here.
+ */
+ if (fn >= buffer->fault_nr ||
+ buffer->fault[fn]->svmm != svmm ||
+ buffer->fault[fn]->addr >= limit)
+ break;
+
+ /* Fill in the gap between this fault and the next. */
+ fill = (buffer->fault[fn ]->addr -
+ buffer->fault[fn - 1]->addr) >> PAGE_SHIFT;
+ while (--fill)
+ args.phys[pi++] = NVIF_VMM_PFNMAP_V0_NONE;
+ }
+
+ SVMM_DBG(svmm, "wndw %016llx-%016llx covering %d fault(s)",
+ args.i.p.addr,
+ args.i.p.addr + args.i.p.size, fn - fi);
+
+ /* Have HMM fault pages within the fault window to the GPU. */
+ range.vma = vma;
+ range.start = args.i.p.addr;
+ range.end = args.i.p.addr + args.i.p.size;
+ range.pfns = args.phys;
+ range.flags = nouveau_svm_pfn_flags;
+ range.values = nouveau_svm_pfn_values;
+ range.pfn_shift = NVIF_VMM_PFNMAP_V0_ADDR_SHIFT;
+again:
+ ret = hmm_vma_fault(&range, true);
+ if (ret == 0) {
+ mutex_lock(&svmm->mutex);
+ if (!hmm_vma_range_done(&range)) {
+ mutex_unlock(&svmm->mutex);
+ goto again;
+ }
+
+ svmm->vmm->vmm.object.client->super = true;
+ ret = nvif_object_ioctl(&svmm->vmm->vmm.object,
+ &args, sizeof(args.i) +
+ pi * sizeof(args.phys[0]),
+ NULL);
+ svmm->vmm->vmm.object.client->super = false;
+ mutex_unlock(&svmm->mutex);
+ }
+ up_read(&svmm->mm->mmap_sem);
+
+ /* Cancel any faults in the window whose pages didn't manage
+ * to keep their valid bit, or stay writeable when required.
+ *
+ * If handling failed completely, cancel all faults.
+ */
+ while (fi < fn) {
+ struct nouveau_svm_fault *fault = buffer->fault[fi++];
+ pi = (fault->addr - range.start) >> PAGE_SHIFT;
+ if (ret ||
+ !(range.pfns[pi] & NVIF_VMM_PFNMAP_V0_V) ||
+ (!(range.pfns[pi] & NVIF_VMM_PFNMAP_V0_W) &&
+ fault->access != 0 && fault->access != 3)) {
+ nouveau_svm_fault_cancel_fault(svm, fault);
+ continue;
+ }
+ replay++;
+ }
+ }
+
+ /* Issue fault replay to the GPU. */
+ if (replay)
+ nouveau_svm_fault_replay(svm);
+ return NVIF_NOTIFY_KEEP;
+}
+
+static void
+nouveau_svm_fault_buffer_fini(struct nouveau_svm *svm, int id)
+{
+ struct nouveau_svm_fault_buffer *buffer = &svm->buffer[id];
+ nvif_notify_put(&buffer->notify);
+}
+
+static int
+nouveau_svm_fault_buffer_init(struct nouveau_svm *svm, int id)
+{
+ struct nouveau_svm_fault_buffer *buffer = &svm->buffer[id];
+ struct nvif_object *device = &svm->drm->client.device.object;
+ buffer->get = nvif_rd32(device, buffer->getaddr);
+ buffer->put = nvif_rd32(device, buffer->putaddr);
+ SVM_DBG(svm, "get %08x put %08x (init)", buffer->get, buffer->put);
+ return nvif_notify_get(&buffer->notify);
+}
+
+static void
+nouveau_svm_fault_buffer_dtor(struct nouveau_svm *svm, int id)
+{
+ struct nouveau_svm_fault_buffer *buffer = &svm->buffer[id];
+ int i;
+
+ if (buffer->fault) {
+ for (i = 0; buffer->fault[i] && i < buffer->entries; i++)
+ kfree(buffer->fault[i]);
+ kvfree(buffer->fault);
+ }
+
+ nouveau_svm_fault_buffer_fini(svm, id);
+
+ nvif_notify_fini(&buffer->notify);
+ nvif_object_fini(&buffer->object);
+}
+
+static int
+nouveau_svm_fault_buffer_ctor(struct nouveau_svm *svm, s32 oclass, int id)
+{
+ struct nouveau_svm_fault_buffer *buffer = &svm->buffer[id];
+ struct nouveau_drm *drm = svm->drm;
+ struct nvif_object *device = &drm->client.device.object;
+ struct nvif_clb069_v0 args = {};
+ int ret;
+
+ buffer->id = id;
+
+ ret = nvif_object_init(device, 0, oclass, &args, sizeof(args),
+ &buffer->object);
+ if (ret < 0) {
+ SVM_ERR(svm, "Fault buffer allocation failed: %d", ret);
+ return ret;
+ }
+
+ nvif_object_map(&buffer->object, NULL, 0);
+ buffer->entries = args.entries;
+ buffer->getaddr = args.get;
+ buffer->putaddr = args.put;
+
+ ret = nvif_notify_init(&buffer->object, nouveau_svm_fault, true,
+ NVB069_V0_NTFY_FAULT, NULL, 0, 0,
+ &buffer->notify);
+ if (ret)
+ return ret;
+
+ buffer->fault = kvzalloc(sizeof(*buffer->fault) * buffer->entries, GFP_KERNEL);
+ if (!buffer->fault)
+ return -ENOMEM;
+
+ return nouveau_svm_fault_buffer_init(svm, id);
+}
+
+void
+nouveau_svm_resume(struct nouveau_drm *drm)
+{
+ struct nouveau_svm *svm = drm->svm;
+ if (svm)
+ nouveau_svm_fault_buffer_init(svm, 0);
+}
+
+void
+nouveau_svm_suspend(struct nouveau_drm *drm)
+{
+ struct nouveau_svm *svm = drm->svm;
+ if (svm)
+ nouveau_svm_fault_buffer_fini(svm, 0);
+}
+
+void
+nouveau_svm_fini(struct nouveau_drm *drm)
+{
+ struct nouveau_svm *svm = drm->svm;
+ if (svm) {
+ nouveau_svm_fault_buffer_dtor(svm, 0);
+ kfree(drm->svm);
+ drm->svm = NULL;
+ }
+}
+
+void
+nouveau_svm_init(struct nouveau_drm *drm)
+{
+ static const struct nvif_mclass buffers[] = {
+ { VOLTA_FAULT_BUFFER_A, 0 },
+ { MAXWELL_FAULT_BUFFER_A, 0 },
+ {}
+ };
+ struct nouveau_svm *svm;
+ int ret;
+
+ /* Disable on Volta and newer until channel recovery is fixed,
+ * otherwise clients will have a trivial way to trash the GPU
+ * for everyone.
+ */
+ if (drm->client.device.info.family > NV_DEVICE_INFO_V0_PASCAL)
+ return;
+
+ if (!(drm->svm = svm = kzalloc(sizeof(*drm->svm), GFP_KERNEL)))
+ return;
+
+ drm->svm->drm = drm;
+ mutex_init(&drm->svm->mutex);
+ INIT_LIST_HEAD(&drm->svm->inst);
+
+ ret = nvif_mclass(&drm->client.device.object, buffers);
+ if (ret < 0) {
+ SVM_DBG(svm, "No supported fault buffer class");
+ nouveau_svm_fini(drm);
+ return;
+ }
+
+ ret = nouveau_svm_fault_buffer_ctor(svm, buffers[ret].oclass, 0);
+ if (ret) {
+ nouveau_svm_fini(drm);
+ return;
+ }
+
+ SVM_DBG(svm, "Initialised");
+}