xref: /openbmc/qemu/hw/ppc/spapr_nvdimm.c (revision d2dfe0b5)
1 /*
2  * QEMU PAPR Storage Class Memory Interfaces
3  *
4  * Copyright (c) 2019-2020, IBM Corporation.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 #include "qemu/osdep.h"
25 #include "qemu/cutils.h"
26 #include "qapi/error.h"
27 #include "hw/ppc/spapr_drc.h"
28 #include "hw/ppc/spapr_nvdimm.h"
29 #include "hw/mem/nvdimm.h"
30 #include "qemu/nvdimm-utils.h"
31 #include "hw/ppc/fdt.h"
32 #include "qemu/range.h"
33 #include "hw/ppc/spapr_numa.h"
34 #include "block/thread-pool.h"
35 #include "migration/vmstate.h"
36 #include "qemu/pmem.h"
37 #include "hw/qdev-properties.h"
38 
39 /* DIMM health bitmap bitmap indicators. Taken from kernel's papr_scm.c */
40 /* SCM device is unable to persist memory contents */
41 #define PAPR_PMEM_UNARMED PPC_BIT(0)
42 
43 /*
44  * The nvdimm size should be aligned to SCM block size.
45  * The SCM block size should be aligned to SPAPR_MEMORY_BLOCK_SIZE
46  * in order to have SCM regions not to overlap with dimm memory regions.
47  * The SCM devices can have variable block sizes. For now, fixing the
48  * block size to the minimum value.
49  */
50 #define SPAPR_MINIMUM_SCM_BLOCK_SIZE SPAPR_MEMORY_BLOCK_SIZE
51 
52 /* Have an explicit check for alignment */
53 QEMU_BUILD_BUG_ON(SPAPR_MINIMUM_SCM_BLOCK_SIZE % SPAPR_MEMORY_BLOCK_SIZE);
54 
55 #define TYPE_SPAPR_NVDIMM "spapr-nvdimm"
56 OBJECT_DECLARE_TYPE(SpaprNVDIMMDevice, SPAPRNVDIMMClass, SPAPR_NVDIMM)
57 
58 struct SPAPRNVDIMMClass {
59     /* private */
60     NVDIMMClass parent_class;
61 
62     /* public */
63     void (*realize)(NVDIMMDevice *dimm, Error **errp);
64     void (*unrealize)(NVDIMMDevice *dimm, Error **errp);
65 };
66 
67 bool spapr_nvdimm_validate(HotplugHandler *hotplug_dev, NVDIMMDevice *nvdimm,
68                            uint64_t size, Error **errp)
69 {
70     const MachineClass *mc = MACHINE_GET_CLASS(hotplug_dev);
71     const MachineState *ms = MACHINE(hotplug_dev);
72     PCDIMMDevice *dimm = PC_DIMM(nvdimm);
73     MemoryRegion *mr = host_memory_backend_get_memory(dimm->hostmem);
74     g_autofree char *uuidstr = NULL;
75     QemuUUID uuid;
76     int ret;
77 
78     if (!mc->nvdimm_supported) {
79         error_setg(errp, "NVDIMM hotplug not supported for this machine");
80         return false;
81     }
82 
83     if (!ms->nvdimms_state->is_enabled) {
84         error_setg(errp, "nvdimm device found but 'nvdimm=off' was set");
85         return false;
86     }
87 
88     if (object_property_get_int(OBJECT(nvdimm), NVDIMM_LABEL_SIZE_PROP,
89                                 &error_abort) == 0) {
90         error_setg(errp, "PAPR requires NVDIMM devices to have label-size set");
91         return false;
92     }
93 
94     if (size % SPAPR_MINIMUM_SCM_BLOCK_SIZE) {
95         error_setg(errp, "PAPR requires NVDIMM memory size (excluding label)"
96                    " to be a multiple of %" PRIu64 "MB",
97                    SPAPR_MINIMUM_SCM_BLOCK_SIZE / MiB);
98         return false;
99     }
100 
101     uuidstr = object_property_get_str(OBJECT(nvdimm), NVDIMM_UUID_PROP,
102                                       &error_abort);
103     ret = qemu_uuid_parse(uuidstr, &uuid);
104     g_assert(!ret);
105 
106     if (qemu_uuid_is_null(&uuid)) {
107         error_setg(errp, "NVDIMM device requires the uuid to be set");
108         return false;
109     }
110 
111     if (object_dynamic_cast(OBJECT(nvdimm), TYPE_SPAPR_NVDIMM) &&
112         (memory_region_get_fd(mr) < 0)) {
113         error_setg(errp, "spapr-nvdimm device requires the "
114                    "memdev %s to be of memory-backend-file type",
115                    object_get_canonical_path_component(OBJECT(dimm->hostmem)));
116         return false;
117     }
118 
119     return true;
120 }
121 
122 
123 void spapr_add_nvdimm(DeviceState *dev, uint64_t slot)
124 {
125     SpaprDrc *drc;
126     bool hotplugged = spapr_drc_hotplugged(dev);
127 
128     drc = spapr_drc_by_id(TYPE_SPAPR_DRC_PMEM, slot);
129     g_assert(drc);
130 
131     /*
132      * pc_dimm_get_free_slot() provided a free slot at pre-plug. The
133      * corresponding DRC is thus assumed to be attachable.
134      */
135     spapr_drc_attach(drc, dev);
136 
137     if (hotplugged) {
138         spapr_hotplug_req_add_by_index(drc);
139     }
140 }
141 
142 static int spapr_dt_nvdimm(SpaprMachineState *spapr, void *fdt,
143                            int parent_offset, NVDIMMDevice *nvdimm)
144 {
145     int child_offset;
146     char *buf;
147     SpaprDrc *drc;
148     uint32_t drc_idx;
149     uint32_t node = object_property_get_uint(OBJECT(nvdimm), PC_DIMM_NODE_PROP,
150                                              &error_abort);
151     uint64_t slot = object_property_get_uint(OBJECT(nvdimm), PC_DIMM_SLOT_PROP,
152                                              &error_abort);
153     uint64_t lsize = nvdimm->label_size;
154     uint64_t size = object_property_get_int(OBJECT(nvdimm), PC_DIMM_SIZE_PROP,
155                                             NULL);
156 
157     drc = spapr_drc_by_id(TYPE_SPAPR_DRC_PMEM, slot);
158     g_assert(drc);
159 
160     drc_idx = spapr_drc_index(drc);
161 
162     buf = g_strdup_printf("ibm,pmemory@%x", drc_idx);
163     child_offset = fdt_add_subnode(fdt, parent_offset, buf);
164     g_free(buf);
165 
166     _FDT(child_offset);
167 
168     _FDT((fdt_setprop_cell(fdt, child_offset, "reg", drc_idx)));
169     _FDT((fdt_setprop_string(fdt, child_offset, "compatible", "ibm,pmemory")));
170     _FDT((fdt_setprop_string(fdt, child_offset, "device_type", "ibm,pmemory")));
171 
172     spapr_numa_write_associativity_dt(spapr, fdt, child_offset, node);
173 
174     buf = qemu_uuid_unparse_strdup(&nvdimm->uuid);
175     _FDT((fdt_setprop_string(fdt, child_offset, "ibm,unit-guid", buf)));
176     g_free(buf);
177 
178     _FDT((fdt_setprop_cell(fdt, child_offset, "ibm,my-drc-index", drc_idx)));
179 
180     _FDT((fdt_setprop_u64(fdt, child_offset, "ibm,block-size",
181                           SPAPR_MINIMUM_SCM_BLOCK_SIZE)));
182     _FDT((fdt_setprop_u64(fdt, child_offset, "ibm,number-of-blocks",
183                           size / SPAPR_MINIMUM_SCM_BLOCK_SIZE)));
184     _FDT((fdt_setprop_cell(fdt, child_offset, "ibm,metadata-size", lsize)));
185 
186     _FDT((fdt_setprop_string(fdt, child_offset, "ibm,pmem-application",
187                              "operating-system")));
188     _FDT(fdt_setprop(fdt, child_offset, "ibm,cache-flush-required", NULL, 0));
189 
190     if (object_dynamic_cast(OBJECT(nvdimm), TYPE_SPAPR_NVDIMM)) {
191         bool is_pmem = false, pmem_override = false;
192         PCDIMMDevice *dimm = PC_DIMM(nvdimm);
193         HostMemoryBackend *hostmem = dimm->hostmem;
194 
195         is_pmem = object_property_get_bool(OBJECT(hostmem), "pmem", NULL);
196         pmem_override = object_property_get_bool(OBJECT(nvdimm),
197                                                  "pmem-override", NULL);
198         if (!is_pmem || pmem_override) {
199             _FDT(fdt_setprop(fdt, child_offset, "ibm,hcall-flush-required",
200                              NULL, 0));
201         }
202     }
203 
204     return child_offset;
205 }
206 
207 int spapr_pmem_dt_populate(SpaprDrc *drc, SpaprMachineState *spapr,
208                            void *fdt, int *fdt_start_offset, Error **errp)
209 {
210     NVDIMMDevice *nvdimm = NVDIMM(drc->dev);
211 
212     *fdt_start_offset = spapr_dt_nvdimm(spapr, fdt, 0, nvdimm);
213 
214     return 0;
215 }
216 
217 void spapr_dt_persistent_memory(SpaprMachineState *spapr, void *fdt)
218 {
219     int offset = fdt_subnode_offset(fdt, 0, "ibm,persistent-memory");
220     GSList *iter, *nvdimms = nvdimm_get_device_list();
221 
222     if (offset < 0) {
223         offset = fdt_add_subnode(fdt, 0, "ibm,persistent-memory");
224         _FDT(offset);
225         _FDT((fdt_setprop_cell(fdt, offset, "#address-cells", 0x1)));
226         _FDT((fdt_setprop_cell(fdt, offset, "#size-cells", 0x0)));
227         _FDT((fdt_setprop_string(fdt, offset, "device_type",
228                                  "ibm,persistent-memory")));
229     }
230 
231     /* Create DT entries for cold plugged NVDIMM devices */
232     for (iter = nvdimms; iter; iter = iter->next) {
233         NVDIMMDevice *nvdimm = iter->data;
234 
235         spapr_dt_nvdimm(spapr, fdt, offset, nvdimm);
236     }
237     g_slist_free(nvdimms);
238 
239     return;
240 }
241 
242 static target_ulong h_scm_read_metadata(PowerPCCPU *cpu,
243                                         SpaprMachineState *spapr,
244                                         target_ulong opcode,
245                                         target_ulong *args)
246 {
247     uint32_t drc_index = args[0];
248     uint64_t offset = args[1];
249     uint64_t len = args[2];
250     SpaprDrc *drc = spapr_drc_by_index(drc_index);
251     NVDIMMDevice *nvdimm;
252     NVDIMMClass *ddc;
253     uint64_t data = 0;
254     uint8_t buf[8] = { 0 };
255 
256     if (!drc || !drc->dev ||
257         spapr_drc_type(drc) != SPAPR_DR_CONNECTOR_TYPE_PMEM) {
258         return H_PARAMETER;
259     }
260 
261     if (len != 1 && len != 2 &&
262         len != 4 && len != 8) {
263         return H_P3;
264     }
265 
266     nvdimm = NVDIMM(drc->dev);
267     if ((offset + len < offset) ||
268         (nvdimm->label_size < len + offset)) {
269         return H_P2;
270     }
271 
272     ddc = NVDIMM_GET_CLASS(nvdimm);
273     ddc->read_label_data(nvdimm, buf, len, offset);
274 
275     switch (len) {
276     case 1:
277         data = ldub_p(buf);
278         break;
279     case 2:
280         data = lduw_be_p(buf);
281         break;
282     case 4:
283         data = ldl_be_p(buf);
284         break;
285     case 8:
286         data = ldq_be_p(buf);
287         break;
288     default:
289         g_assert_not_reached();
290     }
291 
292     args[0] = data;
293 
294     return H_SUCCESS;
295 }
296 
297 static target_ulong h_scm_write_metadata(PowerPCCPU *cpu,
298                                          SpaprMachineState *spapr,
299                                          target_ulong opcode,
300                                          target_ulong *args)
301 {
302     uint32_t drc_index = args[0];
303     uint64_t offset = args[1];
304     uint64_t data = args[2];
305     uint64_t len = args[3];
306     SpaprDrc *drc = spapr_drc_by_index(drc_index);
307     NVDIMMDevice *nvdimm;
308     NVDIMMClass *ddc;
309     uint8_t buf[8] = { 0 };
310 
311     if (!drc || !drc->dev ||
312         spapr_drc_type(drc) != SPAPR_DR_CONNECTOR_TYPE_PMEM) {
313         return H_PARAMETER;
314     }
315 
316     if (len != 1 && len != 2 &&
317         len != 4 && len != 8) {
318         return H_P4;
319     }
320 
321     nvdimm = NVDIMM(drc->dev);
322     if ((offset + len < offset) ||
323         (nvdimm->label_size < len + offset)) {
324         return H_P2;
325     }
326 
327     switch (len) {
328     case 1:
329         if (data & 0xffffffffffffff00) {
330             return H_P2;
331         }
332         stb_p(buf, data);
333         break;
334     case 2:
335         if (data & 0xffffffffffff0000) {
336             return H_P2;
337         }
338         stw_be_p(buf, data);
339         break;
340     case 4:
341         if (data & 0xffffffff00000000) {
342             return H_P2;
343         }
344         stl_be_p(buf, data);
345         break;
346     case 8:
347         stq_be_p(buf, data);
348         break;
349     default:
350             g_assert_not_reached();
351     }
352 
353     ddc = NVDIMM_GET_CLASS(nvdimm);
354     ddc->write_label_data(nvdimm, buf, len, offset);
355 
356     return H_SUCCESS;
357 }
358 
359 static target_ulong h_scm_bind_mem(PowerPCCPU *cpu, SpaprMachineState *spapr,
360                                    target_ulong opcode, target_ulong *args)
361 {
362     uint32_t drc_index = args[0];
363     uint64_t starting_idx = args[1];
364     uint64_t no_of_scm_blocks_to_bind = args[2];
365     uint64_t target_logical_mem_addr = args[3];
366     uint64_t continue_token = args[4];
367     uint64_t size;
368     uint64_t total_no_of_scm_blocks;
369     SpaprDrc *drc = spapr_drc_by_index(drc_index);
370     hwaddr addr;
371     NVDIMMDevice *nvdimm;
372 
373     if (!drc || !drc->dev ||
374         spapr_drc_type(drc) != SPAPR_DR_CONNECTOR_TYPE_PMEM) {
375         return H_PARAMETER;
376     }
377 
378     /*
379      * Currently continue token should be zero qemu has already bound
380      * everything and this hcall doesnt return H_BUSY.
381      */
382     if (continue_token > 0) {
383         return H_P5;
384     }
385 
386     /* Currently qemu assigns the address. */
387     if (target_logical_mem_addr != 0xffffffffffffffff) {
388         return H_OVERLAP;
389     }
390 
391     nvdimm = NVDIMM(drc->dev);
392 
393     size = object_property_get_uint(OBJECT(nvdimm),
394                                     PC_DIMM_SIZE_PROP, &error_abort);
395 
396     total_no_of_scm_blocks = size / SPAPR_MINIMUM_SCM_BLOCK_SIZE;
397 
398     if (starting_idx > total_no_of_scm_blocks) {
399         return H_P2;
400     }
401 
402     if (((starting_idx + no_of_scm_blocks_to_bind) < starting_idx) ||
403         ((starting_idx + no_of_scm_blocks_to_bind) > total_no_of_scm_blocks)) {
404         return H_P3;
405     }
406 
407     addr = object_property_get_uint(OBJECT(nvdimm),
408                                     PC_DIMM_ADDR_PROP, &error_abort);
409 
410     addr += starting_idx * SPAPR_MINIMUM_SCM_BLOCK_SIZE;
411 
412     /* Already bound, Return target logical address in R5 */
413     args[1] = addr;
414     args[2] = no_of_scm_blocks_to_bind;
415 
416     return H_SUCCESS;
417 }
418 
419 typedef struct SpaprNVDIMMDeviceFlushState {
420     uint64_t continue_token;
421     int64_t hcall_ret;
422     uint32_t drcidx;
423 
424     QLIST_ENTRY(SpaprNVDIMMDeviceFlushState) node;
425 } SpaprNVDIMMDeviceFlushState;
426 
427 typedef struct SpaprNVDIMMDevice SpaprNVDIMMDevice;
428 struct SpaprNVDIMMDevice {
429     /* private */
430     NVDIMMDevice parent_obj;
431 
432     bool hcall_flush_required;
433     uint64_t nvdimm_flush_token;
434     QLIST_HEAD(, SpaprNVDIMMDeviceFlushState) pending_nvdimm_flush_states;
435     QLIST_HEAD(, SpaprNVDIMMDeviceFlushState) completed_nvdimm_flush_states;
436 
437     /* public */
438 
439     /*
440      * The 'on' value for this property forced the qemu to enable the hcall
441      * flush for the nvdimm device even if the backend is a pmem
442      */
443     bool pmem_override;
444 };
445 
446 static int flush_worker_cb(void *opaque)
447 {
448     SpaprNVDIMMDeviceFlushState *state = opaque;
449     SpaprDrc *drc = spapr_drc_by_index(state->drcidx);
450     PCDIMMDevice *dimm;
451     HostMemoryBackend *backend;
452     int backend_fd;
453 
454     g_assert(drc != NULL);
455 
456     dimm = PC_DIMM(drc->dev);
457     backend = MEMORY_BACKEND(dimm->hostmem);
458     backend_fd = memory_region_get_fd(&backend->mr);
459 
460     if (object_property_get_bool(OBJECT(backend), "pmem", NULL)) {
461         MemoryRegion *mr = host_memory_backend_get_memory(dimm->hostmem);
462         void *ptr = memory_region_get_ram_ptr(mr);
463         size_t size = object_property_get_uint(OBJECT(dimm), PC_DIMM_SIZE_PROP,
464                                                NULL);
465 
466         /* flush pmem backend */
467         pmem_persist(ptr, size);
468     } else {
469         /* flush raw backing image */
470         if (qemu_fdatasync(backend_fd) < 0) {
471             error_report("papr_scm: Could not sync nvdimm to backend file: %s",
472                          strerror(errno));
473             return H_HARDWARE;
474         }
475     }
476 
477     return H_SUCCESS;
478 }
479 
480 static void spapr_nvdimm_flush_completion_cb(void *opaque, int hcall_ret)
481 {
482     SpaprNVDIMMDeviceFlushState *state = opaque;
483     SpaprDrc *drc = spapr_drc_by_index(state->drcidx);
484     SpaprNVDIMMDevice *s_nvdimm;
485 
486     g_assert(drc != NULL);
487 
488     s_nvdimm = SPAPR_NVDIMM(drc->dev);
489 
490     state->hcall_ret = hcall_ret;
491     QLIST_REMOVE(state, node);
492     QLIST_INSERT_HEAD(&s_nvdimm->completed_nvdimm_flush_states, state, node);
493 }
494 
495 static int spapr_nvdimm_flush_post_load(void *opaque, int version_id)
496 {
497     SpaprNVDIMMDevice *s_nvdimm = (SpaprNVDIMMDevice *)opaque;
498     SpaprNVDIMMDeviceFlushState *state;
499     HostMemoryBackend *backend = MEMORY_BACKEND(PC_DIMM(s_nvdimm)->hostmem);
500     bool is_pmem = object_property_get_bool(OBJECT(backend), "pmem", NULL);
501     bool pmem_override = object_property_get_bool(OBJECT(s_nvdimm),
502                                                   "pmem-override", NULL);
503     bool dest_hcall_flush_required = pmem_override || !is_pmem;
504 
505     if (!s_nvdimm->hcall_flush_required && dest_hcall_flush_required) {
506         error_report("The file backend for the spapr-nvdimm device %s at "
507                      "source is a pmem, use pmem=on and pmem-override=off to "
508                      "continue.", DEVICE(s_nvdimm)->id);
509         return -EINVAL;
510     }
511     if (s_nvdimm->hcall_flush_required && !dest_hcall_flush_required) {
512         error_report("The guest expects hcall-flush support for the "
513                      "spapr-nvdimm device %s, use pmem_override=on to "
514                      "continue.", DEVICE(s_nvdimm)->id);
515         return -EINVAL;
516     }
517 
518     QLIST_FOREACH(state, &s_nvdimm->pending_nvdimm_flush_states, node) {
519         thread_pool_submit_aio(flush_worker_cb, state,
520                                spapr_nvdimm_flush_completion_cb, state);
521     }
522 
523     return 0;
524 }
525 
526 static const VMStateDescription vmstate_spapr_nvdimm_flush_state = {
527      .name = "spapr_nvdimm_flush_state",
528      .version_id = 1,
529      .minimum_version_id = 1,
530      .fields = (VMStateField[]) {
531          VMSTATE_UINT64(continue_token, SpaprNVDIMMDeviceFlushState),
532          VMSTATE_INT64(hcall_ret, SpaprNVDIMMDeviceFlushState),
533          VMSTATE_UINT32(drcidx, SpaprNVDIMMDeviceFlushState),
534          VMSTATE_END_OF_LIST()
535      },
536 };
537 
538 const VMStateDescription vmstate_spapr_nvdimm_states = {
539     .name = "spapr_nvdimm_states",
540     .version_id = 1,
541     .minimum_version_id = 1,
542     .post_load = spapr_nvdimm_flush_post_load,
543     .fields = (VMStateField[]) {
544         VMSTATE_BOOL(hcall_flush_required, SpaprNVDIMMDevice),
545         VMSTATE_UINT64(nvdimm_flush_token, SpaprNVDIMMDevice),
546         VMSTATE_QLIST_V(completed_nvdimm_flush_states, SpaprNVDIMMDevice, 1,
547                         vmstate_spapr_nvdimm_flush_state,
548                         SpaprNVDIMMDeviceFlushState, node),
549         VMSTATE_QLIST_V(pending_nvdimm_flush_states, SpaprNVDIMMDevice, 1,
550                         vmstate_spapr_nvdimm_flush_state,
551                         SpaprNVDIMMDeviceFlushState, node),
552         VMSTATE_END_OF_LIST()
553     },
554 };
555 
556 /*
557  * Assign a token and reserve it for the new flush state.
558  */
559 static SpaprNVDIMMDeviceFlushState *spapr_nvdimm_init_new_flush_state(
560                                                 SpaprNVDIMMDevice *spapr_nvdimm)
561 {
562     SpaprNVDIMMDeviceFlushState *state;
563 
564     state = g_malloc0(sizeof(*state));
565 
566     spapr_nvdimm->nvdimm_flush_token++;
567     /* Token zero is presumed as no job pending. Assert on overflow to zero */
568     g_assert(spapr_nvdimm->nvdimm_flush_token != 0);
569 
570     state->continue_token = spapr_nvdimm->nvdimm_flush_token;
571 
572     QLIST_INSERT_HEAD(&spapr_nvdimm->pending_nvdimm_flush_states, state, node);
573 
574     return state;
575 }
576 
577 /*
578  * spapr_nvdimm_finish_flushes
579  *      Waits for all pending flush requests to complete
580  *      their execution and free the states
581  */
582 void spapr_nvdimm_finish_flushes(void)
583 {
584     SpaprNVDIMMDeviceFlushState *state, *next;
585     GSList *list, *nvdimms;
586 
587     /*
588      * Called on reset path, the main loop thread which calls
589      * the pending BHs has gotten out running in the reset path,
590      * finally reaching here. Other code path being guest
591      * h_client_architecture_support, thats early boot up.
592      */
593     nvdimms = nvdimm_get_device_list();
594     for (list = nvdimms; list; list = list->next) {
595         NVDIMMDevice *nvdimm = list->data;
596         if (object_dynamic_cast(OBJECT(nvdimm), TYPE_SPAPR_NVDIMM)) {
597             SpaprNVDIMMDevice *s_nvdimm = SPAPR_NVDIMM(nvdimm);
598             while (!QLIST_EMPTY(&s_nvdimm->pending_nvdimm_flush_states)) {
599                 aio_poll(qemu_get_aio_context(), true);
600             }
601 
602             QLIST_FOREACH_SAFE(state, &s_nvdimm->completed_nvdimm_flush_states,
603                                node, next) {
604                 QLIST_REMOVE(state, node);
605                 g_free(state);
606             }
607         }
608     }
609     g_slist_free(nvdimms);
610 }
611 
612 /*
613  * spapr_nvdimm_get_flush_status
614  *      Fetches the status of the hcall worker and returns
615  *      H_LONG_BUSY_ORDER_10_MSEC if the worker is still running.
616  */
617 static int spapr_nvdimm_get_flush_status(SpaprNVDIMMDevice *s_nvdimm,
618                                          uint64_t token)
619 {
620     SpaprNVDIMMDeviceFlushState *state, *node;
621 
622     QLIST_FOREACH(state, &s_nvdimm->pending_nvdimm_flush_states, node) {
623         if (state->continue_token == token) {
624             return H_LONG_BUSY_ORDER_10_MSEC;
625         }
626     }
627 
628     QLIST_FOREACH_SAFE(state, &s_nvdimm->completed_nvdimm_flush_states,
629                        node, node) {
630         if (state->continue_token == token) {
631             int ret = state->hcall_ret;
632             QLIST_REMOVE(state, node);
633             g_free(state);
634             return ret;
635         }
636     }
637 
638     /* If not found in complete list too, invalid token */
639     return H_P2;
640 }
641 
642 /*
643  * H_SCM_FLUSH
644  * Input: drc_index, continue-token
645  * Out: continue-token
646  * Return Value: H_SUCCESS, H_Parameter, H_P2, H_LONG_BUSY_ORDER_10_MSEC,
647  *               H_UNSUPPORTED
648  *
649  * Given a DRC Index Flush the data to backend NVDIMM device. The hcall returns
650  * H_LONG_BUSY_ORDER_10_MSEC when the flush takes longer time and the hcall
651  * needs to be issued multiple times in order to be completely serviced. The
652  * continue-token from the output to be passed in the argument list of
653  * subsequent hcalls until the hcall is completely serviced at which point
654  * H_SUCCESS or other error is returned.
655  */
656 static target_ulong h_scm_flush(PowerPCCPU *cpu, SpaprMachineState *spapr,
657                                 target_ulong opcode, target_ulong *args)
658 {
659     int ret;
660     uint32_t drc_index = args[0];
661     uint64_t continue_token = args[1];
662     SpaprDrc *drc = spapr_drc_by_index(drc_index);
663     PCDIMMDevice *dimm;
664     HostMemoryBackend *backend = NULL;
665     SpaprNVDIMMDeviceFlushState *state;
666     int fd;
667 
668     if (!drc || !drc->dev ||
669         spapr_drc_type(drc) != SPAPR_DR_CONNECTOR_TYPE_PMEM) {
670         return H_PARAMETER;
671     }
672 
673     dimm = PC_DIMM(drc->dev);
674     if (!object_dynamic_cast(OBJECT(dimm), TYPE_SPAPR_NVDIMM)) {
675         return H_PARAMETER;
676     }
677     if (continue_token == 0) {
678         bool is_pmem = false, pmem_override = false;
679         backend = MEMORY_BACKEND(dimm->hostmem);
680         fd = memory_region_get_fd(&backend->mr);
681 
682         if (fd < 0) {
683             return H_UNSUPPORTED;
684         }
685 
686         is_pmem = object_property_get_bool(OBJECT(backend), "pmem", NULL);
687         pmem_override = object_property_get_bool(OBJECT(dimm),
688                                                 "pmem-override", NULL);
689         if (is_pmem && !pmem_override) {
690             return H_UNSUPPORTED;
691         }
692 
693         state = spapr_nvdimm_init_new_flush_state(SPAPR_NVDIMM(dimm));
694         if (!state) {
695             return H_HARDWARE;
696         }
697 
698         state->drcidx = drc_index;
699 
700         thread_pool_submit_aio(flush_worker_cb, state,
701                                spapr_nvdimm_flush_completion_cb, state);
702 
703         continue_token = state->continue_token;
704     }
705 
706     ret = spapr_nvdimm_get_flush_status(SPAPR_NVDIMM(dimm), continue_token);
707     if (H_IS_LONG_BUSY(ret)) {
708         args[0] = continue_token;
709     }
710 
711     return ret;
712 }
713 
714 static target_ulong h_scm_unbind_mem(PowerPCCPU *cpu, SpaprMachineState *spapr,
715                                      target_ulong opcode, target_ulong *args)
716 {
717     uint32_t drc_index = args[0];
718     uint64_t starting_scm_logical_addr = args[1];
719     uint64_t no_of_scm_blocks_to_unbind = args[2];
720     uint64_t continue_token = args[3];
721     uint64_t size_to_unbind;
722     Range blockrange = range_empty;
723     Range nvdimmrange = range_empty;
724     SpaprDrc *drc = spapr_drc_by_index(drc_index);
725     NVDIMMDevice *nvdimm;
726     uint64_t size, addr;
727 
728     if (!drc || !drc->dev ||
729         spapr_drc_type(drc) != SPAPR_DR_CONNECTOR_TYPE_PMEM) {
730         return H_PARAMETER;
731     }
732 
733     /* continue_token should be zero as this hcall doesn't return H_BUSY. */
734     if (continue_token > 0) {
735         return H_P4;
736     }
737 
738     /* Check if starting_scm_logical_addr is block aligned */
739     if (!QEMU_IS_ALIGNED(starting_scm_logical_addr,
740                          SPAPR_MINIMUM_SCM_BLOCK_SIZE)) {
741         return H_P2;
742     }
743 
744     size_to_unbind = no_of_scm_blocks_to_unbind * SPAPR_MINIMUM_SCM_BLOCK_SIZE;
745     if (no_of_scm_blocks_to_unbind == 0 || no_of_scm_blocks_to_unbind !=
746                                size_to_unbind / SPAPR_MINIMUM_SCM_BLOCK_SIZE) {
747         return H_P3;
748     }
749 
750     nvdimm = NVDIMM(drc->dev);
751     size = object_property_get_int(OBJECT(nvdimm), PC_DIMM_SIZE_PROP,
752                                    &error_abort);
753     addr = object_property_get_int(OBJECT(nvdimm), PC_DIMM_ADDR_PROP,
754                                    &error_abort);
755 
756     range_init_nofail(&nvdimmrange, addr, size);
757     range_init_nofail(&blockrange, starting_scm_logical_addr, size_to_unbind);
758 
759     if (!range_contains_range(&nvdimmrange, &blockrange)) {
760         return H_P3;
761     }
762 
763     args[1] = no_of_scm_blocks_to_unbind;
764 
765     /* let unplug take care of actual unbind */
766     return H_SUCCESS;
767 }
768 
769 #define H_UNBIND_SCOPE_ALL 0x1
770 #define H_UNBIND_SCOPE_DRC 0x2
771 
772 static target_ulong h_scm_unbind_all(PowerPCCPU *cpu, SpaprMachineState *spapr,
773                                      target_ulong opcode, target_ulong *args)
774 {
775     uint64_t target_scope = args[0];
776     uint32_t drc_index = args[1];
777     uint64_t continue_token = args[2];
778     NVDIMMDevice *nvdimm;
779     uint64_t size;
780     uint64_t no_of_scm_blocks_unbound = 0;
781 
782     /* continue_token should be zero as this hcall doesn't return H_BUSY. */
783     if (continue_token > 0) {
784         return H_P4;
785     }
786 
787     if (target_scope == H_UNBIND_SCOPE_DRC) {
788         SpaprDrc *drc = spapr_drc_by_index(drc_index);
789 
790         if (!drc || !drc->dev ||
791             spapr_drc_type(drc) != SPAPR_DR_CONNECTOR_TYPE_PMEM) {
792             return H_P2;
793         }
794 
795         nvdimm = NVDIMM(drc->dev);
796         size = object_property_get_int(OBJECT(nvdimm), PC_DIMM_SIZE_PROP,
797                                        &error_abort);
798 
799         no_of_scm_blocks_unbound = size / SPAPR_MINIMUM_SCM_BLOCK_SIZE;
800     } else if (target_scope ==  H_UNBIND_SCOPE_ALL) {
801         GSList *list, *nvdimms;
802 
803         nvdimms = nvdimm_get_device_list();
804         for (list = nvdimms; list; list = list->next) {
805             nvdimm = list->data;
806             size = object_property_get_int(OBJECT(nvdimm), PC_DIMM_SIZE_PROP,
807                                            &error_abort);
808 
809             no_of_scm_blocks_unbound += size / SPAPR_MINIMUM_SCM_BLOCK_SIZE;
810         }
811         g_slist_free(nvdimms);
812     } else {
813         return H_PARAMETER;
814     }
815 
816     args[1] = no_of_scm_blocks_unbound;
817 
818     /* let unplug take care of actual unbind */
819     return H_SUCCESS;
820 }
821 
822 static target_ulong h_scm_health(PowerPCCPU *cpu, SpaprMachineState *spapr,
823                                  target_ulong opcode, target_ulong *args)
824 {
825 
826     NVDIMMDevice *nvdimm;
827     uint64_t hbitmap = 0;
828     uint32_t drc_index = args[0];
829     SpaprDrc *drc = spapr_drc_by_index(drc_index);
830     const uint64_t hbitmap_mask = PAPR_PMEM_UNARMED;
831 
832 
833     /* Ensure that the drc is valid & is valid PMEM dimm and is plugged in */
834     if (!drc || !drc->dev ||
835         spapr_drc_type(drc) != SPAPR_DR_CONNECTOR_TYPE_PMEM) {
836         return H_PARAMETER;
837     }
838 
839     nvdimm = NVDIMM(drc->dev);
840 
841     /* Update if the nvdimm is unarmed and send its status via health bitmaps */
842     if (object_property_get_bool(OBJECT(nvdimm), NVDIMM_UNARMED_PROP, NULL)) {
843         hbitmap |= PAPR_PMEM_UNARMED;
844     }
845 
846     /* Update the out args with health bitmap/mask */
847     args[0] = hbitmap;
848     args[1] = hbitmap_mask;
849 
850     return H_SUCCESS;
851 }
852 
853 static void spapr_scm_register_types(void)
854 {
855     /* qemu/scm specific hcalls */
856     spapr_register_hypercall(H_SCM_READ_METADATA, h_scm_read_metadata);
857     spapr_register_hypercall(H_SCM_WRITE_METADATA, h_scm_write_metadata);
858     spapr_register_hypercall(H_SCM_BIND_MEM, h_scm_bind_mem);
859     spapr_register_hypercall(H_SCM_UNBIND_MEM, h_scm_unbind_mem);
860     spapr_register_hypercall(H_SCM_UNBIND_ALL, h_scm_unbind_all);
861     spapr_register_hypercall(H_SCM_HEALTH, h_scm_health);
862     spapr_register_hypercall(H_SCM_FLUSH, h_scm_flush);
863 }
864 
865 type_init(spapr_scm_register_types)
866 
867 static void spapr_nvdimm_realize(NVDIMMDevice *dimm, Error **errp)
868 {
869     SpaprNVDIMMDevice *s_nvdimm = SPAPR_NVDIMM(dimm);
870     HostMemoryBackend *backend = MEMORY_BACKEND(PC_DIMM(dimm)->hostmem);
871     bool is_pmem = object_property_get_bool(OBJECT(backend),  "pmem", NULL);
872     bool pmem_override = object_property_get_bool(OBJECT(dimm), "pmem-override",
873                                              NULL);
874     if (!is_pmem || pmem_override) {
875         s_nvdimm->hcall_flush_required = true;
876     }
877 
878     vmstate_register(NULL, VMSTATE_INSTANCE_ID_ANY,
879                      &vmstate_spapr_nvdimm_states, dimm);
880 }
881 
882 static void spapr_nvdimm_unrealize(NVDIMMDevice *dimm)
883 {
884     vmstate_unregister(NULL, &vmstate_spapr_nvdimm_states, dimm);
885 }
886 
887 static Property spapr_nvdimm_properties[] = {
888 #ifdef CONFIG_LIBPMEM
889     DEFINE_PROP_BOOL("pmem-override", SpaprNVDIMMDevice, pmem_override, false),
890 #endif
891     DEFINE_PROP_END_OF_LIST(),
892 };
893 
894 static void spapr_nvdimm_class_init(ObjectClass *oc, void *data)
895 {
896     DeviceClass *dc = DEVICE_CLASS(oc);
897     NVDIMMClass *nvc = NVDIMM_CLASS(oc);
898 
899     nvc->realize = spapr_nvdimm_realize;
900     nvc->unrealize = spapr_nvdimm_unrealize;
901 
902     device_class_set_props(dc, spapr_nvdimm_properties);
903 }
904 
905 static void spapr_nvdimm_init(Object *obj)
906 {
907     SpaprNVDIMMDevice *s_nvdimm = SPAPR_NVDIMM(obj);
908 
909     s_nvdimm->hcall_flush_required = false;
910     QLIST_INIT(&s_nvdimm->pending_nvdimm_flush_states);
911     QLIST_INIT(&s_nvdimm->completed_nvdimm_flush_states);
912 }
913 
914 static TypeInfo spapr_nvdimm_info = {
915     .name          = TYPE_SPAPR_NVDIMM,
916     .parent        = TYPE_NVDIMM,
917     .class_init    = spapr_nvdimm_class_init,
918     .class_size    = sizeof(SPAPRNVDIMMClass),
919     .instance_size = sizeof(SpaprNVDIMMDevice),
920     .instance_init = spapr_nvdimm_init,
921 };
922 
923 static void spapr_nvdimm_register_types(void)
924 {
925     type_register_static(&spapr_nvdimm_info);
926 }
927 
928 type_init(spapr_nvdimm_register_types)
929