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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2021, NVIDIA CORPORATION & AFFILIATES. All rights reserved
4 *
5 * Copyright (C) 2012 Red Hat, Inc. All rights reserved.
6 * Author: Alex Williamson <alex.williamson@redhat.com>
7 *
8 * Derived from original vfio:
9 * Copyright 2010 Cisco Systems, Inc. All rights reserved.
10 * Author: Tom Lyon, pugs@cisco.com
11 */
12
13#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14
15#include <linux/device.h>
16#include <linux/eventfd.h>
17#include <linux/file.h>
18#include <linux/interrupt.h>
19#include <linux/iommu.h>
20#include <linux/module.h>
21#include <linux/mutex.h>
22#include <linux/notifier.h>
23#include <linux/pm_runtime.h>
24#include <linux/slab.h>
25#include <linux/types.h>
26#include <linux/uaccess.h>
27
28#include "vfio_pci_priv.h"
29
30#define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
31#define DRIVER_DESC "VFIO PCI - User Level meta-driver"
32
33static char ids[1024] __initdata;
34module_param_string(ids, ids, sizeof(ids), 0);
35MODULE_PARM_DESC(ids, "Initial PCI IDs to add to the vfio driver, format is \"vendor:device[:subvendor[:subdevice[:class[:class_mask]]]]\" and multiple comma separated entries can be specified");
36
37static bool nointxmask;
38module_param_named(nointxmask, nointxmask, bool, S_IRUGO | S_IWUSR);
39MODULE_PARM_DESC(nointxmask,
40 "Disable support for PCI 2.3 style INTx masking. If this resolves problems for specific devices, report lspci -vvvxxx to linux-pci@vger.kernel.org so the device can be fixed automatically via the broken_intx_masking flag.");
41
42#ifdef CONFIG_VFIO_PCI_VGA
43static bool disable_vga;
44module_param(disable_vga, bool, S_IRUGO);
45MODULE_PARM_DESC(disable_vga, "Disable VGA resource access through vfio-pci");
46#endif
47
48static bool disable_idle_d3;
49module_param(disable_idle_d3, bool, S_IRUGO | S_IWUSR);
50MODULE_PARM_DESC(disable_idle_d3,
51 "Disable using the PCI D3 low power state for idle, unused devices");
52
53static bool enable_sriov;
54#ifdef CONFIG_PCI_IOV
55module_param(enable_sriov, bool, 0644);
56MODULE_PARM_DESC(enable_sriov, "Enable support for SR-IOV configuration. Enabling SR-IOV on a PF typically requires support of the userspace PF driver, enabling VFs without such support may result in non-functional VFs or PF.");
57#endif
58
59static bool disable_denylist;
60module_param(disable_denylist, bool, 0444);
61MODULE_PARM_DESC(disable_denylist, "Disable use of device denylist. Disabling the denylist allows binding to devices with known errata that may lead to exploitable stability or security issues when accessed by untrusted users.");
62
63static bool vfio_pci_dev_in_denylist(struct pci_dev *pdev)
64{
65 switch (pdev->vendor) {
66 case PCI_VENDOR_ID_INTEL:
67 switch (pdev->device) {
68 case PCI_DEVICE_ID_INTEL_QAT_C3XXX:
69 case PCI_DEVICE_ID_INTEL_QAT_C3XXX_VF:
70 case PCI_DEVICE_ID_INTEL_QAT_C62X:
71 case PCI_DEVICE_ID_INTEL_QAT_C62X_VF:
72 case PCI_DEVICE_ID_INTEL_QAT_DH895XCC:
73 case PCI_DEVICE_ID_INTEL_QAT_DH895XCC_VF:
74 return true;
75 default:
76 return false;
77 }
78 }
79
80 return false;
81}
82
83static bool vfio_pci_is_denylisted(struct pci_dev *pdev)
84{
85 if (!vfio_pci_dev_in_denylist(pdev))
86 return false;
87
88 if (disable_denylist) {
89 pci_warn(pdev,
90 "device denylist disabled - allowing device %04x:%04x.\n",
91 pdev->vendor, pdev->device);
92 return false;
93 }
94
95 pci_warn(pdev, "%04x:%04x exists in vfio-pci device denylist, driver probing disallowed.\n",
96 pdev->vendor, pdev->device);
97
98 return true;
99}
100
101static int vfio_pci_open_device(struct vfio_device *core_vdev)
102{
103 struct vfio_pci_core_device *vdev =
104 container_of(core_vdev, struct vfio_pci_core_device, vdev);
105 struct pci_dev *pdev = vdev->pdev;
106 int ret;
107
108 ret = vfio_pci_core_enable(vdev);
109 if (ret)
110 return ret;
111
112 if (vfio_pci_is_vga(pdev) &&
113 pdev->vendor == PCI_VENDOR_ID_INTEL &&
114 IS_ENABLED(CONFIG_VFIO_PCI_IGD)) {
115 ret = vfio_pci_igd_init(vdev);
116 if (ret && ret != -ENODEV) {
117 pci_warn(pdev, "Failed to setup Intel IGD regions\n");
118 vfio_pci_core_disable(vdev);
119 return ret;
120 }
121 }
122
123 vfio_pci_core_finish_enable(vdev);
124
125 return 0;
126}
127
128static const struct vfio_device_ops vfio_pci_ops = {
129 .name = "vfio-pci",
130 .init = vfio_pci_core_init_dev,
131 .release = vfio_pci_core_release_dev,
132 .open_device = vfio_pci_open_device,
133 .close_device = vfio_pci_core_close_device,
134 .ioctl = vfio_pci_core_ioctl,
135 .device_feature = vfio_pci_core_ioctl_feature,
136 .read = vfio_pci_core_read,
137 .write = vfio_pci_core_write,
138 .mmap = vfio_pci_core_mmap,
139 .request = vfio_pci_core_request,
140 .match = vfio_pci_core_match,
141 .bind_iommufd = vfio_iommufd_physical_bind,
142 .unbind_iommufd = vfio_iommufd_physical_unbind,
143 .attach_ioas = vfio_iommufd_physical_attach_ioas,
144 .detach_ioas = vfio_iommufd_physical_detach_ioas,
145};
146
147static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
148{
149 struct vfio_pci_core_device *vdev;
150 int ret;
151
152 if (vfio_pci_is_denylisted(pdev))
153 return -EINVAL;
154
155 vdev = vfio_alloc_device(vfio_pci_core_device, vdev, &pdev->dev,
156 &vfio_pci_ops);
157 if (IS_ERR(vdev))
158 return PTR_ERR(vdev);
159
160 dev_set_drvdata(&pdev->dev, vdev);
161 ret = vfio_pci_core_register_device(vdev);
162 if (ret)
163 goto out_put_vdev;
164 return 0;
165
166out_put_vdev:
167 vfio_put_device(&vdev->vdev);
168 return ret;
169}
170
171static void vfio_pci_remove(struct pci_dev *pdev)
172{
173 struct vfio_pci_core_device *vdev = dev_get_drvdata(&pdev->dev);
174
175 vfio_pci_core_unregister_device(vdev);
176 vfio_put_device(&vdev->vdev);
177}
178
179static int vfio_pci_sriov_configure(struct pci_dev *pdev, int nr_virtfn)
180{
181 struct vfio_pci_core_device *vdev = dev_get_drvdata(&pdev->dev);
182
183 if (!enable_sriov)
184 return -ENOENT;
185
186 return vfio_pci_core_sriov_configure(vdev, nr_virtfn);
187}
188
189static const struct pci_device_id vfio_pci_table[] = {
190 { PCI_DRIVER_OVERRIDE_DEVICE_VFIO(PCI_ANY_ID, PCI_ANY_ID) }, /* match all by default */
191 {}
192};
193
194MODULE_DEVICE_TABLE(pci, vfio_pci_table);
195
196static struct pci_driver vfio_pci_driver = {
197 .name = "vfio-pci",
198 .id_table = vfio_pci_table,
199 .probe = vfio_pci_probe,
200 .remove = vfio_pci_remove,
201 .sriov_configure = vfio_pci_sriov_configure,
202 .err_handler = &vfio_pci_core_err_handlers,
203 .driver_managed_dma = true,
204};
205
206static void __init vfio_pci_fill_ids(void)
207{
208 char *p, *id;
209 int rc;
210
211 /* no ids passed actually */
212 if (ids[0] == '\0')
213 return;
214
215 /* add ids specified in the module parameter */
216 p = ids;
217 while ((id = strsep(&p, ","))) {
218 unsigned int vendor, device, subvendor = PCI_ANY_ID,
219 subdevice = PCI_ANY_ID, class = 0, class_mask = 0;
220 int fields;
221
222 if (!strlen(id))
223 continue;
224
225 fields = sscanf(id, "%x:%x:%x:%x:%x:%x",
226 &vendor, &device, &subvendor, &subdevice,
227 &class, &class_mask);
228
229 if (fields < 2) {
230 pr_warn("invalid id string \"%s\"\n", id);
231 continue;
232 }
233
234 rc = pci_add_dynid(&vfio_pci_driver, vendor, device,
235 subvendor, subdevice, class, class_mask, 0);
236 if (rc)
237 pr_warn("failed to add dynamic id [%04x:%04x[%04x:%04x]] class %#08x/%08x (%d)\n",
238 vendor, device, subvendor, subdevice,
239 class, class_mask, rc);
240 else
241 pr_info("add [%04x:%04x[%04x:%04x]] class %#08x/%08x\n",
242 vendor, device, subvendor, subdevice,
243 class, class_mask);
244 }
245}
246
247static int __init vfio_pci_init(void)
248{
249 int ret;
250 bool is_disable_vga = true;
251
252#ifdef CONFIG_VFIO_PCI_VGA
253 is_disable_vga = disable_vga;
254#endif
255
256 vfio_pci_core_set_params(nointxmask, is_disable_vga, disable_idle_d3);
257
258 /* Register and scan for devices */
259 ret = pci_register_driver(&vfio_pci_driver);
260 if (ret)
261 return ret;
262
263 vfio_pci_fill_ids();
264
265 if (disable_denylist)
266 pr_warn("device denylist disabled.\n");
267
268 return 0;
269}
270module_init(vfio_pci_init);
271
272static void __exit vfio_pci_cleanup(void)
273{
274 pci_unregister_driver(&vfio_pci_driver);
275}
276module_exit(vfio_pci_cleanup);
277
278MODULE_LICENSE("GPL v2");
279MODULE_AUTHOR(DRIVER_AUTHOR);
280MODULE_DESCRIPTION(DRIVER_DESC);
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2012 Red Hat, Inc. All rights reserved.
4 * Author: Alex Williamson <alex.williamson@redhat.com>
5 *
6 * Derived from original vfio:
7 * Copyright 2010 Cisco Systems, Inc. All rights reserved.
8 * Author: Tom Lyon, pugs@cisco.com
9 */
10
11#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12
13#include <linux/device.h>
14#include <linux/eventfd.h>
15#include <linux/file.h>
16#include <linux/interrupt.h>
17#include <linux/iommu.h>
18#include <linux/module.h>
19#include <linux/mutex.h>
20#include <linux/notifier.h>
21#include <linux/pci.h>
22#include <linux/pm_runtime.h>
23#include <linux/slab.h>
24#include <linux/types.h>
25#include <linux/uaccess.h>
26#include <linux/vfio.h>
27#include <linux/vgaarb.h>
28#include <linux/nospec.h>
29#include <linux/sched/mm.h>
30
31#include "vfio_pci_private.h"
32
33#define DRIVER_VERSION "0.2"
34#define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
35#define DRIVER_DESC "VFIO PCI - User Level meta-driver"
36
37static char ids[1024] __initdata;
38module_param_string(ids, ids, sizeof(ids), 0);
39MODULE_PARM_DESC(ids, "Initial PCI IDs to add to the vfio driver, format is \"vendor:device[:subvendor[:subdevice[:class[:class_mask]]]]\" and multiple comma separated entries can be specified");
40
41static bool nointxmask;
42module_param_named(nointxmask, nointxmask, bool, S_IRUGO | S_IWUSR);
43MODULE_PARM_DESC(nointxmask,
44 "Disable support for PCI 2.3 style INTx masking. If this resolves problems for specific devices, report lspci -vvvxxx to linux-pci@vger.kernel.org so the device can be fixed automatically via the broken_intx_masking flag.");
45
46#ifdef CONFIG_VFIO_PCI_VGA
47static bool disable_vga;
48module_param(disable_vga, bool, S_IRUGO);
49MODULE_PARM_DESC(disable_vga, "Disable VGA resource access through vfio-pci");
50#endif
51
52static bool disable_idle_d3;
53module_param(disable_idle_d3, bool, S_IRUGO | S_IWUSR);
54MODULE_PARM_DESC(disable_idle_d3,
55 "Disable using the PCI D3 low power state for idle, unused devices");
56
57static bool enable_sriov;
58#ifdef CONFIG_PCI_IOV
59module_param(enable_sriov, bool, 0644);
60MODULE_PARM_DESC(enable_sriov, "Enable support for SR-IOV configuration. Enabling SR-IOV on a PF typically requires support of the userspace PF driver, enabling VFs without such support may result in non-functional VFs or PF.");
61#endif
62
63static bool disable_denylist;
64module_param(disable_denylist, bool, 0444);
65MODULE_PARM_DESC(disable_denylist, "Disable use of device denylist. Disabling the denylist allows binding to devices with known errata that may lead to exploitable stability or security issues when accessed by untrusted users.");
66
67static inline bool vfio_vga_disabled(void)
68{
69#ifdef CONFIG_VFIO_PCI_VGA
70 return disable_vga;
71#else
72 return true;
73#endif
74}
75
76static bool vfio_pci_dev_in_denylist(struct pci_dev *pdev)
77{
78 switch (pdev->vendor) {
79 case PCI_VENDOR_ID_INTEL:
80 switch (pdev->device) {
81 case PCI_DEVICE_ID_INTEL_QAT_C3XXX:
82 case PCI_DEVICE_ID_INTEL_QAT_C3XXX_VF:
83 case PCI_DEVICE_ID_INTEL_QAT_C62X:
84 case PCI_DEVICE_ID_INTEL_QAT_C62X_VF:
85 case PCI_DEVICE_ID_INTEL_QAT_DH895XCC:
86 case PCI_DEVICE_ID_INTEL_QAT_DH895XCC_VF:
87 return true;
88 default:
89 return false;
90 }
91 }
92
93 return false;
94}
95
96static bool vfio_pci_is_denylisted(struct pci_dev *pdev)
97{
98 if (!vfio_pci_dev_in_denylist(pdev))
99 return false;
100
101 if (disable_denylist) {
102 pci_warn(pdev,
103 "device denylist disabled - allowing device %04x:%04x.\n",
104 pdev->vendor, pdev->device);
105 return false;
106 }
107
108 pci_warn(pdev, "%04x:%04x exists in vfio-pci device denylist, driver probing disallowed.\n",
109 pdev->vendor, pdev->device);
110
111 return true;
112}
113
114/*
115 * Our VGA arbiter participation is limited since we don't know anything
116 * about the device itself. However, if the device is the only VGA device
117 * downstream of a bridge and VFIO VGA support is disabled, then we can
118 * safely return legacy VGA IO and memory as not decoded since the user
119 * has no way to get to it and routing can be disabled externally at the
120 * bridge.
121 */
122static unsigned int vfio_pci_set_vga_decode(void *opaque, bool single_vga)
123{
124 struct vfio_pci_device *vdev = opaque;
125 struct pci_dev *tmp = NULL, *pdev = vdev->pdev;
126 unsigned char max_busnr;
127 unsigned int decodes;
128
129 if (single_vga || !vfio_vga_disabled() || pci_is_root_bus(pdev->bus))
130 return VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM |
131 VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM;
132
133 max_busnr = pci_bus_max_busnr(pdev->bus);
134 decodes = VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM;
135
136 while ((tmp = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, tmp)) != NULL) {
137 if (tmp == pdev ||
138 pci_domain_nr(tmp->bus) != pci_domain_nr(pdev->bus) ||
139 pci_is_root_bus(tmp->bus))
140 continue;
141
142 if (tmp->bus->number >= pdev->bus->number &&
143 tmp->bus->number <= max_busnr) {
144 pci_dev_put(tmp);
145 decodes |= VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM;
146 break;
147 }
148 }
149
150 return decodes;
151}
152
153static inline bool vfio_pci_is_vga(struct pci_dev *pdev)
154{
155 return (pdev->class >> 8) == PCI_CLASS_DISPLAY_VGA;
156}
157
158static void vfio_pci_probe_mmaps(struct vfio_pci_device *vdev)
159{
160 struct resource *res;
161 int i;
162 struct vfio_pci_dummy_resource *dummy_res;
163
164 INIT_LIST_HEAD(&vdev->dummy_resources_list);
165
166 for (i = 0; i < PCI_STD_NUM_BARS; i++) {
167 int bar = i + PCI_STD_RESOURCES;
168
169 res = &vdev->pdev->resource[bar];
170
171 if (!IS_ENABLED(CONFIG_VFIO_PCI_MMAP))
172 goto no_mmap;
173
174 if (!(res->flags & IORESOURCE_MEM))
175 goto no_mmap;
176
177 /*
178 * The PCI core shouldn't set up a resource with a
179 * type but zero size. But there may be bugs that
180 * cause us to do that.
181 */
182 if (!resource_size(res))
183 goto no_mmap;
184
185 if (resource_size(res) >= PAGE_SIZE) {
186 vdev->bar_mmap_supported[bar] = true;
187 continue;
188 }
189
190 if (!(res->start & ~PAGE_MASK)) {
191 /*
192 * Add a dummy resource to reserve the remainder
193 * of the exclusive page in case that hot-add
194 * device's bar is assigned into it.
195 */
196 dummy_res = kzalloc(sizeof(*dummy_res), GFP_KERNEL);
197 if (dummy_res == NULL)
198 goto no_mmap;
199
200 dummy_res->resource.name = "vfio sub-page reserved";
201 dummy_res->resource.start = res->end + 1;
202 dummy_res->resource.end = res->start + PAGE_SIZE - 1;
203 dummy_res->resource.flags = res->flags;
204 if (request_resource(res->parent,
205 &dummy_res->resource)) {
206 kfree(dummy_res);
207 goto no_mmap;
208 }
209 dummy_res->index = bar;
210 list_add(&dummy_res->res_next,
211 &vdev->dummy_resources_list);
212 vdev->bar_mmap_supported[bar] = true;
213 continue;
214 }
215 /*
216 * Here we don't handle the case when the BAR is not page
217 * aligned because we can't expect the BAR will be
218 * assigned into the same location in a page in guest
219 * when we passthrough the BAR. And it's hard to access
220 * this BAR in userspace because we have no way to get
221 * the BAR's location in a page.
222 */
223no_mmap:
224 vdev->bar_mmap_supported[bar] = false;
225 }
226}
227
228static void vfio_pci_try_bus_reset(struct vfio_pci_device *vdev);
229static void vfio_pci_disable(struct vfio_pci_device *vdev);
230static int vfio_pci_try_zap_and_vma_lock_cb(struct pci_dev *pdev, void *data);
231
232/*
233 * INTx masking requires the ability to disable INTx signaling via PCI_COMMAND
234 * _and_ the ability detect when the device is asserting INTx via PCI_STATUS.
235 * If a device implements the former but not the latter we would typically
236 * expect broken_intx_masking be set and require an exclusive interrupt.
237 * However since we do have control of the device's ability to assert INTx,
238 * we can instead pretend that the device does not implement INTx, virtualizing
239 * the pin register to report zero and maintaining DisINTx set on the host.
240 */
241static bool vfio_pci_nointx(struct pci_dev *pdev)
242{
243 switch (pdev->vendor) {
244 case PCI_VENDOR_ID_INTEL:
245 switch (pdev->device) {
246 /* All i40e (XL710/X710/XXV710) 10/20/25/40GbE NICs */
247 case 0x1572:
248 case 0x1574:
249 case 0x1580 ... 0x1581:
250 case 0x1583 ... 0x158b:
251 case 0x37d0 ... 0x37d2:
252 /* X550 */
253 case 0x1563:
254 return true;
255 default:
256 return false;
257 }
258 }
259
260 return false;
261}
262
263static void vfio_pci_probe_power_state(struct vfio_pci_device *vdev)
264{
265 struct pci_dev *pdev = vdev->pdev;
266 u16 pmcsr;
267
268 if (!pdev->pm_cap)
269 return;
270
271 pci_read_config_word(pdev, pdev->pm_cap + PCI_PM_CTRL, &pmcsr);
272
273 vdev->needs_pm_restore = !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET);
274}
275
276/*
277 * pci_set_power_state() wrapper handling devices which perform a soft reset on
278 * D3->D0 transition. Save state prior to D0/1/2->D3, stash it on the vdev,
279 * restore when returned to D0. Saved separately from pci_saved_state for use
280 * by PM capability emulation and separately from pci_dev internal saved state
281 * to avoid it being overwritten and consumed around other resets.
282 */
283int vfio_pci_set_power_state(struct vfio_pci_device *vdev, pci_power_t state)
284{
285 struct pci_dev *pdev = vdev->pdev;
286 bool needs_restore = false, needs_save = false;
287 int ret;
288
289 if (vdev->needs_pm_restore) {
290 if (pdev->current_state < PCI_D3hot && state >= PCI_D3hot) {
291 pci_save_state(pdev);
292 needs_save = true;
293 }
294
295 if (pdev->current_state >= PCI_D3hot && state <= PCI_D0)
296 needs_restore = true;
297 }
298
299 ret = pci_set_power_state(pdev, state);
300
301 if (!ret) {
302 /* D3 might be unsupported via quirk, skip unless in D3 */
303 if (needs_save && pdev->current_state >= PCI_D3hot) {
304 vdev->pm_save = pci_store_saved_state(pdev);
305 } else if (needs_restore) {
306 pci_load_and_free_saved_state(pdev, &vdev->pm_save);
307 pci_restore_state(pdev);
308 }
309 }
310
311 return ret;
312}
313
314static int vfio_pci_enable(struct vfio_pci_device *vdev)
315{
316 struct pci_dev *pdev = vdev->pdev;
317 int ret;
318 u16 cmd;
319 u8 msix_pos;
320
321 vfio_pci_set_power_state(vdev, PCI_D0);
322
323 /* Don't allow our initial saved state to include busmaster */
324 pci_clear_master(pdev);
325
326 ret = pci_enable_device(pdev);
327 if (ret)
328 return ret;
329
330 /* If reset fails because of the device lock, fail this path entirely */
331 ret = pci_try_reset_function(pdev);
332 if (ret == -EAGAIN) {
333 pci_disable_device(pdev);
334 return ret;
335 }
336
337 vdev->reset_works = !ret;
338 pci_save_state(pdev);
339 vdev->pci_saved_state = pci_store_saved_state(pdev);
340 if (!vdev->pci_saved_state)
341 pci_dbg(pdev, "%s: Couldn't store saved state\n", __func__);
342
343 if (likely(!nointxmask)) {
344 if (vfio_pci_nointx(pdev)) {
345 pci_info(pdev, "Masking broken INTx support\n");
346 vdev->nointx = true;
347 pci_intx(pdev, 0);
348 } else
349 vdev->pci_2_3 = pci_intx_mask_supported(pdev);
350 }
351
352 pci_read_config_word(pdev, PCI_COMMAND, &cmd);
353 if (vdev->pci_2_3 && (cmd & PCI_COMMAND_INTX_DISABLE)) {
354 cmd &= ~PCI_COMMAND_INTX_DISABLE;
355 pci_write_config_word(pdev, PCI_COMMAND, cmd);
356 }
357
358 ret = vfio_config_init(vdev);
359 if (ret) {
360 kfree(vdev->pci_saved_state);
361 vdev->pci_saved_state = NULL;
362 pci_disable_device(pdev);
363 return ret;
364 }
365
366 msix_pos = pdev->msix_cap;
367 if (msix_pos) {
368 u16 flags;
369 u32 table;
370
371 pci_read_config_word(pdev, msix_pos + PCI_MSIX_FLAGS, &flags);
372 pci_read_config_dword(pdev, msix_pos + PCI_MSIX_TABLE, &table);
373
374 vdev->msix_bar = table & PCI_MSIX_TABLE_BIR;
375 vdev->msix_offset = table & PCI_MSIX_TABLE_OFFSET;
376 vdev->msix_size = ((flags & PCI_MSIX_FLAGS_QSIZE) + 1) * 16;
377 } else
378 vdev->msix_bar = 0xFF;
379
380 if (!vfio_vga_disabled() && vfio_pci_is_vga(pdev))
381 vdev->has_vga = true;
382
383
384 if (vfio_pci_is_vga(pdev) &&
385 pdev->vendor == PCI_VENDOR_ID_INTEL &&
386 IS_ENABLED(CONFIG_VFIO_PCI_IGD)) {
387 ret = vfio_pci_igd_init(vdev);
388 if (ret) {
389 pci_warn(pdev, "Failed to setup Intel IGD regions\n");
390 goto disable_exit;
391 }
392 }
393
394 if (pdev->vendor == PCI_VENDOR_ID_NVIDIA &&
395 IS_ENABLED(CONFIG_VFIO_PCI_NVLINK2)) {
396 ret = vfio_pci_nvdia_v100_nvlink2_init(vdev);
397 if (ret && ret != -ENODEV) {
398 pci_warn(pdev, "Failed to setup NVIDIA NV2 RAM region\n");
399 goto disable_exit;
400 }
401 }
402
403 if (pdev->vendor == PCI_VENDOR_ID_IBM &&
404 IS_ENABLED(CONFIG_VFIO_PCI_NVLINK2)) {
405 ret = vfio_pci_ibm_npu2_init(vdev);
406 if (ret && ret != -ENODEV) {
407 pci_warn(pdev, "Failed to setup NVIDIA NV2 ATSD region\n");
408 goto disable_exit;
409 }
410 }
411
412 vfio_pci_probe_mmaps(vdev);
413
414 return 0;
415
416disable_exit:
417 vfio_pci_disable(vdev);
418 return ret;
419}
420
421static void vfio_pci_disable(struct vfio_pci_device *vdev)
422{
423 struct pci_dev *pdev = vdev->pdev;
424 struct vfio_pci_dummy_resource *dummy_res, *tmp;
425 struct vfio_pci_ioeventfd *ioeventfd, *ioeventfd_tmp;
426 int i, bar;
427
428 /* Stop the device from further DMA */
429 pci_clear_master(pdev);
430
431 vfio_pci_set_irqs_ioctl(vdev, VFIO_IRQ_SET_DATA_NONE |
432 VFIO_IRQ_SET_ACTION_TRIGGER,
433 vdev->irq_type, 0, 0, NULL);
434
435 /* Device closed, don't need mutex here */
436 list_for_each_entry_safe(ioeventfd, ioeventfd_tmp,
437 &vdev->ioeventfds_list, next) {
438 vfio_virqfd_disable(&ioeventfd->virqfd);
439 list_del(&ioeventfd->next);
440 kfree(ioeventfd);
441 }
442 vdev->ioeventfds_nr = 0;
443
444 vdev->virq_disabled = false;
445
446 for (i = 0; i < vdev->num_regions; i++)
447 vdev->region[i].ops->release(vdev, &vdev->region[i]);
448
449 vdev->num_regions = 0;
450 kfree(vdev->region);
451 vdev->region = NULL; /* don't krealloc a freed pointer */
452
453 vfio_config_free(vdev);
454
455 for (i = 0; i < PCI_STD_NUM_BARS; i++) {
456 bar = i + PCI_STD_RESOURCES;
457 if (!vdev->barmap[bar])
458 continue;
459 pci_iounmap(pdev, vdev->barmap[bar]);
460 pci_release_selected_regions(pdev, 1 << bar);
461 vdev->barmap[bar] = NULL;
462 }
463
464 list_for_each_entry_safe(dummy_res, tmp,
465 &vdev->dummy_resources_list, res_next) {
466 list_del(&dummy_res->res_next);
467 release_resource(&dummy_res->resource);
468 kfree(dummy_res);
469 }
470
471 vdev->needs_reset = true;
472
473 /*
474 * If we have saved state, restore it. If we can reset the device,
475 * even better. Resetting with current state seems better than
476 * nothing, but saving and restoring current state without reset
477 * is just busy work.
478 */
479 if (pci_load_and_free_saved_state(pdev, &vdev->pci_saved_state)) {
480 pci_info(pdev, "%s: Couldn't reload saved state\n", __func__);
481
482 if (!vdev->reset_works)
483 goto out;
484
485 pci_save_state(pdev);
486 }
487
488 /*
489 * Disable INTx and MSI, presumably to avoid spurious interrupts
490 * during reset. Stolen from pci_reset_function()
491 */
492 pci_write_config_word(pdev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE);
493
494 /*
495 * Try to get the locks ourselves to prevent a deadlock. The
496 * success of this is dependent on being able to lock the device,
497 * which is not always possible.
498 * We can not use the "try" reset interface here, which will
499 * overwrite the previously restored configuration information.
500 */
501 if (vdev->reset_works && pci_cfg_access_trylock(pdev)) {
502 if (device_trylock(&pdev->dev)) {
503 if (!__pci_reset_function_locked(pdev))
504 vdev->needs_reset = false;
505 device_unlock(&pdev->dev);
506 }
507 pci_cfg_access_unlock(pdev);
508 }
509
510 pci_restore_state(pdev);
511out:
512 pci_disable_device(pdev);
513
514 vfio_pci_try_bus_reset(vdev);
515
516 if (!disable_idle_d3)
517 vfio_pci_set_power_state(vdev, PCI_D3hot);
518}
519
520static struct pci_driver vfio_pci_driver;
521
522static struct vfio_pci_device *get_pf_vdev(struct vfio_pci_device *vdev,
523 struct vfio_device **pf_dev)
524{
525 struct pci_dev *physfn = pci_physfn(vdev->pdev);
526
527 if (!vdev->pdev->is_virtfn)
528 return NULL;
529
530 *pf_dev = vfio_device_get_from_dev(&physfn->dev);
531 if (!*pf_dev)
532 return NULL;
533
534 if (pci_dev_driver(physfn) != &vfio_pci_driver) {
535 vfio_device_put(*pf_dev);
536 return NULL;
537 }
538
539 return vfio_device_data(*pf_dev);
540}
541
542static void vfio_pci_vf_token_user_add(struct vfio_pci_device *vdev, int val)
543{
544 struct vfio_device *pf_dev;
545 struct vfio_pci_device *pf_vdev = get_pf_vdev(vdev, &pf_dev);
546
547 if (!pf_vdev)
548 return;
549
550 mutex_lock(&pf_vdev->vf_token->lock);
551 pf_vdev->vf_token->users += val;
552 WARN_ON(pf_vdev->vf_token->users < 0);
553 mutex_unlock(&pf_vdev->vf_token->lock);
554
555 vfio_device_put(pf_dev);
556}
557
558static void vfio_pci_release(void *device_data)
559{
560 struct vfio_pci_device *vdev = device_data;
561
562 mutex_lock(&vdev->reflck->lock);
563
564 if (!(--vdev->refcnt)) {
565 vfio_pci_vf_token_user_add(vdev, -1);
566 vfio_spapr_pci_eeh_release(vdev->pdev);
567 vfio_pci_disable(vdev);
568
569 mutex_lock(&vdev->igate);
570 if (vdev->err_trigger) {
571 eventfd_ctx_put(vdev->err_trigger);
572 vdev->err_trigger = NULL;
573 }
574 if (vdev->req_trigger) {
575 eventfd_ctx_put(vdev->req_trigger);
576 vdev->req_trigger = NULL;
577 }
578 mutex_unlock(&vdev->igate);
579 }
580
581 mutex_unlock(&vdev->reflck->lock);
582
583 module_put(THIS_MODULE);
584}
585
586static int vfio_pci_open(void *device_data)
587{
588 struct vfio_pci_device *vdev = device_data;
589 int ret = 0;
590
591 if (!try_module_get(THIS_MODULE))
592 return -ENODEV;
593
594 mutex_lock(&vdev->reflck->lock);
595
596 if (!vdev->refcnt) {
597 ret = vfio_pci_enable(vdev);
598 if (ret)
599 goto error;
600
601 vfio_spapr_pci_eeh_open(vdev->pdev);
602 vfio_pci_vf_token_user_add(vdev, 1);
603 }
604 vdev->refcnt++;
605error:
606 mutex_unlock(&vdev->reflck->lock);
607 if (ret)
608 module_put(THIS_MODULE);
609 return ret;
610}
611
612static int vfio_pci_get_irq_count(struct vfio_pci_device *vdev, int irq_type)
613{
614 if (irq_type == VFIO_PCI_INTX_IRQ_INDEX) {
615 u8 pin;
616
617 if (!IS_ENABLED(CONFIG_VFIO_PCI_INTX) ||
618 vdev->nointx || vdev->pdev->is_virtfn)
619 return 0;
620
621 pci_read_config_byte(vdev->pdev, PCI_INTERRUPT_PIN, &pin);
622
623 return pin ? 1 : 0;
624 } else if (irq_type == VFIO_PCI_MSI_IRQ_INDEX) {
625 u8 pos;
626 u16 flags;
627
628 pos = vdev->pdev->msi_cap;
629 if (pos) {
630 pci_read_config_word(vdev->pdev,
631 pos + PCI_MSI_FLAGS, &flags);
632 return 1 << ((flags & PCI_MSI_FLAGS_QMASK) >> 1);
633 }
634 } else if (irq_type == VFIO_PCI_MSIX_IRQ_INDEX) {
635 u8 pos;
636 u16 flags;
637
638 pos = vdev->pdev->msix_cap;
639 if (pos) {
640 pci_read_config_word(vdev->pdev,
641 pos + PCI_MSIX_FLAGS, &flags);
642
643 return (flags & PCI_MSIX_FLAGS_QSIZE) + 1;
644 }
645 } else if (irq_type == VFIO_PCI_ERR_IRQ_INDEX) {
646 if (pci_is_pcie(vdev->pdev))
647 return 1;
648 } else if (irq_type == VFIO_PCI_REQ_IRQ_INDEX) {
649 return 1;
650 }
651
652 return 0;
653}
654
655static int vfio_pci_count_devs(struct pci_dev *pdev, void *data)
656{
657 (*(int *)data)++;
658 return 0;
659}
660
661struct vfio_pci_fill_info {
662 int max;
663 int cur;
664 struct vfio_pci_dependent_device *devices;
665};
666
667static int vfio_pci_fill_devs(struct pci_dev *pdev, void *data)
668{
669 struct vfio_pci_fill_info *fill = data;
670 struct iommu_group *iommu_group;
671
672 if (fill->cur == fill->max)
673 return -EAGAIN; /* Something changed, try again */
674
675 iommu_group = iommu_group_get(&pdev->dev);
676 if (!iommu_group)
677 return -EPERM; /* Cannot reset non-isolated devices */
678
679 fill->devices[fill->cur].group_id = iommu_group_id(iommu_group);
680 fill->devices[fill->cur].segment = pci_domain_nr(pdev->bus);
681 fill->devices[fill->cur].bus = pdev->bus->number;
682 fill->devices[fill->cur].devfn = pdev->devfn;
683 fill->cur++;
684 iommu_group_put(iommu_group);
685 return 0;
686}
687
688struct vfio_pci_group_entry {
689 struct vfio_group *group;
690 int id;
691};
692
693struct vfio_pci_group_info {
694 int count;
695 struct vfio_pci_group_entry *groups;
696};
697
698static int vfio_pci_validate_devs(struct pci_dev *pdev, void *data)
699{
700 struct vfio_pci_group_info *info = data;
701 struct iommu_group *group;
702 int id, i;
703
704 group = iommu_group_get(&pdev->dev);
705 if (!group)
706 return -EPERM;
707
708 id = iommu_group_id(group);
709
710 for (i = 0; i < info->count; i++)
711 if (info->groups[i].id == id)
712 break;
713
714 iommu_group_put(group);
715
716 return (i == info->count) ? -EINVAL : 0;
717}
718
719static bool vfio_pci_dev_below_slot(struct pci_dev *pdev, struct pci_slot *slot)
720{
721 for (; pdev; pdev = pdev->bus->self)
722 if (pdev->bus == slot->bus)
723 return (pdev->slot == slot);
724 return false;
725}
726
727struct vfio_pci_walk_info {
728 int (*fn)(struct pci_dev *, void *data);
729 void *data;
730 struct pci_dev *pdev;
731 bool slot;
732 int ret;
733};
734
735static int vfio_pci_walk_wrapper(struct pci_dev *pdev, void *data)
736{
737 struct vfio_pci_walk_info *walk = data;
738
739 if (!walk->slot || vfio_pci_dev_below_slot(pdev, walk->pdev->slot))
740 walk->ret = walk->fn(pdev, walk->data);
741
742 return walk->ret;
743}
744
745static int vfio_pci_for_each_slot_or_bus(struct pci_dev *pdev,
746 int (*fn)(struct pci_dev *,
747 void *data), void *data,
748 bool slot)
749{
750 struct vfio_pci_walk_info walk = {
751 .fn = fn, .data = data, .pdev = pdev, .slot = slot, .ret = 0,
752 };
753
754 pci_walk_bus(pdev->bus, vfio_pci_walk_wrapper, &walk);
755
756 return walk.ret;
757}
758
759static int msix_mmappable_cap(struct vfio_pci_device *vdev,
760 struct vfio_info_cap *caps)
761{
762 struct vfio_info_cap_header header = {
763 .id = VFIO_REGION_INFO_CAP_MSIX_MAPPABLE,
764 .version = 1
765 };
766
767 return vfio_info_add_capability(caps, &header, sizeof(header));
768}
769
770int vfio_pci_register_dev_region(struct vfio_pci_device *vdev,
771 unsigned int type, unsigned int subtype,
772 const struct vfio_pci_regops *ops,
773 size_t size, u32 flags, void *data)
774{
775 struct vfio_pci_region *region;
776
777 region = krealloc(vdev->region,
778 (vdev->num_regions + 1) * sizeof(*region),
779 GFP_KERNEL);
780 if (!region)
781 return -ENOMEM;
782
783 vdev->region = region;
784 vdev->region[vdev->num_regions].type = type;
785 vdev->region[vdev->num_regions].subtype = subtype;
786 vdev->region[vdev->num_regions].ops = ops;
787 vdev->region[vdev->num_regions].size = size;
788 vdev->region[vdev->num_regions].flags = flags;
789 vdev->region[vdev->num_regions].data = data;
790
791 vdev->num_regions++;
792
793 return 0;
794}
795
796struct vfio_devices {
797 struct vfio_device **devices;
798 int cur_index;
799 int max_index;
800};
801
802static long vfio_pci_ioctl(void *device_data,
803 unsigned int cmd, unsigned long arg)
804{
805 struct vfio_pci_device *vdev = device_data;
806 unsigned long minsz;
807
808 if (cmd == VFIO_DEVICE_GET_INFO) {
809 struct vfio_device_info info;
810
811 minsz = offsetofend(struct vfio_device_info, num_irqs);
812
813 if (copy_from_user(&info, (void __user *)arg, minsz))
814 return -EFAULT;
815
816 if (info.argsz < minsz)
817 return -EINVAL;
818
819 info.flags = VFIO_DEVICE_FLAGS_PCI;
820
821 if (vdev->reset_works)
822 info.flags |= VFIO_DEVICE_FLAGS_RESET;
823
824 info.num_regions = VFIO_PCI_NUM_REGIONS + vdev->num_regions;
825 info.num_irqs = VFIO_PCI_NUM_IRQS;
826
827 return copy_to_user((void __user *)arg, &info, minsz) ?
828 -EFAULT : 0;
829
830 } else if (cmd == VFIO_DEVICE_GET_REGION_INFO) {
831 struct pci_dev *pdev = vdev->pdev;
832 struct vfio_region_info info;
833 struct vfio_info_cap caps = { .buf = NULL, .size = 0 };
834 int i, ret;
835
836 minsz = offsetofend(struct vfio_region_info, offset);
837
838 if (copy_from_user(&info, (void __user *)arg, minsz))
839 return -EFAULT;
840
841 if (info.argsz < minsz)
842 return -EINVAL;
843
844 switch (info.index) {
845 case VFIO_PCI_CONFIG_REGION_INDEX:
846 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
847 info.size = pdev->cfg_size;
848 info.flags = VFIO_REGION_INFO_FLAG_READ |
849 VFIO_REGION_INFO_FLAG_WRITE;
850 break;
851 case VFIO_PCI_BAR0_REGION_INDEX ... VFIO_PCI_BAR5_REGION_INDEX:
852 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
853 info.size = pci_resource_len(pdev, info.index);
854 if (!info.size) {
855 info.flags = 0;
856 break;
857 }
858
859 info.flags = VFIO_REGION_INFO_FLAG_READ |
860 VFIO_REGION_INFO_FLAG_WRITE;
861 if (vdev->bar_mmap_supported[info.index]) {
862 info.flags |= VFIO_REGION_INFO_FLAG_MMAP;
863 if (info.index == vdev->msix_bar) {
864 ret = msix_mmappable_cap(vdev, &caps);
865 if (ret)
866 return ret;
867 }
868 }
869
870 break;
871 case VFIO_PCI_ROM_REGION_INDEX:
872 {
873 void __iomem *io;
874 size_t size;
875 u16 cmd;
876
877 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
878 info.flags = 0;
879
880 /* Report the BAR size, not the ROM size */
881 info.size = pci_resource_len(pdev, info.index);
882 if (!info.size) {
883 /* Shadow ROMs appear as PCI option ROMs */
884 if (pdev->resource[PCI_ROM_RESOURCE].flags &
885 IORESOURCE_ROM_SHADOW)
886 info.size = 0x20000;
887 else
888 break;
889 }
890
891 /*
892 * Is it really there? Enable memory decode for
893 * implicit access in pci_map_rom().
894 */
895 cmd = vfio_pci_memory_lock_and_enable(vdev);
896 io = pci_map_rom(pdev, &size);
897 if (io) {
898 info.flags = VFIO_REGION_INFO_FLAG_READ;
899 pci_unmap_rom(pdev, io);
900 } else {
901 info.size = 0;
902 }
903 vfio_pci_memory_unlock_and_restore(vdev, cmd);
904
905 break;
906 }
907 case VFIO_PCI_VGA_REGION_INDEX:
908 if (!vdev->has_vga)
909 return -EINVAL;
910
911 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
912 info.size = 0xc0000;
913 info.flags = VFIO_REGION_INFO_FLAG_READ |
914 VFIO_REGION_INFO_FLAG_WRITE;
915
916 break;
917 default:
918 {
919 struct vfio_region_info_cap_type cap_type = {
920 .header.id = VFIO_REGION_INFO_CAP_TYPE,
921 .header.version = 1 };
922
923 if (info.index >=
924 VFIO_PCI_NUM_REGIONS + vdev->num_regions)
925 return -EINVAL;
926 info.index = array_index_nospec(info.index,
927 VFIO_PCI_NUM_REGIONS +
928 vdev->num_regions);
929
930 i = info.index - VFIO_PCI_NUM_REGIONS;
931
932 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
933 info.size = vdev->region[i].size;
934 info.flags = vdev->region[i].flags;
935
936 cap_type.type = vdev->region[i].type;
937 cap_type.subtype = vdev->region[i].subtype;
938
939 ret = vfio_info_add_capability(&caps, &cap_type.header,
940 sizeof(cap_type));
941 if (ret)
942 return ret;
943
944 if (vdev->region[i].ops->add_capability) {
945 ret = vdev->region[i].ops->add_capability(vdev,
946 &vdev->region[i], &caps);
947 if (ret)
948 return ret;
949 }
950 }
951 }
952
953 if (caps.size) {
954 info.flags |= VFIO_REGION_INFO_FLAG_CAPS;
955 if (info.argsz < sizeof(info) + caps.size) {
956 info.argsz = sizeof(info) + caps.size;
957 info.cap_offset = 0;
958 } else {
959 vfio_info_cap_shift(&caps, sizeof(info));
960 if (copy_to_user((void __user *)arg +
961 sizeof(info), caps.buf,
962 caps.size)) {
963 kfree(caps.buf);
964 return -EFAULT;
965 }
966 info.cap_offset = sizeof(info);
967 }
968
969 kfree(caps.buf);
970 }
971
972 return copy_to_user((void __user *)arg, &info, minsz) ?
973 -EFAULT : 0;
974
975 } else if (cmd == VFIO_DEVICE_GET_IRQ_INFO) {
976 struct vfio_irq_info info;
977
978 minsz = offsetofend(struct vfio_irq_info, count);
979
980 if (copy_from_user(&info, (void __user *)arg, minsz))
981 return -EFAULT;
982
983 if (info.argsz < minsz || info.index >= VFIO_PCI_NUM_IRQS)
984 return -EINVAL;
985
986 switch (info.index) {
987 case VFIO_PCI_INTX_IRQ_INDEX ... VFIO_PCI_MSIX_IRQ_INDEX:
988 case VFIO_PCI_REQ_IRQ_INDEX:
989 break;
990 case VFIO_PCI_ERR_IRQ_INDEX:
991 if (pci_is_pcie(vdev->pdev))
992 break;
993 fallthrough;
994 default:
995 return -EINVAL;
996 }
997
998 info.flags = VFIO_IRQ_INFO_EVENTFD;
999
1000 info.count = vfio_pci_get_irq_count(vdev, info.index);
1001
1002 if (info.index == VFIO_PCI_INTX_IRQ_INDEX)
1003 info.flags |= (VFIO_IRQ_INFO_MASKABLE |
1004 VFIO_IRQ_INFO_AUTOMASKED);
1005 else
1006 info.flags |= VFIO_IRQ_INFO_NORESIZE;
1007
1008 return copy_to_user((void __user *)arg, &info, minsz) ?
1009 -EFAULT : 0;
1010
1011 } else if (cmd == VFIO_DEVICE_SET_IRQS) {
1012 struct vfio_irq_set hdr;
1013 u8 *data = NULL;
1014 int max, ret = 0;
1015 size_t data_size = 0;
1016
1017 minsz = offsetofend(struct vfio_irq_set, count);
1018
1019 if (copy_from_user(&hdr, (void __user *)arg, minsz))
1020 return -EFAULT;
1021
1022 max = vfio_pci_get_irq_count(vdev, hdr.index);
1023
1024 ret = vfio_set_irqs_validate_and_prepare(&hdr, max,
1025 VFIO_PCI_NUM_IRQS, &data_size);
1026 if (ret)
1027 return ret;
1028
1029 if (data_size) {
1030 data = memdup_user((void __user *)(arg + minsz),
1031 data_size);
1032 if (IS_ERR(data))
1033 return PTR_ERR(data);
1034 }
1035
1036 mutex_lock(&vdev->igate);
1037
1038 ret = vfio_pci_set_irqs_ioctl(vdev, hdr.flags, hdr.index,
1039 hdr.start, hdr.count, data);
1040
1041 mutex_unlock(&vdev->igate);
1042 kfree(data);
1043
1044 return ret;
1045
1046 } else if (cmd == VFIO_DEVICE_RESET) {
1047 int ret;
1048
1049 if (!vdev->reset_works)
1050 return -EINVAL;
1051
1052 vfio_pci_zap_and_down_write_memory_lock(vdev);
1053 ret = pci_try_reset_function(vdev->pdev);
1054 up_write(&vdev->memory_lock);
1055
1056 return ret;
1057
1058 } else if (cmd == VFIO_DEVICE_GET_PCI_HOT_RESET_INFO) {
1059 struct vfio_pci_hot_reset_info hdr;
1060 struct vfio_pci_fill_info fill = { 0 };
1061 struct vfio_pci_dependent_device *devices = NULL;
1062 bool slot = false;
1063 int ret = 0;
1064
1065 minsz = offsetofend(struct vfio_pci_hot_reset_info, count);
1066
1067 if (copy_from_user(&hdr, (void __user *)arg, minsz))
1068 return -EFAULT;
1069
1070 if (hdr.argsz < minsz)
1071 return -EINVAL;
1072
1073 hdr.flags = 0;
1074
1075 /* Can we do a slot or bus reset or neither? */
1076 if (!pci_probe_reset_slot(vdev->pdev->slot))
1077 slot = true;
1078 else if (pci_probe_reset_bus(vdev->pdev->bus))
1079 return -ENODEV;
1080
1081 /* How many devices are affected? */
1082 ret = vfio_pci_for_each_slot_or_bus(vdev->pdev,
1083 vfio_pci_count_devs,
1084 &fill.max, slot);
1085 if (ret)
1086 return ret;
1087
1088 WARN_ON(!fill.max); /* Should always be at least one */
1089
1090 /*
1091 * If there's enough space, fill it now, otherwise return
1092 * -ENOSPC and the number of devices affected.
1093 */
1094 if (hdr.argsz < sizeof(hdr) + (fill.max * sizeof(*devices))) {
1095 ret = -ENOSPC;
1096 hdr.count = fill.max;
1097 goto reset_info_exit;
1098 }
1099
1100 devices = kcalloc(fill.max, sizeof(*devices), GFP_KERNEL);
1101 if (!devices)
1102 return -ENOMEM;
1103
1104 fill.devices = devices;
1105
1106 ret = vfio_pci_for_each_slot_or_bus(vdev->pdev,
1107 vfio_pci_fill_devs,
1108 &fill, slot);
1109
1110 /*
1111 * If a device was removed between counting and filling,
1112 * we may come up short of fill.max. If a device was
1113 * added, we'll have a return of -EAGAIN above.
1114 */
1115 if (!ret)
1116 hdr.count = fill.cur;
1117
1118reset_info_exit:
1119 if (copy_to_user((void __user *)arg, &hdr, minsz))
1120 ret = -EFAULT;
1121
1122 if (!ret) {
1123 if (copy_to_user((void __user *)(arg + minsz), devices,
1124 hdr.count * sizeof(*devices)))
1125 ret = -EFAULT;
1126 }
1127
1128 kfree(devices);
1129 return ret;
1130
1131 } else if (cmd == VFIO_DEVICE_PCI_HOT_RESET) {
1132 struct vfio_pci_hot_reset hdr;
1133 int32_t *group_fds;
1134 struct vfio_pci_group_entry *groups;
1135 struct vfio_pci_group_info info;
1136 struct vfio_devices devs = { .cur_index = 0 };
1137 bool slot = false;
1138 int i, group_idx, mem_idx = 0, count = 0, ret = 0;
1139
1140 minsz = offsetofend(struct vfio_pci_hot_reset, count);
1141
1142 if (copy_from_user(&hdr, (void __user *)arg, minsz))
1143 return -EFAULT;
1144
1145 if (hdr.argsz < minsz || hdr.flags)
1146 return -EINVAL;
1147
1148 /* Can we do a slot or bus reset or neither? */
1149 if (!pci_probe_reset_slot(vdev->pdev->slot))
1150 slot = true;
1151 else if (pci_probe_reset_bus(vdev->pdev->bus))
1152 return -ENODEV;
1153
1154 /*
1155 * We can't let userspace give us an arbitrarily large
1156 * buffer to copy, so verify how many we think there
1157 * could be. Note groups can have multiple devices so
1158 * one group per device is the max.
1159 */
1160 ret = vfio_pci_for_each_slot_or_bus(vdev->pdev,
1161 vfio_pci_count_devs,
1162 &count, slot);
1163 if (ret)
1164 return ret;
1165
1166 /* Somewhere between 1 and count is OK */
1167 if (!hdr.count || hdr.count > count)
1168 return -EINVAL;
1169
1170 group_fds = kcalloc(hdr.count, sizeof(*group_fds), GFP_KERNEL);
1171 groups = kcalloc(hdr.count, sizeof(*groups), GFP_KERNEL);
1172 if (!group_fds || !groups) {
1173 kfree(group_fds);
1174 kfree(groups);
1175 return -ENOMEM;
1176 }
1177
1178 if (copy_from_user(group_fds, (void __user *)(arg + minsz),
1179 hdr.count * sizeof(*group_fds))) {
1180 kfree(group_fds);
1181 kfree(groups);
1182 return -EFAULT;
1183 }
1184
1185 /*
1186 * For each group_fd, get the group through the vfio external
1187 * user interface and store the group and iommu ID. This
1188 * ensures the group is held across the reset.
1189 */
1190 for (group_idx = 0; group_idx < hdr.count; group_idx++) {
1191 struct vfio_group *group;
1192 struct fd f = fdget(group_fds[group_idx]);
1193 if (!f.file) {
1194 ret = -EBADF;
1195 break;
1196 }
1197
1198 group = vfio_group_get_external_user(f.file);
1199 fdput(f);
1200 if (IS_ERR(group)) {
1201 ret = PTR_ERR(group);
1202 break;
1203 }
1204
1205 groups[group_idx].group = group;
1206 groups[group_idx].id =
1207 vfio_external_user_iommu_id(group);
1208 }
1209
1210 kfree(group_fds);
1211
1212 /* release reference to groups on error */
1213 if (ret)
1214 goto hot_reset_release;
1215
1216 info.count = hdr.count;
1217 info.groups = groups;
1218
1219 /*
1220 * Test whether all the affected devices are contained
1221 * by the set of groups provided by the user.
1222 */
1223 ret = vfio_pci_for_each_slot_or_bus(vdev->pdev,
1224 vfio_pci_validate_devs,
1225 &info, slot);
1226 if (ret)
1227 goto hot_reset_release;
1228
1229 devs.max_index = count;
1230 devs.devices = kcalloc(count, sizeof(struct vfio_device *),
1231 GFP_KERNEL);
1232 if (!devs.devices) {
1233 ret = -ENOMEM;
1234 goto hot_reset_release;
1235 }
1236
1237 /*
1238 * We need to get memory_lock for each device, but devices
1239 * can share mmap_lock, therefore we need to zap and hold
1240 * the vma_lock for each device, and only then get each
1241 * memory_lock.
1242 */
1243 ret = vfio_pci_for_each_slot_or_bus(vdev->pdev,
1244 vfio_pci_try_zap_and_vma_lock_cb,
1245 &devs, slot);
1246 if (ret)
1247 goto hot_reset_release;
1248
1249 for (; mem_idx < devs.cur_index; mem_idx++) {
1250 struct vfio_pci_device *tmp;
1251
1252 tmp = vfio_device_data(devs.devices[mem_idx]);
1253
1254 ret = down_write_trylock(&tmp->memory_lock);
1255 if (!ret) {
1256 ret = -EBUSY;
1257 goto hot_reset_release;
1258 }
1259 mutex_unlock(&tmp->vma_lock);
1260 }
1261
1262 /* User has access, do the reset */
1263 ret = pci_reset_bus(vdev->pdev);
1264
1265hot_reset_release:
1266 for (i = 0; i < devs.cur_index; i++) {
1267 struct vfio_device *device;
1268 struct vfio_pci_device *tmp;
1269
1270 device = devs.devices[i];
1271 tmp = vfio_device_data(device);
1272
1273 if (i < mem_idx)
1274 up_write(&tmp->memory_lock);
1275 else
1276 mutex_unlock(&tmp->vma_lock);
1277 vfio_device_put(device);
1278 }
1279 kfree(devs.devices);
1280
1281 for (group_idx--; group_idx >= 0; group_idx--)
1282 vfio_group_put_external_user(groups[group_idx].group);
1283
1284 kfree(groups);
1285 return ret;
1286 } else if (cmd == VFIO_DEVICE_IOEVENTFD) {
1287 struct vfio_device_ioeventfd ioeventfd;
1288 int count;
1289
1290 minsz = offsetofend(struct vfio_device_ioeventfd, fd);
1291
1292 if (copy_from_user(&ioeventfd, (void __user *)arg, minsz))
1293 return -EFAULT;
1294
1295 if (ioeventfd.argsz < minsz)
1296 return -EINVAL;
1297
1298 if (ioeventfd.flags & ~VFIO_DEVICE_IOEVENTFD_SIZE_MASK)
1299 return -EINVAL;
1300
1301 count = ioeventfd.flags & VFIO_DEVICE_IOEVENTFD_SIZE_MASK;
1302
1303 if (hweight8(count) != 1 || ioeventfd.fd < -1)
1304 return -EINVAL;
1305
1306 return vfio_pci_ioeventfd(vdev, ioeventfd.offset,
1307 ioeventfd.data, count, ioeventfd.fd);
1308 } else if (cmd == VFIO_DEVICE_FEATURE) {
1309 struct vfio_device_feature feature;
1310 uuid_t uuid;
1311
1312 minsz = offsetofend(struct vfio_device_feature, flags);
1313
1314 if (copy_from_user(&feature, (void __user *)arg, minsz))
1315 return -EFAULT;
1316
1317 if (feature.argsz < minsz)
1318 return -EINVAL;
1319
1320 /* Check unknown flags */
1321 if (feature.flags & ~(VFIO_DEVICE_FEATURE_MASK |
1322 VFIO_DEVICE_FEATURE_SET |
1323 VFIO_DEVICE_FEATURE_GET |
1324 VFIO_DEVICE_FEATURE_PROBE))
1325 return -EINVAL;
1326
1327 /* GET & SET are mutually exclusive except with PROBE */
1328 if (!(feature.flags & VFIO_DEVICE_FEATURE_PROBE) &&
1329 (feature.flags & VFIO_DEVICE_FEATURE_SET) &&
1330 (feature.flags & VFIO_DEVICE_FEATURE_GET))
1331 return -EINVAL;
1332
1333 switch (feature.flags & VFIO_DEVICE_FEATURE_MASK) {
1334 case VFIO_DEVICE_FEATURE_PCI_VF_TOKEN:
1335 if (!vdev->vf_token)
1336 return -ENOTTY;
1337
1338 /*
1339 * We do not support GET of the VF Token UUID as this
1340 * could expose the token of the previous device user.
1341 */
1342 if (feature.flags & VFIO_DEVICE_FEATURE_GET)
1343 return -EINVAL;
1344
1345 if (feature.flags & VFIO_DEVICE_FEATURE_PROBE)
1346 return 0;
1347
1348 /* Don't SET unless told to do so */
1349 if (!(feature.flags & VFIO_DEVICE_FEATURE_SET))
1350 return -EINVAL;
1351
1352 if (feature.argsz < minsz + sizeof(uuid))
1353 return -EINVAL;
1354
1355 if (copy_from_user(&uuid, (void __user *)(arg + minsz),
1356 sizeof(uuid)))
1357 return -EFAULT;
1358
1359 mutex_lock(&vdev->vf_token->lock);
1360 uuid_copy(&vdev->vf_token->uuid, &uuid);
1361 mutex_unlock(&vdev->vf_token->lock);
1362
1363 return 0;
1364 default:
1365 return -ENOTTY;
1366 }
1367 }
1368
1369 return -ENOTTY;
1370}
1371
1372static ssize_t vfio_pci_rw(void *device_data, char __user *buf,
1373 size_t count, loff_t *ppos, bool iswrite)
1374{
1375 unsigned int index = VFIO_PCI_OFFSET_TO_INDEX(*ppos);
1376 struct vfio_pci_device *vdev = device_data;
1377
1378 if (index >= VFIO_PCI_NUM_REGIONS + vdev->num_regions)
1379 return -EINVAL;
1380
1381 switch (index) {
1382 case VFIO_PCI_CONFIG_REGION_INDEX:
1383 return vfio_pci_config_rw(vdev, buf, count, ppos, iswrite);
1384
1385 case VFIO_PCI_ROM_REGION_INDEX:
1386 if (iswrite)
1387 return -EINVAL;
1388 return vfio_pci_bar_rw(vdev, buf, count, ppos, false);
1389
1390 case VFIO_PCI_BAR0_REGION_INDEX ... VFIO_PCI_BAR5_REGION_INDEX:
1391 return vfio_pci_bar_rw(vdev, buf, count, ppos, iswrite);
1392
1393 case VFIO_PCI_VGA_REGION_INDEX:
1394 return vfio_pci_vga_rw(vdev, buf, count, ppos, iswrite);
1395 default:
1396 index -= VFIO_PCI_NUM_REGIONS;
1397 return vdev->region[index].ops->rw(vdev, buf,
1398 count, ppos, iswrite);
1399 }
1400
1401 return -EINVAL;
1402}
1403
1404static ssize_t vfio_pci_read(void *device_data, char __user *buf,
1405 size_t count, loff_t *ppos)
1406{
1407 if (!count)
1408 return 0;
1409
1410 return vfio_pci_rw(device_data, buf, count, ppos, false);
1411}
1412
1413static ssize_t vfio_pci_write(void *device_data, const char __user *buf,
1414 size_t count, loff_t *ppos)
1415{
1416 if (!count)
1417 return 0;
1418
1419 return vfio_pci_rw(device_data, (char __user *)buf, count, ppos, true);
1420}
1421
1422/* Return 1 on zap and vma_lock acquired, 0 on contention (only with @try) */
1423static int vfio_pci_zap_and_vma_lock(struct vfio_pci_device *vdev, bool try)
1424{
1425 struct vfio_pci_mmap_vma *mmap_vma, *tmp;
1426
1427 /*
1428 * Lock ordering:
1429 * vma_lock is nested under mmap_lock for vm_ops callback paths.
1430 * The memory_lock semaphore is used by both code paths calling
1431 * into this function to zap vmas and the vm_ops.fault callback
1432 * to protect the memory enable state of the device.
1433 *
1434 * When zapping vmas we need to maintain the mmap_lock => vma_lock
1435 * ordering, which requires using vma_lock to walk vma_list to
1436 * acquire an mm, then dropping vma_lock to get the mmap_lock and
1437 * reacquiring vma_lock. This logic is derived from similar
1438 * requirements in uverbs_user_mmap_disassociate().
1439 *
1440 * mmap_lock must always be the top-level lock when it is taken.
1441 * Therefore we can only hold the memory_lock write lock when
1442 * vma_list is empty, as we'd need to take mmap_lock to clear
1443 * entries. vma_list can only be guaranteed empty when holding
1444 * vma_lock, thus memory_lock is nested under vma_lock.
1445 *
1446 * This enables the vm_ops.fault callback to acquire vma_lock,
1447 * followed by memory_lock read lock, while already holding
1448 * mmap_lock without risk of deadlock.
1449 */
1450 while (1) {
1451 struct mm_struct *mm = NULL;
1452
1453 if (try) {
1454 if (!mutex_trylock(&vdev->vma_lock))
1455 return 0;
1456 } else {
1457 mutex_lock(&vdev->vma_lock);
1458 }
1459 while (!list_empty(&vdev->vma_list)) {
1460 mmap_vma = list_first_entry(&vdev->vma_list,
1461 struct vfio_pci_mmap_vma,
1462 vma_next);
1463 mm = mmap_vma->vma->vm_mm;
1464 if (mmget_not_zero(mm))
1465 break;
1466
1467 list_del(&mmap_vma->vma_next);
1468 kfree(mmap_vma);
1469 mm = NULL;
1470 }
1471 if (!mm)
1472 return 1;
1473 mutex_unlock(&vdev->vma_lock);
1474
1475 if (try) {
1476 if (!mmap_read_trylock(mm)) {
1477 mmput(mm);
1478 return 0;
1479 }
1480 } else {
1481 mmap_read_lock(mm);
1482 }
1483 if (mmget_still_valid(mm)) {
1484 if (try) {
1485 if (!mutex_trylock(&vdev->vma_lock)) {
1486 mmap_read_unlock(mm);
1487 mmput(mm);
1488 return 0;
1489 }
1490 } else {
1491 mutex_lock(&vdev->vma_lock);
1492 }
1493 list_for_each_entry_safe(mmap_vma, tmp,
1494 &vdev->vma_list, vma_next) {
1495 struct vm_area_struct *vma = mmap_vma->vma;
1496
1497 if (vma->vm_mm != mm)
1498 continue;
1499
1500 list_del(&mmap_vma->vma_next);
1501 kfree(mmap_vma);
1502
1503 zap_vma_ptes(vma, vma->vm_start,
1504 vma->vm_end - vma->vm_start);
1505 }
1506 mutex_unlock(&vdev->vma_lock);
1507 }
1508 mmap_read_unlock(mm);
1509 mmput(mm);
1510 }
1511}
1512
1513void vfio_pci_zap_and_down_write_memory_lock(struct vfio_pci_device *vdev)
1514{
1515 vfio_pci_zap_and_vma_lock(vdev, false);
1516 down_write(&vdev->memory_lock);
1517 mutex_unlock(&vdev->vma_lock);
1518}
1519
1520u16 vfio_pci_memory_lock_and_enable(struct vfio_pci_device *vdev)
1521{
1522 u16 cmd;
1523
1524 down_write(&vdev->memory_lock);
1525 pci_read_config_word(vdev->pdev, PCI_COMMAND, &cmd);
1526 if (!(cmd & PCI_COMMAND_MEMORY))
1527 pci_write_config_word(vdev->pdev, PCI_COMMAND,
1528 cmd | PCI_COMMAND_MEMORY);
1529
1530 return cmd;
1531}
1532
1533void vfio_pci_memory_unlock_and_restore(struct vfio_pci_device *vdev, u16 cmd)
1534{
1535 pci_write_config_word(vdev->pdev, PCI_COMMAND, cmd);
1536 up_write(&vdev->memory_lock);
1537}
1538
1539/* Caller holds vma_lock */
1540static int __vfio_pci_add_vma(struct vfio_pci_device *vdev,
1541 struct vm_area_struct *vma)
1542{
1543 struct vfio_pci_mmap_vma *mmap_vma;
1544
1545 mmap_vma = kmalloc(sizeof(*mmap_vma), GFP_KERNEL);
1546 if (!mmap_vma)
1547 return -ENOMEM;
1548
1549 mmap_vma->vma = vma;
1550 list_add(&mmap_vma->vma_next, &vdev->vma_list);
1551
1552 return 0;
1553}
1554
1555/*
1556 * Zap mmaps on open so that we can fault them in on access and therefore
1557 * our vma_list only tracks mappings accessed since last zap.
1558 */
1559static void vfio_pci_mmap_open(struct vm_area_struct *vma)
1560{
1561 zap_vma_ptes(vma, vma->vm_start, vma->vm_end - vma->vm_start);
1562}
1563
1564static void vfio_pci_mmap_close(struct vm_area_struct *vma)
1565{
1566 struct vfio_pci_device *vdev = vma->vm_private_data;
1567 struct vfio_pci_mmap_vma *mmap_vma;
1568
1569 mutex_lock(&vdev->vma_lock);
1570 list_for_each_entry(mmap_vma, &vdev->vma_list, vma_next) {
1571 if (mmap_vma->vma == vma) {
1572 list_del(&mmap_vma->vma_next);
1573 kfree(mmap_vma);
1574 break;
1575 }
1576 }
1577 mutex_unlock(&vdev->vma_lock);
1578}
1579
1580static vm_fault_t vfio_pci_mmap_fault(struct vm_fault *vmf)
1581{
1582 struct vm_area_struct *vma = vmf->vma;
1583 struct vfio_pci_device *vdev = vma->vm_private_data;
1584 vm_fault_t ret = VM_FAULT_NOPAGE;
1585
1586 mutex_lock(&vdev->vma_lock);
1587 down_read(&vdev->memory_lock);
1588
1589 if (!__vfio_pci_memory_enabled(vdev)) {
1590 ret = VM_FAULT_SIGBUS;
1591 mutex_unlock(&vdev->vma_lock);
1592 goto up_out;
1593 }
1594
1595 if (__vfio_pci_add_vma(vdev, vma)) {
1596 ret = VM_FAULT_OOM;
1597 mutex_unlock(&vdev->vma_lock);
1598 goto up_out;
1599 }
1600
1601 mutex_unlock(&vdev->vma_lock);
1602
1603 if (remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
1604 vma->vm_end - vma->vm_start, vma->vm_page_prot))
1605 ret = VM_FAULT_SIGBUS;
1606
1607up_out:
1608 up_read(&vdev->memory_lock);
1609 return ret;
1610}
1611
1612static const struct vm_operations_struct vfio_pci_mmap_ops = {
1613 .open = vfio_pci_mmap_open,
1614 .close = vfio_pci_mmap_close,
1615 .fault = vfio_pci_mmap_fault,
1616};
1617
1618static int vfio_pci_mmap(void *device_data, struct vm_area_struct *vma)
1619{
1620 struct vfio_pci_device *vdev = device_data;
1621 struct pci_dev *pdev = vdev->pdev;
1622 unsigned int index;
1623 u64 phys_len, req_len, pgoff, req_start;
1624 int ret;
1625
1626 index = vma->vm_pgoff >> (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT);
1627
1628 if (vma->vm_end < vma->vm_start)
1629 return -EINVAL;
1630 if ((vma->vm_flags & VM_SHARED) == 0)
1631 return -EINVAL;
1632 if (index >= VFIO_PCI_NUM_REGIONS) {
1633 int regnum = index - VFIO_PCI_NUM_REGIONS;
1634 struct vfio_pci_region *region = vdev->region + regnum;
1635
1636 if (region && region->ops && region->ops->mmap &&
1637 (region->flags & VFIO_REGION_INFO_FLAG_MMAP))
1638 return region->ops->mmap(vdev, region, vma);
1639 return -EINVAL;
1640 }
1641 if (index >= VFIO_PCI_ROM_REGION_INDEX)
1642 return -EINVAL;
1643 if (!vdev->bar_mmap_supported[index])
1644 return -EINVAL;
1645
1646 phys_len = PAGE_ALIGN(pci_resource_len(pdev, index));
1647 req_len = vma->vm_end - vma->vm_start;
1648 pgoff = vma->vm_pgoff &
1649 ((1U << (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
1650 req_start = pgoff << PAGE_SHIFT;
1651
1652 if (req_start + req_len > phys_len)
1653 return -EINVAL;
1654
1655 /*
1656 * Even though we don't make use of the barmap for the mmap,
1657 * we need to request the region and the barmap tracks that.
1658 */
1659 if (!vdev->barmap[index]) {
1660 ret = pci_request_selected_regions(pdev,
1661 1 << index, "vfio-pci");
1662 if (ret)
1663 return ret;
1664
1665 vdev->barmap[index] = pci_iomap(pdev, index, 0);
1666 if (!vdev->barmap[index]) {
1667 pci_release_selected_regions(pdev, 1 << index);
1668 return -ENOMEM;
1669 }
1670 }
1671
1672 vma->vm_private_data = vdev;
1673 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
1674 vma->vm_pgoff = (pci_resource_start(pdev, index) >> PAGE_SHIFT) + pgoff;
1675
1676 /*
1677 * See remap_pfn_range(), called from vfio_pci_fault() but we can't
1678 * change vm_flags within the fault handler. Set them now.
1679 */
1680 vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;
1681 vma->vm_ops = &vfio_pci_mmap_ops;
1682
1683 return 0;
1684}
1685
1686static void vfio_pci_request(void *device_data, unsigned int count)
1687{
1688 struct vfio_pci_device *vdev = device_data;
1689 struct pci_dev *pdev = vdev->pdev;
1690
1691 mutex_lock(&vdev->igate);
1692
1693 if (vdev->req_trigger) {
1694 if (!(count % 10))
1695 pci_notice_ratelimited(pdev,
1696 "Relaying device request to user (#%u)\n",
1697 count);
1698 eventfd_signal(vdev->req_trigger, 1);
1699 } else if (count == 0) {
1700 pci_warn(pdev,
1701 "No device request channel registered, blocked until released by user\n");
1702 }
1703
1704 mutex_unlock(&vdev->igate);
1705}
1706
1707static int vfio_pci_validate_vf_token(struct vfio_pci_device *vdev,
1708 bool vf_token, uuid_t *uuid)
1709{
1710 /*
1711 * There's always some degree of trust or collaboration between SR-IOV
1712 * PF and VFs, even if just that the PF hosts the SR-IOV capability and
1713 * can disrupt VFs with a reset, but often the PF has more explicit
1714 * access to deny service to the VF or access data passed through the
1715 * VF. We therefore require an opt-in via a shared VF token (UUID) to
1716 * represent this trust. This both prevents that a VF driver might
1717 * assume the PF driver is a trusted, in-kernel driver, and also that
1718 * a PF driver might be replaced with a rogue driver, unknown to in-use
1719 * VF drivers.
1720 *
1721 * Therefore when presented with a VF, if the PF is a vfio device and
1722 * it is bound to the vfio-pci driver, the user needs to provide a VF
1723 * token to access the device, in the form of appending a vf_token to
1724 * the device name, for example:
1725 *
1726 * "0000:04:10.0 vf_token=bd8d9d2b-5a5f-4f5a-a211-f591514ba1f3"
1727 *
1728 * When presented with a PF which has VFs in use, the user must also
1729 * provide the current VF token to prove collaboration with existing
1730 * VF users. If VFs are not in use, the VF token provided for the PF
1731 * device will act to set the VF token.
1732 *
1733 * If the VF token is provided but unused, an error is generated.
1734 */
1735 if (!vdev->pdev->is_virtfn && !vdev->vf_token && !vf_token)
1736 return 0; /* No VF token provided or required */
1737
1738 if (vdev->pdev->is_virtfn) {
1739 struct vfio_device *pf_dev;
1740 struct vfio_pci_device *pf_vdev = get_pf_vdev(vdev, &pf_dev);
1741 bool match;
1742
1743 if (!pf_vdev) {
1744 if (!vf_token)
1745 return 0; /* PF is not vfio-pci, no VF token */
1746
1747 pci_info_ratelimited(vdev->pdev,
1748 "VF token incorrectly provided, PF not bound to vfio-pci\n");
1749 return -EINVAL;
1750 }
1751
1752 if (!vf_token) {
1753 vfio_device_put(pf_dev);
1754 pci_info_ratelimited(vdev->pdev,
1755 "VF token required to access device\n");
1756 return -EACCES;
1757 }
1758
1759 mutex_lock(&pf_vdev->vf_token->lock);
1760 match = uuid_equal(uuid, &pf_vdev->vf_token->uuid);
1761 mutex_unlock(&pf_vdev->vf_token->lock);
1762
1763 vfio_device_put(pf_dev);
1764
1765 if (!match) {
1766 pci_info_ratelimited(vdev->pdev,
1767 "Incorrect VF token provided for device\n");
1768 return -EACCES;
1769 }
1770 } else if (vdev->vf_token) {
1771 mutex_lock(&vdev->vf_token->lock);
1772 if (vdev->vf_token->users) {
1773 if (!vf_token) {
1774 mutex_unlock(&vdev->vf_token->lock);
1775 pci_info_ratelimited(vdev->pdev,
1776 "VF token required to access device\n");
1777 return -EACCES;
1778 }
1779
1780 if (!uuid_equal(uuid, &vdev->vf_token->uuid)) {
1781 mutex_unlock(&vdev->vf_token->lock);
1782 pci_info_ratelimited(vdev->pdev,
1783 "Incorrect VF token provided for device\n");
1784 return -EACCES;
1785 }
1786 } else if (vf_token) {
1787 uuid_copy(&vdev->vf_token->uuid, uuid);
1788 }
1789
1790 mutex_unlock(&vdev->vf_token->lock);
1791 } else if (vf_token) {
1792 pci_info_ratelimited(vdev->pdev,
1793 "VF token incorrectly provided, not a PF or VF\n");
1794 return -EINVAL;
1795 }
1796
1797 return 0;
1798}
1799
1800#define VF_TOKEN_ARG "vf_token="
1801
1802static int vfio_pci_match(void *device_data, char *buf)
1803{
1804 struct vfio_pci_device *vdev = device_data;
1805 bool vf_token = false;
1806 uuid_t uuid;
1807 int ret;
1808
1809 if (strncmp(pci_name(vdev->pdev), buf, strlen(pci_name(vdev->pdev))))
1810 return 0; /* No match */
1811
1812 if (strlen(buf) > strlen(pci_name(vdev->pdev))) {
1813 buf += strlen(pci_name(vdev->pdev));
1814
1815 if (*buf != ' ')
1816 return 0; /* No match: non-whitespace after name */
1817
1818 while (*buf) {
1819 if (*buf == ' ') {
1820 buf++;
1821 continue;
1822 }
1823
1824 if (!vf_token && !strncmp(buf, VF_TOKEN_ARG,
1825 strlen(VF_TOKEN_ARG))) {
1826 buf += strlen(VF_TOKEN_ARG);
1827
1828 if (strlen(buf) < UUID_STRING_LEN)
1829 return -EINVAL;
1830
1831 ret = uuid_parse(buf, &uuid);
1832 if (ret)
1833 return ret;
1834
1835 vf_token = true;
1836 buf += UUID_STRING_LEN;
1837 } else {
1838 /* Unknown/duplicate option */
1839 return -EINVAL;
1840 }
1841 }
1842 }
1843
1844 ret = vfio_pci_validate_vf_token(vdev, vf_token, &uuid);
1845 if (ret)
1846 return ret;
1847
1848 return 1; /* Match */
1849}
1850
1851static const struct vfio_device_ops vfio_pci_ops = {
1852 .name = "vfio-pci",
1853 .open = vfio_pci_open,
1854 .release = vfio_pci_release,
1855 .ioctl = vfio_pci_ioctl,
1856 .read = vfio_pci_read,
1857 .write = vfio_pci_write,
1858 .mmap = vfio_pci_mmap,
1859 .request = vfio_pci_request,
1860 .match = vfio_pci_match,
1861};
1862
1863static int vfio_pci_reflck_attach(struct vfio_pci_device *vdev);
1864static void vfio_pci_reflck_put(struct vfio_pci_reflck *reflck);
1865static struct pci_driver vfio_pci_driver;
1866
1867static int vfio_pci_bus_notifier(struct notifier_block *nb,
1868 unsigned long action, void *data)
1869{
1870 struct vfio_pci_device *vdev = container_of(nb,
1871 struct vfio_pci_device, nb);
1872 struct device *dev = data;
1873 struct pci_dev *pdev = to_pci_dev(dev);
1874 struct pci_dev *physfn = pci_physfn(pdev);
1875
1876 if (action == BUS_NOTIFY_ADD_DEVICE &&
1877 pdev->is_virtfn && physfn == vdev->pdev) {
1878 pci_info(vdev->pdev, "Captured SR-IOV VF %s driver_override\n",
1879 pci_name(pdev));
1880 pdev->driver_override = kasprintf(GFP_KERNEL, "%s",
1881 vfio_pci_ops.name);
1882 } else if (action == BUS_NOTIFY_BOUND_DRIVER &&
1883 pdev->is_virtfn && physfn == vdev->pdev) {
1884 struct pci_driver *drv = pci_dev_driver(pdev);
1885
1886 if (drv && drv != &vfio_pci_driver)
1887 pci_warn(vdev->pdev,
1888 "VF %s bound to driver %s while PF bound to vfio-pci\n",
1889 pci_name(pdev), drv->name);
1890 }
1891
1892 return 0;
1893}
1894
1895static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
1896{
1897 struct vfio_pci_device *vdev;
1898 struct iommu_group *group;
1899 int ret;
1900
1901 if (vfio_pci_is_denylisted(pdev))
1902 return -EINVAL;
1903
1904 if (pdev->hdr_type != PCI_HEADER_TYPE_NORMAL)
1905 return -EINVAL;
1906
1907 /*
1908 * Prevent binding to PFs with VFs enabled, the VFs might be in use
1909 * by the host or other users. We cannot capture the VFs if they
1910 * already exist, nor can we track VF users. Disabling SR-IOV here
1911 * would initiate removing the VFs, which would unbind the driver,
1912 * which is prone to blocking if that VF is also in use by vfio-pci.
1913 * Just reject these PFs and let the user sort it out.
1914 */
1915 if (pci_num_vf(pdev)) {
1916 pci_warn(pdev, "Cannot bind to PF with SR-IOV enabled\n");
1917 return -EBUSY;
1918 }
1919
1920 group = vfio_iommu_group_get(&pdev->dev);
1921 if (!group)
1922 return -EINVAL;
1923
1924 vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);
1925 if (!vdev) {
1926 ret = -ENOMEM;
1927 goto out_group_put;
1928 }
1929
1930 vdev->pdev = pdev;
1931 vdev->irq_type = VFIO_PCI_NUM_IRQS;
1932 mutex_init(&vdev->igate);
1933 spin_lock_init(&vdev->irqlock);
1934 mutex_init(&vdev->ioeventfds_lock);
1935 INIT_LIST_HEAD(&vdev->ioeventfds_list);
1936 mutex_init(&vdev->vma_lock);
1937 INIT_LIST_HEAD(&vdev->vma_list);
1938 init_rwsem(&vdev->memory_lock);
1939
1940 ret = vfio_add_group_dev(&pdev->dev, &vfio_pci_ops, vdev);
1941 if (ret)
1942 goto out_free;
1943
1944 ret = vfio_pci_reflck_attach(vdev);
1945 if (ret)
1946 goto out_del_group_dev;
1947
1948 if (pdev->is_physfn) {
1949 vdev->vf_token = kzalloc(sizeof(*vdev->vf_token), GFP_KERNEL);
1950 if (!vdev->vf_token) {
1951 ret = -ENOMEM;
1952 goto out_reflck;
1953 }
1954
1955 mutex_init(&vdev->vf_token->lock);
1956 uuid_gen(&vdev->vf_token->uuid);
1957
1958 vdev->nb.notifier_call = vfio_pci_bus_notifier;
1959 ret = bus_register_notifier(&pci_bus_type, &vdev->nb);
1960 if (ret)
1961 goto out_vf_token;
1962 }
1963
1964 if (vfio_pci_is_vga(pdev)) {
1965 vga_client_register(pdev, vdev, NULL, vfio_pci_set_vga_decode);
1966 vga_set_legacy_decoding(pdev,
1967 vfio_pci_set_vga_decode(vdev, false));
1968 }
1969
1970 vfio_pci_probe_power_state(vdev);
1971
1972 if (!disable_idle_d3) {
1973 /*
1974 * pci-core sets the device power state to an unknown value at
1975 * bootup and after being removed from a driver. The only
1976 * transition it allows from this unknown state is to D0, which
1977 * typically happens when a driver calls pci_enable_device().
1978 * We're not ready to enable the device yet, but we do want to
1979 * be able to get to D3. Therefore first do a D0 transition
1980 * before going to D3.
1981 */
1982 vfio_pci_set_power_state(vdev, PCI_D0);
1983 vfio_pci_set_power_state(vdev, PCI_D3hot);
1984 }
1985
1986 return ret;
1987
1988out_vf_token:
1989 kfree(vdev->vf_token);
1990out_reflck:
1991 vfio_pci_reflck_put(vdev->reflck);
1992out_del_group_dev:
1993 vfio_del_group_dev(&pdev->dev);
1994out_free:
1995 kfree(vdev);
1996out_group_put:
1997 vfio_iommu_group_put(group, &pdev->dev);
1998 return ret;
1999}
2000
2001static void vfio_pci_remove(struct pci_dev *pdev)
2002{
2003 struct vfio_pci_device *vdev;
2004
2005 pci_disable_sriov(pdev);
2006
2007 vdev = vfio_del_group_dev(&pdev->dev);
2008 if (!vdev)
2009 return;
2010
2011 if (vdev->vf_token) {
2012 WARN_ON(vdev->vf_token->users);
2013 mutex_destroy(&vdev->vf_token->lock);
2014 kfree(vdev->vf_token);
2015 }
2016
2017 if (vdev->nb.notifier_call)
2018 bus_unregister_notifier(&pci_bus_type, &vdev->nb);
2019
2020 vfio_pci_reflck_put(vdev->reflck);
2021
2022 vfio_iommu_group_put(pdev->dev.iommu_group, &pdev->dev);
2023 kfree(vdev->region);
2024 mutex_destroy(&vdev->ioeventfds_lock);
2025
2026 if (!disable_idle_d3)
2027 vfio_pci_set_power_state(vdev, PCI_D0);
2028
2029 kfree(vdev->pm_save);
2030 kfree(vdev);
2031
2032 if (vfio_pci_is_vga(pdev)) {
2033 vga_client_register(pdev, NULL, NULL, NULL);
2034 vga_set_legacy_decoding(pdev,
2035 VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM |
2036 VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM);
2037 }
2038}
2039
2040static pci_ers_result_t vfio_pci_aer_err_detected(struct pci_dev *pdev,
2041 pci_channel_state_t state)
2042{
2043 struct vfio_pci_device *vdev;
2044 struct vfio_device *device;
2045
2046 device = vfio_device_get_from_dev(&pdev->dev);
2047 if (device == NULL)
2048 return PCI_ERS_RESULT_DISCONNECT;
2049
2050 vdev = vfio_device_data(device);
2051 if (vdev == NULL) {
2052 vfio_device_put(device);
2053 return PCI_ERS_RESULT_DISCONNECT;
2054 }
2055
2056 mutex_lock(&vdev->igate);
2057
2058 if (vdev->err_trigger)
2059 eventfd_signal(vdev->err_trigger, 1);
2060
2061 mutex_unlock(&vdev->igate);
2062
2063 vfio_device_put(device);
2064
2065 return PCI_ERS_RESULT_CAN_RECOVER;
2066}
2067
2068static int vfio_pci_sriov_configure(struct pci_dev *pdev, int nr_virtfn)
2069{
2070 struct vfio_pci_device *vdev;
2071 struct vfio_device *device;
2072 int ret = 0;
2073
2074 might_sleep();
2075
2076 if (!enable_sriov)
2077 return -ENOENT;
2078
2079 device = vfio_device_get_from_dev(&pdev->dev);
2080 if (!device)
2081 return -ENODEV;
2082
2083 vdev = vfio_device_data(device);
2084 if (!vdev) {
2085 vfio_device_put(device);
2086 return -ENODEV;
2087 }
2088
2089 if (nr_virtfn == 0)
2090 pci_disable_sriov(pdev);
2091 else
2092 ret = pci_enable_sriov(pdev, nr_virtfn);
2093
2094 vfio_device_put(device);
2095
2096 return ret < 0 ? ret : nr_virtfn;
2097}
2098
2099static const struct pci_error_handlers vfio_err_handlers = {
2100 .error_detected = vfio_pci_aer_err_detected,
2101};
2102
2103static struct pci_driver vfio_pci_driver = {
2104 .name = "vfio-pci",
2105 .id_table = NULL, /* only dynamic ids */
2106 .probe = vfio_pci_probe,
2107 .remove = vfio_pci_remove,
2108 .sriov_configure = vfio_pci_sriov_configure,
2109 .err_handler = &vfio_err_handlers,
2110};
2111
2112static DEFINE_MUTEX(reflck_lock);
2113
2114static struct vfio_pci_reflck *vfio_pci_reflck_alloc(void)
2115{
2116 struct vfio_pci_reflck *reflck;
2117
2118 reflck = kzalloc(sizeof(*reflck), GFP_KERNEL);
2119 if (!reflck)
2120 return ERR_PTR(-ENOMEM);
2121
2122 kref_init(&reflck->kref);
2123 mutex_init(&reflck->lock);
2124
2125 return reflck;
2126}
2127
2128static void vfio_pci_reflck_get(struct vfio_pci_reflck *reflck)
2129{
2130 kref_get(&reflck->kref);
2131}
2132
2133static int vfio_pci_reflck_find(struct pci_dev *pdev, void *data)
2134{
2135 struct vfio_pci_reflck **preflck = data;
2136 struct vfio_device *device;
2137 struct vfio_pci_device *vdev;
2138
2139 device = vfio_device_get_from_dev(&pdev->dev);
2140 if (!device)
2141 return 0;
2142
2143 if (pci_dev_driver(pdev) != &vfio_pci_driver) {
2144 vfio_device_put(device);
2145 return 0;
2146 }
2147
2148 vdev = vfio_device_data(device);
2149
2150 if (vdev->reflck) {
2151 vfio_pci_reflck_get(vdev->reflck);
2152 *preflck = vdev->reflck;
2153 vfio_device_put(device);
2154 return 1;
2155 }
2156
2157 vfio_device_put(device);
2158 return 0;
2159}
2160
2161static int vfio_pci_reflck_attach(struct vfio_pci_device *vdev)
2162{
2163 bool slot = !pci_probe_reset_slot(vdev->pdev->slot);
2164
2165 mutex_lock(&reflck_lock);
2166
2167 if (pci_is_root_bus(vdev->pdev->bus) ||
2168 vfio_pci_for_each_slot_or_bus(vdev->pdev, vfio_pci_reflck_find,
2169 &vdev->reflck, slot) <= 0)
2170 vdev->reflck = vfio_pci_reflck_alloc();
2171
2172 mutex_unlock(&reflck_lock);
2173
2174 return PTR_ERR_OR_ZERO(vdev->reflck);
2175}
2176
2177static void vfio_pci_reflck_release(struct kref *kref)
2178{
2179 struct vfio_pci_reflck *reflck = container_of(kref,
2180 struct vfio_pci_reflck,
2181 kref);
2182
2183 kfree(reflck);
2184 mutex_unlock(&reflck_lock);
2185}
2186
2187static void vfio_pci_reflck_put(struct vfio_pci_reflck *reflck)
2188{
2189 kref_put_mutex(&reflck->kref, vfio_pci_reflck_release, &reflck_lock);
2190}
2191
2192static int vfio_pci_get_unused_devs(struct pci_dev *pdev, void *data)
2193{
2194 struct vfio_devices *devs = data;
2195 struct vfio_device *device;
2196 struct vfio_pci_device *vdev;
2197
2198 if (devs->cur_index == devs->max_index)
2199 return -ENOSPC;
2200
2201 device = vfio_device_get_from_dev(&pdev->dev);
2202 if (!device)
2203 return -EINVAL;
2204
2205 if (pci_dev_driver(pdev) != &vfio_pci_driver) {
2206 vfio_device_put(device);
2207 return -EBUSY;
2208 }
2209
2210 vdev = vfio_device_data(device);
2211
2212 /* Fault if the device is not unused */
2213 if (vdev->refcnt) {
2214 vfio_device_put(device);
2215 return -EBUSY;
2216 }
2217
2218 devs->devices[devs->cur_index++] = device;
2219 return 0;
2220}
2221
2222static int vfio_pci_try_zap_and_vma_lock_cb(struct pci_dev *pdev, void *data)
2223{
2224 struct vfio_devices *devs = data;
2225 struct vfio_device *device;
2226 struct vfio_pci_device *vdev;
2227
2228 if (devs->cur_index == devs->max_index)
2229 return -ENOSPC;
2230
2231 device = vfio_device_get_from_dev(&pdev->dev);
2232 if (!device)
2233 return -EINVAL;
2234
2235 if (pci_dev_driver(pdev) != &vfio_pci_driver) {
2236 vfio_device_put(device);
2237 return -EBUSY;
2238 }
2239
2240 vdev = vfio_device_data(device);
2241
2242 /*
2243 * Locking multiple devices is prone to deadlock, runaway and
2244 * unwind if we hit contention.
2245 */
2246 if (!vfio_pci_zap_and_vma_lock(vdev, true)) {
2247 vfio_device_put(device);
2248 return -EBUSY;
2249 }
2250
2251 devs->devices[devs->cur_index++] = device;
2252 return 0;
2253}
2254
2255/*
2256 * If a bus or slot reset is available for the provided device and:
2257 * - All of the devices affected by that bus or slot reset are unused
2258 * (!refcnt)
2259 * - At least one of the affected devices is marked dirty via
2260 * needs_reset (such as by lack of FLR support)
2261 * Then attempt to perform that bus or slot reset. Callers are required
2262 * to hold vdev->reflck->lock, protecting the bus/slot reset group from
2263 * concurrent opens. A vfio_device reference is acquired for each device
2264 * to prevent unbinds during the reset operation.
2265 *
2266 * NB: vfio-core considers a group to be viable even if some devices are
2267 * bound to drivers like pci-stub or pcieport. Here we require all devices
2268 * to be bound to vfio_pci since that's the only way we can be sure they
2269 * stay put.
2270 */
2271static void vfio_pci_try_bus_reset(struct vfio_pci_device *vdev)
2272{
2273 struct vfio_devices devs = { .cur_index = 0 };
2274 int i = 0, ret = -EINVAL;
2275 bool slot = false;
2276 struct vfio_pci_device *tmp;
2277
2278 if (!pci_probe_reset_slot(vdev->pdev->slot))
2279 slot = true;
2280 else if (pci_probe_reset_bus(vdev->pdev->bus))
2281 return;
2282
2283 if (vfio_pci_for_each_slot_or_bus(vdev->pdev, vfio_pci_count_devs,
2284 &i, slot) || !i)
2285 return;
2286
2287 devs.max_index = i;
2288 devs.devices = kcalloc(i, sizeof(struct vfio_device *), GFP_KERNEL);
2289 if (!devs.devices)
2290 return;
2291
2292 if (vfio_pci_for_each_slot_or_bus(vdev->pdev,
2293 vfio_pci_get_unused_devs,
2294 &devs, slot))
2295 goto put_devs;
2296
2297 /* Does at least one need a reset? */
2298 for (i = 0; i < devs.cur_index; i++) {
2299 tmp = vfio_device_data(devs.devices[i]);
2300 if (tmp->needs_reset) {
2301 ret = pci_reset_bus(vdev->pdev);
2302 break;
2303 }
2304 }
2305
2306put_devs:
2307 for (i = 0; i < devs.cur_index; i++) {
2308 tmp = vfio_device_data(devs.devices[i]);
2309
2310 /*
2311 * If reset was successful, affected devices no longer need
2312 * a reset and we should return all the collateral devices
2313 * to low power. If not successful, we either didn't reset
2314 * the bus or timed out waiting for it, so let's not touch
2315 * the power state.
2316 */
2317 if (!ret) {
2318 tmp->needs_reset = false;
2319
2320 if (tmp != vdev && !disable_idle_d3)
2321 vfio_pci_set_power_state(tmp, PCI_D3hot);
2322 }
2323
2324 vfio_device_put(devs.devices[i]);
2325 }
2326
2327 kfree(devs.devices);
2328}
2329
2330static void __exit vfio_pci_cleanup(void)
2331{
2332 pci_unregister_driver(&vfio_pci_driver);
2333 vfio_pci_uninit_perm_bits();
2334}
2335
2336static void __init vfio_pci_fill_ids(void)
2337{
2338 char *p, *id;
2339 int rc;
2340
2341 /* no ids passed actually */
2342 if (ids[0] == '\0')
2343 return;
2344
2345 /* add ids specified in the module parameter */
2346 p = ids;
2347 while ((id = strsep(&p, ","))) {
2348 unsigned int vendor, device, subvendor = PCI_ANY_ID,
2349 subdevice = PCI_ANY_ID, class = 0, class_mask = 0;
2350 int fields;
2351
2352 if (!strlen(id))
2353 continue;
2354
2355 fields = sscanf(id, "%x:%x:%x:%x:%x:%x",
2356 &vendor, &device, &subvendor, &subdevice,
2357 &class, &class_mask);
2358
2359 if (fields < 2) {
2360 pr_warn("invalid id string \"%s\"\n", id);
2361 continue;
2362 }
2363
2364 rc = pci_add_dynid(&vfio_pci_driver, vendor, device,
2365 subvendor, subdevice, class, class_mask, 0);
2366 if (rc)
2367 pr_warn("failed to add dynamic id [%04x:%04x[%04x:%04x]] class %#08x/%08x (%d)\n",
2368 vendor, device, subvendor, subdevice,
2369 class, class_mask, rc);
2370 else
2371 pr_info("add [%04x:%04x[%04x:%04x]] class %#08x/%08x\n",
2372 vendor, device, subvendor, subdevice,
2373 class, class_mask);
2374 }
2375}
2376
2377static int __init vfio_pci_init(void)
2378{
2379 int ret;
2380
2381 /* Allocate shared config space permision data used by all devices */
2382 ret = vfio_pci_init_perm_bits();
2383 if (ret)
2384 return ret;
2385
2386 /* Register and scan for devices */
2387 ret = pci_register_driver(&vfio_pci_driver);
2388 if (ret)
2389 goto out_driver;
2390
2391 vfio_pci_fill_ids();
2392
2393 if (disable_denylist)
2394 pr_warn("device denylist disabled.\n");
2395
2396 return 0;
2397
2398out_driver:
2399 vfio_pci_uninit_perm_bits();
2400 return ret;
2401}
2402
2403module_init(vfio_pci_init);
2404module_exit(vfio_pci_cleanup);
2405
2406MODULE_VERSION(DRIVER_VERSION);
2407MODULE_LICENSE("GPL v2");
2408MODULE_AUTHOR(DRIVER_AUTHOR);
2409MODULE_DESCRIPTION(DRIVER_DESC);