1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
4  */
5 
6 #ifndef _NE_PCI_DEV_H_
7 #define _NE_PCI_DEV_H_
8 
9 #include <linux/atomic.h>
10 #include <linux/list.h>
11 #include <linux/mutex.h>
12 #include <linux/pci.h>
13 #include <linux/pci_ids.h>
14 #include <linux/wait.h>
15 
16 /**
17  * DOC: Nitro Enclaves (NE) PCI device
18  */
19 
20 /**
21  * PCI_DEVICE_ID_NE - Nitro Enclaves PCI device id.
22  */
23 #define PCI_DEVICE_ID_NE	(0xe4c1)
24 /**
25  * PCI_BAR_NE - Nitro Enclaves PCI device MMIO BAR.
26  */
27 #define PCI_BAR_NE		(0x03)
28 
29 /**
30  * DOC: Device registers in the NE PCI device MMIO BAR
31  */
32 
33 /**
34  * NE_ENABLE - (1 byte) Register to notify the device that the driver is using
35  *	       it (Read/Write).
36  */
37 #define NE_ENABLE		(0x0000)
38 #define NE_ENABLE_OFF		(0x00)
39 #define NE_ENABLE_ON		(0x01)
40 
41 /**
42  * NE_VERSION - (2 bytes) Register to select the device run-time version
43  *		(Read/Write).
44  */
45 #define NE_VERSION		(0x0002)
46 #define NE_VERSION_MAX		(0x0001)
47 
48 /**
49  * NE_COMMAND - (4 bytes) Register to notify the device what command was
50  *		requested (Write-Only).
51  */
52 #define NE_COMMAND		(0x0004)
53 
54 /**
55  * NE_EVTCNT - (4 bytes) Register to notify the driver that a reply or a device
56  *	       event is available (Read-Only):
57  *	       - Lower half  - command reply counter
58  *	       - Higher half - out-of-band device event counter
59  */
60 #define NE_EVTCNT		(0x000c)
61 #define NE_EVTCNT_REPLY_SHIFT	(0)
62 #define NE_EVTCNT_REPLY_MASK	(0x0000ffff)
63 #define NE_EVTCNT_REPLY(cnt)	(((cnt) & NE_EVTCNT_REPLY_MASK) >> \
64 				NE_EVTCNT_REPLY_SHIFT)
65 #define NE_EVTCNT_EVENT_SHIFT	(16)
66 #define NE_EVTCNT_EVENT_MASK	(0xffff0000)
67 #define NE_EVTCNT_EVENT(cnt)	(((cnt) & NE_EVTCNT_EVENT_MASK) >> \
68 				NE_EVTCNT_EVENT_SHIFT)
69 
70 /**
71  * NE_SEND_DATA - (240 bytes) Buffer for sending the command request payload
72  *		  (Read/Write).
73  */
74 #define NE_SEND_DATA		(0x0010)
75 
76 /**
77  * NE_RECV_DATA - (240 bytes) Buffer for receiving the command reply payload
78  *		  (Read-Only).
79  */
80 #define NE_RECV_DATA		(0x0100)
81 
82 /**
83  * DOC: Device MMIO buffer sizes
84  */
85 
86 /**
87  * NE_SEND_DATA_SIZE / NE_RECV_DATA_SIZE - 240 bytes for send / recv buffer.
88  */
89 #define NE_SEND_DATA_SIZE	(240)
90 #define NE_RECV_DATA_SIZE	(240)
91 
92 /**
93  * DOC: MSI-X interrupt vectors
94  */
95 
96 /**
97  * NE_VEC_REPLY - MSI-X vector used for command reply notification.
98  */
99 #define NE_VEC_REPLY		(0)
100 
101 /**
102  * NE_VEC_EVENT - MSI-X vector used for out-of-band events e.g. enclave crash.
103  */
104 #define NE_VEC_EVENT		(1)
105 
106 /**
107  * enum ne_pci_dev_cmd_type - Device command types.
108  * @INVALID_CMD:		Invalid command.
109  * @ENCLAVE_START:		Start an enclave, after setting its resources.
110  * @ENCLAVE_GET_SLOT:		Get the slot uid of an enclave.
111  * @ENCLAVE_STOP:		Terminate an enclave.
112  * @SLOT_ALLOC :		Allocate a slot for an enclave.
113  * @SLOT_FREE:			Free the slot allocated for an enclave
114  * @SLOT_ADD_MEM:		Add a memory region to an enclave slot.
115  * @SLOT_ADD_VCPU:		Add a vCPU to an enclave slot.
116  * @SLOT_COUNT :		Get the number of allocated slots.
117  * @NEXT_SLOT:			Get the next slot in the list of allocated slots.
118  * @SLOT_INFO:			Get the info for a slot e.g. slot uid, vCPUs count.
119  * @SLOT_ADD_BULK_VCPUS:	Add a number of vCPUs, not providing CPU ids.
120  * @MAX_CMD:			A gatekeeper for max possible command type.
121  */
122 enum ne_pci_dev_cmd_type {
123 	INVALID_CMD		= 0,
124 	ENCLAVE_START		= 1,
125 	ENCLAVE_GET_SLOT	= 2,
126 	ENCLAVE_STOP		= 3,
127 	SLOT_ALLOC		= 4,
128 	SLOT_FREE		= 5,
129 	SLOT_ADD_MEM		= 6,
130 	SLOT_ADD_VCPU		= 7,
131 	SLOT_COUNT		= 8,
132 	NEXT_SLOT		= 9,
133 	SLOT_INFO		= 10,
134 	SLOT_ADD_BULK_VCPUS	= 11,
135 	MAX_CMD,
136 };
137 
138 /**
139  * DOC: Device commands - payload structure for requests and replies.
140  */
141 
142 /**
143  * struct enclave_start_req - ENCLAVE_START request.
144  * @slot_uid:		Slot unique id mapped to the enclave to start.
145  * @enclave_cid:	Context ID (CID) for the enclave vsock device.
146  *			If 0, CID is autogenerated.
147  * @flags:		Flags for the enclave to start with (e.g. debug mode).
148  */
149 struct enclave_start_req {
150 	u64	slot_uid;
151 	u64	enclave_cid;
152 	u64	flags;
153 };
154 
155 /**
156  * struct enclave_get_slot_req - ENCLAVE_GET_SLOT request.
157  * @enclave_cid:	Context ID (CID) for the enclave vsock device.
158  */
159 struct enclave_get_slot_req {
160 	u64	enclave_cid;
161 };
162 
163 /**
164  * struct enclave_stop_req - ENCLAVE_STOP request.
165  * @slot_uid:	Slot unique id mapped to the enclave to stop.
166  */
167 struct enclave_stop_req {
168 	u64	slot_uid;
169 };
170 
171 /**
172  * struct slot_alloc_req - SLOT_ALLOC request.
173  * @unused:	In order to avoid weird sizeof edge cases.
174  */
175 struct slot_alloc_req {
176 	u8	unused;
177 };
178 
179 /**
180  * struct slot_free_req - SLOT_FREE request.
181  * @slot_uid:	Slot unique id mapped to the slot to free.
182  */
183 struct slot_free_req {
184 	u64	slot_uid;
185 };
186 
187 /* TODO: Add flags field to the request to add memory region. */
188 /**
189  * struct slot_add_mem_req - SLOT_ADD_MEM request.
190  * @slot_uid:	Slot unique id mapped to the slot to add the memory region to.
191  * @paddr:	Physical address of the memory region to add to the slot.
192  * @size:	Memory size, in bytes, of the memory region to add to the slot.
193  */
194 struct slot_add_mem_req {
195 	u64	slot_uid;
196 	u64	paddr;
197 	u64	size;
198 };
199 
200 /**
201  * struct slot_add_vcpu_req - SLOT_ADD_VCPU request.
202  * @slot_uid:	Slot unique id mapped to the slot to add the vCPU to.
203  * @vcpu_id:	vCPU ID of the CPU to add to the enclave.
204  * @padding:	Padding for the overall data structure.
205  */
206 struct slot_add_vcpu_req {
207 	u64	slot_uid;
208 	u32	vcpu_id;
209 	u8	padding[4];
210 };
211 
212 /**
213  * struct slot_count_req - SLOT_COUNT request.
214  * @unused:	In order to avoid weird sizeof edge cases.
215  */
216 struct slot_count_req {
217 	u8	unused;
218 };
219 
220 /**
221  * struct next_slot_req - NEXT_SLOT request.
222  * @slot_uid:	Slot unique id of the next slot in the iteration.
223  */
224 struct next_slot_req {
225 	u64	slot_uid;
226 };
227 
228 /**
229  * struct slot_info_req - SLOT_INFO request.
230  * @slot_uid:	Slot unique id mapped to the slot to get information about.
231  */
232 struct slot_info_req {
233 	u64	slot_uid;
234 };
235 
236 /**
237  * struct slot_add_bulk_vcpus_req - SLOT_ADD_BULK_VCPUS request.
238  * @slot_uid:	Slot unique id mapped to the slot to add vCPUs to.
239  * @nr_vcpus:	Number of vCPUs to add to the slot.
240  */
241 struct slot_add_bulk_vcpus_req {
242 	u64	slot_uid;
243 	u64	nr_vcpus;
244 };
245 
246 /**
247  * struct ne_pci_dev_cmd_reply - NE PCI device command reply.
248  * @rc :		Return code of the logic that processed the request.
249  * @padding0:		Padding for the overall data structure.
250  * @slot_uid:		Valid for all commands except SLOT_COUNT.
251  * @enclave_cid:	Valid for ENCLAVE_START command.
252  * @slot_count :	Valid for SLOT_COUNT command.
253  * @mem_regions:	Valid for SLOT_ALLOC and SLOT_INFO commands.
254  * @mem_size:		Valid for SLOT_INFO command.
255  * @nr_vcpus:		Valid for SLOT_INFO command.
256  * @flags:		Valid for SLOT_INFO command.
257  * @state:		Valid for SLOT_INFO command.
258  * @padding1:		Padding for the overall data structure.
259  */
260 struct ne_pci_dev_cmd_reply {
261 	s32	rc;
262 	u8	padding0[4];
263 	u64	slot_uid;
264 	u64	enclave_cid;
265 	u64	slot_count;
266 	u64	mem_regions;
267 	u64	mem_size;
268 	u64	nr_vcpus;
269 	u64	flags;
270 	u16	state;
271 	u8	padding1[6];
272 };
273 
274 /**
275  * struct ne_pci_dev - Nitro Enclaves (NE) PCI device.
276  * @cmd_reply_avail:		Variable set if a reply has been sent by the
277  *				PCI device.
278  * @cmd_reply_wait_q:		Wait queue for handling command reply from the
279  *				PCI device.
280  * @enclaves_list:		List of the enclaves managed by the PCI device.
281  * @enclaves_list_mutex:	Mutex for accessing the list of enclaves.
282  * @event_wq:			Work queue for handling out-of-band events
283  *				triggered by the Nitro Hypervisor which require
284  *				enclave state scanning and propagation to the
285  *				enclave process.
286  * @iomem_base :		MMIO region of the PCI device.
287  * @notify_work:		Work item for every received out-of-band event.
288  * @pci_dev_mutex:		Mutex for accessing the PCI device MMIO space.
289  * @pdev:			PCI device data structure.
290  */
291 struct ne_pci_dev {
292 	atomic_t		cmd_reply_avail;
293 	wait_queue_head_t	cmd_reply_wait_q;
294 	struct list_head	enclaves_list;
295 	struct mutex		enclaves_list_mutex;
296 	struct workqueue_struct	*event_wq;
297 	void __iomem		*iomem_base;
298 	struct work_struct	notify_work;
299 	struct mutex		pci_dev_mutex;
300 	struct pci_dev		*pdev;
301 };
302 
303 /**
304  * ne_do_request() - Submit command request to the PCI device based on the command
305  *		     type and retrieve the associated reply.
306  * @pdev:		PCI device to send the command to and receive the reply from.
307  * @cmd_type:		Command type of the request sent to the PCI device.
308  * @cmd_request:	Command request payload.
309  * @cmd_request_size:	Size of the command request payload.
310  * @cmd_reply:		Command reply payload.
311  * @cmd_reply_size:	Size of the command reply payload.
312  *
313  * Context: Process context. This function uses the ne_pci_dev mutex to handle
314  *	    one command at a time.
315  * Return:
316  * * 0 on success.
317  * * Negative return value on failure.
318  */
319 int ne_do_request(struct pci_dev *pdev, enum ne_pci_dev_cmd_type cmd_type,
320 		  void *cmd_request, size_t cmd_request_size,
321 		  struct ne_pci_dev_cmd_reply *cmd_reply,
322 		  size_t cmd_reply_size);
323 
324 /* Nitro Enclaves (NE) PCI device driver */
325 extern struct pci_driver ne_pci_driver;
326 
327 #endif /* _NE_PCI_DEV_H_ */
328