1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2 /*
3  * CXL IOCTLs for Memory Devices
4  */
5 
6 #ifndef _UAPI_CXL_MEM_H_
7 #define _UAPI_CXL_MEM_H_
8 
9 #include <linux/types.h>
10 
11 /**
12  * DOC: UAPI
13  *
14  * Not all of the commands that the driver supports are available for use by
15  * userspace at all times.  Userspace can check the result of the QUERY command
16  * to determine the live set of commands.  Alternatively, it can issue the
17  * command and check for failure.
18  */
19 
20 #define CXL_MEM_QUERY_COMMANDS _IOR(0xCE, 1, struct cxl_mem_query_commands)
21 #define CXL_MEM_SEND_COMMAND _IOWR(0xCE, 2, struct cxl_send_command)
22 
23 /*
24  * NOTE: New defines must be added to the end of the list to preserve
25  * compatibility because this enum is exported to user space.
26  */
27 #define CXL_CMDS                                                          \
28 	___C(INVALID, "Invalid Command"),                                 \
29 	___C(IDENTIFY, "Identify Command"),                               \
30 	___C(RAW, "Raw device command"),                                  \
31 	___C(GET_SUPPORTED_LOGS, "Get Supported Logs"),                   \
32 	___C(GET_FW_INFO, "Get FW Info"),                                 \
33 	___C(GET_PARTITION_INFO, "Get Partition Information"),            \
34 	___C(GET_LSA, "Get Label Storage Area"),                          \
35 	___C(GET_HEALTH_INFO, "Get Health Info"),                         \
36 	___C(GET_LOG, "Get Log"),                                         \
37 	___C(SET_PARTITION_INFO, "Set Partition Information"),            \
38 	___C(SET_LSA, "Set Label Storage Area"),                          \
39 	___C(GET_ALERT_CONFIG, "Get Alert Configuration"),                \
40 	___C(SET_ALERT_CONFIG, "Set Alert Configuration"),                \
41 	___C(GET_SHUTDOWN_STATE, "Get Shutdown State"),                   \
42 	___C(SET_SHUTDOWN_STATE, "Set Shutdown State"),                   \
43 	___DEPRECATED(GET_POISON, "Get Poison List"),                     \
44 	___DEPRECATED(INJECT_POISON, "Inject Poison"),                    \
45 	___DEPRECATED(CLEAR_POISON, "Clear Poison"),                      \
46 	___C(GET_SCAN_MEDIA_CAPS, "Get Scan Media Capabilities"),         \
47 	___DEPRECATED(SCAN_MEDIA, "Scan Media"),                          \
48 	___DEPRECATED(GET_SCAN_MEDIA, "Get Scan Media Results"),          \
49 	___C(MAX, "invalid / last command")
50 
51 #define ___C(a, b) CXL_MEM_COMMAND_ID_##a
52 #define ___DEPRECATED(a, b) CXL_MEM_DEPRECATED_ID_##a
53 enum { CXL_CMDS };
54 
55 #undef ___C
56 #undef ___DEPRECATED
57 #define ___C(a, b) { b }
58 #define ___DEPRECATED(a, b) { "Deprecated " b }
59 static const struct {
60 	const char *name;
61 } cxl_command_names[] __attribute__((__unused__)) = { CXL_CMDS };
62 
63 /*
64  * Here's how this actually breaks out:
65  * cxl_command_names[] = {
66  *	[CXL_MEM_COMMAND_ID_INVALID] = { "Invalid Command" },
67  *	[CXL_MEM_COMMAND_ID_IDENTIFY] = { "Identify Command" },
68  *	...
69  *	[CXL_MEM_COMMAND_ID_MAX] = { "invalid / last command" },
70  * };
71  */
72 
73 #undef ___C
74 #undef ___DEPRECATED
75 #define ___C(a, b) (0)
76 #define ___DEPRECATED(a, b) (1)
77 
78 static const __u8 cxl_deprecated_commands[]
79 	__attribute__((__unused__)) = { CXL_CMDS };
80 
81 /*
82  * Here's how this actually breaks out:
83  * cxl_deprecated_commands[] = {
84  *	[CXL_MEM_COMMAND_ID_INVALID] = 0,
85  *	[CXL_MEM_COMMAND_ID_IDENTIFY] = 0,
86  *	...
87  *	[CXL_MEM_DEPRECATED_ID_GET_POISON] = 1,
88  *	[CXL_MEM_DEPRECATED_ID_INJECT_POISON] = 1,
89  *	[CXL_MEM_DEPRECATED_ID_CLEAR_POISON] = 1,
90  *	...
91  * };
92  */
93 
94 #undef ___C
95 #undef ___DEPRECATED
96 
97 /**
98  * struct cxl_command_info - Command information returned from a query.
99  * @id: ID number for the command.
100  * @flags: Flags that specify command behavior.
101  *
102  *         CXL_MEM_COMMAND_FLAG_USER_ENABLED
103  *
104  *         The given command id is supported by the driver and is supported by
105  *         a related opcode on the device.
106  *
107  *         CXL_MEM_COMMAND_FLAG_EXCLUSIVE
108  *
109  *         Requests with the given command id will terminate with EBUSY as the
110  *         kernel actively owns management of the given resource. For example,
111  *         the label-storage-area can not be written while the kernel is
112  *         actively managing that space.
113  *
114  * @size_in: Expected input size, or ~0 if variable length.
115  * @size_out: Expected output size, or ~0 if variable length.
116  *
117  * Represents a single command that is supported by both the driver and the
118  * hardware. This is returned as part of an array from the query ioctl. The
119  * following would be a command that takes a variable length input and returns 0
120  * bytes of output.
121  *
122  *  - @id = 10
123  *  - @flags = CXL_MEM_COMMAND_FLAG_ENABLED
124  *  - @size_in = ~0
125  *  - @size_out = 0
126  *
127  * See struct cxl_mem_query_commands.
128  */
129 struct cxl_command_info {
130 	__u32 id;
131 
132 	__u32 flags;
133 #define CXL_MEM_COMMAND_FLAG_MASK		GENMASK(1, 0)
134 #define CXL_MEM_COMMAND_FLAG_ENABLED		BIT(0)
135 #define CXL_MEM_COMMAND_FLAG_EXCLUSIVE		BIT(1)
136 
137 	__u32 size_in;
138 	__u32 size_out;
139 };
140 
141 /**
142  * struct cxl_mem_query_commands - Query supported commands.
143  * @n_commands: In/out parameter. When @n_commands is > 0, the driver will
144  *		return min(num_support_commands, n_commands). When @n_commands
145  *		is 0, driver will return the number of total supported commands.
146  * @rsvd: Reserved for future use.
147  * @commands: Output array of supported commands. This array must be allocated
148  *            by userspace to be at least min(num_support_commands, @n_commands)
149  *
150  * Allow userspace to query the available commands supported by both the driver,
151  * and the hardware. Commands that aren't supported by either the driver, or the
152  * hardware are not returned in the query.
153  *
154  * Examples:
155  *
156  *  - { .n_commands = 0 } // Get number of supported commands
157  *  - { .n_commands = 15, .commands = buf } // Return first 15 (or less)
158  *    supported commands
159  *
160  *  See struct cxl_command_info.
161  */
162 struct cxl_mem_query_commands {
163 	/*
164 	 * Input: Number of commands to return (space allocated by user)
165 	 * Output: Number of commands supported by the driver/hardware
166 	 *
167 	 * If n_commands is 0, kernel will only return number of commands and
168 	 * not try to populate commands[], thus allowing userspace to know how
169 	 * much space to allocate
170 	 */
171 	__u32 n_commands;
172 	__u32 rsvd;
173 
174 	struct cxl_command_info __user commands[]; /* out: supported commands */
175 };
176 
177 /**
178  * struct cxl_send_command - Send a command to a memory device.
179  * @id: The command to send to the memory device. This must be one of the
180  *	commands returned by the query command.
181  * @flags: Flags for the command (input).
182  * @raw: Special fields for raw commands
183  * @raw.opcode: Opcode passed to hardware when using the RAW command.
184  * @raw.rsvd: Must be zero.
185  * @rsvd: Must be zero.
186  * @retval: Return value from the memory device (output).
187  * @in: Parameters associated with input payload.
188  * @in.size: Size of the payload to provide to the device (input).
189  * @in.rsvd: Must be zero.
190  * @in.payload: Pointer to memory for payload input, payload is little endian.
191  * @out: Parameters associated with output payload.
192  * @out.size: Size of the payload received from the device (input/output). This
193  *	      field is filled in by userspace to let the driver know how much
194  *	      space was allocated for output. It is populated by the driver to
195  *	      let userspace know how large the output payload actually was.
196  * @out.rsvd: Must be zero.
197  * @out.payload: Pointer to memory for payload output, payload is little endian.
198  *
199  * Mechanism for userspace to send a command to the hardware for processing. The
200  * driver will do basic validation on the command sizes. In some cases even the
201  * payload may be introspected. Userspace is required to allocate large enough
202  * buffers for size_out which can be variable length in certain situations.
203  */
204 struct cxl_send_command {
205 	__u32 id;
206 	__u32 flags;
207 	union {
208 		struct {
209 			__u16 opcode;
210 			__u16 rsvd;
211 		} raw;
212 		__u32 rsvd;
213 	};
214 	__u32 retval;
215 
216 	struct {
217 		__u32 size;
218 		__u32 rsvd;
219 		__u64 payload;
220 	} in;
221 
222 	struct {
223 		__u32 size;
224 		__u32 rsvd;
225 		__u64 payload;
226 	} out;
227 };
228 
229 #endif
230