master
  1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
  2/*
  3 * CXL IOCTLs for Memory Devices
  4 */
  5
  6#ifndef _CXL_MEM_H_
  7#define _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(GET_TIMESTAMP, "Get Timestamp"),                             \
 50	___C(GET_LOG_CAPS, "Get Log Capabilities"),			  \
 51	___C(CLEAR_LOG, "Clear Log"),					  \
 52	___C(GET_SUP_LOG_SUBLIST, "Get Supported Logs Sub-List"),	  \
 53	___C(MAX, "invalid / last command")
 54
 55#define ___C(a, b) CXL_MEM_COMMAND_ID_##a
 56#define ___DEPRECATED(a, b) CXL_MEM_DEPRECATED_ID_##a
 57enum { CXL_CMDS };
 58
 59#undef ___C
 60#undef ___DEPRECATED
 61#define ___C(a, b) { b }
 62#define ___DEPRECATED(a, b) { "Deprecated " b }
 63static const struct {
 64	const char *name;
 65} cxl_command_names[] __attribute__((__unused__)) = { CXL_CMDS };
 66
 67/*
 68 * Here's how this actually breaks out:
 69 * cxl_command_names[] = {
 70 *	[CXL_MEM_COMMAND_ID_INVALID] = { "Invalid Command" },
 71 *	[CXL_MEM_COMMAND_ID_IDENTIFY] = { "Identify Command" },
 72 *	...
 73 *	[CXL_MEM_COMMAND_ID_MAX] = { "invalid / last command" },
 74 * };
 75 */
 76
 77#undef ___C
 78#undef ___DEPRECATED
 79#define ___C(a, b) (0)
 80#define ___DEPRECATED(a, b) (1)
 81
 82static const __u8 cxl_deprecated_commands[]
 83	__attribute__((__unused__)) = { CXL_CMDS };
 84
 85/*
 86 * Here's how this actually breaks out:
 87 * cxl_deprecated_commands[] = {
 88 *	[CXL_MEM_COMMAND_ID_INVALID] = 0,
 89 *	[CXL_MEM_COMMAND_ID_IDENTIFY] = 0,
 90 *	...
 91 *	[CXL_MEM_DEPRECATED_ID_GET_POISON] = 1,
 92 *	[CXL_MEM_DEPRECATED_ID_INJECT_POISON] = 1,
 93 *	[CXL_MEM_DEPRECATED_ID_CLEAR_POISON] = 1,
 94 *	...
 95 * };
 96 */
 97
 98#undef ___C
 99#undef ___DEPRECATED
100
101/**
102 * struct cxl_command_info - Command information returned from a query.
103 * @id: ID number for the command.
104 * @flags: Flags that specify command behavior.
105 *
106 *         CXL_MEM_COMMAND_FLAG_USER_ENABLED
107 *
108 *         The given command id is supported by the driver and is supported by
109 *         a related opcode on the device.
110 *
111 *         CXL_MEM_COMMAND_FLAG_EXCLUSIVE
112 *
113 *         Requests with the given command id will terminate with EBUSY as the
114 *         kernel actively owns management of the given resource. For example,
115 *         the label-storage-area can not be written while the kernel is
116 *         actively managing that space.
117 *
118 * @size_in: Expected input size, or ~0 if variable length.
119 * @size_out: Expected output size, or ~0 if variable length.
120 *
121 * Represents a single command that is supported by both the driver and the
122 * hardware. This is returned as part of an array from the query ioctl. The
123 * following would be a command that takes a variable length input and returns 0
124 * bytes of output.
125 *
126 *  - @id = 10
127 *  - @flags = CXL_MEM_COMMAND_FLAG_ENABLED
128 *  - @size_in = ~0
129 *  - @size_out = 0
130 *
131 * See struct cxl_mem_query_commands.
132 */
133struct cxl_command_info {
134	__u32 id;
135
136	__u32 flags;
137#define CXL_MEM_COMMAND_FLAG_MASK		GENMASK(1, 0)
138#define CXL_MEM_COMMAND_FLAG_ENABLED		BIT(0)
139#define CXL_MEM_COMMAND_FLAG_EXCLUSIVE		BIT(1)
140
141	__u32 size_in;
142	__u32 size_out;
143};
144
145/**
146 * struct cxl_mem_query_commands - Query supported commands.
147 * @n_commands: In/out parameter. When @n_commands is > 0, the driver will
148 *		return min(num_support_commands, n_commands). When @n_commands
149 *		is 0, driver will return the number of total supported commands.
150 * @rsvd: Reserved for future use.
151 * @commands: Output array of supported commands. This array must be allocated
152 *            by userspace to be at least min(num_support_commands, @n_commands)
153 *
154 * Allow userspace to query the available commands supported by both the driver,
155 * and the hardware. Commands that aren't supported by either the driver, or the
156 * hardware are not returned in the query.
157 *
158 * Examples:
159 *
160 *  - { .n_commands = 0 } // Get number of supported commands
161 *  - { .n_commands = 15, .commands = buf } // Return first 15 (or less)
162 *    supported commands
163 *
164 *  See struct cxl_command_info.
165 */
166struct cxl_mem_query_commands {
167	/*
168	 * Input: Number of commands to return (space allocated by user)
169	 * Output: Number of commands supported by the driver/hardware
170	 *
171	 * If n_commands is 0, kernel will only return number of commands and
172	 * not try to populate commands[], thus allowing userspace to know how
173	 * much space to allocate
174	 */
175	__u32 n_commands;
176	__u32 rsvd;
177
178	struct cxl_command_info commands[]; /* out: supported commands */
179};
180
181/**
182 * struct cxl_send_command - Send a command to a memory device.
183 * @id: The command to send to the memory device. This must be one of the
184 *	commands returned by the query command.
185 * @flags: Flags for the command (input).
186 * @raw: Special fields for raw commands
187 * @raw.opcode: Opcode passed to hardware when using the RAW command.
188 * @raw.rsvd: Must be zero.
189 * @rsvd: Must be zero.
190 * @retval: Return value from the memory device (output).
191 * @in: Parameters associated with input payload.
192 * @in.size: Size of the payload to provide to the device (input).
193 * @in.rsvd: Must be zero.
194 * @in.payload: Pointer to memory for payload input, payload is little endian.
195 * @out: Parameters associated with output payload.
196 * @out.size: Size of the payload received from the device (input/output). This
197 *	      field is filled in by userspace to let the driver know how much
198 *	      space was allocated for output. It is populated by the driver to
199 *	      let userspace know how large the output payload actually was.
200 * @out.rsvd: Must be zero.
201 * @out.payload: Pointer to memory for payload output, payload is little endian.
202 *
203 * Mechanism for userspace to send a command to the hardware for processing. The
204 * driver will do basic validation on the command sizes. In some cases even the
205 * payload may be introspected. Userspace is required to allocate large enough
206 * buffers for size_out which can be variable length in certain situations.
207 */
208struct cxl_send_command {
209	__u32 id;
210	__u32 flags;
211	union {
212		struct {
213			__u16 opcode;
214			__u16 rsvd;
215		} raw;
216		__u32 rsvd;
217	};
218	__u32 retval;
219
220	struct {
221		__u32 size;
222		__u32 rsvd;
223		__u64 payload;
224	} in;
225
226	struct {
227		__u32 size;
228		__u32 rsvd;
229		__u64 payload;
230	} out;
231};
232
233#endif