uapi/linux/cxl_mem.h

0001 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
0002 /*
0003  * CXL IOCTLs for Memory Devices
0004  */
0005
0006 #ifndef _UAPI_CXL_MEM_H_
0007 #define _UAPI_CXL_MEM_H_
0008
0009 #include <linux/types.h>
0010
0011 /**
0012  * DOC: UAPI
0013  *
0014  * Not all of all commands that the driver supports are always available for use
0015  * by userspace. Userspace must check the results from the QUERY command in
0016  * order to determine the live set of commands.
0017  */
0018
0019 #define CXL_MEM_QUERY_COMMANDS _IOR(0xCE, 1, struct cxl_mem_query_commands)
0020 #define CXL_MEM_SEND_COMMAND _IOWR(0xCE, 2, struct cxl_send_command)
0021
0022 #define CXL_CMDS                                                          \
0023     ___C(INVALID, "Invalid Command"),                                 \
0024     ___C(IDENTIFY, "Identify Command"),                               \
0025     ___C(RAW, "Raw device command"),                                  \
0026     ___C(GET_SUPPORTED_LOGS, "Get Supported Logs"),                   \
0027     ___C(GET_FW_INFO, "Get FW Info"),                                 \
0028     ___C(GET_PARTITION_INFO, "Get Partition Information"),            \
0029     ___C(GET_LSA, "Get Label Storage Area"),                          \
0030     ___C(GET_HEALTH_INFO, "Get Health Info"),                         \
0031     ___C(GET_LOG, "Get Log"),                                         \
0032     ___C(SET_PARTITION_INFO, "Set Partition Information"),            \
0033     ___C(SET_LSA, "Set Label Storage Area"),                          \
0034     ___C(GET_ALERT_CONFIG, "Get Alert Configuration"),                \
0035     ___C(SET_ALERT_CONFIG, "Set Alert Configuration"),                \
0036     ___C(GET_SHUTDOWN_STATE, "Get Shutdown State"),                   \
0037     ___C(SET_SHUTDOWN_STATE, "Set Shutdown State"),                   \
0038     ___C(GET_POISON, "Get Poison List"),                              \
0039     ___C(INJECT_POISON, "Inject Poison"),                             \
0040     ___C(CLEAR_POISON, "Clear Poison"),                               \
0041     ___C(GET_SCAN_MEDIA_CAPS, "Get Scan Media Capabilities"),         \
0042     ___C(SCAN_MEDIA, "Scan Media"),                                   \
0043     ___C(GET_SCAN_MEDIA, "Get Scan Media Results"),                   \
0044     ___C(MAX, "invalid / last command")
0045
0046 #define ___C(a, b) CXL_MEM_COMMAND_ID_##a
0047 enum { CXL_CMDS };
0048
0049 #undef ___C
0050 #define ___C(a, b) { b }
0051 static const struct {
0052     const char *name;
0053 } cxl_command_names[] __attribute__((__unused__)) = { CXL_CMDS };
0054
0055 /*
0056  * Here's how this actually breaks out:
0057  * cxl_command_names[] = {
0058  *  [CXL_MEM_COMMAND_ID_INVALID] = { "Invalid Command" },
0059  *  [CXL_MEM_COMMAND_ID_IDENTIFY] = { "Identify Command" },
0060  *  ...
0061  *  [CXL_MEM_COMMAND_ID_MAX] = { "invalid / last command" },
0062  * };
0063  */
0064
0065 #undef ___C
0066
0067 /**
0068  * struct cxl_command_info - Command information returned from a query.
0069  * @id: ID number for the command.
0070  * @flags: Flags that specify command behavior.
0071  * @size_in: Expected input size, or ~0 if variable length.
0072  * @size_out: Expected output size, or ~0 if variable length.
0073  *
0074  * Represents a single command that is supported by both the driver and the
0075  * hardware. This is returned as part of an array from the query ioctl. The
0076  * following would be a command that takes a variable length input and returns 0
0077  * bytes of output.
0078  *
0079  *  - @id = 10
0080  *  - @flags = 0
0081  *  - @size_in = ~0
0082  *  - @size_out = 0
0083  *
0084  * See struct cxl_mem_query_commands.
0085  */
0086 struct cxl_command_info {
0087     __u32 id;
0088
0089     __u32 flags;
0090 #define CXL_MEM_COMMAND_FLAG_MASK GENMASK(0, 0)
0091
0092     __u32 size_in;
0093     __u32 size_out;
0094 };
0095
0096 /**
0097  * struct cxl_mem_query_commands - Query supported commands.
0098  * @n_commands: In/out parameter. When @n_commands is > 0, the driver will
0099  *      return min(num_support_commands, n_commands). When @n_commands
0100  *      is 0, driver will return the number of total supported commands.
0101  * @rsvd: Reserved for future use.
0102  * @commands: Output array of supported commands. This array must be allocated
0103  *            by userspace to be at least min(num_support_commands, @n_commands)
0104  *
0105  * Allow userspace to query the available commands supported by both the driver,
0106  * and the hardware. Commands that aren't supported by either the driver, or the
0107  * hardware are not returned in the query.
0108  *
0109  * Examples:
0110  *
0111  *  - { .n_commands = 0 } // Get number of supported commands
0112  *  - { .n_commands = 15, .commands = buf } // Return first 15 (or less)
0113  *    supported commands
0114  *
0115  *  See struct cxl_command_info.
0116  */
0117 struct cxl_mem_query_commands {
0118     /*
0119      * Input: Number of commands to return (space allocated by user)
0120      * Output: Number of commands supported by the driver/hardware
0121      *
0122      * If n_commands is 0, kernel will only return number of commands and
0123      * not try to populate commands[], thus allowing userspace to know how
0124      * much space to allocate
0125      */
0126     __u32 n_commands;
0127     __u32 rsvd;
0128
0129     struct cxl_command_info __user commands[]; /* out: supported commands */
0130 };
0131
0132 /**
0133  * struct cxl_send_command - Send a command to a memory device.
0134  * @id: The command to send to the memory device. This must be one of the
0135  *  commands returned by the query command.
0136  * @flags: Flags for the command (input).
0137  * @raw: Special fields for raw commands
0138  * @raw.opcode: Opcode passed to hardware when using the RAW command.
0139  * @raw.rsvd: Must be zero.
0140  * @rsvd: Must be zero.
0141  * @retval: Return value from the memory device (output).
0142  * @in: Parameters associated with input payload.
0143  * @in.size: Size of the payload to provide to the device (input).
0144  * @in.rsvd: Must be zero.
0145  * @in.payload: Pointer to memory for payload input, payload is little endian.
0146  * @out: Parameters associated with output payload.
0147  * @out.size: Size of the payload received from the device (input/output). This
0148  *        field is filled in by userspace to let the driver know how much
0149  *        space was allocated for output. It is populated by the driver to
0150  *        let userspace know how large the output payload actually was.
0151  * @out.rsvd: Must be zero.
0152  * @out.payload: Pointer to memory for payload output, payload is little endian.
0153  *
0154  * Mechanism for userspace to send a command to the hardware for processing. The
0155  * driver will do basic validation on the command sizes. In some cases even the
0156  * payload may be introspected. Userspace is required to allocate large enough
0157  * buffers for size_out which can be variable length in certain situations.
0158  */
0159 struct cxl_send_command {
0160     __u32 id;
0161     __u32 flags;
0162     union {
0163         struct {
0164             __u16 opcode;
0165             __u16 rsvd;
0166         } raw;
0167         __u32 rsvd;
0168     };
0169     __u32 retval;
0170
0171     struct {
0172         __u32 size;
0173         __u32 rsvd;
0174         __u64 payload;
0175     } in;
0176
0177     struct {
0178         __u32 size;
0179         __u32 rsvd;
0180         __u64 payload;
0181     } out;
0182 };
0183
0184 #endif