include/uapi/linux/cxl_mem.h

   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(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
  57 enum { CXL_CMDS };
  58
  59 #undef ___C
  60 #undef ___DEPRECATED
  61 #define ___C(a, b) { b }
  62 #define ___DEPRECATED(a, b) { "Deprecated " b }
  63 static 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
  82 static 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  */
 133 struct 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  */
 166 struct 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 __user 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  */
 208 struct 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