libmultipath/prioritizers/alua_spc3.h

   1 /*
   2  * (C) Copyright IBM Corp. 2004, 2005   All Rights Reserved.
   3  *
   4  * spc3.h
   5  *
   6  * Tool to make use of a SCSI-feature called Asymmetric Logical Unit Access.
   7  * It determines the ALUA state of a device and prints a priority value to
   8  * stdout.
   9  *
  10  * Author(s): Jan Kunigk
  11  *            S. Bader <shbader@de.ibm.com>
  12  *
  13  * This file is released under the GPL.
  14  */
  15 #ifndef __SPC3_H__
  16 #define __SPC3_H__
  17 #include "../unaligned.h"
  18
  19 /*=============================================================================
  20  * Definitions to support the standard inquiry command as defined in SPC-3.
  21  * If the evpd (enable vital product data) bit is set the data that will be
  22  * returned is selected by the page field. This field must be 0 if the evpd
  23  * bit is not set.
  24  *=============================================================================
  25  */
  26 #define OPERATION_CODE_INQUIRY          0x12
  27
  28 struct inquiry_command {
  29         unsigned char   op;
  30         unsigned char   b1;             /* xxxxxx.. = reserved               */
  31                                         /* ......x. = obsolete               */
  32                                         /* .......x = evpd                   */
  33         unsigned char   page;
  34         unsigned char   length[2];
  35         unsigned char   control;
  36 } __attribute__((packed));
  37
  38 static inline void
  39 inquiry_command_set_evpd(struct inquiry_command *ic)
  40 {
  41         ic->b1 |= 1;
  42 }
  43
  44 /*-----------------------------------------------------------------------------
  45  * Data returned by the standard inquiry command.
  46  *-----------------------------------------------------------------------------
  47  *
  48  * Peripheral qualifier codes.
  49  */
  50 #define PQ_CONNECTED                                    0x0
  51 #define PQ_DISCONNECTED                                 0x1
  52 #define PQ_UNSUPPORTED                                  0x3
  53
  54 /* Defined peripheral device types. */
  55 #define PDT_DIRECT_ACCESS                               0x00
  56 #define PDT_SEQUENTIAL_ACCESS                           0x01
  57 #define PDT_PRINTER                                     0x02
  58 #define PDT_PROCESSOR                                   0x03
  59 #define PDT_WRITE_ONCE                                  0x04
  60 #define PDT_CD_DVD                                      0x05
  61 #define PDT_SCANNER                                     0x06
  62 #define PDT_OPTICAL_MEMORY                              0x07
  63 #define PDT_MEDIUM_CHANGER                              0x08
  64 #define PDT_COMMUNICATIONS                              0x09
  65 #define PDT_STORAGE_ARRAY_CONTROLLER                    0x0c
  66 #define PDT_ENCLOSURE_SERVICES                          0x0d
  67 #define PDT_SIMPLIFIED_DIRECT_ACCESS                    0x0e
  68 #define PDT_OPTICAL_CARD_READER_WRITER                  0x0f
  69 #define PDT_BRIDGE_CONTROLLER                           0x10
  70 #define PDT_OBJECT_BASED                                0x11
  71 #define PDT_AUTOMATION_INTERFACE                        0x12
  72 #define PDT_LUN                                         0x1e
  73 #define PDT_UNKNOWN                                     0x1f
  74
  75 /* Defined version codes. */
  76 #define VERSION_NONE                                    0x00
  77 #define VERSION_SPC                                     0x03
  78 #define VERSION_SPC2                                    0x04
  79 #define VERSION_SPC3                                    0x05
  80
  81 /* Defined TPGS field values. */
  82 #define TPGS_UNDEF                                       -1
  83 #define TPGS_NONE                                       0x0
  84 #define TPGS_IMPLICIT                                   0x1
  85 #define TPGS_EXPLICIT                                   0x2
  86 #define TPGS_BOTH                                       0x3
  87
  88 struct inquiry_data {
  89         unsigned char   b0;             /* xxx..... = peripheral_qualifier   */
  90                                         /* ...xxxxx = peripheral_device_type */
  91         unsigned char   b1;             /* x....... = removable medium       */
  92                                         /* .xxxxxxx = reserved              */
  93         unsigned char   version;
  94         unsigned char   b3;             /* xx...... = obsolete               */
  95                                         /* ..x..... = normal aca supported   */
  96                                         /* ...x.... = hirarchichal lun supp. */
  97                                         /* ....xxxx = response format        */
  98                                         /*            2 is spc-3 format      */
  99         unsigned char   length;
 100         unsigned char   b5;             /* x....... = storage controller     */
 101                                         /*            component supported    */
 102                                         /* .x...... = access controls coord. */
 103                                         /* ..xx.... = target port group supp.*/
 104                                         /* ....x... = third party copy supp. */
 105                                         /* .....xx. = reserved               */
 106                                         /* .......x = protection info supp.  */
 107         unsigned char   b6;             /* x....... = bque                   */
 108                                         /* .x...... = enclosure services sup.*/
 109                                         /* ..x..... = vs1                    */
 110                                         /* ...x.... = multiport support      */
 111                                         /* ....x... = medium changer         */
 112                                         /* .....xx. = obsolete               */
 113                                         /* .......x = add16                  */
 114         unsigned char   b7;             /* xx...... = obsolete               */
 115                                         /* ..x..... = wbus16                 */
 116                                         /* ...x.... = sync                   */
 117                                         /* ....x... = linked commands supp.  */
 118                                         /* .....x.. = obsolete               */
 119                                         /* ......x. = command queue support  */
 120                                         /* .......x = vs2                    */
 121         unsigned char   vendor_identification[8];
 122         unsigned char   product_identification[16];
 123         unsigned char   product_revision[4];
 124         unsigned char   vendor_specific[20];
 125         unsigned char   b56;            /* xxxx.... = reserved               */
 126                                         /* ....xx.. = clocking               */
 127                                         /* ......x. = qas                    */
 128                                         /* .......x = ius                    */
 129         unsigned char   reserved4;
 130         unsigned char   version_descriptor[8][2];
 131         unsigned char   reserved5[22];
 132         unsigned char   vendor_parameters[0];
 133 } __attribute__((packed));
 134
 135 static inline int
 136 inquiry_data_get_tpgs(struct inquiry_data *id)
 137 {
 138         return (id->b5 >> 4) & 3;
 139 }
 140
 141 /*-----------------------------------------------------------------------------
 142  * Inquiry data returned when requesting vital product data page 0x83.
 143  *-----------------------------------------------------------------------------
 144  */
 145 #define CODESET_BINARY                  0x1
 146 #define CODESET_ACSII                   0x2
 147 #define CODESET_UTF8                    0x3
 148
 149 #define ASSOCIATION_UNIT                0x0
 150 #define ASSOCIATION_PORT                0x1
 151 #define ASSOCIATION_DEVICE              0x2
 152
 153 #define IDTYPE_VENDOR_SPECIFIC          0x0
 154 #define IDTYPE_T10_VENDOR_ID            0x1
 155 #define IDTYPE_EUI64                    0x2
 156 #define IDTYPE_NAA                      0x3
 157 #define IDTYPE_RELATIVE_TPG_ID          0x4
 158 #define IDTYPE_TARGET_PORT_GROUP        0x5
 159 #define IDTYPE_LUN_GROUP                0x6
 160 #define IDTYPE_MD5_LUN_ID               0x7
 161 #define IDTYPE_SCSI_NAME_STRING         0x8
 162
 163 struct vpd83_tpg_dscr {
 164         unsigned char           reserved1[2];
 165         unsigned char           tpg[2];
 166 } __attribute__((packed));
 167
 168 struct vpd83_dscr {
 169         unsigned char           b0;     /* xxxx.... = protocol id            */
 170                                         /* ....xxxx = codeset                */
 171         unsigned char           b1;     /* x....... = protocol id valid      */
 172                                         /* .x...... = reserved               */
 173                                         /* ..xx.... = association            */
 174                                         /* ....xxxx = id type                */
 175         unsigned char           reserved2;
 176         unsigned char           length;                         /* size-4    */
 177         unsigned char           data[0];
 178 } __attribute__((packed));
 179
 180 static inline int
 181 vpd83_dscr_istype(const struct vpd83_dscr *d, unsigned char type)
 182 {
 183         return ((d->b1 & 7) == type);
 184 }
 185
 186 struct vpd83_data {
 187         unsigned char           b0;     /* xxx..... = peripheral_qualifier   */
 188                                         /* ...xxxxx = peripheral_device_type */
 189         unsigned char           page_code;                      /* 0x83      */
 190         unsigned char           length[2];                      /* size-4    */
 191         struct vpd83_dscr       data[0];
 192 } __attribute__((packed));
 193
 194 #define VPD_BUFLEN 4096
 195
 196 /* Returns the max byte offset in the VPD page from the start of the page */
 197 static inline unsigned int vpd83_max_offs(const struct vpd83_data *p)
 198 {
 199         uint16_t len = get_unaligned_be16(p->length) + 4;
 200
 201         return len <= VPD_BUFLEN ? len : VPD_BUFLEN;
 202 }
 203
 204 static inline bool
 205 vpd83_descr_fits(const struct vpd83_dscr *d, const struct vpd83_data *p)
 206 {
 207         ptrdiff_t max_offs = vpd83_max_offs(p);
 208         ptrdiff_t offs = ((const char *)d - (const char *)p);
 209
 210         /* make sure we can read d->length */
 211         if (offs < 0 || offs > max_offs - 4)
 212                 return false;
 213
 214         offs += d->length + 4;
 215         return offs <= max_offs;
 216 }
 217
 218 static inline const struct vpd83_dscr *
 219 vpd83_next_dscr(const struct vpd83_dscr *d, const struct vpd83_data *p)
 220 {
 221         ptrdiff_t offs = ((const char *)d - (const char *)p) + d->length + 4;
 222
 223         return (const struct vpd83_dscr *)((const char *)p + offs);
 224 }
 225
 226 /*-----------------------------------------------------------------------------
 227  * This macro should be used to walk through all identification descriptors
 228  * defined in the code page 0x83.
 229  * The argument p is a pointer to the code page 0x83 data and d is used to
 230  * point to the current descriptor.
 231  *-----------------------------------------------------------------------------
 232  */
 233 #define FOR_EACH_VPD83_DSCR(p, d) \
 234                 for( \
 235                         d = p->data;              \
 236                         vpd83_descr_fits(d, p);   \
 237                         d = vpd83_next_dscr(d, p) \
 238                 )
 239
 240 /*=============================================================================
 241  * The following structures and macros are used to call the report target port
 242  * groups command defined in SPC-3.
 243  * This command is used to get information about the target port groups (which
 244  * states are supported, which ports belong to this group, and so on) and the
 245  * current state of each target port group.
 246  *=============================================================================
 247  */
 248 #define OPERATION_CODE_RTPG             0xa3
 249 #define SERVICE_ACTION_RTPG             0x0a
 250
 251 struct rtpg_command {
 252         unsigned char           op;     /* 0xa3                              */
 253         unsigned char           b1;     /* xxx..... = reserved               */
 254                                         /* ...xxxxx = service action (0x0a)  */
 255         unsigned char                   reserved2[4];
 256         unsigned char                   length[4];
 257         unsigned char                   reserved3;
 258         unsigned char                   control;
 259 } __attribute__((packed));
 260
 261 static inline void
 262 rtpg_command_set_service_action(struct rtpg_command *cmd)
 263 {
 264         cmd->b1 = (cmd->b1 & 0xe0) | SERVICE_ACTION_RTPG;
 265 }
 266
 267 struct rtpg_tp_dscr {
 268         unsigned char                   obsolete1[2];
 269         /* The Relative Target Port Identifier of a target port. */
 270         unsigned char                   rtpi[2];
 271 } __attribute__((packed));
 272
 273 #define AAS_OPTIMIZED                   0x0
 274 #define AAS_NON_OPTIMIZED               0x1
 275 #define AAS_STANDBY                     0x2
 276 #define AAS_UNAVAILABLE                 0x3
 277 #define AAS_LBA_DEPENDENT               0x4
 278 #define AAS_RESERVED                    0x5
 279 #define AAS_OFFLINE                     0xe
 280 #define AAS_TRANSITIONING               0xf
 281
 282 #define TPG_STATUS_NONE                 0x0
 283 #define TPG_STATUS_SET                  0x1
 284 #define TPG_STATUS_IMPLICIT_CHANGE      0x2
 285
 286 struct rtpg_tpg_dscr {
 287         unsigned char   b0;             /* x....... = pref(ered) port        */
 288                                         /* .xxx.... = reserved               */
 289                                         /* ....xxxx = asymmetric access state*/
 290         unsigned char   b1;             /* xxx..... = reserved               */
 291                                         /* ...x.... = LBA dependent support  */
 292                                         /* ....x... = unavailable support    */
 293                                         /* .....x.. = standby support        */
 294                                         /* ......x. = non-optimized support  */
 295                                         /* .......x = optimized support      */
 296         unsigned char                   tpg[2];
 297         unsigned char                   reserved3;
 298         unsigned char                   status;
 299         unsigned char                   vendor_unique;
 300         unsigned char                   port_count;
 301         struct rtpg_tp_dscr             data[0];
 302 } __attribute__((packed));
 303
 304 static inline int
 305 rtpg_tpg_dscr_get_aas(struct rtpg_tpg_dscr *d)
 306 {
 307         return (d->b0 & 0x8f);
 308 }
 309
 310 struct rtpg_data {
 311         unsigned char                   length[4];              /* size-4 */
 312         struct rtpg_tpg_dscr            data[0];
 313 } __attribute__((packed));
 314
 315 #define RTPG_FOR_EACH_PORT_GROUP(p, g) \
 316                 for( \
 317                         g = &(p->data[0]); \
 318                         ((char *) g) < ((char *) p) + get_unaligned_be32(p->length); \
 319                         g = (struct rtpg_tpg_dscr *) ( \
 320                                 ((char *) g) + \
 321                                 sizeof(struct rtpg_tpg_dscr) + \
 322                                 g->port_count * sizeof(struct rtpg_tp_dscr) \
 323                         ) \
 324                 )
 325
 326 #endif /* __SPC3_H__ */