1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Functions for assembling fcx enabled I/O control blocks. 4 * 5 * Copyright IBM Corp. 2008 6 * Author(s): Peter Oberparleiter <peter.oberparleiter@de.ibm.com> 7 */ 8 9 #include <linux/kernel.h> 10 #include <linux/types.h> 11 #include <linux/string.h> 12 #include <linux/errno.h> 13 #include <linux/err.h> 14 #include <linux/module.h> 15 #include <asm/fcx.h> 16 #include "cio.h" 17 18 /** 19 * tcw_get_intrg - return pointer to associated interrogate tcw 20 * @tcw: pointer to the original tcw 21 * 22 * Return a pointer to the interrogate tcw associated with the specified tcw 23 * or %NULL if there is no associated interrogate tcw. 24 */ 25 struct tcw *tcw_get_intrg(struct tcw *tcw) 26 { 27 return (struct tcw *) ((addr_t) tcw->intrg); 28 } 29 EXPORT_SYMBOL(tcw_get_intrg); 30 31 /** 32 * tcw_get_data - return pointer to input/output data associated with tcw 33 * @tcw: pointer to the tcw 34 * 35 * Return the input or output data address specified in the tcw depending 36 * on whether the r-bit or the w-bit is set. If neither bit is set, return 37 * %NULL. 38 */ 39 void *tcw_get_data(struct tcw *tcw) 40 { 41 if (tcw->r) 42 return (void *) ((addr_t) tcw->input); 43 if (tcw->w) 44 return (void *) ((addr_t) tcw->output); 45 return NULL; 46 } 47 EXPORT_SYMBOL(tcw_get_data); 48 49 /** 50 * tcw_get_tccb - return pointer to tccb associated with tcw 51 * @tcw: pointer to the tcw 52 * 53 * Return pointer to the tccb associated with this tcw. 54 */ 55 struct tccb *tcw_get_tccb(struct tcw *tcw) 56 { 57 return (struct tccb *) ((addr_t) tcw->tccb); 58 } 59 EXPORT_SYMBOL(tcw_get_tccb); 60 61 /** 62 * tcw_get_tsb - return pointer to tsb associated with tcw 63 * @tcw: pointer to the tcw 64 * 65 * Return pointer to the tsb associated with this tcw. 66 */ 67 struct tsb *tcw_get_tsb(struct tcw *tcw) 68 { 69 return (struct tsb *) ((addr_t) tcw->tsb); 70 } 71 EXPORT_SYMBOL(tcw_get_tsb); 72 73 /** 74 * tcw_init - initialize tcw data structure 75 * @tcw: pointer to the tcw to be initialized 76 * @r: initial value of the r-bit 77 * @w: initial value of the w-bit 78 * 79 * Initialize all fields of the specified tcw data structure with zero and 80 * fill in the format, flags, r and w fields. 81 */ 82 void tcw_init(struct tcw *tcw, int r, int w) 83 { 84 memset(tcw, 0, sizeof(struct tcw)); 85 tcw->format = TCW_FORMAT_DEFAULT; 86 tcw->flags = TCW_FLAGS_TIDAW_FORMAT(TCW_TIDAW_FORMAT_DEFAULT); 87 if (r) 88 tcw->r = 1; 89 if (w) 90 tcw->w = 1; 91 } 92 EXPORT_SYMBOL(tcw_init); 93 94 static inline size_t tca_size(struct tccb *tccb) 95 { 96 return tccb->tcah.tcal - 12; 97 } 98 99 static u32 calc_dcw_count(struct tccb *tccb) 100 { 101 int offset; 102 struct dcw *dcw; 103 u32 count = 0; 104 size_t size; 105 106 size = tca_size(tccb); 107 for (offset = 0; offset < size;) { 108 dcw = (struct dcw *) &tccb->tca[offset]; 109 count += dcw->count; 110 if (!(dcw->flags & DCW_FLAGS_CC)) 111 break; 112 offset += sizeof(struct dcw) + ALIGN((int) dcw->cd_count, 4); 113 } 114 return count; 115 } 116 117 static u32 calc_cbc_size(struct tidaw *tidaw, int num) 118 { 119 int i; 120 u32 cbc_data; 121 u32 cbc_count = 0; 122 u64 data_count = 0; 123 124 for (i = 0; i < num; i++) { 125 if (tidaw[i].flags & TIDAW_FLAGS_LAST) 126 break; 127 /* TODO: find out if padding applies to total of data 128 * transferred or data transferred by this tidaw. Assumption: 129 * applies to total. */ 130 data_count += tidaw[i].count; 131 if (tidaw[i].flags & TIDAW_FLAGS_INSERT_CBC) { 132 cbc_data = 4 + ALIGN(data_count, 4) - data_count; 133 cbc_count += cbc_data; 134 data_count += cbc_data; 135 } 136 } 137 return cbc_count; 138 } 139 140 /** 141 * tcw_finalize - finalize tcw length fields and tidaw list 142 * @tcw: pointer to the tcw 143 * @num_tidaws: the number of tidaws used to address input/output data or zero 144 * if no tida is used 145 * 146 * Calculate the input-/output-count and tccbl field in the tcw, add a 147 * tcat the tccb and terminate the data tidaw list if used. 148 * 149 * Note: in case input- or output-tida is used, the tidaw-list must be stored 150 * in contiguous storage (no ttic). The tcal field in the tccb must be 151 * up-to-date. 152 */ 153 void tcw_finalize(struct tcw *tcw, int num_tidaws) 154 { 155 struct tidaw *tidaw; 156 struct tccb *tccb; 157 struct tccb_tcat *tcat; 158 u32 count; 159 160 /* Terminate tidaw list. */ 161 tidaw = tcw_get_data(tcw); 162 if (num_tidaws > 0) 163 tidaw[num_tidaws - 1].flags |= TIDAW_FLAGS_LAST; 164 /* Add tcat to tccb. */ 165 tccb = tcw_get_tccb(tcw); 166 tcat = (struct tccb_tcat *) &tccb->tca[tca_size(tccb)]; 167 memset(tcat, 0, sizeof(*tcat)); 168 /* Calculate tcw input/output count and tcat transport count. */ 169 count = calc_dcw_count(tccb); 170 if (tcw->w && (tcw->flags & TCW_FLAGS_OUTPUT_TIDA)) 171 count += calc_cbc_size(tidaw, num_tidaws); 172 if (tcw->r) 173 tcw->input_count = count; 174 else if (tcw->w) 175 tcw->output_count = count; 176 tcat->count = ALIGN(count, 4) + 4; 177 /* Calculate tccbl. */ 178 tcw->tccbl = (sizeof(struct tccb) + tca_size(tccb) + 179 sizeof(struct tccb_tcat) - 20) >> 2; 180 } 181 EXPORT_SYMBOL(tcw_finalize); 182 183 /** 184 * tcw_set_intrg - set the interrogate tcw address of a tcw 185 * @tcw: the tcw address 186 * @intrg_tcw: the address of the interrogate tcw 187 * 188 * Set the address of the interrogate tcw in the specified tcw. 189 */ 190 void tcw_set_intrg(struct tcw *tcw, struct tcw *intrg_tcw) 191 { 192 tcw->intrg = (u32) ((addr_t) intrg_tcw); 193 } 194 EXPORT_SYMBOL(tcw_set_intrg); 195 196 /** 197 * tcw_set_data - set data address and tida flag of a tcw 198 * @tcw: the tcw address 199 * @data: the data address 200 * @use_tidal: zero of the data address specifies a contiguous block of data, 201 * non-zero if it specifies a list if tidaws. 202 * 203 * Set the input/output data address of a tcw (depending on the value of the 204 * r-flag and w-flag). If @use_tidal is non-zero, the corresponding tida flag 205 * is set as well. 206 */ 207 void tcw_set_data(struct tcw *tcw, void *data, int use_tidal) 208 { 209 if (tcw->r) { 210 tcw->input = (u64) ((addr_t) data); 211 if (use_tidal) 212 tcw->flags |= TCW_FLAGS_INPUT_TIDA; 213 } else if (tcw->w) { 214 tcw->output = (u64) ((addr_t) data); 215 if (use_tidal) 216 tcw->flags |= TCW_FLAGS_OUTPUT_TIDA; 217 } 218 } 219 EXPORT_SYMBOL(tcw_set_data); 220 221 /** 222 * tcw_set_tccb - set tccb address of a tcw 223 * @tcw: the tcw address 224 * @tccb: the tccb address 225 * 226 * Set the address of the tccb in the specified tcw. 227 */ 228 void tcw_set_tccb(struct tcw *tcw, struct tccb *tccb) 229 { 230 tcw->tccb = (u64) ((addr_t) tccb); 231 } 232 EXPORT_SYMBOL(tcw_set_tccb); 233 234 /** 235 * tcw_set_tsb - set tsb address of a tcw 236 * @tcw: the tcw address 237 * @tsb: the tsb address 238 * 239 * Set the address of the tsb in the specified tcw. 240 */ 241 void tcw_set_tsb(struct tcw *tcw, struct tsb *tsb) 242 { 243 tcw->tsb = (u64) ((addr_t) tsb); 244 } 245 EXPORT_SYMBOL(tcw_set_tsb); 246 247 /** 248 * tccb_init - initialize tccb 249 * @tccb: the tccb address 250 * @size: the maximum size of the tccb 251 * @sac: the service-action-code to be user 252 * 253 * Initialize the header of the specified tccb by resetting all values to zero 254 * and filling in defaults for format, sac and initial tcal fields. 255 */ 256 void tccb_init(struct tccb *tccb, size_t size, u32 sac) 257 { 258 memset(tccb, 0, size); 259 tccb->tcah.format = TCCB_FORMAT_DEFAULT; 260 tccb->tcah.sac = sac; 261 tccb->tcah.tcal = 12; 262 } 263 EXPORT_SYMBOL(tccb_init); 264 265 /** 266 * tsb_init - initialize tsb 267 * @tsb: the tsb address 268 * 269 * Initialize the specified tsb by resetting all values to zero. 270 */ 271 void tsb_init(struct tsb *tsb) 272 { 273 memset(tsb, 0, sizeof(*tsb)); 274 } 275 EXPORT_SYMBOL(tsb_init); 276 277 /** 278 * tccb_add_dcw - add a dcw to the tccb 279 * @tccb: the tccb address 280 * @tccb_size: the maximum tccb size 281 * @cmd: the dcw command 282 * @flags: flags for the dcw 283 * @cd: pointer to control data for this dcw or NULL if none is required 284 * @cd_count: number of control data bytes for this dcw 285 * @count: number of data bytes for this dcw 286 * 287 * Add a new dcw to the specified tccb by writing the dcw information specified 288 * by @cmd, @flags, @cd, @cd_count and @count to the tca of the tccb. Return 289 * a pointer to the newly added dcw on success or -%ENOSPC if the new dcw 290 * would exceed the available space as defined by @tccb_size. 291 * 292 * Note: the tcal field of the tccb header will be updates to reflect added 293 * content. 294 */ 295 struct dcw *tccb_add_dcw(struct tccb *tccb, size_t tccb_size, u8 cmd, u8 flags, 296 void *cd, u8 cd_count, u32 count) 297 { 298 struct dcw *dcw; 299 int size; 300 int tca_offset; 301 302 /* Check for space. */ 303 tca_offset = tca_size(tccb); 304 size = ALIGN(sizeof(struct dcw) + cd_count, 4); 305 if (sizeof(struct tccb_tcah) + tca_offset + size + 306 sizeof(struct tccb_tcat) > tccb_size) 307 return ERR_PTR(-ENOSPC); 308 /* Add dcw to tca. */ 309 dcw = (struct dcw *) &tccb->tca[tca_offset]; 310 memset(dcw, 0, size); 311 dcw->cmd = cmd; 312 dcw->flags = flags; 313 dcw->count = count; 314 dcw->cd_count = cd_count; 315 if (cd) 316 memcpy(&dcw->cd[0], cd, cd_count); 317 tccb->tcah.tcal += size; 318 return dcw; 319 } 320 EXPORT_SYMBOL(tccb_add_dcw); 321 322 /** 323 * tcw_add_tidaw - add a tidaw to a tcw 324 * @tcw: the tcw address 325 * @num_tidaws: the current number of tidaws 326 * @flags: flags for the new tidaw 327 * @addr: address value for the new tidaw 328 * @count: count value for the new tidaw 329 * 330 * Add a new tidaw to the input/output data tidaw-list of the specified tcw 331 * (depending on the value of the r-flag and w-flag) and return a pointer to 332 * the new tidaw. 333 * 334 * Note: the tidaw-list is assumed to be contiguous with no ttics. The caller 335 * must ensure that there is enough space for the new tidaw. The last-tidaw 336 * flag for the last tidaw in the list will be set by tcw_finalize. 337 */ 338 struct tidaw *tcw_add_tidaw(struct tcw *tcw, int num_tidaws, u8 flags, 339 void *addr, u32 count) 340 { 341 struct tidaw *tidaw; 342 343 /* Add tidaw to tidaw-list. */ 344 tidaw = ((struct tidaw *) tcw_get_data(tcw)) + num_tidaws; 345 memset(tidaw, 0, sizeof(struct tidaw)); 346 tidaw->flags = flags; 347 tidaw->count = count; 348 tidaw->addr = (u64) ((addr_t) addr); 349 return tidaw; 350 } 351 EXPORT_SYMBOL(tcw_add_tidaw); 352