arch/s390/pci/pci_clp.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright IBM Corp. 2012
   4  *
   5  * Author(s):
   6  *   Jan Glauber <jang@linux.vnet.ibm.com>
   7  */
   8
   9 #define KMSG_COMPONENT "zpci"
  10 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  11
  12 #include <linux/compat.h>
  13 #include <linux/kernel.h>
  14 #include <linux/miscdevice.h>
  15 #include <linux/slab.h>
  16 #include <linux/err.h>
  17 #include <linux/delay.h>
  18 #include <linux/pci.h>
  19 #include <linux/uaccess.h>
  20 #include <asm/pci_debug.h>
  21 #include <asm/pci_clp.h>
  22 #include <asm/clp.h>
  23 #include <uapi/asm/clp.h>
  24
  25 bool zpci_unique_uid;
  26
  27 static void update_uid_checking(bool new)
  28 {
  29         if (zpci_unique_uid != new)
  30                 zpci_dbg(1, "uid checking:%d\n", new);
  31
  32         zpci_unique_uid = new;
  33 }
  34
  35 static inline void zpci_err_clp(unsigned int rsp, int rc)
  36 {
  37         struct {
  38                 unsigned int rsp;
  39                 int rc;
  40         } __packed data = {rsp, rc};
  41
  42         zpci_err_hex(&data, sizeof(data));
  43 }
  44
  45 /*
  46  * Call Logical Processor with c=1, lps=0 and command 1
  47  * to get the bit mask of installed logical processors
  48  */
  49 static inline int clp_get_ilp(unsigned long *ilp)
  50 {
  51         unsigned long mask;
  52         int cc = 3;
  53
  54         asm volatile (
  55                 "       .insn   rrf,0xb9a00000,%[mask],%[cmd],8,0\n"
  56                 "0:     ipm     %[cc]\n"
  57                 "       srl     %[cc],28\n"
  58                 "1:\n"
  59                 EX_TABLE(0b, 1b)
  60                 : [cc] "+d" (cc), [mask] "=d" (mask) : [cmd] "a" (1)
  61                 : "cc");
  62         *ilp = mask;
  63         return cc;
  64 }
  65
  66 /*
  67  * Call Logical Processor with c=0, the give constant lps and an lpcb request.
  68  */
  69 static __always_inline int clp_req(void *data, unsigned int lps)
  70 {
  71         struct { u8 _[CLP_BLK_SIZE]; } *req = data;
  72         u64 ignored;
  73         int cc = 3;
  74
  75         asm volatile (
  76                 "       .insn   rrf,0xb9a00000,%[ign],%[req],0,%[lps]\n"
  77                 "0:     ipm     %[cc]\n"
  78                 "       srl     %[cc],28\n"
  79                 "1:\n"
  80                 EX_TABLE(0b, 1b)
  81                 : [cc] "+d" (cc), [ign] "=d" (ignored), "+m" (*req)
  82                 : [req] "a" (req), [lps] "i" (lps)
  83                 : "cc");
  84         return cc;
  85 }
  86
  87 static void *clp_alloc_block(gfp_t gfp_mask)
  88 {
  89         return (void *) __get_free_pages(gfp_mask, get_order(CLP_BLK_SIZE));
  90 }
  91
  92 static void clp_free_block(void *ptr)
  93 {
  94         free_pages((unsigned long) ptr, get_order(CLP_BLK_SIZE));
  95 }
  96
  97 static void clp_store_query_pci_fngrp(struct zpci_dev *zdev,
  98                                       struct clp_rsp_query_pci_grp *response)
  99 {
 100         zdev->tlb_refresh = response->refresh;
 101         zdev->dma_mask = response->dasm;
 102         zdev->msi_addr = response->msia;
 103         zdev->max_msi = response->noi;
 104         zdev->fmb_update = response->mui;
 105
 106         switch (response->version) {
 107         case 1:
 108                 zdev->max_bus_speed = PCIE_SPEED_5_0GT;
 109                 break;
 110         default:
 111                 zdev->max_bus_speed = PCI_SPEED_UNKNOWN;
 112                 break;
 113         }
 114 }
 115
 116 static int clp_query_pci_fngrp(struct zpci_dev *zdev, u8 pfgid)
 117 {
 118         struct clp_req_rsp_query_pci_grp *rrb;
 119         int rc;
 120
 121         rrb = clp_alloc_block(GFP_KERNEL);
 122         if (!rrb)
 123                 return -ENOMEM;
 124
 125         memset(rrb, 0, sizeof(*rrb));
 126         rrb->request.hdr.len = sizeof(rrb->request);
 127         rrb->request.hdr.cmd = CLP_QUERY_PCI_FNGRP;
 128         rrb->response.hdr.len = sizeof(rrb->response);
 129         rrb->request.pfgid = pfgid;
 130
 131         rc = clp_req(rrb, CLP_LPS_PCI);
 132         if (!rc && rrb->response.hdr.rsp == CLP_RC_OK)
 133                 clp_store_query_pci_fngrp(zdev, &rrb->response);
 134         else {
 135                 zpci_err("Q PCI FGRP:\n");
 136                 zpci_err_clp(rrb->response.hdr.rsp, rc);
 137                 rc = -EIO;
 138         }
 139         clp_free_block(rrb);
 140         return rc;
 141 }
 142
 143 static int clp_store_query_pci_fn(struct zpci_dev *zdev,
 144                                   struct clp_rsp_query_pci *response)
 145 {
 146         int i;
 147
 148         for (i = 0; i < PCI_STD_NUM_BARS; i++) {
 149                 zdev->bars[i].val = le32_to_cpu(response->bar[i]);
 150                 zdev->bars[i].size = response->bar_size[i];
 151         }
 152         zdev->start_dma = response->sdma;
 153         zdev->end_dma = response->edma;
 154         zdev->pchid = response->pchid;
 155         zdev->pfgid = response->pfgid;
 156         zdev->pft = response->pft;
 157         zdev->vfn = response->vfn;
 158         zdev->uid = response->uid;
 159         zdev->fmb_length = sizeof(u32) * response->fmb_len;
 160
 161         memcpy(zdev->pfip, response->pfip, sizeof(zdev->pfip));
 162         if (response->util_str_avail) {
 163                 memcpy(zdev->util_str, response->util_str,
 164                        sizeof(zdev->util_str));
 165         }
 166         zdev->mio_capable = response->mio_addr_avail;
 167         for (i = 0; i < PCI_STD_NUM_BARS; i++) {
 168                 if (!(response->mio.valid & (1 << (PCI_STD_NUM_BARS - i - 1))))
 169                         continue;
 170
 171                 zdev->bars[i].mio_wb = (void __iomem *) response->mio.addr[i].wb;
 172                 zdev->bars[i].mio_wt = (void __iomem *) response->mio.addr[i].wt;
 173         }
 174         return 0;
 175 }
 176
 177 static int clp_query_pci_fn(struct zpci_dev *zdev, u32 fh)
 178 {
 179         struct clp_req_rsp_query_pci *rrb;
 180         int rc;
 181
 182         rrb = clp_alloc_block(GFP_KERNEL);
 183         if (!rrb)
 184                 return -ENOMEM;
 185
 186         memset(rrb, 0, sizeof(*rrb));
 187         rrb->request.hdr.len = sizeof(rrb->request);
 188         rrb->request.hdr.cmd = CLP_QUERY_PCI_FN;
 189         rrb->response.hdr.len = sizeof(rrb->response);
 190         rrb->request.fh = fh;
 191
 192         rc = clp_req(rrb, CLP_LPS_PCI);
 193         if (!rc && rrb->response.hdr.rsp == CLP_RC_OK) {
 194                 rc = clp_store_query_pci_fn(zdev, &rrb->response);
 195                 if (rc)
 196                         goto out;
 197                 rc = clp_query_pci_fngrp(zdev, rrb->response.pfgid);
 198         } else {
 199                 zpci_err("Q PCI FN:\n");
 200                 zpci_err_clp(rrb->response.hdr.rsp, rc);
 201                 rc = -EIO;
 202         }
 203 out:
 204         clp_free_block(rrb);
 205         return rc;
 206 }
 207
 208 int clp_add_pci_device(u32 fid, u32 fh, int configured)
 209 {
 210         struct zpci_dev *zdev;
 211         int rc = -ENOMEM;
 212
 213         zpci_dbg(3, "add fid:%x, fh:%x, c:%d\n", fid, fh, configured);
 214         zdev = kzalloc(sizeof(*zdev), GFP_KERNEL);
 215         if (!zdev)
 216                 goto error;
 217
 218         zdev->fh = fh;
 219         zdev->fid = fid;
 220
 221         /* Query function properties and update zdev */
 222         rc = clp_query_pci_fn(zdev, fh);
 223         if (rc)
 224                 goto error;
 225
 226         if (configured)
 227                 zdev->state = ZPCI_FN_STATE_CONFIGURED;
 228         else
 229                 zdev->state = ZPCI_FN_STATE_STANDBY;
 230
 231         rc = zpci_create_device(zdev);
 232         if (rc)
 233                 goto error;
 234         return 0;
 235
 236 error:
 237         zpci_dbg(0, "add fid:%x, rc:%d\n", fid, rc);
 238         kfree(zdev);
 239         return rc;
 240 }
 241
 242 /*
 243  * Enable/Disable a given PCI function and update its function handle if
 244  * necessary
 245  */
 246 static int clp_set_pci_fn(struct zpci_dev *zdev, u8 nr_dma_as, u8 command)
 247 {
 248         struct clp_req_rsp_set_pci *rrb;
 249         int rc, retries = 100;
 250         u32 fid = zdev->fid;
 251
 252         rrb = clp_alloc_block(GFP_KERNEL);
 253         if (!rrb)
 254                 return -ENOMEM;
 255
 256         do {
 257                 memset(rrb, 0, sizeof(*rrb));
 258                 rrb->request.hdr.len = sizeof(rrb->request);
 259                 rrb->request.hdr.cmd = CLP_SET_PCI_FN;
 260                 rrb->response.hdr.len = sizeof(rrb->response);
 261                 rrb->request.fh = zdev->fh;
 262                 rrb->request.oc = command;
 263                 rrb->request.ndas = nr_dma_as;
 264
 265                 rc = clp_req(rrb, CLP_LPS_PCI);
 266                 if (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY) {
 267                         retries--;
 268                         if (retries < 0)
 269                                 break;
 270                         msleep(20);
 271                 }
 272         } while (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY);
 273
 274         if (rc || rrb->response.hdr.rsp != CLP_RC_OK) {
 275                 zpci_err("Set PCI FN:\n");
 276                 zpci_err_clp(rrb->response.hdr.rsp, rc);
 277         }
 278
 279         if (!rc && rrb->response.hdr.rsp == CLP_RC_OK) {
 280                 zdev->fh = rrb->response.fh;
 281         } else if (!rc && rrb->response.hdr.rsp == CLP_RC_SETPCIFN_ALRDY &&
 282                         rrb->response.fh == 0) {
 283                 /* Function is already in desired state - update handle */
 284                 rc = clp_rescan_pci_devices_simple(&fid);
 285         }
 286         clp_free_block(rrb);
 287         return rc;
 288 }
 289
 290 int clp_enable_fh(struct zpci_dev *zdev, u8 nr_dma_as)
 291 {
 292         int rc;
 293
 294         rc = clp_set_pci_fn(zdev, nr_dma_as, CLP_SET_ENABLE_PCI_FN);
 295         zpci_dbg(3, "ena fid:%x, fh:%x, rc:%d\n", zdev->fid, zdev->fh, rc);
 296         if (rc)
 297                 goto out;
 298
 299         if (zpci_use_mio(zdev)) {
 300                 rc = clp_set_pci_fn(zdev, nr_dma_as, CLP_SET_ENABLE_MIO);
 301                 zpci_dbg(3, "ena mio fid:%x, fh:%x, rc:%d\n",
 302                                 zdev->fid, zdev->fh, rc);
 303                 if (rc)
 304                         clp_disable_fh(zdev);
 305         }
 306 out:
 307         return rc;
 308 }
 309
 310 int clp_disable_fh(struct zpci_dev *zdev)
 311 {
 312         u32 fh = zdev->fh;
 313         int rc;
 314
 315         if (!zdev_enabled(zdev))
 316                 return 0;
 317
 318         rc = clp_set_pci_fn(zdev, 0, CLP_SET_DISABLE_PCI_FN);
 319         zpci_dbg(3, "dis fid:%x, fh:%x, rc:%d\n", zdev->fid, fh, rc);
 320         return rc;
 321 }
 322
 323 static int clp_list_pci(struct clp_req_rsp_list_pci *rrb, void *data,
 324                         void (*cb)(struct clp_fh_list_entry *, void *))
 325 {
 326         u64 resume_token = 0;
 327         int entries, i, rc;
 328
 329         do {
 330                 memset(rrb, 0, sizeof(*rrb));
 331                 rrb->request.hdr.len = sizeof(rrb->request);
 332                 rrb->request.hdr.cmd = CLP_LIST_PCI;
 333                 /* store as many entries as possible */
 334                 rrb->response.hdr.len = CLP_BLK_SIZE - LIST_PCI_HDR_LEN;
 335                 rrb->request.resume_token = resume_token;
 336
 337                 /* Get PCI function handle list */
 338                 rc = clp_req(rrb, CLP_LPS_PCI);
 339                 if (rc || rrb->response.hdr.rsp != CLP_RC_OK) {
 340                         zpci_err("List PCI FN:\n");
 341                         zpci_err_clp(rrb->response.hdr.rsp, rc);
 342                         rc = -EIO;
 343                         goto out;
 344                 }
 345
 346                 update_uid_checking(rrb->response.uid_checking);
 347                 WARN_ON_ONCE(rrb->response.entry_size !=
 348                         sizeof(struct clp_fh_list_entry));
 349
 350                 entries = (rrb->response.hdr.len - LIST_PCI_HDR_LEN) /
 351                         rrb->response.entry_size;
 352
 353                 resume_token = rrb->response.resume_token;
 354                 for (i = 0; i < entries; i++)
 355                         cb(&rrb->response.fh_list[i], data);
 356         } while (resume_token);
 357 out:
 358         return rc;
 359 }
 360
 361 static void __clp_add(struct clp_fh_list_entry *entry, void *data)
 362 {
 363         struct zpci_dev *zdev;
 364
 365         if (!entry->vendor_id)
 366                 return;
 367
 368         zdev = get_zdev_by_fid(entry->fid);
 369         if (!zdev)
 370                 clp_add_pci_device(entry->fid, entry->fh, entry->config_state);
 371 }
 372
 373 static void __clp_update(struct clp_fh_list_entry *entry, void *data)
 374 {
 375         struct zpci_dev *zdev;
 376         u32 *fid = data;
 377
 378         if (!entry->vendor_id)
 379                 return;
 380
 381         if (fid && *fid != entry->fid)
 382                 return;
 383
 384         zdev = get_zdev_by_fid(entry->fid);
 385         if (!zdev)
 386                 return;
 387
 388         zdev->fh = entry->fh;
 389 }
 390
 391 int clp_scan_pci_devices(void)
 392 {
 393         struct clp_req_rsp_list_pci *rrb;
 394         int rc;
 395
 396         rrb = clp_alloc_block(GFP_KERNEL);
 397         if (!rrb)
 398                 return -ENOMEM;
 399
 400         rc = clp_list_pci(rrb, NULL, __clp_add);
 401
 402         clp_free_block(rrb);
 403         return rc;
 404 }
 405
 406 int clp_rescan_pci_devices(void)
 407 {
 408         struct clp_req_rsp_list_pci *rrb;
 409         int rc;
 410
 411         zpci_remove_reserved_devices();
 412
 413         rrb = clp_alloc_block(GFP_KERNEL);
 414         if (!rrb)
 415                 return -ENOMEM;
 416
 417         rc = clp_list_pci(rrb, NULL, __clp_add);
 418
 419         clp_free_block(rrb);
 420         return rc;
 421 }
 422
 423 /* Rescan PCI functions and refresh function handles. If fid is non-NULL only
 424  * refresh the handle of the function matching @fid
 425  */
 426 int clp_rescan_pci_devices_simple(u32 *fid)
 427 {
 428         struct clp_req_rsp_list_pci *rrb;
 429         int rc;
 430
 431         rrb = clp_alloc_block(GFP_NOWAIT);
 432         if (!rrb)
 433                 return -ENOMEM;
 434
 435         rc = clp_list_pci(rrb, fid, __clp_update);
 436
 437         clp_free_block(rrb);
 438         return rc;
 439 }
 440
 441 struct clp_state_data {
 442         u32 fid;
 443         enum zpci_state state;
 444 };
 445
 446 static void __clp_get_state(struct clp_fh_list_entry *entry, void *data)
 447 {
 448         struct clp_state_data *sd = data;
 449
 450         if (entry->fid != sd->fid)
 451                 return;
 452
 453         sd->state = entry->config_state;
 454 }
 455
 456 int clp_get_state(u32 fid, enum zpci_state *state)
 457 {
 458         struct clp_req_rsp_list_pci *rrb;
 459         struct clp_state_data sd = {fid, ZPCI_FN_STATE_RESERVED};
 460         int rc;
 461
 462         rrb = clp_alloc_block(GFP_ATOMIC);
 463         if (!rrb)
 464                 return -ENOMEM;
 465
 466         rc = clp_list_pci(rrb, &sd, __clp_get_state);
 467         if (!rc)
 468                 *state = sd.state;
 469
 470         clp_free_block(rrb);
 471         return rc;
 472 }
 473
 474 static int clp_base_slpc(struct clp_req *req, struct clp_req_rsp_slpc *lpcb)
 475 {
 476         unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
 477
 478         if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
 479             lpcb->response.hdr.len > limit)
 480                 return -EINVAL;
 481         return clp_req(lpcb, CLP_LPS_BASE) ? -EOPNOTSUPP : 0;
 482 }
 483
 484 static int clp_base_command(struct clp_req *req, struct clp_req_hdr *lpcb)
 485 {
 486         switch (lpcb->cmd) {
 487         case 0x0001: /* store logical-processor characteristics */
 488                 return clp_base_slpc(req, (void *) lpcb);
 489         default:
 490                 return -EINVAL;
 491         }
 492 }
 493
 494 static int clp_pci_slpc(struct clp_req *req, struct clp_req_rsp_slpc *lpcb)
 495 {
 496         unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
 497
 498         if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
 499             lpcb->response.hdr.len > limit)
 500                 return -EINVAL;
 501         return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
 502 }
 503
 504 static int clp_pci_list(struct clp_req *req, struct clp_req_rsp_list_pci *lpcb)
 505 {
 506         unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
 507
 508         if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
 509             lpcb->response.hdr.len > limit)
 510                 return -EINVAL;
 511         if (lpcb->request.reserved2 != 0)
 512                 return -EINVAL;
 513         return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
 514 }
 515
 516 static int clp_pci_query(struct clp_req *req,
 517                          struct clp_req_rsp_query_pci *lpcb)
 518 {
 519         unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
 520
 521         if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
 522             lpcb->response.hdr.len > limit)
 523                 return -EINVAL;
 524         if (lpcb->request.reserved2 != 0 || lpcb->request.reserved3 != 0)
 525                 return -EINVAL;
 526         return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
 527 }
 528
 529 static int clp_pci_query_grp(struct clp_req *req,
 530                              struct clp_req_rsp_query_pci_grp *lpcb)
 531 {
 532         unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
 533
 534         if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
 535             lpcb->response.hdr.len > limit)
 536                 return -EINVAL;
 537         if (lpcb->request.reserved2 != 0 || lpcb->request.reserved3 != 0 ||
 538             lpcb->request.reserved4 != 0)
 539                 return -EINVAL;
 540         return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
 541 }
 542
 543 static int clp_pci_command(struct clp_req *req, struct clp_req_hdr *lpcb)
 544 {
 545         switch (lpcb->cmd) {
 546         case 0x0001: /* store logical-processor characteristics */
 547                 return clp_pci_slpc(req, (void *) lpcb);
 548         case 0x0002: /* list PCI functions */
 549                 return clp_pci_list(req, (void *) lpcb);
 550         case 0x0003: /* query PCI function */
 551                 return clp_pci_query(req, (void *) lpcb);
 552         case 0x0004: /* query PCI function group */
 553                 return clp_pci_query_grp(req, (void *) lpcb);
 554         default:
 555                 return -EINVAL;
 556         }
 557 }
 558
 559 static int clp_normal_command(struct clp_req *req)
 560 {
 561         struct clp_req_hdr *lpcb;
 562         void __user *uptr;
 563         int rc;
 564
 565         rc = -EINVAL;
 566         if (req->lps != 0 && req->lps != 2)
 567                 goto out;
 568
 569         rc = -ENOMEM;
 570         lpcb = clp_alloc_block(GFP_KERNEL);
 571         if (!lpcb)
 572                 goto out;
 573
 574         rc = -EFAULT;
 575         uptr = (void __force __user *)(unsigned long) req->data_p;
 576         if (copy_from_user(lpcb, uptr, PAGE_SIZE) != 0)
 577                 goto out_free;
 578
 579         rc = -EINVAL;
 580         if (lpcb->fmt != 0 || lpcb->reserved1 != 0 || lpcb->reserved2 != 0)
 581                 goto out_free;
 582
 583         switch (req->lps) {
 584         case 0:
 585                 rc = clp_base_command(req, lpcb);
 586                 break;
 587         case 2:
 588                 rc = clp_pci_command(req, lpcb);
 589                 break;
 590         }
 591         if (rc)
 592                 goto out_free;
 593
 594         rc = -EFAULT;
 595         if (copy_to_user(uptr, lpcb, PAGE_SIZE) != 0)
 596                 goto out_free;
 597
 598         rc = 0;
 599
 600 out_free:
 601         clp_free_block(lpcb);
 602 out:
 603         return rc;
 604 }
 605
 606 static int clp_immediate_command(struct clp_req *req)
 607 {
 608         void __user *uptr;
 609         unsigned long ilp;
 610         int exists;
 611
 612         if (req->cmd > 1 || clp_get_ilp(&ilp) != 0)
 613                 return -EINVAL;
 614
 615         uptr = (void __force __user *)(unsigned long) req->data_p;
 616         if (req->cmd == 0) {
 617                 /* Command code 0: test for a specific processor */
 618                 exists = test_bit_inv(req->lps, &ilp);
 619                 return put_user(exists, (int __user *) uptr);
 620         }
 621         /* Command code 1: return bit mask of installed processors */
 622         return put_user(ilp, (unsigned long __user *) uptr);
 623 }
 624
 625 static long clp_misc_ioctl(struct file *filp, unsigned int cmd,
 626                            unsigned long arg)
 627 {
 628         struct clp_req req;
 629         void __user *argp;
 630
 631         if (cmd != CLP_SYNC)
 632                 return -EINVAL;
 633
 634         argp = is_compat_task() ? compat_ptr(arg) : (void __user *) arg;
 635         if (copy_from_user(&req, argp, sizeof(req)))
 636                 return -EFAULT;
 637         if (req.r != 0)
 638                 return -EINVAL;
 639         return req.c ? clp_immediate_command(&req) : clp_normal_command(&req);
 640 }
 641
 642 static int clp_misc_release(struct inode *inode, struct file *filp)
 643 {
 644         return 0;
 645 }
 646
 647 static const struct file_operations clp_misc_fops = {
 648         .owner = THIS_MODULE,
 649         .open = nonseekable_open,
 650         .release = clp_misc_release,
 651         .unlocked_ioctl = clp_misc_ioctl,
 652         .compat_ioctl = clp_misc_ioctl,
 653         .llseek = no_llseek,
 654 };
 655
 656 static struct miscdevice clp_misc_device = {
 657         .minor = MISC_DYNAMIC_MINOR,
 658         .name = "clp",
 659         .fops = &clp_misc_fops,
 660 };
 661
 662 static int __init clp_misc_init(void)
 663 {
 664         return misc_register(&clp_misc_device);
 665 }
 666
 667 device_initcall(clp_misc_init);