SAFE public projects git trees. - safe/jmp/linux-2.6/blob - drivers/scsi/osd/osd_initiator.c

   1 /*
   2  * osd_initiator - Main body of the osd initiator library.
   3  *
   4  * Note: The file does not contain the advanced security functionality which
   5  * is only needed by the security_manager's initiators.
   6  *
   7  * Copyright (C) 2008 Panasas Inc.  All rights reserved.
   8  *
   9  * Authors:
  10  *   Boaz Harrosh <bharrosh@panasas.com>
  11  *   Benny Halevy <bhalevy@panasas.com>
  12  *
  13  * This program is free software; you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License version 2
  15  *
  16  * Redistribution and use in source and binary forms, with or without
  17  * modification, are permitted provided that the following conditions
  18  * are met:
  19  *
  20  *  1. Redistributions of source code must retain the above copyright
  21  *     notice, this list of conditions and the following disclaimer.
  22  *  2. Redistributions in binary form must reproduce the above copyright
  23  *     notice, this list of conditions and the following disclaimer in the
  24  *     documentation and/or other materials provided with the distribution.
  25  *  3. Neither the name of the Panasas company nor the names of its
  26  *     contributors may be used to endorse or promote products derived
  27  *     from this software without specific prior written permission.
  28  *
  29  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
  30  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  31  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  32  * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  33  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  34  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  35  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  36  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  37  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  38  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  39  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  40  */
  41
  42 #include <scsi/osd_initiator.h>
  43 #include <scsi/osd_sec.h>
  44 #include <scsi/osd_attributes.h>
  45 #include <scsi/osd_sense.h>
  46
  47 #include <scsi/scsi_device.h>
  48
  49 #include "osd_debug.h"
  50
  51 #ifndef __unused
  52 #    define __unused                    __attribute__((unused))
  53 #endif
  54
  55 enum { OSD_REQ_RETRIES = 1 };
  56
  57 MODULE_AUTHOR("Boaz Harrosh <bharrosh@panasas.com>");
  58 MODULE_DESCRIPTION("open-osd initiator library libosd.ko");
  59 MODULE_LICENSE("GPL");
  60
  61 static inline void build_test(void)
  62 {
  63         /* structures were not packed */
  64         BUILD_BUG_ON(sizeof(struct osd_capability) != OSD_CAP_LEN);
  65         BUILD_BUG_ON(sizeof(struct osdv2_cdb) != OSD_TOTAL_CDB_LEN);
  66         BUILD_BUG_ON(sizeof(struct osdv1_cdb) != OSDv1_TOTAL_CDB_LEN);
  67 }
  68
  69 static const char *_osd_ver_desc(struct osd_request *or)
  70 {
  71         return osd_req_is_ver1(or) ? "OSD1" : "OSD2";
  72 }
  73
  74 #define ATTR_DEF_RI(id, len) ATTR_DEF(OSD_APAGE_ROOT_INFORMATION, id, len)
  75
  76 static int _osd_get_print_system_info(struct osd_dev *od,
  77         void *caps, struct osd_dev_info *odi)
  78 {
  79         struct osd_request *or;
  80         struct osd_attr get_attrs[] = {
  81                 ATTR_DEF_RI(OSD_ATTR_RI_VENDOR_IDENTIFICATION, 8),
  82                 ATTR_DEF_RI(OSD_ATTR_RI_PRODUCT_IDENTIFICATION, 16),
  83                 ATTR_DEF_RI(OSD_ATTR_RI_PRODUCT_MODEL, 32),
  84                 ATTR_DEF_RI(OSD_ATTR_RI_PRODUCT_REVISION_LEVEL, 4),
  85                 ATTR_DEF_RI(OSD_ATTR_RI_PRODUCT_SERIAL_NUMBER, 64 /*variable*/),
  86                 ATTR_DEF_RI(OSD_ATTR_RI_OSD_NAME, 64 /*variable*/),
  87                 ATTR_DEF_RI(OSD_ATTR_RI_TOTAL_CAPACITY, 8),
  88                 ATTR_DEF_RI(OSD_ATTR_RI_USED_CAPACITY, 8),
  89                 ATTR_DEF_RI(OSD_ATTR_RI_NUMBER_OF_PARTITIONS, 8),
  90                 ATTR_DEF_RI(OSD_ATTR_RI_CLOCK, 6),
  91                 /* IBM-OSD-SIM Has a bug with this one put it last */
  92                 ATTR_DEF_RI(OSD_ATTR_RI_OSD_SYSTEM_ID, 20),
  93         };
  94         void *iter = NULL, *pFirst;
  95         int nelem = ARRAY_SIZE(get_attrs), a = 0;
  96         int ret;
  97
  98         or = osd_start_request(od, GFP_KERNEL);
  99         if (!or)
 100                 return -ENOMEM;
 101
 102         /* get attrs */
 103         osd_req_get_attributes(or, &osd_root_object);
 104         osd_req_add_get_attr_list(or, get_attrs, ARRAY_SIZE(get_attrs));
 105
 106         ret = osd_finalize_request(or, 0, caps, NULL);
 107         if (ret)
 108                 goto out;
 109
 110         ret = osd_execute_request(or);
 111         if (ret) {
 112                 OSD_ERR("Failed to detect %s => %d\n", _osd_ver_desc(or), ret);
 113                 goto out;
 114         }
 115
 116         osd_req_decode_get_attr_list(or, get_attrs, &nelem, &iter);
 117
 118         OSD_INFO("Detected %s device\n",
 119                 _osd_ver_desc(or));
 120
 121         pFirst = get_attrs[a++].val_ptr;
 122         OSD_INFO("VENDOR_IDENTIFICATION  [%s]\n",
 123                 (char *)pFirst);
 124
 125         pFirst = get_attrs[a++].val_ptr;
 126         OSD_INFO("PRODUCT_IDENTIFICATION [%s]\n",
 127                 (char *)pFirst);
 128
 129         pFirst = get_attrs[a++].val_ptr;
 130         OSD_INFO("PRODUCT_MODEL          [%s]\n",
 131                 (char *)pFirst);
 132
 133         pFirst = get_attrs[a++].val_ptr;
 134         OSD_INFO("PRODUCT_REVISION_LEVEL [%u]\n",
 135                 pFirst ? get_unaligned_be32(pFirst) : ~0U);
 136
 137         pFirst = get_attrs[a++].val_ptr;
 138         OSD_INFO("PRODUCT_SERIAL_NUMBER  [%s]\n",
 139                 (char *)pFirst);
 140
 141         odi->osdname_len = get_attrs[a].len;
 142         /* Avoid NULL for memcmp optimization 0-length is good enough */
 143         odi->osdname = kzalloc(odi->osdname_len + 1, GFP_KERNEL);
 144         if (odi->osdname_len)
 145                 memcpy(odi->osdname, get_attrs[a].val_ptr, odi->osdname_len);
 146         OSD_INFO("OSD_NAME               [%s]\n", odi->osdname);
 147         a++;
 148
 149         pFirst = get_attrs[a++].val_ptr;
 150         OSD_INFO("TOTAL_CAPACITY         [0x%llx]\n",
 151                 pFirst ? _LLU(get_unaligned_be64(pFirst)) : ~0ULL);
 152
 153         pFirst = get_attrs[a++].val_ptr;
 154         OSD_INFO("USED_CAPACITY          [0x%llx]\n",
 155                 pFirst ? _LLU(get_unaligned_be64(pFirst)) : ~0ULL);
 156
 157         pFirst = get_attrs[a++].val_ptr;
 158         OSD_INFO("NUMBER_OF_PARTITIONS   [%llu]\n",
 159                 pFirst ? _LLU(get_unaligned_be64(pFirst)) : ~0ULL);
 160
 161         if (a >= nelem)
 162                 goto out;
 163
 164         /* FIXME: Where are the time utilities */
 165         pFirst = get_attrs[a++].val_ptr;
 166         OSD_INFO("CLOCK                  [0x%02x%02x%02x%02x%02x%02x]\n",
 167                 ((char *)pFirst)[0], ((char *)pFirst)[1],
 168                 ((char *)pFirst)[2], ((char *)pFirst)[3],
 169                 ((char *)pFirst)[4], ((char *)pFirst)[5]);
 170
 171         if (a < nelem) { /* IBM-OSD-SIM bug, Might not have it */
 172                 unsigned len = get_attrs[a].len;
 173                 char sid_dump[32*4 + 2]; /* 2nibbles+space+ASCII */
 174
 175                 hex_dump_to_buffer(get_attrs[a].val_ptr, len, 32, 1,
 176                                    sid_dump, sizeof(sid_dump), true);
 177                 OSD_INFO("OSD_SYSTEM_ID(%d)\n"
 178                          "        [%s]\n", len, sid_dump);
 179
 180                 if (unlikely(len > sizeof(odi->systemid))) {
 181                         OSD_ERR("OSD Target error: OSD_SYSTEM_ID too long(%d). "
 182                                 "device idetification might not work\n", len);
 183                         len = sizeof(odi->systemid);
 184                 }
 185                 odi->systemid_len = len;
 186                 memcpy(odi->systemid, get_attrs[a].val_ptr, len);
 187                 a++;
 188         }
 189 out:
 190         osd_end_request(or);
 191         return ret;
 192 }
 193
 194 int osd_auto_detect_ver(struct osd_dev *od,
 195         void *caps, struct osd_dev_info *odi)
 196 {
 197         int ret;
 198
 199         /* Auto-detect the osd version */
 200         ret = _osd_get_print_system_info(od, caps, odi);
 201         if (ret) {
 202                 osd_dev_set_ver(od, OSD_VER1);
 203                 OSD_DEBUG("converting to OSD1\n");
 204                 ret = _osd_get_print_system_info(od, caps, odi);
 205         }
 206
 207         return ret;
 208 }
 209 EXPORT_SYMBOL(osd_auto_detect_ver);
 210
 211 static unsigned _osd_req_cdb_len(struct osd_request *or)
 212 {
 213         return osd_req_is_ver1(or) ? OSDv1_TOTAL_CDB_LEN : OSD_TOTAL_CDB_LEN;
 214 }
 215
 216 static unsigned _osd_req_alist_elem_size(struct osd_request *or, unsigned len)
 217 {
 218         return osd_req_is_ver1(or) ?
 219                 osdv1_attr_list_elem_size(len) :
 220                 osdv2_attr_list_elem_size(len);
 221 }
 222
 223 static void _osd_req_alist_elem_encode(struct osd_request *or,
 224         void *attr_last, const struct osd_attr *oa)
 225 {
 226         if (osd_req_is_ver1(or)) {
 227                 struct osdv1_attributes_list_element *attr = attr_last;
 228
 229                 attr->attr_page = cpu_to_be32(oa->attr_page);
 230                 attr->attr_id = cpu_to_be32(oa->attr_id);
 231                 attr->attr_bytes = cpu_to_be16(oa->len);
 232                 memcpy(attr->attr_val, oa->val_ptr, oa->len);
 233         } else {
 234                 struct osdv2_attributes_list_element *attr = attr_last;
 235
 236                 attr->attr_page = cpu_to_be32(oa->attr_page);
 237                 attr->attr_id = cpu_to_be32(oa->attr_id);
 238                 attr->attr_bytes = cpu_to_be16(oa->len);
 239                 memcpy(attr->attr_val, oa->val_ptr, oa->len);
 240         }
 241 }
 242
 243 static int _osd_req_alist_elem_decode(struct osd_request *or,
 244         void *cur_p, struct osd_attr *oa, unsigned max_bytes)
 245 {
 246         unsigned inc;
 247         if (osd_req_is_ver1(or)) {
 248                 struct osdv1_attributes_list_element *attr = cur_p;
 249
 250                 if (max_bytes < sizeof(*attr))
 251                         return -1;
 252
 253                 oa->len = be16_to_cpu(attr->attr_bytes);
 254                 inc = _osd_req_alist_elem_size(or, oa->len);
 255                 if (inc > max_bytes)
 256                         return -1;
 257
 258                 oa->attr_page = be32_to_cpu(attr->attr_page);
 259                 oa->attr_id = be32_to_cpu(attr->attr_id);
 260
 261                 /* OSD1: On empty attributes we return a pointer to 2 bytes
 262                  * of zeros. This keeps similar behaviour with OSD2.
 263                  * (See below)
 264                  */
 265                 oa->val_ptr = likely(oa->len) ? attr->attr_val :
 266                                                 (u8 *)&attr->attr_bytes;
 267         } else {
 268                 struct osdv2_attributes_list_element *attr = cur_p;
 269
 270                 if (max_bytes < sizeof(*attr))
 271                         return -1;
 272
 273                 oa->len = be16_to_cpu(attr->attr_bytes);
 274                 inc = _osd_req_alist_elem_size(or, oa->len);
 275                 if (inc > max_bytes)
 276                         return -1;
 277
 278                 oa->attr_page = be32_to_cpu(attr->attr_page);
 279                 oa->attr_id = be32_to_cpu(attr->attr_id);
 280
 281                 /* OSD2: For convenience, on empty attributes, we return 8 bytes
 282                  * of zeros here. This keeps the same behaviour with OSD2r04,
 283                  * and is nice with null terminating ASCII fields.
 284                  * oa->val_ptr == NULL marks the end-of-list, or error.
 285                  */
 286                 oa->val_ptr = likely(oa->len) ? attr->attr_val : attr->reserved;
 287         }
 288         return inc;
 289 }
 290
 291 static unsigned _osd_req_alist_size(struct osd_request *or, void *list_head)
 292 {
 293         return osd_req_is_ver1(or) ?
 294                 osdv1_list_size(list_head) :
 295                 osdv2_list_size(list_head);
 296 }
 297
 298 static unsigned _osd_req_sizeof_alist_header(struct osd_request *or)
 299 {
 300         return osd_req_is_ver1(or) ?
 301                 sizeof(struct osdv1_attributes_list_header) :
 302                 sizeof(struct osdv2_attributes_list_header);
 303 }
 304
 305 static void _osd_req_set_alist_type(struct osd_request *or,
 306         void *list, int list_type)
 307 {
 308         if (osd_req_is_ver1(or)) {
 309                 struct osdv1_attributes_list_header *attr_list = list;
 310
 311                 memset(attr_list, 0, sizeof(*attr_list));
 312                 attr_list->type = list_type;
 313         } else {
 314                 struct osdv2_attributes_list_header *attr_list = list;
 315
 316                 memset(attr_list, 0, sizeof(*attr_list));
 317                 attr_list->type = list_type;
 318         }
 319 }
 320
 321 static bool _osd_req_is_alist_type(struct osd_request *or,
 322         void *list, int list_type)
 323 {
 324         if (!list)
 325                 return false;
 326
 327         if (osd_req_is_ver1(or)) {
 328                 struct osdv1_attributes_list_header *attr_list = list;
 329
 330                 return attr_list->type == list_type;
 331         } else {
 332                 struct osdv2_attributes_list_header *attr_list = list;
 333
 334                 return attr_list->type == list_type;
 335         }
 336 }
 337
 338 /* This is for List-objects not Attributes-Lists */
 339 static void _osd_req_encode_olist(struct osd_request *or,
 340         struct osd_obj_id_list *list)
 341 {
 342         struct osd_cdb_head *cdbh = osd_cdb_head(&or->cdb);
 343
 344         if (osd_req_is_ver1(or)) {
 345                 cdbh->v1.list_identifier = list->list_identifier;
 346                 cdbh->v1.start_address = list->continuation_id;
 347         } else {
 348                 cdbh->v2.list_identifier = list->list_identifier;
 349                 cdbh->v2.start_address = list->continuation_id;
 350         }
 351 }
 352
 353 static osd_cdb_offset osd_req_encode_offset(struct osd_request *or,
 354         u64 offset, unsigned *padding)
 355 {
 356         return __osd_encode_offset(offset, padding,
 357                         osd_req_is_ver1(or) ?
 358                                 OSDv1_OFFSET_MIN_SHIFT : OSD_OFFSET_MIN_SHIFT,
 359                         OSD_OFFSET_MAX_SHIFT);
 360 }
 361
 362 static struct osd_security_parameters *
 363 _osd_req_sec_params(struct osd_request *or)
 364 {
 365         struct osd_cdb *ocdb = &or->cdb;
 366
 367         if (osd_req_is_ver1(or))
 368                 return (struct osd_security_parameters *)&ocdb->v1.sec_params;
 369         else
 370                 return (struct osd_security_parameters *)&ocdb->v2.sec_params;
 371 }
 372
 373 void osd_dev_init(struct osd_dev *osdd, struct scsi_device *scsi_device)
 374 {
 375         memset(osdd, 0, sizeof(*osdd));
 376         osdd->scsi_device = scsi_device;
 377         osdd->def_timeout = BLK_DEFAULT_SG_TIMEOUT;
 378 #ifdef OSD_VER1_SUPPORT
 379         osdd->version = OSD_VER2;
 380 #endif
 381         /* TODO: Allocate pools for osd_request attributes ... */
 382 }
 383 EXPORT_SYMBOL(osd_dev_init);
 384
 385 void osd_dev_fini(struct osd_dev *osdd)
 386 {
 387         /* TODO: De-allocate pools */
 388
 389         osdd->scsi_device = NULL;
 390 }
 391 EXPORT_SYMBOL(osd_dev_fini);
 392
 393 static struct osd_request *_osd_request_alloc(gfp_t gfp)
 394 {
 395         struct osd_request *or;
 396
 397         /* TODO: Use mempool with one saved request */
 398         or = kzalloc(sizeof(*or), gfp);
 399         return or;
 400 }
 401
 402 static void _osd_request_free(struct osd_request *or)
 403 {
 404         kfree(or);
 405 }
 406
 407 struct osd_request *osd_start_request(struct osd_dev *dev, gfp_t gfp)
 408 {
 409         struct osd_request *or;
 410
 411         or = _osd_request_alloc(gfp);
 412         if (!or)
 413                 return NULL;
 414
 415         or->osd_dev = dev;
 416         or->alloc_flags = gfp;
 417         or->timeout = dev->def_timeout;
 418         or->retries = OSD_REQ_RETRIES;
 419
 420         return or;
 421 }
 422 EXPORT_SYMBOL(osd_start_request);
 423
 424 static void _osd_free_seg(struct osd_request *or __unused,
 425         struct _osd_req_data_segment *seg)
 426 {
 427         if (!seg->buff || !seg->alloc_size)
 428                 return;
 429
 430         kfree(seg->buff);
 431         seg->buff = NULL;
 432         seg->alloc_size = 0;
 433 }
 434
 435 static void _put_request(struct request *rq , bool is_async)
 436 {
 437         if (is_async) {
 438                 WARN_ON(rq->bio);
 439                 __blk_put_request(rq->q, rq);
 440         } else {
 441                 /*
 442                  * If osd_finalize_request() was called but the request was not
 443                  * executed through the block layer, then we must release BIOs.
 444                  * TODO: Keep error code in or->async_error. Need to audit all
 445                  *       code paths.
 446                  */
 447                 if (unlikely(rq->bio))
 448                         blk_end_request(rq, -ENOMEM, blk_rq_bytes(rq));
 449                 else
 450                         blk_put_request(rq);
 451         }
 452 }
 453
 454 void osd_end_request(struct osd_request *or)
 455 {
 456         struct request *rq = or->request;
 457         /* IMPORTANT: make sure this agrees with osd_execute_request_async */
 458         bool is_async = (or->request->end_io_data == or);
 459
 460         _osd_free_seg(or, &or->set_attr);
 461         _osd_free_seg(or, &or->enc_get_attr);
 462         _osd_free_seg(or, &or->get_attr);
 463
 464         if (rq) {
 465                 if (rq->next_rq) {
 466                         _put_request(rq->next_rq, is_async);
 467                         rq->next_rq = NULL;
 468                 }
 469
 470                 _put_request(rq, is_async);
 471         }
 472         _osd_request_free(or);
 473 }
 474 EXPORT_SYMBOL(osd_end_request);
 475
 476 int osd_execute_request(struct osd_request *or)
 477 {
 478         return blk_execute_rq(or->request->q, NULL, or->request, 0);
 479 }
 480 EXPORT_SYMBOL(osd_execute_request);
 481
 482 static void osd_request_async_done(struct request *req, int error)
 483 {
 484         struct osd_request *or = req->end_io_data;
 485
 486         or->async_error = error;
 487
 488         if (error)
 489                 OSD_DEBUG("osd_request_async_done error recieved %d\n", error);
 490
 491         if (or->async_done)
 492                 or->async_done(or, or->async_private);
 493         else
 494                 osd_end_request(or);
 495 }
 496
 497 int osd_execute_request_async(struct osd_request *or,
 498         osd_req_done_fn *done, void *private)
 499 {
 500         or->request->end_io_data = or;
 501         or->async_private = private;
 502         or->async_done = done;
 503
 504         blk_execute_rq_nowait(or->request->q, NULL, or->request, 0,
 505                               osd_request_async_done);
 506         return 0;
 507 }
 508 EXPORT_SYMBOL(osd_execute_request_async);
 509
 510 u8 sg_out_pad_buffer[1 << OSDv1_OFFSET_MIN_SHIFT];
 511 u8 sg_in_pad_buffer[1 << OSDv1_OFFSET_MIN_SHIFT];
 512
 513 static int _osd_realloc_seg(struct osd_request *or,
 514         struct _osd_req_data_segment *seg, unsigned max_bytes)
 515 {
 516         void *buff;
 517
 518         if (seg->alloc_size >= max_bytes)
 519                 return 0;
 520
 521         buff = krealloc(seg->buff, max_bytes, or->alloc_flags);
 522         if (!buff) {
 523                 OSD_ERR("Failed to Realloc %d-bytes was-%d\n", max_bytes,
 524                         seg->alloc_size);
 525                 return -ENOMEM;
 526         }
 527
 528         memset(buff + seg->alloc_size, 0, max_bytes - seg->alloc_size);
 529         seg->buff = buff;
 530         seg->alloc_size = max_bytes;
 531         return 0;
 532 }
 533
 534 static int _alloc_set_attr_list(struct osd_request *or,
 535         const struct osd_attr *oa, unsigned nelem, unsigned add_bytes)
 536 {
 537         unsigned total_bytes = add_bytes;
 538
 539         for (; nelem; --nelem, ++oa)
 540                 total_bytes += _osd_req_alist_elem_size(or, oa->len);
 541
 542         OSD_DEBUG("total_bytes=%d\n", total_bytes);
 543         return _osd_realloc_seg(or, &or->set_attr, total_bytes);
 544 }
 545
 546 static int _alloc_get_attr_desc(struct osd_request *or, unsigned max_bytes)
 547 {
 548         OSD_DEBUG("total_bytes=%d\n", max_bytes);
 549         return _osd_realloc_seg(or, &or->enc_get_attr, max_bytes);
 550 }
 551
 552 static int _alloc_get_attr_list(struct osd_request *or)
 553 {
 554         OSD_DEBUG("total_bytes=%d\n", or->get_attr.total_bytes);
 555         return _osd_realloc_seg(or, &or->get_attr, or->get_attr.total_bytes);
 556 }
 557
 558 /*
 559  * Common to all OSD commands
 560  */
 561
 562 static void _osdv1_req_encode_common(struct osd_request *or,
 563         __be16 act, const struct osd_obj_id *obj, u64 offset, u64 len)
 564 {
 565         struct osdv1_cdb *ocdb = &or->cdb.v1;
 566
 567         /*
 568          * For speed, the commands
 569          *      OSD_ACT_PERFORM_SCSI_COMMAND    , V1 0x8F7E, V2 0x8F7C
 570          *      OSD_ACT_SCSI_TASK_MANAGEMENT    , V1 0x8F7F, V2 0x8F7D
 571          * are not supported here. Should pass zero and set after the call
 572          */
 573         act &= cpu_to_be16(~0x0080); /* V1 action code */
 574
 575         OSD_DEBUG("OSDv1 execute opcode 0x%x\n", be16_to_cpu(act));
 576
 577         ocdb->h.varlen_cdb.opcode = VARIABLE_LENGTH_CMD;
 578         ocdb->h.varlen_cdb.additional_cdb_length = OSD_ADDITIONAL_CDB_LENGTH;
 579         ocdb->h.varlen_cdb.service_action = act;
 580
 581         ocdb->h.partition = cpu_to_be64(obj->partition);
 582         ocdb->h.object = cpu_to_be64(obj->id);
 583         ocdb->h.v1.length = cpu_to_be64(len);
 584         ocdb->h.v1.start_address = cpu_to_be64(offset);
 585 }
 586
 587 static void _osdv2_req_encode_common(struct osd_request *or,
 588          __be16 act, const struct osd_obj_id *obj, u64 offset, u64 len)
 589 {
 590         struct osdv2_cdb *ocdb = &or->cdb.v2;
 591
 592         OSD_DEBUG("OSDv2 execute opcode 0x%x\n", be16_to_cpu(act));
 593
 594         ocdb->h.varlen_cdb.opcode = VARIABLE_LENGTH_CMD;
 595         ocdb->h.varlen_cdb.additional_cdb_length = OSD_ADDITIONAL_CDB_LENGTH;
 596         ocdb->h.varlen_cdb.service_action = act;
 597
 598         ocdb->h.partition = cpu_to_be64(obj->partition);
 599         ocdb->h.object = cpu_to_be64(obj->id);
 600         ocdb->h.v2.length = cpu_to_be64(len);
 601         ocdb->h.v2.start_address = cpu_to_be64(offset);
 602 }
 603
 604 static void _osd_req_encode_common(struct osd_request *or,
 605         __be16 act, const struct osd_obj_id *obj, u64 offset, u64 len)
 606 {
 607         if (osd_req_is_ver1(or))
 608                 _osdv1_req_encode_common(or, act, obj, offset, len);
 609         else
 610                 _osdv2_req_encode_common(or, act, obj, offset, len);
 611 }
 612
 613 /*
 614  * Device commands
 615  */
 616 /*TODO: void osd_req_set_master_seed_xchg(struct osd_request *, ...); */
 617 /*TODO: void osd_req_set_master_key(struct osd_request *, ...); */
 618
 619 void osd_req_format(struct osd_request *or, u64 tot_capacity)
 620 {
 621         _osd_req_encode_common(or, OSD_ACT_FORMAT_OSD, &osd_root_object, 0,
 622                                 tot_capacity);
 623 }
 624 EXPORT_SYMBOL(osd_req_format);
 625
 626 int osd_req_list_dev_partitions(struct osd_request *or,
 627         osd_id initial_id, struct osd_obj_id_list *list, unsigned nelem)
 628 {
 629         return osd_req_list_partition_objects(or, 0, initial_id, list, nelem);
 630 }
 631 EXPORT_SYMBOL(osd_req_list_dev_partitions);
 632
 633 static void _osd_req_encode_flush(struct osd_request *or,
 634         enum osd_options_flush_scope_values op)
 635 {
 636         struct osd_cdb_head *ocdb = osd_cdb_head(&or->cdb);
 637
 638         ocdb->command_specific_options = op;
 639 }
 640
 641 void osd_req_flush_obsd(struct osd_request *or,
 642         enum osd_options_flush_scope_values op)
 643 {
 644         _osd_req_encode_common(or, OSD_ACT_FLUSH_OSD, &osd_root_object, 0, 0);
 645         _osd_req_encode_flush(or, op);
 646 }
 647 EXPORT_SYMBOL(osd_req_flush_obsd);
 648
 649 /*TODO: void osd_req_perform_scsi_command(struct osd_request *,
 650         const u8 *cdb, ...); */
 651 /*TODO: void osd_req_task_management(struct osd_request *, ...); */
 652
 653 /*
 654  * Partition commands
 655  */
 656 static void _osd_req_encode_partition(struct osd_request *or,
 657         __be16 act, osd_id partition)
 658 {
 659         struct osd_obj_id par = {
 660                 .partition = partition,
 661                 .id = 0,
 662         };
 663
 664         _osd_req_encode_common(or, act, &par, 0, 0);
 665 }
 666
 667 void osd_req_create_partition(struct osd_request *or, osd_id partition)
 668 {
 669         _osd_req_encode_partition(or, OSD_ACT_CREATE_PARTITION, partition);
 670 }
 671 EXPORT_SYMBOL(osd_req_create_partition);
 672
 673 void osd_req_remove_partition(struct osd_request *or, osd_id partition)
 674 {
 675         _osd_req_encode_partition(or, OSD_ACT_REMOVE_PARTITION, partition);
 676 }
 677 EXPORT_SYMBOL(osd_req_remove_partition);
 678
 679 /*TODO: void osd_req_set_partition_key(struct osd_request *,
 680         osd_id partition, u8 new_key_id[OSD_CRYPTO_KEYID_SIZE],
 681         u8 seed[OSD_CRYPTO_SEED_SIZE]); */
 682
 683 static int _osd_req_list_objects(struct osd_request *or,
 684         __be16 action, const struct osd_obj_id *obj, osd_id initial_id,
 685         struct osd_obj_id_list *list, unsigned nelem)
 686 {
 687         struct request_queue *q = osd_request_queue(or->osd_dev);
 688         u64 len = nelem * sizeof(osd_id) + sizeof(*list);
 689         struct bio *bio;
 690
 691         _osd_req_encode_common(or, action, obj, (u64)initial_id, len);
 692
 693         if (list->list_identifier)
 694                 _osd_req_encode_olist(or, list);
 695
 696         WARN_ON(or->in.bio);
 697         bio = bio_map_kern(q, list, len, or->alloc_flags);
 698         if (IS_ERR(bio)) {
 699                 OSD_ERR("!!! Failed to allocate list_objects BIO\n");
 700                 return PTR_ERR(bio);
 701         }
 702
 703         bio->bi_rw &= ~(1 << BIO_RW);
 704         or->in.bio = bio;
 705         or->in.total_bytes = bio->bi_size;
 706         return 0;
 707 }
 708
 709 int osd_req_list_partition_collections(struct osd_request *or,
 710         osd_id partition, osd_id initial_id, struct osd_obj_id_list *list,
 711         unsigned nelem)
 712 {
 713         struct osd_obj_id par = {
 714                 .partition = partition,
 715                 .id = 0,
 716         };
 717
 718         return osd_req_list_collection_objects(or, &par, initial_id, list,
 719                                                nelem);
 720 }
 721 EXPORT_SYMBOL(osd_req_list_partition_collections);
 722
 723 int osd_req_list_partition_objects(struct osd_request *or,
 724         osd_id partition, osd_id initial_id, struct osd_obj_id_list *list,
 725         unsigned nelem)
 726 {
 727         struct osd_obj_id par = {
 728                 .partition = partition,
 729                 .id = 0,
 730         };
 731
 732         return _osd_req_list_objects(or, OSD_ACT_LIST, &par, initial_id, list,
 733                                      nelem);
 734 }
 735 EXPORT_SYMBOL(osd_req_list_partition_objects);
 736
 737 void osd_req_flush_partition(struct osd_request *or,
 738         osd_id partition, enum osd_options_flush_scope_values op)
 739 {
 740         _osd_req_encode_partition(or, OSD_ACT_FLUSH_PARTITION, partition);
 741         _osd_req_encode_flush(or, op);
 742 }
 743 EXPORT_SYMBOL(osd_req_flush_partition);
 744
 745 /*
 746  * Collection commands
 747  */
 748 /*TODO: void osd_req_create_collection(struct osd_request *,
 749         const struct osd_obj_id *); */
 750 /*TODO: void osd_req_remove_collection(struct osd_request *,
 751         const struct osd_obj_id *); */
 752
 753 int osd_req_list_collection_objects(struct osd_request *or,
 754         const struct osd_obj_id *obj, osd_id initial_id,
 755         struct osd_obj_id_list *list, unsigned nelem)
 756 {
 757         return _osd_req_list_objects(or, OSD_ACT_LIST_COLLECTION, obj,
 758                                      initial_id, list, nelem);
 759 }
 760 EXPORT_SYMBOL(osd_req_list_collection_objects);
 761
 762 /*TODO: void query(struct osd_request *, ...); V2 */
 763
 764 void osd_req_flush_collection(struct osd_request *or,
 765         const struct osd_obj_id *obj, enum osd_options_flush_scope_values op)
 766 {
 767         _osd_req_encode_common(or, OSD_ACT_FLUSH_PARTITION, obj, 0, 0);
 768         _osd_req_encode_flush(or, op);
 769 }
 770 EXPORT_SYMBOL(osd_req_flush_collection);
 771
 772 /*TODO: void get_member_attrs(struct osd_request *, ...); V2 */
 773 /*TODO: void set_member_attrs(struct osd_request *, ...); V2 */
 774
 775 /*
 776  * Object commands
 777  */
 778 void osd_req_create_object(struct osd_request *or, struct osd_obj_id *obj)
 779 {
 780         _osd_req_encode_common(or, OSD_ACT_CREATE, obj, 0, 0);
 781 }
 782 EXPORT_SYMBOL(osd_req_create_object);
 783
 784 void osd_req_remove_object(struct osd_request *or, struct osd_obj_id *obj)
 785 {
 786         _osd_req_encode_common(or, OSD_ACT_REMOVE, obj, 0, 0);
 787 }
 788 EXPORT_SYMBOL(osd_req_remove_object);
 789
 790
 791 /*TODO: void osd_req_create_multi(struct osd_request *or,
 792         struct osd_obj_id *first, struct osd_obj_id_list *list, unsigned nelem);
 793 */
 794
 795 void osd_req_write(struct osd_request *or,
 796         const struct osd_obj_id *obj, u64 offset,
 797         struct bio *bio, u64 len)
 798 {
 799         _osd_req_encode_common(or, OSD_ACT_WRITE, obj, offset, len);
 800         WARN_ON(or->out.bio || or->out.total_bytes);
 801         WARN_ON(0 ==  bio_rw_flagged(bio, BIO_RW));
 802         or->out.bio = bio;
 803         or->out.total_bytes = len;
 804 }
 805 EXPORT_SYMBOL(osd_req_write);
 806
 807 int osd_req_write_kern(struct osd_request *or,
 808         const struct osd_obj_id *obj, u64 offset, void* buff, u64 len)
 809 {
 810         struct request_queue *req_q = osd_request_queue(or->osd_dev);
 811         struct bio *bio = bio_map_kern(req_q, buff, len, GFP_KERNEL);
 812
 813         if (IS_ERR(bio))
 814                 return PTR_ERR(bio);
 815
 816         bio->bi_rw |= (1 << BIO_RW); /* FIXME: bio_set_dir() */
 817         osd_req_write(or, obj, offset, bio, len);
 818         return 0;
 819 }
 820 EXPORT_SYMBOL(osd_req_write_kern);
 821
 822 /*TODO: void osd_req_append(struct osd_request *,
 823         const struct osd_obj_id *, struct bio *data_out); */
 824 /*TODO: void osd_req_create_write(struct osd_request *,
 825         const struct osd_obj_id *, struct bio *data_out, u64 offset); */
 826 /*TODO: void osd_req_clear(struct osd_request *,
 827         const struct osd_obj_id *, u64 offset, u64 len); */
 828 /*TODO: void osd_req_punch(struct osd_request *,
 829         const struct osd_obj_id *, u64 offset, u64 len); V2 */
 830
 831 void osd_req_flush_object(struct osd_request *or,
 832         const struct osd_obj_id *obj, enum osd_options_flush_scope_values op,
 833         /*V2*/ u64 offset, /*V2*/ u64 len)
 834 {
 835         if (unlikely(osd_req_is_ver1(or) && (offset || len))) {
 836                 OSD_DEBUG("OSD Ver1 flush on specific range ignored\n");
 837                 offset = 0;
 838                 len = 0;
 839         }
 840
 841         _osd_req_encode_common(or, OSD_ACT_FLUSH, obj, offset, len);
 842         _osd_req_encode_flush(or, op);
 843 }
 844 EXPORT_SYMBOL(osd_req_flush_object);
 845
 846 void osd_req_read(struct osd_request *or,
 847         const struct osd_obj_id *obj, u64 offset,
 848         struct bio *bio, u64 len)
 849 {
 850         _osd_req_encode_common(or, OSD_ACT_READ, obj, offset, len);
 851         WARN_ON(or->in.bio || or->in.total_bytes);
 852         WARN_ON(1 == bio_rw_flagged(bio, BIO_RW));
 853         or->in.bio = bio;
 854         or->in.total_bytes = len;
 855 }
 856 EXPORT_SYMBOL(osd_req_read);
 857
 858 int osd_req_read_kern(struct osd_request *or,
 859         const struct osd_obj_id *obj, u64 offset, void* buff, u64 len)
 860 {
 861         struct request_queue *req_q = osd_request_queue(or->osd_dev);
 862         struct bio *bio = bio_map_kern(req_q, buff, len, GFP_KERNEL);
 863
 864         if (IS_ERR(bio))
 865                 return PTR_ERR(bio);
 866
 867         osd_req_read(or, obj, offset, bio, len);
 868         return 0;
 869 }
 870 EXPORT_SYMBOL(osd_req_read_kern);
 871
 872 void osd_req_get_attributes(struct osd_request *or,
 873         const struct osd_obj_id *obj)
 874 {
 875         _osd_req_encode_common(or, OSD_ACT_GET_ATTRIBUTES, obj, 0, 0);
 876 }
 877 EXPORT_SYMBOL(osd_req_get_attributes);
 878
 879 void osd_req_set_attributes(struct osd_request *or,
 880         const struct osd_obj_id *obj)
 881 {
 882         _osd_req_encode_common(or, OSD_ACT_SET_ATTRIBUTES, obj, 0, 0);
 883 }
 884 EXPORT_SYMBOL(osd_req_set_attributes);
 885
 886 /*
 887  * Attributes List-mode
 888  */
 889
 890 int osd_req_add_set_attr_list(struct osd_request *or,
 891         const struct osd_attr *oa, unsigned nelem)
 892 {
 893         unsigned total_bytes = or->set_attr.total_bytes;
 894         void *attr_last;
 895         int ret;
 896
 897         if (or->attributes_mode &&
 898             or->attributes_mode != OSD_CDB_GET_SET_ATTR_LISTS) {
 899                 WARN_ON(1);
 900                 return -EINVAL;
 901         }
 902         or->attributes_mode = OSD_CDB_GET_SET_ATTR_LISTS;
 903
 904         if (!total_bytes) { /* first-time: allocate and put list header */
 905                 total_bytes = _osd_req_sizeof_alist_header(or);
 906                 ret = _alloc_set_attr_list(or, oa, nelem, total_bytes);
 907                 if (ret)
 908                         return ret;
 909                 _osd_req_set_alist_type(or, or->set_attr.buff,
 910                                         OSD_ATTR_LIST_SET_RETRIEVE);
 911         }
 912         attr_last = or->set_attr.buff + total_bytes;
 913
 914         for (; nelem; --nelem) {
 915                 unsigned elem_size = _osd_req_alist_elem_size(or, oa->len);
 916
 917                 total_bytes += elem_size;
 918                 if (unlikely(or->set_attr.alloc_size < total_bytes)) {
 919                         or->set_attr.total_bytes = total_bytes - elem_size;
 920                         ret = _alloc_set_attr_list(or, oa, nelem, total_bytes);
 921                         if (ret)
 922                                 return ret;
 923                         attr_last =
 924                                 or->set_attr.buff + or->set_attr.total_bytes;
 925                 }
 926
 927                 _osd_req_alist_elem_encode(or, attr_last, oa);
 928
 929                 attr_last += elem_size;
 930                 ++oa;
 931         }
 932
 933         or->set_attr.total_bytes = total_bytes;
 934         return 0;
 935 }
 936 EXPORT_SYMBOL(osd_req_add_set_attr_list);
 937
 938 static int _req_append_segment(struct osd_request *or,
 939         unsigned padding, struct _osd_req_data_segment *seg,
 940         struct _osd_req_data_segment *last_seg, struct _osd_io_info *io)
 941 {
 942         void *pad_buff;
 943         int ret;
 944
 945         if (padding) {
 946                 /* check if we can just add it to last buffer */
 947                 if (last_seg &&
 948                     (padding <= last_seg->alloc_size - last_seg->total_bytes))
 949                         pad_buff = last_seg->buff + last_seg->total_bytes;
 950                 else
 951                         pad_buff = io->pad_buff;
 952
 953                 ret = blk_rq_map_kern(io->req->q, io->req, pad_buff, padding,
 954                                        or->alloc_flags);
 955                 if (ret)
 956                         return ret;
 957                 io->total_bytes += padding;
 958         }
 959
 960         ret = blk_rq_map_kern(io->req->q, io->req, seg->buff, seg->total_bytes,
 961                                or->alloc_flags);
 962         if (ret)
 963                 return ret;
 964
 965         io->total_bytes += seg->total_bytes;
 966         OSD_DEBUG("padding=%d buff=%p total_bytes=%d\n", padding, seg->buff,
 967                   seg->total_bytes);
 968         return 0;
 969 }
 970
 971 static int _osd_req_finalize_set_attr_list(struct osd_request *or)
 972 {
 973         struct osd_cdb_head *cdbh = osd_cdb_head(&or->cdb);
 974         unsigned padding;
 975         int ret;
 976
 977         if (!or->set_attr.total_bytes) {
 978                 cdbh->attrs_list.set_attr_offset = OSD_OFFSET_UNUSED;
 979                 return 0;
 980         }
 981
 982         cdbh->attrs_list.set_attr_bytes = cpu_to_be32(or->set_attr.total_bytes);
 983         cdbh->attrs_list.set_attr_offset =
 984                 osd_req_encode_offset(or, or->out.total_bytes, &padding);
 985
 986         ret = _req_append_segment(or, padding, &or->set_attr,
 987                                   or->out.last_seg, &or->out);
 988         if (ret)
 989                 return ret;
 990
 991         or->out.last_seg = &or->set_attr;
 992         return 0;
 993 }
 994
 995 int osd_req_add_get_attr_list(struct osd_request *or,
 996         const struct osd_attr *oa, unsigned nelem)
 997 {
 998         unsigned total_bytes = or->enc_get_attr.total_bytes;
 999         void *attr_last;
1000         int ret;
1001
1002         if (or->attributes_mode &&
1003             or->attributes_mode != OSD_CDB_GET_SET_ATTR_LISTS) {
1004                 WARN_ON(1);
1005                 return -EINVAL;
1006         }
1007         or->attributes_mode = OSD_CDB_GET_SET_ATTR_LISTS;
1008
1009         /* first time calc data-in list header size */
1010         if (!or->get_attr.total_bytes)
1011                 or->get_attr.total_bytes = _osd_req_sizeof_alist_header(or);
1012
1013         /* calc data-out info */
1014         if (!total_bytes) { /* first-time: allocate and put list header */
1015                 unsigned max_bytes;
1016
1017                 total_bytes = _osd_req_sizeof_alist_header(or);
1018                 max_bytes = total_bytes +
1019                         nelem * sizeof(struct osd_attributes_list_attrid);
1020                 ret = _alloc_get_attr_desc(or, max_bytes);
1021                 if (ret)
1022                         return ret;
1023
1024                 _osd_req_set_alist_type(or, or->enc_get_attr.buff,
1025                                         OSD_ATTR_LIST_GET);
1026         }
1027         attr_last = or->enc_get_attr.buff + total_bytes;
1028
1029         for (; nelem; --nelem) {
1030                 struct osd_attributes_list_attrid *attrid;
1031                 const unsigned cur_size = sizeof(*attrid);
1032
1033                 total_bytes += cur_size;
1034                 if (unlikely(or->enc_get_attr.alloc_size < total_bytes)) {
1035                         or->enc_get_attr.total_bytes = total_bytes - cur_size;
1036                         ret = _alloc_get_attr_desc(or,
1037                                         total_bytes + nelem * sizeof(*attrid));
1038                         if (ret)
1039                                 return ret;
1040                         attr_last = or->enc_get_attr.buff +
1041                                 or->enc_get_attr.total_bytes;
1042                 }
1043
1044                 attrid = attr_last;
1045                 attrid->attr_page = cpu_to_be32(oa->attr_page);
1046                 attrid->attr_id = cpu_to_be32(oa->attr_id);
1047
1048                 attr_last += cur_size;
1049
1050                 /* calc data-in size */
1051                 or->get_attr.total_bytes +=
1052                         _osd_req_alist_elem_size(or, oa->len);
1053                 ++oa;
1054         }
1055
1056         or->enc_get_attr.total_bytes = total_bytes;
1057
1058         OSD_DEBUG(
1059                "get_attr.total_bytes=%u(%u) enc_get_attr.total_bytes=%u(%Zu)\n",
1060                or->get_attr.total_bytes,
1061                or->get_attr.total_bytes - _osd_req_sizeof_alist_header(or),
1062                or->enc_get_attr.total_bytes,
1063                (or->enc_get_attr.total_bytes - _osd_req_sizeof_alist_header(or))
1064                         / sizeof(struct osd_attributes_list_attrid));
1065
1066         return 0;
1067 }
1068 EXPORT_SYMBOL(osd_req_add_get_attr_list);
1069
1070 static int _osd_req_finalize_get_attr_list(struct osd_request *or)
1071 {
1072         struct osd_cdb_head *cdbh = osd_cdb_head(&or->cdb);
1073         unsigned out_padding;
1074         unsigned in_padding;
1075         int ret;
1076
1077         if (!or->enc_get_attr.total_bytes) {
1078                 cdbh->attrs_list.get_attr_desc_offset = OSD_OFFSET_UNUSED;
1079                 cdbh->attrs_list.get_attr_offset = OSD_OFFSET_UNUSED;
1080                 return 0;
1081         }
1082
1083         ret = _alloc_get_attr_list(or);
1084         if (ret)
1085                 return ret;
1086
1087         /* The out-going buffer info update */
1088         OSD_DEBUG("out-going\n");
1089         cdbh->attrs_list.get_attr_desc_bytes =
1090                 cpu_to_be32(or->enc_get_attr.total_bytes);
1091
1092         cdbh->attrs_list.get_attr_desc_offset =
1093                 osd_req_encode_offset(or, or->out.total_bytes, &out_padding);
1094
1095         ret = _req_append_segment(or, out_padding, &or->enc_get_attr,
1096                                   or->out.last_seg, &or->out);
1097         if (ret)
1098                 return ret;
1099         or->out.last_seg = &or->enc_get_attr;
1100
1101         /* The incoming buffer info update */
1102         OSD_DEBUG("in-coming\n");
1103         cdbh->attrs_list.get_attr_alloc_length =
1104                 cpu_to_be32(or->get_attr.total_bytes);
1105
1106         cdbh->attrs_list.get_attr_offset =
1107                 osd_req_encode_offset(or, or->in.total_bytes, &in_padding);
1108
1109         ret = _req_append_segment(or, in_padding, &or->get_attr, NULL,
1110                                   &or->in);
1111         if (ret)
1112                 return ret;
1113         or->in.last_seg = &or->get_attr;
1114
1115         return 0;
1116 }
1117
1118 int osd_req_decode_get_attr_list(struct osd_request *or,
1119         struct osd_attr *oa, int *nelem, void **iterator)
1120 {
1121         unsigned cur_bytes, returned_bytes;
1122         int n;
1123         const unsigned sizeof_attr_list = _osd_req_sizeof_alist_header(or);
1124         void *cur_p;
1125
1126         if (!_osd_req_is_alist_type(or, or->get_attr.buff,
1127                                     OSD_ATTR_LIST_SET_RETRIEVE)) {
1128                 oa->attr_page = 0;
1129                 oa->attr_id = 0;
1130                 oa->val_ptr = NULL;
1131                 oa->len = 0;
1132                 *iterator = NULL;
1133                 return 0;
1134         }
1135
1136         if (*iterator) {
1137                 BUG_ON((*iterator < or->get_attr.buff) ||
1138                      (or->get_attr.buff + or->get_attr.alloc_size < *iterator));
1139                 cur_p = *iterator;
1140                 cur_bytes = (*iterator - or->get_attr.buff) - sizeof_attr_list;
1141                 returned_bytes = or->get_attr.total_bytes;
1142         } else { /* first time decode the list header */
1143                 cur_bytes = sizeof_attr_list;
1144                 returned_bytes = _osd_req_alist_size(or, or->get_attr.buff) +
1145                                         sizeof_attr_list;
1146
1147                 cur_p = or->get_attr.buff + sizeof_attr_list;
1148
1149                 if (returned_bytes > or->get_attr.alloc_size) {
1150                         OSD_DEBUG("target report: space was not big enough! "
1151                                   "Allocate=%u Needed=%u\n",
1152                                   or->get_attr.alloc_size,
1153                                   returned_bytes + sizeof_attr_list);
1154
1155                         returned_bytes =
1156                                 or->get_attr.alloc_size - sizeof_attr_list;
1157                 }
1158                 or->get_attr.total_bytes = returned_bytes;
1159         }
1160
1161         for (n = 0; (n < *nelem) && (cur_bytes < returned_bytes); ++n) {
1162                 int inc = _osd_req_alist_elem_decode(or, cur_p, oa,
1163                                                  returned_bytes - cur_bytes);
1164
1165                 if (inc < 0) {
1166                         OSD_ERR("BAD FOOD from target. list not valid!"
1167                                 "c=%d r=%d n=%d\n",
1168                                 cur_bytes, returned_bytes, n);
1169                         oa->val_ptr = NULL;
1170                         break;
1171                 }
1172
1173                 cur_bytes += inc;
1174                 cur_p += inc;
1175                 ++oa;
1176         }
1177
1178         *iterator = (returned_bytes - cur_bytes) ? cur_p : NULL;
1179         *nelem = n;
1180         return returned_bytes - cur_bytes;
1181 }
1182 EXPORT_SYMBOL(osd_req_decode_get_attr_list);
1183
1184 /*
1185  * Attributes Page-mode
1186  */
1187
1188 int osd_req_add_get_attr_page(struct osd_request *or,
1189         u32 page_id, void *attar_page, unsigned max_page_len,
1190         const struct osd_attr *set_one_attr)
1191 {
1192         struct osd_cdb_head *cdbh = osd_cdb_head(&or->cdb);
1193
1194         if (or->attributes_mode &&
1195             or->attributes_mode != OSD_CDB_GET_ATTR_PAGE_SET_ONE) {
1196                 WARN_ON(1);
1197                 return -EINVAL;
1198         }
1199         or->attributes_mode = OSD_CDB_GET_ATTR_PAGE_SET_ONE;
1200
1201         or->get_attr.buff = attar_page;
1202         or->get_attr.total_bytes = max_page_len;
1203
1204         or->set_attr.buff = set_one_attr->val_ptr;
1205         or->set_attr.total_bytes = set_one_attr->len;
1206
1207         cdbh->attrs_page.get_attr_page = cpu_to_be32(page_id);
1208         cdbh->attrs_page.get_attr_alloc_length = cpu_to_be32(max_page_len);
1209         /* ocdb->attrs_page.get_attr_offset; */
1210
1211         cdbh->attrs_page.set_attr_page = cpu_to_be32(set_one_attr->attr_page);
1212         cdbh->attrs_page.set_attr_id = cpu_to_be32(set_one_attr->attr_id);
1213         cdbh->attrs_page.set_attr_length = cpu_to_be32(set_one_attr->len);
1214         /* ocdb->attrs_page.set_attr_offset; */
1215         return 0;
1216 }
1217 EXPORT_SYMBOL(osd_req_add_get_attr_page);
1218
1219 static int _osd_req_finalize_attr_page(struct osd_request *or)
1220 {
1221         struct osd_cdb_head *cdbh = osd_cdb_head(&or->cdb);
1222         unsigned in_padding, out_padding;
1223         int ret;
1224
1225         /* returned page */
1226         cdbh->attrs_page.get_attr_offset =
1227                 osd_req_encode_offset(or, or->in.total_bytes, &in_padding);
1228
1229         ret = _req_append_segment(or, in_padding, &or->get_attr, NULL,
1230                                   &or->in);
1231         if (ret)
1232                 return ret;
1233
1234         /* set one value */
1235         cdbh->attrs_page.set_attr_offset =
1236                 osd_req_encode_offset(or, or->out.total_bytes, &out_padding);
1237
1238         ret = _req_append_segment(or, out_padding, &or->enc_get_attr, NULL,
1239                                   &or->out);
1240         return ret;
1241 }
1242
1243 static inline void osd_sec_parms_set_out_offset(bool is_v1,
1244         struct osd_security_parameters *sec_parms, osd_cdb_offset offset)
1245 {
1246         if (is_v1)
1247                 sec_parms->v1.data_out_integrity_check_offset = offset;
1248         else
1249                 sec_parms->v2.data_out_integrity_check_offset = offset;
1250 }
1251
1252 static inline void osd_sec_parms_set_in_offset(bool is_v1,
1253         struct osd_security_parameters *sec_parms, osd_cdb_offset offset)
1254 {
1255         if (is_v1)
1256                 sec_parms->v1.data_in_integrity_check_offset = offset;
1257         else
1258                 sec_parms->v2.data_in_integrity_check_offset = offset;
1259 }
1260
1261 static int _osd_req_finalize_data_integrity(struct osd_request *or,
1262         bool has_in, bool has_out, u64 out_data_bytes, const u8 *cap_key)
1263 {
1264         struct osd_security_parameters *sec_parms = _osd_req_sec_params(or);
1265         int ret;
1266
1267         if (!osd_is_sec_alldata(sec_parms))
1268                 return 0;
1269
1270         if (has_out) {
1271                 struct _osd_req_data_segment seg = {
1272                         .buff = &or->out_data_integ,
1273                         .total_bytes = sizeof(or->out_data_integ),
1274                 };
1275                 unsigned pad;
1276
1277                 or->out_data_integ.data_bytes = cpu_to_be64(out_data_bytes);
1278                 or->out_data_integ.set_attributes_bytes = cpu_to_be64(
1279                         or->set_attr.total_bytes);
1280                 or->out_data_integ.get_attributes_bytes = cpu_to_be64(
1281                         or->enc_get_attr.total_bytes);
1282
1283                 osd_sec_parms_set_out_offset(osd_req_is_ver1(or), sec_parms,
1284                         osd_req_encode_offset(or, or->out.total_bytes, &pad));
1285
1286                 ret = _req_append_segment(or, pad, &seg, or->out.last_seg,
1287                                           &or->out);
1288                 if (ret)
1289                         return ret;
1290                 or->out.last_seg = NULL;
1291
1292                 /* they are now all chained to request sign them all together */
1293                 osd_sec_sign_data(&or->out_data_integ, or->out.req->bio,
1294                                   cap_key);
1295         }
1296
1297         if (has_in) {
1298                 struct _osd_req_data_segment seg = {
1299                         .buff = &or->in_data_integ,
1300                         .total_bytes = sizeof(or->in_data_integ),
1301                 };
1302                 unsigned pad;
1303
1304                 osd_sec_parms_set_in_offset(osd_req_is_ver1(or), sec_parms,
1305                         osd_req_encode_offset(or, or->in.total_bytes, &pad));
1306
1307                 ret = _req_append_segment(or, pad, &seg, or->in.last_seg,
1308                                           &or->in);
1309                 if (ret)
1310                         return ret;
1311
1312                 or->in.last_seg = NULL;
1313         }
1314
1315         return 0;
1316 }
1317
1318 /*
1319  * osd_finalize_request and helpers
1320  */
1321 static struct request *_make_request(struct request_queue *q, bool has_write,
1322                               struct _osd_io_info *oii, gfp_t flags)
1323 {
1324         if (oii->bio)
1325                 return blk_make_request(q, oii->bio, flags);
1326         else {
1327                 struct request *req;
1328
1329                 req = blk_get_request(q, has_write ? WRITE : READ, flags);
1330                 if (unlikely(!req))
1331                         return ERR_PTR(-ENOMEM);
1332
1333                 return req;
1334         }
1335 }
1336
1337 static int _init_blk_request(struct osd_request *or,
1338         bool has_in, bool has_out)
1339 {
1340         gfp_t flags = or->alloc_flags;
1341         struct scsi_device *scsi_device = or->osd_dev->scsi_device;
1342         struct request_queue *q = scsi_device->request_queue;
1343         struct request *req;
1344         int ret;
1345
1346         req = _make_request(q, has_out, has_out ? &or->out : &or->in, flags);
1347         if (IS_ERR(req)) {
1348                 ret = PTR_ERR(req);
1349                 goto out;
1350         }
1351
1352         or->request = req;
1353         req->cmd_type = REQ_TYPE_BLOCK_PC;
1354         req->cmd_flags |= REQ_QUIET;
1355
1356         req->timeout = or->timeout;
1357         req->retries = or->retries;
1358         req->sense = or->sense;
1359         req->sense_len = 0;
1360
1361         if (has_out) {
1362                 or->out.req = req;
1363                 if (has_in) {
1364                         /* allocate bidi request */
1365                         req = _make_request(q, false, &or->in, flags);
1366                         if (IS_ERR(req)) {
1367                                 OSD_DEBUG("blk_get_request for bidi failed\n");
1368                                 ret = PTR_ERR(req);
1369                                 goto out;
1370                         }
1371                         req->cmd_type = REQ_TYPE_BLOCK_PC;
1372                         or->in.req = or->request->next_rq = req;
1373                 }
1374         } else if (has_in)
1375                 or->in.req = req;
1376
1377         ret = 0;
1378 out:
1379         OSD_DEBUG("or=%p has_in=%d has_out=%d => %d, %p\n",
1380                         or, has_in, has_out, ret, or->request);
1381         return ret;
1382 }
1383
1384 int osd_finalize_request(struct osd_request *or,
1385         u8 options, const void *cap, const u8 *cap_key)
1386 {
1387         struct osd_cdb_head *cdbh = osd_cdb_head(&or->cdb);
1388         bool has_in, has_out;
1389         u64 out_data_bytes = or->out.total_bytes;
1390         int ret;
1391
1392         if (options & OSD_REQ_FUA)
1393                 cdbh->options |= OSD_CDB_FUA;
1394
1395         if (options & OSD_REQ_DPO)
1396                 cdbh->options |= OSD_CDB_DPO;
1397
1398         if (options & OSD_REQ_BYPASS_TIMESTAMPS)
1399                 cdbh->timestamp_control = OSD_CDB_BYPASS_TIMESTAMPS;
1400
1401         osd_set_caps(&or->cdb, cap);
1402
1403         has_in = or->in.bio || or->get_attr.total_bytes;
1404         has_out = or->out.bio || or->set_attr.total_bytes ||
1405                 or->enc_get_attr.total_bytes;
1406
1407         ret = _init_blk_request(or, has_in, has_out);
1408         if (ret) {
1409                 OSD_DEBUG("_init_blk_request failed\n");
1410                 return ret;
1411         }
1412
1413         or->out.pad_buff = sg_out_pad_buffer;
1414         or->in.pad_buff = sg_in_pad_buffer;
1415
1416         if (!or->attributes_mode)
1417                 or->attributes_mode = OSD_CDB_GET_SET_ATTR_LISTS;
1418         cdbh->command_specific_options |= or->attributes_mode;
1419         if (or->attributes_mode == OSD_CDB_GET_ATTR_PAGE_SET_ONE) {
1420                 ret = _osd_req_finalize_attr_page(or);
1421         } else {
1422                 /* TODO: I think that for the GET_ATTR command these 2 should
1423                  * be reversed to keep them in execution order (for embeded
1424                  * targets with low memory footprint)
1425                  */
1426                 ret = _osd_req_finalize_set_attr_list(or);
1427                 if (ret) {
1428                         OSD_DEBUG("_osd_req_finalize_set_attr_list failed\n");
1429                         return ret;
1430                 }
1431
1432                 ret = _osd_req_finalize_get_attr_list(or);
1433                 if (ret) {
1434                         OSD_DEBUG("_osd_req_finalize_get_attr_list failed\n");
1435                         return ret;
1436                 }
1437         }
1438
1439         ret = _osd_req_finalize_data_integrity(or, has_in, has_out,
1440                                                out_data_bytes, cap_key);
1441         if (ret)
1442                 return ret;
1443
1444         osd_sec_sign_cdb(&or->cdb, cap_key);
1445
1446         or->request->cmd = or->cdb.buff;
1447         or->request->cmd_len = _osd_req_cdb_len(or);
1448
1449         return 0;
1450 }
1451 EXPORT_SYMBOL(osd_finalize_request);
1452
1453 #define OSD_SENSE_PRINT1(fmt, a...) \
1454         do { \
1455                 if (__cur_sense_need_output) \
1456                         OSD_ERR(fmt, ##a); \
1457         } while (0)
1458
1459 #define OSD_SENSE_PRINT2(fmt, a...) OSD_SENSE_PRINT1("    " fmt, ##a)
1460
1461 int osd_req_decode_sense_full(struct osd_request *or,
1462         struct osd_sense_info *osi, bool silent,
1463         struct osd_obj_id *bad_obj_list __unused, int max_obj __unused,
1464         struct osd_attr *bad_attr_list, int max_attr)
1465 {
1466         int sense_len, original_sense_len;
1467         struct osd_sense_info local_osi;
1468         struct scsi_sense_descriptor_based *ssdb;
1469         void *cur_descriptor;
1470 #if (CONFIG_SCSI_OSD_DPRINT_SENSE == 0)
1471         const bool __cur_sense_need_output = false;
1472 #else
1473         bool __cur_sense_need_output = !silent;
1474 #endif
1475
1476         if (!or->request->errors)
1477                 return 0;
1478
1479         ssdb = or->request->sense;
1480         sense_len = or->request->sense_len;
1481         if ((sense_len < (int)sizeof(*ssdb) || !ssdb->sense_key)) {
1482                 OSD_ERR("Block-layer returned error(0x%x) but "
1483                         "sense_len(%u) || key(%d) is empty\n",
1484                         or->request->errors, sense_len, ssdb->sense_key);
1485                 return -EIO;
1486         }
1487
1488         if ((ssdb->response_code != 0x72) && (ssdb->response_code != 0x73)) {
1489                 OSD_ERR("Unrecognized scsi sense: rcode=%x length=%d\n",
1490                         ssdb->response_code, sense_len);
1491                 return -EIO;
1492         }
1493
1494         osi = osi ? : &local_osi;
1495         memset(osi, 0, sizeof(*osi));
1496         osi->key = ssdb->sense_key;
1497         osi->additional_code = be16_to_cpu(ssdb->additional_sense_code);
1498         original_sense_len = ssdb->additional_sense_length + 8;
1499
1500 #if (CONFIG_SCSI_OSD_DPRINT_SENSE == 1)
1501         if (__cur_sense_need_output)
1502                 __cur_sense_need_output = (osi->key > scsi_sk_recovered_error);
1503 #endif
1504         OSD_SENSE_PRINT1("Main Sense information key=0x%x length(%d, %d) "
1505                         "additional_code=0x%x\n",
1506                         osi->key, original_sense_len, sense_len,
1507                         osi->additional_code);
1508
1509         if (original_sense_len < sense_len)
1510                 sense_len = original_sense_len;
1511
1512         cur_descriptor = ssdb->ssd;
1513         sense_len -= sizeof(*ssdb);
1514         while (sense_len > 0) {
1515                 struct scsi_sense_descriptor *ssd = cur_descriptor;
1516                 int cur_len = ssd->additional_length + 2;
1517
1518                 sense_len -= cur_len;
1519
1520                 if (sense_len < 0)
1521                         break; /* sense was truncated */
1522
1523                 switch (ssd->descriptor_type) {
1524                 case scsi_sense_information:
1525                 case scsi_sense_command_specific_information:
1526                 {
1527                         struct scsi_sense_command_specific_data_descriptor
1528                                 *sscd = cur_descriptor;
1529
1530                         osi->command_info =
1531                                 get_unaligned_be64(&sscd->information) ;
1532                         OSD_SENSE_PRINT2(
1533                                 "command_specific_information 0x%llx \n",
1534                                 _LLU(osi->command_info));
1535                         break;
1536                 }
1537                 case scsi_sense_key_specific:
1538                 {
1539                         struct scsi_sense_key_specific_data_descriptor
1540                                 *ssks = cur_descriptor;
1541
1542                         osi->sense_info = get_unaligned_be16(&ssks->value);
1543                         OSD_SENSE_PRINT2(
1544                                 "sense_key_specific_information %u"
1545                                 "sksv_cd_bpv_bp (0x%x)\n",
1546                                 osi->sense_info, ssks->sksv_cd_bpv_bp);
1547                         break;
1548                 }
1549                 case osd_sense_object_identification:
1550                 { /*FIXME: Keep first not last, Store in array*/
1551                         struct osd_sense_identification_data_descriptor
1552                                 *osidd = cur_descriptor;
1553
1554                         osi->not_initiated_command_functions =
1555                                 le32_to_cpu(osidd->not_initiated_functions);
1556                         osi->completed_command_functions =
1557                                 le32_to_cpu(osidd->completed_functions);
1558                         osi->obj.partition = be64_to_cpu(osidd->partition_id);
1559                         osi->obj.id = be64_to_cpu(osidd->object_id);
1560                         OSD_SENSE_PRINT2(
1561                                 "object_identification pid=0x%llx oid=0x%llx\n",
1562                                 _LLU(osi->obj.partition), _LLU(osi->obj.id));
1563                         OSD_SENSE_PRINT2(
1564                                 "not_initiated_bits(%x) "
1565                                 "completed_command_bits(%x)\n",
1566                                 osi->not_initiated_command_functions,
1567                                 osi->completed_command_functions);
1568                         break;
1569                 }
1570                 case osd_sense_response_integrity_check:
1571                 {
1572                         struct osd_sense_response_integrity_check_descriptor
1573                                 *osricd = cur_descriptor;
1574                         const unsigned len =
1575                                           sizeof(osricd->integrity_check_value);
1576                         char key_dump[len*4 + 2]; /* 2nibbles+space+ASCII */
1577
1578                         hex_dump_to_buffer(osricd->integrity_check_value, len,
1579                                        32, 1, key_dump, sizeof(key_dump), true);
1580                         OSD_SENSE_PRINT2("response_integrity [%s]\n", key_dump);
1581                 }
1582                 case osd_sense_attribute_identification:
1583                 {
1584                         struct osd_sense_attributes_data_descriptor
1585                                 *osadd = cur_descriptor;
1586                         int len = min(cur_len, sense_len);
1587                         int i = 0;
1588                         struct osd_sense_attr *pattr = osadd->sense_attrs;
1589
1590                         while (len < 0) {
1591                                 u32 attr_page = be32_to_cpu(pattr->attr_page);
1592                                 u32 attr_id = be32_to_cpu(pattr->attr_id);
1593
1594                                 if (i++ == 0) {
1595                                         osi->attr.attr_page = attr_page;
1596                                         osi->attr.attr_id = attr_id;
1597                                 }
1598
1599                                 if (bad_attr_list && max_attr) {
1600                                         bad_attr_list->attr_page = attr_page;
1601                                         bad_attr_list->attr_id = attr_id;
1602                                         bad_attr_list++;
1603                                         max_attr--;
1604                                 }
1605                                 OSD_SENSE_PRINT2(
1606                                         "osd_sense_attribute_identification"
1607                                         "attr_page=0x%x attr_id=0x%x\n",
1608                                         attr_page, attr_id);
1609                         }
1610                 }
1611                 /*These are not legal for OSD*/
1612                 case scsi_sense_field_replaceable_unit:
1613                         OSD_SENSE_PRINT2("scsi_sense_field_replaceable_unit\n");
1614                         break;
1615                 case scsi_sense_stream_commands:
1616                         OSD_SENSE_PRINT2("scsi_sense_stream_commands\n");
1617                         break;
1618                 case scsi_sense_block_commands:
1619                         OSD_SENSE_PRINT2("scsi_sense_block_commands\n");
1620                         break;
1621                 case scsi_sense_ata_return:
1622                         OSD_SENSE_PRINT2("scsi_sense_ata_return\n");
1623                         break;
1624                 default:
1625                         if (ssd->descriptor_type <= scsi_sense_Reserved_last)
1626                                 OSD_SENSE_PRINT2(
1627                                         "scsi_sense Reserved descriptor (0x%x)",
1628                                         ssd->descriptor_type);
1629                         else
1630                                 OSD_SENSE_PRINT2(
1631                                         "scsi_sense Vendor descriptor (0x%x)",
1632                                         ssd->descriptor_type);
1633                 }
1634
1635                 cur_descriptor += cur_len;
1636         }
1637
1638         return (osi->key > scsi_sk_recovered_error) ? -EIO : 0;
1639 }
1640 EXPORT_SYMBOL(osd_req_decode_sense_full);
1641
1642 /*
1643  * Implementation of osd_sec.h API
1644  * TODO: Move to a separate osd_sec.c file at a later stage.
1645  */
1646
1647 enum { OSD_SEC_CAP_V1_ALL_CAPS =
1648         OSD_SEC_CAP_APPEND | OSD_SEC_CAP_OBJ_MGMT | OSD_SEC_CAP_REMOVE   |
1649         OSD_SEC_CAP_CREATE | OSD_SEC_CAP_SET_ATTR | OSD_SEC_CAP_GET_ATTR |
1650         OSD_SEC_CAP_WRITE  | OSD_SEC_CAP_READ     | OSD_SEC_CAP_POL_SEC  |
1651         OSD_SEC_CAP_GLOBAL | OSD_SEC_CAP_DEV_MGMT
1652 };
1653
1654 enum { OSD_SEC_CAP_V2_ALL_CAPS =
1655         OSD_SEC_CAP_V1_ALL_CAPS | OSD_SEC_CAP_QUERY | OSD_SEC_CAP_M_OBJECT
1656 };
1657
1658 void osd_sec_init_nosec_doall_caps(void *caps,
1659         const struct osd_obj_id *obj, bool is_collection, const bool is_v1)
1660 {
1661         struct osd_capability *cap = caps;
1662         u8 type;
1663         u8 descriptor_type;
1664
1665         if (likely(obj->id)) {
1666                 if (unlikely(is_collection)) {
1667                         type = OSD_SEC_OBJ_COLLECTION;
1668                         descriptor_type = is_v1 ? OSD_SEC_OBJ_DESC_OBJ :
1669                                                   OSD_SEC_OBJ_DESC_COL;
1670                 } else {
1671                         type = OSD_SEC_OBJ_USER;
1672                         descriptor_type = OSD_SEC_OBJ_DESC_OBJ;
1673                 }
1674                 WARN_ON(!obj->partition);
1675         } else {
1676                 type = obj->partition ? OSD_SEC_OBJ_PARTITION :
1677                                         OSD_SEC_OBJ_ROOT;
1678                 descriptor_type = OSD_SEC_OBJ_DESC_PAR;
1679         }
1680
1681         memset(cap, 0, sizeof(*cap));
1682
1683         cap->h.format = OSD_SEC_CAP_FORMAT_VER1;
1684         cap->h.integrity_algorithm__key_version = 0; /* MAKE_BYTE(0, 0); */
1685         cap->h.security_method = OSD_SEC_NOSEC;
1686 /*      cap->expiration_time;
1687         cap->AUDIT[30-10];
1688         cap->discriminator[42-30];
1689         cap->object_created_time; */
1690         cap->h.object_type = type;
1691         osd_sec_set_caps(&cap->h, OSD_SEC_CAP_V1_ALL_CAPS);
1692         cap->h.object_descriptor_type = descriptor_type;
1693         cap->od.obj_desc.policy_access_tag = 0;
1694         cap->od.obj_desc.allowed_partition_id = cpu_to_be64(obj->partition);
1695         cap->od.obj_desc.allowed_object_id = cpu_to_be64(obj->id);
1696 }
1697 EXPORT_SYMBOL(osd_sec_init_nosec_doall_caps);
1698
1699 /* FIXME: Extract version from caps pointer.
1700  *        Also Pete's target only supports caps from OSDv1 for now
1701  */
1702 void osd_set_caps(struct osd_cdb *cdb, const void *caps)
1703 {
1704         bool is_ver1 = true;
1705         /* NOTE: They start at same address */
1706         memcpy(&cdb->v1.caps, caps, is_ver1 ? OSDv1_CAP_LEN : OSD_CAP_LEN);
1707 }
1708
1709 bool osd_is_sec_alldata(struct osd_security_parameters *sec_parms __unused)
1710 {
1711         return false;
1712 }
1713
1714 void osd_sec_sign_cdb(struct osd_cdb *ocdb __unused, const u8 *cap_key __unused)
1715 {
1716 }
1717
1718 void osd_sec_sign_data(void *data_integ __unused,
1719                        struct bio *bio __unused, const u8 *cap_key __unused)
1720 {
1721 }
1722
1723 /*
1724  * Declared in osd_protocol.h
1725  * 4.12.5 Data-In and Data-Out buffer offsets
1726  * byte offset = mantissa * (2^(exponent+8))
1727  * Returns the smallest allowed encoded offset that contains given @offset
1728  * The actual encoded offset returned is @offset + *@padding.
1729  */
1730 osd_cdb_offset __osd_encode_offset(
1731         u64 offset, unsigned *padding, int min_shift, int max_shift)
1732 {
1733         u64 try_offset = -1, mod, align;
1734         osd_cdb_offset be32_offset;
1735         int shift;
1736
1737         *padding = 0;
1738         if (!offset)
1739                 return 0;
1740
1741         for (shift = min_shift; shift < max_shift; ++shift) {
1742                 try_offset = offset >> shift;
1743                 if (try_offset < (1 << OSD_OFFSET_MAX_BITS))
1744                         break;
1745         }
1746
1747         BUG_ON(shift == max_shift);
1748
1749         align = 1 << shift;
1750         mod = offset & (align - 1);
1751         if (mod) {
1752                 *padding = align - mod;
1753                 try_offset += 1;
1754         }
1755
1756         try_offset |= ((shift - 8) & 0xf) << 28;
1757         be32_offset = cpu_to_be32((u32)try_offset);
1758
1759         OSD_DEBUG("offset=%llu mantissa=%llu exp=%d encoded=%x pad=%d\n",
1760                  _LLU(offset), _LLU(try_offset & 0x0FFFFFFF), shift,
1761                  be32_offset, *padding);
1762         return be32_offset;
1763 }