linux/drivers/crypto/nx/nx-common-pseries.c
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   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Driver for IBM Power 842 compression accelerator
   4 *
   5 * Copyright (C) IBM Corporation, 2012
   6 *
   7 * Authors: Robert Jennings <rcj@linux.vnet.ibm.com>
   8 *          Seth Jennings <sjenning@linux.vnet.ibm.com>
   9 */
  10
  11#include <asm/vio.h>
  12#include <asm/hvcall.h>
  13#include <asm/vas.h>
  14
  15#include "nx-842.h"
  16#include "nx_csbcpb.h" /* struct nx_csbcpb */
  17
  18MODULE_LICENSE("GPL");
  19MODULE_AUTHOR("Robert Jennings <rcj@linux.vnet.ibm.com>");
  20MODULE_DESCRIPTION("842 H/W Compression driver for IBM Power processors");
  21MODULE_ALIAS_CRYPTO("842");
  22MODULE_ALIAS_CRYPTO("842-nx");
  23
  24/*
  25 * Coprocessor type specific capabilities from the hypervisor.
  26 */
  27struct hv_nx_cop_caps {
  28        __be64  descriptor;
  29        __be64  req_max_processed_len;  /* Max bytes in one GZIP request */
  30        __be64  min_compress_len;       /* Min compression size in bytes */
  31        __be64  min_decompress_len;     /* Min decompression size in bytes */
  32} __packed __aligned(0x1000);
  33
  34/*
  35 * Coprocessor type specific capabilities.
  36 */
  37struct nx_cop_caps {
  38        u64     descriptor;
  39        u64     req_max_processed_len;  /* Max bytes in one GZIP request */
  40        u64     min_compress_len;       /* Min compression in bytes */
  41        u64     min_decompress_len;     /* Min decompression in bytes */
  42};
  43
  44static u64 caps_feat;
  45static struct nx_cop_caps nx_cop_caps;
  46
  47static struct nx842_constraints nx842_pseries_constraints = {
  48        .alignment =    DDE_BUFFER_ALIGN,
  49        .multiple =     DDE_BUFFER_LAST_MULT,
  50        .minimum =      DDE_BUFFER_LAST_MULT,
  51        .maximum =      PAGE_SIZE, /* dynamic, max_sync_size */
  52};
  53
  54static int check_constraints(unsigned long buf, unsigned int *len, bool in)
  55{
  56        if (!IS_ALIGNED(buf, nx842_pseries_constraints.alignment)) {
  57                pr_debug("%s buffer 0x%lx not aligned to 0x%x\n",
  58                         in ? "input" : "output", buf,
  59                         nx842_pseries_constraints.alignment);
  60                return -EINVAL;
  61        }
  62        if (*len % nx842_pseries_constraints.multiple) {
  63                pr_debug("%s buffer len 0x%x not multiple of 0x%x\n",
  64                         in ? "input" : "output", *len,
  65                         nx842_pseries_constraints.multiple);
  66                if (in)
  67                        return -EINVAL;
  68                *len = round_down(*len, nx842_pseries_constraints.multiple);
  69        }
  70        if (*len < nx842_pseries_constraints.minimum) {
  71                pr_debug("%s buffer len 0x%x under minimum 0x%x\n",
  72                         in ? "input" : "output", *len,
  73                         nx842_pseries_constraints.minimum);
  74                return -EINVAL;
  75        }
  76        if (*len > nx842_pseries_constraints.maximum) {
  77                pr_debug("%s buffer len 0x%x over maximum 0x%x\n",
  78                         in ? "input" : "output", *len,
  79                         nx842_pseries_constraints.maximum);
  80                if (in)
  81                        return -EINVAL;
  82                *len = nx842_pseries_constraints.maximum;
  83        }
  84        return 0;
  85}
  86
  87/* I assume we need to align the CSB? */
  88#define WORKMEM_ALIGN   (256)
  89
  90struct nx842_workmem {
  91        /* scatterlist */
  92        char slin[4096];
  93        char slout[4096];
  94        /* coprocessor status/parameter block */
  95        struct nx_csbcpb csbcpb;
  96
  97        char padding[WORKMEM_ALIGN];
  98} __aligned(WORKMEM_ALIGN);
  99
 100/* Macros for fields within nx_csbcpb */
 101/* Check the valid bit within the csbcpb valid field */
 102#define NX842_CSBCBP_VALID_CHK(x) (x & BIT_MASK(7))
 103
 104/* CE macros operate on the completion_extension field bits in the csbcpb.
 105 * CE0 0=full completion, 1=partial completion
 106 * CE1 0=CE0 indicates completion, 1=termination (output may be modified)
 107 * CE2 0=processed_bytes is source bytes, 1=processed_bytes is target bytes */
 108#define NX842_CSBCPB_CE0(x)     (x & BIT_MASK(7))
 109#define NX842_CSBCPB_CE1(x)     (x & BIT_MASK(6))
 110#define NX842_CSBCPB_CE2(x)     (x & BIT_MASK(5))
 111
 112/* The NX unit accepts data only on 4K page boundaries */
 113#define NX842_HW_PAGE_SIZE      (4096)
 114#define NX842_HW_PAGE_MASK      (~(NX842_HW_PAGE_SIZE-1))
 115
 116struct ibm_nx842_counters {
 117        atomic64_t comp_complete;
 118        atomic64_t comp_failed;
 119        atomic64_t decomp_complete;
 120        atomic64_t decomp_failed;
 121        atomic64_t swdecomp;
 122        atomic64_t comp_times[32];
 123        atomic64_t decomp_times[32];
 124};
 125
 126static struct nx842_devdata {
 127        struct vio_dev *vdev;
 128        struct device *dev;
 129        struct ibm_nx842_counters *counters;
 130        unsigned int max_sg_len;
 131        unsigned int max_sync_size;
 132        unsigned int max_sync_sg;
 133} __rcu *devdata;
 134static DEFINE_SPINLOCK(devdata_mutex);
 135
 136#define NX842_COUNTER_INC(_x) \
 137static inline void nx842_inc_##_x( \
 138        const struct nx842_devdata *dev) { \
 139        if (dev) \
 140                atomic64_inc(&dev->counters->_x); \
 141}
 142NX842_COUNTER_INC(comp_complete);
 143NX842_COUNTER_INC(comp_failed);
 144NX842_COUNTER_INC(decomp_complete);
 145NX842_COUNTER_INC(decomp_failed);
 146NX842_COUNTER_INC(swdecomp);
 147
 148#define NX842_HIST_SLOTS 16
 149
 150static void ibm_nx842_incr_hist(atomic64_t *times, unsigned int time)
 151{
 152        int bucket = fls(time);
 153
 154        if (bucket)
 155                bucket = min((NX842_HIST_SLOTS - 1), bucket - 1);
 156
 157        atomic64_inc(&times[bucket]);
 158}
 159
 160/* NX unit operation flags */
 161#define NX842_OP_COMPRESS       0x0
 162#define NX842_OP_CRC            0x1
 163#define NX842_OP_DECOMPRESS     0x2
 164#define NX842_OP_COMPRESS_CRC   (NX842_OP_COMPRESS | NX842_OP_CRC)
 165#define NX842_OP_DECOMPRESS_CRC (NX842_OP_DECOMPRESS | NX842_OP_CRC)
 166#define NX842_OP_ASYNC          (1<<23)
 167#define NX842_OP_NOTIFY         (1<<22)
 168#define NX842_OP_NOTIFY_INT(x)  ((x & 0xff)<<8)
 169
 170static unsigned long nx842_get_desired_dma(struct vio_dev *viodev)
 171{
 172        /* No use of DMA mappings within the driver. */
 173        return 0;
 174}
 175
 176struct nx842_slentry {
 177        __be64 ptr; /* Real address (use __pa()) */
 178        __be64 len;
 179};
 180
 181/* pHyp scatterlist entry */
 182struct nx842_scatterlist {
 183        int entry_nr; /* number of slentries */
 184        struct nx842_slentry *entries; /* ptr to array of slentries */
 185};
 186
 187/* Does not include sizeof(entry_nr) in the size */
 188static inline unsigned long nx842_get_scatterlist_size(
 189                                struct nx842_scatterlist *sl)
 190{
 191        return sl->entry_nr * sizeof(struct nx842_slentry);
 192}
 193
 194static int nx842_build_scatterlist(unsigned long buf, int len,
 195                        struct nx842_scatterlist *sl)
 196{
 197        unsigned long entrylen;
 198        struct nx842_slentry *entry;
 199
 200        sl->entry_nr = 0;
 201
 202        entry = sl->entries;
 203        while (len) {
 204                entry->ptr = cpu_to_be64(nx842_get_pa((void *)buf));
 205                entrylen = min_t(int, len,
 206                                 LEN_ON_SIZE(buf, NX842_HW_PAGE_SIZE));
 207                entry->len = cpu_to_be64(entrylen);
 208
 209                len -= entrylen;
 210                buf += entrylen;
 211
 212                sl->entry_nr++;
 213                entry++;
 214        }
 215
 216        return 0;
 217}
 218
 219static int nx842_validate_result(struct device *dev,
 220        struct cop_status_block *csb)
 221{
 222        /* The csb must be valid after returning from vio_h_cop_sync */
 223        if (!NX842_CSBCBP_VALID_CHK(csb->valid)) {
 224                dev_err(dev, "%s: cspcbp not valid upon completion.\n",
 225                                __func__);
 226                dev_dbg(dev, "valid:0x%02x cs:0x%02x cc:0x%02x ce:0x%02x\n",
 227                                csb->valid,
 228                                csb->crb_seq_number,
 229                                csb->completion_code,
 230                                csb->completion_extension);
 231                dev_dbg(dev, "processed_bytes:%d address:0x%016lx\n",
 232                                be32_to_cpu(csb->processed_byte_count),
 233                                (unsigned long)be64_to_cpu(csb->address));
 234                return -EIO;
 235        }
 236
 237        /* Check return values from the hardware in the CSB */
 238        switch (csb->completion_code) {
 239        case 0: /* Completed without error */
 240                break;
 241        case 64: /* Compression ok, but output larger than input */
 242                dev_dbg(dev, "%s: output size larger than input size\n",
 243                                        __func__);
 244                break;
 245        case 13: /* Output buffer too small */
 246                dev_dbg(dev, "%s: Out of space in output buffer\n",
 247                                        __func__);
 248                return -ENOSPC;
 249        case 65: /* Calculated CRC doesn't match the passed value */
 250                dev_dbg(dev, "%s: CRC mismatch for decompression\n",
 251                                        __func__);
 252                return -EINVAL;
 253        case 66: /* Input data contains an illegal template field */
 254        case 67: /* Template indicates data past the end of the input stream */
 255                dev_dbg(dev, "%s: Bad data for decompression (code:%d)\n",
 256                                        __func__, csb->completion_code);
 257                return -EINVAL;
 258        default:
 259                dev_dbg(dev, "%s: Unspecified error (code:%d)\n",
 260                                        __func__, csb->completion_code);
 261                return -EIO;
 262        }
 263
 264        /* Hardware sanity check */
 265        if (!NX842_CSBCPB_CE2(csb->completion_extension)) {
 266                dev_err(dev, "%s: No error returned by hardware, but "
 267                                "data returned is unusable, contact support.\n"
 268                                "(Additional info: csbcbp->processed bytes "
 269                                "does not specify processed bytes for the "
 270                                "target buffer.)\n", __func__);
 271                return -EIO;
 272        }
 273
 274        return 0;
 275}
 276
 277/**
 278 * nx842_pseries_compress - Compress data using the 842 algorithm
 279 *
 280 * Compression provide by the NX842 coprocessor on IBM Power systems.
 281 * The input buffer is compressed and the result is stored in the
 282 * provided output buffer.
 283 *
 284 * Upon return from this function @outlen contains the length of the
 285 * compressed data.  If there is an error then @outlen will be 0 and an
 286 * error will be specified by the return code from this function.
 287 *
 288 * @in: Pointer to input buffer
 289 * @inlen: Length of input buffer
 290 * @out: Pointer to output buffer
 291 * @outlen: Length of output buffer
 292 * @wmem: ptr to buffer for working memory, size determined by
 293 *        nx842_pseries_driver.workmem_size
 294 *
 295 * Returns:
 296 *   0          Success, output of length @outlen stored in the buffer at @out
 297 *   -ENOMEM    Unable to allocate internal buffers
 298 *   -ENOSPC    Output buffer is to small
 299 *   -EIO       Internal error
 300 *   -ENODEV    Hardware unavailable
 301 */
 302static int nx842_pseries_compress(const unsigned char *in, unsigned int inlen,
 303                                  unsigned char *out, unsigned int *outlen,
 304                                  void *wmem)
 305{
 306        struct nx842_devdata *local_devdata;
 307        struct device *dev = NULL;
 308        struct nx842_workmem *workmem;
 309        struct nx842_scatterlist slin, slout;
 310        struct nx_csbcpb *csbcpb;
 311        int ret = 0;
 312        unsigned long inbuf, outbuf;
 313        struct vio_pfo_op op = {
 314                .done = NULL,
 315                .handle = 0,
 316                .timeout = 0,
 317        };
 318        unsigned long start = get_tb();
 319
 320        inbuf = (unsigned long)in;
 321        if (check_constraints(inbuf, &inlen, true))
 322                return -EINVAL;
 323
 324        outbuf = (unsigned long)out;
 325        if (check_constraints(outbuf, outlen, false))
 326                return -EINVAL;
 327
 328        rcu_read_lock();
 329        local_devdata = rcu_dereference(devdata);
 330        if (!local_devdata || !local_devdata->dev) {
 331                rcu_read_unlock();
 332                return -ENODEV;
 333        }
 334        dev = local_devdata->dev;
 335
 336        /* Init scatterlist */
 337        workmem = PTR_ALIGN(wmem, WORKMEM_ALIGN);
 338        slin.entries = (struct nx842_slentry *)workmem->slin;
 339        slout.entries = (struct nx842_slentry *)workmem->slout;
 340
 341        /* Init operation */
 342        op.flags = NX842_OP_COMPRESS_CRC;
 343        csbcpb = &workmem->csbcpb;
 344        memset(csbcpb, 0, sizeof(*csbcpb));
 345        op.csbcpb = nx842_get_pa(csbcpb);
 346
 347        if ((inbuf & NX842_HW_PAGE_MASK) ==
 348            ((inbuf + inlen - 1) & NX842_HW_PAGE_MASK)) {
 349                /* Create direct DDE */
 350                op.in = nx842_get_pa((void *)inbuf);
 351                op.inlen = inlen;
 352        } else {
 353                /* Create indirect DDE (scatterlist) */
 354                nx842_build_scatterlist(inbuf, inlen, &slin);
 355                op.in = nx842_get_pa(slin.entries);
 356                op.inlen = -nx842_get_scatterlist_size(&slin);
 357        }
 358
 359        if ((outbuf & NX842_HW_PAGE_MASK) ==
 360            ((outbuf + *outlen - 1) & NX842_HW_PAGE_MASK)) {
 361                /* Create direct DDE */
 362                op.out = nx842_get_pa((void *)outbuf);
 363                op.outlen = *outlen;
 364        } else {
 365                /* Create indirect DDE (scatterlist) */
 366                nx842_build_scatterlist(outbuf, *outlen, &slout);
 367                op.out = nx842_get_pa(slout.entries);
 368                op.outlen = -nx842_get_scatterlist_size(&slout);
 369        }
 370
 371        dev_dbg(dev, "%s: op.in %lx op.inlen %ld op.out %lx op.outlen %ld\n",
 372                __func__, (unsigned long)op.in, (long)op.inlen,
 373                (unsigned long)op.out, (long)op.outlen);
 374
 375        /* Send request to pHyp */
 376        ret = vio_h_cop_sync(local_devdata->vdev, &op);
 377
 378        /* Check for pHyp error */
 379        if (ret) {
 380                dev_dbg(dev, "%s: vio_h_cop_sync error (ret=%d, hret=%ld)\n",
 381                        __func__, ret, op.hcall_err);
 382                ret = -EIO;
 383                goto unlock;
 384        }
 385
 386        /* Check for hardware error */
 387        ret = nx842_validate_result(dev, &csbcpb->csb);
 388        if (ret)
 389                goto unlock;
 390
 391        *outlen = be32_to_cpu(csbcpb->csb.processed_byte_count);
 392        dev_dbg(dev, "%s: processed_bytes=%d\n", __func__, *outlen);
 393
 394unlock:
 395        if (ret)
 396                nx842_inc_comp_failed(local_devdata);
 397        else {
 398                nx842_inc_comp_complete(local_devdata);
 399                ibm_nx842_incr_hist(local_devdata->counters->comp_times,
 400                        (get_tb() - start) / tb_ticks_per_usec);
 401        }
 402        rcu_read_unlock();
 403        return ret;
 404}
 405
 406/**
 407 * nx842_pseries_decompress - Decompress data using the 842 algorithm
 408 *
 409 * Decompression provide by the NX842 coprocessor on IBM Power systems.
 410 * The input buffer is decompressed and the result is stored in the
 411 * provided output buffer.  The size allocated to the output buffer is
 412 * provided by the caller of this function in @outlen.  Upon return from
 413 * this function @outlen contains the length of the decompressed data.
 414 * If there is an error then @outlen will be 0 and an error will be
 415 * specified by the return code from this function.
 416 *
 417 * @in: Pointer to input buffer
 418 * @inlen: Length of input buffer
 419 * @out: Pointer to output buffer
 420 * @outlen: Length of output buffer
 421 * @wmem: ptr to buffer for working memory, size determined by
 422 *        nx842_pseries_driver.workmem_size
 423 *
 424 * Returns:
 425 *   0          Success, output of length @outlen stored in the buffer at @out
 426 *   -ENODEV    Hardware decompression device is unavailable
 427 *   -ENOMEM    Unable to allocate internal buffers
 428 *   -ENOSPC    Output buffer is to small
 429 *   -EINVAL    Bad input data encountered when attempting decompress
 430 *   -EIO       Internal error
 431 */
 432static int nx842_pseries_decompress(const unsigned char *in, unsigned int inlen,
 433                                    unsigned char *out, unsigned int *outlen,
 434                                    void *wmem)
 435{
 436        struct nx842_devdata *local_devdata;
 437        struct device *dev = NULL;
 438        struct nx842_workmem *workmem;
 439        struct nx842_scatterlist slin, slout;
 440        struct nx_csbcpb *csbcpb;
 441        int ret = 0;
 442        unsigned long inbuf, outbuf;
 443        struct vio_pfo_op op = {
 444                .done = NULL,
 445                .handle = 0,
 446                .timeout = 0,
 447        };
 448        unsigned long start = get_tb();
 449
 450        /* Ensure page alignment and size */
 451        inbuf = (unsigned long)in;
 452        if (check_constraints(inbuf, &inlen, true))
 453                return -EINVAL;
 454
 455        outbuf = (unsigned long)out;
 456        if (check_constraints(outbuf, outlen, false))
 457                return -EINVAL;
 458
 459        rcu_read_lock();
 460        local_devdata = rcu_dereference(devdata);
 461        if (!local_devdata || !local_devdata->dev) {
 462                rcu_read_unlock();
 463                return -ENODEV;
 464        }
 465        dev = local_devdata->dev;
 466
 467        workmem = PTR_ALIGN(wmem, WORKMEM_ALIGN);
 468
 469        /* Init scatterlist */
 470        slin.entries = (struct nx842_slentry *)workmem->slin;
 471        slout.entries = (struct nx842_slentry *)workmem->slout;
 472
 473        /* Init operation */
 474        op.flags = NX842_OP_DECOMPRESS_CRC;
 475        csbcpb = &workmem->csbcpb;
 476        memset(csbcpb, 0, sizeof(*csbcpb));
 477        op.csbcpb = nx842_get_pa(csbcpb);
 478
 479        if ((inbuf & NX842_HW_PAGE_MASK) ==
 480            ((inbuf + inlen - 1) & NX842_HW_PAGE_MASK)) {
 481                /* Create direct DDE */
 482                op.in = nx842_get_pa((void *)inbuf);
 483                op.inlen = inlen;
 484        } else {
 485                /* Create indirect DDE (scatterlist) */
 486                nx842_build_scatterlist(inbuf, inlen, &slin);
 487                op.in = nx842_get_pa(slin.entries);
 488                op.inlen = -nx842_get_scatterlist_size(&slin);
 489        }
 490
 491        if ((outbuf & NX842_HW_PAGE_MASK) ==
 492            ((outbuf + *outlen - 1) & NX842_HW_PAGE_MASK)) {
 493                /* Create direct DDE */
 494                op.out = nx842_get_pa((void *)outbuf);
 495                op.outlen = *outlen;
 496        } else {
 497                /* Create indirect DDE (scatterlist) */
 498                nx842_build_scatterlist(outbuf, *outlen, &slout);
 499                op.out = nx842_get_pa(slout.entries);
 500                op.outlen = -nx842_get_scatterlist_size(&slout);
 501        }
 502
 503        dev_dbg(dev, "%s: op.in %lx op.inlen %ld op.out %lx op.outlen %ld\n",
 504                __func__, (unsigned long)op.in, (long)op.inlen,
 505                (unsigned long)op.out, (long)op.outlen);
 506
 507        /* Send request to pHyp */
 508        ret = vio_h_cop_sync(local_devdata->vdev, &op);
 509
 510        /* Check for pHyp error */
 511        if (ret) {
 512                dev_dbg(dev, "%s: vio_h_cop_sync error (ret=%d, hret=%ld)\n",
 513                        __func__, ret, op.hcall_err);
 514                goto unlock;
 515        }
 516
 517        /* Check for hardware error */
 518        ret = nx842_validate_result(dev, &csbcpb->csb);
 519        if (ret)
 520                goto unlock;
 521
 522        *outlen = be32_to_cpu(csbcpb->csb.processed_byte_count);
 523
 524unlock:
 525        if (ret)
 526                /* decompress fail */
 527                nx842_inc_decomp_failed(local_devdata);
 528        else {
 529                nx842_inc_decomp_complete(local_devdata);
 530                ibm_nx842_incr_hist(local_devdata->counters->decomp_times,
 531                        (get_tb() - start) / tb_ticks_per_usec);
 532        }
 533
 534        rcu_read_unlock();
 535        return ret;
 536}
 537
 538/**
 539 * nx842_OF_set_defaults -- Set default (disabled) values for devdata
 540 *
 541 * @devdata: struct nx842_devdata to update
 542 *
 543 * Returns:
 544 *  0 on success
 545 *  -ENOENT if @devdata ptr is NULL
 546 */
 547static int nx842_OF_set_defaults(struct nx842_devdata *devdata)
 548{
 549        if (devdata) {
 550                devdata->max_sync_size = 0;
 551                devdata->max_sync_sg = 0;
 552                devdata->max_sg_len = 0;
 553                return 0;
 554        } else
 555                return -ENOENT;
 556}
 557
 558/**
 559 * nx842_OF_upd_status -- Check the device info from OF status prop
 560 *
 561 * The status property indicates if the accelerator is enabled.  If the
 562 * device is in the OF tree it indicates that the hardware is present.
 563 * The status field indicates if the device is enabled when the status
 564 * is 'okay'.  Otherwise the device driver will be disabled.
 565 *
 566 * @devdata: struct nx842_devdata to use for dev_info
 567 * @prop: struct property point containing the maxsyncop for the update
 568 *
 569 * Returns:
 570 *  0 - Device is available
 571 *  -ENODEV - Device is not available
 572 */
 573static int nx842_OF_upd_status(struct nx842_devdata *devdata,
 574                               struct property *prop)
 575{
 576        const char *status = (const char *)prop->value;
 577
 578        if (!strncmp(status, "okay", (size_t)prop->length))
 579                return 0;
 580        if (!strncmp(status, "disabled", (size_t)prop->length))
 581                return -ENODEV;
 582        dev_info(devdata->dev, "%s: unknown status '%s'\n", __func__, status);
 583
 584        return -EINVAL;
 585}
 586
 587/**
 588 * nx842_OF_upd_maxsglen -- Update the device info from OF maxsglen prop
 589 *
 590 * Definition of the 'ibm,max-sg-len' OF property:
 591 *  This field indicates the maximum byte length of a scatter list
 592 *  for the platform facility. It is a single cell encoded as with encode-int.
 593 *
 594 * Example:
 595 *  # od -x ibm,max-sg-len
 596 *  0000000 0000 0ff0
 597 *
 598 *  In this example, the maximum byte length of a scatter list is
 599 *  0x0ff0 (4,080).
 600 *
 601 * @devdata: struct nx842_devdata to update
 602 * @prop: struct property point containing the maxsyncop for the update
 603 *
 604 * Returns:
 605 *  0 on success
 606 *  -EINVAL on failure
 607 */
 608static int nx842_OF_upd_maxsglen(struct nx842_devdata *devdata,
 609                                        struct property *prop) {
 610        int ret = 0;
 611        const unsigned int maxsglen = of_read_number(prop->value, 1);
 612
 613        if (prop->length != sizeof(maxsglen)) {
 614                dev_err(devdata->dev, "%s: unexpected format for ibm,max-sg-len property\n", __func__);
 615                dev_dbg(devdata->dev, "%s: ibm,max-sg-len is %d bytes long, expected %lu bytes\n", __func__,
 616                                prop->length, sizeof(maxsglen));
 617                ret = -EINVAL;
 618        } else {
 619                devdata->max_sg_len = min_t(unsigned int,
 620                                            maxsglen, NX842_HW_PAGE_SIZE);
 621        }
 622
 623        return ret;
 624}
 625
 626/**
 627 * nx842_OF_upd_maxsyncop -- Update the device info from OF maxsyncop prop
 628 *
 629 * Definition of the 'ibm,max-sync-cop' OF property:
 630 *  Two series of cells.  The first series of cells represents the maximums
 631 *  that can be synchronously compressed. The second series of cells
 632 *  represents the maximums that can be synchronously decompressed.
 633 *  1. The first cell in each series contains the count of the number of
 634 *     data length, scatter list elements pairs that follow – each being
 635 *     of the form
 636 *    a. One cell data byte length
 637 *    b. One cell total number of scatter list elements
 638 *
 639 * Example:
 640 *  # od -x ibm,max-sync-cop
 641 *  0000000 0000 0001 0000 1000 0000 01fe 0000 0001
 642 *  0000020 0000 1000 0000 01fe
 643 *
 644 *  In this example, compression supports 0x1000 (4,096) data byte length
 645 *  and 0x1fe (510) total scatter list elements.  Decompression supports
 646 *  0x1000 (4,096) data byte length and 0x1f3 (510) total scatter list
 647 *  elements.
 648 *
 649 * @devdata: struct nx842_devdata to update
 650 * @prop: struct property point containing the maxsyncop for the update
 651 *
 652 * Returns:
 653 *  0 on success
 654 *  -EINVAL on failure
 655 */
 656static int nx842_OF_upd_maxsyncop(struct nx842_devdata *devdata,
 657                                        struct property *prop) {
 658        int ret = 0;
 659        unsigned int comp_data_limit, decomp_data_limit;
 660        unsigned int comp_sg_limit, decomp_sg_limit;
 661        const struct maxsynccop_t {
 662                __be32 comp_elements;
 663                __be32 comp_data_limit;
 664                __be32 comp_sg_limit;
 665                __be32 decomp_elements;
 666                __be32 decomp_data_limit;
 667                __be32 decomp_sg_limit;
 668        } *maxsynccop;
 669
 670        if (prop->length != sizeof(*maxsynccop)) {
 671                dev_err(devdata->dev, "%s: unexpected format for ibm,max-sync-cop property\n", __func__);
 672                dev_dbg(devdata->dev, "%s: ibm,max-sync-cop is %d bytes long, expected %lu bytes\n", __func__, prop->length,
 673                                sizeof(*maxsynccop));
 674                ret = -EINVAL;
 675                goto out;
 676        }
 677
 678        maxsynccop = (const struct maxsynccop_t *)prop->value;
 679        comp_data_limit = be32_to_cpu(maxsynccop->comp_data_limit);
 680        comp_sg_limit = be32_to_cpu(maxsynccop->comp_sg_limit);
 681        decomp_data_limit = be32_to_cpu(maxsynccop->decomp_data_limit);
 682        decomp_sg_limit = be32_to_cpu(maxsynccop->decomp_sg_limit);
 683
 684        /* Use one limit rather than separate limits for compression and
 685         * decompression. Set a maximum for this so as not to exceed the
 686         * size that the header can support and round the value down to
 687         * the hardware page size (4K) */
 688        devdata->max_sync_size = min(comp_data_limit, decomp_data_limit);
 689
 690        devdata->max_sync_size = min_t(unsigned int, devdata->max_sync_size,
 691                                        65536);
 692
 693        if (devdata->max_sync_size < 4096) {
 694                dev_err(devdata->dev, "%s: hardware max data size (%u) is "
 695                                "less than the driver minimum, unable to use "
 696                                "the hardware device\n",
 697                                __func__, devdata->max_sync_size);
 698                ret = -EINVAL;
 699                goto out;
 700        }
 701
 702        nx842_pseries_constraints.maximum = devdata->max_sync_size;
 703
 704        devdata->max_sync_sg = min(comp_sg_limit, decomp_sg_limit);
 705        if (devdata->max_sync_sg < 1) {
 706                dev_err(devdata->dev, "%s: hardware max sg size (%u) is "
 707                                "less than the driver minimum, unable to use "
 708                                "the hardware device\n",
 709                                __func__, devdata->max_sync_sg);
 710                ret = -EINVAL;
 711                goto out;
 712        }
 713
 714out:
 715        return ret;
 716}
 717
 718/**
 719 * nx842_OF_upd -- Handle OF properties updates for the device.
 720 *
 721 * Set all properties from the OF tree.  Optionally, a new property
 722 * can be provided by the @new_prop pointer to overwrite an existing value.
 723 * The device will remain disabled until all values are valid, this function
 724 * will return an error for updates unless all values are valid.
 725 *
 726 * @new_prop: If not NULL, this property is being updated.  If NULL, update
 727 *  all properties from the current values in the OF tree.
 728 *
 729 * Returns:
 730 *  0 - Success
 731 *  -ENOMEM - Could not allocate memory for new devdata structure
 732 *  -EINVAL - property value not found, new_prop is not a recognized
 733 *      property for the device or property value is not valid.
 734 *  -ENODEV - Device is not available
 735 */
 736static int nx842_OF_upd(struct property *new_prop)
 737{
 738        struct nx842_devdata *old_devdata = NULL;
 739        struct nx842_devdata *new_devdata = NULL;
 740        struct device_node *of_node = NULL;
 741        struct property *status = NULL;
 742        struct property *maxsglen = NULL;
 743        struct property *maxsyncop = NULL;
 744        int ret = 0;
 745        unsigned long flags;
 746
 747        new_devdata = kzalloc(sizeof(*new_devdata), GFP_NOFS);
 748        if (!new_devdata)
 749                return -ENOMEM;
 750
 751        spin_lock_irqsave(&devdata_mutex, flags);
 752        old_devdata = rcu_dereference_check(devdata,
 753                        lockdep_is_held(&devdata_mutex));
 754        if (old_devdata)
 755                of_node = old_devdata->dev->of_node;
 756
 757        if (!old_devdata || !of_node) {
 758                pr_err("%s: device is not available\n", __func__);
 759                spin_unlock_irqrestore(&devdata_mutex, flags);
 760                kfree(new_devdata);
 761                return -ENODEV;
 762        }
 763
 764        memcpy(new_devdata, old_devdata, sizeof(*old_devdata));
 765        new_devdata->counters = old_devdata->counters;
 766
 767        /* Set ptrs for existing properties */
 768        status = of_find_property(of_node, "status", NULL);
 769        maxsglen = of_find_property(of_node, "ibm,max-sg-len", NULL);
 770        maxsyncop = of_find_property(of_node, "ibm,max-sync-cop", NULL);
 771        if (!status || !maxsglen || !maxsyncop) {
 772                dev_err(old_devdata->dev, "%s: Could not locate device properties\n", __func__);
 773                ret = -EINVAL;
 774                goto error_out;
 775        }
 776
 777        /*
 778         * If this is a property update, there are only certain properties that
 779         * we care about. Bail if it isn't in the below list
 780         */
 781        if (new_prop && (strncmp(new_prop->name, "status", new_prop->length) ||
 782                         strncmp(new_prop->name, "ibm,max-sg-len", new_prop->length) ||
 783                         strncmp(new_prop->name, "ibm,max-sync-cop", new_prop->length)))
 784                goto out;
 785
 786        /* Perform property updates */
 787        ret = nx842_OF_upd_status(new_devdata, status);
 788        if (ret)
 789                goto error_out;
 790
 791        ret = nx842_OF_upd_maxsglen(new_devdata, maxsglen);
 792        if (ret)
 793                goto error_out;
 794
 795        ret = nx842_OF_upd_maxsyncop(new_devdata, maxsyncop);
 796        if (ret)
 797                goto error_out;
 798
 799out:
 800        dev_info(old_devdata->dev, "%s: max_sync_size new:%u old:%u\n",
 801                        __func__, new_devdata->max_sync_size,
 802                        old_devdata->max_sync_size);
 803        dev_info(old_devdata->dev, "%s: max_sync_sg new:%u old:%u\n",
 804                        __func__, new_devdata->max_sync_sg,
 805                        old_devdata->max_sync_sg);
 806        dev_info(old_devdata->dev, "%s: max_sg_len new:%u old:%u\n",
 807                        __func__, new_devdata->max_sg_len,
 808                        old_devdata->max_sg_len);
 809
 810        rcu_assign_pointer(devdata, new_devdata);
 811        spin_unlock_irqrestore(&devdata_mutex, flags);
 812        synchronize_rcu();
 813        dev_set_drvdata(new_devdata->dev, new_devdata);
 814        kfree(old_devdata);
 815        return 0;
 816
 817error_out:
 818        if (new_devdata) {
 819                dev_info(old_devdata->dev, "%s: device disabled\n", __func__);
 820                nx842_OF_set_defaults(new_devdata);
 821                rcu_assign_pointer(devdata, new_devdata);
 822                spin_unlock_irqrestore(&devdata_mutex, flags);
 823                synchronize_rcu();
 824                dev_set_drvdata(new_devdata->dev, new_devdata);
 825                kfree(old_devdata);
 826        } else {
 827                dev_err(old_devdata->dev, "%s: could not update driver from hardware\n", __func__);
 828                spin_unlock_irqrestore(&devdata_mutex, flags);
 829        }
 830
 831        if (!ret)
 832                ret = -EINVAL;
 833        return ret;
 834}
 835
 836/**
 837 * nx842_OF_notifier - Process updates to OF properties for the device
 838 *
 839 * @np: notifier block
 840 * @action: notifier action
 841 * @data: struct of_reconfig_data pointer
 842 *
 843 * Returns:
 844 *      NOTIFY_OK on success
 845 *      NOTIFY_BAD encoded with error number on failure, use
 846 *              notifier_to_errno() to decode this value
 847 */
 848static int nx842_OF_notifier(struct notifier_block *np, unsigned long action,
 849                             void *data)
 850{
 851        struct of_reconfig_data *upd = data;
 852        struct nx842_devdata *local_devdata;
 853        struct device_node *node = NULL;
 854
 855        rcu_read_lock();
 856        local_devdata = rcu_dereference(devdata);
 857        if (local_devdata)
 858                node = local_devdata->dev->of_node;
 859
 860        if (local_devdata &&
 861                        action == OF_RECONFIG_UPDATE_PROPERTY &&
 862                        !strcmp(upd->dn->name, node->name)) {
 863                rcu_read_unlock();
 864                nx842_OF_upd(upd->prop);
 865        } else
 866                rcu_read_unlock();
 867
 868        return NOTIFY_OK;
 869}
 870
 871static struct notifier_block nx842_of_nb = {
 872        .notifier_call = nx842_OF_notifier,
 873};
 874
 875#define nx842_counter_read(_name)                                       \
 876static ssize_t nx842_##_name##_show(struct device *dev,         \
 877                struct device_attribute *attr,                          \
 878                char *buf) {                                            \
 879        struct nx842_devdata *local_devdata;                    \
 880        int p = 0;                                                      \
 881        rcu_read_lock();                                                \
 882        local_devdata = rcu_dereference(devdata);                       \
 883        if (local_devdata)                                              \
 884                p = snprintf(buf, PAGE_SIZE, "%lld\n",                  \
 885                       atomic64_read(&local_devdata->counters->_name)); \
 886        rcu_read_unlock();                                              \
 887        return p;                                                       \
 888}
 889
 890#define NX842DEV_COUNTER_ATTR_RO(_name)                                 \
 891        nx842_counter_read(_name);                                      \
 892        static struct device_attribute dev_attr_##_name = __ATTR(_name, \
 893                                                0444,                   \
 894                                                nx842_##_name##_show,\
 895                                                NULL);
 896
 897NX842DEV_COUNTER_ATTR_RO(comp_complete);
 898NX842DEV_COUNTER_ATTR_RO(comp_failed);
 899NX842DEV_COUNTER_ATTR_RO(decomp_complete);
 900NX842DEV_COUNTER_ATTR_RO(decomp_failed);
 901NX842DEV_COUNTER_ATTR_RO(swdecomp);
 902
 903static ssize_t nx842_timehist_show(struct device *,
 904                struct device_attribute *, char *);
 905
 906static struct device_attribute dev_attr_comp_times = __ATTR(comp_times, 0444,
 907                nx842_timehist_show, NULL);
 908static struct device_attribute dev_attr_decomp_times = __ATTR(decomp_times,
 909                0444, nx842_timehist_show, NULL);
 910
 911static ssize_t nx842_timehist_show(struct device *dev,
 912                struct device_attribute *attr, char *buf) {
 913        char *p = buf;
 914        struct nx842_devdata *local_devdata;
 915        atomic64_t *times;
 916        int bytes_remain = PAGE_SIZE;
 917        int bytes;
 918        int i;
 919
 920        rcu_read_lock();
 921        local_devdata = rcu_dereference(devdata);
 922        if (!local_devdata) {
 923                rcu_read_unlock();
 924                return 0;
 925        }
 926
 927        if (attr == &dev_attr_comp_times)
 928                times = local_devdata->counters->comp_times;
 929        else if (attr == &dev_attr_decomp_times)
 930                times = local_devdata->counters->decomp_times;
 931        else {
 932                rcu_read_unlock();
 933                return 0;
 934        }
 935
 936        for (i = 0; i < (NX842_HIST_SLOTS - 2); i++) {
 937                bytes = snprintf(p, bytes_remain, "%u-%uus:\t%lld\n",
 938                               i ? (2<<(i-1)) : 0, (2<<i)-1,
 939                               atomic64_read(&times[i]));
 940                bytes_remain -= bytes;
 941                p += bytes;
 942        }
 943        /* The last bucket holds everything over
 944         * 2<<(NX842_HIST_SLOTS - 2) us */
 945        bytes = snprintf(p, bytes_remain, "%uus - :\t%lld\n",
 946                        2<<(NX842_HIST_SLOTS - 2),
 947                        atomic64_read(&times[(NX842_HIST_SLOTS - 1)]));
 948        p += bytes;
 949
 950        rcu_read_unlock();
 951        return p - buf;
 952}
 953
 954static struct attribute *nx842_sysfs_entries[] = {
 955        &dev_attr_comp_complete.attr,
 956        &dev_attr_comp_failed.attr,
 957        &dev_attr_decomp_complete.attr,
 958        &dev_attr_decomp_failed.attr,
 959        &dev_attr_swdecomp.attr,
 960        &dev_attr_comp_times.attr,
 961        &dev_attr_decomp_times.attr,
 962        NULL,
 963};
 964
 965static struct attribute_group nx842_attribute_group = {
 966        .name = NULL,           /* put in device directory */
 967        .attrs = nx842_sysfs_entries,
 968};
 969
 970#define nxcop_caps_read(_name)                                          \
 971static ssize_t nxcop_##_name##_show(struct device *dev,                 \
 972                        struct device_attribute *attr, char *buf)       \
 973{                                                                       \
 974        return sprintf(buf, "%lld\n", nx_cop_caps._name);               \
 975}
 976
 977#define NXCT_ATTR_RO(_name)                                             \
 978        nxcop_caps_read(_name);                                         \
 979        static struct device_attribute dev_attr_##_name = __ATTR(_name, \
 980                                                0444,                   \
 981                                                nxcop_##_name##_show,   \
 982                                                NULL);
 983
 984NXCT_ATTR_RO(req_max_processed_len);
 985NXCT_ATTR_RO(min_compress_len);
 986NXCT_ATTR_RO(min_decompress_len);
 987
 988static struct attribute *nxcop_caps_sysfs_entries[] = {
 989        &dev_attr_req_max_processed_len.attr,
 990        &dev_attr_min_compress_len.attr,
 991        &dev_attr_min_decompress_len.attr,
 992        NULL,
 993};
 994
 995static struct attribute_group nxcop_caps_attr_group = {
 996        .name   =       "nx_gzip_caps",
 997        .attrs  =       nxcop_caps_sysfs_entries,
 998};
 999
1000static struct nx842_driver nx842_pseries_driver = {
1001        .name =         KBUILD_MODNAME,
1002        .owner =        THIS_MODULE,
1003        .workmem_size = sizeof(struct nx842_workmem),
1004        .constraints =  &nx842_pseries_constraints,
1005        .compress =     nx842_pseries_compress,
1006        .decompress =   nx842_pseries_decompress,
1007};
1008
1009static int nx842_pseries_crypto_init(struct crypto_tfm *tfm)
1010{
1011        return nx842_crypto_init(tfm, &nx842_pseries_driver);
1012}
1013
1014static struct crypto_alg nx842_pseries_alg = {
1015        .cra_name               = "842",
1016        .cra_driver_name        = "842-nx",
1017        .cra_priority           = 300,
1018        .cra_flags              = CRYPTO_ALG_TYPE_COMPRESS,
1019        .cra_ctxsize            = sizeof(struct nx842_crypto_ctx),
1020        .cra_module             = THIS_MODULE,
1021        .cra_init               = nx842_pseries_crypto_init,
1022        .cra_exit               = nx842_crypto_exit,
1023        .cra_u                  = { .compress = {
1024        .coa_compress           = nx842_crypto_compress,
1025        .coa_decompress         = nx842_crypto_decompress } }
1026};
1027
1028static int nx842_probe(struct vio_dev *viodev,
1029                       const struct vio_device_id *id)
1030{
1031        struct nx842_devdata *old_devdata, *new_devdata = NULL;
1032        unsigned long flags;
1033        int ret = 0;
1034
1035        new_devdata = kzalloc(sizeof(*new_devdata), GFP_NOFS);
1036        if (!new_devdata)
1037                return -ENOMEM;
1038
1039        new_devdata->counters = kzalloc(sizeof(*new_devdata->counters),
1040                        GFP_NOFS);
1041        if (!new_devdata->counters) {
1042                kfree(new_devdata);
1043                return -ENOMEM;
1044        }
1045
1046        spin_lock_irqsave(&devdata_mutex, flags);
1047        old_devdata = rcu_dereference_check(devdata,
1048                        lockdep_is_held(&devdata_mutex));
1049
1050        if (old_devdata && old_devdata->vdev != NULL) {
1051                dev_err(&viodev->dev, "%s: Attempt to register more than one instance of the hardware\n", __func__);
1052                ret = -1;
1053                goto error_unlock;
1054        }
1055
1056        dev_set_drvdata(&viodev->dev, NULL);
1057
1058        new_devdata->vdev = viodev;
1059        new_devdata->dev = &viodev->dev;
1060        nx842_OF_set_defaults(new_devdata);
1061
1062        rcu_assign_pointer(devdata, new_devdata);
1063        spin_unlock_irqrestore(&devdata_mutex, flags);
1064        synchronize_rcu();
1065        kfree(old_devdata);
1066
1067        of_reconfig_notifier_register(&nx842_of_nb);
1068
1069        ret = nx842_OF_upd(NULL);
1070        if (ret)
1071                goto error;
1072
1073        ret = crypto_register_alg(&nx842_pseries_alg);
1074        if (ret) {
1075                dev_err(&viodev->dev, "could not register comp alg: %d\n", ret);
1076                goto error;
1077        }
1078
1079        rcu_read_lock();
1080        dev_set_drvdata(&viodev->dev, rcu_dereference(devdata));
1081        rcu_read_unlock();
1082
1083        if (sysfs_create_group(&viodev->dev.kobj, &nx842_attribute_group)) {
1084                dev_err(&viodev->dev, "could not create sysfs device attributes\n");
1085                ret = -1;
1086                goto error;
1087        }
1088
1089        if (caps_feat) {
1090                if (sysfs_create_group(&viodev->dev.kobj,
1091                                        &nxcop_caps_attr_group)) {
1092                        dev_err(&viodev->dev,
1093                                "Could not create sysfs NX capability entries\n");
1094                        ret = -1;
1095                        goto error;
1096                }
1097        }
1098
1099        return 0;
1100
1101error_unlock:
1102        spin_unlock_irqrestore(&devdata_mutex, flags);
1103        if (new_devdata)
1104                kfree(new_devdata->counters);
1105        kfree(new_devdata);
1106error:
1107        return ret;
1108}
1109
1110static void nx842_remove(struct vio_dev *viodev)
1111{
1112        struct nx842_devdata *old_devdata;
1113        unsigned long flags;
1114
1115        pr_info("Removing IBM Power 842 compression device\n");
1116        sysfs_remove_group(&viodev->dev.kobj, &nx842_attribute_group);
1117
1118        if (caps_feat)
1119                sysfs_remove_group(&viodev->dev.kobj, &nxcop_caps_attr_group);
1120
1121        crypto_unregister_alg(&nx842_pseries_alg);
1122
1123        spin_lock_irqsave(&devdata_mutex, flags);
1124        old_devdata = rcu_dereference_check(devdata,
1125                        lockdep_is_held(&devdata_mutex));
1126        of_reconfig_notifier_unregister(&nx842_of_nb);
1127        RCU_INIT_POINTER(devdata, NULL);
1128        spin_unlock_irqrestore(&devdata_mutex, flags);
1129        synchronize_rcu();
1130        dev_set_drvdata(&viodev->dev, NULL);
1131        if (old_devdata)
1132                kfree(old_devdata->counters);
1133        kfree(old_devdata);
1134}
1135
1136/*
1137 * Get NX capabilities from the hypervisor.
1138 * Only NXGZIP capabilities are provided by the hypersvisor right
1139 * now and these values are available to user space with sysfs.
1140 */
1141static void __init nxcop_get_capabilities(void)
1142{
1143        struct hv_vas_all_caps *hv_caps;
1144        struct hv_nx_cop_caps *hv_nxc;
1145        int rc;
1146
1147        hv_caps = kmalloc(sizeof(*hv_caps), GFP_KERNEL);
1148        if (!hv_caps)
1149                return;
1150        /*
1151         * Get NX overall capabilities with feature type=0
1152         */
1153        rc = h_query_vas_capabilities(H_QUERY_NX_CAPABILITIES, 0,
1154                                          (u64)virt_to_phys(hv_caps));
1155        if (rc)
1156                goto out;
1157
1158        caps_feat = be64_to_cpu(hv_caps->feat_type);
1159        /*
1160         * NX-GZIP feature available
1161         */
1162        if (caps_feat & VAS_NX_GZIP_FEAT_BIT) {
1163                hv_nxc = kmalloc(sizeof(*hv_nxc), GFP_KERNEL);
1164                if (!hv_nxc)
1165                        goto out;
1166                /*
1167                 * Get capabilities for NX-GZIP feature
1168                 */
1169                rc = h_query_vas_capabilities(H_QUERY_NX_CAPABILITIES,
1170                                                  VAS_NX_GZIP_FEAT,
1171                                                  (u64)virt_to_phys(hv_nxc));
1172        } else {
1173                pr_err("NX-GZIP feature is not available\n");
1174                rc = -EINVAL;
1175        }
1176
1177        if (!rc) {
1178                nx_cop_caps.descriptor = be64_to_cpu(hv_nxc->descriptor);
1179                nx_cop_caps.req_max_processed_len =
1180                                be64_to_cpu(hv_nxc->req_max_processed_len);
1181                nx_cop_caps.min_compress_len =
1182                                be64_to_cpu(hv_nxc->min_compress_len);
1183                nx_cop_caps.min_decompress_len =
1184                                be64_to_cpu(hv_nxc->min_decompress_len);
1185        } else {
1186                caps_feat = 0;
1187        }
1188
1189        kfree(hv_nxc);
1190out:
1191        kfree(hv_caps);
1192}
1193
1194static const struct vio_device_id nx842_vio_driver_ids[] = {
1195        {"ibm,compression-v1", "ibm,compression"},
1196        {"", ""},
1197};
1198MODULE_DEVICE_TABLE(vio, nx842_vio_driver_ids);
1199
1200static struct vio_driver nx842_vio_driver = {
1201        .name = KBUILD_MODNAME,
1202        .probe = nx842_probe,
1203        .remove = nx842_remove,
1204        .get_desired_dma = nx842_get_desired_dma,
1205        .id_table = nx842_vio_driver_ids,
1206};
1207
1208static int __init nx842_pseries_init(void)
1209{
1210        struct nx842_devdata *new_devdata;
1211        int ret;
1212
1213        if (!of_find_compatible_node(NULL, NULL, "ibm,compression"))
1214                return -ENODEV;
1215
1216        RCU_INIT_POINTER(devdata, NULL);
1217        new_devdata = kzalloc(sizeof(*new_devdata), GFP_KERNEL);
1218        if (!new_devdata)
1219                return -ENOMEM;
1220
1221        RCU_INIT_POINTER(devdata, new_devdata);
1222        /*
1223         * Get NX capabilities from the hypervisor.
1224         */
1225        nxcop_get_capabilities();
1226
1227        ret = vio_register_driver(&nx842_vio_driver);
1228        if (ret) {
1229                pr_err("Could not register VIO driver %d\n", ret);
1230
1231                kfree(new_devdata);
1232                return ret;
1233        }
1234
1235        ret = vas_register_api_pseries(THIS_MODULE, VAS_COP_TYPE_GZIP,
1236                                       "nx-gzip");
1237
1238        if (ret)
1239                pr_err("NX-GZIP is not supported. Returned=%d\n", ret);
1240
1241        return 0;
1242}
1243
1244module_init(nx842_pseries_init);
1245
1246static void __exit nx842_pseries_exit(void)
1247{
1248        struct nx842_devdata *old_devdata;
1249        unsigned long flags;
1250
1251        vas_unregister_api_pseries();
1252
1253        crypto_unregister_alg(&nx842_pseries_alg);
1254
1255        spin_lock_irqsave(&devdata_mutex, flags);
1256        old_devdata = rcu_dereference_check(devdata,
1257                        lockdep_is_held(&devdata_mutex));
1258        RCU_INIT_POINTER(devdata, NULL);
1259        spin_unlock_irqrestore(&devdata_mutex, flags);
1260        synchronize_rcu();
1261        if (old_devdata && old_devdata->dev)
1262                dev_set_drvdata(old_devdata->dev, NULL);
1263        kfree(old_devdata);
1264        vio_unregister_driver(&nx842_vio_driver);
1265}
1266
1267module_exit(nx842_pseries_exit);
1268
1269
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