drivers/net/ethernet/chelsio/libcxgb/libcxgb_ppm.c

   1 /*
   2  * libcxgb_ppm.c: Chelsio common library for T3/T4/T5 iSCSI PagePod Manager
   3  *
   4  * Copyright (c) 2016 Chelsio Communications, Inc. All rights reserved.
   5  *
   6  * This software is available to you under a choice of one of two
   7  * licenses.  You may choose to be licensed under the terms of the GNU
   8  * General Public License (GPL) Version 2, available from the file
   9  * COPYING in the main directory of this source tree, or the
  10  * OpenIB.org BSD license below:
  11  *
  12  *     Redistribution and use in source and binary forms, with or
  13  *     without modification, are permitted provided that the following
  14  *     conditions are met:
  15  *
  16  *      - Redistributions of source code must retain the above
  17  *        copyright notice, this list of conditions and the following
  18  *        disclaimer.
  19  *
  20  *      - Redistributions in binary form must reproduce the above
  21  *        copyright notice, this list of conditions and the following
  22  *        disclaimer in the documentation and/or other materials
  23  *        provided with the distribution.
  24  *
  25  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  26  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  27  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  28  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  29  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  30  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  31  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  32  * SOFTWARE.
  33  *
  34  * Written by: Karen Xie (kxie@chelsio.com)
  35  */
  36
  37 #define DRV_NAME "libcxgb"
  38 #define pr_fmt(fmt) DRV_NAME ": " fmt
  39
  40 #include <linux/kernel.h>
  41 #include <linux/module.h>
  42 #include <linux/errno.h>
  43 #include <linux/types.h>
  44 #include <linux/debugfs.h>
  45 #include <linux/export.h>
  46 #include <linux/list.h>
  47 #include <linux/skbuff.h>
  48 #include <linux/pci.h>
  49 #include <linux/scatterlist.h>
  50
  51 #include "libcxgb_ppm.h"
  52
  53 /* Direct Data Placement -
  54  * Directly place the iSCSI Data-In or Data-Out PDU's payload into
  55  * pre-posted final destination host-memory buffers based on the
  56  * Initiator Task Tag (ITT) in Data-In or Target Task Tag (TTT)
  57  * in Data-Out PDUs. The host memory address is programmed into
  58  * h/w in the format of pagepod entries. The location of the
  59  * pagepod entry is encoded into ddp tag which is used as the base
  60  * for ITT/TTT.
  61  */
  62
  63 /* Direct-Data Placement page size adjustment
  64  */
  65 int cxgbi_ppm_find_page_index(struct cxgbi_ppm *ppm, unsigned long pgsz)
  66 {
  67         struct cxgbi_tag_format *tformat = &ppm->tformat;
  68         int i;
  69
  70         for (i = 0; i < DDP_PGIDX_MAX; i++) {
  71                 if (pgsz == 1UL << (DDP_PGSZ_BASE_SHIFT +
  72                                          tformat->pgsz_order[i])) {
  73                         pr_debug("%s: %s ppm, pgsz %lu -> idx %d.\n",
  74                                  __func__, ppm->ndev->name, pgsz, i);
  75                         return i;
  76                 }
  77         }
  78         pr_info("ippm: ddp page size %lu not supported.\n", pgsz);
  79         return DDP_PGIDX_MAX;
  80 }
  81
  82 /* DDP setup & teardown
  83  */
  84 static int ppm_find_unused_entries(unsigned long *bmap,
  85                                    unsigned int max_ppods,
  86                                    unsigned int start,
  87                                    unsigned int nr,
  88                                    unsigned int align_mask)
  89 {
  90         unsigned long i;
  91
  92         i = bitmap_find_next_zero_area(bmap, max_ppods, start, nr, align_mask);
  93
  94         if (unlikely(i >= max_ppods) && (start > nr))
  95                 i = bitmap_find_next_zero_area(bmap, max_ppods, 0, start - 1,
  96                                                align_mask);
  97         if (unlikely(i >= max_ppods))
  98                 return -ENOSPC;
  99
 100         bitmap_set(bmap, i, nr);
 101         return (int)i;
 102 }
 103
 104 static void ppm_mark_entries(struct cxgbi_ppm *ppm, int i, int count,
 105                              unsigned long caller_data)
 106 {
 107         struct cxgbi_ppod_data *pdata = ppm->ppod_data + i;
 108
 109         pdata->caller_data = caller_data;
 110         pdata->npods = count;
 111
 112         if (pdata->color == ((1 << PPOD_IDX_SHIFT) - 1))
 113                 pdata->color = 0;
 114         else
 115                 pdata->color++;
 116 }
 117
 118 static int ppm_get_cpu_entries(struct cxgbi_ppm *ppm, unsigned int count,
 119                                unsigned long caller_data)
 120 {
 121         struct cxgbi_ppm_pool *pool;
 122         unsigned int cpu;
 123         int i;
 124
 125         if (!ppm->pool)
 126                 return -EINVAL;
 127
 128         cpu = get_cpu();
 129         pool = per_cpu_ptr(ppm->pool, cpu);
 130         spin_lock_bh(&pool->lock);
 131         put_cpu();
 132
 133         i = ppm_find_unused_entries(pool->bmap, ppm->pool_index_max,
 134                                     pool->next, count, 0);
 135         if (i < 0) {
 136                 pool->next = 0;
 137                 spin_unlock_bh(&pool->lock);
 138                 return -ENOSPC;
 139         }
 140
 141         pool->next = i + count;
 142         if (pool->next >= ppm->pool_index_max)
 143                 pool->next = 0;
 144
 145         spin_unlock_bh(&pool->lock);
 146
 147         pr_debug("%s: cpu %u, idx %d + %d (%d), next %u.\n",
 148                  __func__, cpu, i, count, i + cpu * ppm->pool_index_max,
 149                 pool->next);
 150
 151         i += cpu * ppm->pool_index_max;
 152         ppm_mark_entries(ppm, i, count, caller_data);
 153
 154         return i;
 155 }
 156
 157 static int ppm_get_entries(struct cxgbi_ppm *ppm, unsigned int count,
 158                            unsigned long caller_data)
 159 {
 160         int i;
 161
 162         spin_lock_bh(&ppm->map_lock);
 163         i = ppm_find_unused_entries(ppm->ppod_bmap, ppm->bmap_index_max,
 164                                     ppm->next, count, 0);
 165         if (i < 0) {
 166                 ppm->next = 0;
 167                 spin_unlock_bh(&ppm->map_lock);
 168                 pr_debug("ippm: NO suitable entries %u available.\n",
 169                          count);
 170                 return -ENOSPC;
 171         }
 172
 173         ppm->next = i + count;
 174         if (ppm->max_index_in_edram && (ppm->next >= ppm->max_index_in_edram))
 175                 ppm->next = 0;
 176         else if (ppm->next >= ppm->bmap_index_max)
 177                 ppm->next = 0;
 178
 179         spin_unlock_bh(&ppm->map_lock);
 180
 181         pr_debug("%s: idx %d + %d (%d), next %u, caller_data 0x%lx.\n",
 182                  __func__, i, count, i + ppm->pool_rsvd, ppm->next,
 183                  caller_data);
 184
 185         i += ppm->pool_rsvd;
 186         ppm_mark_entries(ppm, i, count, caller_data);
 187
 188         return i;
 189 }
 190
 191 static void ppm_unmark_entries(struct cxgbi_ppm *ppm, int i, int count)
 192 {
 193         pr_debug("%s: idx %d + %d.\n", __func__, i, count);
 194
 195         if (i < ppm->pool_rsvd) {
 196                 unsigned int cpu;
 197                 struct cxgbi_ppm_pool *pool;
 198
 199                 cpu = i / ppm->pool_index_max;
 200                 i %= ppm->pool_index_max;
 201
 202                 pool = per_cpu_ptr(ppm->pool, cpu);
 203                 spin_lock_bh(&pool->lock);
 204                 bitmap_clear(pool->bmap, i, count);
 205
 206                 if (i < pool->next)
 207                         pool->next = i;
 208                 spin_unlock_bh(&pool->lock);
 209
 210                 pr_debug("%s: cpu %u, idx %d, next %u.\n",
 211                          __func__, cpu, i, pool->next);
 212         } else {
 213                 spin_lock_bh(&ppm->map_lock);
 214
 215                 i -= ppm->pool_rsvd;
 216                 bitmap_clear(ppm->ppod_bmap, i, count);
 217
 218                 if (i < ppm->next)
 219                         ppm->next = i;
 220                 spin_unlock_bh(&ppm->map_lock);
 221
 222                 pr_debug("%s: idx %d, next %u.\n", __func__, i, ppm->next);
 223         }
 224 }
 225
 226 void cxgbi_ppm_ppod_release(struct cxgbi_ppm *ppm, u32 idx)
 227 {
 228         struct cxgbi_ppod_data *pdata;
 229
 230         if (idx >= ppm->ppmax) {
 231                 pr_warn("ippm: idx too big %u > %u.\n", idx, ppm->ppmax);
 232                 return;
 233         }
 234
 235         pdata = ppm->ppod_data + idx;
 236         if (!pdata->npods) {
 237                 pr_warn("ippm: idx %u, npods 0.\n", idx);
 238                 return;
 239         }
 240
 241         pr_debug("release idx %u, npods %u.\n", idx, pdata->npods);
 242         ppm_unmark_entries(ppm, idx, pdata->npods);
 243 }
 244 EXPORT_SYMBOL(cxgbi_ppm_ppod_release);
 245
 246 int cxgbi_ppm_ppods_reserve(struct cxgbi_ppm *ppm, unsigned short nr_pages,
 247                             u32 per_tag_pg_idx, u32 *ppod_idx,
 248                             u32 *ddp_tag, unsigned long caller_data)
 249 {
 250         struct cxgbi_ppod_data *pdata;
 251         unsigned int npods;
 252         int idx = -1;
 253         unsigned int hwidx;
 254         u32 tag;
 255
 256         npods = (nr_pages + PPOD_PAGES_MAX - 1) >> PPOD_PAGES_SHIFT;
 257         if (!npods) {
 258                 pr_warn("%s: pages %u -> npods %u, full.\n",
 259                         __func__, nr_pages, npods);
 260                 return -EINVAL;
 261         }
 262
 263         /* grab from cpu pool first */
 264         idx = ppm_get_cpu_entries(ppm, npods, caller_data);
 265         /* try the general pool */
 266         if (idx < 0)
 267                 idx = ppm_get_entries(ppm, npods, caller_data);
 268         if (idx < 0) {
 269                 pr_debug("ippm: pages %u, nospc %u, nxt %u, 0x%lx.\n",
 270                          nr_pages, npods, ppm->next, caller_data);
 271                 return idx;
 272         }
 273
 274         pdata = ppm->ppod_data + idx;
 275         hwidx = ppm->base_idx + idx;
 276
 277         tag = cxgbi_ppm_make_ddp_tag(hwidx, pdata->color);
 278
 279         if (per_tag_pg_idx)
 280                 tag |= (per_tag_pg_idx << 30) & 0xC0000000;
 281
 282         *ppod_idx = idx;
 283         *ddp_tag = tag;
 284
 285         pr_debug("ippm: sg %u, tag 0x%x(%u,%u), data 0x%lx.\n",
 286                  nr_pages, tag, idx, npods, caller_data);
 287
 288         return npods;
 289 }
 290 EXPORT_SYMBOL(cxgbi_ppm_ppods_reserve);
 291
 292 void cxgbi_ppm_make_ppod_hdr(struct cxgbi_ppm *ppm, u32 tag,
 293                              unsigned int tid, unsigned int offset,
 294                              unsigned int length,
 295                              struct cxgbi_pagepod_hdr *hdr)
 296 {
 297         /* The ddp tag in pagepod should be with bit 31:30 set to 0.
 298          * The ddp Tag on the wire should be with non-zero 31:30 to the peer
 299          */
 300         tag &= 0x3FFFFFFF;
 301
 302         hdr->vld_tid = htonl(PPOD_VALID_FLAG | PPOD_TID(tid));
 303
 304         hdr->rsvd = 0;
 305         hdr->pgsz_tag_clr = htonl(tag & ppm->tformat.idx_clr_mask);
 306         hdr->max_offset = htonl(length);
 307         hdr->page_offset = htonl(offset);
 308
 309         pr_debug("ippm: tag 0x%x, tid 0x%x, xfer %u, off %u.\n",
 310                  tag, tid, length, offset);
 311 }
 312 EXPORT_SYMBOL(cxgbi_ppm_make_ppod_hdr);
 313
 314 static void ppm_free(struct cxgbi_ppm *ppm)
 315 {
 316         vfree(ppm);
 317 }
 318
 319 static void ppm_destroy(struct kref *kref)
 320 {
 321         struct cxgbi_ppm *ppm = container_of(kref,
 322                                              struct cxgbi_ppm,
 323                                              refcnt);
 324         pr_info("ippm: kref 0, destroy %s ppm 0x%p.\n",
 325                 ppm->ndev->name, ppm);
 326
 327         *ppm->ppm_pp = NULL;
 328
 329         free_percpu(ppm->pool);
 330         ppm_free(ppm);
 331 }
 332
 333 int cxgbi_ppm_release(struct cxgbi_ppm *ppm)
 334 {
 335         if (ppm) {
 336                 int rv;
 337
 338                 rv = kref_put(&ppm->refcnt, ppm_destroy);
 339                 return rv;
 340         }
 341         return 1;
 342 }
 343 EXPORT_SYMBOL(cxgbi_ppm_release);
 344
 345 static struct cxgbi_ppm_pool *ppm_alloc_cpu_pool(unsigned int *total,
 346                                                  unsigned int *pcpu_ppmax)
 347 {
 348         struct cxgbi_ppm_pool *pools;
 349         unsigned int ppmax = (*total) / num_possible_cpus();
 350         unsigned int max = (PCPU_MIN_UNIT_SIZE - sizeof(*pools)) << 3;
 351         unsigned int bmap;
 352         unsigned int alloc_sz;
 353         unsigned int count = 0;
 354         unsigned int cpu;
 355
 356         /* make sure per cpu pool fits into PCPU_MIN_UNIT_SIZE */
 357         if (ppmax > max)
 358                 ppmax = max;
 359
 360         /* pool size must be multiple of unsigned long */
 361         bmap = ppmax / BITS_PER_TYPE(unsigned long);
 362         if (!bmap)
 363                 return NULL;
 364
 365         ppmax = (bmap * sizeof(unsigned long)) << 3;
 366
 367         alloc_sz = sizeof(*pools) + sizeof(unsigned long) * bmap;
 368         pools = __alloc_percpu(alloc_sz, __alignof__(struct cxgbi_ppm_pool));
 369
 370         if (!pools)
 371                 return NULL;
 372
 373         for_each_possible_cpu(cpu) {
 374                 struct cxgbi_ppm_pool *ppool = per_cpu_ptr(pools, cpu);
 375
 376                 memset(ppool, 0, alloc_sz);
 377                 spin_lock_init(&ppool->lock);
 378                 count += ppmax;
 379         }
 380
 381         *total = count;
 382         *pcpu_ppmax = ppmax;
 383
 384         return pools;
 385 }
 386
 387 int cxgbi_ppm_init(void **ppm_pp, struct net_device *ndev,
 388                    struct pci_dev *pdev, void *lldev,
 389                    struct cxgbi_tag_format *tformat, unsigned int iscsi_size,
 390                    unsigned int llimit, unsigned int start,
 391                    unsigned int reserve_factor, unsigned int iscsi_edram_start,
 392                    unsigned int iscsi_edram_size)
 393 {
 394         struct cxgbi_ppm *ppm = (struct cxgbi_ppm *)(*ppm_pp);
 395         struct cxgbi_ppm_pool *pool = NULL;
 396         unsigned int pool_index_max = 0;
 397         unsigned int ppmax_pool = 0;
 398         unsigned int ppod_bmap_size;
 399         unsigned int alloc_sz;
 400         unsigned int ppmax;
 401
 402         if (!iscsi_edram_start)
 403                 iscsi_edram_size = 0;
 404
 405         if (iscsi_edram_size &&
 406             ((iscsi_edram_start + iscsi_edram_size) != start)) {
 407                 pr_err("iscsi ppod region not contiguous: EDRAM start 0x%x "
 408                         "size 0x%x DDR start 0x%x\n",
 409                         iscsi_edram_start, iscsi_edram_size, start);
 410                 return -EINVAL;
 411         }
 412
 413         if (iscsi_edram_size) {
 414                 reserve_factor = 0;
 415                 start = iscsi_edram_start;
 416         }
 417
 418         ppmax = (iscsi_edram_size + iscsi_size) >> PPOD_SIZE_SHIFT;
 419
 420         if (ppm) {
 421                 pr_info("ippm: %s, ppm 0x%p,0x%p already initialized, %u/%u.\n",
 422                         ndev->name, ppm_pp, ppm, ppm->ppmax, ppmax);
 423                 kref_get(&ppm->refcnt);
 424                 return 1;
 425         }
 426
 427         if (reserve_factor) {
 428                 ppmax_pool = ppmax / reserve_factor;
 429                 pool = ppm_alloc_cpu_pool(&ppmax_pool, &pool_index_max);
 430                 if (!pool) {
 431                         ppmax_pool = 0;
 432                         reserve_factor = 0;
 433                 }
 434
 435                 pr_debug("%s: ppmax %u, cpu total %u, per cpu %u.\n",
 436                          ndev->name, ppmax, ppmax_pool, pool_index_max);
 437         }
 438
 439         ppod_bmap_size = BITS_TO_LONGS(ppmax - ppmax_pool);
 440         alloc_sz = sizeof(struct cxgbi_ppm) +
 441                         ppmax * (sizeof(struct cxgbi_ppod_data)) +
 442                         ppod_bmap_size * sizeof(unsigned long);
 443
 444         ppm = vzalloc(alloc_sz);
 445         if (!ppm)
 446                 goto release_ppm_pool;
 447
 448         ppm->ppod_bmap = (unsigned long *)(&ppm->ppod_data[ppmax]);
 449
 450         if ((ppod_bmap_size >> 3) > (ppmax - ppmax_pool)) {
 451                 unsigned int start = ppmax - ppmax_pool;
 452                 unsigned int end = ppod_bmap_size >> 3;
 453
 454                 bitmap_set(ppm->ppod_bmap, ppmax, end - start);
 455                 pr_info("%s: %u - %u < %u * 8, mask extra bits %u, %u.\n",
 456                         __func__, ppmax, ppmax_pool, ppod_bmap_size, start,
 457                         end);
 458         }
 459         if (iscsi_edram_size) {
 460                 unsigned int first_ddr_idx =
 461                                 iscsi_edram_size >> PPOD_SIZE_SHIFT;
 462
 463                 ppm->max_index_in_edram = first_ddr_idx - 1;
 464                 bitmap_set(ppm->ppod_bmap, first_ddr_idx, 1);
 465                 pr_debug("reserved %u ppod in bitmap\n", first_ddr_idx);
 466         }
 467
 468         spin_lock_init(&ppm->map_lock);
 469         kref_init(&ppm->refcnt);
 470
 471         memcpy(&ppm->tformat, tformat, sizeof(struct cxgbi_tag_format));
 472
 473         ppm->ppm_pp = ppm_pp;
 474         ppm->ndev = ndev;
 475         ppm->pdev = pdev;
 476         ppm->lldev = lldev;
 477         ppm->ppmax = ppmax;
 478         ppm->next = 0;
 479         ppm->llimit = llimit;
 480         ppm->base_idx = start > llimit ?
 481                         (start - llimit + 1) >> PPOD_SIZE_SHIFT : 0;
 482         ppm->bmap_index_max = ppmax - ppmax_pool;
 483
 484         ppm->pool = pool;
 485         ppm->pool_rsvd = ppmax_pool;
 486         ppm->pool_index_max = pool_index_max;
 487
 488         /* check one more time */
 489         if (*ppm_pp) {
 490                 ppm_free(ppm);
 491                 ppm = (struct cxgbi_ppm *)(*ppm_pp);
 492
 493                 pr_info("ippm: %s, ppm 0x%p,0x%p already initialized, %u/%u.\n",
 494                         ndev->name, ppm_pp, *ppm_pp, ppm->ppmax, ppmax);
 495
 496                 kref_get(&ppm->refcnt);
 497                 return 1;
 498         }
 499         *ppm_pp = ppm;
 500
 501         ppm->tformat.pgsz_idx_dflt = cxgbi_ppm_find_page_index(ppm, PAGE_SIZE);
 502
 503         pr_info("ippm %s: ppm 0x%p, 0x%p, base %u/%u, pg %lu,%u, rsvd %u,%u.\n",
 504                 ndev->name, ppm_pp, ppm, ppm->base_idx, ppm->ppmax, PAGE_SIZE,
 505                 ppm->tformat.pgsz_idx_dflt, ppm->pool_rsvd,
 506                 ppm->pool_index_max);
 507
 508         return 0;
 509
 510 release_ppm_pool:
 511         free_percpu(pool);
 512         return -ENOMEM;
 513 }
 514 EXPORT_SYMBOL(cxgbi_ppm_init);
 515
 516 unsigned int cxgbi_tagmask_set(unsigned int ppmax)
 517 {
 518         unsigned int bits = fls(ppmax);
 519
 520         if (bits > PPOD_IDX_MAX_SIZE)
 521                 bits = PPOD_IDX_MAX_SIZE;
 522
 523         pr_info("ippm: ppmax %u/0x%x -> bits %u, tagmask 0x%x.\n",
 524                 ppmax, ppmax, bits, 1 << (bits + PPOD_IDX_SHIFT));
 525
 526         return 1 << (bits + PPOD_IDX_SHIFT);
 527 }
 528 EXPORT_SYMBOL(cxgbi_tagmask_set);
 529
 530 MODULE_AUTHOR("Chelsio Communications");
 531 MODULE_DESCRIPTION("Chelsio common library");
 532 MODULE_LICENSE("Dual BSD/GPL");