lustre/osd-ldiskfs/osd_integrity.c

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; If not, see
  18  * http://www.gnu.org/licenses/gpl-2.0.html
  19  *
  20  * GPL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 2018, DataDirect Networks Storage.
  24  * Author: Li Xi.
  25  *
  26  * Data integrity functions for OSD
  27  * Codes copied from kernel 3.10.0-862.el7
  28  * drivers/scsi/sd_dif.c and block/t10-pi.c
  29  */
  30 #ifdef HAVE_LINUX_BLK_INTEGRITY_HEADER
  31  #include <linux/blk-integrity.h>
  32 #else
  33  #include <linux/blkdev.h>
  34 #endif
  35 #include <linux/blk_types.h>
  36
  37 #include <obd_cksum.h>
  38 #include <lustre_compat.h>
  39
  40 #include "osd_internal.h"
  41
  42 #if IS_ENABLED(CONFIG_CRC_T10DIF)
  43 #ifdef HAVE_BLK_INTEGRITY_ITER
  44 # define blk_status_gen blk_status_t
  45 # define RETURN_GEN(_gen_fn) return _gen_fn
  46 #else
  47 # define blk_status_gen void
  48 # define RETURN_GEN(_gen_fn) _gen_fn
  49 # define blk_integrity_iter blk_integrity_exchg
  50 # define interval sector_size
  51 # define seed sector
  52 # define blk_status_t int
  53 # define BLK_STS_PROTECTION -EIO
  54 # define BLK_STS_OK 0
  55 #endif
  56 /*
  57  * Data Integrity Field tuple.
  58  */
  59 struct t10_pi_tuple {
  60        __be16 guard_tag;        /* Checksum */
  61        __be16 app_tag;          /* Opaque storage */
  62        __be32 ref_tag;          /* Target LBA or indirect LBA */
  63 };
  64
  65 #define T10_PI_APP_ESCAPE cpu_to_be16(0xffff)
  66 #define T10_PI_REF_ESCAPE cpu_to_be32(0xffffffff)
  67
  68 static struct niobuf_local *find_lnb(struct blk_integrity_iter *iter)
  69 {
  70         struct bio *bio = iter->bio;
  71         struct bio_vec *bv = &bio->bi_io_vec[iter->bi_idx];
  72         struct osd_bio_private *bio_private = bio->bi_private;
  73         struct osd_iobuf *iobuf = bio_private->obp_iobuf;
  74         int index = bio_private->obp_start_page_idx + iter->bi_idx;
  75         int i;
  76
  77         /*
  78          * blocks are contiguous in bio but pages added to bio
  79          * could have a gap comparing to iobuf->dr_pages.
  80          * e.g. a page mapped to a hole in the middle.
  81          */
  82         for (i = index; i < iobuf->dr_npages; i++) {
  83                 if (iobuf->dr_pages[i] == bv->bv_page)
  84                         return iobuf->dr_lnbs[i];
  85         }
  86
  87         return NULL;
  88 }
  89
  90 /*
  91  * Type 1 and Type 2 protection use the same format: 16 bit guard tag,
  92  * 16 bit app tag, 32 bit reference tag (sector number).
  93  *
  94  * Type 3 protection has a 16-bit guard tag and 16 + 32 bits of opaque
  95  * tag space.
  96  */
  97 static blk_status_gen osd_dif_generate(struct blk_integrity_iter *iter,
  98                                 obd_dif_csum_fn *fn, enum osd_t10_type type)
  99 {
 100         struct niobuf_local *lnb = find_lnb(iter);
 101         __be16 *guard_buf = lnb ? lnb->lnb_guards : NULL;
 102         unsigned int i;
 103
 104         ENTRY;
 105         for (i = 0 ; i < iter->data_size ; i += iter->interval) {
 106                 struct t10_pi_tuple *pi = iter->prot_buf;
 107
 108                 if (lnb && lnb->lnb_guard_rpc) {
 109                         pi->guard_tag = *guard_buf;
 110                         guard_buf++;
 111                 } else {
 112                         pi->guard_tag = fn(iter->data_buf, iter->interval);
 113                 }
 114                 pi->app_tag = 0;
 115
 116                 if (type == OSD_T10_TYPE1)
 117                         pi->ref_tag = cpu_to_be32(lower_32_bits(iter->seed));
 118                 else /* if (type == OSD_T10_TYPE3) */
 119                         pi->ref_tag = 0;
 120
 121                 iter->data_buf += iter->interval;
 122                 iter->prot_buf += sizeof(struct t10_pi_tuple);
 123                 iter->seed++;
 124         }
 125
 126 #ifdef HAVE_BLK_INTEGRITY_ITER
 127         RETURN(BLK_STS_OK);
 128 #else
 129         RETURN_EXIT;
 130 #endif
 131 }
 132
 133 static blk_status_t osd_dif_verify(struct blk_integrity_iter *iter,
 134                                    obd_dif_csum_fn *fn, enum osd_t10_type type)
 135 {
 136         struct niobuf_local *lnb = find_lnb(iter);
 137         __be16 *guard_buf = lnb ? lnb->lnb_guards : NULL;
 138         unsigned int i;
 139
 140         ENTRY;
 141         for (i = 0 ; i < iter->data_size ; i += iter->interval) {
 142                 struct t10_pi_tuple *pi = iter->prot_buf;
 143                 __be16 csum;
 144
 145                 if (type == OSD_T10_TYPE1 ||
 146                     type == OSD_T10_TYPE2) {
 147                         if (pi->app_tag == T10_PI_APP_ESCAPE) {
 148                                 lnb = NULL;
 149                                 goto next;
 150                         }
 151
 152                         if (be32_to_cpu(pi->ref_tag) !=
 153                             lower_32_bits(iter->seed)) {
 154                                 CERROR("%s: ref tag error at location %llu (rcvd %u): rc = %d\n",
 155                                        iter->disk_name,
 156                                        (unsigned long long)iter->seed,
 157                                        be32_to_cpu(pi->ref_tag),
 158                                        BLK_STS_PROTECTION);
 159                                 RETURN(BLK_STS_PROTECTION);
 160                         }
 161                 } else  if (type == OSD_T10_TYPE3) {
 162                         if (pi->app_tag == T10_PI_APP_ESCAPE &&
 163                             pi->ref_tag == T10_PI_REF_ESCAPE) {
 164                                 lnb = NULL;
 165                                 goto next;
 166                         }
 167                 }
 168
 169                 csum = fn(iter->data_buf, iter->interval);
 170
 171                 if (pi->guard_tag != csum) {
 172                         CERROR("%s: guard tag error on sector %llu (rcvd %04x, want %04x): rc = %d\n",
 173                                iter->disk_name, (unsigned long long)iter->seed,
 174                                be16_to_cpu(pi->guard_tag), be16_to_cpu(csum),
 175                                BLK_STS_PROTECTION);
 176                         RETURN(BLK_STS_PROTECTION);
 177                 }
 178
 179                 if (guard_buf) {
 180                         *guard_buf = csum;
 181                         guard_buf++;
 182                 }
 183
 184 next:
 185                 iter->data_buf += iter->interval;
 186                 iter->prot_buf += sizeof(struct t10_pi_tuple);
 187                 iter->seed++;
 188         }
 189
 190         if (lnb)
 191                 lnb->lnb_guard_disk = 1;
 192
 193         RETURN(BLK_STS_OK);
 194 }
 195
 196 static blk_status_gen osd_dif_type1_generate_crc(struct blk_integrity_iter *iter)
 197 {
 198         RETURN_GEN(osd_dif_generate(iter, obd_dif_crc_fn, OSD_T10_TYPE1));
 199 }
 200
 201 static blk_status_gen osd_dif_type1_generate_ip(struct blk_integrity_iter *iter)
 202 {
 203         RETURN_GEN(osd_dif_generate(iter, obd_dif_ip_fn, OSD_T10_TYPE1));
 204 }
 205
 206 static blk_status_gen osd_dif_type3_generate_crc(struct blk_integrity_iter *iter)
 207 {
 208         RETURN_GEN(osd_dif_generate(iter, obd_dif_crc_fn, OSD_T10_TYPE3));
 209 }
 210
 211 static blk_status_gen osd_dif_type3_generate_ip(struct blk_integrity_iter *iter)
 212 {
 213         RETURN_GEN(osd_dif_generate(iter, obd_dif_ip_fn, OSD_T10_TYPE3));
 214 }
 215 static blk_status_t osd_dif_type1_verify_crc(struct blk_integrity_iter *iter)
 216 {
 217         return osd_dif_verify(iter, obd_dif_crc_fn, OSD_T10_TYPE1);
 218 }
 219
 220 static blk_status_t osd_dif_type1_verify_ip(struct blk_integrity_iter *iter)
 221 {
 222         return osd_dif_verify(iter, obd_dif_ip_fn, OSD_T10_TYPE1);
 223 }
 224
 225 static blk_status_t osd_dif_type3_verify_crc(struct blk_integrity_iter *iter)
 226 {
 227         return osd_dif_verify(iter, obd_dif_crc_fn, OSD_T10_TYPE3);
 228 }
 229
 230 static blk_status_t osd_dif_type3_verify_ip(struct blk_integrity_iter *iter)
 231 {
 232         return osd_dif_verify(iter, obd_dif_ip_fn, OSD_T10_TYPE3);
 233 }
 234
 235 int osd_get_integrity_profile(struct osd_device *osd,
 236                               integrity_gen_fn **generate_fn,
 237                               integrity_vrfy_fn **verify_fn)
 238 {
 239         switch (osd->od_t10_type) {
 240         case OSD_T10_TYPE1_CRC:
 241                 *verify_fn = osd_dif_type1_verify_crc;
 242                 *generate_fn = osd_dif_type1_generate_crc;
 243                 break;
 244         case OSD_T10_TYPE3_CRC:
 245                 *verify_fn = osd_dif_type3_verify_crc;
 246                 *generate_fn = osd_dif_type3_generate_crc;
 247                 break;
 248         case OSD_T10_TYPE1_IP:
 249                 *verify_fn = osd_dif_type1_verify_ip;
 250                 *generate_fn = osd_dif_type1_generate_ip;
 251                 break;
 252         case OSD_T10_TYPE3_IP:
 253                 *verify_fn = osd_dif_type3_verify_ip;
 254                 *generate_fn = osd_dif_type3_generate_ip;
 255                 break;
 256         default:
 257                 return -ENOTSUPP;
 258         }
 259
 260         return 0;
 261 }
 262 #endif /* CONFIG_CRC_T10DIF */