drivers/scsi/sd_dif.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  * sd_dif.c - SCSI Data Integrity Field
0004  *
0005  * Copyright (C) 2007, 2008 Oracle Corporation
0006  * Written by: Martin K. Petersen <martin.petersen@oracle.com>
0007  */
0008
0009 #include <linux/blk-integrity.h>
0010 #include <linux/t10-pi.h>
0011
0012 #include <scsi/scsi.h>
0013 #include <scsi/scsi_cmnd.h>
0014 #include <scsi/scsi_dbg.h>
0015 #include <scsi/scsi_device.h>
0016 #include <scsi/scsi_driver.h>
0017 #include <scsi/scsi_eh.h>
0018 #include <scsi/scsi_host.h>
0019 #include <scsi/scsi_ioctl.h>
0020 #include <scsi/scsicam.h>
0021
0022 #include "sd.h"
0023
0024 /*
0025  * Configure exchange of protection information between OS and HBA.
0026  */
0027 void sd_dif_config_host(struct scsi_disk *sdkp)
0028 {
0029     struct scsi_device *sdp = sdkp->device;
0030     struct gendisk *disk = sdkp->disk;
0031     u8 type = sdkp->protection_type;
0032     struct blk_integrity bi;
0033     int dif, dix;
0034
0035     dif = scsi_host_dif_capable(sdp->host, type);
0036     dix = scsi_host_dix_capable(sdp->host, type);
0037
0038     if (!dix && scsi_host_dix_capable(sdp->host, 0)) {
0039         dif = 0; dix = 1;
0040     }
0041
0042     if (!dix)
0043         return;
0044
0045     memset(&bi, 0, sizeof(bi));
0046
0047     /* Enable DMA of protection information */
0048     if (scsi_host_get_guard(sdkp->device->host) & SHOST_DIX_GUARD_IP) {
0049         if (type == T10_PI_TYPE3_PROTECTION)
0050             bi.profile = &t10_pi_type3_ip;
0051         else
0052             bi.profile = &t10_pi_type1_ip;
0053
0054         bi.flags |= BLK_INTEGRITY_IP_CHECKSUM;
0055     } else
0056         if (type == T10_PI_TYPE3_PROTECTION)
0057             bi.profile = &t10_pi_type3_crc;
0058         else
0059             bi.profile = &t10_pi_type1_crc;
0060
0061     bi.tuple_size = sizeof(struct t10_pi_tuple);
0062
0063     if (dif && type) {
0064         bi.flags |= BLK_INTEGRITY_DEVICE_CAPABLE;
0065
0066         if (!sdkp->ATO)
0067             goto out;
0068
0069         if (type == T10_PI_TYPE3_PROTECTION)
0070             bi.tag_size = sizeof(u16) + sizeof(u32);
0071         else
0072             bi.tag_size = sizeof(u16);
0073     }
0074
0075     sd_printk(KERN_NOTICE, sdkp,
0076           "Enabling DIX %s, application tag size %u bytes\n",
0077           bi.profile->name, bi.tag_size);
0078 out:
0079     blk_integrity_register(disk, &bi);
0080 }
0081