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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/drivers/scsi/sd_dif.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/drivers/scsi/sd_dif.c')
-rw-r--r--kernel/drivers/scsi/sd_dif.c205
1 files changed, 205 insertions, 0 deletions
diff --git a/kernel/drivers/scsi/sd_dif.c b/kernel/drivers/scsi/sd_dif.c
new file mode 100644
index 000000000..5c06d292b
--- /dev/null
+++ b/kernel/drivers/scsi/sd_dif.c
@@ -0,0 +1,205 @@
+/*
+ * sd_dif.c - SCSI Data Integrity Field
+ *
+ * Copyright (C) 2007, 2008 Oracle Corporation
+ * Written by: Martin K. Petersen <martin.petersen@oracle.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING. If not, write to
+ * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
+ * USA.
+ *
+ */
+
+#include <linux/blkdev.h>
+#include <linux/t10-pi.h>
+
+#include <scsi/scsi.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_dbg.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_driver.h>
+#include <scsi/scsi_eh.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_ioctl.h>
+#include <scsi/scsicam.h>
+
+#include "sd.h"
+
+/*
+ * Configure exchange of protection information between OS and HBA.
+ */
+void sd_dif_config_host(struct scsi_disk *sdkp)
+{
+ struct scsi_device *sdp = sdkp->device;
+ struct gendisk *disk = sdkp->disk;
+ u8 type = sdkp->protection_type;
+ int dif, dix;
+
+ dif = scsi_host_dif_capable(sdp->host, type);
+ dix = scsi_host_dix_capable(sdp->host, type);
+
+ if (!dix && scsi_host_dix_capable(sdp->host, 0)) {
+ dif = 0; dix = 1;
+ }
+
+ if (!dix)
+ return;
+
+ /* Enable DMA of protection information */
+ if (scsi_host_get_guard(sdkp->device->host) & SHOST_DIX_GUARD_IP) {
+ if (type == SD_DIF_TYPE3_PROTECTION)
+ blk_integrity_register(disk, &t10_pi_type3_ip);
+ else
+ blk_integrity_register(disk, &t10_pi_type1_ip);
+
+ disk->integrity->flags |= BLK_INTEGRITY_IP_CHECKSUM;
+ } else
+ if (type == SD_DIF_TYPE3_PROTECTION)
+ blk_integrity_register(disk, &t10_pi_type3_crc);
+ else
+ blk_integrity_register(disk, &t10_pi_type1_crc);
+
+ sd_printk(KERN_NOTICE, sdkp,
+ "Enabling DIX %s protection\n", disk->integrity->name);
+
+ /* Signal to block layer that we support sector tagging */
+ if (dif && type) {
+
+ disk->integrity->flags |= BLK_INTEGRITY_DEVICE_CAPABLE;
+
+ if (!sdkp->ATO)
+ return;
+
+ if (type == SD_DIF_TYPE3_PROTECTION)
+ disk->integrity->tag_size = sizeof(u16) + sizeof(u32);
+ else
+ disk->integrity->tag_size = sizeof(u16);
+
+ sd_printk(KERN_NOTICE, sdkp, "DIF application tag size %u\n",
+ disk->integrity->tag_size);
+ }
+}
+
+/*
+ * The virtual start sector is the one that was originally submitted
+ * by the block layer. Due to partitioning, MD/DM cloning, etc. the
+ * actual physical start sector is likely to be different. Remap
+ * protection information to match the physical LBA.
+ *
+ * From a protocol perspective there's a slight difference between
+ * Type 1 and 2. The latter uses 32-byte CDBs exclusively, and the
+ * reference tag is seeded in the CDB. This gives us the potential to
+ * avoid virt->phys remapping during write. However, at read time we
+ * don't know whether the virt sector is the same as when we wrote it
+ * (we could be reading from real disk as opposed to MD/DM device. So
+ * we always remap Type 2 making it identical to Type 1.
+ *
+ * Type 3 does not have a reference tag so no remapping is required.
+ */
+void sd_dif_prepare(struct scsi_cmnd *scmd)
+{
+ const int tuple_sz = sizeof(struct t10_pi_tuple);
+ struct bio *bio;
+ struct scsi_disk *sdkp;
+ struct t10_pi_tuple *pi;
+ u32 phys, virt;
+
+ sdkp = scsi_disk(scmd->request->rq_disk);
+
+ if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION)
+ return;
+
+ phys = scsi_prot_ref_tag(scmd);
+
+ __rq_for_each_bio(bio, scmd->request) {
+ struct bio_integrity_payload *bip = bio_integrity(bio);
+ struct bio_vec iv;
+ struct bvec_iter iter;
+ unsigned int j;
+
+ /* Already remapped? */
+ if (bip->bip_flags & BIP_MAPPED_INTEGRITY)
+ break;
+
+ virt = bip_get_seed(bip) & 0xffffffff;
+
+ bip_for_each_vec(iv, bip, iter) {
+ pi = kmap_atomic(iv.bv_page) + iv.bv_offset;
+
+ for (j = 0; j < iv.bv_len; j += tuple_sz, pi++) {
+
+ if (be32_to_cpu(pi->ref_tag) == virt)
+ pi->ref_tag = cpu_to_be32(phys);
+
+ virt++;
+ phys++;
+ }
+
+ kunmap_atomic(pi);
+ }
+
+ bip->bip_flags |= BIP_MAPPED_INTEGRITY;
+ }
+}
+
+/*
+ * Remap physical sector values in the reference tag to the virtual
+ * values expected by the block layer.
+ */
+void sd_dif_complete(struct scsi_cmnd *scmd, unsigned int good_bytes)
+{
+ const int tuple_sz = sizeof(struct t10_pi_tuple);
+ struct scsi_disk *sdkp;
+ struct bio *bio;
+ struct t10_pi_tuple *pi;
+ unsigned int j, intervals;
+ u32 phys, virt;
+
+ sdkp = scsi_disk(scmd->request->rq_disk);
+
+ if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION || good_bytes == 0)
+ return;
+
+ intervals = good_bytes / scsi_prot_interval(scmd);
+ phys = scsi_prot_ref_tag(scmd);
+
+ __rq_for_each_bio(bio, scmd->request) {
+ struct bio_integrity_payload *bip = bio_integrity(bio);
+ struct bio_vec iv;
+ struct bvec_iter iter;
+
+ virt = bip_get_seed(bip) & 0xffffffff;
+
+ bip_for_each_vec(iv, bip, iter) {
+ pi = kmap_atomic(iv.bv_page) + iv.bv_offset;
+
+ for (j = 0; j < iv.bv_len; j += tuple_sz, pi++) {
+
+ if (intervals == 0) {
+ kunmap_atomic(pi);
+ return;
+ }
+
+ if (be32_to_cpu(pi->ref_tag) == phys)
+ pi->ref_tag = cpu_to_be32(virt);
+
+ virt++;
+ phys++;
+ intervals--;
+ }
+
+ kunmap_atomic(pi);
+ }
+ }
+}
+