target/iblock: Add blk_integrity + BIP passthrough support

This patch adds blk_integrity passthrough support for block_device
backends using IBLOCK.

This includes iblock_alloc_bip() + setup of bio_integrity_payload
information that attaches to the leading struct bio once bio_list
is populated during fast-path iblock_execute_rw() I/O dispatch.

It also updates setup in iblock_configure_device() to detect modes
of protection + se dev->dev_attrib.pi_prot_type accordingly, along
with creating required bio_set integrity mempools.

Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

diff --git a/drivers/target/Kconfig b/drivers/target/Kconfig
index 50aad2e..dc2d84a 100644 (file)
--- a/drivers/target/Kconfig
+++ b/drivers/target/Kconfig
@@ -14,6 +14,7 @@ if TARGET_CORE
 
 config TCM_IBLOCK
        tristate "TCM/IBLOCK Subsystem Plugin for Linux/BLOCK"
+       select BLK_DEV_INTEGRITY
        help
        Say Y here to enable the TCM/IBLOCK subsystem plugin for non-buffered
        access to Linux/Block devices using BIO

diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c
index 15d9121..293d9b0 100644 (file)
--- a/drivers/target/target_core_iblock.c
+++ b/drivers/target/target_core_iblock.c
@@ -91,6 +91,7 @@ static int iblock_configure_device(struct se_device *dev)
        struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
        struct request_queue *q;
        struct block_device *bd = NULL;
+       struct blk_integrity *bi;
        fmode_t mode;
        int ret = -ENOMEM;
 
@@ -155,8 +156,40 @@ static int iblock_configure_device(struct se_device *dev)
        if (blk_queue_nonrot(q))
                dev->dev_attrib.is_nonrot = 1;
 
+       bi = bdev_get_integrity(bd);
+       if (bi) {
+               struct bio_set *bs = ib_dev->ibd_bio_set;
+
+               if (!strcmp(bi->name, "T10-DIF-TYPE3-IP") ||
+                   !strcmp(bi->name, "T10-DIF-TYPE1-IP")) {
+                       pr_err("IBLOCK export of blk_integrity: %s not"
+                              " supported\n", bi->name);
+                       ret = -ENOSYS;
+                       goto out_blkdev_put;
+               }
+
+               if (!strcmp(bi->name, "T10-DIF-TYPE3-CRC")) {
+                       dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE3_PROT;
+               } else if (!strcmp(bi->name, "T10-DIF-TYPE1-CRC")) {
+                       dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE1_PROT;
+               }
+
+               if (dev->dev_attrib.pi_prot_type) {
+                       if (bioset_integrity_create(bs, IBLOCK_BIO_POOL_SIZE) < 0) {
+                               pr_err("Unable to allocate bioset for PI\n");
+                               ret = -ENOMEM;
+                               goto out_blkdev_put;
+                       }
+                       pr_debug("IBLOCK setup BIP bs->bio_integrity_pool: %p\n",
+                                bs->bio_integrity_pool);
+               }
+               dev->dev_attrib.hw_pi_prot_type = dev->dev_attrib.pi_prot_type;
+       }
+
        return 0;
 
+out_blkdev_put:
+       blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
 out_free_bioset:
        bioset_free(ib_dev->ibd_bio_set);
        ib_dev->ibd_bio_set = NULL;
@@ -170,8 +203,10 @@ static void iblock_free_device(struct se_device *dev)
 
        if (ib_dev->ibd_bd != NULL)
                blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
-       if (ib_dev->ibd_bio_set != NULL)
+       if (ib_dev->ibd_bio_set != NULL) {
+               bioset_integrity_free(ib_dev->ibd_bio_set);
                bioset_free(ib_dev->ibd_bio_set);
+       }
        kfree(ib_dev);
 }
 
@@ -586,13 +621,58 @@ static ssize_t iblock_show_configfs_dev_params(struct se_device *dev, char *b)
        return bl;
 }
 
+static int
+iblock_alloc_bip(struct se_cmd *cmd, struct bio *bio)
+{
+       struct se_device *dev = cmd->se_dev;
+       struct blk_integrity *bi;
+       struct bio_integrity_payload *bip;
+       struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
+       struct scatterlist *sg;
+       int i, rc;
+
+       bi = bdev_get_integrity(ib_dev->ibd_bd);
+       if (!bi) {
+               pr_err("Unable to locate bio_integrity\n");
+               return -ENODEV;
+       }
+
+       bip = bio_integrity_alloc(bio, GFP_NOIO, cmd->t_prot_nents);
+       if (!bip) {
+               pr_err("Unable to allocate bio_integrity_payload\n");
+               return -ENOMEM;
+       }
+
+       bip->bip_size = (cmd->data_length / dev->dev_attrib.block_size) *
+                        dev->prot_length;
+       bip->bip_sector = bio->bi_sector;
+
+       pr_debug("IBLOCK BIP Size: %u Sector: %llu\n", bip->bip_size,
+                (unsigned long long)bip->bip_sector);
+
+       for_each_sg(cmd->t_prot_sg, sg, cmd->t_prot_nents, i) {
+
+               rc = bio_integrity_add_page(bio, sg_page(sg), sg->length,
+                                           sg->offset);
+               if (rc != sg->length) {
+                       pr_err("bio_integrity_add_page() failed; %d\n", rc);
+                       return -ENOMEM;
+               }
+
+               pr_debug("Added bio integrity page: %p length: %d offset; %d\n",
+                        sg_page(sg), sg->length, sg->offset);
+       }
+
+       return 0;
+}
+
 static sense_reason_t
 iblock_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
                  enum dma_data_direction data_direction)
 {
        struct se_device *dev = cmd->se_dev;
        struct iblock_req *ibr;
-       struct bio *bio;
+       struct bio *bio, *bio_start;
        struct bio_list list;
        struct scatterlist *sg;
        u32 sg_num = sgl_nents;
@@ -655,6 +735,7 @@ iblock_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
        if (!bio)
                goto fail_free_ibr;
 
+       bio_start = bio;
        bio_list_init(&list);
        bio_list_add(&list, bio);
 
@@ -688,6 +769,12 @@ iblock_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
                sg_num--;
        }
 
+       if (cmd->prot_type) {
+               int rc = iblock_alloc_bip(cmd, bio_start);
+               if (rc)
+                       goto fail_put_bios;
+       }
+
        iblock_submit_bios(&list, rw);
        iblock_complete_cmd(cmd);
        return 0;