libnvdimm, blk: add support for blk integrity

Support multiple block sizes (sector + metadata) for nd_blk in the
same way as done for the BTT. Add the idea of an 'internal' lbasize,
which is properly aligned and padded, and store metadata in this space.

Signed-off-by: Vishal Verma <vishal.l.verma@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

5 files changed, 159 insertions, 23 deletions

diff --git a/drivers/nvdimm/blk.c b/drivers/nvdimm/blk.c
index 9ac0c266c15c..5c44e067652f 100644
--- a/drivers/nvdimm/blk.c
+++ b/drivers/nvdimm/blk.c
@@ -27,10 +27,17 @@ struct nd_blk_device {
         struct nd_namespace_blk *nsblk;
         struct nd_blk_region *ndbr;
         size_t disk_size;
+        u32 sector_size;
+        u32 internal_lbasize;
 };
 
 static int nd_blk_major;
 
+static u32 nd_blk_meta_size(struct nd_blk_device *blk_dev)
+{
+        return blk_dev->nsblk->lbasize - blk_dev->sector_size;
+}
+
 static resource_size_t to_dev_offset(struct nd_namespace_blk *nsblk,
                                 resource_size_t ns_offset, unsigned int len)
 {
@@ -52,41 +59,145 @@ static resource_size_t to_dev_offset(struct nd_namespace_blk *nsblk,
         return SIZE_MAX;
 }
 
+#ifdef CONFIG_BLK_DEV_INTEGRITY
+static int nd_blk_rw_integrity(struct nd_blk_device *blk_dev,
+                                struct bio_integrity_payload *bip, u64 lba,
+                                int rw)
+{
+        unsigned int len = nd_blk_meta_size(blk_dev);
+        resource_size_t dev_offset, ns_offset;
+        struct nd_namespace_blk *nsblk;
+        struct nd_blk_region *ndbr;
+        int err = 0;
+
+        nsblk = blk_dev->nsblk;
+        ndbr = blk_dev->ndbr;
+        ns_offset = lba * blk_dev->internal_lbasize + blk_dev->sector_size;
+        dev_offset = to_dev_offset(nsblk, ns_offset, len);
+        if (dev_offset == SIZE_MAX)
+                return -EIO;
+
+        while (len) {
+                unsigned int cur_len;
+                struct bio_vec bv;
+                void *iobuf;
+
+                bv = bvec_iter_bvec(bip->bip_vec, bip->bip_iter);
+                /*
+                 * The 'bv' obtained from bvec_iter_bvec has its .bv_len and
+                 * .bv_offset already adjusted for iter->bi_bvec_done, and we
+                 * can use those directly
+                 */
+
+                cur_len = min(len, bv.bv_len);
+                iobuf = kmap_atomic(bv.bv_page);
+                err = ndbr->do_io(ndbr, dev_offset, iobuf + bv.bv_offset,
+                                cur_len, rw);
+                kunmap_atomic(iobuf);
+                if (err)
+                        return err;
+
+                len -= cur_len;
+                dev_offset += cur_len;
+                bvec_iter_advance(bip->bip_vec, &bip->bip_iter, cur_len);
+        }
+
+        return err;
+}
+
+#else /* CONFIG_BLK_DEV_INTEGRITY */
+static int nd_blk_rw_integrity(struct nd_blk_device *blk_dev,
+                                struct bio_integrity_payload *bip, u64 lba,
+                                int rw)
+{
+        return 0;
+}
+#endif
+
+static int nd_blk_do_bvec(struct nd_blk_device *blk_dev,
+                        struct bio_integrity_payload *bip, struct page *page,
+                        unsigned int len, unsigned int off, int rw,
+                        sector_t sector)
+{
+        struct nd_blk_region *ndbr = blk_dev->ndbr;
+        resource_size_t dev_offset, ns_offset;
+        int err = 0;
+        void *iobuf;
+        u64 lba;
+
+        while (len) {
+                unsigned int cur_len;
+
+                /*
+                 * If we don't have an integrity payload, we don't have to
+                 * split the bvec into sectors, as this would cause unnecessary
+                 * Block Window setup/move steps. the do_io routine is capable
+                 * of handling len <= PAGE_SIZE.
+                 */
+                cur_len = bip ? min(len, blk_dev->sector_size) : len;
+
+                lba = div_u64(sector << SECTOR_SHIFT, blk_dev->sector_size);
+                ns_offset = lba * blk_dev->internal_lbasize;
+                dev_offset = to_dev_offset(blk_dev->nsblk, ns_offset, cur_len);
+                if (dev_offset == SIZE_MAX)
+                        return -EIO;
+
+                iobuf = kmap_atomic(page);
+                err = ndbr->do_io(ndbr, dev_offset, iobuf + off, cur_len, rw);
+                kunmap_atomic(iobuf);
+                if (err)
+                        return err;
+
+                if (bip) {
+                        err = nd_blk_rw_integrity(blk_dev, bip, lba, rw);
+                        if (err)
+                                return err;
+                }
+                len -= cur_len;
+                off += cur_len;
+                sector += blk_dev->sector_size >> SECTOR_SHIFT;
+        }
+
+        return err;
+}
+
 static void nd_blk_make_request(struct request_queue *q, struct bio *bio)
 {
         struct block_device *bdev = bio->bi_bdev;
         struct gendisk *disk = bdev->bd_disk;
-        struct nd_namespace_blk *nsblk;
+        struct bio_integrity_payload *bip;
         struct nd_blk_device *blk_dev;
-        struct nd_blk_region *ndbr;
         struct bvec_iter iter;
         struct bio_vec bvec;
         int err = 0, rw;
 
+        /*
+         * bio_integrity_enabled also checks if the bio already has an
+         * integrity payload attached. If it does, we *don't* do a
+         * bio_integrity_prep here - the payload has been generated by
+         * another kernel subsystem, and we just pass it through.
+         */
+        if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) {
+                err = -EIO;
+                goto out;
+        }
+
+        bip = bio_integrity(bio);
         blk_dev = disk->private_data;
-        nsblk = blk_dev->nsblk;
-        ndbr = blk_dev->ndbr;
         rw = bio_data_dir(bio);
         bio_for_each_segment(bvec, bio, iter) {
                 unsigned int len = bvec.bv_len;
-                resource_size_t dev_offset;
-                void *iobuf;
 
                 BUG_ON(len > PAGE_SIZE);
-
-                dev_offset = to_dev_offset(nsblk,
-                                iter.bi_sector << SECTOR_SHIFT, len);
-                if (dev_offset == SIZE_MAX) {
-                        err = -EIO;
+                err = nd_blk_do_bvec(blk_dev, bip, bvec.bv_page, len,
+                                        bvec.bv_offset, rw, iter.bi_sector);
+                if (err) {
+                        dev_info(&blk_dev->nsblk->common.dev,
+                                        "io error in %s sector %lld, len %d,\n",
+                                        (rw == READ) ? "READ" : "WRITE",
+                                        (unsigned long long) iter.bi_sector, len);
                         goto out;
                 }
-
-                iobuf = kmap_atomic(bvec.bv_page);
-                err = ndbr->do_io(ndbr, dev_offset, iobuf + bvec.bv_offset,
-                                len, rw);
-                kunmap_atomic(iobuf);
-                if (err)
-                        goto out;
         }
 
  out:
@@ -121,8 +232,12 @@ static const struct block_device_operations nd_blk_fops = {
 static int nd_blk_attach_disk(struct nd_namespace_common *ndns,
                 struct nd_blk_device *blk_dev)
 {
-        struct nd_namespace_blk *nsblk = to_nd_namespace_blk(&ndns->dev);
+        resource_size_t available_disk_size;
         struct gendisk *disk;
+        u64 internal_nlba;
+
+        internal_nlba = div_u64(blk_dev->disk_size, blk_dev->internal_lbasize);
+        available_disk_size = internal_nlba * blk_dev->sector_size;
 
         blk_dev->queue = blk_alloc_queue(GFP_KERNEL);
         if (!blk_dev->queue)
@@ -131,7 +246,7 @@ static int nd_blk_attach_disk(struct nd_namespace_common *ndns,
         blk_queue_make_request(blk_dev->queue, nd_blk_make_request);
         blk_queue_max_hw_sectors(blk_dev->queue, UINT_MAX);
         blk_queue_bounce_limit(blk_dev->queue, BLK_BOUNCE_ANY);
-        blk_queue_logical_block_size(blk_dev->queue, nsblk->lbasize);
+        blk_queue_logical_block_size(blk_dev->queue, blk_dev->sector_size);
         queue_flag_set_unlocked(QUEUE_FLAG_NONROT, blk_dev->queue);
 
         disk = blk_dev->disk = alloc_disk(0);
@@ -148,15 +263,28 @@ static int nd_blk_attach_disk(struct nd_namespace_common *ndns,
         disk->queue             = blk_dev->queue;
         disk->flags             = GENHD_FL_EXT_DEVT;
         nvdimm_namespace_disk_name(ndns, disk->disk_name);
-        set_capacity(disk, blk_dev->disk_size >> SECTOR_SHIFT);
+        set_capacity(disk, 0);
         add_disk(disk);
 
+        if (nd_blk_meta_size(blk_dev)) {
+                int rc = nd_integrity_init(disk, nd_blk_meta_size(blk_dev));
+
+                if (rc) {
+                        del_gendisk(disk);
+                        put_disk(disk);
+                        blk_cleanup_queue(blk_dev->queue);
+                        return rc;
+                }
+        }
+
+        set_capacity(disk, available_disk_size >> SECTOR_SHIFT);
         return 0;
 }
 
 static int nd_blk_probe(struct device *dev)
 {
         struct nd_namespace_common *ndns;
+        struct nd_namespace_blk *nsblk;
         struct nd_blk_device *blk_dev;
         int rc;
 
@@ -168,9 +296,13 @@ static int nd_blk_probe(struct device *dev)
         if (!blk_dev)
                 return -ENOMEM;
 
+        nsblk = to_nd_namespace_blk(&ndns->dev);
         blk_dev->disk_size = nvdimm_namespace_capacity(ndns);
         blk_dev->ndbr = to_nd_blk_region(dev->parent);
         blk_dev->nsblk = to_nd_namespace_blk(&ndns->dev);
+        blk_dev->internal_lbasize = roundup(nsblk->lbasize,
+                                                INT_LBASIZE_ALIGNMENT);
+        blk_dev->sector_size = ((nsblk->lbasize >= 4096) ? 4096 : 512);
         dev_set_drvdata(dev, blk_dev);
 
         ndns->rw_bytes = nd_blk_rw_bytes;
diff --git a/drivers/nvdimm/btt.h b/drivers/nvdimm/btt.h
index 2caa0ef7e67a..75b0d80a6bd9 100644
--- a/drivers/nvdimm/btt.h
+++ b/drivers/nvdimm/btt.h
@@ -31,7 +31,6 @@
 #define ARENA_MAX_SIZE (1ULL << 39)     /* 512 GB */
 #define RTT_VALID (1UL << 31)
 #define RTT_INVALID 0
-#define INT_LBASIZE_ALIGNMENT 64
 #define BTT_PG_SIZE 4096
 #define BTT_DEFAULT_NFREE ND_MAX_LANES
 #define LOG_SEQ_INIT 1
diff --git a/drivers/nvdimm/core.c b/drivers/nvdimm/core.c
index 1d96b9a6e4cc..4288169432de 100644
--- a/drivers/nvdimm/core.c
+++ b/drivers/nvdimm/core.c
@@ -379,6 +379,9 @@ int nd_integrity_init(struct gendisk *disk, unsigned long meta_size)
         };
         int ret;
 
+        if (meta_size == 0)
+                return 0;
+
         ret = blk_integrity_register(disk, &integrity);
         if (ret)
                 return ret;
diff --git a/drivers/nvdimm/namespace_devs.c b/drivers/nvdimm/namespace_devs.c
index 1ce1e70de44a..27d69bd3b4d6 100644
--- a/drivers/nvdimm/namespace_devs.c
+++ b/drivers/nvdimm/namespace_devs.c
@@ -1059,7 +1059,8 @@ static ssize_t resource_show(struct device *dev,
 }
 static DEVICE_ATTR_RO(resource);
 
-static const unsigned long ns_lbasize_supported[] = { 512, 0 };
+static const unsigned long ns_lbasize_supported[] = { 512, 520, 528,
+        4096, 4104, 4160, 4224, 0 };
 
 static ssize_t sector_size_show(struct device *dev,
                 struct device_attribute *attr, char *buf)
diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h
index f4459faa456c..6f916b65b7d6 100644
--- a/drivers/nvdimm/nd.h
+++ b/drivers/nvdimm/nd.h
@@ -27,6 +27,7 @@ enum {
          */
         ND_MAX_LANES = 256,
         SECTOR_SHIFT = 9,
+        INT_LBASIZE_ALIGNMENT = 64,
 };
 
 struct nvdimm_drvdata {