[PATCH 09/15] libnvdimm, blk: add support for blk integrity

Dan Williams
2015-06-17T23:55:35Z

From: Vishal Verma <vishal.l.verma@linux.intel.com>

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>
---
drivers/nvdimm/blk.c | 168 ++++++++++++++++++++++++++++++++++-----
drivers/nvdimm/btt.h | 1
drivers/nvdimm/bus.c | 28 +++++--
drivers/nvdimm/core.c | 3 +
drivers/nvdimm/namespace_devs.c | 3 -
drivers/nvdimm/nd.h | 3 +
6 files changed, 174 insertions(+), 32 deletions(-)

diff --git a/drivers/nvdimm/blk.c b/drivers/nvdimm/blk.c
index a2749b5e43d7..feddad325f97 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)
{
@@ -52,13 +59,114 @@ 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;
@@ -74,29 +182,33 @@ static void nd_blk_make_request(struct request_queue *q, struct bio *bio)

rw = bio_data_dir(bio);

+ /*
+ * 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;
+
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, 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, sector);
+ if (err) {
+ dev_info(&blk_dev->nsblk->dev,
+ "io error in %s sector %lld, len %d,\n",
+ (rw == READ) ? "READ" : "WRITE",
+ (unsigned long long) 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;
-
sector += len >> SECTOR_SHIFT;
}

@@ -135,7 +247,8 @@ static int nd_blk_probe(struct device *dev)
struct nd_namespace_blk *nsblk = to_nd_namespace_blk(dev);
struct nd_region *nd_region = to_nd_region(dev->parent);
struct nd_blk_device *blk_dev;
- resource_size_t disk_size;
+ resource_size_t disk_size, available_disk_size;
+ u64 internal_nlba;
struct gendisk *disk;
int err;

@@ -148,6 +261,9 @@ static int nd_blk_probe(struct device *dev)
return -ENOMEM;

blk_dev->disk_size = disk_size;
+ blk_dev->sector_size = ((nsblk->lbasize >= 4096) ? 4096 : 512);
+ blk_dev->internal_lbasize = roundup(nsblk->lbasize,
+ INT_LBASIZE_ALIGNMENT);

blk_dev->queue = blk_alloc_queue(GFP_KERNEL);
if (!blk_dev->queue) {
@@ -158,7 +274,7 @@ static int nd_blk_probe(struct device *dev)
blk_queue_make_request(blk_dev->queue, nd_blk_make_request);
blk_queue_max_hw_sectors(blk_dev->queue, 1024);
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);

disk = blk_dev->disk = alloc_disk(0);
if (!disk) {
@@ -177,13 +293,21 @@ static int nd_blk_probe(struct device *dev)
disk->queue = blk_dev->queue;
disk->flags = GENHD_FL_EXT_DEVT;
sprintf(disk->disk_name, "ndblk%d.%d", nd_region->id, nsblk->id);
- set_capacity(disk, disk_size >> SECTOR_SHIFT);
+ set_capacity(disk, 0);

+ internal_nlba = div_u64(disk_size, blk_dev->internal_lbasize);
+ available_disk_size = internal_nlba * blk_dev->sector_size;
dev_set_drvdata(dev, blk_dev);
- nvdimm_bus_add_disk(disk);
+ err = nvdimm_bus_add_integrity_disk(disk, nd_blk_meta_size(blk_dev),
+ available_disk_size >> SECTOR_SHIFT);
+ if (err)
+ goto err_add_disk;

return 0;

+ err_add_disk:
+ del_gendisk(disk);
+ put_disk(disk);
err_alloc_disk:
blk_cleanup_queue(blk_dev->queue);
err_alloc_queue:
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/bus.c b/drivers/nvdimm/bus.c
index 3c14fee5aff4..d4fbc48f5643 100644
--- a/drivers/nvdimm/bus.c
+++ b/drivers/nvdimm/bus.c
@@ -243,17 +243,13 @@ int __nd_driver_register(struct nd_device_driver *nd_drv, struct module *owner,
}
EXPORT_SYMBOL(__nd_driver_register);

-/**
- * nvdimm_bus_add_disk() - attach and run actions on an nvdimm block device
- * @disk: disk device being registered
- *
- * Note, that @disk must be a descendant of an nvdimm_bus
- */
-int nvdimm_bus_add_disk(struct gendisk *disk)
+int nvdimm_bus_add_integrity_disk(struct gendisk *disk, u32 lbasize,
+ sector_t size)
{
const struct block_device_operations *ops = disk->fops;
struct device *dev = disk->driverfs_dev;
struct nvdimm_bus *nvdimm_bus;
+ int rc;

nvdimm_bus = walk_to_nvdimm_bus(dev);
if (!nvdimm_bus || !ops->rw_bytes)
@@ -266,10 +262,25 @@ int nvdimm_bus_add_disk(struct gendisk *disk)
*/
nvdimm_bus_lock(&nvdimm_bus->dev);
add_disk(disk);
+ rc = nd_integrity_init(disk, lbasize);
+ if (size)
+ set_capacity(disk, size);
nd_btt_add_disk(nvdimm_bus, disk);
nvdimm_bus_unlock(&nvdimm_bus->dev);

- return 0;
+ return rc;
+}
+EXPORT_SYMBOL(nvdimm_bus_add_integrity_disk);
+
+/**
+ * nvdimm_bus_add_disk() - attach and run actions on an nvdimm block device
+ * @disk: disk device being registered
+ *
+ * Note, that @disk must be a descendant of an nvdimm_bus
+ */
+int nvdimm_bus_add_disk(struct gendisk *disk)
+{
+ return nvdimm_bus_add_integrity_disk(disk, 0, 0);
}
EXPORT_SYMBOL(nvdimm_bus_add_disk);

@@ -292,6 +303,7 @@ void nvdimm_bus_remove_disk(struct gendisk *disk)
*/
nd_synchronize();

+ blk_integrity_unregister(disk);
del_gendisk(disk);
put_disk(disk);
}
diff --git a/drivers/nvdimm/core.c b/drivers/nvdimm/core.c
index 36f112995c0c..8f466c384b30 100644
--- a/drivers/nvdimm/core.c
+++ b/drivers/nvdimm/core.c
@@ -399,6 +399,9 @@ 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 68780d768e7b..0fe541a1df49 100644
--- a/drivers/nvdimm/namespace_devs.c
+++ b/drivers/nvdimm/namespace_devs.c
@@ -1013,7 +1013,8 @@ 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 1cea3f191a83..9b5fdb2215b1 100644
--- a/drivers/nvdimm/nd.h
+++ b/drivers/nvdimm/nd.h
@@ -29,6 +29,7 @@ enum {
*/
ND_MAX_LANES = 256,
SECTOR_SHIFT = 9,
+ INT_LBASIZE_ALIGNMENT = 64,
};

struct nvdimm_drvdata {
@@ -159,6 +160,8 @@ void nvdimm_bus_lock(struct device *dev);
void nvdimm_bus_unlock(struct device *dev);
bool is_nvdimm_bus_locked(struct device *dev);
int nvdimm_bus_add_disk(struct gendisk *disk);
+int nvdimm_bus_add_integrity_disk(struct gendisk *disk, u32 lbasize,
+ sector_t size);
void nvdimm_bus_remove_disk(struct gendisk *disk);
void nvdimm_drvdata_release(struct kref *kref);
void put_ndd(struct nvdimm_drvdata *ndd);