block: Inline blk_integrity in struct gendisk

Up until now the_integrity profile has been dynamically allocated and
attached to struct gendisk after the disk has been made active.

This causes problems because NVMe devices need to register the profile
prior to the partition table being read due to a mandatory metadata
buffer requirement. In addition, DM goes through hoops to deal with
preallocating, but not initializing integrity profiles.

Since the integrity profile is small (4 bytes + a pointer), Christoph
suggested moving it to struct gendisk proper. This requires several
changes:

 - Moving the blk_integrity definition to genhd.h.

 - Inlining blk_integrity in struct gendisk.

 - Removing the dynamic allocation code.

 - Adding helper functions which allow gendisk to set up and tear down
   the integrity sysfs dir when a disk is added/deleted.

 - Adding a blk_integrity_revalidate() callback for updating the stable
   pages bdi setting.

 - The calls that depend on whether a device has an integrity profile or
   not now key off of the bi->profile pointer.

 - Simplifying the integrity support routines in DM (Mike Snitzer).

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reported-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

2 files changed, 37 insertions, 23 deletions

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 4f1968f15e30..60669c20190f 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1468,16 +1468,7 @@ struct blk_integrity_profile {
 	const char			*name;
 };
 
-struct blk_integrity {
-	struct blk_integrity_profile	*profile;
-	unsigned char			flags;
-	unsigned char			tuple_size;
-	unsigned char			interval_exp;
-	unsigned char			tag_size;
-};
-
-extern bool blk_integrity_is_initialized(struct gendisk *);
-extern int blk_integrity_register(struct gendisk *, struct blk_integrity *);
+extern void blk_integrity_register(struct gendisk *, struct blk_integrity *);
 extern void blk_integrity_unregister(struct gendisk *);
 extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
@@ -1488,15 +1479,20 @@ extern bool blk_integrity_merge_rq(struct request_queue *, struct request *,
 extern bool blk_integrity_merge_bio(struct request_queue *, struct request *,
 				    struct bio *);
 
-static inline
-struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
+static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
 {
-	return bdev->bd_disk->integrity;
+	struct blk_integrity *bi = &disk->integrity;
+
+	if (!bi->profile)
+		return NULL;
+
+	return bi;
 }
 
-static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
+static inline
+struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
 {
-	return disk->integrity;
+	return blk_get_integrity(bdev->bd_disk);
 }
 
 static inline bool blk_integrity_rq(struct request *rq)
@@ -1570,10 +1566,9 @@ static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
 {
 	return 0;
 }
-static inline int blk_integrity_register(struct gendisk *d,
+static inline void blk_integrity_register(struct gendisk *d,
 					 struct blk_integrity *b)
 {
-	return 0;
 }
 static inline void blk_integrity_unregister(struct gendisk *d)
 {
@@ -1598,10 +1593,7 @@ static inline bool blk_integrity_merge_bio(struct request_queue *rq,
 {
 	return true;
 }
-static inline bool blk_integrity_is_initialized(struct gendisk *g)
-{
-	return 0;
-}
+
 static inline bool integrity_req_gap_back_merge(struct request *req,
 						struct bio *next)
 {
diff --git a/include/linux/genhd.h b/include/linux/genhd.h
index 9e6e0dfa97ad..82f4911e0ad8 100644
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -163,6 +163,18 @@ struct disk_part_tbl {
 
 struct disk_events;
 
+#if defined(CONFIG_BLK_DEV_INTEGRITY)
+
+struct blk_integrity {
+	struct blk_integrity_profile	*profile;
+	unsigned char			flags;
+	unsigned char			tuple_size;
+	unsigned char			interval_exp;
+	unsigned char			tag_size;
+};
+
+#endif	/* CONFIG_BLK_DEV_INTEGRITY */
+
 struct gendisk {
 	/* major, first_minor and minors are input parameters only,
 	 * don't use directly.  Use disk_devt() and disk_max_parts().
@@ -198,9 +210,9 @@ struct gendisk {
 	atomic_t sync_io;		/* RAID */
 	struct disk_events *ev;
 #ifdef  CONFIG_BLK_DEV_INTEGRITY
-	struct blk_integrity *integrity;
+	struct blk_integrity integrity;
 	struct kobject integrity_kobj;
-#endif
+#endif	/* CONFIG_BLK_DEV_INTEGRITY */
 	int node_id;
 };
 
@@ -728,6 +740,16 @@ static inline void part_nr_sects_write(struct hd_struct *part, sector_t size)
 #endif
 }
 
+#if defined(CONFIG_BLK_DEV_INTEGRITY)
+extern void blk_integrity_add(struct gendisk *);
+extern void blk_integrity_del(struct gendisk *);
+extern void blk_integrity_revalidate(struct gendisk *);
+#else	/* CONFIG_BLK_DEV_INTEGRITY */
+static inline void blk_integrity_add(struct gendisk *disk) { }
+static inline void blk_integrity_del(struct gendisk *disk) { }
+static inline void blk_integrity_revalidate(struct gendisk *disk) { }
+#endif	/* CONFIG_BLK_DEV_INTEGRITY */
+
 #else /* CONFIG_BLOCK */
 
 static inline void printk_all_partitions(void) { }