xfs: convert rt bitmap extent lengths to xfs_rtbxlen_t

XFS uses xfs_rtblock_t for many different uses, which makes it much more
difficult to perform a unit analysis on the codebase.  One of these
(ab)uses is when we need to store the length of a free space extent as
stored in the realtime bitmap.  Because there can be up to 2^64 realtime
extents in a filesystem, we need a new type that is larger than
xfs_rtxlen_t for callers that are querying the bitmap directly.  This
means scrub and growfs.

Create this type as "xfs_rtbxlen_t" and use it to store 64-bit rtx
lengths.  'b' stands for 'bitmap' or 'big'; reader's choice.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

fs/xfs/libxfs/xfs_format.h

@@ -98,7 +98,7 @@ typedef struct xfs_sb {
 	uint32_t	sb_blocksize;	/* logical block size, bytes */
 	xfs_rfsblock_t	sb_dblocks;	/* number of data blocks */
 	xfs_rfsblock_t	sb_rblocks;	/* number of realtime blocks */
-	xfs_rtblock_t	sb_rextents;	/* number of realtime extents */
+	xfs_rtbxlen_t	sb_rextents;	/* number of realtime extents */
 	uuid_t		sb_uuid;	/* user-visible file system unique id */
 	xfs_fsblock_t	sb_logstart;	/* starting block of log if internal */
 	xfs_ino_t	sb_rootino;	/* root inode number */

fs/xfs/libxfs/xfs_rtbitmap.h

@@ -13,7 +13,7 @@
  */
 struct xfs_rtalloc_rec {
 	xfs_rtblock_t		ar_startext;
-	xfs_rtblock_t		ar_extcount;
+	xfs_rtbxlen_t		ar_extcount;
 };
 
 typedef int (*xfs_rtalloc_query_range_fn)(

fs/xfs/libxfs/xfs_types.h

@@ -32,6 +32,7 @@ typedef uint64_t	xfs_rfsblock_t;	/* blockno in filesystem (raw) */
 typedef uint64_t	xfs_rtblock_t;	/* extent (block) in realtime area */
 typedef uint64_t	xfs_fileoff_t;	/* block number in a file */
 typedef uint64_t	xfs_filblks_t;	/* number of blocks in a file */
+typedef uint64_t	xfs_rtbxlen_t;	/* rtbitmap extent length in rtextents */
 
 typedef int64_t		xfs_srtblock_t;	/* signed version of xfs_rtblock_t */
 

fs/xfs/scrub/trace.h

@@ -1037,7 +1037,8 @@ TRACE_EVENT(xfarray_sort_stats,
 #ifdef CONFIG_XFS_RT
 TRACE_EVENT(xchk_rtsum_record_free,
 	TP_PROTO(struct xfs_mount *mp, xfs_rtblock_t start,
-		 uint64_t len, unsigned int log, loff_t pos, xfs_suminfo_t v),
+		 xfs_rtbxlen_t len, unsigned int log, loff_t pos,
+		 xfs_suminfo_t v),
 	TP_ARGS(mp, start, len, log, pos, v),
 	TP_STRUCT__entry(
 		__field(dev_t, dev)