super1: separate to version of _avail_space1().

_avail_space1() is calls from both avail_space1() and validate_geometry1()
and does slightly different things.

The partial code sharing doesn't really help.  In particularly the
responsibility for setting the size of the array is currently
confused.

So duplicate the code into the two locations - one where 'super' is
always NULL (validate_geometry1) and one where it is never NULL
(avail_space1), and simplify.

No behaviour change - just code re-organisation.

Signed-off-by: NeilBrown <neilb@suse.de>

1 files changed, 63 insertions, 28 deletions

diff --git a/super1.c b/super1.c
index f8404597..f532bd2e 100644
--- a/super1.c
+++ b/super1.c
@@ -1992,19 +1992,16 @@ static struct supertype *match_metadata_desc1(char *arg)
  * superblock type st, and reserving 'reserve' sectors for
  * a possible bitmap
  */
-static __u64 _avail_size1(struct supertype *st, __u64 devsize,
-			  unsigned long long data_offset, int chunksize)
+static __u64 avail_size1(struct supertype *st, __u64 devsize,
+			 unsigned long long data_offset)
 {
 	struct mdp_superblock_1 *super = st->sb;
 	int bmspace = 0;
 	if (devsize < 24)
 		return 0;
 
-	if (super == NULL)
-		/* creating:  allow suitable space for bitmap */
-		bmspace = choose_bm_space(devsize);
 #ifndef MDASSEMBLE
-	else if (__le32_to_cpu(super->feature_map)&MD_FEATURE_BITMAP_OFFSET) {
+	if (__le32_to_cpu(super->feature_map)&MD_FEATURE_BITMAP_OFFSET) {
 		/* hot-add. allow for actual size of bitmap */
 		struct bitmap_super_s *bsb;
 		bsb = (struct bitmap_super_s *)(((char*)super)+MAX_SB_SIZE);
@@ -2012,10 +2009,8 @@ static __u64 _avail_size1(struct supertype *st, __u64 devsize,
 	}
 #endif
 	/* Allow space for bad block log */
-	if (super && super->bblog_size)
+	if (super->bblog_size)
 		devsize -= __le16_to_cpu(super->bblog_size);
-	else
-		devsize -= 8;
 
 	if (st->minor_version < 0)
 		/* not specified, so time to set default */
@@ -2034,18 +2029,6 @@ static __u64 _avail_size1(struct supertype *st, __u64 devsize,
 
 	devsize -= bmspace;
 
-	if (super == NULL && st->minor_version > 0) {
-		/* haven't committed to a size yet, so allow some
-		 * slack for space for reshape.
-		 * Limit slack to 128M, but aim for about 0.1%
-		 */
-		unsigned long long headroom = 128*1024*2;
-		while ((headroom << 10) > devsize &&
-		       (chunksize == 0 ||
-			headroom / 2 >= ((unsigned)chunksize*2)*2))
-			headroom >>= 1;
-		devsize -= headroom;
-	}
 	switch(st->minor_version) {
 	case 0:
 		/* at end */
@@ -2059,11 +2042,6 @@ static __u64 _avail_size1(struct supertype *st, __u64 devsize,
 	}
 	return 0;
 }
-static __u64 avail_size1(struct supertype *st, __u64 devsize,
-			 unsigned long long data_offset)
-{
-	return _avail_size1(st, devsize, data_offset, 0);
-}
 
 static int
 add_internal_bitmap1(struct supertype *st,
@@ -2294,7 +2272,8 @@ static int validate_geometry1(struct supertype *st, int level,
 			      char *subdev, unsigned long long *freesize,
 			      int verbose)
 {
-	unsigned long long ldsize;
+	unsigned long long ldsize, devsize;
+	int bmspace;
 	int fd;
 
 	if (level == LEVEL_CONTAINER) {
@@ -2322,7 +2301,63 @@ static int validate_geometry1(struct supertype *st, int level,
 	}
 	close(fd);
 
-	*freesize = _avail_size1(st, ldsize >> 9, data_offset, *chunk);
+	devsize = ldsize >> 9;
+	if (devsize < 24) {
+		*freesize = 0;
+		return 0;
+	}
+
+	/* creating:  allow suitable space for bitmap */
+	bmspace = choose_bm_space(devsize);
+	/* Allow space for bad block log */
+	devsize -= 8;
+
+	if (st->minor_version < 0)
+		/* not specified, so time to set default */
+		st->minor_version = 2;
+
+	if (data_offset != INVALID_SECTORS)
+		switch(st->minor_version) {
+		case 0:
+			*freesize = devsize - data_offset - 8*2;
+			return 1;
+		case 1:
+		case 2:
+			*freesize = devsize - data_offset;
+			return 1;
+		default:
+			return 0;
+		}
+	else {
+		devsize -= bmspace;
+
+		if (st->minor_version > 0) {
+			/* haven't committed to a size yet, so allow some
+			 * slack for space for reshape.
+			 * Limit slack to 128M, but aim for about 0.1%
+			 */
+			unsigned long long headroom = 128*1024*2;
+			while ((headroom << 10) > devsize &&
+			       (*chunk == 0 ||
+				headroom / 2 >= ((unsigned)(*chunk)*2)*2))
+				headroom >>= 1;
+			devsize -= headroom;
+		}
+		switch(st->minor_version) {
+		case 0:
+			/* at end */
+			*freesize = ((devsize - 8*2 ) & ~(4*2-1));
+			break;
+		case 1:
+			/* at start, 4K for superblock and possible bitmap */
+			*freesize = devsize - 4*2;
+			break;
+		case 2:
+			/* 4k from start, 4K for superblock and possible bitmap */
+			*freesize = devsize - (4+4)*2;
+			break;
+		}
+	}
 	return 1;
 }
 #endif /* MDASSEMBLE */