[patch] minix zmap block counts calculation fix

[patch] minix zmap block counts calculation fix

[Qi Yong]

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Hello,

The original Linus' minix zmap blocks calculation was correct, in the
formula of: sbi->s_nzones - sbi->s_firstdatazone + 1. It is (sp->s_zones
- (sp->s_firstdatazone - 1) in the minix3 source code.

But a later patch (fs/minix: Verify bitmap block counts before mounting)
has changed it unfortunately as:
  sbi->s_nzones - (sbi->s_firstdatazone + 1).
This would show free blocks one block less than the real when the total
data blocks are in "full zmap blocks plus one".

commit 016e8d44bc06dd3322f26712bdd3f3a6973592d0
Author: Josh Boyer <jwboyer@redhat.com>
Date:   Fri Aug 19 14:50:26 2011 -0400

This patch corrects that zmap blocks calculation and tidy a printk
message while at it.

Signed-off-by: Qi Yong <qiyong@fc-cn.com>

-- 
Qi Yong


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diff --git a/fs/minix/bitmap.c b/fs/minix/bitmap.c
index 4bc50da..742942a 100644
--- a/fs/minix/bitmap.c
+++ b/fs/minix/bitmap.c
@@ -96,7 +96,7 @@ int minix_new_block(struct inode * inode)
 unsigned long minix_count_free_blocks(struct super_block *sb)
 {
 	struct minix_sb_info *sbi = minix_sb(sb);
-	u32 bits = sbi->s_nzones - (sbi->s_firstdatazone + 1);
+	u32 bits = sbi->s_nzones - sbi->s_firstdatazone + 1;
 
 	return (count_free(sbi->s_zmap, sb->s_blocksize, bits)
 		<< sbi->s_log_zone_size);
diff --git a/fs/minix/inode.c b/fs/minix/inode.c
index f007a33..3f57af1 100644
--- a/fs/minix/inode.c
+++ b/fs/minix/inode.c
@@ -267,12 +267,12 @@ static int minix_fill_super(struct super_block *s, void *data, int silent)
 	block = minix_blocks_needed(sbi->s_ninodes, s->s_blocksize);
 	if (sbi->s_imap_blocks < block) {
 		printk("MINIX-fs: file system does not have enough "
-				"imap blocks allocated.  Refusing to mount\n");
+				"imap blocks allocated.  Refusing to mount.\n");
 		goto out_no_bitmap;
 	}
 
 	block = minix_blocks_needed(
-			(sbi->s_nzones - (sbi->s_firstdatazone + 1)),
+			(sbi->s_nzones - sbi->s_firstdatazone + 1),
 			s->s_blocksize);
 	if (sbi->s_zmap_blocks < block) {
 		printk("MINIX-fs: file system does not have enough "