[PATCH 3/3] fs/ntfs3: Refactoring of ntfs_init_from_boot

[Konstantin Komarov <almaz.alexandrovich@paragon-software.com>]

Remove ntfs_sb_info members sector_size and sector_bits.
Print details why mount failed.

Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
---
 fs/ntfs3/ntfs_fs.h |  2 --
 fs/ntfs3/super.c   | 32 +++++++++++++++++++-------------
 2 files changed, 19 insertions(+), 15 deletions(-)

diff --git a/fs/ntfs3/ntfs_fs.h b/fs/ntfs3/ntfs_fs.h
index 6731b5d9e2d8..38b7c1a9dc52 100644
--- a/fs/ntfs3/ntfs_fs.h
+++ b/fs/ntfs3/ntfs_fs.h
@@ -211,10 +211,8 @@ struct ntfs_sb_info {
 	u32 blocks_per_cluster; // cluster_size / sb->s_blocksize
 
 	u32 record_size;
-	u32 sector_size;
 	u32 index_size;
 
-	u8 sector_bits;
 	u8 cluster_bits;
 	u8 record_bits;
 
diff --git a/fs/ntfs3/super.c b/fs/ntfs3/super.c
index 193f9a98f6ab..5fe9484c6781 100644
--- a/fs/ntfs3/super.c
+++ b/fs/ntfs3/super.c
@@ -682,7 +682,7 @@ static int ntfs_init_from_boot(struct super_block *sb, u32 sector_size,
 	struct ntfs_sb_info *sbi = sb->s_fs_info;
 	int err;
 	u32 mb, gb, boot_sector_size, sct_per_clst, record_size;
-	u64 sectors, clusters, fs_size, mlcn, mlcn2;
+	u64 sectors, clusters, mlcn, mlcn2;
 	struct NTFS_BOOT *boot;
 	struct buffer_head *bh;
 	struct MFT_REC *rec;
@@ -740,20 +740,20 @@ static int ntfs_init_from_boot(struct super_block *sb, u32 sector_size,
 		goto out;
 	}
 
-	sbi->sector_size = boot_sector_size;
-	sbi->sector_bits = blksize_bits(boot_sector_size);
-	fs_size = (sectors + 1) << sbi->sector_bits;
+	sbi->volume.size = sectors * boot_sector_size;
 
-	gb = format_size_gb(fs_size, &mb);
+	gb = format_size_gb(sbi->volume.size + boot_sector_size, &mb);
 
 	/*
 	 * - Volume formatted and mounted with the same sector size.
 	 * - Volume formatted 4K and mounted as 512.
 	 * - Volume formatted 512 and mounted as 4K.
 	 */
-	if (sbi->sector_size != sector_size) {
-		ntfs_warn(sb,
-			  "Different NTFS' sector size and media sector size");
+	if (boot_sector_size != sector_size) {
+		ntfs_warn(
+			sb,
+			"Different NTFS' sector size (%u) and media sector size (%u)",
+			boot_sector_size, sector_size);
 		dev_size += sector_size - 1;
 	}
 
@@ -764,12 +764,19 @@ static int ntfs_init_from_boot(struct super_block *sb, u32 sector_size,
 	sbi->mft.lbo2 = mlcn2 << sbi->cluster_bits;
 
 	/* Compare boot's cluster and sector. */
-	if (sbi->cluster_size < sbi->sector_size)
+	if (sbi->cluster_size < boot_sector_size)
 		goto out;
 
 	/* Compare boot's cluster and media sector. */
-	if (sbi->cluster_size < sector_size)
-		goto out; /* No way to use ntfs_get_block in this case. */
+	if (sbi->cluster_size < sector_size) {
+		/* No way to use ntfs_get_block in this case. */
+		ntfs_err(
+			sb,
+			"Failed to mount 'cause NTFS's cluster size (%u) is "
+			"less than media sector size (%u)",
+			sbi->cluster_size, sector_size);
+		goto out;
+	}
 
 	sbi->cluster_mask = sbi->cluster_size - 1;
 	sbi->cluster_mask_inv = ~(u64)sbi->cluster_mask;
@@ -794,10 +801,9 @@ static int ntfs_init_from_boot(struct super_block *sb, u32 sector_size,
 				  : (u32)boot->index_size << sbi->cluster_bits;
 
 	sbi->volume.ser_num = le64_to_cpu(boot->serial_num);
-	sbi->volume.size = sectors << sbi->sector_bits;
 
 	/* Warning if RAW volume. */
-	if (dev_size < fs_size) {
+	if (dev_size < sbi->volume.size + boot_sector_size) {
 		u32 mb0, gb0;
 
 		gb0 = format_size_gb(dev_size, &mb0);
-- 
2.33.0