staging: exfat: Clean up return codes - FFS_MEDIAERR

Convert FFS_MEDIAERR to (mostly) -ENOENT and -EIO.  Some additional code surgery
needed to propogate correct error codes upwards.
Signed-off-by: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Link: https://lore.kernel.org/r/20191112021000.42091-3-Valdis.Kletnieks@vt.eduSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/exfat/exfat.h

@@ -210,7 +210,6 @@ static inline u16 get_row_index(u16 i)
 
 /* return values */
 #define FFS_SUCCESS             0
-#define FFS_MEDIAERR            1
 #define FFS_MOUNTED             3
 #define FFS_NOTMOUNTED          4
 #define FFS_ALIGNMENTERR        5

drivers/staging/exfat/exfat_blkdev.c

@@ -40,11 +40,11 @@ int bdev_read(struct super_block *sb, sector_t secno, struct buffer_head **bh,
 	long flags = sbi->debug_flags;
 
 	if (flags & EXFAT_DEBUGFLAGS_ERROR_RW)
-		return FFS_MEDIAERR;
+		return -EIO;
 #endif /* CONFIG_EXFAT_KERNEL_DEBUG */
 
 	if (!p_bd->opened)
-		return FFS_MEDIAERR;
+		return -ENODEV;
 
 	if (*bh)
 		__brelse(*bh);
@@ -62,7 +62,7 @@ int bdev_read(struct super_block *sb, sector_t secno, struct buffer_head **bh,
 	WARN(!p_fs->dev_ejected,
 	     "[EXFAT] No bh, device seems wrong or to be ejected.\n");
 
-	return FFS_MEDIAERR;
+	return -EIO;
 }
 
 int bdev_write(struct super_block *sb, sector_t secno, struct buffer_head *bh,
@@ -77,11 +77,11 @@ int bdev_write(struct super_block *sb, sector_t secno, struct buffer_head *bh,
 	long flags = sbi->debug_flags;
 
 	if (flags & EXFAT_DEBUGFLAGS_ERROR_RW)
-		return FFS_MEDIAERR;
+		return -EIO;
 #endif /* CONFIG_EXFAT_KERNEL_DEBUG */
 
 	if (!p_bd->opened)
-		return FFS_MEDIAERR;
+		return -ENODEV;
 
 	if (secno == bh->b_blocknr) {
 		lock_buffer(bh);
@@ -89,7 +89,7 @@ int bdev_write(struct super_block *sb, sector_t secno, struct buffer_head *bh,
 		mark_buffer_dirty(bh);
 		unlock_buffer(bh);
 		if (sync && (sync_dirty_buffer(bh) != 0))
-			return FFS_MEDIAERR;
+			return -EIO;
 	} else {
 		count = num_secs << p_bd->sector_size_bits;
 
@@ -115,7 +115,7 @@ int bdev_write(struct super_block *sb, sector_t secno, struct buffer_head *bh,
 	WARN(!p_fs->dev_ejected,
 	     "[EXFAT] No bh, device seems wrong or to be ejected.\n");
 
-	return FFS_MEDIAERR;
+	return -EIO;
 }
 
 int bdev_sync(struct super_block *sb)
@@ -126,11 +126,11 @@ int bdev_sync(struct super_block *sb)
 	long flags = sbi->debug_flags;
 
 	if (flags & EXFAT_DEBUGFLAGS_ERROR_RW)
-		return FFS_MEDIAERR;
+		return -EIO;
 #endif /* CONFIG_EXFAT_KERNEL_DEBUG */
 
 	if (!p_bd->opened)
-		return FFS_MEDIAERR;
+		return -ENODEV;
 
 	return sync_blockdev(sb->s_bdev);
 }