Re: f2fs: introduce f2fs_issue_discard() to clean up

[Dan Carpenter <dan.carpenter@oracle.com>]

Hello Jaegeuk Kim,

The patch 3fa7fb17dc9a: "f2fs: introduce f2fs_issue_discard() to clean
up" from Nov 12, 2013, leads to the following static checker warning:
	"fs/f2fs/segment.c:274 f2fs_issue_discard()
	 warn: should 'blklen << sbi->log_sectors_per_block' be a 64 bit
	 type?"

fs/f2fs/segment.c
   270  static void f2fs_issue_discard(struct f2fs_sb_info *sbi,
   271                                  block_t blkstart, block_t blklen)
   272  {
   273          sector_t sector_addr = blkstart << sbi->log_sectors_per_block;
   274          sector_t sector_len = blklen << sbi->log_sectors_per_block;

block_t is a 32 bit type and sector_t is a 64 bit type.  The upper 32
bits of the sector_t are not used because the shift will wrap.

   275  
   276          blkdev_issue_discard(sbi->sb->s_bdev, sector_addr, sector_len,
   277                                                          GFP_NOFS, 0);
   278          trace_f2fs_issue_discard(sbi->sb, blkstart, blklen);
   279  }

regards,
dan carpenter


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