Re: [PATCH v2] erofs: fix wrong address in erofs_get_block

[Chao Yu]

On 2020/12/8 17:31, Huang Jianan wrote:

iblock indicates the number of i_blkbits-sized blocks rather than
sectors, fix it.

If the data has a disk mapping, map_bh should be used to read the
correct data from the device.

Thanks for the fix, I was misled by sector_t type...

What about avoiding using generic_block_bmap() which uses buffer_head
structure, it limits mapped size to 32-bits:

https://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs.git/commit/?h=dev-test&id=b876f4c94c3d1688edea021d45a528571499e0b9

Thanks,

Fixes: 9da681e017a3 ("staging: erofs: support bmap")
Signed-off-by: Huang Jianan <huangjia...@oppo.com>
Signed-off-by: Guo Weichao <guoweic...@oppo.com>
---
  fs/erofs/data.c | 4 ++--
  1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/erofs/data.c b/fs/erofs/data.c
index 347be146884c..aad3fb68d6c8 100644
--- a/fs/erofs/data.c
+++ b/fs/erofs/data.c
@@ -316,7 +316,7 @@ static int erofs_get_block(struct inode *inode, sector_t 
iblock,
                           struct buffer_head *bh, int create)
  {
        struct erofs_map_blocks map = {
-               .m_la = iblock << 9,
+               .m_la = blknr_to_addr(iblock),
        };
        int err;

@@ -325,7 +325,7 @@ static int erofs_get_block(struct inode *inode, sector_t iblock,

                return err;

if (map.m_flags & EROFS_MAP_MAPPED)

-               bh->b_blocknr = erofs_blknr(map.m_pa);
+               map_bh(bh, inode->i_sb, erofs_blknr(map.m_pa));

return err;

  }