[LU-19004] server_ioctl uses LU_SEQ_RANGE_MDT wrongly

• Type: Bug
• Resolution: Unresolved
• Priority: Minor
• Fix Version/s: Lustre 2.17.0
• Affects Version/s: Lustre 2.17.0
• Labels: easy smatch
• Severity: 3
• Assignee: WC Triage
• Reporter: Oleg Drokin

Description

smatch highlights that lustre/target/tgt_mount.c::server_ioctl() has this code:

               err = obd_get_info(env, lsi->lsi_osd_exp, sizeof(KEY_FID2IDX),
                                  KEY_FID2IDX, &len, &u.fid);
               if (err == 0) {
                       err = -EINVAL;
                       if (u.range.lsr_flags & LU_SEQ_RANGE_MDT)
                               err = u.range.lsr_index;

The problem is 

#define LU_SEQ_RANGE_MDT  0x0

so it never hits (introduced in https://review.whamcloud.com/c/fs/lustre-release/+/56339)

Overall these values are definet as if they are the bits in a bitmask, but are never used as such which makes everything super confusing, so probably ripe for some rework?

#define LU_SEQ_RANGE_MDT        0x0
#define LU_SEQ_RANGE_OST        0x1
#define LU_SEQ_RANGE_ANY        0x3
#define LU_SEQ_RANGE_MASK       0x3

For example:

 static inline unsigned fld_range_type(const struct lu_seq_range *range)
{
        return range->lsr_flags & LU_SEQ_RANGE_MASK;
}

With the saving grace here being that all values are actually then explicitly compared.

 

Issue Links

• is related to: LU-18212 add LL_IOC_FID2MDTIDX ioctl support on server's mount point.
• is related to: LU-2681 need to handle lsr_flags having other flags set