- struct lu_seq_range *erange;
- struct lu_seq_range *new;
- struct fld_thread_info *info;
- int rc = 0;
- int do_merge=0;
-
- ENTRY;
-
- info = lu_context_key_get(&env->le_ctx, &fld_thread_key);
- cfs_mutex_lock(&fld->lsf_lock);
-
- erange = &info->fti_lrange;
- new = &info->fti_irange;
- *new = *add_range;
-
- /* STEP 1: try to merge with previous range */
- rc = fld_index_lookup(fld, env, new->lsr_start, erange);
- if (!rc) {
- /* in case of range overlap, mdt ID must be same for both ranges */
- if (new->lsr_mdt != erange->lsr_mdt) {
- CERROR("mdt[%x] for given range is different from"
- "existing overlapping range mdt[%x]\n",
- new->lsr_mdt, erange->lsr_mdt);
- rc = -EIO;
- GOTO(out, rc);
- }
-
- if (new->lsr_end < erange->lsr_end)
- GOTO(out, rc);
- do_merge = 1;
-
- } else if (rc == -ENOENT) {
- /* check for merge case: optimizes for single mds lustre.
- * As entry does not exist, returned entry must be left side
- * entry compared to start of new range (ref dio_lookup()).
- * So try to merge from left.
- */
- if (new->lsr_start == erange->lsr_end &&
- new->lsr_mdt == erange->lsr_mdt)
- do_merge = 1;
- } else {
- /* no overlap allowed in fld, so failure in lookup is error */
- GOTO(out, rc);
- }
-
- if (do_merge) {
- /* new range can be combined with existing one.
- * So delete existing range.
- */
-
- rc = fld_index_delete(fld, env, erange, th);
- if (rc == 0) {
- new->lsr_start = min(erange->lsr_start, new->lsr_start);
- new->lsr_end = max(erange->lsr_end, new->lsr_end);
- } else
- GOTO(out, rc);
-
- do_merge = 0;
- }
-
- /* STEP 2: try to merge with next range */
- rc = fld_index_lookup(fld, env, new->lsr_end, erange);
- if (!rc) {
- /* case range overlap: with right side entry. */
- if (new->lsr_mdt == erange->lsr_mdt)
- do_merge = 1;
- } else if (rc == -ENOENT) {
- /* this range is left of new range end point */
- LASSERT(erange->lsr_end <= new->lsr_end);
-
- if (new->lsr_end == erange->lsr_end)
- do_merge = 1;
- if (new->lsr_start <= erange->lsr_start)
- do_merge = 1;
- } else
- GOTO(out, rc);
-
- if (do_merge) {
- if (new->lsr_mdt != erange->lsr_mdt) {
- CERROR("mdt[%x] for given range is different from"
- "existing overlapping range mdt[%x]\n",
- new->lsr_mdt, erange->lsr_mdt);
- rc = -EIO;
- GOTO(out, rc);
- }
-
- /* merge with next range */
- rc = fld_index_delete(fld, env, erange, th);
- if (rc == 0) {
- new->lsr_start = min(erange->lsr_start, new->lsr_start);
- new->lsr_end = max(erange->lsr_end, new->lsr_end);
- } else
- GOTO(out, rc);
- }