LU-8998 lfs: user space tools for PFL

[fs/lustre-release.git] / lustre / include / lustre / lustre_ostid.h

diff --git a/lustre/include/lustre/lustre_ostid.h b/lustre/include/lustre/lustre_ostid.h
index aebb33e..4e1122d 100644 (file)
--- a/lustre/include/lustre/lustre_ostid.h
+++ b/lustre/include/lustre/lustre_ostid.h
@@ -239,4 +239,58 @@ static inline void fid_to_lmm_oi(const struct lu_fid *fid,
        oi->oi.oi_seq = fid_seq(fid);
 }
 
+/**
+ * Unpack an OST object id/seq (group) into a FID.  This is needed for
+ * converting all obdo, lmm, lsm, etc. 64-bit id/seq pairs into proper
+ * FIDs.  Note that if an id/seq is already in FID/IDIF format it will
+ * be passed through unchanged.  Only legacy OST objects in "group 0"
+ * will be mapped into the IDIF namespace so that they can fit into the
+ * struct lu_fid fields without loss.
+ */
+static inline int ostid_to_fid(struct lu_fid *fid, const struct ost_id *ostid,
+                              __u32 ost_idx)
+{
+       __u64 seq = ostid_seq(ostid);
+
+       if (ost_idx > 0xffff) {
+               CERROR("bad ost_idx, "DOSTID" ost_idx:%u\n", POSTID(ostid),
+                      ost_idx);
+               return -EBADF;
+       }
+
+       if (fid_seq_is_mdt0(seq)) {
+               __u64 oid = ostid_id(ostid);
+
+               /* This is a "legacy" (old 1.x/2.early) OST object in "group 0"
+                * that we map into the IDIF namespace.  It allows up to 2^48
+                * objects per OST, as this is the object namespace that has
+                * been in production for years.  This can handle create rates
+                * of 1M objects/s/OST for 9 years, or combinations thereof.
+                */
+               if (oid >= IDIF_MAX_OID) {
+                       CERROR("bad MDT0 id(1), "DOSTID" ost_idx:%u\n",
+                              POSTID(ostid), ost_idx);
+                       return -EBADF;
+               }
+               fid->f_seq = fid_idif_seq(oid, ost_idx);
+               /* truncate to 32 bits by assignment */
+               fid->f_oid = oid;
+               /* in theory, not currently used */
+               fid->f_ver = oid >> 48;
+       } else if (!fid_seq_is_default(seq)) {
+               /* This is either an IDIF object, which identifies objects
+                * across all OSTs, or a regular FID.  The IDIF namespace
+                * maps legacy OST objects into the FID namespace.  In both
+                * cases, we just pass the FID through, no conversion needed.
+                */
+               if (ostid->oi_fid.f_ver) {
+                       CERROR("bad MDT0 id(2), "DOSTID" ost_idx:%u\n",
+                              POSTID(ostid), ost_idx);
+                       return -EBADF;
+               }
+               *fid = ostid->oi_fid;
+       }
+
+       return 0;
+}
 #endif