From 27d50fa1571e8fb8082f03da56e806ac4a7883ac Mon Sep 17 00:00:00 2001
From: Sage Weil <sage@redhat.com>
Date: Wed, 22 Feb 2017 17:14:58 -0600
Subject: [PATCH] osd/osd_types: drop ScrubMap::object::nlink; drop some decode
 compat cruft

We moved to v7 encoding in ca81563d8d71052a2040eda74e7ac418f1616fc7, which
was pre-jewel, so that's the oldest version we need to decode.

Drop the nlink field, which has not been used in a long time.

Signed-off-by: Sage Weil <sage@redhat.com>
---
 src/osd/PG.cc        | 18 +-----------------
 src/osd/osd_types.cc | 43 +++++++++++++++----------------------------
 src/osd/osd_types.h  |  3 +--
 3 files changed, 17 insertions(+), 47 deletions(-)

diff --git a/src/osd/PG.cc b/src/osd/PG.cc
index acc0884a8d0..a6fde97beb0 100644
--- a/src/osd/PG.cc
+++ b/src/osd/PG.cc
@@ -3959,10 +3959,9 @@ void PG::_scan_snaps(ScrubMap &smap)
     ScrubMap::object &o = i->second;
 
     if (hoid.snap < CEPH_MAXSNAP) {
-      // fake nlinks for old primaries
+      // check and if necessary fix snap_mapper
       bufferlist bl;
       if (o.attrs.find(OI_ATTR) == o.attrs.end()) {
-	o.nlinks = 0;
 	continue;
       }
       bl.push_back(o.attrs[OI_ATTR]);
@@ -3970,21 +3969,8 @@ void PG::_scan_snaps(ScrubMap &smap)
       try {
 	oi.decode(bl);
       } catch(...) {
-	o.nlinks = 0;
 	continue;
       }
-      if (oi.snaps.empty()) {
-	// Just head
-	o.nlinks = 1;
-      } else if (oi.snaps.size() == 1) {
-	// Just head + only snap
-	o.nlinks = 2;
-      } else {
-	// Just head + 1st and last snaps
-	o.nlinks = 3;
-      }
-
-      // check and if necessary fix snap_mapper
       set<snapid_t> oi_snaps(oi.snaps.begin(), oi.snaps.end());
       set<snapid_t> cur_snaps;
       int r = snap_mapper.get_snaps(hoid, &cur_snaps);
@@ -4025,8 +4011,6 @@ void PG::_scan_snaps(ScrubMap &smap)
 	       << dendl;
 	}
       }
-    } else {
-      o.nlinks = 1;
     }
   }
 }
diff --git a/src/osd/osd_types.cc b/src/osd/osd_types.cc
index b17670cb451..5db71951d7b 100644
--- a/src/osd/osd_types.cc
+++ b/src/osd/osd_types.cc
@@ -5571,13 +5571,13 @@ void ScrubMap::generate_test_instances(list<ScrubMap*>& o)
 void ScrubMap::object::encode(bufferlist& bl) const
 {
   bool compat_read_error = read_error || ec_hash_mismatch || ec_size_mismatch;
-  ENCODE_START(8, 2, bl);
+  ENCODE_START(8, 7, bl);
   ::encode(size, bl);
   ::encode(negative, bl);
   ::encode(attrs, bl);
   ::encode(digest, bl);
   ::encode(digest_present, bl);
-  ::encode(nlinks, bl);
+  ::encode((uint32_t)0, bl);  // obsolete nlinks
   ::encode(snapcolls, bl);
   ::encode(omap_digest, bl);
   ::encode(omap_digest_present, bl);
@@ -5591,37 +5591,24 @@ void ScrubMap::object::encode(bufferlist& bl) const
 
 void ScrubMap::object::decode(bufferlist::iterator& bl)
 {
-  DECODE_START_LEGACY_COMPAT_LEN(8, 2, 2, bl);
+  DECODE_START(8, bl);
   ::decode(size, bl);
   bool tmp, compat_read_error = false;
   ::decode(tmp, bl);
   negative = tmp;
   ::decode(attrs, bl);
-  if (struct_v >= 3) {
-    ::decode(digest, bl);
-    ::decode(tmp, bl);
-    digest_present = tmp;
-  }
-  if (struct_v >= 4) {
-    ::decode(nlinks, bl);
-    ::decode(snapcolls, bl);
-  } else {
-    /* Indicates that encoder was not aware of this field since stat must
-     * return nlink >= 1 */
-    nlinks = 0;
-  }
-  if (struct_v >= 5) {
-    ::decode(omap_digest, bl);
-    ::decode(tmp, bl);
-    omap_digest_present = tmp;
-  }
-  if (struct_v >= 6) {
-    ::decode(compat_read_error, bl);
-  }
-  if (struct_v >= 7) {
-    ::decode(tmp, bl);
-    stat_error = tmp;
-  }
+  ::decode(digest, bl);
+  ::decode(tmp, bl);
+  digest_present = tmp;
+  uint32_t nlinks;
+  ::decode(nlinks, bl);
+  ::decode(snapcolls, bl);
+  ::decode(omap_digest, bl);
+  ::decode(tmp, bl);
+  omap_digest_present = tmp;
+  ::decode(compat_read_error, bl);
+  ::decode(tmp, bl);
+  stat_error = tmp;
   if (struct_v >= 8) {
     ::decode(tmp, bl);
     read_error = tmp;
diff --git a/src/osd/osd_types.h b/src/osd/osd_types.h
index 8d4209a4042..205ad8abfe6 100644
--- a/src/osd/osd_types.h
+++ b/src/osd/osd_types.h
@@ -4657,7 +4657,6 @@ struct ScrubMap {
     uint64_t size;
     __u32 omap_digest;         ///< omap crc32c
     __u32 digest;              ///< data crc32c
-    uint32_t nlinks;
     bool negative:1;
     bool digest_present:1;
     bool omap_digest_present:1;
@@ -4668,7 +4667,7 @@ struct ScrubMap {
 
     object() :
       // Init invalid size so it won't match if we get a stat EIO error
-      size(-1), omap_digest(0), digest(0), nlinks(0), 
+      size(-1), omap_digest(0), digest(0),
       negative(false), digest_present(false), omap_digest_present(false), 
       read_error(false), stat_error(false), ec_hash_mismatch(false), ec_size_mismatch(false) {}
 
-- 
2.39.5