posixdriver: add provisional manifest

initially, it is just used to remember the multipart layout, but
likely will see other use.

Signed-off-by: Matt Benjamin <mbenjamin@redhat.com>

diff --git a/src/rgw/driver/posix/rgw_sal_posix.cc b/src/rgw/driver/posix/rgw_sal_posix.cc
index 6c6475daaca1c4369a8356868702c67dd3d743e9..461beef033539820fb15b32fac36d200a6f57f21 100644 (file)
--- a/src/rgw/driver/posix/rgw_sal_posix.cc
+++ b/src/rgw/driver/posix/rgw_sal_posix.cc
@@ -35,6 +35,7 @@ const std::string ATTR_PREFIX = "user.X-RGW-";
 #define RGW_POSIX_ATTR_MPUPLOAD "POSIX-Multipart-Upload"
 #define RGW_POSIX_ATTR_OWNER "POSIX-Owner"
 #define RGW_POSIX_ATTR_OBJECT_TYPE "POSIX-Object-Type"
+#define RGW_POSIX_ATTR_MANIFEST "POSIX-Manifest"
 const std::string mp_ns = "multipart";
 const std::string MP_OBJ_PART_PFX = "part-";
 const std::string MP_OBJ_HEAD_NAME = MP_OBJ_PART_PFX + "00000";
@@ -3496,6 +3497,20 @@ int POSIXObject::POSIXReadOp::prepare(optional_yield y, const DoutPrefixProvider
     return -EINVAL;
   }
 
+  buffer::list manifest_bl;
+  if (source->get_attr(RGW_POSIX_ATTR_MANIFEST, manifest_bl)) {
+    POSIXManifest manifest;
+    auto iter = manifest_bl.cbegin();
+    try {
+      manifest.decode(iter);
+      if (manifest.multipart_part_count > 0) {
+        params.parts_count = manifest.multipart_part_count;
+      }
+    } catch (buffer::error& err) {
+      // pass
+    }
+  }
+
 #if 0 // WIP
   if (params.mod_ptr || params.unmod_ptr) {
     obj_time_weight src_weight;
@@ -4047,6 +4062,12 @@ int POSIXMultipartUpload::complete(const DoutPrefixProvider *dpp,
     attrs[RGW_ATTR_COMPRESSION] = tmp;
   }
 
+  POSIXManifest manifest;
+  manifest.multipart_part_count = total_parts;
+  buffer::list manifest_bl;
+  manifest.encode(manifest_bl);
+  attrs[RGW_POSIX_ATTR_MANIFEST] = manifest_bl;
+
   ret = shadow->merge_and_store_attrs(dpp, attrs, y);
   if (ret < 0) {
     return ret;

diff --git a/src/rgw/driver/posix/rgw_sal_posix.h b/src/rgw/driver/posix/rgw_sal_posix.h
index 227d7967c66c5aa49d9ac6fe4c88a7f598ff1d1b..b26a48315091cc654c881ad21b255ad242ed3b6d 100644 (file)
--- a/src/rgw/driver/posix/rgw_sal_posix.h
+++ b/src/rgw/driver/posix/rgw_sal_posix.h
@@ -964,6 +964,23 @@ private:
   int write_attrs(const DoutPrefixProvider *dpp, optional_yield y);
 }; /* POSIXBucket */
 
+struct POSIXManifest {
+  int64_t  multipart_part_count{-1};
+
+  void encode(bufferlist &bl) const {
+    ENCODE_START(1, 1, bl);
+    encode(multipart_part_count, bl);
+    ENCODE_FINISH(bl);
+  }
+
+  void decode(bufferlist::const_iterator &bl) {
+    DECODE_START(1, bl);
+    decode(multipart_part_count, bl);
+    DECODE_FINISH(bl);
+  }
+};
+WRITE_CLASS_ENCODER(POSIXManifest);
+
 class POSIXObject : public StoreObject {
 public:
 private: