From: Sage Weil <sage@redhat.com>
Date: Tue, 24 Sep 2019 19:51:45 +0000 (-0500)
Subject: osd/PrimaryLogPG: impose a per-op return buffer limit (32)
X-Git-Tag: v15.1.0~1384^2~3
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=de1a8eb64122d8541017e73aabf329fc81bc4715;p=ceph.git

osd/PrimaryLogPG: impose a per-op return buffer limit (32)

Limit the return value size for writes, so that we don't inadvertantly
stuff too much data in the PGLog.

Signed-off-by: Sage Weil <sage@redhat.com>
---

diff --git a/src/common/legacy_config_opts.h b/src/common/legacy_config_opts.h
index ddbf75b35c26..e8d122ab01c7 100644
--- a/src/common/legacy_config_opts.h
+++ b/src/common/legacy_config_opts.h
@@ -886,6 +886,7 @@ OPTION(osd_max_attr_size, OPT_U64)
 
 OPTION(osd_max_omap_entries_per_request, OPT_U64)
 OPTION(osd_max_omap_bytes_per_request, OPT_U64)
+OPTION(osd_max_write_op_reply_len, OPT_U64)
 
 OPTION(osd_objectstore, OPT_STR)  // ObjectStore backend type
 OPTION(osd_objectstore_tracing, OPT_BOOL) // true if LTTng-UST tracepoints should be enabled
diff --git a/src/common/options.cc b/src/common/options.cc
index 0ebbe4b3037c..187a5111864f 100644
--- a/src/common/options.cc
+++ b/src/common/options.cc
@@ -4129,6 +4129,11 @@ std::vector<Option> get_global_options() {
     .set_default(1_G)
     .set_description(""),
 
+    Option("osd_max_write_op_reply_len", Option::TYPE_SIZE, Option::LEVEL_ADVANCED)
+    .set_default(32)
+    .set_description("Max size of the per-op payload for requests with the RETURNVEC flag set")
+    .set_long_description("This value caps the amount of data (per op; a request may have many ops) that will be sent back to the client and recorded in the PG log."),
+
     Option("osd_objectstore", Option::TYPE_STR, Option::LEVEL_ADVANCED)
     .set_default("bluestore")
     .set_enum_allowed({"bluestore", "filestore", "memstore", "kstore"})
diff --git a/src/osd/PrimaryLogPG.cc b/src/osd/PrimaryLogPG.cc
index 082adc52159c..d5b4ad26ace3 100644
--- a/src/osd/PrimaryLogPG.cc
+++ b/src/osd/PrimaryLogPG.cc
@@ -3733,7 +3733,14 @@ void PrimaryLogPG::execute_ctx(OpContext *ctx)
     // successful update
     if (ctx->op->allows_returnvec()) {
       // enforce reasonable bound on the return buffer sizes
-#warning write me
+      for (auto& i : *ctx->ops) {
+	if (i.outdata.length() > cct->_conf->osd_max_write_op_reply_len) {
+	  dout(10) << __func__ << " op " << i << " outdata overflow" << dendl;
+	  result = -EOVERFLOW;  // overall result is overflow
+	  i.rval = -EOVERFLOW;
+	  i.outdata.clear();
+	}
+      }
     } else {
       // legacy behavior -- zero result and return data etc.
       ignore_out_data = true;