From 6e08916eb390c8c6d7486098079836e6804e9ab4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E5=A5=8F=E4=B9=8B=E7=AB=A0?= <zouzhizhang@qq.com>
Date: Fri, 25 May 2018 10:47:56 -0700
Subject: [PATCH] Fix Fadvise on closed file when reads use mmap

Summary:
```PosixMmapReadableFile::fd_``` is closed after created, but needs to remain open for the lifetime of `PosixMmapReadableFile` since it is used whenever `InvalidateCache` is called.
Closes https://github.com/facebook/rocksdb/pull/2764

Differential Revision: D8152515

Pulled By: ajkr

fbshipit-source-id: b738a6a55ba4e392f9b0f374ff396a1e61c64f65
---
 env/env_posix.cc | 2 +-
 env/io_posix.cc  | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/env/env_posix.cc b/env/env_posix.cc
index 660b3cf07..e04eb5bf4 100644
--- a/env/env_posix.cc
+++ b/env/env_posix.cc
@@ -241,9 +241,9 @@ class PosixEnv : public Env {
                                                   size, options));
         } else {
           s = IOError("while mmap file for read", fname, errno);
+          close(fd);
         }
       }
-      close(fd);
     } else {
       if (options.use_direct_reads && !options.use_mmap_reads) {
 #ifdef OS_MACOSX
diff --git a/env/io_posix.cc b/env/io_posix.cc
index 0e067b4e8..216fc897e 100644
--- a/env/io_posix.cc
+++ b/env/io_posix.cc
@@ -456,6 +456,7 @@ PosixMmapReadableFile::~PosixMmapReadableFile() {
     fprintf(stdout, "failed to munmap %p length %" ROCKSDB_PRIszt " \n",
             mmapped_region_, length_);
   }
+  close(fd_);
 }
 
 Status PosixMmapReadableFile::Read(uint64_t offset, size_t n, Slice* result,