From 6e80f1f615390b2697d27cd2feaf623790d85e29 Mon Sep 17 00:00:00 2001
From: Arvid Norberg <arvid@blockstream.io>
Date: Sun, 19 Aug 2018 21:55:31 +0200
Subject: [PATCH] improve handling of filesystems not supporting fallocate()

---
 ChangeLog              | 1 +
 src/disk_io_thread.cpp | 6 +++++-
 src/file.cpp           | 4 ++--
 src/storage.cpp        | 6 +-----
 4 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index f8fd081b1..1d32f234d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,4 @@
+	* improve handling of filesystems not supporting fallocate()
 	* force-proxy no longer disables DHT
 	* improve connect-boost feature, to make new torrents quickly connect peers
 
diff --git a/src/disk_io_thread.cpp b/src/disk_io_thread.cpp
index 86493ef7c..de7c8b0fd 100644
--- a/src/disk_io_thread.cpp
+++ b/src/disk_io_thread.cpp
@@ -1184,7 +1184,7 @@ namespace libtorrent
 		int ret = j->storage->get_storage_impl()->readv(&b, 1
 			, j->piece, j->d.io.offset, file_flags, j->error);
 
-		TORRENT_ASSERT(ret >= 0 || j->error.ec);
+		TORRENT_ASSERT(ret >= 0 || (j->error.ec && j->error.operation != 0));
 
 		if (!j->error.ec)
 		{
@@ -1258,6 +1258,8 @@ namespace libtorrent
 		ret = j->storage->get_storage_impl()->readv(iov, iov_len
 			, j->piece, adjusted_offset, file_flags, j->error);
 
+		TORRENT_ASSERT(ret >= 0 || (j->error.ec && j->error.operation != 0));
+
 		if (!j->error.ec)
 		{
 			boost::uint32_t const read_time = total_microseconds(clock_type::now() - start_time);
@@ -1418,6 +1420,8 @@ namespace libtorrent
 		int ret = j->storage->get_storage_impl()->writev(&b, 1
 			, j->piece, j->d.io.offset, file_flags, j->error);
 
+		TORRENT_ASSERT(ret >= 0 || (j->error.ec && j->error.operation != 0));
+
 		m_stats_counters.inc_stats_counter(counters::num_writing_threads, -1);
 
 		if (!j->error.ec)
diff --git a/src/file.cpp b/src/file.cpp
index d17a37216..187058779 100644
--- a/src/file.cpp
+++ b/src/file.cpp
@@ -2154,9 +2154,9 @@ typedef struct _FILE_ALLOCATED_RANGE_BUFFER {
 			// if you get a compile error here, you might want to
 			// define TORRENT_HAS_FALLOCATE to 0.
 			ret = posix_fallocate(native_handle(), 0, s);
-			// posix_allocate fails with EINVAL in case the underlying
+			// posix_allocate fails with EINVAL or ENOTSUP in case the underlying
 			// filesystem does not support this operation
-			if (ret != 0 && ret != EINVAL)
+			if (ret != 0 && ret != EINVAL && ret != ENOTSUP)
 			{
 				ec.assign(ret, system_category());
 				return false;
diff --git a/src/storage.cpp b/src/storage.cpp
index d6bf3be13..19108008c 100644
--- a/src/storage.cpp
+++ b/src/storage.cpp
@@ -457,8 +457,6 @@ namespace libtorrent
 				file_handle f = open_file(i, file::read_write, ec);
 				if (ec)
 				{
-					ec.file = i;
-					ec.operation = storage_error::open;
 					prio = m_file_priority;
 					return;
 				}
@@ -489,8 +487,6 @@ namespace libtorrent
 				{
 					if (ec)
 					{
-						ec.file = i;
-						ec.operation = storage_error::open;
 						prio = m_file_priority;
 						return;
 					}
@@ -1600,7 +1596,7 @@ namespace libtorrent
 				{
 					ec.ec = e;
 					ec.file = file;
-					ec.operation = storage_error::fallocate;
+					ec.operation = storage_error::stat;
 					return h;
 				}