[dev.regabi] all: merge master (5faf941) into dev.regabi

Merge List:

+ 2021-02-16 5faf941df0 internal/goversion: update Version to 1.17
+ 2021-02-16 6f3da9d2f6 README: pull gopher image from website
+ 2021-02-16 098504c73f cmd/link: generate trampoline for inter-dependent packages
+ 2021-02-16 1004a7cb31 runtime/metrics: update documentation to current interface
+ 2021-02-16 6530f2617f doc/go1.16: remove draft notice
+ 2021-02-16 353e111455 doc/go1.16: fix mismatched id attribute
+ 2021-02-16 f0d23c9dbb internal/poll: netpollcheckerr before sendfile
+ 2021-02-16 0cb3415154 doc: remove all docs not tied to distribution
+ 2021-02-16 626ef08127 doc: remove install.html and install-source.html
+ 2021-02-16 30641e36aa internal/poll: if copy_file_range returns 0, assume it failed
+ 2021-02-15 33d72fd412 doc/faq: update generics entry to reflect accepted proposal
+ 2021-02-15 852ce7c212 cmd/go: provide a more helpful suggestion for "go vet -?"
+ 2021-02-13 66c27093d0 cmd/link: fix typo in link_test.go

Change-Id: I98f047b79b93c5ceb344dd43408bcb919b23aeb3

5 files changed, 20 insertions, 2 deletions

diff --git a/src/internal/goversion/goversion.go b/src/internal/goversion/goversion.go
index 513be456bd..4cc15688c0 100644
--- a/src/internal/goversion/goversion.go
+++ b/src/internal/goversion/goversion.go
@@ -9,4 +9,4 @@ package goversion
 //
 // It should be updated at the start of each development cycle to be
 // the version of the next Go 1.x release. See golang.org/issue/40705.
-const Version = 16
+const Version = 17
diff --git a/src/internal/poll/copy_file_range_linux.go b/src/internal/poll/copy_file_range_linux.go
index fc34aef4cb..01b242a4ea 100644
--- a/src/internal/poll/copy_file_range_linux.go
+++ b/src/internal/poll/copy_file_range_linux.go
@@ -112,7 +112,15 @@ func CopyFileRange(dst, src *FD, remain int64) (written int64, handled bool, err
 			return 0, false, nil
 		case nil:
 			if n == 0 {
-				// src is at EOF, which means we are done.
+				// If we did not read any bytes at all,
+				// then this file may be in a file system
+				// where copy_file_range silently fails.
+				// https://lore.kernel.org/linux-fsdevel/20210126233840.GG4626@dread.disaster.area/T/#m05753578c7f7882f6e9ffe01f981bc223edef2b0
+				if written == 0 {
+					return 0, false, nil
+				}
+				// Otherwise src is at EOF, which means
+				// we are done.
 				return written, true, nil
 			}
 			remain -= n
diff --git a/src/internal/poll/sendfile_bsd.go b/src/internal/poll/sendfile_bsd.go
index a24e41dcaa..66005a9f5c 100644
--- a/src/internal/poll/sendfile_bsd.go
+++ b/src/internal/poll/sendfile_bsd.go
@@ -18,6 +18,10 @@ func SendFile(dstFD *FD, src int, pos, remain int64) (int64, error) {
 		return 0, err
 	}
 	defer dstFD.writeUnlock()
+	if err := dstFD.pd.prepareWrite(dstFD.isFile); err != nil {
+		return 0, err
+	}
+
 	dst := int(dstFD.Sysfd)
 	var written int64
 	var err error
diff --git a/src/internal/poll/sendfile_linux.go b/src/internal/poll/sendfile_linux.go
index d64283007d..d6442e8666 100644
--- a/src/internal/poll/sendfile_linux.go
+++ b/src/internal/poll/sendfile_linux.go
@@ -16,6 +16,9 @@ func SendFile(dstFD *FD, src int, remain int64) (int64, error) {
 		return 0, err
 	}
 	defer dstFD.writeUnlock()
+	if err := dstFD.pd.prepareWrite(dstFD.isFile); err != nil {
+		return 0, err
+	}
 
 	dst := int(dstFD.Sysfd)
 	var written int64
diff --git a/src/internal/poll/sendfile_solaris.go b/src/internal/poll/sendfile_solaris.go
index 762992e9eb..748c85131e 100644
--- a/src/internal/poll/sendfile_solaris.go
+++ b/src/internal/poll/sendfile_solaris.go
@@ -20,6 +20,9 @@ func SendFile(dstFD *FD, src int, pos, remain int64) (int64, error) {
 		return 0, err
 	}
 	defer dstFD.writeUnlock()
+	if err := dstFD.pd.prepareWrite(dstFD.isFile); err != nil {
+		return 0, err
+	}
 
 	dst := int(dstFD.Sysfd)
 	var written int64