os: if rename system call fails, try ioctl(FICLONE) #41487

codeaholics · 2020-09-18T20:13:19Z

What version of Go are you using (`go version`)?

$ go version
go version go1.15.2 darwin/amd64

Does this issue reproduce with the latest release?

Yes

What operating system and processor architecture are you using (`go env`)?

go env Output

$ go env
GO111MODULE=""
GOARCH="amd64"
GOBIN=""
GOCACHE="/Users/danny/Library/Caches/go-build"
GOENV="/Users/danny/Library/Application Support/go/env"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="darwin"
GOINSECURE=""
GOMODCACHE="/Users/danny/go/pkg/mod"
GONOPROXY=""
GONOSUMDB=""
GOOS="darwin"
GOPATH="/Users/danny/go"
GOPRIVATE=""
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/usr/local/Cellar/go/1.15.2/libexec"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/usr/local/Cellar/go/1.15.2/libexec/pkg/tool/darwin_amd64"
GCCGO="gccgo"
AR="ar"
CC="clang"
CXX="clang++"
CGO_ENABLED="1"
GOMOD="/Users/danny/workspace/media-sort/go.mod"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/36/kj75t85j1m57cg047cr5dh4m0000gn/T/go-build628346493=/tmp/go-build -gno-record-gcc-switches -fno-common"

What did you do?

I am cross-compiling on Mac for Linux

Linux execution env: Linux nas 4.4.190.x86_64.1 #1 SMP Mon Oct 28 01:55:46 UTC 2019 x86_64 GNU/Linux

Build command: GOOS=linux GOARCH=amd64 go build -v

func move(src, dst string) error {
	err := os.Rename(src, dst)
	// cross device move
	if err != nil && strings.Contains(err.Error(), "cross-device") {
		if err := copy(src, dst); err != nil {
			return err
		}
		if err := os.Remove(src); err != nil {
			return err
		}
	}
	return nil
}

What did you expect to see?

os.Rename() to succeed because the source and target are on the same filesystem.

What did you see instead?

os.Rename() returns "invalid cross-device link" and the above code falls back to copy-and-delete. If I do an mv on the command line, it completes immediately - even for multi-gigabyte files.

The text was updated successfully, but these errors were encountered:

ianlancetaylor · 2020-09-18T20:30:57Z

os.Rename is a fairly thin wrapper around syscall.Rename, which just calls the rename system call. If possible, please run the final GNU/Linux executable under strace -f and see what the rename system call returns.

codeaholics · 2020-09-18T20:42:29Z

Thanks for your quick response @ianlancetaylor. To test, I made an empty file, f, in /data/Videos on my NAS, and mv-ed it to /data/Music. Here's the strace:

execve("/bin/mv", ["mv", "f", "/data/Music"], [/* 17 vars */]) = 0
brk(0)                                  = 0x16eb000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fe1406d8000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=28370, ...}) = 0
mmap(NULL, 28370, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7fe1406d1000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libselinux.so.1", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\20c\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0644, st_size=142728, ...}) = 0
mmap(NULL, 2246896, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fe140295000
mprotect(0x7fe1402b6000, 2097152, PROT_NONE) = 0
mmap(0x7fe1404b6000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x21000) = 0x7fe1404b6000
mmap(0x7fe1404b8000, 6384, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7fe1404b8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libacl.so.1", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\200\37\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0644, st_size=35288, ...}) = 0
mmap(NULL, 2130592, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fe14008c000
mprotect(0x7fe140094000, 2093056, PROT_NONE) = 0
mmap(0x7fe140293000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x7000) = 0x7fe140293000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libattr.so.1", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\320\23\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0644, st_size=18640, ...}) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fe1406d0000
mmap(NULL, 2113912, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fe13fe87000
mprotect(0x7fe13fe8b000, 2093056, PROT_NONE) = 0
mmap(0x7fe14008a000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x3000) = 0x7fe14008a000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\34\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1738176, ...}) = 0
mmap(NULL, 3844640, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fe13fadc000
mprotect(0x7fe13fc7d000, 2097152, PROT_NONE) = 0
mmap(0x7fe13fe7d000, 24576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1a1000) = 0x7fe13fe7d000
mmap(0x7fe13fe83000, 14880, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7fe13fe83000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libpcre.so.3", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\20\27\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0644, st_size=448440, ...}) = 0
mmap(NULL, 2543976, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fe13f86e000
mprotect(0x7fe13f8da000, 2097152, PROT_NONE) = 0
mmap(0x7fe13fada000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x6c000) = 0x7fe13fada000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libdl.so.2", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\320\16\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0644, st_size=14664, ...}) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fe1406cf000
mmap(NULL, 2109712, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fe13f66a000
mprotect(0x7fe13f66d000, 2093056, PROT_NONE) = 0
mmap(0x7fe13f86c000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x2000) = 0x7fe13f86c000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libpthread.so.0", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\320n\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=137384, ...}) = 0
mmap(NULL, 2213008, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fe13f44d000
mprotect(0x7fe13f465000, 2093056, PROT_NONE) = 0
mmap(0x7fe13f664000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x17000) = 0x7fe13f664000
mmap(0x7fe13f666000, 13456, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7fe13f666000
close(3)                                = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fe1406ce000
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fe1406cc000
arch_prctl(ARCH_SET_FS, 0x7fe1406cc800) = 0
mprotect(0x7fe13fe7d000, 16384, PROT_READ) = 0
mprotect(0x7fe13f664000, 4096, PROT_READ) = 0
mprotect(0x7fe13f86c000, 4096, PROT_READ) = 0
mprotect(0x7fe13fada000, 4096, PROT_READ) = 0
mprotect(0x7fe14008a000, 4096, PROT_READ) = 0
mprotect(0x7fe140293000, 4096, PROT_READ) = 0
mprotect(0x7fe1404b6000, 4096, PROT_READ) = 0
mprotect(0x61e000, 4096, PROT_READ)     = 0
mprotect(0x7fe1406da000, 4096, PROT_READ) = 0
munmap(0x7fe1406d1000, 28370)           = 0
set_tid_address(0x7fe1406ccad0)         = 23496
set_robust_list(0x7fe1406ccae0, 24)     = 0
rt_sigaction(SIGRTMIN, {0x7fe13f4539b0, [], SA_RESTORER|SA_SIGINFO, 0x7fe13f45c890}, NULL, 8) = 0
rt_sigaction(SIGRT_1, {0x7fe13f453a40, [], SA_RESTORER|SA_RESTART|SA_SIGINFO, 0x7fe13f45c890}, NULL, 8) = 0
rt_sigprocmask(SIG_UNBLOCK, [RTMIN RT_1], NULL, 8) = 0
getrlimit(RLIMIT_STACK, {rlim_cur=8192*1024, rlim_max=RLIM64_INFINITY}) = 0
statfs("/sys/fs/selinux", 0x7ffc57d353f0) = -1 ENOENT (No such file or directory)
statfs("/selinux", {f_type="EXT2_SUPER_MAGIC", f_bsize=4096, f_blocks=965552, f_bfree=722015, f_bavail=665542, f_files=1048576, f_ffree=1032627, f_fsid={-1827525020, -625743731}, f_namelen=255, f_frsize=4096}) = 0
brk(0)                                  = 0x16eb000
brk(0x170c000)                          = 0x170c000
open("/proc/filesystems", O_RDONLY)     = 3
fstat(3, {st_mode=S_IFREG|0444, st_size=0, ...}) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fe1406d7000
read(3, "nodev\tsysfs\nnodev\trootfs\nnodev\tt"..., 1024) = 370
read(3, "", 1024)                       = 0
close(3)                                = 0
munmap(0x7fe1406d7000, 4096)            = 0
open("/usr/lib/locale/locale-archive", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=6839968, ...}) = 0
mmap(NULL, 6839968, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7fe13edc7000
close(3)                                = 0
geteuid()                               = 0
ioctl(0, SNDCTL_TMR_TIMEBASE or SNDRV_TIMER_IOCTL_NEXT_DEVICE or TCGETS, {B38400 opost isig icanon echo ...}) = 0
stat("/data/Music", {st_mode=S_IFDIR|0777, st_size=38, ...}) = 0
lstat("f", {st_mode=S_IFREG|0666, st_size=0, ...}) = 0
lstat("/data/Music/f", 0x7ffc57d35060)  = -1 ENOENT (No such file or directory)
rename("f", "/data/Music/f")            = -1 EXDEV (Invalid cross-device link)
unlink("/data/Music/f")                 = -1 ENOENT (No such file or directory)
open("f", O_RDONLY|O_NOFOLLOW)          = 3
fstat(3, {st_mode=S_IFREG|0666, st_size=0, ...}) = 0
open("/data/Music/f", O_WRONLY|O_CREAT|O_EXCL, 0600) = 4
fstat(4, {st_mode=S_IFREG|0600, st_size=0, ...}) = 0
ioctl(4, BTRFS_IOC_CLONE, 0x3)          = 0
utimensat(4, NULL, {{1600461257, 619450219}, {1600461257, 619450219}}, 0) = 0
flistxattr(3, NULL, 0)                  = 24
flistxattr(3, "system.posix_acl_access\0", 24) = 24
open("/etc/xattr.conf", O_RDONLY)       = -1 ENOENT (No such file or directory)
fgetxattr(3, "system.posix_acl_access", 0x0, 0) = 68
fgetxattr(3, "system.posix_acl_access", "\x02\x00\x00\x00\x01\x00\x06\x00\xff\xff\xff\xff\x02\x00\x07\x00b\x00\x00\x00\x02\x00\x07\x00c\x00\x00\x00\x04\x00\x07\x00\xff\xff\xff\xff\x08\x00\x07\x00b\x00\x00\x00\x08\x00\x07\x00c\x00\x00\x00\x10\x00\x06\x00\xff\xff\xff\xff \x00\x06\x00\xff\xff\xff\xff", 68) = 68
fsetxattr(4, "system.posix_acl_access", "\x02\x00\x00\x00\x01\x00\x06\x00\xff\xff\xff\xff\x02\x00\x07\x00b\x00\x00\x00\x02\x00\x07\x00c\x00\x00\x00\x04\x00\x07\x00\xff\xff\xff\xff\x08\x00\x07\x00b\x00\x00\x00\x08\x00\x07\x00c\x00\x00\x00\x10\x00\x06\x00\xff\xff\xff\xff \x00\x06\x00\xff\xff\xff\xff", 68, 0) = 0
fgetxattr(3, "system.posix_acl_access", "\x02\x00\x00\x00\x01\x00\x06\x00\xff\xff\xff\xff\x02\x00\x07\x00b\x00\x00\x00\x02\x00\x07\x00c\x00\x00\x00\x04\x00\x07\x00\xff\xff\xff\xff\x08\x00\x07\x00b\x00\x00\x00\x08\x00\x07\x00c\x00\x00\x00\x10\x00\x06\x00\xff\xff\xff\xff \x00\x06\x00\xff\xff\xff\xff", 132) = 68
fsetxattr(4, "system.posix_acl_access", "\x02\x00\x00\x00\x01\x00\x06\x00\xff\xff\xff\xff\x02\x00\x07\x00b\x00\x00\x00\x02\x00\x07\x00c\x00\x00\x00\x04\x00\x07\x00\xff\xff\xff\xff\x08\x00\x07\x00b\x00\x00\x00\x08\x00\x07\x00c\x00\x00\x00\x10\x00\x06\x00\xff\xff\xff\xff \x00\x06\x00\xff\xff\xff\xff", 68, 0) = 0
close(4)                                = 0
close(3)                                = 0
lstat("/", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
newfstatat(AT_FDCWD, "f", {st_mode=S_IFREG|0666, st_size=0, ...}, AT_SYMLINK_NOFOLLOW) = 0
unlinkat(AT_FDCWD, "f", 0)              = 0
lseek(0, 0, SEEK_CUR)                   = -1 ESPIPE (Illegal seek)
close(0)                                = 0
close(1)                                = 0
close(2)                                = 0
exit_group(0)                           = ?
+++ exited with 0 +++

I'm waaaay out of my depth here, but I'm guessing these lines are the important ones:

rename("f", "/data/Music/f")            = -1 EXDEV (Invalid cross-device link)
[... followed shortly by ...]
ioctl(4, BTRFS_IOC_CLONE, 0x3)          = 0

It looks like the rename call fails, and mv falls back to using a BTRFS-specific alternative.

ianlancetaylor · 2020-09-18T20:49:18Z

Interesting. I was not aware of that. I'll retitle this issue.

codeaholics · 2020-09-18T21:04:03Z

I've tried to follow the source for mv, and... well... I'm not a C programmer! 🤣 But ultimately, it ends up here: https://github.com/coreutils/coreutils/blob/master/src/copy.c#L405-L418, which, AFAICT, comes from here: https://github.com/coreutils/coreutils/blob/master/src/copy.c#L1459.

Ultimately, it appears to all be controlled by the defaulting of the following two flags in mv.c:
https://github.com/coreutils/coreutils/blob/master/src/mv.c#L113
https://github.com/coreutils/coreutils/blob/master/src/mv.c#L130

codeaholics · 2020-09-18T21:08:01Z

It's interesting that BTRFS reports those two directories as being on different filesystems, but is then happy to do a CoW!

thanm · 2020-09-18T21:16:57Z

Maybe related: https://superuser.com/questions/948808/why-is-moving-files-between-btrfs-subvolumes-an-expensive-operation

ianlancetaylor changed the title ~~os.Rename() returns "invalid cross-device link" even though source and dest are on same device~~ os: Rename returns "invalid cross-device link" even though source and dest are on same device Sep 18, 2020

ianlancetaylor added the NeedsInvestigation Someone must examine and confirm this is a valid issue and not a duplicate of an existing one. label Sep 18, 2020

ianlancetaylor added this to the Backlog milestone Sep 18, 2020

ianlancetaylor added the WaitingForInfo Issue is not actionable because of missing required information, which needs to be provided. label Sep 18, 2020

ianlancetaylor changed the title ~~os: Rename returns "invalid cross-device link" even though source and dest are on same device~~ os: if rename system call fails, try ioctl(FICLONE) Sep 18, 2020

ianlancetaylor added help wanted and removed WaitingForInfo Issue is not actionable because of missing required information, which needs to be provided. labels Sep 18, 2020

ianlancetaylor modified the milestones: Backlog, Unplanned Sep 18, 2020

ianlancetaylor added the OS-Linux label Sep 18, 2020

codeaholics mentioned this issue Sep 22, 2020

Add an 'mv' action which bangs out to '/bin/mv' to avoid bogus 'cross-device' issue jpillora/media-sort#29

Open

jsquyres mentioned this issue Jul 24, 2023

grabit download fails if target directory is a different filesystem than /tmp cisco-open/grabit#3

Closed

2 tasks

uhppoted mentioned this issue Jul 28, 2023

Allow /tmp and /var to be on different partitions - invalid cross-device link uhppoted/uhppoted-httpd#20

Closed

os: if rename system call fails, try ioctl(FICLONE) #41487

os: if rename system call fails, try ioctl(FICLONE) #41487

codeaholics commented Sep 18, 2020

ianlancetaylor commented Sep 18, 2020

codeaholics commented Sep 18, 2020

ianlancetaylor commented Sep 18, 2020

codeaholics commented Sep 18, 2020

codeaholics commented Sep 18, 2020

thanm commented Sep 18, 2020

os: if rename system call fails, try ioctl(FICLONE) #41487

os: if rename system call fails, try ioctl(FICLONE) #41487

Comments

codeaholics commented Sep 18, 2020

What version of Go are you using (go version)?

Does this issue reproduce with the latest release?

What operating system and processor architecture are you using (go env)?

What did you do?

What did you expect to see?

What did you see instead?

ianlancetaylor commented Sep 18, 2020

codeaholics commented Sep 18, 2020

ianlancetaylor commented Sep 18, 2020

codeaholics commented Sep 18, 2020

codeaholics commented Sep 18, 2020

thanm commented Sep 18, 2020

What version of Go are you using (`go version`)?

What operating system and processor architecture are you using (`go env`)?