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Update to go1.24.0

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This commit is contained in:
Vorapol Rinsatitnon
2025-02-14 12:42:07 +07:00
parent 25e497e367
commit bf266cebe6
3169 changed files with 236789 additions and 60275 deletions
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152
src/internal/poll/copy_file_range_linux.go
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@@ -10,6 +10,10 @@ import (
"syscall"
)
func supportCopyFileRange() bool {
return isKernelVersionGE53()
}
var isKernelVersionGE53 = sync.OnceValue(func() bool {
major, minor := unix.KernelVersion()
// copy_file_range(2) is broken in various ways on kernels older than 5.3,
@@ -18,104 +22,62 @@ var isKernelVersionGE53 = sync.OnceValue(func() bool {
return major > 5 || (major == 5 && minor >= 3)
})
const maxCopyFileRangeRound = 1 << 30
// For best performance, call copy_file_range() with the largest len value
// possible. Linux sets up a limitation of data transfer for most of its I/O
// system calls, as MAX_RW_COUNT (INT_MAX & PAGE_MASK). This value equals to
// the maximum integer value minus a page size that is typically 2^12=4096 bytes.
// That is to say, it's the maximum integer value with the lowest 12 bits unset,
// which is 0x7ffff000.
const maxCopyFileRangeRound = 0x7ffff000
// CopyFileRange copies at most remain bytes of data from src to dst, using
// the copy_file_range system call. dst and src must refer to regular files.
func CopyFileRange(dst, src *FD, remain int64) (written int64, handled bool, err error) {
if !isKernelVersionGE53() {
return 0, false, nil
}
for remain > 0 {
max := remain
if max > maxCopyFileRangeRound {
max = maxCopyFileRangeRound
}
n, err := copyFileRange(dst, src, int(max))
switch err {
case syscall.ENOSYS:
// copy_file_range(2) was introduced in Linux 4.5.
// Go supports Linux >= 2.6.33, so the system call
// may not be present.
//
// If we see ENOSYS, we have certainly not transferred
// any data, so we can tell the caller that we
// couldn't handle the transfer and let them fall
// back to more generic code.
return 0, false, nil
case syscall.EXDEV, syscall.EINVAL, syscall.EIO, syscall.EOPNOTSUPP, syscall.EPERM:
// Prior to Linux 5.3, it was not possible to
// copy_file_range across file systems. Similarly to
// the ENOSYS case above, if we see EXDEV, we have
// not transferred any data, and we can let the caller
// fall back to generic code.
//
// As for EINVAL, that is what we see if, for example,
// dst or src refer to a pipe rather than a regular
// file. This is another case where no data has been
// transferred, so we consider it unhandled.
//
// If src and dst are on CIFS, we can see EIO.
// See issue #42334.
//
// If the file is on NFS, we can see EOPNOTSUPP.
// See issue #40731.
//
// If the process is running inside a Docker container,
// we might see EPERM instead of ENOSYS. See issue
// #40893. Since EPERM might also be a legitimate error,
// don't mark copy_file_range(2) as unsupported.
return 0, false, nil
case nil:
if n == 0 {
// 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
func handleCopyFileRangeErr(err error, copied, written int64) (bool, error) {
switch err {
case syscall.ENOSYS:
// copy_file_range(2) was introduced in Linux 4.5.
// Go supports Linux >= 3.2, so the system call
// may not be present.
//
// If we see ENOSYS, we have certainly not transferred
// any data, so we can tell the caller that we
// couldn't handle the transfer and let them fall
// back to more generic code.
return false, nil
case syscall.EXDEV, syscall.EINVAL, syscall.EIO, syscall.EOPNOTSUPP, syscall.EPERM:
// Prior to Linux 5.3, it was not possible to
// copy_file_range across file systems. Similarly to
// the ENOSYS case above, if we see EXDEV, we have
// not transferred any data, and we can let the caller
// fall back to generic code.
//
// As for EINVAL, that is what we see if, for example,
// dst or src refer to a pipe rather than a regular
// file. This is another case where no data has been
// transferred, so we consider it unhandled.
//
// If src and dst are on CIFS, we can see EIO.
// See issue #42334.
//
// If the file is on NFS, we can see EOPNOTSUPP.
// See issue #40731.
//
// If the process is running inside a Docker container,
// we might see EPERM instead of ENOSYS. See issue
// #40893. Since EPERM might also be a legitimate error,
// don't mark copy_file_range(2) as unsupported.
return false, nil
case nil:
if copied == 0 {
// 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 false, nil
}
remain -= n
written += n
default:
return written, true, err
}
}
return written, true, nil
}
// copyFileRange performs one round of copy_file_range(2).
func copyFileRange(dst, src *FD, max int) (written int64, err error) {
// The signature of copy_file_range(2) is:
//
// ssize_t copy_file_range(int fd_in, loff_t *off_in,
// int fd_out, loff_t *off_out,
// size_t len, unsigned int flags);
//
// Note that in the call to unix.CopyFileRange below, we use nil
// values for off_in and off_out. For the system call, this means
// "use and update the file offsets". That is why we must acquire
// locks for both file descriptors (and why this whole machinery is
// in the internal/poll package to begin with).
if err := dst.writeLock(); err != nil {
return 0, err
}
defer dst.writeUnlock()
if err := src.readLock(); err != nil {
return 0, err
}
defer src.readUnlock()
var n int
for {
n, err = unix.CopyFileRange(src.Sysfd, nil, dst.Sysfd, nil, max, 0)
if err != syscall.EINTR {
break
// Otherwise src is at EOF, which means
// we are done.
}
}
return int64(n), err
return true, err
}