io: Remove copy_file_range emulation [BZ #24744]

The kernel is evolving this interface (e.g., removal of the
restriction on cross-device copies), and keeping up with that
is difficult.  Applications which need the function should
run kernels which support the system call instead of relying on
the imperfect glibc emulation.

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>

6 files changed, 5 insertions, 28 deletions

diff --git a/sysdeps/unix/sysv/linux/alpha/kernel-features.h b/sysdeps/unix/sysv/linux/alpha/kernel-features.h
index 4a5d029c1d..81f6c3633a 100644
--- a/sysdeps/unix/sysv/linux/alpha/kernel-features.h
+++ b/sysdeps/unix/sysv/linux/alpha/kernel-features.h
@@ -49,7 +49,6 @@
 /* Support for copy_file_range, statx was added in kernel 4.13.  */
 #if __LINUX_KERNEL_VERSION < 0x040D00
 # undef __ASSUME_MLOCK2
-# undef __ASSUME_COPY_FILE_RANGE
 # undef __ASSUME_STATX
 #endif
 
diff --git a/sysdeps/unix/sysv/linux/arm/kernel-features.h b/sysdeps/unix/sysv/linux/arm/kernel-features.h
index 2d2d355844..4220adff37 100644
--- a/sysdeps/unix/sysv/linux/arm/kernel-features.h
+++ b/sysdeps/unix/sysv/linux/arm/kernel-features.h
@@ -45,7 +45,6 @@
    present in 32-bit kernels from 4.4 and 4.5 respectively.  */
 #if __LINUX_KERNEL_VERSION < 0x040700
 # undef __ASSUME_MLOCK2
-# undef __ASSUME_COPY_FILE_RANGE
 #endif
 
 #undef __ASSUME_CLONE_DEFAULT
diff --git a/sysdeps/unix/sysv/linux/copy_file_range.c b/sysdeps/unix/sysv/linux/copy_file_range.c
index 70961007a5..e950db3bf5 100644
--- a/sysdeps/unix/sysv/linux/copy_file_range.c
+++ b/sysdeps/unix/sysv/linux/copy_file_range.c
@@ -20,27 +20,16 @@
 #include <sysdep-cancel.h>
 #include <unistd.h>
 
-/* Include the fallback implementation.  */
-#ifndef __ASSUME_COPY_FILE_RANGE
-#define COPY_FILE_RANGE_DECL static
-#define COPY_FILE_RANGE copy_file_range_compat
-#include <io/copy_file_range-compat.c>
-#endif
-
 ssize_t
 copy_file_range (int infd, __off64_t *pinoff,
                  int outfd, __off64_t *poutoff,
                  size_t length, unsigned int flags)
 {
 #ifdef __NR_copy_file_range
-  ssize_t ret = SYSCALL_CANCEL (copy_file_range, infd, pinoff, outfd, poutoff,
-                                length, flags);
-# ifndef __ASSUME_COPY_FILE_RANGE
-  if (ret == -1 && errno == ENOSYS)
-    ret = copy_file_range_compat (infd, pinoff, outfd, poutoff, length, flags);
-# endif
-  return ret;
-#else  /* !__NR_copy_file_range */
-  return copy_file_range_compat (infd, pinoff, outfd, poutoff, length, flags);
+  return SYSCALL_CANCEL (copy_file_range, infd, pinoff, outfd, poutoff,
+                         length, flags);
+#else
+  __set_errno (ENOSYS);
+  return -1;
 #endif
 }
diff --git a/sysdeps/unix/sysv/linux/kernel-features.h b/sysdeps/unix/sysv/linux/kernel-features.h
index bc5c959f58..1518bb5228 100644
--- a/sysdeps/unix/sysv/linux/kernel-features.h
+++ b/sysdeps/unix/sysv/linux/kernel-features.h
@@ -100,10 +100,6 @@
 # define __ASSUME_MLOCK2 1
 #endif
 
-#if __LINUX_KERNEL_VERSION >= 0x040500
-# define __ASSUME_COPY_FILE_RANGE 1
-#endif
-
 /* Support for statx was added in kernel 4.11.  */
 #if __LINUX_KERNEL_VERSION >= 0x040B00
 # define __ASSUME_STATX 1
diff --git a/sysdeps/unix/sysv/linux/microblaze/kernel-features.h b/sysdeps/unix/sysv/linux/microblaze/kernel-features.h
index 8df19400af..a787409295 100644
--- a/sysdeps/unix/sysv/linux/microblaze/kernel-features.h
+++ b/sysdeps/unix/sysv/linux/microblaze/kernel-features.h
@@ -60,11 +60,6 @@
 # undef __ASSUME_MLOCK2
 #endif
 
-/* Support for the copy_file_range syscall was added in 4.10.  */
-#if __LINUX_KERNEL_VERSION < 0x040A00
-# undef __ASSUME_COPY_FILE_RANGE
-#endif
-
 /* Support for statx was added in kernel 4.12.  */
 #if __LINUX_KERNEL_VERSION < 0X040C00
 # undef __ASSUME_STATX
diff --git a/sysdeps/unix/sysv/linux/sh/kernel-features.h b/sysdeps/unix/sysv/linux/sh/kernel-features.h
index b11a5cb544..0f287fbf85 100644
--- a/sysdeps/unix/sysv/linux/sh/kernel-features.h
+++ b/sysdeps/unix/sysv/linux/sh/kernel-features.h
@@ -49,7 +49,6 @@
 # undef __ASSUME_RENAMEAT2
 # undef __ASSUME_EXECVEAT
 # undef __ASSUME_MLOCK2
-# undef __ASSUME_COPY_FILE_RANGE
 #endif
 
 /* sh does not support the statx system call before 5.1.  */