Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/tools/perf/util/copyfile.c b/tools/perf/util/copyfile.c
new file mode 100644
index 0000000..47e03de
--- /dev/null
+++ b/tools/perf/util/copyfile.c
@@ -0,0 +1,146 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "util/copyfile.h"
+#include "util/namespaces.h"
+#include <internal/lib.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+static int slow_copyfile(const char *from, const char *to, struct nsinfo *nsi)
+{
+ int err = -1;
+ char *line = NULL;
+ size_t n;
+ FILE *from_fp, *to_fp;
+ struct nscookie nsc;
+
+ nsinfo__mountns_enter(nsi, &nsc);
+ from_fp = fopen(from, "r");
+ nsinfo__mountns_exit(&nsc);
+ if (from_fp == NULL)
+ goto out;
+
+ to_fp = fopen(to, "w");
+ if (to_fp == NULL)
+ goto out_fclose_from;
+
+ while (getline(&line, &n, from_fp) > 0)
+ if (fputs(line, to_fp) == EOF)
+ goto out_fclose_to;
+ err = 0;
+out_fclose_to:
+ fclose(to_fp);
+ free(line);
+out_fclose_from:
+ fclose(from_fp);
+out:
+ return err;
+}
+
+int copyfile_offset(int ifd, loff_t off_in, int ofd, loff_t off_out, u64 size)
+{
+ void *ptr;
+ loff_t pgoff;
+
+ pgoff = off_in & ~(page_size - 1);
+ off_in -= pgoff;
+
+ ptr = mmap(NULL, off_in + size, PROT_READ, MAP_PRIVATE, ifd, pgoff);
+ if (ptr == MAP_FAILED)
+ return -1;
+
+ while (size) {
+ ssize_t ret = pwrite(ofd, ptr + off_in, size, off_out);
+ if (ret < 0 && errno == EINTR)
+ continue;
+ if (ret <= 0)
+ break;
+
+ size -= ret;
+ off_in += ret;
+ off_out += ret;
+ }
+ munmap(ptr, off_in + size);
+
+ return size ? -1 : 0;
+}
+
+static int copyfile_mode_ns(const char *from, const char *to, mode_t mode,
+ struct nsinfo *nsi)
+{
+ int fromfd, tofd;
+ struct stat st;
+ int err;
+ char *tmp = NULL, *ptr = NULL;
+ struct nscookie nsc;
+
+ nsinfo__mountns_enter(nsi, &nsc);
+ err = stat(from, &st);
+ nsinfo__mountns_exit(&nsc);
+ if (err)
+ goto out;
+ err = -1;
+
+ /* extra 'x' at the end is to reserve space for '.' */
+ if (asprintf(&tmp, "%s.XXXXXXx", to) < 0) {
+ tmp = NULL;
+ goto out;
+ }
+ ptr = strrchr(tmp, '/');
+ if (!ptr)
+ goto out;
+ ptr = memmove(ptr + 1, ptr, strlen(ptr) - 1);
+ *ptr = '.';
+
+ tofd = mkstemp(tmp);
+ if (tofd < 0)
+ goto out;
+
+ if (st.st_size == 0) { /* /proc? do it slowly... */
+ err = slow_copyfile(from, tmp, nsi);
+ if (!err && fchmod(tofd, mode))
+ err = -1;
+ goto out_close_to;
+ }
+
+ if (fchmod(tofd, mode))
+ goto out_close_to;
+
+ nsinfo__mountns_enter(nsi, &nsc);
+ fromfd = open(from, O_RDONLY);
+ nsinfo__mountns_exit(&nsc);
+ if (fromfd < 0)
+ goto out_close_to;
+
+ err = copyfile_offset(fromfd, 0, tofd, 0, st.st_size);
+
+ close(fromfd);
+out_close_to:
+ close(tofd);
+ if (!err)
+ err = link(tmp, to);
+ unlink(tmp);
+out:
+ free(tmp);
+ return err;
+}
+
+int copyfile_ns(const char *from, const char *to, struct nsinfo *nsi)
+{
+ return copyfile_mode_ns(from, to, 0755, nsi);
+}
+
+int copyfile_mode(const char *from, const char *to, mode_t mode)
+{
+ return copyfile_mode_ns(from, to, mode, NULL);
+}
+
+int copyfile(const char *from, const char *to)
+{
+ return copyfile_mode(from, to, 0755);
+}