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dracut
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dracut-install.c: try clone ioctl for more speed

master
Harald Hoyer 2012-06-30 09:06:13 +02:00
parent 09eaf9f5b3
commit 85854b245e
1 changed files with 59 additions and 5 deletions
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64
install/dracut-install.c
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@ -39,6 +39,7 @@
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <sys/ioctl.h>

#include "log.h"
#include "hashmap.h"
@ -163,25 +164,78 @@ static int ln_r(const char *src, const char *dst)
return 0;
}

/* Perform the O(1) btrfs clone operation, if possible.
Upon success, return 0. Otherwise, return -1 and set errno. */
static inline int clone_file(int dest_fd, int src_fd)
{
#undef BTRFS_IOCTL_MAGIC
#define BTRFS_IOCTL_MAGIC 0x94
#undef BTRFS_IOC_CLONE
#define BTRFS_IOC_CLONE _IOW (BTRFS_IOCTL_MAGIC, 9, int)
return ioctl(dest_fd, BTRFS_IOC_CLONE, src_fd);
}

static bool use_clone = true;

static int cp(const char *src, const char *dst)
{
int pid;
int status;
int ret;

if(use_clone) {
struct stat sb;
int dest_desc, source_desc;

if (lstat(src, &sb) != 0)
goto normal_copy;

if (S_ISLNK(sb.st_mode))
goto normal_copy;

source_desc = open(src, O_RDONLY | O_CLOEXEC);
if (source_desc < 0)
goto normal_copy;

dest_desc =
open(dst, O_WRONLY | O_CREAT | O_EXCL | O_CLOEXEC,
(sb.st_mode) & (S_ISUID | S_ISGID | S_ISVTX | S_IRWXU | S_IRWXG | S_IRWXO));

if (dest_desc < 0) {
close(source_desc);
goto normal_copy;
}

ret = clone_file(dest_desc, source_desc);
close(source_desc);
if (ret == 0) {
if (fchown(dest_desc, sb.st_uid, sb.st_gid) != 0)
fchown(dest_desc, -1, sb.st_gid);
close(dest_desc);
return ret;
}
close(dest_desc);

/* clone did not work, remove the file */
unlink(dst);
/* do not try clone again */
use_clone = false;
}

normal_copy:
pid = fork();
if (pid == 0) {
execlp("cp", "cp", "--reflink=auto", "--sparse=auto", "--preserve=mode", "-fL", src, dst, NULL);
_exit(EXIT_FAILURE);
}

while (waitpid(pid, &status, 0) < 0) {
while (waitpid(pid, &ret, 0) < 0) {
if (errno != EINTR) {
status = -1;
ret = -1;
break;
}
}

return status;
return ret;
}

static int resolve_deps(const char *src)
@ -643,7 +697,7 @@ static int install_all(int argc, char **argv)
free(dest);
}

if ((ret != 0) && (!arg_optional)) {
if ((ret != 0) && (!arg_optional)) {
log_error("ERROR: installing '%s'", argv[i]);
r = EXIT_FAILURE;
}