#include <poll.h>
#include <time.h>
#include <inttypes.h>
+#include <pthread.h>
#include <libcfs/util/ioctl.h>
#include <libcfs/util/param.h>
return llapi_dir_create(name, mode, ¶m);
}
-/*
- * Find the fsname, the full path, and/or an open fd.
- * Either the fsname or path must not be NULL
- */
-int get_root_path(int want, char *fsname, int *outfd, char *path, int index)
+static int get_file_dev(const char *path, dev_t *dev)
+{
+#ifdef HAVE_STATX
+ struct statx stx;
+
+ if (!dev)
+ return -EINVAL;
+ if (statx(AT_FDCWD, path, 0, 0, &stx))
+ return -errno;
+ *dev = makedev(stx.stx_dev_major, stx.stx_dev_minor);
+#else
+ struct stat st;
+
+ if (!dev)
+ return -EINVAL;
+ if (stat(path, &st) != 0)
+ return -errno;
+
+ *dev = st.st_dev;
+#endif
+ return 0;
+}
+
+static int get_root_fd(const char *rootpath, int *outfd)
+{
+ int rc = 0;
+ int fd;
+
+ fd = open(rootpath, O_RDONLY | O_DIRECTORY | O_NONBLOCK);
+ if (fd < 0) {
+ rc = -errno;
+ llapi_error(LLAPI_MSG_ERROR, rc,
+ "cannot open '%s'", rootpath);
+ } else {
+ *outfd = fd;
+ }
+
+ return rc;
+}
+
+static struct {
+ dev_t dev;
+ char fsname[PATH_MAX];
+ char mnt_dir[PATH_MAX];
+} root_cached = { 0 };
+
+static pthread_rwlock_t root_cached_lock = PTHREAD_RWLOCK_INITIALIZER;
+
+static int get_root_path_fast(int want, char *fsname, int *outfd, char *path,
+ dev_t *dev)
+{
+ int rc = -ENODEV;
+ int fsnamelen;
+ int mntlen;
+
+ pthread_rwlock_rdlock(&root_cached_lock);
+ if (root_cached.dev == 0)
+ goto out_unlock;
+
+ fsnamelen = strlen(root_cached.fsname);
+ mntlen = strlen(root_cached.mnt_dir);
+
+ /* Check the fsname for a match, if given */
+ if (!(want & WANT_FSNAME) && fsname &&
+ strlen(fsname) == fsnamelen &&
+ (strncmp(root_cached.fsname, fsname, fsnamelen) == 0)) {
+ rc = 0;
+ /* Check the dev for a match, if given */
+ } else if (!(want & WANT_DEV) && dev && *dev == root_cached.dev) {
+ rc = 0;
+ /* Otherwise find the longest matching path */
+ } else if (path && strlen(path) >= mntlen &&
+ (strncmp(root_cached.mnt_dir, path, mntlen) == 0) &&
+ (strlen(path) == mntlen || path[mntlen] == '/')) {
+ rc = 0;
+ }
+
+ if (rc)
+ goto out_unlock;
+
+ if ((want & WANT_FSNAME) && fsname)
+ strcpy(fsname, root_cached.fsname);
+ if ((want & WANT_PATH) && path)
+ strcpy(path, root_cached.mnt_dir);
+ if ((want & WANT_DEV) && dev)
+ *dev = root_cached.dev;
+ if ((want & WANT_FD) && outfd)
+ rc = get_root_fd(root_cached.mnt_dir, outfd);
+
+out_unlock:
+ pthread_rwlock_unlock(&root_cached_lock);
+ return rc;
+}
+
+static int get_root_path_slow(int want, char *fsname, int *outfd, char *path,
+ int index, dev_t *dev)
{
struct mntent mnt;
- char buf[PATH_MAX], mntdir[PATH_MAX];
+ char buf[PATH_MAX];
char *ptr, *ptr_end;
FILE *fp;
- int idx = 0, mntlen = 0, fd;
+ int idx = -1, mntlen = 0;
int rc = -ENODEV;
- int fsnamelen, mountlen;
+ int fsnamelen = 0;
+ dev_t devmnt = 0;
/* get the mount point */
fp = setmntent(PROC_MOUNTS, "r");
"cannot retrieve filesystem mount point");
return rc;
}
- while (1) {
- if (getmntent_r(fp, &mnt, buf, sizeof(buf)) == NULL)
- break;
+ while (getmntent_r(fp, &mnt, buf, sizeof(buf))) {
if (!llapi_is_lustre_mnt(&mnt))
continue;
- if ((want & WANT_INDEX) && (idx++ != index))
- continue;
-
+ idx++;
mntlen = strlen(mnt.mnt_dir);
ptr = strchr(mnt.mnt_fsname, '/');
while (ptr && *ptr == '/')
while (*ptr_end != '/' && *ptr_end != '\0')
ptr_end++;
- /* Check the fsname for a match, if given */
- mountlen = ptr_end - ptr;
- if (!(want & WANT_FSNAME) && fsname != NULL &&
- (fsnamelen = strlen(fsname)) > 0 &&
- (fsnamelen != mountlen ||
- (strncmp(ptr, fsname, mountlen) != 0)))
+ fsnamelen = ptr_end - ptr;
+
+ /* ignore unaccessible filesystem */
+ if (get_file_dev(mnt.mnt_dir, &devmnt))
continue;
- /* If the path isn't set return the first one we find */
- if (path == NULL || strlen(path) == 0) {
- strncpy(mntdir, mnt.mnt_dir, sizeof(mntdir) - 1);
- mntdir[sizeof(mntdir) - 1] = '\0';
- if ((want & WANT_FSNAME) && fsname != NULL) {
- strncpy(fsname, ptr, mountlen);
- fsname[mountlen] = '\0';
- }
+ if ((want & WANT_INDEX) && idx == index) {
+ rc = 0;
+ break;
+ }
+
+ /* Check the fsname for a match, if given */
+ if (!(want & WANT_FSNAME) && fsname &&
+ strlen(fsname) == fsnamelen &&
+ (strncmp(ptr, fsname, fsnamelen) == 0)) {
+ rc = 0;
+ break;
+ }
+
+ /* Check the dev for a match, if given */
+ if (!(want & WANT_DEV) && dev && *dev == devmnt) {
rc = 0;
break;
+ }
+
/* Otherwise find the longest matching path */
- } else if ((strlen(path) >= mntlen) &&
- (strncmp(mnt.mnt_dir, path, mntlen) == 0)) {
- /* check the path format */
- if (strlen(path) > mntlen && path[mntlen] != '/')
- continue;
- strncpy(mntdir, mnt.mnt_dir, sizeof(mntdir) - 1);
- mntdir[sizeof(mntdir) - 1] = '\0';
- if ((want & WANT_FSNAME) && fsname != NULL) {
- strncpy(fsname, ptr, mountlen);
- fsname[mountlen] = '\0';
- }
+ if (path && strlen(path) >= mntlen &&
+ (strncmp(mnt.mnt_dir, path, mntlen) == 0) &&
+ (strlen(path) == mntlen || path[mntlen] == '/')) {
rc = 0;
break;
}
}
- endmntent(fp);
+
+ if (rc)
+ goto out;
/* Found it */
- if (rc == 0) {
- if ((want & WANT_PATH) && path != NULL) {
- strncpy(path, mntdir, mntlen);
- path[mntlen] = '\0';
- }
- if (want & WANT_FD) {
- fd = open(mntdir, O_RDONLY | O_DIRECTORY | O_NONBLOCK);
- if (fd < 0) {
- rc = -errno;
- llapi_error(LLAPI_MSG_ERROR, rc,
- "cannot open '%s'", mntdir);
+ if (!(want & WANT_INDEX)) {
+ /* Cache the mount point information */
+ pthread_rwlock_wrlock(&root_cached_lock);
- } else {
- *outfd = fd;
- }
- }
- } else if (want & WANT_ERROR)
+ strncpy(root_cached.fsname, ptr, fsnamelen);
+ root_cached.fsname[fsnamelen] = '\0';
+ strncpy(root_cached.mnt_dir, mnt.mnt_dir, mntlen);
+ root_cached.mnt_dir[mntlen] = '\0';
+ root_cached.dev = devmnt;
+
+ pthread_rwlock_unlock(&root_cached_lock);
+ }
+
+ if ((want & WANT_FSNAME) && fsname) {
+ strncpy(fsname, ptr, fsnamelen);
+ fsname[fsnamelen] = '\0';
+ }
+ if ((want & WANT_PATH) && path) {
+ strncpy(path, mnt.mnt_dir, mntlen);
+ path[mntlen] = '\0';
+ }
+ if ((want & WANT_DEV) && dev)
+ *dev = devmnt;
+ if ((want & WANT_FD) && outfd)
+ rc = get_root_fd(mnt.mnt_dir, outfd);
+
+out:
+ endmntent(fp);
+ return rc;
+}
+
+/*
+ * Find the fsname, the full path, and/or an open fd.
+ * Either the fsname or path must not be NULL
+ */
+int get_root_path(int want, char *fsname, int *outfd, char *path, int index,
+ dev_t *dev)
+{
+ int rc = -ENODEV;
+
+ if (!(want & WANT_INDEX))
+ rc = get_root_path_fast(want, fsname, outfd, path, dev);
+ if (rc)
+ rc = get_root_path_slow(want, fsname, outfd, path, index, dev);
+
+ if (!rc || !(want & WANT_ERROR))
+ return rc;
+
+ if (dev || !(want & WANT_DEV))
+ llapi_err_noerrno(LLAPI_MSG_ERROR,
+ "'%u/%u' dev not on a mounted Lustre filesystem",
+ major(*dev), minor(*dev));
+ else
llapi_err_noerrno(LLAPI_MSG_ERROR,
"'%s' not on a mounted Lustre filesystem",
(want & WANT_PATH) ? fsname : path);
if (fsname)
want |= WANT_FSNAME;
- return get_root_path(want, fsname, NULL, mntdir, idx);
+ return get_root_path(want, fsname, NULL, mntdir, idx, NULL);
}
/* Given a path, find the corresponding Lustre fsname */
int llapi_search_fsname(const char *pathname, char *fsname)
{
- char *path;
+ dev_t dev;
int rc;
- path = realpath(pathname, NULL);
- if (path == NULL) {
- char tmp[PATH_MAX - 1];
- char buf[PATH_MAX];
- char *ptr;
+ rc = get_file_dev(pathname, &dev);
+ if (rc) {
+ char tmp[PATH_MAX];
+ char *parent;
+ int len;
+
+ /* file does not exist try the parent */
+ len = readlink(pathname, tmp, PATH_MAX);
+ if (len != -1)
+ tmp[len] = '\0';
+ else
+ strncpy(tmp, pathname, PATH_MAX - 1);
- tmp[0] = '\0';
- buf[0] = '\0';
- if (pathname[0] != '/') {
- /*
- * Need an absolute path, but realpath() only works for
- * pathnames that actually exist. We go through the
- * extra hurdle of dirname(getcwd() + pathname) in
- * case the relative pathname contains ".." in it.
- */
- char realpath[PATH_MAX - 1];
+ parent = dirname(tmp);
+ rc = get_file_dev(parent, &dev);
+ }
- if (getcwd(realpath, sizeof(realpath) - 2) == NULL) {
- rc = -errno;
- llapi_error(LLAPI_MSG_ERROR, rc,
- "cannot get current working directory");
- return rc;
- }
+ if (rc) {
+ llapi_error(LLAPI_MSG_ERROR, rc,
+ "cannot resolve path '%s'", pathname);
+ return rc;
+ }
- rc = snprintf(tmp, sizeof(tmp), "%s/", realpath);
- if (rc >= sizeof(tmp)) {
- rc = -E2BIG;
- llapi_error(LLAPI_MSG_ERROR, rc,
- "invalid parent path '%s'",
- tmp);
- return rc;
- }
- }
+ rc = get_root_path(WANT_FSNAME | WANT_ERROR, fsname, NULL, NULL, -1,
+ &dev);
- rc = snprintf(buf, sizeof(buf), "%s%s", tmp, pathname);
- if (rc >= sizeof(buf)) {
- rc = -E2BIG;
- llapi_error(LLAPI_MSG_ERROR, rc,
- "invalid path '%s'", pathname);
- return rc;
- }
- path = realpath(buf, NULL);
- if (path == NULL) {
- ptr = strrchr(buf, '/');
- if (ptr == NULL) {
- llapi_error(LLAPI_MSG_ERROR |
- LLAPI_MSG_NO_ERRNO, 0,
- "cannot resolve path '%s'",
- buf);
- return -ENOENT;
- }
- *ptr = '\0';
- path = realpath(buf, NULL);
- if (path == NULL) {
- rc = -errno;
- llapi_error(LLAPI_MSG_ERROR, rc,
- "cannot resolve path '%s'",
- pathname);
- return rc;
- }
- }
- }
- rc = get_root_path(WANT_FSNAME | WANT_ERROR, fsname, NULL, path, -1);
- free(path);
return rc;
}
int llapi_search_rootpath(char *pathname, const char *fsname)
{
+ if (!pathname)
+ return -EINVAL;
+
+ /*
+ * pathname can be used as an argument by get_root_path(),
+ * clear it for safety
+ */
+ pathname[0] = 0;
+ return get_root_path(WANT_PATH, (char *)fsname, NULL, pathname, -1,
+ NULL);
+}
+
+int llapi_search_rootpath_by_dev(char *pathname, dev_t dev)
+{
+ if (!pathname)
+ return -EINVAL;
+
/*
* pathname can be used as an argument by get_root_path(),
* clear it for safety
*/
pathname[0] = 0;
- return get_root_path(WANT_PATH, (char *)fsname, NULL, pathname, -1);
+ return get_root_path(WANT_PATH, NULL, NULL, pathname, -1, &dev);
}
/**
git://git.whamcloud.com / fs / lustre-release.git / blobdiff