}
/*
- * Attempt an NFSv2/3 mount via a mount(2) system call.
+ * Distinguish between permanent and temporary errors.
+ *
+ * Returns 0 if the passed-in error is temporary, thus the
+ * mount system call should be retried; returns one if the
+ * passed-in error is permanent, thus the mount system call
+ * should not be retried.
+ */
+static int is_permanent_error(int error)
+{
+ switch (error) {
+ case EACCES:
+ case ESTALE:
+ case ETIMEDOUT:
+ case ECONNREFUSED:
+ return 0; /* temporary */
+ default:
+ return 1; /* permanent */
+ }
+}
+
+/*
+ * Reconstruct the mount option string based on a portmapper probe
+ * of the server. Returns one if the server's portmapper returned
+ * something we can use, otherwise zero.
+ *
+ * To handle version and transport protocol fallback properly, we
+ * need to parse some of the mount options in order to set up a
+ * portmap probe. Mount options that rewrite_mount_options()
+ * doesn't recognize are left alone.
+ *
+ * Returns a new group of mount options if successful; otherwise
+ * NULL is returned if some failure occurred.
+ */
+static struct mount_options *rewrite_mount_options(char *str)
+{
+ struct mount_options *options;
+ char *option, new_option[64];
+ clnt_addr_t mnt_server = { };
+ clnt_addr_t nfs_server = { };
+ int p;
+
+ options = po_split(str);
+ if (!options)
+ return NULL;
+
+ option = po_get(options, "addr");
+ if (option) {
+ nfs_server.saddr.sin_family = AF_INET;
+ if (!inet_aton((const char *)option, &nfs_server.saddr.sin_addr))
+ goto err;
+ } else
+ goto err;
+
+ option = po_get(options, "mountaddr");
+ if (option) {
+ mnt_server.saddr.sin_family = AF_INET;
+ if (!inet_aton((const char *)option, &mnt_server.saddr.sin_addr))
+ goto err;
+ } else
+ memcpy(&mnt_server.saddr, &nfs_server.saddr,
+ sizeof(mnt_server.saddr));
+
+ option = po_get(options, "mountport");
+ if (option)
+ mnt_server.pmap.pm_port = atoi(option);
+ mnt_server.pmap.pm_prog = MOUNTPROG;
+ option = po_get(options, "mountvers");
+ if (option)
+ mnt_server.pmap.pm_vers = atoi(option);
+
+ option = po_get(options, "port");
+ if (option) {
+ nfs_server.pmap.pm_port = atoi(option);
+ po_remove_all(options, "port");
+ }
+ nfs_server.pmap.pm_prog = NFS_PROGRAM;
+
+ option = po_get(options, "nfsvers");
+ if (option) {
+ nfs_server.pmap.pm_vers = atoi(option);
+ po_remove_all(options, "nfsvers");
+ }
+ option = po_get(options, "vers");
+ if (option) {
+ nfs_server.pmap.pm_vers = atoi(option);
+ po_remove_all(options, "vers");
+ }
+ option = po_get(options, "proto");
+ if (option) {
+ if (strcmp(option, "tcp") == 0) {
+ nfs_server.pmap.pm_prot = IPPROTO_TCP;
+ po_remove_all(options, "proto");
+ }
+ if (strcmp(option, "udp") == 0) {
+ nfs_server.pmap.pm_prot = IPPROTO_UDP;
+ po_remove_all(options, "proto");
+ }
+ }
+ p = po_rightmost(options, "tcp", "udp");
+ switch (p) {
+ case PO_KEY2_RIGHTMOST:
+ nfs_server.pmap.pm_prot = IPPROTO_UDP;
+ break;
+ case PO_KEY1_RIGHTMOST:
+ nfs_server.pmap.pm_prot = IPPROTO_TCP;
+ break;
+ }
+ po_remove_all(options, "tcp");
+ po_remove_all(options, "udp");
+
+ if (!probe_bothports(&mnt_server, &nfs_server)) {
+ rpc_mount_errors("rpcbind", 0, 0);
+ goto err;
+ }
+
+ snprintf(new_option, sizeof(new_option) - 1,
+ "nfsvers=%lu", nfs_server.pmap.pm_vers);
+ if (po_append(options, new_option) == PO_FAILED)
+ goto err;
+
+ if (nfs_server.pmap.pm_prot == IPPROTO_TCP)
+ snprintf(new_option, sizeof(new_option) - 1,
+ "proto=tcp");
+ else
+ snprintf(new_option, sizeof(new_option) - 1,
+ "proto=udp");
+ if (po_append(options, new_option) == PO_FAILED)
+ goto err;
+
+ if (nfs_server.pmap.pm_port != NFS_PORT) {
+ snprintf(new_option, sizeof(new_option) - 1,
+ "port=%lu", nfs_server.pmap.pm_port);
+ if (po_append(options, new_option) == PO_FAILED)
+ goto err;
+
+ }
+
+ return options;
+
+err:
+ po_destroy(options);
+ return NULL;
+}
+
+/*
+ * Retry an NFS mount that failed because the requested service isn't
+ * available on the server.
*
* Returns 1 if successful. Otherwise, returns zero.
* "errno" is set to reflect the individual error.
+ *
+ * Side effect: If the retry is successful, both 'options' and
+ * 'extra_opts' are updated to reflect the mount options that worked.
+ * If the retry fails, 'options' and 'extra_opts' are left unchanged.
+ */
+static int retry_nfsmount(const char *spec, const char *node,
+ int flags, struct mount_options *options,
+ int fake, char **extra_opts)
+{
+ struct mount_options *retry_options;
+ char *retry_str = NULL;
+
+ retry_options = rewrite_mount_options(*extra_opts);
+ if (!retry_options) {
+ errno = EIO;
+ return 0;
+ }
+
+ if (po_join(retry_options, &retry_str) == PO_FAILED) {
+ po_destroy(retry_options);
+ errno = EIO;
+ return 0;
+ }
+
+ if (verbose)
+ printf(_("%s: text-based options (retry): '%s'\n"),
+ progname, retry_str);
+
+ if (!mount(spec, node, "nfs",
+ flags & ~(MS_USER|MS_USERS), retry_str)) {
+ free(*extra_opts);
+ *extra_opts = retry_str;
+ po_replace(options, retry_options);
+ return 1;
+ }
+
+ po_destroy(retry_options);
+ free(retry_str);
+ return 0;
+}
+
+/*
+ * Attempt an NFSv2/3 mount via a mount(2) system call. If the kernel
+ * claims the requested service isn't supported on the server, probe
+ * the server to see what's supported, rewrite the mount options,
+ * and retry the request.
+ *
+ * Returns 1 if successful. Otherwise, returns zero.
+ * "errno" is set to reflect the individual error.
+ *
+ * Side effect: If the retry is successful, both 'options' and
+ * 'extra_opts' are updated to reflect the mount options that worked.
+ * If the retry fails, 'options' and 'extra_opts' are left unchanged.
*/
static int try_nfs23mount(const char *spec, const char *node,
int flags, struct mount_options *options,
if (!mount(spec, node, "nfs",
flags & ~(MS_USER|MS_USERS), *extra_opts))
return 1;
- return 0;
+
+ /*
+ * The kernel returns EOPNOTSUPP if the RPC bind failed,
+ * and EPROTONOSUPPORT if the version isn't supported.
+ */
+ if (errno != EOPNOTSUPP && errno != EPROTONOSUPPORT)
+ return 0;
+
+ return retry_nfsmount(spec, node, flags, options, fake, extra_opts);
}
/*
options, fake, extra_opts);
}
+/*
+ * Handle "foreground" NFS mounts.
+ *
+ * Retry the mount request for as long as the 'retry=' option says.
+ *
+ * Returns a valid mount command exit code.
+ */
+static int nfsmount_fg(const char *spec, const char *node,
+ const char *type, int flags,
+ struct mount_options *options, int fake,
+ char **extra_opts)
+{
+ unsigned int secs = 1;
+ time_t timeout = time(NULL);
+ char *retry;
+
+ timeout += 60 * 2; /* default: 2 minutes */
+ retry = po_get(options, "retry");
+ if (retry)
+ timeout += 60 * atoi(retry);
+
+ if (verbose)
+ printf(_("%s: timeout set for %s"),
+ progname, ctime(&timeout));
+
+ for (;;) {
+ if (try_mount(spec, node, type, flags,
+ options, fake, extra_opts))
+ return EX_SUCCESS;
+
+ if (is_permanent_error(errno))
+ break;
+
+ if (time(NULL) > timeout) {
+ errno = ETIMEDOUT;
+ break;
+ }
+
+ if (errno != ETIMEDOUT) {
+ if (sleep(secs))
+ break;
+ secs <<= 1;
+ if (secs > 10)
+ secs = 10;
+ }
+ };
+
+ mount_error(spec, node, errno);
+ return EX_FAIL;
+}
+
+/*
+ * Handle "background" NFS mount [first try]
+ *
+ * Returns a valid mount command exit code.
+ *
+ * EX_BG should cause the caller to fork and invoke nfsmount_child.
+ */
+static int nfsmount_parent(const char *spec, const char *node,
+ const char *type, char *hostname, int flags,
+ struct mount_options *options,
+ int fake, char **extra_opts)
+{
+ if (try_mount(spec, node, type, flags, options,
+ fake, extra_opts))
+ return EX_SUCCESS;
+
+ if (is_permanent_error(errno)) {
+ mount_error(spec, node, errno);
+ return EX_FAIL;
+ }
+
+ sys_mount_errors(hostname, errno, 1, 1);
+ return EX_BG;
+}
+
+/*
+ * Handle "background" NFS mount [retry daemon]
+ *
+ * Returns a valid mount command exit code: EX_SUCCESS if successful,
+ * EX_FAIL if a failure occurred. There's nothing to catch the
+ * error return, though, so we use sys_mount_errors to log the
+ * failure.
+ */
+static int nfsmount_child(const char *spec, const char *node,
+ const char *type, char *hostname, int flags,
+ struct mount_options *options,
+ int fake, char **extra_opts)
+{
+ unsigned int secs = 1;
+ time_t timeout = time(NULL);
+ char *retry;
+
+ timeout += 60 * 10000; /* default: 10,000 minutes */
+ retry = po_get(options, "retry");
+ if (retry)
+ timeout += 60 * atoi(retry);
+
+ for (;;) {
+ if (sleep(secs))
+ break;
+ secs <<= 1;
+ if (secs > 120)
+ secs = 120;
+
+ if (try_mount(spec, node, type, flags, options,
+ fake, extra_opts))
+ return EX_SUCCESS;
+
+ if (is_permanent_error(errno))
+ break;
+
+ if (time(NULL) > timeout)
+ break;
+
+ sys_mount_errors(hostname, errno, 1, 1);
+ };
+
+ sys_mount_errors(hostname, errno, 1, 0);
+ return EX_FAIL;
+}
+
+/*
+ * Handle "background" NFS mount
+ *
+ * Returns a valid mount command exit code.
+ */
+static int nfsmount_bg(const char *spec, const char *node,
+ const char *type, char *hostname, int flags,
+ struct mount_options *options,
+ int fake, int child, char **extra_opts)
+{
+ if (!child)
+ return nfsmount_parent(spec, node, type, hostname, flags,
+ options, fake, extra_opts);
+ else
+ return nfsmount_child(spec, node, type, hostname, flags,
+ options, fake, extra_opts);
+}
+
/**
* nfsmount_string - Mount an NFS file system using C string options
* @spec: C string specifying remote share to mount ("hostname:path")
struct mount_options *options = NULL;
struct sockaddr_in saddr;
char *hostname;
- int err, retval = EX_FAIL;
+ int retval = EX_FAIL;
if (!parse_devname(spec, &hostname))
- goto out;
- err = fill_ipv4_sockaddr(hostname, &saddr);
- free(hostname);
- if (!err)
- goto out;
+ return retval;
+ if (!fill_ipv4_sockaddr(hostname, &saddr))
+ goto fail;
options = po_split(*extra_opts);
if (!options) {
nfs_error(_("%s: internal option parsing error"), progname);
- goto out;
+ goto fail;
}
if (!set_mandatory_options(type, &saddr, options))
goto out;
- if (po_join(options, extra_opts) == PO_FAILED) {
- nfs_error(_("%s: internal option parsing error"), progname);
- goto out;
- }
-
- if (verbose)
- printf(_("%s: text-based options: '%s'\n"),
- progname, *extra_opts);
-
- if (!fake) {
- if (mount(spec, node, type,
- flags & ~(MS_USER|MS_USERS), *extra_opts)) {
- mount_error(spec, node, errno);
- goto out;
- }
- }
-
- retval = EX_SUCCESS;
+ if (po_rightmost(options, "bg", "fg") == PO_KEY1_RIGHTMOST)
+ retval = nfsmount_bg(spec, node, type, hostname, flags,
+ options, fake, child, extra_opts);
+ else
+ retval = nfsmount_fg(spec, node, type, flags, options,
+ fake, extra_opts);
out:
po_destroy(options);
+fail:
+ free(hostname);
return retval;
}
projects / nfs-utils.git / blobdiff