ceph: mount non-default filesystem by name
To mount non-default filesytem, user currently needs to provide mds
namespace ID. This is inconvenience.
This patch makes user be able to mount filesystem by name. If user
wants to mount non-default filesystem. Client first subscribes to
fsmap.user. Subscribe to mdsmap.<ID> after getting ID of filesystem.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 78a3495..e555745 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -2166,6 +2166,11 @@
mds = __choose_mds(mdsc, req);
if (mds < 0 ||
ceph_mdsmap_get_state(mdsc->mdsmap, mds) < CEPH_MDS_STATE_ACTIVE) {
+ if (mdsc->mdsmap_err) {
+ err = mdsc->mdsmap_err;
+ dout("do_request mdsmap err %d\n", err);
+ goto finish;
+ }
dout("do_request no mds or not active, waiting for map\n");
list_add(&req->r_wait, &mdsc->waiting_for_map);
goto out;
@@ -3683,11 +3688,86 @@
dout("mdsc_destroy %p done\n", mdsc);
}
+void ceph_mdsc_handle_fsmap(struct ceph_mds_client *mdsc, struct ceph_msg *msg)
+{
+ struct ceph_fs_client *fsc = mdsc->fsc;
+ const char *mds_namespace = fsc->mount_options->mds_namespace;
+ void *p = msg->front.iov_base;
+ void *end = p + msg->front.iov_len;
+ u32 epoch;
+ u32 map_len;
+ u32 num_fs;
+ u32 mount_fscid = (u32)-1;
+ u8 struct_v, struct_cv;
+ int err = -EINVAL;
+
+ ceph_decode_need(&p, end, sizeof(u32), bad);
+ epoch = ceph_decode_32(&p);
+
+ dout("handle_fsmap epoch %u\n", epoch);
+
+ ceph_decode_need(&p, end, 2 + sizeof(u32), bad);
+ struct_v = ceph_decode_8(&p);
+ struct_cv = ceph_decode_8(&p);
+ map_len = ceph_decode_32(&p);
+
+ ceph_decode_need(&p, end, sizeof(u32) * 3, bad);
+ p += sizeof(u32) * 2; /* skip epoch and legacy_client_fscid */
+
+ num_fs = ceph_decode_32(&p);
+ while (num_fs-- > 0) {
+ void *info_p, *info_end;
+ u32 info_len;
+ u8 info_v, info_cv;
+ u32 fscid, namelen;
+
+ ceph_decode_need(&p, end, 2 + sizeof(u32), bad);
+ info_v = ceph_decode_8(&p);
+ info_cv = ceph_decode_8(&p);
+ info_len = ceph_decode_32(&p);
+ ceph_decode_need(&p, end, info_len, bad);
+ info_p = p;
+ info_end = p + info_len;
+ p = info_end;
+
+ ceph_decode_need(&info_p, info_end, sizeof(u32) * 2, bad);
+ fscid = ceph_decode_32(&info_p);
+ namelen = ceph_decode_32(&info_p);
+ ceph_decode_need(&info_p, info_end, namelen, bad);
+
+ if (mds_namespace &&
+ strlen(mds_namespace) == namelen &&
+ !strncmp(mds_namespace, (char *)info_p, namelen)) {
+ mount_fscid = fscid;
+ break;
+ }
+ }
+
+ ceph_monc_got_map(&fsc->client->monc, CEPH_SUB_FSMAP, epoch);
+ if (mount_fscid != (u32)-1) {
+ fsc->client->monc.fs_cluster_id = mount_fscid;
+ ceph_monc_want_map(&fsc->client->monc, CEPH_SUB_MDSMAP,
+ 0, true);
+ ceph_monc_renew_subs(&fsc->client->monc);
+ } else {
+ err = -ENOENT;
+ goto err_out;
+ }
+ return;
+bad:
+ pr_err("error decoding fsmap\n");
+err_out:
+ mutex_lock(&mdsc->mutex);
+ mdsc->mdsmap_err = -ENOENT;
+ __wake_requests(mdsc, &mdsc->waiting_for_map);
+ mutex_unlock(&mdsc->mutex);
+ return;
+}
/*
* handle mds map update.
*/
-void ceph_mdsc_handle_map(struct ceph_mds_client *mdsc, struct ceph_msg *msg)
+void ceph_mdsc_handle_mdsmap(struct ceph_mds_client *mdsc, struct ceph_msg *msg)
{
u32 epoch;
u32 maplen;
@@ -3794,7 +3874,10 @@
switch (type) {
case CEPH_MSG_MDS_MAP:
- ceph_mdsc_handle_map(mdsc, msg);
+ ceph_mdsc_handle_mdsmap(mdsc, msg);
+ break;
+ case CEPH_MSG_FS_MAP_USER:
+ ceph_mdsc_handle_fsmap(mdsc, msg);
break;
case CEPH_MSG_CLIENT_SESSION:
handle_session(s, msg);
diff --git a/fs/ceph/mds_client.h b/fs/ceph/mds_client.h
index 9dd2c82..3c154b8 100644
--- a/fs/ceph/mds_client.h
+++ b/fs/ceph/mds_client.h
@@ -293,6 +293,7 @@
struct completion safe_umount_waiters;
wait_queue_head_t session_close_wq;
struct list_head waiting_for_map;
+ int mdsmap_err;
struct ceph_mds_session **sessions; /* NULL for mds if no session */
atomic_t num_sessions;
@@ -419,8 +420,10 @@
struct dentry *dentry, char action,
u32 seq);
-extern void ceph_mdsc_handle_map(struct ceph_mds_client *mdsc,
- struct ceph_msg *msg);
+extern void ceph_mdsc_handle_mdsmap(struct ceph_mds_client *mdsc,
+ struct ceph_msg *msg);
+extern void ceph_mdsc_handle_fsmap(struct ceph_mds_client *mdsc,
+ struct ceph_msg *msg);
extern struct ceph_mds_session *
ceph_mdsc_open_export_target_session(struct ceph_mds_client *mdsc, int target);
diff --git a/fs/ceph/super.c b/fs/ceph/super.c
index a5b2275..7736a931 100644
--- a/fs/ceph/super.c
+++ b/fs/ceph/super.c
@@ -108,7 +108,6 @@
* mount options
*/
enum {
- Opt_mds_namespace,
Opt_wsize,
Opt_rsize,
Opt_rasize,
@@ -121,6 +120,7 @@
Opt_last_int,
/* int args above */
Opt_snapdirname,
+ Opt_mds_namespace,
Opt_last_string,
/* string args above */
Opt_dirstat,
@@ -144,7 +144,6 @@
};
static match_table_t fsopt_tokens = {
- {Opt_mds_namespace, "mds_namespace=%d"},
{Opt_wsize, "wsize=%d"},
{Opt_rsize, "rsize=%d"},
{Opt_rasize, "rasize=%d"},
@@ -156,6 +155,7 @@
{Opt_congestion_kb, "write_congestion_kb=%d"},
/* int args above */
{Opt_snapdirname, "snapdirname=%s"},
+ {Opt_mds_namespace, "mds_namespace=%s"},
/* string args above */
{Opt_dirstat, "dirstat"},
{Opt_nodirstat, "nodirstat"},
@@ -212,11 +212,14 @@
if (!fsopt->snapdir_name)
return -ENOMEM;
break;
-
- /* misc */
case Opt_mds_namespace:
- fsopt->mds_namespace = intval;
+ fsopt->mds_namespace = kstrndup(argstr[0].from,
+ argstr[0].to-argstr[0].from,
+ GFP_KERNEL);
+ if (!fsopt->mds_namespace)
+ return -ENOMEM;
break;
+ /* misc */
case Opt_wsize:
fsopt->wsize = intval;
break;
@@ -302,6 +305,7 @@
{
dout("destroy_mount_options %p\n", args);
kfree(args->snapdir_name);
+ kfree(args->mds_namespace);
kfree(args->server_path);
kfree(args);
}
@@ -333,6 +337,9 @@
ret = strcmp_null(fsopt1->snapdir_name, fsopt2->snapdir_name);
if (ret)
return ret;
+ ret = strcmp_null(fsopt1->mds_namespace, fsopt2->mds_namespace);
+ if (ret)
+ return ret;
ret = strcmp_null(fsopt1->server_path, fsopt2->server_path);
if (ret)
@@ -376,7 +383,6 @@
fsopt->max_readdir = CEPH_MAX_READDIR_DEFAULT;
fsopt->max_readdir_bytes = CEPH_MAX_READDIR_BYTES_DEFAULT;
fsopt->congestion_kb = default_congestion_kb();
- fsopt->mds_namespace = CEPH_FS_CLUSTER_ID_NONE;
/*
* Distinguish the server list from the path in "dev_name".
@@ -469,8 +475,8 @@
seq_puts(m, ",noacl");
#endif
- if (fsopt->mds_namespace != CEPH_FS_CLUSTER_ID_NONE)
- seq_printf(m, ",mds_namespace=%d", fsopt->mds_namespace);
+ if (fsopt->mds_namespace)
+ seq_printf(m, ",mds_namespace=%s", fsopt->mds_namespace);
if (fsopt->wsize)
seq_printf(m, ",wsize=%d", fsopt->wsize);
if (fsopt->rsize != CEPH_RSIZE_DEFAULT)
@@ -509,9 +515,11 @@
switch (type) {
case CEPH_MSG_MDS_MAP:
- ceph_mdsc_handle_map(fsc->mdsc, msg);
+ ceph_mdsc_handle_mdsmap(fsc->mdsc, msg);
return 0;
-
+ case CEPH_MSG_FS_MAP_USER:
+ ceph_mdsc_handle_fsmap(fsc->mdsc, msg);
+ return 0;
default:
return -1;
}
@@ -543,8 +551,14 @@
goto fail;
}
fsc->client->extra_mon_dispatch = extra_mon_dispatch;
- fsc->client->monc.fs_cluster_id = fsopt->mds_namespace;
- ceph_monc_want_map(&fsc->client->monc, CEPH_SUB_MDSMAP, 0, true);
+
+ if (fsopt->mds_namespace == NULL) {
+ ceph_monc_want_map(&fsc->client->monc, CEPH_SUB_MDSMAP,
+ 0, true);
+ } else {
+ ceph_monc_want_map(&fsc->client->monc, CEPH_SUB_FSMAP,
+ 0, false);
+ }
fsc->mount_options = fsopt;
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 5aa3158..9e82e29 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -62,7 +62,6 @@
int cap_release_safety;
int max_readdir; /* max readdir result (entires) */
int max_readdir_bytes; /* max readdir result (bytes) */
- int mds_namespace;
/*
* everything above this point can be memcmp'd; everything below
@@ -70,6 +69,7 @@
*/
char *snapdir_name; /* default ".snap" */
+ char *mds_namespace; /* default NULL */
char *server_path; /* default "/" */
};