ceph: allow connecting to mds whose rank >= mdsmap::m_max_mds

mdsmap::m_max_mds is the expected count of active mds. It's not the
max rank of active mds. User can decrease mdsmap::m_max_mds, but does
not stop mds whose rank >= mdsmap::m_max_mds.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

diff --git a/fs/ceph/debugfs.c b/fs/ceph/debugfs.c
index f2ae393e2c31a2b3dbca7a5f81eeb5b81afa5e1b..4107a887ca34a6de803ba1e3523d332810d629e4 100644 (file)
--- a/fs/ceph/debugfs.c
+++ b/fs/ceph/debugfs.c
@@ -22,20 +22,19 @@ static int mdsmap_show(struct seq_file *s, void *p)
 {
        int i;
        struct ceph_fs_client *fsc = s->private;
+       struct ceph_mdsmap *mdsmap;
 
        if (fsc->mdsc == NULL || fsc->mdsc->mdsmap == NULL)
                return 0;
-       seq_printf(s, "epoch %d\n", fsc->mdsc->mdsmap->m_epoch);
-       seq_printf(s, "root %d\n", fsc->mdsc->mdsmap->m_root);
-       seq_printf(s, "session_timeout %d\n",
-                      fsc->mdsc->mdsmap->m_session_timeout);
-       seq_printf(s, "session_autoclose %d\n",
-                      fsc->mdsc->mdsmap->m_session_autoclose);
-       for (i = 0; i < fsc->mdsc->mdsmap->m_max_mds; i++) {
-               struct ceph_entity_addr *addr =
-                       &fsc->mdsc->mdsmap->m_info[i].addr;
-               int state = fsc->mdsc->mdsmap->m_info[i].state;
-
+       mdsmap = fsc->mdsc->mdsmap;
+       seq_printf(s, "epoch %d\n", mdsmap->m_epoch);
+       seq_printf(s, "root %d\n", mdsmap->m_root);
+       seq_printf(s, "max_mds %d\n", mdsmap->m_max_mds);
+       seq_printf(s, "session_timeout %d\n", mdsmap->m_session_timeout);
+       seq_printf(s, "session_autoclose %d\n", mdsmap->m_session_autoclose);
+       for (i = 0; i < mdsmap->m_num_mds; i++) {
+               struct ceph_entity_addr *addr = &mdsmap->m_info[i].addr;
+               int state = mdsmap->m_info[i].state;
                seq_printf(s, "\tmds%d\t%s\t(%s)\n", i,
                               ceph_pr_addr(&addr->in_addr),
                               ceph_mds_state_name(state));

diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index b16f1cf552a86da2c07251e330ca7bd8eb8f8136..2733932bf192acf233d6e5cdfbadad03ba98e0f3 100644 (file)
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -441,7 +441,7 @@ static struct ceph_mds_session *register_session(struct ceph_mds_client *mdsc,
 {
        struct ceph_mds_session *s;
 
-       if (mds >= mdsc->mdsmap->m_max_mds)
+       if (mds >= mdsc->mdsmap->m_num_mds)
                return ERR_PTR(-EINVAL);
 
        s = kzalloc(sizeof(*s), GFP_NOFS);
@@ -1004,7 +1004,7 @@ static void __open_export_target_sessions(struct ceph_mds_client *mdsc,
        struct ceph_mds_session *ts;
        int i, mds = session->s_mds;
 
-       if (mds >= mdsc->mdsmap->m_max_mds)
+       if (mds >= mdsc->mdsmap->m_num_mds)
                return;
 
        mi = &mdsc->mdsmap->m_info[mds];
@@ -3107,7 +3107,7 @@ static void check_new_map(struct ceph_mds_client *mdsc,
        dout("check_new_map new %u old %u\n",
             newmap->m_epoch, oldmap->m_epoch);
 
-       for (i = 0; i < oldmap->m_max_mds && i < mdsc->max_sessions; i++) {
+       for (i = 0; i < oldmap->m_num_mds && i < mdsc->max_sessions; i++) {
                if (mdsc->sessions[i] == NULL)
                        continue;
                s = mdsc->sessions[i];
@@ -3121,7 +3121,7 @@ static void check_new_map(struct ceph_mds_client *mdsc,
                     ceph_mdsmap_is_laggy(newmap, i) ? " (laggy)" : "",
                     ceph_session_state_name(s->s_state));
 
-               if (i >= newmap->m_max_mds ||
+               if (i >= newmap->m_num_mds ||
                    memcmp(ceph_mdsmap_get_addr(oldmap, i),
                           ceph_mdsmap_get_addr(newmap, i),
                           sizeof(struct ceph_entity_addr))) {
@@ -3167,7 +3167,7 @@ static void check_new_map(struct ceph_mds_client *mdsc,
                }
        }
 
-       for (i = 0; i < newmap->m_max_mds && i < mdsc->max_sessions; i++) {
+       for (i = 0; i < newmap->m_num_mds && i < mdsc->max_sessions; i++) {
                s = mdsc->sessions[i];
                if (!s)
                        continue;

diff --git a/fs/ceph/mdsmap.c b/fs/ceph/mdsmap.c
index 5454e2327a5f77874d63344802709697ceb64de1..1a748cf88535bc80b8060be0cae2d4a92f85599f 100644 (file)
--- a/fs/ceph/mdsmap.c
+++ b/fs/ceph/mdsmap.c
@@ -22,11 +22,11 @@ int ceph_mdsmap_get_random_mds(struct ceph_mdsmap *m)
        int i;
 
        /* special case for one mds */
-       if (1 == m->m_max_mds && m->m_info[0].state > 0)
+       if (1 == m->m_num_mds && m->m_info[0].state > 0)
                return 0;
 
        /* count */
-       for (i = 0; i < m->m_max_mds; i++)
+       for (i = 0; i < m->m_num_mds; i++)
                if (m->m_info[i].state > 0)
                        n++;
        if (n == 0)
@@ -135,8 +135,9 @@ struct ceph_mdsmap *ceph_mdsmap_decode(void **p, void *end)
        m->m_session_autoclose = ceph_decode_32(p);
        m->m_max_file_size = ceph_decode_64(p);
        m->m_max_mds = ceph_decode_32(p);
+       m->m_num_mds = m->m_max_mds;
 
-       m->m_info = kcalloc(m->m_max_mds, sizeof(*m->m_info), GFP_NOFS);
+       m->m_info = kcalloc(m->m_num_mds, sizeof(*m->m_info), GFP_NOFS);
        if (m->m_info == NULL)
                goto nomem;
 
@@ -207,9 +208,20 @@ struct ceph_mdsmap *ceph_mdsmap_decode(void **p, void *end)
                     ceph_pr_addr(&addr.in_addr),
                     ceph_mds_state_name(state));
 
-               if (mds < 0 || mds >= m->m_max_mds || state <= 0)
+               if (mds < 0 || state <= 0)
                        continue;
 
+               if (mds >= m->m_num_mds) {
+                       int new_num = max(mds + 1, m->m_num_mds * 2);
+                       void *new_m_info = krealloc(m->m_info,
+                                               new_num * sizeof(*m->m_info),
+                                               GFP_NOFS | __GFP_ZERO);
+                       if (!new_m_info)
+                               goto nomem;
+                       m->m_info = new_m_info;
+                       m->m_num_mds = new_num;
+               }
+
                info = &m->m_info[mds];
                info->global_id = global_id;
                info->state = state;
@@ -229,6 +241,14 @@ struct ceph_mdsmap *ceph_mdsmap_decode(void **p, void *end)
                        info->export_targets = NULL;
                }
        }
+       if (m->m_num_mds > m->m_max_mds) {
+               /* find max up mds */
+               for (i = m->m_num_mds; i >= m->m_max_mds; i--) {
+                       if (i == 0 || m->m_info[i-1].state > 0)
+                               break;
+               }
+               m->m_num_mds = i;
+       }
 
        /* pg_pools */
        ceph_decode_32_safe(p, end, n, bad);
@@ -270,12 +290,22 @@ struct ceph_mdsmap *ceph_mdsmap_decode(void **p, void *end)
 
                for (i = 0; i < n; i++) {
                        s32 mds = ceph_decode_32(p);
-                       if (mds >= 0 && mds < m->m_max_mds) {
+                       if (mds >= 0 && mds < m->m_num_mds) {
                                if (m->m_info[mds].laggy)
                                        num_laggy++;
                        }
                }
                m->m_num_laggy = num_laggy;
+
+               if (n > m->m_num_mds) {
+                       void *new_m_info = krealloc(m->m_info,
+                                                   n * sizeof(*m->m_info),
+                                                   GFP_NOFS | __GFP_ZERO);
+                       if (!new_m_info)
+                               goto nomem;
+                       m->m_info = new_m_info;
+               }
+               m->m_num_mds = n;
        }
 
        /* inc */
@@ -341,7 +371,7 @@ void ceph_mdsmap_destroy(struct ceph_mdsmap *m)
 {
        int i;
 
-       for (i = 0; i < m->m_max_mds; i++)
+       for (i = 0; i < m->m_num_mds; i++)
                kfree(m->m_info[i].export_targets);
        kfree(m->m_info);
        kfree(m->m_data_pg_pools);
@@ -357,7 +387,7 @@ bool ceph_mdsmap_is_cluster_available(struct ceph_mdsmap *m)
                return false;
        if (m->m_num_laggy > 0)
                return false;
-       for (i = 0; i < m->m_max_mds; i++) {
+       for (i = 0; i < m->m_num_mds; i++) {
                if (m->m_info[i].state == CEPH_MDS_STATE_ACTIVE)
                        nr_active++;
        }

diff --git a/include/linux/ceph/mdsmap.h b/include/linux/ceph/mdsmap.h
index 8ed5dc505fbb2e0672efd81089d1e35caf8e062c..d5f783f3226a8deb43f9336e7fe3c1b955b0e137 100644 (file)
--- a/include/linux/ceph/mdsmap.h
+++ b/include/linux/ceph/mdsmap.h
@@ -25,6 +25,7 @@ struct ceph_mdsmap {
        u32 m_session_autoclose;        /* seconds */
        u64 m_max_file_size;
        u32 m_max_mds;                  /* size of m_addr, m_state arrays */
+       int m_num_mds;
        struct ceph_mds_info *m_info;
 
        /* which object pools file data can be stored in */
@@ -40,7 +41,7 @@ struct ceph_mdsmap {
 static inline struct ceph_entity_addr *
 ceph_mdsmap_get_addr(struct ceph_mdsmap *m, int w)
 {
-       if (w >= m->m_max_mds)
+       if (w >= m->m_num_mds)
                return NULL;
        return &m->m_info[w].addr;
 }
@@ -48,14 +49,14 @@ ceph_mdsmap_get_addr(struct ceph_mdsmap *m, int w)
 static inline int ceph_mdsmap_get_state(struct ceph_mdsmap *m, int w)
 {
        BUG_ON(w < 0);
-       if (w >= m->m_max_mds)
+       if (w >= m->m_num_mds)
                return CEPH_MDS_STATE_DNE;
        return m->m_info[w].state;
 }
 
 static inline bool ceph_mdsmap_is_laggy(struct ceph_mdsmap *m, int w)
 {
-       if (w >= 0 && w < m->m_max_mds)
+       if (w >= 0 && w < m->m_num_mds)
                return m->m_info[w].laggy;
        return false;
 }