Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
  ceph: select CRYPTO
  ceph: check mapping to determine if FILE_CACHE cap is used
  ceph: only send one flushsnap per cap_snap per mds session
  ceph: fix cap_snap and realm split
  ceph: stop sending FLUSHSNAPs when we hit a dirty capsnap
  ceph: correctly set 'follows' in flushsnap messages
  ceph: fix dn offset during readdir_prepopulate
  ceph: fix file offset wrapping at 4GB on 32-bit archs
  ceph: fix reconnect encoding for old servers
  ceph: fix pagelist kunmap tail
  ceph: fix null pointer deref on anon root dentry release

9 files changed, 84 insertions, 83 deletions

diff --git a/fs/ceph/Kconfig b/fs/ceph/Kconfig
index bc87b9c1d27e..0fcd2640c23f 100644
--- a/fs/ceph/Kconfig
+++ b/fs/ceph/Kconfig
@@ -3,6 +3,7 @@ config CEPH_FS
         depends on INET && EXPERIMENTAL
         select LIBCRC32C
         select CRYPTO_AES
+        select CRYPTO
         help
           Choose Y or M here to include support for mounting the
           experimental Ceph distributed file system.  Ceph is an extremely
diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index 4cfce1ee31fa..efbc604001c8 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -411,8 +411,8 @@ static int writepage_nounlock(struct page *page, struct writeback_control *wbc)
         if (i_size < page_off + len)
                 len = i_size - page_off;
 
-        dout("writepage %p page %p index %lu on %llu~%u\n",
-             inode, page, page->index, page_off, len);
+        dout("writepage %p page %p index %lu on %llu~%u snapc %p\n",
+             inode, page, page->index, page_off, len, snapc);
 
         writeback_stat = atomic_long_inc_return(&client->writeback_count);
         if (writeback_stat >
@@ -766,7 +766,8 @@ get_more_pages:
                         /* ok */
                         if (locked_pages == 0) {
                                 /* prepare async write request */
-                                offset = page->index << PAGE_CACHE_SHIFT;
+                                offset = (unsigned long long)page->index
+                                        << PAGE_CACHE_SHIFT;
                                 len = wsize;
                                 req = ceph_osdc_new_request(&client->osdc,
                                             &ci->i_layout,
diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index a2069b6680ae..73c153092f72 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -814,7 +814,7 @@ int __ceph_caps_used(struct ceph_inode_info *ci)
                 used |= CEPH_CAP_PIN;
         if (ci->i_rd_ref)
                 used |= CEPH_CAP_FILE_RD;
-        if (ci->i_rdcache_ref || ci->i_rdcache_gen)
+        if (ci->i_rdcache_ref || ci->vfs_inode.i_data.nrpages)
                 used |= CEPH_CAP_FILE_CACHE;
         if (ci->i_wr_ref)
                 used |= CEPH_CAP_FILE_WR;
@@ -1195,10 +1195,14 @@ static int __send_cap(struct ceph_mds_client *mdsc, struct ceph_cap *cap,
  * asynchronously back to the MDS once sync writes complete and dirty
  * data is written out.
  *
+ * Unless @again is true, skip cap_snaps that were already sent to
+ * the MDS (i.e., during this session).
+ *
  * Called under i_lock.  Takes s_mutex as needed.
  */
 void __ceph_flush_snaps(struct ceph_inode_info *ci,
-                        struct ceph_mds_session **psession)
+                        struct ceph_mds_session **psession,
+                        int again)
                 __releases(ci->vfs_inode->i_lock)
                 __acquires(ci->vfs_inode->i_lock)
 {
@@ -1227,7 +1231,7 @@ retry:
                  * pages to be written out.
                  */
                 if (capsnap->dirty_pages || capsnap->writing)
-                        continue;
+                        break;
 
                 /*
                  * if cap writeback already occurred, we should have dropped
@@ -1240,6 +1244,13 @@ retry:
                         dout("no auth cap (migrating?), doing nothing\n");
                         goto out;
                 }
+
+                /* only flush each capsnap once */
+                if (!again && !list_empty(&capsnap->flushing_item)) {
+                        dout("already flushed %p, skipping\n", capsnap);
+                        continue;
+                }
+
                 mds = ci->i_auth_cap->session->s_mds;
                 mseq = ci->i_auth_cap->mseq;
 
@@ -1276,8 +1287,8 @@ retry:
                               &session->s_cap_snaps_flushing);
                 spin_unlock(&inode->i_lock);
 
-                dout("flush_snaps %p cap_snap %p follows %lld size %llu\n",
-                     inode, capsnap, next_follows, capsnap->size);
+                dout("flush_snaps %p cap_snap %p follows %lld tid %llu\n",
+                     inode, capsnap, capsnap->follows, capsnap->flush_tid);
                 send_cap_msg(session, ceph_vino(inode).ino, 0,
                              CEPH_CAP_OP_FLUSHSNAP, capsnap->issued, 0,
                              capsnap->dirty, 0, capsnap->flush_tid, 0, mseq,
@@ -1314,7 +1325,7 @@ static void ceph_flush_snaps(struct ceph_inode_info *ci)
         struct inode *inode = &ci->vfs_inode;
 
         spin_lock(&inode->i_lock);
-        __ceph_flush_snaps(ci, NULL);
+        __ceph_flush_snaps(ci, NULL, 0);
         spin_unlock(&inode->i_lock);
 }
 
@@ -1477,7 +1488,7 @@ void ceph_check_caps(struct ceph_inode_info *ci, int flags,
 
         /* flush snaps first time around only */
         if (!list_empty(&ci->i_cap_snaps))
-                __ceph_flush_snaps(ci, &session);
+                __ceph_flush_snaps(ci, &session, 0);
         goto retry_locked;
 retry:
         spin_lock(&inode->i_lock);
@@ -1894,7 +1905,7 @@ static void kick_flushing_capsnaps(struct ceph_mds_client *mdsc,
                 if (cap && cap->session == session) {
                         dout("kick_flushing_caps %p cap %p capsnap %p\n", inode,
                              cap, capsnap);
-                        __ceph_flush_snaps(ci, &session);
+                        __ceph_flush_snaps(ci, &session, 1);
                 } else {
                         pr_err("%p auth cap %p not mds%d ???\n", inode,
                                cap, session->s_mds);
diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index 6e4f43ff23ec..a1986eb52045 100644
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -1021,11 +1021,15 @@ out_touch:
 static void ceph_dentry_release(struct dentry *dentry)
 {
         struct ceph_dentry_info *di = ceph_dentry(dentry);
-        struct inode *parent_inode = dentry->d_parent->d_inode;
-        u64 snapid = ceph_snap(parent_inode);
+        struct inode *parent_inode = NULL;
+        u64 snapid = CEPH_NOSNAP;
 
+        if (!IS_ROOT(dentry)) {
+                parent_inode = dentry->d_parent->d_inode;
+                if (parent_inode)
+                        snapid = ceph_snap(parent_inode);
+        }
         dout("dentry_release %p parent %p\n", dentry, parent_inode);
-
         if (parent_inode && snapid != CEPH_SNAPDIR) {
                 struct ceph_inode_info *ci = ceph_inode(parent_inode);
 
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index e7cca414da03..62377ec37edf 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -845,7 +845,7 @@ static void ceph_set_dentry_offset(struct dentry *dn)
  * the caller) if we fail.
  */
 static struct dentry *splice_dentry(struct dentry *dn, struct inode *in,
-                                    bool *prehash)
+                                    bool *prehash, bool set_offset)
 {
         struct dentry *realdn;
 
@@ -877,7 +877,8 @@ static struct dentry *splice_dentry(struct dentry *dn, struct inode *in,
         }
         if ((!prehash || *prehash) && d_unhashed(dn))
                 d_rehash(dn);
-        ceph_set_dentry_offset(dn);
+        if (set_offset)
+                ceph_set_dentry_offset(dn);
 out:
         return dn;
 }
@@ -1062,7 +1063,7 @@ int ceph_fill_trace(struct super_block *sb, struct ceph_mds_request *req,
                                 d_delete(dn);
                                 goto done;
                         }
-                        dn = splice_dentry(dn, in, &have_lease);
+                        dn = splice_dentry(dn, in, &have_lease, true);
                         if (IS_ERR(dn)) {
                                 err = PTR_ERR(dn);
                                 goto done;
@@ -1105,7 +1106,7 @@ int ceph_fill_trace(struct super_block *sb, struct ceph_mds_request *req,
                         goto done;
                 }
                 dout(" linking snapped dir %p to dn %p\n", in, dn);
-                dn = splice_dentry(dn, in, NULL);
+                dn = splice_dentry(dn, in, NULL, true);
                 if (IS_ERR(dn)) {
                         err = PTR_ERR(dn);
                         goto done;
@@ -1237,7 +1238,7 @@ retry_lookup:
                                 err = PTR_ERR(in);
                                 goto out;
                         }
-                        dn = splice_dentry(dn, in, NULL);
+                        dn = splice_dentry(dn, in, NULL, false);
                         if (IS_ERR(dn))
                                 dn = NULL;
                 }
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index f091b1351786..fad95f8f2608 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -2374,6 +2374,8 @@ static int encode_caps_cb(struct inode *inode, struct ceph_cap *cap,
                                                 num_fcntl_locks,
                                                 num_flock_locks);
                 unlock_kernel();
+        } else {
+                err = ceph_pagelist_append(pagelist, &rec, reclen);
         }
 
 out_free:
diff --git a/fs/ceph/pagelist.c b/fs/ceph/pagelist.c
index b6859f47d364..46a368b6dce5 100644
--- a/fs/ceph/pagelist.c
+++ b/fs/ceph/pagelist.c
@@ -5,10 +5,18 @@
 
 #include "pagelist.h"
 
+static void ceph_pagelist_unmap_tail(struct ceph_pagelist *pl)
+{
+        struct page *page = list_entry(pl->head.prev, struct page,
+                                       lru);
+        kunmap(page);
+}
+
 int ceph_pagelist_release(struct ceph_pagelist *pl)
 {
         if (pl->mapped_tail)
-                kunmap(pl->mapped_tail);
+                ceph_pagelist_unmap_tail(pl);
+
         while (!list_empty(&pl->head)) {
                 struct page *page = list_first_entry(&pl->head, struct page,
                                                      lru);
@@ -26,7 +34,7 @@ static int ceph_pagelist_addpage(struct ceph_pagelist *pl)
         pl->room += PAGE_SIZE;
         list_add_tail(&page->lru, &pl->head);
         if (pl->mapped_tail)
-                kunmap(pl->mapped_tail);
+                ceph_pagelist_unmap_tail(pl);
         pl->mapped_tail = kmap(page);
         return 0;
 }
diff --git a/fs/ceph/snap.c b/fs/ceph/snap.c
index 4868b9dcac5a..190b6c4a6f2b 100644
--- a/fs/ceph/snap.c
+++ b/fs/ceph/snap.c
@@ -119,6 +119,7 @@ static struct ceph_snap_realm *ceph_create_snap_realm(
         INIT_LIST_HEAD(&realm->children);
         INIT_LIST_HEAD(&realm->child_item);
         INIT_LIST_HEAD(&realm->empty_item);
+        INIT_LIST_HEAD(&realm->dirty_item);
         INIT_LIST_HEAD(&realm->inodes_with_caps);
         spin_lock_init(&realm->inodes_with_caps_lock);
         __insert_snap_realm(&mdsc->snap_realms, realm);
@@ -467,7 +468,7 @@ void ceph_queue_cap_snap(struct ceph_inode_info *ci)
                 INIT_LIST_HEAD(&capsnap->ci_item);
                 INIT_LIST_HEAD(&capsnap->flushing_item);
 
-                capsnap->follows = snapc->seq - 1;
+                capsnap->follows = snapc->seq;
                 capsnap->issued = __ceph_caps_issued(ci, NULL);
                 capsnap->dirty = dirty;
 
@@ -604,6 +605,7 @@ int ceph_update_snap_trace(struct ceph_mds_client *mdsc,
         struct ceph_snap_realm *realm;
         int invalidate = 0;
         int err = -ENOMEM;
+        LIST_HEAD(dirty_realms);
 
         dout("update_snap_trace deletion=%d\n", deletion);
 more:
@@ -626,24 +628,6 @@ more:
                 }
         }
 
-        if (le64_to_cpu(ri->seq) > realm->seq) {
-                dout("update_snap_trace updating %llx %p %lld -> %lld\n",
-                     realm->ino, realm, realm->seq, le64_to_cpu(ri->seq));
-                /*
-                 * if the realm seq has changed, queue a cap_snap for every
-                 * inode with open caps.  we do this _before_ we update
-                 * the realm info so that we prepare for writeback under the
-                 * _previous_ snap context.
-                 *
-                 * ...unless it's a snap deletion!
-                 */
-                if (!deletion)
-                        queue_realm_cap_snaps(realm);
-        } else {
-                dout("update_snap_trace %llx %p seq %lld unchanged\n",
-                     realm->ino, realm, realm->seq);
-        }
-
         /* ensure the parent is correct */
         err = adjust_snap_realm_parent(mdsc, realm, le64_to_cpu(ri->parent));
         if (err < 0)
@@ -651,6 +635,8 @@ more:
         invalidate += err;
 
         if (le64_to_cpu(ri->seq) > realm->seq) {
+                dout("update_snap_trace updating %llx %p %lld -> %lld\n",
+                     realm->ino, realm, realm->seq, le64_to_cpu(ri->seq));
                 /* update realm parameters, snap lists */
                 realm->seq = le64_to_cpu(ri->seq);
                 realm->created = le64_to_cpu(ri->created);
@@ -668,9 +654,17 @@ more:
                 if (err < 0)
                         goto fail;
 
+                /* queue realm for cap_snap creation */
+                list_add(&realm->dirty_item, &dirty_realms);
+
                 invalidate = 1;
         } else if (!realm->cached_context) {
+                dout("update_snap_trace %llx %p seq %lld new\n",
+                     realm->ino, realm, realm->seq);
                 invalidate = 1;
+        } else {
+                dout("update_snap_trace %llx %p seq %lld unchanged\n",
+                     realm->ino, realm, realm->seq);
         }
 
         dout("done with %llx %p, invalidated=%d, %p %p\n", realm->ino,
@@ -683,6 +677,14 @@ more:
         if (invalidate)
                 rebuild_snap_realms(realm);
 
+        /*
+         * queue cap snaps _after_ we've built the new snap contexts,
+         * so that i_head_snapc can be set appropriately.
+         */
+        list_for_each_entry(realm, &dirty_realms, dirty_item) {
+                queue_realm_cap_snaps(realm);
+        }
+
         __cleanup_empty_realms(mdsc);
         return 0;
 
@@ -715,7 +717,7 @@ static void flush_snaps(struct ceph_mds_client *mdsc)
                 igrab(inode);
                 spin_unlock(&mdsc->snap_flush_lock);
                 spin_lock(&inode->i_lock);
-                __ceph_flush_snaps(ci, &session);
+                __ceph_flush_snaps(ci, &session, 0);
                 spin_unlock(&inode->i_lock);
                 iput(inode);
                 spin_lock(&mdsc->snap_flush_lock);
@@ -816,6 +818,7 @@ void ceph_handle_snap(struct ceph_mds_client *mdsc,
                         };
                         struct inode *inode = ceph_find_inode(sb, vino);
                         struct ceph_inode_info *ci;
+                        struct ceph_snap_realm *oldrealm;
 
                         if (!inode)
                                 continue;
@@ -841,18 +844,19 @@ void ceph_handle_snap(struct ceph_mds_client *mdsc,
                         dout(" will move %p to split realm %llx %p\n",
                              inode, realm->ino, realm);
                         /*
-                         * Remove the inode from the realm's inode
-                         * list, but don't add it to the new realm
-                         * yet.  We don't want the cap_snap to be
-                         * queued (again) by ceph_update_snap_trace()
-                         * below.  Queue it _now_, under the old context.
+                         * Move the inode to the new realm
                          */
                         spin_lock(&realm->inodes_with_caps_lock);
                         list_del_init(&ci->i_snap_realm_item);
+                        list_add(&ci->i_snap_realm_item,
+                                 &realm->inodes_with_caps);
+                        oldrealm = ci->i_snap_realm;
+                        ci->i_snap_realm = realm;
                         spin_unlock(&realm->inodes_with_caps_lock);
                         spin_unlock(&inode->i_lock);
 
-                        ceph_queue_cap_snap(ci);
+                        ceph_get_snap_realm(mdsc, realm);
+                        ceph_put_snap_realm(mdsc, oldrealm);
 
                         iput(inode);
                         continue;
@@ -880,43 +884,9 @@ skip_inode:
         ceph_update_snap_trace(mdsc, p, e,
                                op == CEPH_SNAP_OP_DESTROY);
 
-        if (op == CEPH_SNAP_OP_SPLIT) {
-                /*
-                 * ok, _now_ add the inodes into the new realm.
-                 */
-                for (i = 0; i < num_split_inos; i++) {
-                        struct ceph_vino vino = {
-                                .ino = le64_to_cpu(split_inos[i]),
-                                .snap = CEPH_NOSNAP,
-                        };
-                        struct inode *inode = ceph_find_inode(sb, vino);
-                        struct ceph_inode_info *ci;
-
-                        if (!inode)
-                                continue;
-                        ci = ceph_inode(inode);
-                        spin_lock(&inode->i_lock);
-                        if (list_empty(&ci->i_snap_realm_item)) {
-                                struct ceph_snap_realm *oldrealm =
-                                        ci->i_snap_realm;
-
-                                dout(" moving %p to split realm %llx %p\n",
-                                     inode, realm->ino, realm);
-                                spin_lock(&realm->inodes_with_caps_lock);
-                                list_add(&ci->i_snap_realm_item,
-                                         &realm->inodes_with_caps);
-                                ci->i_snap_realm = realm;
-                                spin_unlock(&realm->inodes_with_caps_lock);
-                                ceph_get_snap_realm(mdsc, realm);
-                                ceph_put_snap_realm(mdsc, oldrealm);
-                        }
-                        spin_unlock(&inode->i_lock);
-                        iput(inode);
-                }
-
+        if (op == CEPH_SNAP_OP_SPLIT)
                 /* we took a reference when we created the realm, above */
                 ceph_put_snap_realm(mdsc, realm);
-        }
 
         __cleanup_empty_realms(mdsc);
 
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index c33897ae5725..b87638e84c4b 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -690,6 +690,8 @@ struct ceph_snap_realm {
 
         struct list_head empty_item;     /* if i have ref==0 */
 
+        struct list_head dirty_item;     /* if realm needs new context */
+
         /* the current set of snaps for this realm */
         struct ceph_snap_context *cached_context;
 
@@ -826,7 +828,8 @@ extern void ceph_put_cap_refs(struct ceph_inode_info *ci, int had);
 extern void ceph_put_wrbuffer_cap_refs(struct ceph_inode_info *ci, int nr,
                                        struct ceph_snap_context *snapc);
 extern void __ceph_flush_snaps(struct ceph_inode_info *ci,
-                               struct ceph_mds_session **psession);
+                               struct ceph_mds_session **psession,
+                               int again);
 extern void ceph_check_caps(struct ceph_inode_info *ci, int flags,
                             struct ceph_mds_session *session);
 extern void ceph_check_delayed_caps(struct ceph_mds_client *mdsc);