Merge tag 'ceph-for-6.4-rc1' of https://github.com/ceph/ceph-client

Pull ceph updates from Ilya Dryomov:
 "A few filesystem improvements, with a rather nasty use-after-free fix
  from Xiubo intended for stable"

* tag 'ceph-for-6.4-rc1' of https://github.com/ceph/ceph-client:
  ceph: reorder fields in 'struct ceph_snapid_map'
  ceph: pass ino# instead of old_dentry if it's disconnected
  ceph: fix potential use-after-free bug when trimming caps
  ceph: implement writeback livelock avoidance using page tagging
  ceph: do not print the whole xattr value if it's too long

8 files changed, 102 insertions, 47 deletions

diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index d5335f445233..6bb251a4d613 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -808,6 +808,7 @@ static int ceph_writepages_start(struct address_space *mapping,
 	bool should_loop, range_whole = false;
 	bool done = false;
 	bool caching = ceph_is_cache_enabled(inode);
+	xa_mark_t tag;
 
 	if (wbc->sync_mode == WB_SYNC_NONE &&
 	    fsc->write_congested)
@@ -834,6 +835,11 @@ static int ceph_writepages_start(struct address_space *mapping,
 	start_index = wbc->range_cyclic ? mapping->writeback_index : 0;
 	index = start_index;
 
+	if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages) {
+		tag = PAGECACHE_TAG_TOWRITE;
+	} else {
+		tag = PAGECACHE_TAG_DIRTY;
+	}
 retry:
 	/* find oldest snap context with dirty data */
 	snapc = get_oldest_context(inode, &ceph_wbc, NULL);
@@ -872,6 +878,9 @@ retry:
 		dout(" non-head snapc, range whole\n");
 	}
 
+	if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
+		tag_pages_for_writeback(mapping, index, end);
+
 	ceph_put_snap_context(last_snapc);
 	last_snapc = snapc;
 
@@ -888,7 +897,7 @@ retry:
 
 get_more_pages:
 		nr_folios = filemap_get_folios_tag(mapping, &index,
-				end, PAGECACHE_TAG_DIRTY, &fbatch);
+						   end, tag, &fbatch);
 		dout("pagevec_lookup_range_tag got %d\n", nr_folios);
 		if (!nr_folios && !locked_pages)
 			break;
diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 7cc20772eac9..789be30d6ee2 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -431,7 +431,7 @@ void ceph_reservation_status(struct ceph_fs_client *fsc,
  *
  * Called with i_ceph_lock held.
  */
-static struct ceph_cap *__get_cap_for_mds(struct ceph_inode_info *ci, int mds)
+struct ceph_cap *__get_cap_for_mds(struct ceph_inode_info *ci, int mds)
 {
 	struct ceph_cap *cap;
 	struct rb_node *n = ci->i_caps.rb_node;
diff --git a/fs/ceph/debugfs.c b/fs/ceph/debugfs.c
index bec3c4549c07..3904333fa6c3 100644
--- a/fs/ceph/debugfs.c
+++ b/fs/ceph/debugfs.c
@@ -248,14 +248,20 @@ static int metrics_caps_show(struct seq_file *s, void *p)
 	return 0;
 }
 
-static int caps_show_cb(struct inode *inode, struct ceph_cap *cap, void *p)
+static int caps_show_cb(struct inode *inode, int mds, void *p)
 {
+	struct ceph_inode_info *ci = ceph_inode(inode);
 	struct seq_file *s = p;
-
-	seq_printf(s, "0x%-17llx%-3d%-17s%-17s\n", ceph_ino(inode),
-		   cap->session->s_mds,
-		   ceph_cap_string(cap->issued),
-		   ceph_cap_string(cap->implemented));
+	struct ceph_cap *cap;
+
+	spin_lock(&ci->i_ceph_lock);
+	cap = __get_cap_for_mds(ci, mds);
+	if (cap)
+		seq_printf(s, "0x%-17llx%-3d%-17s%-17s\n", ceph_ino(inode),
+			   cap->session->s_mds,
+			   ceph_cap_string(cap->issued),
+			   ceph_cap_string(cap->implemented));
+	spin_unlock(&ci->i_ceph_lock);
 	return 0;
 }
 
diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index 0ced8b570e42..cb67ac821f0e 100644
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -1050,6 +1050,9 @@ static int ceph_link(struct dentry *old_dentry, struct inode *dir,
 	struct ceph_mds_request *req;
 	int err;
 
+	if (dentry->d_flags & DCACHE_DISCONNECTED)
+		return -EINVAL;
+
 	err = ceph_wait_on_conflict_unlink(dentry);
 	if (err)
 		return err;
@@ -1057,8 +1060,8 @@ static int ceph_link(struct dentry *old_dentry, struct inode *dir,
 	if (ceph_snap(dir) != CEPH_NOSNAP)
 		return -EROFS;
 
-	dout("link in dir %p old_dentry %p dentry %p\n", dir,
-	     old_dentry, dentry);
+	dout("link in dir %p %llx.%llx old_dentry %p:'%pd' dentry %p:'%pd'\n",
+	     dir, ceph_vinop(dir), old_dentry, old_dentry, dentry, dentry);
 	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LINK, USE_AUTH_MDS);
 	if (IS_ERR(req)) {
 		d_drop(dentry);
@@ -1067,6 +1070,12 @@ static int ceph_link(struct dentry *old_dentry, struct inode *dir,
 	req->r_dentry = dget(dentry);
 	req->r_num_caps = 2;
 	req->r_old_dentry = dget(old_dentry);
+	/*
+	 * The old_dentry maybe a DCACHE_DISCONNECTED dentry, then we
+	 * will just pass the ino# to MDSs.
+	 */
+	if (old_dentry->d_flags & DCACHE_DISCONNECTED)
+		req->r_ino2 = ceph_vino(d_inode(old_dentry));
 	req->r_parent = dir;
 	ihold(dir);
 	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 27a245d959c0..29cf00220b09 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -1632,8 +1632,8 @@ static void cleanup_session_requests(struct ceph_mds_client *mdsc,
  * Caller must hold session s_mutex.
  */
 int ceph_iterate_session_caps(struct ceph_mds_session *session,
-			      int (*cb)(struct inode *, struct ceph_cap *,
-					void *), void *arg)
+			      int (*cb)(struct inode *, int mds, void *),
+			      void *arg)
 {
 	struct list_head *p;
 	struct ceph_cap *cap;
@@ -1645,6 +1645,8 @@ int ceph_iterate_session_caps(struct ceph_mds_session *session,
 	spin_lock(&session->s_cap_lock);
 	p = session->s_caps.next;
 	while (p != &session->s_caps) {
+		int mds;
+
 		cap = list_entry(p, struct ceph_cap, session_caps);
 		inode = igrab(&cap->ci->netfs.inode);
 		if (!inode) {
@@ -1652,6 +1654,7 @@ int ceph_iterate_session_caps(struct ceph_mds_session *session,
 			continue;
 		}
 		session->s_cap_iterator = cap;
+		mds = cap->mds;
 		spin_unlock(&session->s_cap_lock);
 
 		if (last_inode) {
@@ -1663,7 +1666,7 @@ int ceph_iterate_session_caps(struct ceph_mds_session *session,
 			old_cap = NULL;
 		}
 
-		ret = cb(inode, cap, arg);
+		ret = cb(inode, mds, arg);
 		last_inode = inode;
 
 		spin_lock(&session->s_cap_lock);
@@ -1696,20 +1699,25 @@ out:
 	return ret;
 }
 
-static int remove_session_caps_cb(struct inode *inode, struct ceph_cap *cap,
-				  void *arg)
+static int remove_session_caps_cb(struct inode *inode, int mds, void *arg)
 {
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	bool invalidate = false;
-	int iputs;
+	struct ceph_cap *cap;
+	int iputs = 0;
 
-	dout("removing cap %p, ci is %p, inode is %p\n",
-	     cap, ci, &ci->netfs.inode);
 	spin_lock(&ci->i_ceph_lock);
-	iputs = ceph_purge_inode_cap(inode, cap, &invalidate);
+	cap = __get_cap_for_mds(ci, mds);
+	if (cap) {
+		dout(" removing cap %p, ci is %p, inode is %p\n",
+		     cap, ci, &ci->netfs.inode);
+
+		iputs = ceph_purge_inode_cap(inode, cap, &invalidate);
+	}
 	spin_unlock(&ci->i_ceph_lock);
 
-	wake_up_all(&ci->i_cap_wq);
+	if (cap)
+		wake_up_all(&ci->i_cap_wq);
 	if (invalidate)
 		ceph_queue_invalidate(inode);
 	while (iputs--)
@@ -1780,8 +1788,7 @@ enum {
  *
  * caller must hold s_mutex.
  */
-static int wake_up_session_cb(struct inode *inode, struct ceph_cap *cap,
-			      void *arg)
+static int wake_up_session_cb(struct inode *inode, int mds, void *arg)
 {
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	unsigned long ev = (unsigned long)arg;
@@ -1792,12 +1799,14 @@ static int wake_up_session_cb(struct inode *inode, struct ceph_cap *cap,
 		ci->i_requested_max_size = 0;
 		spin_unlock(&ci->i_ceph_lock);
 	} else if (ev == RENEWCAPS) {
-		if (cap->cap_gen < atomic_read(&cap->session->s_cap_gen)) {
-			/* mds did not re-issue stale cap */
-			spin_lock(&ci->i_ceph_lock);
+		struct ceph_cap *cap;
+
+		spin_lock(&ci->i_ceph_lock);
+		cap = __get_cap_for_mds(ci, mds);
+		/* mds did not re-issue stale cap */
+		if (cap && cap->cap_gen < atomic_read(&cap->session->s_cap_gen))
 			cap->issued = cap->implemented = CEPH_CAP_PIN;
-			spin_unlock(&ci->i_ceph_lock);
-		}
+		spin_unlock(&ci->i_ceph_lock);
 	} else if (ev == FORCE_RO) {
 	}
 	wake_up_all(&ci->i_cap_wq);
@@ -1959,16 +1968,22 @@ out:
  * Yes, this is a bit sloppy.  Our only real goal here is to respond to
  * memory pressure from the MDS, though, so it needn't be perfect.
  */
-static int trim_caps_cb(struct inode *inode, struct ceph_cap *cap, void *arg)
+static int trim_caps_cb(struct inode *inode, int mds, void *arg)
 {
 	int *remaining = arg;
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	int used, wanted, oissued, mine;
+	struct ceph_cap *cap;
 
 	if (*remaining <= 0)
 		return -1;
 
 	spin_lock(&ci->i_ceph_lock);
+	cap = __get_cap_for_mds(ci, mds);
+	if (!cap) {
+		spin_unlock(&ci->i_ceph_lock);
+		return 0;
+	}
 	mine = cap->issued | cap->implemented;
 	used = __ceph_caps_used(ci);
 	wanted = __ceph_caps_file_wanted(ci);
@@ -2555,6 +2570,7 @@ static struct ceph_msg *create_request_message(struct ceph_mds_session *session,
 	u64 ino1 = 0, ino2 = 0;
 	int pathlen1 = 0, pathlen2 = 0;
 	bool freepath1 = false, freepath2 = false;
+	struct dentry *old_dentry = NULL;
 	int len;
 	u16 releases;
 	void *p, *end;
@@ -2572,7 +2588,10 @@ static struct ceph_msg *create_request_message(struct ceph_mds_session *session,
 	}
 
 	/* If r_old_dentry is set, then assume that its parent is locked */
-	ret = set_request_path_attr(NULL, req->r_old_dentry,
+	if (req->r_old_dentry &&
+	    !(req->r_old_dentry->d_flags & DCACHE_DISCONNECTED))
+		old_dentry = req->r_old_dentry;
+	ret = set_request_path_attr(NULL, old_dentry,
 			      req->r_old_dentry_dir,
 			      req->r_path2, req->r_ino2.ino,
 			      &path2, &pathlen2, &ino2, &freepath2, true);
@@ -3911,26 +3930,22 @@ out_unlock:
 /*
  * Encode information about a cap for a reconnect with the MDS.
  */
-static int reconnect_caps_cb(struct inode *inode, struct ceph_cap *cap,
-			  void *arg)
+static int reconnect_caps_cb(struct inode *inode, int mds, void *arg)
 {
 	union {
 		struct ceph_mds_cap_reconnect v2;
 		struct ceph_mds_cap_reconnect_v1 v1;
 	} rec;
-	struct ceph_inode_info *ci = cap->ci;
+	struct ceph_inode_info *ci = ceph_inode(inode);
 	struct ceph_reconnect_state *recon_state = arg;
 	struct ceph_pagelist *pagelist = recon_state->pagelist;
 	struct dentry *dentry;
+	struct ceph_cap *cap;
 	char *path;
-	int pathlen = 0, err;
+	int pathlen = 0, err = 0;
 	u64 pathbase;
 	u64 snap_follows;
 
-	dout(" adding %p ino %llx.%llx cap %p %lld %s\n",
-	     inode, ceph_vinop(inode), cap, cap->cap_id,
-	     ceph_cap_string(cap->issued));
-
 	dentry = d_find_primary(inode);
 	if (dentry) {
 		/* set pathbase to parent dir when msg_version >= 2 */
@@ -3947,6 +3962,15 @@ static int reconnect_caps_cb(struct inode *inode, struct ceph_cap *cap,
 	}
 
 	spin_lock(&ci->i_ceph_lock);
+	cap = __get_cap_for_mds(ci, mds);
+	if (!cap) {
+		spin_unlock(&ci->i_ceph_lock);
+		goto out_err;
+	}
+	dout(" adding %p ino %llx.%llx cap %p %lld %s\n",
+	     inode, ceph_vinop(inode), cap, cap->cap_id,
+	     ceph_cap_string(cap->issued));
+
 	cap->seq = 0;        /* reset cap seq */
 	cap->issue_seq = 0;  /* and issue_seq */
 	cap->mseq = 0;       /* and migrate_seq */
diff --git a/fs/ceph/mds_client.h b/fs/ceph/mds_client.h
index 0598faa50e2e..724307ff89cd 100644
--- a/fs/ceph/mds_client.h
+++ b/fs/ceph/mds_client.h
@@ -355,8 +355,8 @@ struct ceph_snapid_map {
 	struct rb_node node;
 	struct list_head lru;
 	atomic_t ref;
-	u64 snap;
 	dev_t dev;
+	u64 snap;
 	unsigned long last_used;
 };
 
@@ -541,8 +541,7 @@ extern void ceph_flush_cap_releases(struct ceph_mds_client *mdsc,
 extern void ceph_queue_cap_reclaim_work(struct ceph_mds_client *mdsc);
 extern void ceph_reclaim_caps_nr(struct ceph_mds_client *mdsc, int nr);
 extern int ceph_iterate_session_caps(struct ceph_mds_session *session,
-				     int (*cb)(struct inode *,
-					       struct ceph_cap *, void *),
+				     int (*cb)(struct inode *, int mds, void *),
 				     void *arg);
 extern void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc);
 
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 6ecca2c6d137..d24bf0db5234 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -1192,6 +1192,8 @@ extern void ceph_kick_flushing_caps(struct ceph_mds_client *mdsc,
 				    struct ceph_mds_session *session);
 void ceph_kick_flushing_inode_caps(struct ceph_mds_session *session,
 				   struct ceph_inode_info *ci);
+extern struct ceph_cap *__get_cap_for_mds(struct ceph_inode_info *ci,
+					  int mds);
 extern struct ceph_cap *ceph_get_cap_for_mds(struct ceph_inode_info *ci,
 					     int mds);
 extern void ceph_take_cap_refs(struct ceph_inode_info *ci, int caps,
diff --git a/fs/ceph/xattr.c b/fs/ceph/xattr.c
index 1fe1b62abebd..806183959c47 100644
--- a/fs/ceph/xattr.c
+++ b/fs/ceph/xattr.c
@@ -535,6 +535,8 @@ static struct ceph_vxattr *ceph_match_vxattr(struct inode *inode,
 	return NULL;
 }
 
+#define MAX_XATTR_VAL_PRINT_LEN 256
+
 static int __set_xattr(struct ceph_inode_info *ci,
 			   const char *name, int name_len,
 			   const char *val, int val_len,
@@ -597,7 +599,7 @@ static int __set_xattr(struct ceph_inode_info *ci,
 		xattr->should_free_name = update_xattr;
 
 		ci->i_xattrs.count++;
-		dout("__set_xattr count=%d\n", ci->i_xattrs.count);
+		dout("%s count=%d\n", __func__, ci->i_xattrs.count);
 	} else {
 		kfree(*newxattr);
 		*newxattr = NULL;
@@ -625,11 +627,13 @@ static int __set_xattr(struct ceph_inode_info *ci,
 	if (new) {
 		rb_link_node(&xattr->node, parent, p);
 		rb_insert_color(&xattr->node, &ci->i_xattrs.index);
-		dout("__set_xattr_val p=%p\n", p);
+		dout("%s p=%p\n", __func__, p);
 	}
 
-	dout("__set_xattr_val added %llx.%llx xattr %p %.*s=%.*s\n",
-	     ceph_vinop(&ci->netfs.inode), xattr, name_len, name, val_len, val);
+	dout("%s added %llx.%llx xattr %p %.*s=%.*s%s\n", __func__,
+	     ceph_vinop(&ci->netfs.inode), xattr, name_len, name,
+	     min(val_len, MAX_XATTR_VAL_PRINT_LEN), val,
+	     val_len > MAX_XATTR_VAL_PRINT_LEN ? "..." : "");
 
 	return 0;
 }
@@ -655,13 +659,15 @@ static struct ceph_inode_xattr *__get_xattr(struct ceph_inode_info *ci,
 		else if (c > 0)
 			p = &(*p)->rb_right;
 		else {
-			dout("__get_xattr %s: found %.*s\n", name,
-			     xattr->val_len, xattr->val);
+			int len = min(xattr->val_len, MAX_XATTR_VAL_PRINT_LEN);
+
+			dout("%s %s: found %.*s%s\n", __func__, name, len,
+			     xattr->val, xattr->val_len > len ? "..." : "");
 			return xattr;
 		}
 	}
 
-	dout("__get_xattr %s: not found\n", name);
+	dout("%s %s: not found\n", __func__, name);
 
 	return NULL;
 }