Commit 44c99757 authored by Yan, Zheng's avatar Yan, Zheng Committed by Sage Weil
Browse files

ceph: set caps count after composing cap reconnect message 



It's possible that some caps get released while composing the cap
reconnect message.

Signed-off-by: default avatarYan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: default avatarSage Weil <sage@inktank.com>
parent a096b09a

fs/ceph/mds_client.c

+18 −5
Original line number Diff line number Diff line
@@ -43,6 +43,7 @@ 
 */



struct ceph_reconnect_state {

	int nr_caps;

	struct ceph_pagelist *pagelist;

	bool flock;

};
@@ -2549,6 +2550,8 @@ static int encode_caps_cb(struct inode *inode, struct ceph_cap *cap, 
	} else {

		err = ceph_pagelist_append(pagelist, &rec, reclen);

	}



	recon_state->nr_caps++;

out_free:

	kfree(path);

out_dput:
@@ -2576,6 +2579,7 @@ static void send_mds_reconnect(struct ceph_mds_client *mdsc, 
	struct rb_node *p;

	int mds = session->s_mds;

	int err = -ENOMEM;

	int s_nr_caps;

	struct ceph_pagelist *pagelist;

	struct ceph_reconnect_state recon_state;
@@ -2611,10 +2615,12 @@ static void send_mds_reconnect(struct ceph_mds_client *mdsc, 
	discard_cap_releases(mdsc, session);



	/* traverse this session's caps */

	err = ceph_pagelist_encode_32(pagelist, session->s_nr_caps);

	s_nr_caps = session->s_nr_caps;

	err = ceph_pagelist_encode_32(pagelist, s_nr_caps);

	if (err)

		goto fail;



	recon_state.nr_caps = 0;

	recon_state.pagelist = pagelist;

	recon_state.flock = session->s_con.peer_features & CEPH_FEATURE_FLOCK;

	err = iterate_session_caps(session, encode_caps_cb, &recon_state);
@@ -2643,11 +2649,18 @@ static void send_mds_reconnect(struct ceph_mds_client *mdsc, 


	if (recon_state.flock)

		reply->hdr.version = cpu_to_le16(2);

	if (pagelist->length) {

		/* set up outbound data if we have any */



	/* raced with cap release? */

	if (s_nr_caps != recon_state.nr_caps) {

		struct page *page = list_first_entry(&pagelist->head,

						     struct page, lru);

		__le32 *addr = kmap_atomic(page);

		*addr = cpu_to_le32(recon_state.nr_caps);

		kunmap_atomic(addr);

	}



	reply->hdr.data_len = cpu_to_le32(pagelist->length);

	ceph_msg_data_add_pagelist(reply, pagelist);

	}

	ceph_con_send(&session->s_con, reply);



	mutex_unlock(&session->s_mutex);