From: "Yan, Zheng" <zyan@redhat.com>
Date: Thu, 13 Dec 2018 16:34:11 +0800
Subject: ceph: don't encode inode pathes into reconnect message
Git-commit: 5ccedf1ccd710ba32f36986b49eeb764e53e7ef1
Patch-mainline: v5.0-rc1
References: bsc#1122215

mds hasn't used inode pathes since introducing inode backtrace.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Acked-by: Luis Henriques <lhenriques@suse.com>
---
 fs/ceph/mds_client.c |   96 ++++++++++++++++++++++++++-------------------------
 1 file changed, 50 insertions(+), 46 deletions(-)

--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -2958,11 +2958,8 @@ static int encode_caps_cb(struct inode *
 	struct ceph_inode_info *ci = cap->ci;
 	struct ceph_reconnect_state *recon_state = arg;
 	struct ceph_pagelist *pagelist = recon_state->pagelist;
-	char *path;
-	int pathlen, err;
-	u64 pathbase;
+	int err;
 	u64 snap_follows;
-	struct dentry *dentry;
 
 	dout(" adding %p ino %llx.%llx cap %p %lld %s\n",
 	     inode, ceph_vinop(inode), cap, cap->cap_id,
@@ -2971,19 +2968,6 @@ static int encode_caps_cb(struct inode *
 	if (err)
 		return err;
 
-	dentry = d_find_alias(inode);
-	if (dentry) {
-		path = ceph_mdsc_build_path(dentry, &pathlen, &pathbase, 0);
-		if (IS_ERR(path)) {
-			err = PTR_ERR(path);
-			goto out_dput;
-		}
-	} else {
-		path = NULL;
-		pathlen = 0;
-		pathbase = 0;
-	}
-
 	spin_lock(&ci->i_ceph_lock);
 	cap->seq = 0;        /* reset cap seq */
 	cap->issue_seq = 0;  /* and issue_seq */
@@ -2995,7 +2979,7 @@ static int encode_caps_cb(struct inode *
 		rec.v2.wanted = cpu_to_le32(__ceph_caps_wanted(ci));
 		rec.v2.issued = cpu_to_le32(cap->issued);
 		rec.v2.snaprealm = cpu_to_le64(ci->i_snap_realm->ino);
-		rec.v2.pathbase = cpu_to_le64(pathbase);
+		rec.v2.pathbase = 0;
 		rec.v2.flock_len = (__force __le32)
 			((ci->i_ceph_flags & CEPH_I_ERROR_FILELOCK) ? 0 : 1);
 	} else {
@@ -3006,7 +2990,7 @@ static int encode_caps_cb(struct inode *
 		ceph_encode_timespec(&rec.v1.mtime, &inode->i_mtime);
 		ceph_encode_timespec(&rec.v1.atime, &inode->i_atime);
 		rec.v1.snaprealm = cpu_to_le64(ci->i_snap_realm->ino);
-		rec.v1.pathbase = cpu_to_le64(pathbase);
+		rec.v1.pathbase = 0;
 	}
 
 	if (list_empty(&ci->i_cap_snaps)) {
@@ -3037,7 +3021,7 @@ encode_again:
 					 sizeof(struct ceph_filelock), GFP_NOFS);
 			if (!flocks) {
 				err = -ENOMEM;
-				goto out_free;
+				goto out_err;
 			}
 			err = ceph_encode_locks_to_buffer(inode, flocks,
 							  num_fcntl_locks,
@@ -3047,7 +3031,7 @@ encode_again:
 				flocks = NULL;
 				if (err == -ENOSPC)
 					goto encode_again;
-				goto out_free;
+				goto out_err;
 			}
 		} else {
 			kfree(flocks);
@@ -3067,44 +3051,64 @@ encode_again:
 			    sizeof(struct ceph_filelock);
 		rec.v2.flock_len = cpu_to_le32(struct_len);
 
-		struct_len += sizeof(rec.v2);
-		struct_len += sizeof(u32) + pathlen;
+		struct_len += sizeof(u32) + sizeof(rec.v2);
 
 		if (struct_v >= 2)
 			struct_len += sizeof(u64); /* snap_follows */
 
 		total_len += struct_len;
 		err = ceph_pagelist_reserve(pagelist, total_len);
-
-		if (!err) {
-			if (recon_state->msg_version >= 3) {
-				ceph_pagelist_encode_8(pagelist, struct_v);
-				ceph_pagelist_encode_8(pagelist, 1);
-				ceph_pagelist_encode_32(pagelist, struct_len);
-			}
-			ceph_pagelist_encode_string(pagelist, path, pathlen);
-			ceph_pagelist_append(pagelist, &rec, sizeof(rec.v2));
-			ceph_locks_to_pagelist(flocks, pagelist,
-					       num_fcntl_locks,
-					       num_flock_locks);
-			if (struct_v >= 2)
-				ceph_pagelist_encode_64(pagelist, snap_follows);
+		if (err) {
+			kfree(flocks);
+			goto out_err;
 		}
+
+		if (recon_state->msg_version >= 3) {
+			ceph_pagelist_encode_8(pagelist, struct_v);
+			ceph_pagelist_encode_8(pagelist, 1);
+			ceph_pagelist_encode_32(pagelist, struct_len);
+		}
+		ceph_pagelist_encode_string(pagelist, NULL, 0);
+		ceph_pagelist_append(pagelist, &rec, sizeof(rec.v2));
+		ceph_locks_to_pagelist(flocks, pagelist,
+				       num_fcntl_locks, num_flock_locks);
+		if (struct_v >= 2)
+			ceph_pagelist_encode_64(pagelist, snap_follows);
+
 		kfree(flocks);
 	} else {
-		size_t size = sizeof(u32) + pathlen + sizeof(rec.v1);
-		err = ceph_pagelist_reserve(pagelist, size);
-		if (!err) {
-			ceph_pagelist_encode_string(pagelist, path, pathlen);
-			ceph_pagelist_append(pagelist, &rec, sizeof(rec.v1));
+		u64 pathbase = 0;
+		int pathlen = 0;
+		char *path = NULL;
+		struct dentry *dentry;
+
+		dentry = d_find_alias(inode);
+		if (dentry) {
+			path = ceph_mdsc_build_path(dentry,
+						&pathlen, &pathbase, 0);
+			dput(dentry);
+			if (IS_ERR(path)) {
+				err = PTR_ERR(path);
+				goto out_err;
+			}
+			rec.v1.pathbase = cpu_to_le64(pathbase);
 		}
+
+		err = ceph_pagelist_reserve(pagelist,
+				pathlen + sizeof(u32) + sizeof(rec.v1));
+		if (err) {
+			kfree(path);
+			goto out_err;
+		}
+
+		ceph_pagelist_encode_string(pagelist, path, pathlen);
+		ceph_pagelist_append(pagelist, &rec, sizeof(rec.v1));
+
+		kfree(path);
 	}
 
 	recon_state->nr_caps++;
-out_free:
-	kfree(path);
-out_dput:
-	dput(dentry);
+out_err:
 	return err;
 }