[PATCH 7/8] ceph: ensure d_name/d_parent stability in ceph_mdsc_lease_send_msg()

From: Yan, Zheng
Date: Thu May 23 2019 - 04:09:57 EST


Signed-off-by: "Yan, Zheng" <zyan@xxxxxxxxxx>
---
fs/ceph/dir.c | 7 +++----
fs/ceph/mds_client.c | 24 +++++++++++++-----------
fs/ceph/mds_client.h | 1 -
3 files changed, 16 insertions(+), 16 deletions(-)

diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index 1271024a3797..72efad28857c 100644
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -1433,8 +1433,7 @@ static bool __dentry_lease_is_valid(struct ceph_dentry_info *di)
return false;
}

-static int dentry_lease_is_valid(struct dentry *dentry, unsigned int flags,
- struct inode *dir)
+static int dentry_lease_is_valid(struct dentry *dentry, unsigned int flags)
{
struct ceph_dentry_info *di;
struct ceph_mds_session *session = NULL;
@@ -1466,7 +1465,7 @@ static int dentry_lease_is_valid(struct dentry *dentry, unsigned int flags,
spin_unlock(&dentry->d_lock);

if (session) {
- ceph_mdsc_lease_send_msg(session, dir, dentry,
+ ceph_mdsc_lease_send_msg(session, dentry,
CEPH_MDS_LEASE_RENEW, seq);
ceph_put_mds_session(session);
}
@@ -1566,7 +1565,7 @@ static int ceph_d_revalidate(struct dentry *dentry, unsigned int flags)
ceph_snap(d_inode(dentry)) == CEPH_SNAPDIR) {
valid = 1;
} else {
- valid = dentry_lease_is_valid(dentry, flags, dir);
+ valid = dentry_lease_is_valid(dentry, flags);
if (valid == -ECHILD)
return valid;
if (valid || dir_lease_is_valid(dir, dentry)) {
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 870754e9d572..98c500dbec3f 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -3941,31 +3941,33 @@ static void handle_lease(struct ceph_mds_client *mdsc,
}

void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session,
- struct inode *inode,
struct dentry *dentry, char action,
u32 seq)
{
struct ceph_msg *msg;
struct ceph_mds_lease *lease;
- int len = sizeof(*lease) + sizeof(u32);
- int dnamelen = 0;
+ struct inode *dir;
+ int len = sizeof(*lease) + sizeof(u32) + NAME_MAX;

- dout("lease_send_msg inode %p dentry %p %s to mds%d\n",
- inode, dentry, ceph_lease_op_name(action), session->s_mds);
- dnamelen = dentry->d_name.len;
- len += dnamelen;
+ dout("lease_send_msg identry %p %s to mds%d\n",
+ dentry, ceph_lease_op_name(action), session->s_mds);

msg = ceph_msg_new(CEPH_MSG_CLIENT_LEASE, len, GFP_NOFS, false);
if (!msg)
return;
lease = msg->front.iov_base;
lease->action = action;
- lease->ino = cpu_to_le64(ceph_vino(inode).ino);
- lease->first = lease->last = cpu_to_le64(ceph_vino(inode).snap);
lease->seq = cpu_to_le32(seq);
- put_unaligned_le32(dnamelen, lease + 1);
- memcpy((void *)(lease + 1) + 4, dentry->d_name.name, dnamelen);

+ spin_lock(&dentry->d_lock);
+ dir = d_inode(dentry->d_parent);
+ lease->ino = cpu_to_le64(ceph_inode(dir)->i_vino.ino);
+ lease->first = lease->last = cpu_to_le64(ceph_inode(dir)->i_vino.snap);
+
+ put_unaligned_le32(dentry->d_name.len, lease + 1);
+ memcpy((void *)(lease + 1) + 4,
+ dentry->d_name.name, dentry->d_name.len);
+ spin_unlock(&dentry->d_lock);
/*
* if this is a preemptive lease RELEASE, no need to
* flush request stream, since the actual request will
diff --git a/fs/ceph/mds_client.h b/fs/ceph/mds_client.h
index 9c28b86abcf4..330769ecb601 100644
--- a/fs/ceph/mds_client.h
+++ b/fs/ceph/mds_client.h
@@ -505,7 +505,6 @@ extern char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *base,

extern void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry);
extern void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session,
- struct inode *inode,
struct dentry *dentry, char action,
u32 seq);

--
2.17.2