ceph: pre-allocate ceph_cap struct for ceph_add_cap()
So that ceph_add_cap() can be used while i_ceph_lock is locked.
This simplifies the code that handle cap import/export.
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 5f6d24e..73a42f5 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -221,8 +221,8 @@
return 0;
}
-static struct ceph_cap *get_cap(struct ceph_mds_client *mdsc,
- struct ceph_cap_reservation *ctx)
+struct ceph_cap *ceph_get_cap(struct ceph_mds_client *mdsc,
+ struct ceph_cap_reservation *ctx)
{
struct ceph_cap *cap = NULL;
@@ -508,15 +508,14 @@
* it is < 0. (This is so we can atomically add the cap and add an
* open file reference to it.)
*/
-int ceph_add_cap(struct inode *inode,
- struct ceph_mds_session *session, u64 cap_id,
- int fmode, unsigned issued, unsigned wanted,
- unsigned seq, unsigned mseq, u64 realmino, int flags,
- struct ceph_cap_reservation *caps_reservation)
+void ceph_add_cap(struct inode *inode,
+ struct ceph_mds_session *session, u64 cap_id,
+ int fmode, unsigned issued, unsigned wanted,
+ unsigned seq, unsigned mseq, u64 realmino, int flags,
+ struct ceph_cap **new_cap)
{
struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
struct ceph_inode_info *ci = ceph_inode(inode);
- struct ceph_cap *new_cap = NULL;
struct ceph_cap *cap;
int mds = session->s_mds;
int actual_wanted;
@@ -531,20 +530,10 @@
if (fmode >= 0)
wanted |= ceph_caps_for_mode(fmode);
-retry:
- spin_lock(&ci->i_ceph_lock);
cap = __get_cap_for_mds(ci, mds);
if (!cap) {
- if (new_cap) {
- cap = new_cap;
- new_cap = NULL;
- } else {
- spin_unlock(&ci->i_ceph_lock);
- new_cap = get_cap(mdsc, caps_reservation);
- if (new_cap == NULL)
- return -ENOMEM;
- goto retry;
- }
+ cap = *new_cap;
+ *new_cap = NULL;
cap->issued = 0;
cap->implemented = 0;
@@ -562,9 +551,6 @@
session->s_nr_caps++;
spin_unlock(&session->s_cap_lock);
} else {
- if (new_cap)
- ceph_put_cap(mdsc, new_cap);
-
/*
* auth mds of the inode changed. we received the cap export
* message, but still haven't received the cap import message.
@@ -626,7 +612,6 @@
ci->i_auth_cap = cap;
cap->mds_wanted = wanted;
}
- ci->i_cap_exporting_issued = 0;
} else {
WARN_ON(ci->i_auth_cap == cap);
}
@@ -648,9 +633,6 @@
if (fmode >= 0)
__ceph_get_fmode(ci, fmode);
- spin_unlock(&ci->i_ceph_lock);
- wake_up_all(&ci->i_cap_wq);
- return 0;
}
/*
@@ -685,7 +667,7 @@
*/
int __ceph_caps_issued(struct ceph_inode_info *ci, int *implemented)
{
- int have = ci->i_snap_caps | ci->i_cap_exporting_issued;
+ int have = ci->i_snap_caps;
struct ceph_cap *cap;
struct rb_node *p;
@@ -900,7 +882,7 @@
*/
static int __ceph_is_any_caps(struct ceph_inode_info *ci)
{
- return !RB_EMPTY_ROOT(&ci->i_caps) || ci->i_cap_exporting_issued;
+ return !RB_EMPTY_ROOT(&ci->i_caps);
}
int ceph_is_any_caps(struct inode *inode)
@@ -2796,7 +2778,7 @@
{
struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
struct ceph_mds_session *tsession = NULL;
- struct ceph_cap *cap, *tcap;
+ struct ceph_cap *cap, *tcap, *new_cap = NULL;
struct ceph_inode_info *ci = ceph_inode(inode);
u64 t_cap_id;
unsigned mseq = le32_to_cpu(ex->migrate_seq);
@@ -2858,15 +2840,14 @@
}
__ceph_remove_cap(cap, false);
goto out_unlock;
- }
-
- if (tsession) {
- int flag = (cap == ci->i_auth_cap) ? CEPH_CAP_FLAG_AUTH : 0;
- spin_unlock(&ci->i_ceph_lock);
+ } else if (tsession) {
/* add placeholder for the export tagert */
+ int flag = (cap == ci->i_auth_cap) ? CEPH_CAP_FLAG_AUTH : 0;
ceph_add_cap(inode, tsession, t_cap_id, -1, issued, 0,
- t_seq - 1, t_mseq, (u64)-1, flag, NULL);
- goto retry;
+ t_seq - 1, t_mseq, (u64)-1, flag, &new_cap);
+
+ __ceph_remove_cap(cap, false);
+ goto out_unlock;
}
spin_unlock(&ci->i_ceph_lock);
@@ -2885,6 +2866,7 @@
SINGLE_DEPTH_NESTING);
}
ceph_add_cap_releases(mdsc, tsession);
+ new_cap = ceph_get_cap(mdsc, NULL);
} else {
WARN_ON(1);
tsession = NULL;
@@ -2899,6 +2881,8 @@
mutex_unlock(&tsession->s_mutex);
ceph_put_mds_session(tsession);
}
+ if (new_cap)
+ ceph_put_cap(mdsc, new_cap);
}
/*
@@ -2914,7 +2898,7 @@
void *snaptrace, int snaptrace_len)
{
struct ceph_inode_info *ci = ceph_inode(inode);
- struct ceph_cap *cap;
+ struct ceph_cap *cap, *new_cap = NULL;
int mds = session->s_mds;
unsigned issued = le32_to_cpu(im->caps);
unsigned wanted = le32_to_cpu(im->wanted);
@@ -2936,7 +2920,20 @@
dout("handle_cap_import inode %p ci %p mds%d mseq %d peer %d\n",
inode, ci, mds, mseq, peer);
+retry:
spin_lock(&ci->i_ceph_lock);
+ cap = __get_cap_for_mds(ci, mds);
+ if (!cap) {
+ if (!new_cap) {
+ spin_unlock(&ci->i_ceph_lock);
+ new_cap = ceph_get_cap(mdsc, NULL);
+ goto retry;
+ }
+ }
+
+ ceph_add_cap(inode, session, cap_id, -1, issued, wanted, seq, mseq,
+ realmino, CEPH_CAP_FLAG_AUTH, &new_cap);
+
cap = peer >= 0 ? __get_cap_for_mds(ci, peer) : NULL;
if (cap && cap->cap_id == p_cap_id) {
dout(" remove export cap %p mds%d flags %d\n",
@@ -2951,7 +2948,6 @@
cap->mseq, mds, le32_to_cpu(ph->seq),
le32_to_cpu(ph->mseq));
}
- ci->i_cap_exporting_issued = cap->issued;
__ceph_remove_cap(cap, (ph->flags & CEPH_CAP_FLAG_RELEASE));
}
@@ -2960,16 +2956,17 @@
ci->i_requested_max_size = 0;
spin_unlock(&ci->i_ceph_lock);
+ wake_up_all(&ci->i_cap_wq);
+
down_write(&mdsc->snap_rwsem);
ceph_update_snap_trace(mdsc, snaptrace, snaptrace+snaptrace_len,
false);
downgrade_write(&mdsc->snap_rwsem);
- ceph_add_cap(inode, session, cap_id, -1,
- issued, wanted, seq, mseq, realmino, CEPH_CAP_FLAG_AUTH,
- NULL /* no caps context */);
kick_flushing_inode_caps(mdsc, session, inode);
up_read(&mdsc->snap_rwsem);
+ if (new_cap)
+ ceph_put_cap(mdsc, new_cap);
}
/*