nfsd: Add fine grained protection for the nfs4_file->fi_stateids list
Access to this list is currently serialized by the client_mutex. Add
finer grained locking around this list in preparation for its removal.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 3704789..cfb10d0 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -708,7 +708,11 @@
static void unhash_generic_stateid(struct nfs4_ol_stateid *stp)
{
+ struct nfs4_file *fp = stp->st_file;
+
+ spin_lock(&fp->fi_lock);
list_del(&stp->st_perfile);
+ spin_unlock(&fp->fi_lock);
list_del(&stp->st_perstateowner);
}
@@ -2676,6 +2680,7 @@
lockdep_assert_held(&state_lock);
atomic_set(&fp->fi_ref, 1);
+ spin_lock_init(&fp->fi_lock);
INIT_LIST_HEAD(&fp->fi_stateids);
INIT_LIST_HEAD(&fp->fi_delegations);
ihold(ino);
@@ -2799,7 +2804,6 @@
stp->st_stid.sc_type = NFS4_OPEN_STID;
INIT_LIST_HEAD(&stp->st_locks);
list_add(&stp->st_perstateowner, &oo->oo_owner.so_stateids);
- list_add(&stp->st_perfile, &fp->fi_stateids);
stp->st_stateowner = &oo->oo_owner;
get_nfs4_file(fp);
stp->st_file = fp;
@@ -2808,6 +2812,9 @@
set_access(open->op_share_access, stp);
set_deny(open->op_share_deny, stp);
stp->st_openstp = NULL;
+ spin_lock(&fp->fi_lock);
+ list_add(&stp->st_perfile, &fp->fi_stateids);
+ spin_unlock(&fp->fi_lock);
}
static void
@@ -2915,6 +2922,7 @@
return nfs_ok;
ret = nfserr_locked;
/* Search for conflicting share reservations */
+ spin_lock(&fp->fi_lock);
list_for_each_entry(stp, &fp->fi_stateids, st_perfile) {
if (test_deny(deny_type, stp) ||
test_deny(NFS4_SHARE_DENY_BOTH, stp))
@@ -2922,6 +2930,7 @@
}
ret = nfs_ok;
out:
+ spin_unlock(&fp->fi_lock);
put_nfs4_file(fp);
return ret;
}
@@ -3150,6 +3159,7 @@
struct nfs4_ol_stateid *local;
struct nfs4_openowner *oo = open->op_openowner;
+ spin_lock(&fp->fi_lock);
list_for_each_entry(local, &fp->fi_stateids, st_perfile) {
/* ignore lock owners */
if (local->st_stateowner->so_is_open_owner == 0)
@@ -3158,9 +3168,12 @@
if (local->st_stateowner == &oo->oo_owner)
*stpp = local;
/* check for conflicting share reservations */
- if (!test_share(local, open))
+ if (!test_share(local, open)) {
+ spin_unlock(&fp->fi_lock);
return nfserr_share_denied;
+ }
}
+ spin_unlock(&fp->fi_lock);
return nfs_ok;
}
@@ -4408,7 +4421,6 @@
if (stp == NULL)
return NULL;
stp->st_stid.sc_type = NFS4_LOCK_STID;
- list_add(&stp->st_perfile, &fp->fi_stateids);
list_add(&stp->st_perstateowner, &lo->lo_owner.so_stateids);
stp->st_stateowner = &lo->lo_owner;
get_nfs4_file(fp);
@@ -4417,6 +4429,9 @@
stp->st_deny_bmap = open_stp->st_deny_bmap;
stp->st_openstp = open_stp;
list_add(&stp->st_locks, &open_stp->st_locks);
+ spin_lock(&fp->fi_lock);
+ list_add(&stp->st_perfile, &fp->fi_stateids);
+ spin_unlock(&fp->fi_lock);
return stp;
}
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index 06d1a90..04737b3 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -377,6 +377,7 @@
/* nfs4_file: a file opened by some number of (open) nfs4_stateowners. */
struct nfs4_file {
atomic_t fi_ref;
+ spinlock_t fi_lock;
struct hlist_node fi_hash; /* hash by "struct inode *" */
struct list_head fi_stateids;
struct list_head fi_delegations;