1 files changed, 85 insertions, 15 deletions

diff --git a/fs/nfs/nfs3acl.c b/fs/nfs/nfs3acl.c
index 89b6468700e7..451112ff9aa4 100644
--- a/fs/nfs/nfs3acl.c
+++ b/fs/nfs/nfs3acl.c
@@ -113,6 +113,69 @@ int nfs3_removexattr(struct dentry *dentry, const char *name)
         return nfs3_proc_setacl(inode, type, NULL);
 }
 
+static void __nfs3_forget_cached_acls(struct nfs_inode *nfsi)
+{
+        if (nfsi->acl_access != ERR_PTR(-EAGAIN)) {
+                posix_acl_release(nfsi->acl_access);
+                nfsi->acl_access = ERR_PTR(-EAGAIN);
+        }
+        if (nfsi->acl_default != ERR_PTR(-EAGAIN)) {
+                posix_acl_release(nfsi->acl_default);
+                nfsi->acl_default = ERR_PTR(-EAGAIN);
+        }
+}
+
+void nfs3_forget_cached_acls(struct inode *inode)
+{
+        dprintk("NFS: nfs3_forget_cached_acls(%s/%ld)\n", inode->i_sb->s_id,
+                inode->i_ino);
+        spin_lock(&inode->i_lock);
+        __nfs3_forget_cached_acls(NFS_I(inode));
+        spin_unlock(&inode->i_lock);
+}
+
+static struct posix_acl *nfs3_get_cached_acl(struct inode *inode, int type)
+{
+        struct nfs_inode *nfsi = NFS_I(inode);
+        struct posix_acl *acl = ERR_PTR(-EAGAIN);
+
+        spin_lock(&inode->i_lock);
+        switch(type) {
+                case ACL_TYPE_ACCESS:
+                        acl = nfsi->acl_access;
+                        break;
+
+                case ACL_TYPE_DEFAULT:
+                        acl = nfsi->acl_default;
+                        break;
+
+                default:
+                        return ERR_PTR(-EINVAL);
+        }
+        if (acl == ERR_PTR(-EAGAIN))
+                acl = ERR_PTR(-EAGAIN);
+        else
+                acl = posix_acl_dup(acl);
+        spin_unlock(&inode->i_lock);
+        dprintk("NFS: nfs3_get_cached_acl(%s/%ld, %d) = %p\n", inode->i_sb->s_id,
+                inode->i_ino, type, acl);
+        return acl;
+}
+
+static void nfs3_cache_acls(struct inode *inode, struct posix_acl *acl,
+                    struct posix_acl *dfacl)
+{
+        struct nfs_inode *nfsi = NFS_I(inode);
+
+        dprintk("nfs3_cache_acls(%s/%ld, %p, %p)\n", inode->i_sb->s_id,
+                inode->i_ino, acl, dfacl);
+        spin_lock(&inode->i_lock);
+        __nfs3_forget_cached_acls(NFS_I(inode));
+        nfsi->acl_access = posix_acl_dup(acl);
+        nfsi->acl_default = posix_acl_dup(dfacl);
+        spin_unlock(&inode->i_lock);
+}
+
 struct posix_acl *nfs3_proc_getacl(struct inode *inode, int type)
 {
         struct nfs_server *server = NFS_SERVER(inode);
@@ -126,26 +189,32 @@ struct posix_acl *nfs3_proc_getacl(struct inode *inode, int type)
         struct nfs3_getaclres res = {
                 .fattr =        &fattr,
         };
-        struct posix_acl *acl = NULL;
+        struct posix_acl *acl;
         int status, count;
 
         if (!nfs_server_capable(inode, NFS_CAP_ACLS))
                 return ERR_PTR(-EOPNOTSUPP);
 
-        switch (type) {
-                case ACL_TYPE_ACCESS:
-                        args.mask = NFS_ACLCNT|NFS_ACL;
-                        break;
-
-                case ACL_TYPE_DEFAULT:
-                        if (!S_ISDIR(inode->i_mode))
-                                return NULL;
-                        args.mask = NFS_DFACLCNT|NFS_DFACL;
-                        break;
-
-                default:
-                        return ERR_PTR(-EINVAL);
-        }
+        status = nfs_revalidate_inode(server, inode);
+        if (status < 0)
+                return ERR_PTR(status);
+        acl = nfs3_get_cached_acl(inode, type);
+        if (acl != ERR_PTR(-EAGAIN))
+                return acl;
+        acl = NULL;
+
+        /*
+         * Only get the access acl when explicitly requested: We don't
+         * need it for access decisions, and only some applications use
+         * it. Applications which request the access acl first are not
+         * penalized from this optimization.
+         */
+        if (type == ACL_TYPE_ACCESS)
+                args.mask |= NFS_ACLCNT|NFS_ACL;
+        if (S_ISDIR(inode->i_mode))
+                args.mask |= NFS_DFACLCNT|NFS_DFACL;
+        if (args.mask == 0)
+                return NULL;
 
         dprintk("NFS call getacl\n");
         status = rpc_call(server->client_acl, ACLPROC3_GETACL,
@@ -180,6 +249,7 @@ struct posix_acl *nfs3_proc_getacl(struct inode *inode, int type)
                         res.acl_access = NULL;
                 }
         }
+        nfs3_cache_acls(inode, res.acl_access, res.acl_default);
 
         switch(type) {
                 case ACL_TYPE_ACCESS: