Merge branch 'master' into upstream
[pandora-kernel.git] / fs / nfsd / nfs4acl.c
index 5d94555..832673b 100644 (file)
 
 /* flags used to simulate posix default ACLs */
 #define NFS4_INHERITANCE_FLAGS (NFS4_ACE_FILE_INHERIT_ACE \
-               | NFS4_ACE_DIRECTORY_INHERIT_ACE | NFS4_ACE_INHERIT_ONLY_ACE)
+               | NFS4_ACE_DIRECTORY_INHERIT_ACE)
 
-#define NFS4_SUPPORTED_FLAGS (NFS4_INHERITANCE_FLAGS | NFS4_ACE_IDENTIFIER_GROUP)
+#define NFS4_SUPPORTED_FLAGS (NFS4_INHERITANCE_FLAGS \
+               | NFS4_ACE_INHERIT_ONLY_ACE \
+               | NFS4_ACE_IDENTIFIER_GROUP)
 
 #define MASK_EQUAL(mask1, mask2) \
        ( ((mask1) & NFS4_ACE_MASK_ALL) == ((mask2) & NFS4_ACE_MASK_ALL) )
@@ -87,12 +89,19 @@ mask_from_posix(unsigned short perm, unsigned int flags)
 }
 
 static u32
-deny_mask(u32 allow_mask, unsigned int flags)
+deny_mask_from_posix(unsigned short perm, u32 flags)
 {
-       u32 ret = ~allow_mask & ~NFS4_MASK_UNSUPP;
-       if (!(flags & NFS4_ACL_DIR))
-               ret &= ~NFS4_ACE_DELETE_CHILD;
-       return ret;
+       u32 mask = 0;
+
+       if (perm & ACL_READ)
+               mask |= NFS4_READ_MODE;
+       if (perm & ACL_WRITE)
+               mask |= NFS4_WRITE_MODE;
+       if ((perm & ACL_WRITE) && (flags & NFS4_ACL_DIR))
+               mask |= NFS4_ACE_DELETE_CHILD;
+       if (perm & ACL_EXECUTE)
+               mask |= NFS4_EXECUTE_MODE;
+       return mask;
 }
 
 /* XXX: modify functions to return NFS errors; they're only ever
@@ -126,108 +135,151 @@ struct ace_container {
 };
 
 static short ace2type(struct nfs4_ace *);
-static int _posix_to_nfsv4_one(struct posix_acl *, struct nfs4_acl *, unsigned int);
-static struct posix_acl *_nfsv4_to_posix_one(struct nfs4_acl *, unsigned int);
-int nfs4_acl_add_ace(struct nfs4_acl *, u32, u32, u32, int, uid_t);
-static int nfs4_acl_split(struct nfs4_acl *, struct nfs4_acl *);
+static void _posix_to_nfsv4_one(struct posix_acl *, struct nfs4_acl *,
+                               unsigned int);
+void nfs4_acl_add_ace(struct nfs4_acl *, u32, u32, u32, int, uid_t);
 
 struct nfs4_acl *
 nfs4_acl_posix_to_nfsv4(struct posix_acl *pacl, struct posix_acl *dpacl,
                        unsigned int flags)
 {
        struct nfs4_acl *acl;
-       int error = -EINVAL;
+       int size = 0;
 
-       if ((pacl != NULL &&
-               (posix_acl_valid(pacl) < 0 || pacl->a_count == 0)) ||
-           (dpacl != NULL &&
-               (posix_acl_valid(dpacl) < 0 || dpacl->a_count == 0)))
-               goto out_err;
-
-       acl = nfs4_acl_new();
-       if (acl == NULL) {
-               error = -ENOMEM;
-               goto out_err;
+       if (pacl) {
+               if (posix_acl_valid(pacl) < 0)
+                       return ERR_PTR(-EINVAL);
+               size += 2*pacl->a_count;
        }
-
-       if (pacl != NULL) {
-               error = _posix_to_nfsv4_one(pacl, acl,
-                                               flags & ~NFS4_ACL_TYPE_DEFAULT);
-               if (error < 0)
-                       goto out_acl;
+       if (dpacl) {
+               if (posix_acl_valid(dpacl) < 0)
+                       return ERR_PTR(-EINVAL);
+               size += 2*dpacl->a_count;
        }
 
-       if (dpacl != NULL) {
-               error = _posix_to_nfsv4_one(dpacl, acl,
-                                               flags | NFS4_ACL_TYPE_DEFAULT);
-               if (error < 0)
-                       goto out_acl;
-       }
+       /* Allocate for worst case: one (deny, allow) pair each: */
+       acl = nfs4_acl_new(size);
+       if (acl == NULL)
+               return ERR_PTR(-ENOMEM);
 
-       return acl;
+       if (pacl)
+               _posix_to_nfsv4_one(pacl, acl, flags & ~NFS4_ACL_TYPE_DEFAULT);
 
-out_acl:
-       nfs4_acl_free(acl);
-out_err:
-       acl = ERR_PTR(error);
+       if (dpacl)
+               _posix_to_nfsv4_one(dpacl, acl, flags | NFS4_ACL_TYPE_DEFAULT);
 
        return acl;
 }
 
-static int
-nfs4_acl_add_pair(struct nfs4_acl *acl, int eflag, u32 mask, int whotype,
-               uid_t owner, unsigned int flags)
+struct posix_acl_summary {
+       unsigned short owner;
+       unsigned short users;
+       unsigned short group;
+       unsigned short groups;
+       unsigned short other;
+       unsigned short mask;
+};
+
+static void
+summarize_posix_acl(struct posix_acl *acl, struct posix_acl_summary *pas)
 {
-       int error;
-
-       error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE,
-                                eflag, mask, whotype, owner);
-       if (error < 0)
-               return error;
-       error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_DENIED_ACE_TYPE,
-                               eflag, deny_mask(mask, flags), whotype, owner);
-       return error;
+       struct posix_acl_entry *pa, *pe;
+       pas->users = 0;
+       pas->groups = 0;
+       pas->mask = 07;
+
+       pe = acl->a_entries + acl->a_count;
+
+       FOREACH_ACL_ENTRY(pa, acl, pe) {
+               switch (pa->e_tag) {
+                       case ACL_USER_OBJ:
+                               pas->owner = pa->e_perm;
+                               break;
+                       case ACL_GROUP_OBJ:
+                               pas->group = pa->e_perm;
+                               break;
+                       case ACL_USER:
+                               pas->users |= pa->e_perm;
+                               break;
+                       case ACL_GROUP:
+                               pas->groups |= pa->e_perm;
+                               break;
+                       case ACL_OTHER:
+                               pas->other = pa->e_perm;
+                               break;
+                       case ACL_MASK:
+                               pas->mask = pa->e_perm;
+                               break;
+               }
+       }
+       /* We'll only care about effective permissions: */
+       pas->users &= pas->mask;
+       pas->group &= pas->mask;
+       pas->groups &= pas->mask;
 }
 
 /* We assume the acl has been verified with posix_acl_valid. */
-static int
+static void
 _posix_to_nfsv4_one(struct posix_acl *pacl, struct nfs4_acl *acl,
                                                unsigned int flags)
 {
-       struct posix_acl_entry *pa, *pe, *group_owner_entry;
-       int error = -EINVAL;
-       u32 mask, mask_mask;
+       struct posix_acl_entry *pa, *group_owner_entry;
+       struct nfs4_ace *ace;
+       struct posix_acl_summary pas;
+       unsigned short deny;
        int eflag = ((flags & NFS4_ACL_TYPE_DEFAULT) ?
                                        NFS4_INHERITANCE_FLAGS : 0);
 
        BUG_ON(pacl->a_count < 3);
-       pe = pacl->a_entries + pacl->a_count;
-       pa = pe - 2; /* if mask entry exists, it's second from the last. */
-       if (pa->e_tag == ACL_MASK)
-               mask_mask = deny_mask(mask_from_posix(pa->e_perm, flags), flags);
-       else
-               mask_mask = 0;
+       summarize_posix_acl(pacl, &pas);
 
        pa = pacl->a_entries;
-       BUG_ON(pa->e_tag != ACL_USER_OBJ);
-       mask = mask_from_posix(pa->e_perm, flags | NFS4_ACL_OWNER);
-       error = nfs4_acl_add_pair(acl, eflag, mask, NFS4_ACL_WHO_OWNER, 0, flags);
-       if (error < 0)
-               goto out;
-       pa++;
+       ace = acl->aces + acl->naces;
 
-       while (pa->e_tag == ACL_USER) {
-               mask = mask_from_posix(pa->e_perm, flags);
-               error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_DENIED_ACE_TYPE,
-                               eflag,  mask_mask, NFS4_ACL_WHO_NAMED, pa->e_id);
-               if (error < 0)
-                       goto out;
+       /* We could deny everything not granted by the owner: */
+       deny = ~pas.owner;
+       /*
+        * but it is equivalent (and simpler) to deny only what is not
+        * granted by later entries:
+        */
+       deny &= pas.users | pas.group | pas.groups | pas.other;
+       if (deny) {
+               ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE;
+               ace->flag = eflag;
+               ace->access_mask = deny_mask_from_posix(deny, flags);
+               ace->whotype = NFS4_ACL_WHO_OWNER;
+               ace++;
+               acl->naces++;
+       }
 
+       ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE;
+       ace->flag = eflag;
+       ace->access_mask = mask_from_posix(pa->e_perm, flags | NFS4_ACL_OWNER);
+       ace->whotype = NFS4_ACL_WHO_OWNER;
+       ace++;
+       acl->naces++;
+       pa++;
 
-               error = nfs4_acl_add_pair(acl, eflag, mask,
-                               NFS4_ACL_WHO_NAMED, pa->e_id, flags);
-               if (error < 0)
-                       goto out;
+       while (pa->e_tag == ACL_USER) {
+               deny = ~(pa->e_perm & pas.mask);
+               deny &= pas.groups | pas.group | pas.other;
+               if (deny) {
+                       ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE;
+                       ace->flag = eflag;
+                       ace->access_mask = deny_mask_from_posix(deny, flags);
+                       ace->whotype = NFS4_ACL_WHO_NAMED;
+                       ace->who = pa->e_id;
+                       ace++;
+                       acl->naces++;
+               }
+               ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE;
+               ace->flag = eflag;
+               ace->access_mask = mask_from_posix(pa->e_perm & pas.mask,
+                                                  flags);
+               ace->whotype = NFS4_ACL_WHO_NAMED;
+               ace->who = pa->e_id;
+               ace++;
+               acl->naces++;
                pa++;
        }
 
@@ -236,67 +288,65 @@ _posix_to_nfsv4_one(struct posix_acl *pacl, struct nfs4_acl *acl,
 
        /* allow ACEs */
 
-       if (pacl->a_count > 3) {
-               BUG_ON(pa->e_tag != ACL_GROUP_OBJ);
-               error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_DENIED_ACE_TYPE,
-                               NFS4_ACE_IDENTIFIER_GROUP | eflag, mask_mask,
-                               NFS4_ACL_WHO_GROUP, 0);
-               if (error < 0)
-                       goto out;
-       }
        group_owner_entry = pa;
-       mask = mask_from_posix(pa->e_perm, flags);
-       error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE,
-                       NFS4_ACE_IDENTIFIER_GROUP | eflag, mask,
-                       NFS4_ACL_WHO_GROUP, 0);
-       if (error < 0)
-               goto out;
+
+       ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE;
+       ace->flag = eflag;
+       ace->access_mask = mask_from_posix(pas.group, flags);
+       ace->whotype = NFS4_ACL_WHO_GROUP;
+       ace++;
+       acl->naces++;
        pa++;
 
        while (pa->e_tag == ACL_GROUP) {
-               mask = mask_from_posix(pa->e_perm, flags);
-               error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_DENIED_ACE_TYPE,
-                               NFS4_ACE_IDENTIFIER_GROUP | eflag, mask_mask,
-                               NFS4_ACL_WHO_NAMED, pa->e_id);
-               if (error < 0)
-                       goto out;
-
-               error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE,
-                               NFS4_ACE_IDENTIFIER_GROUP | eflag, mask,
-                               NFS4_ACL_WHO_NAMED, pa->e_id);
-               if (error < 0)
-                       goto out;
+               ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE;
+               ace->flag = eflag | NFS4_ACE_IDENTIFIER_GROUP;
+               ace->access_mask = mask_from_posix(pa->e_perm & pas.mask,
+                                                  flags);
+               ace->whotype = NFS4_ACL_WHO_NAMED;
+               ace->who = pa->e_id;
+               ace++;
+               acl->naces++;
                pa++;
        }
 
        /* deny ACEs */
 
        pa = group_owner_entry;
-       mask = mask_from_posix(pa->e_perm, flags);
-       error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_DENIED_ACE_TYPE,
-                       NFS4_ACE_IDENTIFIER_GROUP | eflag,
-                       deny_mask(mask, flags), NFS4_ACL_WHO_GROUP, 0);
-       if (error < 0)
-               goto out;
+
+       deny = ~pas.group & pas.other;
+       if (deny) {
+               ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE;
+               ace->flag = eflag | NFS4_ACE_IDENTIFIER_GROUP;
+               ace->access_mask = deny_mask_from_posix(deny, flags);
+               ace->whotype = NFS4_ACL_WHO_GROUP;
+               ace++;
+               acl->naces++;
+       }
        pa++;
+
        while (pa->e_tag == ACL_GROUP) {
-               mask = mask_from_posix(pa->e_perm, flags);
-               error = nfs4_acl_add_ace(acl, NFS4_ACE_ACCESS_DENIED_ACE_TYPE,
-                               NFS4_ACE_IDENTIFIER_GROUP | eflag,
-                               deny_mask(mask, flags), NFS4_ACL_WHO_NAMED, pa->e_id);
-               if (error < 0)
-                       goto out;
+               deny = ~(pa->e_perm & pas.mask);
+               deny &= pas.other;
+               if (deny) {
+                       ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE;
+                       ace->flag = eflag | NFS4_ACE_IDENTIFIER_GROUP;
+                       ace->access_mask = mask_from_posix(deny, flags);
+                       ace->whotype = NFS4_ACL_WHO_NAMED;
+                       ace->who = pa->e_id;
+                       ace++;
+                       acl->naces++;
+               }
                pa++;
        }
 
        if (pa->e_tag == ACL_MASK)
                pa++;
-       BUG_ON(pa->e_tag != ACL_OTHER);
-       mask = mask_from_posix(pa->e_perm, flags);
-       error = nfs4_acl_add_pair(acl, eflag, mask, NFS4_ACL_WHO_EVERYONE, 0, flags);
-
-out:
-       return error;
+       ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE;
+       ace->flag = eflag;
+       ace->access_mask = mask_from_posix(pa->e_perm, flags);
+       ace->whotype = NFS4_ACL_WHO_EVERYONE;
+       acl->naces++;
 }
 
 static void
@@ -342,46 +392,6 @@ sort_pacl(struct posix_acl *pacl)
        return;
 }
 
-int
-nfs4_acl_nfsv4_to_posix(struct nfs4_acl *acl, struct posix_acl **pacl,
-               struct posix_acl **dpacl, unsigned int flags)
-{
-       struct nfs4_acl *dacl;
-       int error = -ENOMEM;
-
-       *pacl = NULL;
-       *dpacl = NULL;
-
-       dacl = nfs4_acl_new();
-       if (dacl == NULL)
-               goto out;
-
-       error = nfs4_acl_split(acl, dacl);
-       if (error)
-               goto out_acl;
-
-       *pacl = _nfsv4_to_posix_one(acl, flags);
-       if (IS_ERR(*pacl)) {
-               error = PTR_ERR(*pacl);
-               *pacl = NULL;
-               goto out_acl;
-       }
-
-       *dpacl = _nfsv4_to_posix_one(dacl, flags);
-       if (IS_ERR(*dpacl)) {
-               error = PTR_ERR(*dpacl);
-               *dpacl = NULL;
-       }
-out_acl:
-       if (error) {
-               posix_acl_release(*pacl);
-               *pacl = NULL;
-       }
-       nfs4_acl_free(dacl);
-out:
-       return error;
-}
-
 /*
  * While processing the NFSv4 ACE, this maintains bitmasks representing
  * which permission bits have been allowed and which denied to a given
@@ -406,6 +416,7 @@ struct posix_ace_state_array {
  * calculated so far: */
 
 struct posix_acl_state {
+       int empty;
        struct posix_ace_state owner;
        struct posix_ace_state group;
        struct posix_ace_state other;
@@ -421,6 +432,7 @@ init_state(struct posix_acl_state *state, int cnt)
        int alloc;
 
        memset(state, 0, sizeof(struct posix_acl_state));
+       state->empty = 1;
        /*
         * In the worst case, each individual acl could be for a distinct
         * named user or group, but we don't no which, so we allocate
@@ -488,6 +500,20 @@ posix_state_to_acl(struct posix_acl_state *state, unsigned int flags)
        int nace;
        int i, error = 0;
 
+       /*
+        * ACLs with no ACEs are treated differently in the inheritable
+        * and effective cases: when there are no inheritable ACEs, we
+        * set a zero-length default posix acl:
+        */
+       if (state->empty && (flags & NFS4_ACL_TYPE_DEFAULT)) {
+               pacl = posix_acl_alloc(0, GFP_KERNEL);
+               return pacl ? pacl : ERR_PTR(-ENOMEM);
+       }
+       /*
+        * When there are no effective ACEs, the following will end
+        * up setting a 3-element effective posix ACL with all
+        * permissions zero.
+        */
        nace = 4 + state->users->n + state->groups->n;
        pacl = posix_acl_alloc(nace, GFP_KERNEL);
        if (!pacl)
@@ -603,6 +629,8 @@ static void process_one_v4_ace(struct posix_acl_state *state,
        u32 mask = ace->access_mask;
        int i;
 
+       state->empty = 0;
+
        switch (ace2type(ace)) {
        case ACL_USER_OBJ:
                if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) {
@@ -666,75 +694,62 @@ static void process_one_v4_ace(struct posix_acl_state *state,
        }
 }
 
-static struct posix_acl *
-_nfsv4_to_posix_one(struct nfs4_acl *n4acl, unsigned int flags)
+int nfs4_acl_nfsv4_to_posix(struct nfs4_acl *acl, struct posix_acl **pacl,
+                           struct posix_acl **dpacl, unsigned int flags)
 {
-       struct posix_acl_state state;
-       struct posix_acl *pacl;
+       struct posix_acl_state effective_acl_state, default_acl_state;
        struct nfs4_ace *ace;
        int ret;
 
-       ret = init_state(&state, n4acl->naces);
+       ret = init_state(&effective_acl_state, acl->naces);
        if (ret)
-               return ERR_PTR(ret);
-
-       list_for_each_entry(ace, &n4acl->ace_head, l_ace)
-               process_one_v4_ace(&state, ace);
-
-       pacl = posix_state_to_acl(&state, flags);
-
-       free_state(&state);
-
-       if (!IS_ERR(pacl))
-               sort_pacl(pacl);
-       return pacl;
-}
-
-static int
-nfs4_acl_split(struct nfs4_acl *acl, struct nfs4_acl *dacl)
-{
-       struct list_head *h, *n;
-       struct nfs4_ace *ace;
-       int error = 0;
-
-       list_for_each_safe(h, n, &acl->ace_head) {
-               ace = list_entry(h, struct nfs4_ace, l_ace);
-
+               return ret;
+       ret = init_state(&default_acl_state, acl->naces);
+       if (ret)
+               goto out_estate;
+       ret = -EINVAL;
+       for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) {
                if (ace->type != NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE &&
                    ace->type != NFS4_ACE_ACCESS_DENIED_ACE_TYPE)
-                       return -EINVAL;
-
+                       goto out_dstate;
                if (ace->flag & ~NFS4_SUPPORTED_FLAGS)
-                       return -EINVAL;
-
-               switch (ace->flag & NFS4_INHERITANCE_FLAGS) {
-               case 0:
-                       /* Leave this ace in the effective acl: */
+                       goto out_dstate;
+               if ((ace->flag & NFS4_INHERITANCE_FLAGS) == 0) {
+                       process_one_v4_ace(&effective_acl_state, ace);
                        continue;
-               case NFS4_INHERITANCE_FLAGS:
-                       /* Add this ace to the default acl and remove it
-                        * from the effective acl: */
-                       error = nfs4_acl_add_ace(dacl, ace->type, ace->flag,
-                               ace->access_mask, ace->whotype, ace->who);
-                       if (error)
-                               return error;
-                       list_del(h);
-                       kfree(ace);
-                       acl->naces--;
-                       break;
-               case NFS4_INHERITANCE_FLAGS & ~NFS4_ACE_INHERIT_ONLY_ACE:
-                       /* Add this ace to the default, but leave it in
-                        * the effective acl as well: */
-                       error = nfs4_acl_add_ace(dacl, ace->type, ace->flag,
-                               ace->access_mask, ace->whotype, ace->who);
-                       if (error)
-                               return error;
-                       break;
-               default:
-                       return -EINVAL;
                }
+               if (!(flags & NFS4_ACL_DIR))
+                       goto out_dstate;
+               /*
+                * Note that when only one of FILE_INHERIT or DIRECTORY_INHERIT
+                * is set, we're effectively turning on the other.  That's OK,
+                * according to rfc 3530.
+                */
+               process_one_v4_ace(&default_acl_state, ace);
+
+               if (!(ace->flag & NFS4_ACE_INHERIT_ONLY_ACE))
+                       process_one_v4_ace(&effective_acl_state, ace);
        }
-       return 0;
+       *pacl = posix_state_to_acl(&effective_acl_state, flags);
+       if (IS_ERR(*pacl)) {
+               ret = PTR_ERR(*pacl);
+               goto out_dstate;
+       }
+       *dpacl = posix_state_to_acl(&default_acl_state,
+                                               flags | NFS4_ACL_TYPE_DEFAULT);
+       if (IS_ERR(*dpacl)) {
+               ret = PTR_ERR(*dpacl);
+               posix_acl_release(*pacl);
+               goto out_dstate;
+       }
+       sort_pacl(*pacl);
+       sort_pacl(*dpacl);
+       ret = 0;
+out_dstate:
+       free_state(&default_acl_state);
+out_estate:
+       free_state(&effective_acl_state);
+       return ret;
 }
 
 static short
@@ -759,48 +774,22 @@ EXPORT_SYMBOL(nfs4_acl_posix_to_nfsv4);
 EXPORT_SYMBOL(nfs4_acl_nfsv4_to_posix);
 
 struct nfs4_acl *
-nfs4_acl_new(void)
+nfs4_acl_new(int n)
 {
        struct nfs4_acl *acl;
 
-       if ((acl = kmalloc(sizeof(*acl), GFP_KERNEL)) == NULL)
+       acl = kmalloc(sizeof(*acl) + n*sizeof(struct nfs4_ace), GFP_KERNEL);
+       if (acl == NULL)
                return NULL;
-
        acl->naces = 0;
-       INIT_LIST_HEAD(&acl->ace_head);
-
        return acl;
 }
 
 void
-nfs4_acl_free(struct nfs4_acl *acl)
-{
-       struct list_head *h;
-       struct nfs4_ace *ace;
-
-       if (!acl)
-               return;
-
-       while (!list_empty(&acl->ace_head)) {
-               h = acl->ace_head.next;
-               list_del(h);
-               ace = list_entry(h, struct nfs4_ace, l_ace);
-               kfree(ace);
-       }
-
-       kfree(acl);
-
-       return;
-}
-
-int
 nfs4_acl_add_ace(struct nfs4_acl *acl, u32 type, u32 flag, u32 access_mask,
                int whotype, uid_t who)
 {
-       struct nfs4_ace *ace;
-
-       if ((ace = kmalloc(sizeof(*ace), GFP_KERNEL)) == NULL)
-               return -ENOMEM;
+       struct nfs4_ace *ace = acl->aces + acl->naces;
 
        ace->type = type;
        ace->flag = flag;
@@ -808,10 +797,7 @@ nfs4_acl_add_ace(struct nfs4_acl *acl, u32 type, u32 flag, u32 access_mask,
        ace->whotype = whotype;
        ace->who = who;
 
-       list_add_tail(&ace->l_ace, &acl->ace_head);
        acl->naces++;
-
-       return 0;
 }
 
 static struct {
@@ -865,7 +851,6 @@ nfs4_acl_write_who(int who, char *p)
 }
 
 EXPORT_SYMBOL(nfs4_acl_new);
-EXPORT_SYMBOL(nfs4_acl_free);
 EXPORT_SYMBOL(nfs4_acl_add_ace);
 EXPORT_SYMBOL(nfs4_acl_get_whotype);
 EXPORT_SYMBOL(nfs4_acl_write_who);