1 files changed, 111 insertions, 0 deletions

diff --git a/fs/lockd/svcshare.c b/fs/lockd/svcshare.c
new file mode 100644
index 000000000000..4943fb7836ce
--- /dev/null
+++ b/fs/lockd/svcshare.c
@@ -0,0 +1,111 @@
+/*
+ * linux/fs/lockd/svcshare.c
+ *
+ * Management of DOS shares.
+ *
+ * Copyright (C) 1996 Olaf Kirch <okir@monad.swb.de>
+ */
+
+#include <linux/time.h>
+#include <linux/unistd.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+
+#include <linux/sunrpc/clnt.h>
+#include <linux/sunrpc/svc.h>
+#include <linux/lockd/lockd.h>
+#include <linux/lockd/share.h>
+
+static inline int
+nlm_cmp_owner(struct nlm_share *share, struct xdr_netobj *oh)
+{
+        return share->s_owner.len == oh->len
+            && !memcmp(share->s_owner.data, oh->data, oh->len);
+}
+
+u32
+nlmsvc_share_file(struct nlm_host *host, struct nlm_file *file,
+                        struct nlm_args *argp)
+{
+        struct nlm_share        *share;
+        struct xdr_netobj       *oh = &argp->lock.oh;
+        u8                      *ohdata;
+
+        for (share = file->f_shares; share; share = share->s_next) {
+                if (share->s_host == host && nlm_cmp_owner(share, oh))
+                        goto update;
+                if ((argp->fsm_access & share->s_mode)
+                 || (argp->fsm_mode   & share->s_access ))
+                        return nlm_lck_denied;
+        }
+
+        share = (struct nlm_share *) kmalloc(sizeof(*share) + oh->len,
+                                                GFP_KERNEL);
+        if (share == NULL)
+                return nlm_lck_denied_nolocks;
+
+        /* Copy owner handle */
+        ohdata = (u8 *) (share + 1);
+        memcpy(ohdata, oh->data, oh->len);
+
+        share->s_file       = file;
+        share->s_host       = host;
+        share->s_owner.data = ohdata;
+        share->s_owner.len  = oh->len;
+        share->s_next       = file->f_shares;
+        file->f_shares      = share;
+
+update:
+        share->s_access = argp->fsm_access;
+        share->s_mode   = argp->fsm_mode;
+        return nlm_granted;
+}
+
+/*
+ * Delete a share.
+ */
+u32
+nlmsvc_unshare_file(struct nlm_host *host, struct nlm_file *file,
+                        struct nlm_args *argp)
+{
+        struct nlm_share        *share, **shpp;
+        struct xdr_netobj       *oh = &argp->lock.oh;
+
+        for (shpp = &file->f_shares; (share = *shpp) != 0; shpp = &share->s_next) {
+                if (share->s_host == host && nlm_cmp_owner(share, oh)) {
+                        *shpp = share->s_next;
+                        kfree(share);
+                        return nlm_granted;
+                }
+        }
+
+        /* X/Open spec says return success even if there was no
+         * corresponding share. */
+        return nlm_granted;
+}
+
+/*
+ * Traverse all shares for a given file (and host).
+ * NLM_ACT_CHECK is handled by nlmsvc_inspect_file.
+ */
+int
+nlmsvc_traverse_shares(struct nlm_host *host, struct nlm_file *file, int action)
+{
+        struct nlm_share        *share, **shpp;
+
+        shpp = &file->f_shares;
+        while ((share = *shpp) !=  NULL) {
+                if (action == NLM_ACT_MARK)
+                        share->s_host->h_inuse = 1;
+                else if (action == NLM_ACT_UNLOCK) {
+                        if (host == NULL || host == share->s_host) {
+                                *shpp = share->s_next;
+                                kfree(share);
+                                continue;
+                        }
+                }
+                shpp = &share->s_next;
+        }
+
+        return 0;
+}