Generic bi-directional map, and related initialisation functions. At the moment

a single map is used to store mappings between sharing handles and disk blocks.
This is used to share pages which store data read of the same blocks on
(virtual) disk.
Note that the map is stored in a shared memory region, as it needs to be
accessed by multiple tapdisk processes. This complicates memory allocation
(malloc cannot be used), prevents poniters to be stored directly (as the shared
memory region might and is mapped at different base address) and finally pthread
locks need to be multi-process aware.

Signed-off-by: Grzegorz Milos <Grzegorz.Milos@citrix.com>

1 files changed, 80 insertions, 0 deletions

diff --git a/tools/memshr/bidir-namedefs.h b/tools/memshr/bidir-namedefs.h
new file mode 100644
index 0000000000..649f063b70
--- /dev/null
+++ b/tools/memshr/bidir-namedefs.h
@@ -0,0 +1,80 @@
+/******************************************************************************
+ *
+ * Copyright (c) 2009 Citrix (R&D) Inc. (Grzegorz Milos)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+#include "memshr-priv.h"
+
+/* Macros used to assemble the names */
+#define BIDIR_NAME_ONE_INTERNAL(prefix, name) \
+                                prefix ## _ ## name
+#define BIDIR_NAME_TWO_INTERNAL(prefix, name1, name2) \
+                                prefix ## _ ## name1 ## _ ## name2
+
+#define BIDIR_NAME_ONE(prefix, name) \
+                                BIDIR_NAME_ONE_INTERNAL(prefix, name)
+#define BIDIR_NAME_TWO(prefix, name1, name2) \
+                                BIDIR_NAME_TWO_INTERNAL(prefix, name1, name2)
+
+#define INTERNAL_NAME_ONE(name) BIDIR_NAME_ONE(BIDIR_NAME_PREFIX, name)
+#define INTERNAL_NAME_TWO(name1, name2) \
+                                BIDIR_NAME_TWO(BIDIR_NAME_PREFIX, name1, name2)
+
+/* Function/type names */
+#define __k_t                   BIDIR_KEY_T
+#define __v_t                   BIDIR_VALUE_T
+
+#define __hash                  INTERNAL_NAME_ONE(hash)
+#define __shm_hash_init         INTERNAL_NAME_ONE(shm_hash_init)
+#define __shm_hash_get          INTERNAL_NAME_ONE(shm_hash_get)
+#define __hash_init             INTERNAL_NAME_ONE(hash_init)
+#define __key_lookup            INTERNAL_NAME_TWO(BIDIR_KEY, lookup)
+#define __value_lookup          INTERNAL_NAME_TWO(BIDIR_VALUE, lookup)
+#define __insert                INTERNAL_NAME_ONE(insert)
+#define __key_remove            INTERNAL_NAME_TWO(BIDIR_KEY, remove)
+#define __value_remove          INTERNAL_NAME_TWO(BIDIR_VALUE, remove)
+#define __hash_destroy          INTERNAL_NAME_ONE(hash_destroy)
+#define __hash_iterator         INTERNAL_NAME_ONE(hash_iterator)
+
+#define __key_hash              INTERNAL_NAME_TWO(BIDIR_KEY, hash)
+#define __key_cmp               INTERNAL_NAME_TWO(BIDIR_KEY, cmp)
+#define __value_hash            INTERNAL_NAME_TWO(BIDIR_VALUE, hash)
+#define __value_cmp             INTERNAL_NAME_TWO(BIDIR_VALUE, cmp)
+
+#define __hash_sizes            INTERNAL_NAME_ONE(hash_sizes)
+
+
+/* Final function exports */
+struct __hash* __shm_hash_init(unsigned long shm_baddr, unsigned long shm_size);
+struct __hash* __shm_hash_get(unsigned long shm_baddr);
+struct __hash *__hash_init   (struct __hash *h, uint32_t min_size);
+int            __key_lookup  (struct __hash *h, __k_t k, __v_t *vp);
+int            __value_lookup(struct __hash *h, __v_t v, __k_t *kp);
+int            __insert      (struct __hash *h, __k_t k, __v_t v);
+int            __key_remove  (struct __hash *h, __k_t k, __v_t *vp);
+int            __value_remove(struct __hash *h, __v_t v, __k_t *kp);
+int            __hash_destroy(struct __hash *h,
+                    void (*entry_consumer)(__k_t k, __v_t v, void *p),
+                    void *d);
+int            __hash_iterator(struct __hash *h,
+                        int (*entry_consumer)(__k_t k, __v_t v, void *p),
+                        void *d);
+void           __hash_sizes(struct __hash *h,
+                            uint32_t *nr_ent,
+                            uint32_t *max_nr_ent,
+                            uint32_t *tab_size,
+                            uint32_t *max_load,
+                            uint32_t *min_load);