/*
* Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
*
- * @APPLE_LICENSE_HEADER_START@
- *
- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License"). You may not use this file except in compliance with the
- * License. Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
- *
- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ *
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
- * License for the specific language governing rights and limitations
- * under the License.
- *
- * @APPLE_LICENSE_HEADER_END@
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/*
* @OSF_COPYRIGHT@
*/
-/*
+/*
* Mach Operating System
* Copyright (c) 1991,1990,1989 Carnegie Mellon University
* All Rights Reserved.
- *
+ *
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
- *
+ *
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
- *
+ *
* Carnegie Mellon requests users of this software to return to
- *
+ *
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
- *
+ *
* any improvements or extensions that they make and grant Carnegie Mellon
* the rights to redistribute these changes.
*/
* tasks' capabilities for ports and port sets.
*/
-#ifndef _IPC_IPC_ENTRY_H_
+#ifndef _IPC_IPC_ENTRY_H_
#define _IPC_IPC_ENTRY_H_
#include <mach/mach_types.h>
* Spaces hold capabilities for ipc_object_t's.
* Each ipc_entry_t records a capability. Most capabilities have
* small names, and the entries are elements of a table.
- * Capabilities can have large names, and a splay tree holds
- * those entries. The cutoff point between the table and the tree
- * is adjusted dynamically to minimize memory consumption.
*
* The ie_index field of entries in the table implements
* a ordered hash table with open addressing and linear probing.
+ *
+ * The ie_dist field holds the distance to the desired spot,
+ * which is used to implement robin-hood hashing.
+ *
* This hash table converts (space, object) -> name.
* It is used independently of the other fields.
*
* It is used as the head of the free list.
*/
+#define IPC_ENTRY_DIST_BITS 12
+#define IPC_ENTRY_DIST_MAX ((1 << IPC_ENTRY_DIST_BITS) - 1)
+#ifdef __LP64__
+#define IPC_ENTRY_INDEX_BITS 32
+#define IPC_ENTRY_INDEX_MAX (UINT32_MAX)
+#else
+#define IPC_ENTRY_INDEX_BITS 20
+#define IPC_ENTRY_INDEX_MAX ((1 << IPC_ENTRY_INDEX_BITS) - 1)
+#endif
+
struct ipc_entry {
- struct ipc_object *ie_object;
- ipc_entry_bits_t ie_bits;
+ struct ipc_object *XNU_PTRAUTH_SIGNED_PTR("ipc_entry.ie_object") ie_object;
+ ipc_entry_bits_t ie_bits;
+ uint32_t ie_dist : IPC_ENTRY_DIST_BITS;
+ mach_port_index_t ie_index : IPC_ENTRY_INDEX_BITS;
union {
- mach_port_index_t next; /* next in freelist, or... */
- ipc_table_index_t request; /* dead name request notify */
+ mach_port_index_t next; /* next in freelist, or... */
+ ipc_table_index_t request; /* dead name request notify */
} index;
- union {
- mach_port_index_t table;
- struct ipc_tree_entry *tree;
- } hash;
};
-#define ie_request index.request
-#define ie_next index.next
-#define ie_index hash.table
+#define ie_request index.request
+#define ie_next index.next
-#define IE_BITS_UREFS_MASK 0x0000ffff /* 16 bits of user-reference */
-#define IE_BITS_UREFS(bits) ((bits) & IE_BITS_UREFS_MASK)
+#define IE_REQ_NONE 0 /* no request */
-#define IE_BITS_TYPE_MASK 0x001f0000 /* 5 bits of capability type */
-#define IE_BITS_TYPE(bits) ((bits) & IE_BITS_TYPE_MASK)
+#define IE_BITS_UREFS_MASK 0x0000ffff /* 16 bits of user-reference */
+#define IE_BITS_UREFS(bits) ((bits) & IE_BITS_UREFS_MASK)
-#define IE_BITS_COLLISION 0x00800000 /* 1 bit for collisions */
+#define IE_BITS_TYPE_MASK 0x001f0000 /* 5 bits of capability type */
+#define IE_BITS_TYPE(bits) ((bits) & IE_BITS_TYPE_MASK)
+#define IE_BITS_EXTYPE_MASK 0x00200000 /* 1 bit for extended capability */
#ifndef NO_PORT_GEN
-#define IE_BITS_GEN_MASK 0xff000000 /* 8 bits for generation */
-#define IE_BITS_GEN(bits) ((bits) & IE_BITS_GEN_MASK)
-#define IE_BITS_GEN_ONE 0x04000000 /* low bit of generation */
-#define IE_BITS_NEW_GEN(old) (((old) + IE_BITS_GEN_ONE) & IE_BITS_GEN_MASK)
-#else
-#define IE_BITS_GEN_MASK 0
-#define IE_BITS_GEN(bits) 0
-#define IE_BITS_GEN_ONE 0
-#define IE_BITS_NEW_GEN(old) (old)
-#endif /* !USE_PORT_GEN */
+#define IE_BITS_GEN_MASK 0xff000000 /* 8 bits for generation */
+#define IE_BITS_GEN(bits) ((bits) & IE_BITS_GEN_MASK)
+#define IE_BITS_GEN_ONE 0x04000000 /* low bit of generation */
+#define IE_BITS_ROLL_POS 22 /* LSB pos of generation rollover */
+#define IE_BITS_ROLL_BITS 2 /* number of generation rollover bits */
+#define IE_BITS_ROLL_MASK (((1 << IE_BITS_ROLL_BITS) - 1) << IE_BITS_ROLL_POS)
+#define IE_BITS_ROLL(bits) ((((bits) & IE_BITS_ROLL_MASK) << 8) ^ IE_BITS_GEN_MASK)
+/*
+ * Restart a generation counter with the specified bits for the rollover point.
+ * There are 4 different rollover points:
+ * bits rollover period
+ * 0 0 64
+ * 0 1 48
+ * 1 0 32
+ * 1 1 16
+ */
+static inline ipc_entry_bits_t
+ipc_entry_new_rollpoint(
+ ipc_entry_bits_t rollbits)
+{
+ rollbits = (rollbits << IE_BITS_ROLL_POS) & IE_BITS_ROLL_MASK;
+ ipc_entry_bits_t newgen = IE_BITS_GEN_MASK + IE_BITS_GEN_ONE;
+ return newgen | rollbits;
+}
-#define IE_BITS_RIGHT_MASK 0x007fffff /* relevant to the right */
+/*
+ * Get the next gencount, modulo the entry's rollover point. If the sum rolls over,
+ * the caller should re-start the generation counter with a different rollpoint.
+ */
+static inline ipc_entry_bits_t
+ipc_entry_new_gen(
+ ipc_entry_bits_t oldgen)
+{
+ ipc_entry_bits_t sum = (oldgen + IE_BITS_GEN_ONE) & IE_BITS_GEN_MASK;
+ ipc_entry_bits_t roll = oldgen & IE_BITS_ROLL_MASK;
+ ipc_entry_bits_t newgen = (sum % IE_BITS_ROLL(oldgen)) | roll;
+ return newgen;
+}
-struct ipc_tree_entry {
- struct ipc_entry ite_entry;
- mach_port_name_t ite_name;
- struct ipc_space *ite_space;
- struct ipc_tree_entry *ite_lchild;
- struct ipc_tree_entry *ite_rchild;
-};
+/* Determine if a gencount has rolled over or not. */
+static inline boolean_t
+ipc_entry_gen_rolled(
+ ipc_entry_bits_t oldgen,
+ ipc_entry_bits_t newgen)
+{
+ return (oldgen & IE_BITS_GEN_MASK) > (newgen & IE_BITS_GEN_MASK);
+}
-#define ite_bits ite_entry.ie_bits
-#define ite_object ite_entry.ie_object
-#define ite_request ite_entry.ie_request
-#define ite_next ite_entry.hash.tree
+#else
+#define IE_BITS_GEN_MASK 0
+#define IE_BITS_GEN(bits) 0
+#define IE_BITS_GEN_ONE 0
+#define IE_BITS_ROLL_POS 0
+#define IE_BITS_ROLL_MASK 0
+#define IE_BITS_ROLL(bits) (bits)
+
+static inline ipc_entry_bits_t
+ipc_entry_new_rollpoint(
+ ipc_entry_bits_t rollbits)
+{
+ return 0;
+}
+
+static inline ipc_entry_bits_t
+ipc_entry_new_gen(
+ ipc_entry_bits_t oldgen)
+{
+ return 0;
+}
-extern zone_t ipc_tree_entry_zone;
+static inline boolean_t
+ipc_entry_gen_rolled(
+ ipc_entry_bits_t oldgen,
+ ipc_entry_bits_t newgen)
+{
+ return FALSE;
+}
-#define ite_alloc() ((ipc_tree_entry_t) zalloc(ipc_tree_entry_zone))
-#define ite_free(ite) zfree(ipc_tree_entry_zone, (ite))
+#endif /* !USE_PORT_GEN */
+#define IE_BITS_RIGHT_MASK 0x007fffff /* relevant to the right */
/*
* Exported interfaces
*/
/* Search for entry in a space by name */
extern ipc_entry_t ipc_entry_lookup(
- ipc_space_t space,
- mach_port_name_t name);
+ ipc_space_t space,
+ mach_port_name_t name);
+
+/* Hold a number of entries in a locked space */
+extern kern_return_t ipc_entries_hold(
+ ipc_space_t space,
+ natural_t count);
+
+/* claim and initialize a held entry in a locked space */
+extern kern_return_t ipc_entry_claim(
+ ipc_space_t space,
+ mach_port_name_t *namep,
+ ipc_entry_t *entryp);
/* Allocate an entry in a space */
extern kern_return_t ipc_entry_get(
- ipc_space_t space,
- mach_port_name_t *namep,
- ipc_entry_t *entryp);
+ ipc_space_t space,
+ mach_port_name_t *namep,
+ ipc_entry_t *entryp);
/* Allocate an entry in a space, growing the space if necessary */
extern kern_return_t ipc_entry_alloc(
- ipc_space_t space,
- mach_port_name_t *namep,
- ipc_entry_t *entryp);
+ ipc_space_t space,
+ mach_port_name_t *namep,
+ ipc_entry_t *entryp);
/* Allocate/find an entry in a space with a specific name */
extern kern_return_t ipc_entry_alloc_name(
- ipc_space_t space,
- mach_port_name_t name,
- ipc_entry_t *entryp);
+ ipc_space_t space,
+ mach_port_name_t name,
+ ipc_entry_t *entryp);
/* Deallocate an entry from a space */
extern void ipc_entry_dealloc(
- ipc_space_t space,
- mach_port_name_t name,
- ipc_entry_t entry);
+ ipc_space_t space,
+ mach_port_name_t name,
+ ipc_entry_t entry);
+
+/* Mark and entry modified in a space */
+extern void ipc_entry_modified(
+ ipc_space_t space,
+ mach_port_name_t name,
+ ipc_entry_t entry);
/* Grow the table in a space */
extern kern_return_t ipc_entry_grow_table(
- ipc_space_t space,
- ipc_table_elems_t target_size);
+ ipc_space_t space,
+ ipc_table_elems_t target_size);
-#endif /* _IPC_IPC_ENTRY_H_ */
+/* mask on/off default entry generation bits */
+extern mach_port_name_t ipc_entry_name_mask(
+ mach_port_name_t name);
+#endif /* _IPC_IPC_ENTRY_H_ */