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Diffstat (limited to 'drivers/base/ump/src/common/ump_kernel_descriptor_mapping.h')
-rwxr-xr-xdrivers/base/ump/src/common/ump_kernel_descriptor_mapping.h92
1 files changed, 92 insertions, 0 deletions
diff --git a/drivers/base/ump/src/common/ump_kernel_descriptor_mapping.h b/drivers/base/ump/src/common/ump_kernel_descriptor_mapping.h
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+++ b/drivers/base/ump/src/common/ump_kernel_descriptor_mapping.h
@@ -0,0 +1,92 @@
+/*
+ *
+ * (C) COPYRIGHT 2008-2012 ARM Limited. All rights reserved.
+ *
+ * This program is free software and is provided to you under the terms of the
+ * GNU General Public License version 2 as published by the Free Software
+ * Foundation, and any use by you of this program is subject to the terms
+ * of such GNU licence.
+ *
+ * A copy of the licence is included with the program, and can also be obtained
+ * from Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ *
+ */
+
+
+
+/**
+ * @file ump_kernel_descriptor_mapping.h
+ */
+
+#ifndef _UMP_KERNEL_DESCRIPTOR_MAPPING_H_
+#define _UMP_KERNEL_DESCRIPTOR_MAPPING_H_
+
+#include <linux/rwsem.h>
+#include <linux/slab.h>
+/**
+ * The actual descriptor mapping table, never directly accessed by clients
+ */
+typedef struct umpp_descriptor_table
+{
+ /* keep as a unsigned long to rely on the OS's bitops support */
+ unsigned long * usage; /**< Pointer to bitpattern indicating if a descriptor is valid/used(1) or not(0) */
+ void** mappings; /**< Array of the pointers the descriptors map to */
+} umpp_descriptor_table;
+
+/**
+ * The descriptor mapping object
+ * Provides a separate namespace where we can map an integer to a pointer
+ */
+typedef struct umpp_descriptor_mapping
+{
+ struct rw_semaphore lock; /**< Lock protecting access to the mapping object */
+ unsigned int max_nr_mappings_allowed; /**< Max number of mappings to support in this namespace */
+ unsigned int current_nr_mappings; /**< Current number of possible mappings */
+ umpp_descriptor_table * table; /**< Pointer to the current mapping table */
+} umpp_descriptor_mapping;
+
+/**
+ * Create a descriptor mapping object.
+ * Create a descriptor mapping capable of holding init_entries growable to max_entries.
+ * ID 0 is reserved so the number of available entries will be max - 1.
+ * @param init_entries Number of entries to preallocate memory for
+ * @param max_entries Number of entries to max support
+ * @return Pointer to a descriptor mapping object, NULL on failure
+ */
+umpp_descriptor_mapping * umpp_descriptor_mapping_create(unsigned int init_entries, unsigned int max_entries);
+
+/**
+ * Destroy a descriptor mapping object
+ * @param[in] map The map to free
+ */
+void umpp_descriptor_mapping_destroy(umpp_descriptor_mapping * map);
+
+/**
+ * Allocate a new mapping entry (descriptor ID)
+ * Allocates a new entry in the map.
+ * @param[in] map The map to allocate a new entry in
+ * @param[in] target The value to map to
+ * @return The descriptor allocated, ID 0 on failure.
+ */
+unsigned int umpp_descriptor_mapping_allocate(umpp_descriptor_mapping * map, void * target);
+
+/**
+ * Get the value mapped to by a descriptor ID
+ * @param[in] map The map to lookup the descriptor id in
+ * @param[in] descriptor The descriptor ID to lookup
+ * @param[out] target Pointer to a pointer which will receive the stored value
+ *
+ * @return 0 on success lookup, -EINVAL on lookup failure.
+ */
+int umpp_descriptor_mapping_lookup(umpp_descriptor_mapping * map, unsigned int descriptor, void** const target);
+
+/**
+ * Free the descriptor ID
+ * For the descriptor to be reused it has to be freed
+ * @param[in] map The map to free the descriptor from
+ * @param descriptor The descriptor ID to free
+ */
+void umpp_descriptor_mapping_remove(umpp_descriptor_mapping * map, unsigned int descriptor);
+
+#endif /* _UMP_KERNEL_DESCRIPTOR_MAPPING_H_ */