| /* |
| * |
| * (C) COPYRIGHT 2008-2013 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. |
| * |
| */ |
| |
| |
| |
| |
| |
| |
| #include <common/ump_kernel_descriptor_mapping.h> |
| #include <common/ump_kernel_priv.h> |
| |
| #define MALI_PAD_INT(x) (((x) + (BITS_PER_LONG - 1)) & ~(BITS_PER_LONG - 1)) |
| |
| /** |
| * Allocate a descriptor table capable of holding 'count' mappings |
| * @param count Number of mappings in the table |
| * @return Pointer to a new table, NULL on error |
| */ |
| static umpp_descriptor_table * descriptor_table_alloc(unsigned int count); |
| |
| /** |
| * Free a descriptor table |
| * @param table The table to free |
| */ |
| static void descriptor_table_free(umpp_descriptor_table * table); |
| |
| umpp_descriptor_mapping * umpp_descriptor_mapping_create(unsigned int init_entries, unsigned int max_entries) |
| { |
| umpp_descriptor_mapping * map = kzalloc(sizeof(umpp_descriptor_mapping), GFP_KERNEL); |
| |
| init_entries = MALI_PAD_INT(init_entries); |
| max_entries = MALI_PAD_INT(max_entries); |
| |
| if (NULL != map) |
| { |
| map->table = descriptor_table_alloc(init_entries); |
| if (NULL != map->table) |
| { |
| init_rwsem( &map->lock); |
| set_bit(0, map->table->usage); |
| map->max_nr_mappings_allowed = max_entries; |
| map->current_nr_mappings = init_entries; |
| return map; |
| |
| descriptor_table_free(map->table); |
| } |
| kfree(map); |
| } |
| return NULL; |
| } |
| |
| void umpp_descriptor_mapping_destroy(umpp_descriptor_mapping * map) |
| { |
| UMP_ASSERT(NULL != map); |
| descriptor_table_free(map->table); |
| kfree(map); |
| } |
| |
| unsigned int umpp_descriptor_mapping_allocate(umpp_descriptor_mapping * map, void * target) |
| { |
| int descriptor = 0; |
| UMP_ASSERT(NULL != map); |
| down_write( &map->lock); |
| descriptor = find_first_zero_bit(map->table->usage, map->current_nr_mappings); |
| if (descriptor == map->current_nr_mappings) |
| { |
| /* no free descriptor, try to expand the table */ |
| umpp_descriptor_table * new_table; |
| umpp_descriptor_table * old_table = map->table; |
| int nr_mappings_new = map->current_nr_mappings + BITS_PER_LONG; |
| |
| if (map->current_nr_mappings >= map->max_nr_mappings_allowed) |
| { |
| descriptor = 0; |
| goto unlock_and_exit; |
| } |
| |
| new_table = descriptor_table_alloc(nr_mappings_new); |
| if (NULL == new_table) |
| { |
| descriptor = 0; |
| goto unlock_and_exit; |
| } |
| |
| memcpy(new_table->usage, old_table->usage, (sizeof(unsigned long)*map->current_nr_mappings) / BITS_PER_LONG); |
| memcpy(new_table->mappings, old_table->mappings, map->current_nr_mappings * sizeof(void*)); |
| |
| map->table = new_table; |
| map->current_nr_mappings = nr_mappings_new; |
| descriptor_table_free(old_table); |
| } |
| |
| /* we have found a valid descriptor, set the value and usage bit */ |
| set_bit(descriptor, map->table->usage); |
| map->table->mappings[descriptor] = target; |
| |
| unlock_and_exit: |
| up_write(&map->lock); |
| return descriptor; |
| } |
| |
| int umpp_descriptor_mapping_lookup(umpp_descriptor_mapping * map, unsigned int descriptor, void** const target) |
| { |
| int result = -EINVAL; |
| UMP_ASSERT(map); |
| UMP_ASSERT(target); |
| down_read(&map->lock); |
| if ( (descriptor > 0) && (descriptor < map->current_nr_mappings) && test_bit(descriptor, map->table->usage) ) |
| { |
| *target = map->table->mappings[descriptor]; |
| result = 0; |
| } |
| /* keep target untouched if the descriptor was not found */ |
| up_read(&map->lock); |
| return result; |
| } |
| |
| void umpp_descriptor_mapping_remove(umpp_descriptor_mapping * map, unsigned int descriptor) |
| { |
| UMP_ASSERT(map); |
| down_write(&map->lock); |
| if ( (descriptor > 0) && (descriptor < map->current_nr_mappings) && test_bit(descriptor, map->table->usage) ) |
| { |
| map->table->mappings[descriptor] = NULL; |
| clear_bit(descriptor, map->table->usage); |
| } |
| up_write(&map->lock); |
| } |
| |
| static umpp_descriptor_table * descriptor_table_alloc(unsigned int count) |
| { |
| umpp_descriptor_table * table; |
| |
| table = kzalloc(sizeof(umpp_descriptor_table) + ((sizeof(unsigned long) * count)/BITS_PER_LONG) + (sizeof(void*) * count), __GFP_HARDWALL | GFP_KERNEL ); |
| |
| if (NULL != table) |
| { |
| table->usage = (unsigned long*)((u8*)table + sizeof(umpp_descriptor_table)); |
| table->mappings = (void**)((u8*)table + sizeof(umpp_descriptor_table) + ((sizeof(unsigned long) * count)/BITS_PER_LONG)); |
| } |
| |
| return table; |
| } |
| |
| static void descriptor_table_free(umpp_descriptor_table * table) |
| { |
| UMP_ASSERT(table); |
| kfree(table); |
| } |
| |