int check_and_clear_contig_bits(u32 *word, int first, int nbits)
{
for (int i = first; i < first + nbits; i++)
if (check_and_clear_bit(word, i) < 0)
return -1;
return 0;
}
/* Free element at @addr in @cache. Return negative on error. */
int mem_cache_free(struct mem_cache *cache, void *addr)
{
unsigned int struct_addr = (unsigned int)addr;
unsigned int bit;
int err = 0;
/* Check boundary */
if (struct_addr < cache->start || struct_addr > cache->end) {
printf("Error: This address doesn't belong to this cache.\n");
return -1;
}
bit = ((struct_addr - cache->start) / cache->struct_size);
/* Check alignment:
* Find out if there was a lost remainder in last division.
* There shouldn't have been, because addresses are allocated at
* struct_size offsets from cache->start. */
if (((bit * cache->struct_size) + cache->start) != struct_addr) {
printf("Error: This address is not aligned on a predefined "
"structure address in this cache.\n");
err = -1;
return err;
}
/* NOTE: If needed, must lock here */
/* Check free/occupied state */
if (check_and_clear_bit(cache->bitmap, bit) < 0) {
printf("Error: Anomaly in cache occupied state:\n"
"Trying to free already free structure.\n");
err = -1;
goto out;
}
cache->free++;
if (cache->free > cache->total) {
printf("Error: Anomaly in cache occupied state:\n"
"More free elements than total.\n");
err = -1;
goto out;
}
out:
/* NOTE: If locked, must unlock here */
return err;
}
