Messages in this thread | | | Date | Fri, 8 Aug 2014 15:40:08 -0700 | From | Andrew Morton <> | Subject | Re: [PATCHv6 2/5] lib/genalloc.c: Add genpool range check function |
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On Fri, 8 Aug 2014 13:23:14 -0700 Laura Abbott <lauraa@codeaurora.org> wrote:
> > After allocating an address from a particular genpool, > there is no good way to verify if that address actually > belongs to a genpool. Introduce addr_in_gen_pool which > will return if an address plus size falls completely > within the genpool range. > > ... > > /** > + * addr_in_gen_pool - checks if an address falls within the range of a pool > + * @pool: the generic memory pool > + * @start: start address > + * @size: size of the region > + * > + * Check if the range of addresses falls within the specified pool.
This description should make it clear that the entire range must be within the pool - that an overlap is "no".
> Takes > + * the rcu_read_lock for the duration of the check.
I don't think this part is worth including.
> + */ > +bool addr_in_gen_pool(struct gen_pool *pool, unsigned long start, > + size_t size) > +{ > + bool found = false; > + unsigned long end = start + size; > + struct gen_pool_chunk *chunk; > + > + rcu_read_lock(); > + list_for_each_entry_rcu(chunk, &(pool)->chunks, next_chunk) { > + if (start >= chunk->start_addr && start <= chunk->end_addr) { > + if (end <= chunk->end_addr) { > + found = true; > + break; > + } > + } > + } > + rcu_read_unlock(); > + return found; > +}
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