| Message ID | 1402969165-7526-3-git-send-email-lauraa@codeaurora.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Jun 17, 2014 at 02:39:22AM +0100, Laura Abbott 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. > > Signed-off-by: Laura Abbott <lauraa@codeaurora.org> > --- > include/linux/genalloc.h | 3 +++ > lib/genalloc.c | 29 +++++++++++++++++++++++++++++ > 2 files changed, 32 insertions(+) > > diff --git a/include/linux/genalloc.h b/include/linux/genalloc.h > index 3cd0934..1ccaab4 100644 > --- a/include/linux/genalloc.h > +++ b/include/linux/genalloc.h > @@ -121,6 +121,9 @@ extern struct gen_pool *devm_gen_pool_create(struct device *dev, > int min_alloc_order, int nid); > extern struct gen_pool *dev_get_gen_pool(struct device *dev); > > +bool addr_in_gen_pool(struct gen_pool *pool, unsigned long start, > + size_t size); > + > #ifdef CONFIG_OF > extern struct gen_pool *of_get_named_gen_pool(struct device_node *np, > const char *propname, int index); > diff --git a/lib/genalloc.c b/lib/genalloc.c > index 9758529..66edf93 100644 > --- a/lib/genalloc.c > +++ b/lib/genalloc.c > @@ -403,6 +403,35 @@ void gen_pool_for_each_chunk(struct gen_pool *pool, > EXPORT_SYMBOL(gen_pool_for_each_chunk); > > /** > + * 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. Takes > + * the rcu_read_lock for the duration of the check. > + */ > +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) { Why do you need to check start against the end of the chunk? Is that in case of overflow? Will
On 6/20/2014 2:38 AM, Will Deacon wrote: > On Tue, Jun 17, 2014 at 02:39:22AM +0100, Laura Abbott 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. >> >> Signed-off-by: Laura Abbott <lauraa@codeaurora.org> >> --- >> include/linux/genalloc.h | 3 +++ >> lib/genalloc.c | 29 +++++++++++++++++++++++++++++ >> 2 files changed, 32 insertions(+) >> >> diff --git a/include/linux/genalloc.h b/include/linux/genalloc.h >> index 3cd0934..1ccaab4 100644 >> --- a/include/linux/genalloc.h >> +++ b/include/linux/genalloc.h >> @@ -121,6 +121,9 @@ extern struct gen_pool *devm_gen_pool_create(struct device *dev, >> int min_alloc_order, int nid); >> extern struct gen_pool *dev_get_gen_pool(struct device *dev); >> >> +bool addr_in_gen_pool(struct gen_pool *pool, unsigned long start, >> + size_t size); >> + >> #ifdef CONFIG_OF >> extern struct gen_pool *of_get_named_gen_pool(struct device_node *np, >> const char *propname, int index); >> diff --git a/lib/genalloc.c b/lib/genalloc.c >> index 9758529..66edf93 100644 >> --- a/lib/genalloc.c >> +++ b/lib/genalloc.c >> @@ -403,6 +403,35 @@ void gen_pool_for_each_chunk(struct gen_pool *pool, >> EXPORT_SYMBOL(gen_pool_for_each_chunk); >> >> /** >> + * 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. Takes >> + * the rcu_read_lock for the duration of the check. >> + */ >> +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) { > > Why do you need to check start against the end of the chunk? Is that in case > of overflow? > Yes, this provides an extra check for overflow and also matches similar logic for gen_pool_virt_to_phys. Thanks, Laura
diff --git a/include/linux/genalloc.h b/include/linux/genalloc.h index 3cd0934..1ccaab4 100644 --- a/include/linux/genalloc.h +++ b/include/linux/genalloc.h @@ -121,6 +121,9 @@ extern struct gen_pool *devm_gen_pool_create(struct device *dev, int min_alloc_order, int nid); extern struct gen_pool *dev_get_gen_pool(struct device *dev); +bool addr_in_gen_pool(struct gen_pool *pool, unsigned long start, + size_t size); + #ifdef CONFIG_OF extern struct gen_pool *of_get_named_gen_pool(struct device_node *np, const char *propname, int index); diff --git a/lib/genalloc.c b/lib/genalloc.c index 9758529..66edf93 100644 --- a/lib/genalloc.c +++ b/lib/genalloc.c @@ -403,6 +403,35 @@ void gen_pool_for_each_chunk(struct gen_pool *pool, EXPORT_SYMBOL(gen_pool_for_each_chunk); /** + * 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. Takes + * the rcu_read_lock for the duration of the check. + */ +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; +} + +/** * gen_pool_avail - get available free space of the pool * @pool: pool to get available free space *
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. Signed-off-by: Laura Abbott <lauraa@codeaurora.org> --- include/linux/genalloc.h | 3 +++ lib/genalloc.c | 29 +++++++++++++++++++++++++++++ 2 files changed, 32 insertions(+)