![Philipp Zabel](/assets/img/avatar_default.png)
This patch adds three exported functions to lib/genalloc.c: devm_gen_pool_create, dev_get_gen_pool, and of_get_named_gen_pool. devm_gen_pool_create is a managed version of gen_pool_create that keeps track of the pool via devres and allows the management code to automatically destroy it after device removal. dev_get_gen_pool retrieves the gen_pool for a given device, if it was created with devm_gen_pool_create, using devres_find. of_get_named_gen_pool retrieves the gen_pool for a given device node and property name, where the property must contain a phandle pointing to a platform device node. The corresponding platform device is then fed into dev_get_gen_pool and the resulting gen_pool is returned. [akpm@linux-foundation.org: make the of_get_named_gen_pool() stub static, fixing a zillion link errors] [akpm@linux-foundation.org: squish "struct device declared inside parameter list" warning] Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de> Acked-by: Grant Likely <grant.likely@secretlab.ca> Tested-by: Michal Simek <monstr@monstr.eu> Cc: Fabio Estevam <fabio.estevam@freescale.com> Cc: Matt Porter <mporter@ti.com> Cc: Dong Aisheng <dong.aisheng@linaro.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Rob Herring <rob.herring@calxeda.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Javier Martin <javier.martin@vista-silicon.com> Cc: Huang Shijie <shijie8@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
127 lines
4.4 KiB
C
127 lines
4.4 KiB
C
/*
|
|
* Basic general purpose allocator for managing special purpose
|
|
* memory, for example, memory that is not managed by the regular
|
|
* kmalloc/kfree interface. Uses for this includes on-device special
|
|
* memory, uncached memory etc.
|
|
*
|
|
* It is safe to use the allocator in NMI handlers and other special
|
|
* unblockable contexts that could otherwise deadlock on locks. This
|
|
* is implemented by using atomic operations and retries on any
|
|
* conflicts. The disadvantage is that there may be livelocks in
|
|
* extreme cases. For better scalability, one allocator can be used
|
|
* for each CPU.
|
|
*
|
|
* The lockless operation only works if there is enough memory
|
|
* available. If new memory is added to the pool a lock has to be
|
|
* still taken. So any user relying on locklessness has to ensure
|
|
* that sufficient memory is preallocated.
|
|
*
|
|
* The basic atomic operation of this allocator is cmpxchg on long.
|
|
* On architectures that don't have NMI-safe cmpxchg implementation,
|
|
* the allocator can NOT be used in NMI handler. So code uses the
|
|
* allocator in NMI handler should depend on
|
|
* CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG.
|
|
*
|
|
* This source code is licensed under the GNU General Public License,
|
|
* Version 2. See the file COPYING for more details.
|
|
*/
|
|
|
|
|
|
#ifndef __GENALLOC_H__
|
|
#define __GENALLOC_H__
|
|
|
|
struct device;
|
|
struct device_node;
|
|
|
|
/**
|
|
* Allocation callback function type definition
|
|
* @map: Pointer to bitmap
|
|
* @size: The bitmap size in bits
|
|
* @start: The bitnumber to start searching at
|
|
* @nr: The number of zeroed bits we're looking for
|
|
* @data: optional additional data used by @genpool_algo_t
|
|
*/
|
|
typedef unsigned long (*genpool_algo_t)(unsigned long *map,
|
|
unsigned long size,
|
|
unsigned long start,
|
|
unsigned int nr,
|
|
void *data);
|
|
|
|
/*
|
|
* General purpose special memory pool descriptor.
|
|
*/
|
|
struct gen_pool {
|
|
spinlock_t lock;
|
|
struct list_head chunks; /* list of chunks in this pool */
|
|
int min_alloc_order; /* minimum allocation order */
|
|
|
|
genpool_algo_t algo; /* allocation function */
|
|
void *data;
|
|
};
|
|
|
|
/*
|
|
* General purpose special memory pool chunk descriptor.
|
|
*/
|
|
struct gen_pool_chunk {
|
|
struct list_head next_chunk; /* next chunk in pool */
|
|
atomic_t avail;
|
|
phys_addr_t phys_addr; /* physical starting address of memory chunk */
|
|
unsigned long start_addr; /* starting address of memory chunk */
|
|
unsigned long end_addr; /* ending address of memory chunk */
|
|
unsigned long bits[0]; /* bitmap for allocating memory chunk */
|
|
};
|
|
|
|
extern struct gen_pool *gen_pool_create(int, int);
|
|
extern phys_addr_t gen_pool_virt_to_phys(struct gen_pool *pool, unsigned long);
|
|
extern int gen_pool_add_virt(struct gen_pool *, unsigned long, phys_addr_t,
|
|
size_t, int);
|
|
/**
|
|
* gen_pool_add - add a new chunk of special memory to the pool
|
|
* @pool: pool to add new memory chunk to
|
|
* @addr: starting address of memory chunk to add to pool
|
|
* @size: size in bytes of the memory chunk to add to pool
|
|
* @nid: node id of the node the chunk structure and bitmap should be
|
|
* allocated on, or -1
|
|
*
|
|
* Add a new chunk of special memory to the specified pool.
|
|
*
|
|
* Returns 0 on success or a -ve errno on failure.
|
|
*/
|
|
static inline int gen_pool_add(struct gen_pool *pool, unsigned long addr,
|
|
size_t size, int nid)
|
|
{
|
|
return gen_pool_add_virt(pool, addr, -1, size, nid);
|
|
}
|
|
extern void gen_pool_destroy(struct gen_pool *);
|
|
extern unsigned long gen_pool_alloc(struct gen_pool *, size_t);
|
|
extern void gen_pool_free(struct gen_pool *, unsigned long, size_t);
|
|
extern void gen_pool_for_each_chunk(struct gen_pool *,
|
|
void (*)(struct gen_pool *, struct gen_pool_chunk *, void *), void *);
|
|
extern size_t gen_pool_avail(struct gen_pool *);
|
|
extern size_t gen_pool_size(struct gen_pool *);
|
|
|
|
extern void gen_pool_set_algo(struct gen_pool *pool, genpool_algo_t algo,
|
|
void *data);
|
|
|
|
extern unsigned long gen_pool_first_fit(unsigned long *map, unsigned long size,
|
|
unsigned long start, unsigned int nr, void *data);
|
|
|
|
extern unsigned long gen_pool_best_fit(unsigned long *map, unsigned long size,
|
|
unsigned long start, unsigned int nr, void *data);
|
|
|
|
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);
|
|
|
|
#ifdef CONFIG_OF
|
|
extern struct gen_pool *of_get_named_gen_pool(struct device_node *np,
|
|
const char *propname, int index);
|
|
#else
|
|
static inline struct gen_pool *of_get_named_gen_pool(struct device_node *np,
|
|
const char *propname, int index)
|
|
{
|
|
return NULL;
|
|
}
|
|
#endif
|
|
#endif /* __GENALLOC_H__ */
|