From 9375db07adeaeea5f5ea7ca0463a8b371d71ddbb Mon Sep 17 00:00:00 2001 From: Philipp Zabel Date: Mon, 29 Apr 2013 16:17:10 -0700 Subject: [PATCH] genalloc: add devres support, allow to find a managed pool by device 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 Acked-by: Grant Likely Tested-by: Michal Simek Cc: Fabio Estevam Cc: Matt Porter Cc: Dong Aisheng Cc: Greg Kroah-Hartman Cc: Rob Herring Cc: Paul Gortmaker Cc: Javier Martin Cc: Huang Shijie Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/genalloc.h | 18 +++++++++ lib/genalloc.c | 81 ++++++++++++++++++++++++++++++++++++++++ 2 files changed, 99 insertions(+) diff --git a/include/linux/genalloc.h b/include/linux/genalloc.h index dd7c569aacad..661d374aeb2d 100644 --- a/include/linux/genalloc.h +++ b/include/linux/genalloc.h @@ -29,6 +29,10 @@ #ifndef __GENALLOC_H__ #define __GENALLOC_H__ + +struct device; +struct device_node; + /** * Allocation callback function type definition * @map: Pointer to bitmap @@ -105,4 +109,18 @@ extern unsigned long gen_pool_first_fit(unsigned long *map, unsigned long size, 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__ */ diff --git a/lib/genalloc.c b/lib/genalloc.c index 54920433705a..b35cfa9bc3d4 100644 --- a/lib/genalloc.c +++ b/lib/genalloc.c @@ -34,6 +34,8 @@ #include #include #include +#include +#include static int set_bits_ll(unsigned long *addr, unsigned long mask_to_set) { @@ -480,3 +482,82 @@ unsigned long gen_pool_best_fit(unsigned long *map, unsigned long size, return start_bit; } EXPORT_SYMBOL(gen_pool_best_fit); + +static void devm_gen_pool_release(struct device *dev, void *res) +{ + gen_pool_destroy(*(struct gen_pool **)res); +} + +/** + * devm_gen_pool_create - managed gen_pool_create + * @dev: device that provides the gen_pool + * @min_alloc_order: log base 2 of number of bytes each bitmap bit represents + * @nid: node id of the node the pool structure should be allocated on, or -1 + * + * Create a new special memory pool that can be used to manage special purpose + * memory not managed by the regular kmalloc/kfree interface. The pool will be + * automatically destroyed by the device management code. + */ +struct gen_pool *devm_gen_pool_create(struct device *dev, int min_alloc_order, + int nid) +{ + struct gen_pool **ptr, *pool; + + ptr = devres_alloc(devm_gen_pool_release, sizeof(*ptr), GFP_KERNEL); + + pool = gen_pool_create(min_alloc_order, nid); + if (pool) { + *ptr = pool; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } + + return pool; +} + +/** + * dev_get_gen_pool - Obtain the gen_pool (if any) for a device + * @dev: device to retrieve the gen_pool from + * @name: Optional name for the gen_pool, usually NULL + * + * Returns the gen_pool for the device if one is present, or NULL. + */ +struct gen_pool *dev_get_gen_pool(struct device *dev) +{ + struct gen_pool **p = devres_find(dev, devm_gen_pool_release, NULL, + NULL); + + if (!p) + return NULL; + return *p; +} +EXPORT_SYMBOL_GPL(dev_get_gen_pool); + +#ifdef CONFIG_OF +/** + * of_get_named_gen_pool - find a pool by phandle property + * @np: device node + * @propname: property name containing phandle(s) + * @index: index into the phandle array + * + * Returns the pool that contains the chunk starting at the physical + * address of the device tree node pointed at by the phandle property, + * or NULL if not found. + */ +struct gen_pool *of_get_named_gen_pool(struct device_node *np, + const char *propname, int index) +{ + struct platform_device *pdev; + struct device_node *np_pool; + + np_pool = of_parse_phandle(np, propname, index); + if (!np_pool) + return NULL; + pdev = of_find_device_by_node(np_pool); + if (!pdev) + return NULL; + return dev_get_gen_pool(&pdev->dev); +} +EXPORT_SYMBOL_GPL(of_get_named_gen_pool); +#endif /* CONFIG_OF */