diff options
author | Paul Mundt <lethal@linux-sh.org> | 2011-01-13 15:06:28 +0900 |
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committer | Paul Mundt <lethal@linux-sh.org> | 2011-01-13 15:06:28 +0900 |
commit | f43dc23d5ea91fca257be02138a255f02d98e806 (patch) | |
tree | b29722f6e965316e90ac97abf79923ced250dc21 /include/linux/flex_array.h | |
parent | f8e53553f452dcbf67cb89c8cba63a1cd6eb4cc0 (diff) | |
parent | 4162cf64973df51fc885825bc9ca4d055891c49f (diff) |
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6 into common/serial-rework
Conflicts:
arch/sh/kernel/cpu/sh2/setup-sh7619.c
arch/sh/kernel/cpu/sh2a/setup-mxg.c
arch/sh/kernel/cpu/sh2a/setup-sh7201.c
arch/sh/kernel/cpu/sh2a/setup-sh7203.c
arch/sh/kernel/cpu/sh2a/setup-sh7206.c
arch/sh/kernel/cpu/sh3/setup-sh7705.c
arch/sh/kernel/cpu/sh3/setup-sh770x.c
arch/sh/kernel/cpu/sh3/setup-sh7710.c
arch/sh/kernel/cpu/sh3/setup-sh7720.c
arch/sh/kernel/cpu/sh4/setup-sh4-202.c
arch/sh/kernel/cpu/sh4/setup-sh7750.c
arch/sh/kernel/cpu/sh4/setup-sh7760.c
arch/sh/kernel/cpu/sh4a/setup-sh7343.c
arch/sh/kernel/cpu/sh4a/setup-sh7366.c
arch/sh/kernel/cpu/sh4a/setup-sh7722.c
arch/sh/kernel/cpu/sh4a/setup-sh7723.c
arch/sh/kernel/cpu/sh4a/setup-sh7724.c
arch/sh/kernel/cpu/sh4a/setup-sh7763.c
arch/sh/kernel/cpu/sh4a/setup-sh7770.c
arch/sh/kernel/cpu/sh4a/setup-sh7780.c
arch/sh/kernel/cpu/sh4a/setup-sh7785.c
arch/sh/kernel/cpu/sh4a/setup-sh7786.c
arch/sh/kernel/cpu/sh4a/setup-shx3.c
arch/sh/kernel/cpu/sh5/setup-sh5.c
drivers/serial/sh-sci.c
drivers/serial/sh-sci.h
include/linux/serial_sci.h
Diffstat (limited to 'include/linux/flex_array.h')
-rw-r--r-- | include/linux/flex_array.h | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/include/linux/flex_array.h b/include/linux/flex_array.h new file mode 100644 index 000000000000..70e4efabe0fb --- /dev/null +++ b/include/linux/flex_array.h @@ -0,0 +1,78 @@ +#ifndef _FLEX_ARRAY_H +#define _FLEX_ARRAY_H + +#include <linux/types.h> +#include <asm/page.h> + +#define FLEX_ARRAY_PART_SIZE PAGE_SIZE +#define FLEX_ARRAY_BASE_SIZE PAGE_SIZE + +struct flex_array_part; + +/* + * This is meant to replace cases where an array-like + * structure has gotten too big to fit into kmalloc() + * and the developer is getting tempted to use + * vmalloc(). + */ + +struct flex_array { + union { + struct { + int element_size; + int total_nr_elements; + struct flex_array_part *parts[]; + }; + /* + * This little trick makes sure that + * sizeof(flex_array) == PAGE_SIZE + */ + char padding[FLEX_ARRAY_BASE_SIZE]; + }; +}; + +/* Number of bytes left in base struct flex_array, excluding metadata */ +#define FLEX_ARRAY_BASE_BYTES_LEFT \ + (FLEX_ARRAY_BASE_SIZE - offsetof(struct flex_array, parts)) + +/* Number of pointers in base to struct flex_array_part pages */ +#define FLEX_ARRAY_NR_BASE_PTRS \ + (FLEX_ARRAY_BASE_BYTES_LEFT / sizeof(struct flex_array_part *)) + +/* Number of elements of size that fit in struct flex_array_part */ +#define FLEX_ARRAY_ELEMENTS_PER_PART(size) \ + (FLEX_ARRAY_PART_SIZE / size) + +/* + * Defines a statically allocated flex array and ensures its parameters are + * valid. + */ +#define DEFINE_FLEX_ARRAY(__arrayname, __element_size, __total) \ + struct flex_array __arrayname = { { { \ + .element_size = (__element_size), \ + .total_nr_elements = (__total), \ + } } }; \ + static inline void __arrayname##_invalid_parameter(void) \ + { \ + BUILD_BUG_ON((__total) > FLEX_ARRAY_NR_BASE_PTRS * \ + FLEX_ARRAY_ELEMENTS_PER_PART(__element_size)); \ + } + +struct flex_array *flex_array_alloc(int element_size, unsigned int total, + gfp_t flags); +int flex_array_prealloc(struct flex_array *fa, unsigned int start, + unsigned int end, gfp_t flags); +void flex_array_free(struct flex_array *fa); +void flex_array_free_parts(struct flex_array *fa); +int flex_array_put(struct flex_array *fa, unsigned int element_nr, void *src, + gfp_t flags); +int flex_array_clear(struct flex_array *fa, unsigned int element_nr); +void *flex_array_get(struct flex_array *fa, unsigned int element_nr); +int flex_array_shrink(struct flex_array *fa); + +#define flex_array_put_ptr(fa, nr, src, gfp) \ + flex_array_put(fa, nr, (void *)&(src), gfp) + +void *flex_array_get_ptr(struct flex_array *fa, unsigned int element_nr); + +#endif /* _FLEX_ARRAY_H */ |