diff options
Diffstat (limited to 'lib/flex_array.c')
| -rw-r--r-- | lib/flex_array.c | 48 |
1 files changed, 37 insertions, 11 deletions
diff --git a/lib/flex_array.c b/lib/flex_array.c index c0ea40ba2082..cab7621f98aa 100644 --- a/lib/flex_array.c +++ b/lib/flex_array.c @@ -88,8 +88,11 @@ struct flex_array *flex_array_alloc(int element_size, unsigned int total, gfp_t flags) { struct flex_array *ret; - int max_size = FLEX_ARRAY_NR_BASE_PTRS * - FLEX_ARRAY_ELEMENTS_PER_PART(element_size); + int max_size = 0; + + if (element_size) + max_size = FLEX_ARRAY_NR_BASE_PTRS * + FLEX_ARRAY_ELEMENTS_PER_PART(element_size); /* max_size will end up 0 if element_size > PAGE_SIZE */ if (total > max_size) @@ -183,15 +186,18 @@ __fa_get_part(struct flex_array *fa, int part_nr, gfp_t flags) int flex_array_put(struct flex_array *fa, unsigned int element_nr, void *src, gfp_t flags) { - int part_nr = fa_element_to_part_nr(fa, element_nr); + int part_nr; struct flex_array_part *part; void *dst; if (element_nr >= fa->total_nr_elements) return -ENOSPC; + if (!fa->element_size) + return 0; if (elements_fit_in_base(fa)) part = (struct flex_array_part *)&fa->parts[0]; else { + part_nr = fa_element_to_part_nr(fa, element_nr); part = __fa_get_part(fa, part_nr, flags); if (!part) return -ENOMEM; @@ -211,15 +217,18 @@ EXPORT_SYMBOL(flex_array_put); */ int flex_array_clear(struct flex_array *fa, unsigned int element_nr) { - int part_nr = fa_element_to_part_nr(fa, element_nr); + int part_nr; struct flex_array_part *part; void *dst; if (element_nr >= fa->total_nr_elements) return -ENOSPC; + if (!fa->element_size) + return 0; if (elements_fit_in_base(fa)) part = (struct flex_array_part *)&fa->parts[0]; else { + part_nr = fa_element_to_part_nr(fa, element_nr); part = fa->parts[part_nr]; if (!part) return -EINVAL; @@ -232,10 +241,10 @@ EXPORT_SYMBOL(flex_array_clear); /** * flex_array_prealloc - guarantee that array space exists - * @fa: the flex array for which to preallocate parts - * @start: index of first array element for which space is allocated - * @end: index of last (inclusive) element for which space is allocated - * @flags: page allocation flags + * @fa: the flex array for which to preallocate parts + * @start: index of first array element for which space is allocated + * @nr_elements: number of elements for which space is allocated + * @flags: page allocation flags * * This will guarantee that no future calls to flex_array_put() * will allocate memory. It can be used if you are expecting to @@ -245,15 +254,27 @@ EXPORT_SYMBOL(flex_array_clear); * Locking must be provided by the caller. */ int flex_array_prealloc(struct flex_array *fa, unsigned int start, - unsigned int end, gfp_t flags) + unsigned int nr_elements, gfp_t flags) { int start_part; int end_part; int part_nr; + unsigned int end; struct flex_array_part *part; - if (start >= fa->total_nr_elements || end >= fa->total_nr_elements) + if (!start && !nr_elements) + return 0; + if (start >= fa->total_nr_elements) + return -ENOSPC; + if (!nr_elements) + return 0; + + end = start + nr_elements - 1; + + if (end >= fa->total_nr_elements) return -ENOSPC; + if (!fa->element_size) + return 0; if (elements_fit_in_base(fa)) return 0; start_part = fa_element_to_part_nr(fa, start); @@ -281,14 +302,17 @@ EXPORT_SYMBOL(flex_array_prealloc); */ void *flex_array_get(struct flex_array *fa, unsigned int element_nr) { - int part_nr = fa_element_to_part_nr(fa, element_nr); + int part_nr; struct flex_array_part *part; + if (!fa->element_size) + return NULL; if (element_nr >= fa->total_nr_elements) return NULL; if (elements_fit_in_base(fa)) part = (struct flex_array_part *)&fa->parts[0]; else { + part_nr = fa_element_to_part_nr(fa, element_nr); part = fa->parts[part_nr]; if (!part) return NULL; @@ -343,6 +367,8 @@ int flex_array_shrink(struct flex_array *fa) int part_nr; int ret = 0; + if (!fa->total_nr_elements || !fa->element_size) + return 0; if (elements_fit_in_base(fa)) return ret; for (part_nr = 0; part_nr < FLEX_ARRAY_NR_BASE_PTRS; part_nr++) { |