flex_array: flex_array_prealloc takes a number of elements, not an end
Change flex_array_prealloc to take the number of elements for which space
should be allocated instead of the last (inclusive) element. Users
and documentation are updated accordingly. flex_arrays got introduced before
they had users. When folks started using it, they ended up needing a
different API than was coded up originally. This swaps over to the API that
folks apparently need.
Based-on-patch-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Tested-by: Chris Richards <gizmo@giz-works.com>
Acked-by: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: stable@kernel.org [2.6.38+]
diff --git a/Documentation/flexible-arrays.txt b/Documentation/flexible-arrays.txt
index cb8a3a0..df904ae 100644
--- a/Documentation/flexible-arrays.txt
+++ b/Documentation/flexible-arrays.txt
@@ -66,10 +66,10 @@
entering atomic context, using:
int flex_array_prealloc(struct flex_array *array, unsigned int start,
- unsigned int end, gfp_t flags);
+ unsigned int nr_elements, gfp_t flags);
This function will ensure that memory for the elements indexed in the range
-defined by start and end has been allocated. Thereafter, a
+defined by start and nr_elements has been allocated. Thereafter, a
flex_array_put() call on an element in that range is guaranteed not to
block.
diff --git a/include/linux/flex_array.h b/include/linux/flex_array.h
index 70e4efa..ebeb2f3 100644
--- a/include/linux/flex_array.h
+++ b/include/linux/flex_array.h
@@ -61,7 +61,7 @@
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);
+ unsigned int nr_elements, 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,
diff --git a/lib/flex_array.c b/lib/flex_array.c
index c0ea40b..0c33b24 100644
--- a/lib/flex_array.c
+++ b/lib/flex_array.c
@@ -232,10 +232,10 @@
/**
* 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
@@ -245,13 +245,16 @@
* 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;
+ end = start + nr_elements - 1;
+
if (start >= fa->total_nr_elements || end >= fa->total_nr_elements)
return -ENOSPC;
if (elements_fit_in_base(fa))
diff --git a/security/selinux/ss/policydb.c b/security/selinux/ss/policydb.c
index e7b850a..e6e7ce0 100644
--- a/security/selinux/ss/policydb.c
+++ b/security/selinux/ss/policydb.c
@@ -502,7 +502,7 @@
goto out;
rc = flex_array_prealloc(p->type_val_to_struct_array, 0,
- p->p_types.nprim - 1, GFP_KERNEL | __GFP_ZERO);
+ p->p_types.nprim, GFP_KERNEL | __GFP_ZERO);
if (rc)
goto out;
@@ -519,7 +519,7 @@
goto out;
rc = flex_array_prealloc(p->sym_val_to_name[i],
- 0, p->symtab[i].nprim - 1,
+ 0, p->symtab[i].nprim,
GFP_KERNEL | __GFP_ZERO);
if (rc)
goto out;
@@ -2375,7 +2375,7 @@
goto bad;
/* preallocate so we don't have to worry about the put ever failing */
- rc = flex_array_prealloc(p->type_attr_map_array, 0, p->p_types.nprim - 1,
+ rc = flex_array_prealloc(p->type_attr_map_array, 0, p->p_types.nprim,
GFP_KERNEL | __GFP_ZERO);
if (rc)
goto bad;