diff options
| -rw-r--r-- | include/linux/xarray.h | 17 | ||||
| -rw-r--r-- | lib/test_xarray.c | 68 | ||||
| -rw-r--r-- | lib/xarray.c | 61 |
3 files changed, 146 insertions, 0 deletions
diff --git a/include/linux/xarray.h b/include/linux/xarray.h index 381f94a66762..2664e718dbd3 100644 --- a/include/linux/xarray.h +++ b/include/linux/xarray.h @@ -878,6 +878,7 @@ static inline bool xas_retry(struct xa_state *xas, const void *entry) void *xas_load(struct xa_state *); void *xas_store(struct xa_state *, void *entry); void *xas_find(struct xa_state *, unsigned long max); +void *xas_find_conflict(struct xa_state *); bool xas_get_mark(const struct xa_state *, xa_mark_t); void xas_set_mark(const struct xa_state *, xa_mark_t); @@ -1088,6 +1089,22 @@ enum { for (entry = xas_find_marked(xas, max, mark); entry; \ entry = xas_next_marked(xas, max, mark)) +/** + * xas_for_each_conflict() - Iterate over a range of an XArray. + * @xas: XArray operation state. + * @entry: Entry retrieved from the array. + * + * The loop body will be executed for each entry in the XArray that lies + * within the range specified by @xas. If the loop completes successfully, + * any entries that lie in this range will be replaced by @entry. The caller + * may break out of the loop; if they do so, the contents of the XArray will + * be unchanged. The operation may fail due to an out of memory condition. + * The caller may also call xa_set_err() to exit the loop while setting an + * error to record the reason. + */ +#define xas_for_each_conflict(xas, entry) \ + while ((entry = xas_find_conflict(xas))) + void *__xas_next(struct xa_state *); void *__xas_prev(struct xa_state *); diff --git a/lib/test_xarray.c b/lib/test_xarray.c index 85ef1882dd3c..8eba3de1baea 100644 --- a/lib/test_xarray.c +++ b/lib/test_xarray.c @@ -365,6 +365,73 @@ static noinline void check_multi_store(struct xarray *xa) #endif } +static noinline void __check_store_iter(struct xarray *xa, unsigned long start, + unsigned int order, unsigned int present) +{ + XA_STATE_ORDER(xas, xa, start, order); + void *entry; + unsigned int count = 0; + +retry: + xas_lock(&xas); + xas_for_each_conflict(&xas, entry) { + XA_BUG_ON(xa, !xa_is_value(entry)); + XA_BUG_ON(xa, entry < xa_mk_value(start)); + XA_BUG_ON(xa, entry > xa_mk_value(start + (1UL << order) - 1)); + count++; + } + xas_store(&xas, xa_mk_value(start)); + xas_unlock(&xas); + if (xas_nomem(&xas, GFP_KERNEL)) { + count = 0; + goto retry; + } + XA_BUG_ON(xa, xas_error(&xas)); + XA_BUG_ON(xa, count != present); + XA_BUG_ON(xa, xa_load(xa, start) != xa_mk_value(start)); + XA_BUG_ON(xa, xa_load(xa, start + (1UL << order) - 1) != + xa_mk_value(start)); + xa_erase_index(xa, start); +} + +static noinline void check_store_iter(struct xarray *xa) +{ + unsigned int i, j; + unsigned int max_order = IS_ENABLED(CONFIG_XARRAY_MULTI) ? 20 : 1; + + for (i = 0; i < max_order; i++) { + unsigned int min = 1 << i; + unsigned int max = (2 << i) - 1; + __check_store_iter(xa, 0, i, 0); + XA_BUG_ON(xa, !xa_empty(xa)); + __check_store_iter(xa, min, i, 0); + XA_BUG_ON(xa, !xa_empty(xa)); + + xa_store_index(xa, min, GFP_KERNEL); + __check_store_iter(xa, min, i, 1); + XA_BUG_ON(xa, !xa_empty(xa)); + xa_store_index(xa, max, GFP_KERNEL); + __check_store_iter(xa, min, i, 1); + XA_BUG_ON(xa, !xa_empty(xa)); + + for (j = 0; j < min; j++) + xa_store_index(xa, j, GFP_KERNEL); + __check_store_iter(xa, 0, i, min); + XA_BUG_ON(xa, !xa_empty(xa)); + for (j = 0; j < min; j++) + xa_store_index(xa, min + j, GFP_KERNEL); + __check_store_iter(xa, min, i, min); + XA_BUG_ON(xa, !xa_empty(xa)); + } +#ifdef CONFIG_XARRAY_MULTI + xa_store_index(xa, 63, GFP_KERNEL); + xa_store_index(xa, 65, GFP_KERNEL); + __check_store_iter(xa, 64, 2, 1); + xa_erase_index(xa, 63); +#endif + XA_BUG_ON(xa, !xa_empty(xa)); +} + static noinline void check_multi_find(struct xarray *xa) { #ifdef CONFIG_XARRAY_MULTI @@ -627,6 +694,7 @@ static int xarray_checks(void) check_find(&array); check_destroy(&array); check_move(&array); + check_store_iter(&array); printk("XArray: %u of %u tests passed\n", tests_passed, tests_run); return (tests_run == tests_passed) ? 0 : -EINVAL; diff --git a/lib/xarray.c b/lib/xarray.c index 303c46579598..41f8ebc651f5 100644 --- a/lib/xarray.c +++ b/lib/xarray.c @@ -1111,6 +1111,67 @@ max: EXPORT_SYMBOL_GPL(xas_find_marked); /** + * xas_find_conflict() - Find the next present entry in a range. + * @xas: XArray operation state. + * + * The @xas describes both a range and a position within that range. + * + * Context: Any context. Expects xa_lock to be held. + * Return: The next entry in the range covered by @xas or %NULL. + */ +void *xas_find_conflict(struct xa_state *xas) +{ + void *curr; + + if (xas_error(xas)) + return NULL; + + if (!xas->xa_node) + return NULL; + + if (xas_top(xas->xa_node)) { + curr = xas_start(xas); + if (!curr) + return NULL; + while (xa_is_node(curr)) { + struct xa_node *node = xa_to_node(curr); + curr = xas_descend(xas, node); + } + if (curr) + return curr; + } + + if (xas->xa_node->shift > xas->xa_shift) + return NULL; + + for (;;) { + if (xas->xa_node->shift == xas->xa_shift) { + if ((xas->xa_offset & xas->xa_sibs) == xas->xa_sibs) + break; + } else if (xas->xa_offset == XA_CHUNK_MASK) { + xas->xa_offset = xas->xa_node->offset; + xas->xa_node = xa_parent_locked(xas->xa, xas->xa_node); + if (!xas->xa_node) + break; + continue; + } + curr = xa_entry_locked(xas->xa, xas->xa_node, ++xas->xa_offset); + if (xa_is_sibling(curr)) + continue; + while (xa_is_node(curr)) { + xas->xa_node = xa_to_node(curr); + xas->xa_offset = 0; + curr = xa_entry_locked(xas->xa, xas->xa_node, 0); + } + if (curr) + return curr; + } + xas->xa_offset -= xas->xa_sibs; + return NULL; +} +EXPORT_SYMBOL_GPL(xas_find_conflict); + +/** * xa_init_flags() - Initialise an empty XArray with flags. * @xa: XArray. * @flags: XA_FLAG values. |