diff options
Diffstat (limited to 'lib/idr.c')
| -rw-r--r-- | lib/idr.c | 55 |
1 files changed, 55 insertions, 0 deletions
@@ -437,6 +437,61 @@ void *idr_find(struct idr *idp, int id) EXPORT_SYMBOL(idr_find); /** + * idr_for_each - iterate through all stored pointers + * @idp: idr handle + * @fn: function to be called for each pointer + * @data: data passed back to callback function + * + * Iterate over the pointers registered with the given idr. The + * callback function will be called for each pointer currently + * registered, passing the id, the pointer and the data pointer passed + * to this function. It is not safe to modify the idr tree while in + * the callback, so functions such as idr_get_new and idr_remove are + * not allowed. + * + * We check the return of @fn each time. If it returns anything other + * than 0, we break out and return that value. + * + * The caller must serialize idr_for_each() vs idr_get_new() and idr_remove(). + */ +int idr_for_each(struct idr *idp, + int (*fn)(int id, void *p, void *data), void *data) +{ + int n, id, max, error = 0; + struct idr_layer *p; + struct idr_layer *pa[MAX_LEVEL]; + struct idr_layer **paa = &pa[0]; + + n = idp->layers * IDR_BITS; + p = idp->top; + max = 1 << n; + + id = 0; + while (id < max) { + while (n > 0 && p) { + n -= IDR_BITS; + *paa++ = p; + p = p->ary[(id >> n) & IDR_MASK]; + } + + if (p) { + error = fn(id, (void *)p, data); + if (error) + break; + } + + id += 1 << n; + while (n < fls(id)) { + n += IDR_BITS; + p = *--paa; + } + } + + return error; +} +EXPORT_SYMBOL(idr_for_each); + +/** * idr_replace - replace pointer for given id * @idp: idr handle * @ptr: pointer you want associated with the id |