diff options
Diffstat (limited to 'lib/idr.c')
| -rw-r--r-- | lib/idr.c | 38 |
1 files changed, 23 insertions, 15 deletions
diff --git a/lib/idr.c b/lib/idr.c index 2d016f5c410..63dda62131b 100644 --- a/lib/idr.c +++ b/lib/idr.c @@ -43,6 +43,14 @@ static DEFINE_PER_CPU(struct idr_layer *, idr_preload_head); static DEFINE_PER_CPU(int, idr_preload_cnt); static DEFINE_SPINLOCK(simple_ida_lock); +/* the maximum ID which can be allocated given idr->layers */ +static int idr_max(int layers) +{ + int bits = min_t(int, layers * IDR_BITS, MAX_IDR_SHIFT); + + return (1 << bits) - 1; +} + static struct idr_layer *get_from_free_list(struct idr *idp) { struct idr_layer *p; @@ -290,7 +298,7 @@ build_up: * Add a new layer to the top of the tree if the requested * id is larger than the currently allocated space. */ - while ((layers < (MAX_IDR_LEVEL - 1)) && (id >= (1 << (layers*IDR_BITS)))) { + while (id > idr_max(layers)) { layers++; if (!p->count) { /* special case: if the tree is currently empty, @@ -361,7 +369,7 @@ static void idr_fill_slot(void *ptr, int id, struct idr_layer **pa) */ int idr_get_new_above(struct idr *idp, void *ptr, int starting_id, int *id) { - struct idr_layer *pa[MAX_IDR_LEVEL]; + struct idr_layer *pa[MAX_IDR_LEVEL + 1]; int rv; rv = idr_get_empty_slot(idp, starting_id, pa, 0, idp); @@ -457,7 +465,7 @@ EXPORT_SYMBOL(idr_preload); int idr_alloc(struct idr *idr, void *ptr, int start, int end, gfp_t gfp_mask) { int max = end > 0 ? end - 1 : INT_MAX; /* inclusive upper limit */ - struct idr_layer *pa[MAX_IDR_LEVEL]; + struct idr_layer *pa[MAX_IDR_LEVEL + 1]; int id; might_sleep_if(gfp_mask & __GFP_WAIT); @@ -490,7 +498,7 @@ static void idr_remove_warning(int id) static void sub_remove(struct idr *idp, int shift, int id) { struct idr_layer *p = idp->top; - struct idr_layer **pa[MAX_IDR_LEVEL]; + struct idr_layer **pa[MAX_IDR_LEVEL + 1]; struct idr_layer ***paa = &pa[0]; struct idr_layer *to_free; int n; @@ -571,16 +579,16 @@ void __idr_remove_all(struct idr *idp) int n, id, max; int bt_mask; struct idr_layer *p; - struct idr_layer *pa[MAX_IDR_LEVEL]; + struct idr_layer *pa[MAX_IDR_LEVEL + 1]; struct idr_layer **paa = &pa[0]; n = idp->layers * IDR_BITS; p = idp->top; rcu_assign_pointer(idp->top, NULL); - max = 1 << n; + max = idr_max(idp->layers); id = 0; - while (id < max) { + while (id >= 0 && id <= max) { while (n > IDR_BITS && p) { n -= IDR_BITS; *paa++ = p; @@ -650,7 +658,7 @@ void *idr_find(struct idr *idp, int id) /* Mask off upper bits we don't use for the search. */ id &= MAX_IDR_MASK; - if (id >= (1 << n)) + if (id > idr_max(p->layer + 1)) return NULL; BUG_ON(n == 0); @@ -686,15 +694,15 @@ int idr_for_each(struct idr *idp, { int n, id, max, error = 0; struct idr_layer *p; - struct idr_layer *pa[MAX_IDR_LEVEL]; + struct idr_layer *pa[MAX_IDR_LEVEL + 1]; struct idr_layer **paa = &pa[0]; n = idp->layers * IDR_BITS; p = rcu_dereference_raw(idp->top); - max = 1 << n; + max = idr_max(idp->layers); id = 0; - while (id < max) { + while (id >= 0 && id <= max) { while (n > 0 && p) { n -= IDR_BITS; *paa++ = p; @@ -732,7 +740,7 @@ EXPORT_SYMBOL(idr_for_each); */ void *idr_get_next(struct idr *idp, int *nextidp) { - struct idr_layer *p, *pa[MAX_IDR_LEVEL]; + struct idr_layer *p, *pa[MAX_IDR_LEVEL + 1]; struct idr_layer **paa = &pa[0]; int id = *nextidp; int n, max; @@ -742,9 +750,9 @@ void *idr_get_next(struct idr *idp, int *nextidp) if (!p) return NULL; n = (p->layer + 1) * IDR_BITS; - max = 1 << n; + max = idr_max(p->layer + 1); - while (id < max) { + while (id >= 0 && id <= max) { while (n > 0 && p) { n -= IDR_BITS; *paa++ = p; @@ -918,7 +926,7 @@ EXPORT_SYMBOL(ida_pre_get); */ int ida_get_new_above(struct ida *ida, int starting_id, int *p_id) { - struct idr_layer *pa[MAX_IDR_LEVEL]; + struct idr_layer *pa[MAX_IDR_LEVEL + 1]; struct ida_bitmap *bitmap; unsigned long flags; int idr_id = starting_id / IDA_BITMAP_BITS; |