diff options
Diffstat (limited to 'lib/idr.c')
| -rw-r--r-- | lib/idr.c | 35 |
1 files changed, 23 insertions, 12 deletions
diff --git a/lib/idr.c b/lib/idr.c index 282841b5a56..bde6eecb0e8 100644 --- a/lib/idr.c +++ b/lib/idr.c @@ -133,6 +133,21 @@ int idr_pre_get(struct idr *idp, gfp_t gfp_mask) } EXPORT_SYMBOL(idr_pre_get); +/** + * sub_alloc - try to allocate an id without growing the tree depth + * @idp: idr handle + * @starting_id: id to start search at + * @id: pointer to the allocated handle + * @pa: idr_layer[MAX_IDR_LEVEL] used as backtrack buffer + * + * Allocate an id in range [@starting_id, INT_MAX] from @idp without + * growing its depth. Returns + * + * the allocated id >= 0 if successful, + * -EAGAIN if the tree needs to grow for allocation to succeed, + * -ENOSPC if the id space is exhausted, + * -ENOMEM if more idr_layers need to be allocated. + */ static int sub_alloc(struct idr *idp, int *starting_id, struct idr_layer **pa) { int n, m, sh; @@ -161,7 +176,7 @@ static int sub_alloc(struct idr *idp, int *starting_id, struct idr_layer **pa) /* if already at the top layer, we need to grow */ if (id >= 1 << (idp->layers * IDR_BITS)) { *starting_id = id; - return IDR_NEED_TO_GROW; + return -EAGAIN; } p = pa[l]; BUG_ON(!p); @@ -180,7 +195,7 @@ static int sub_alloc(struct idr *idp, int *starting_id, struct idr_layer **pa) id = ((id >> sh) ^ n ^ m) << sh; } if ((id >= MAX_IDR_BIT) || (id < 0)) - return IDR_NOMORE_SPACE; + return -ENOSPC; if (l == 0) break; /* @@ -189,7 +204,7 @@ static int sub_alloc(struct idr *idp, int *starting_id, struct idr_layer **pa) if (!p->ary[m]) { new = get_from_free_list(idp); if (!new) - return -1; + return -ENOMEM; new->layer = l-1; rcu_assign_pointer(p->ary[m], new); p->count++; @@ -215,7 +230,7 @@ build_up: layers = idp->layers; if (unlikely(!p)) { if (!(p = get_from_free_list(idp))) - return -1; + return -ENOMEM; p->layer = 0; layers = 1; } @@ -246,7 +261,7 @@ build_up: __move_to_free_list(idp, new); } spin_unlock_irqrestore(&idp->lock, flags); - return -1; + return -ENOMEM; } new->ary[0] = p; new->count = 1; @@ -258,7 +273,7 @@ build_up: rcu_assign_pointer(idp->top, p); idp->layers = layers; v = sub_alloc(idp, &id, pa); - if (v == IDR_NEED_TO_GROW) + if (v == -EAGAIN) goto build_up; return(v); } @@ -306,12 +321,8 @@ int idr_get_new_above(struct idr *idp, void *ptr, int starting_id, int *id) int rv; rv = idr_get_new_above_int(idp, ptr, starting_id); - /* - * This is a cheap hack until the IDR code can be fixed to - * return proper error values. - */ if (rv < 0) - return _idr_rc_to_errno(rv); + return rv == -ENOMEM ? -EAGAIN : rv; *id = rv; return 0; } @@ -766,7 +777,7 @@ int ida_get_new_above(struct ida *ida, int starting_id, int *p_id) /* get vacant slot */ t = idr_get_empty_slot(&ida->idr, idr_id, pa); if (t < 0) - return _idr_rc_to_errno(t); + return t == -ENOMEM ? -EAGAIN : t; if (t * IDA_BITMAP_BITS >= MAX_IDR_BIT) return -ENOSPC; |