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-rw-r--r--lib/idr.c101
1 files changed, 44 insertions, 57 deletions
diff --git a/lib/idr.c b/lib/idr.c
index bfe4db4e165f..e654aebd5f80 100644
--- a/lib/idr.c
+++ b/lib/idr.c
@@ -18,12 +18,6 @@
* pointer or what ever, we treat it as a (void *). You can pass this
* id to a user for him to pass back at a later time. You then pass
* that id to this code and it returns your pointer.
-
- * You can release ids at any time. When all ids are released, most of
- * the memory is returned (we keep MAX_IDR_FREE) in a local pool so we
- * don't need to go to the memory "store" during an id allocate, just
- * so you don't need to be too concerned about locking and conflicts
- * with the slab allocator.
*/
#ifndef TEST // to test in user space...
@@ -151,7 +145,7 @@ static void idr_layer_rcu_free(struct rcu_head *head)
static inline void free_layer(struct idr *idr, struct idr_layer *p)
{
- if (idr->hint && idr->hint == p)
+ if (idr->hint == p)
RCU_INIT_POINTER(idr->hint, NULL);
call_rcu(&p->rcu_head, idr_layer_rcu_free);
}
@@ -196,7 +190,7 @@ static void idr_mark_full(struct idr_layer **pa, int id)
}
}
-int __idr_pre_get(struct idr *idp, gfp_t gfp_mask)
+static int __idr_pre_get(struct idr *idp, gfp_t gfp_mask)
{
while (idp->id_free_cnt < MAX_IDR_FREE) {
struct idr_layer *new;
@@ -207,7 +201,6 @@ int __idr_pre_get(struct idr *idp, gfp_t gfp_mask)
}
return 1;
}
-EXPORT_SYMBOL(__idr_pre_get);
/**
* sub_alloc - try to allocate an id without growing the tree depth
@@ -250,7 +243,7 @@ static int sub_alloc(struct idr *idp, int *starting_id, struct idr_layer **pa,
id = (id | ((1 << (IDR_BITS * l)) - 1)) + 1;
/* if already at the top layer, we need to grow */
- if (id >= 1 << (idp->layers * IDR_BITS)) {
+ if (id > idr_max(idp->layers)) {
*starting_id = id;
return -EAGAIN;
}
@@ -374,20 +367,6 @@ static void idr_fill_slot(struct idr *idr, void *ptr, int id,
idr_mark_full(pa, id);
}
-int __idr_get_new_above(struct idr *idp, void *ptr, int starting_id, int *id)
-{
- struct idr_layer *pa[MAX_IDR_LEVEL + 1];
- int rv;
-
- rv = idr_get_empty_slot(idp, starting_id, pa, 0, idp);
- if (rv < 0)
- return rv == -ENOMEM ? -EAGAIN : rv;
-
- idr_fill_slot(idp, ptr, rv, pa);
- *id = rv;
- return 0;
-}
-EXPORT_SYMBOL(__idr_get_new_above);
/**
* idr_preload - preload for idr_alloc()
@@ -548,7 +527,7 @@ static void sub_remove(struct idr *idp, int shift, int id)
n = id & IDR_MASK;
if (likely(p != NULL && test_bit(n, p->bitmap))) {
__clear_bit(n, p->bitmap);
- rcu_assign_pointer(p->ary[n], NULL);
+ RCU_INIT_POINTER(p->ary[n], NULL);
to_free = NULL;
while(*paa && ! --((**paa)->count)){
if (to_free)
@@ -577,6 +556,11 @@ void idr_remove(struct idr *idp, int id)
if (id < 0)
return;
+ if (id > idr_max(idp->layers)) {
+ idr_remove_warning(id);
+ return;
+ }
+
sub_remove(idp, (idp->layers - 1) * IDR_BITS, id);
if (idp->top && idp->top->count == 1 && (idp->layers > 1) &&
idp->top->ary[0]) {
@@ -594,20 +578,10 @@ void idr_remove(struct idr *idp, int id)
bitmap_clear(to_free->bitmap, 0, IDR_SIZE);
free_layer(idp, to_free);
}
- while (idp->id_free_cnt >= MAX_IDR_FREE) {
- p = get_from_free_list(idp);
- /*
- * Note: we don't call the rcu callback here, since the only
- * layers that fall into the freelist are those that have been
- * preallocated.
- */
- kmem_cache_free(idr_layer_cache, p);
- }
- return;
}
EXPORT_SYMBOL(idr_remove);
-void __idr_remove_all(struct idr *idp)
+static void __idr_remove_all(struct idr *idp)
{
int n, id, max;
int bt_mask;
@@ -616,31 +590,31 @@ void __idr_remove_all(struct idr *idp)
struct idr_layer **paa = &pa[0];
n = idp->layers * IDR_BITS;
- p = idp->top;
- rcu_assign_pointer(idp->top, NULL);
+ *paa = idp->top;
+ RCU_INIT_POINTER(idp->top, NULL);
max = idr_max(idp->layers);
id = 0;
while (id >= 0 && id <= max) {
+ p = *paa;
while (n > IDR_BITS && p) {
n -= IDR_BITS;
- *paa++ = p;
p = p->ary[(id >> n) & IDR_MASK];
+ *++paa = p;
}
bt_mask = id;
id += 1 << n;
/* Get the highest bit that the above add changed from 0->1. */
while (n < fls(id ^ bt_mask)) {
- if (p)
- free_layer(idp, p);
+ if (*paa)
+ free_layer(idp, *paa);
n += IDR_BITS;
- p = *--paa;
+ --paa;
}
}
idp->layers = 0;
}
-EXPORT_SYMBOL(__idr_remove_all);
/**
* idr_destroy - release all cached layers within an idr tree
@@ -652,7 +626,7 @@ EXPORT_SYMBOL(__idr_remove_all);
* idr_destroy().
*
* A typical clean-up sequence for objects stored in an idr tree will use
- * idr_for_each() to free all objects, if necessay, then idr_destroy() to
+ * idr_for_each() to free all objects, if necessary, then idr_destroy() to
* free up the id mappings and cached idr_layers.
*/
void idr_destroy(struct idr *idp)
@@ -719,15 +693,16 @@ int idr_for_each(struct idr *idp,
struct idr_layer **paa = &pa[0];
n = idp->layers * IDR_BITS;
- p = rcu_dereference_raw(idp->top);
+ *paa = rcu_dereference_raw(idp->top);
max = idr_max(idp->layers);
id = 0;
while (id >= 0 && id <= max) {
+ p = *paa;
while (n > 0 && p) {
n -= IDR_BITS;
- *paa++ = p;
p = rcu_dereference_raw(p->ary[(id >> n) & IDR_MASK]);
+ *++paa = p;
}
if (p) {
@@ -739,7 +714,7 @@ int idr_for_each(struct idr *idp,
id += 1 << n;
while (n < fls(id)) {
n += IDR_BITS;
- p = *--paa;
+ --paa;
}
}
@@ -767,17 +742,18 @@ void *idr_get_next(struct idr *idp, int *nextidp)
int n, max;
/* find first ent */
- p = rcu_dereference_raw(idp->top);
+ p = *paa = rcu_dereference_raw(idp->top);
if (!p)
return NULL;
n = (p->layer + 1) * IDR_BITS;
max = idr_max(p->layer + 1);
while (id >= 0 && id <= max) {
+ p = *paa;
while (n > 0 && p) {
n -= IDR_BITS;
- *paa++ = p;
p = rcu_dereference_raw(p->ary[(id >> n) & IDR_MASK]);
+ *++paa = p;
}
if (p) {
@@ -795,7 +771,7 @@ void *idr_get_next(struct idr *idp, int *nextidp)
id = round_up(id + 1, 1 << n);
while (n < fls(id)) {
n += IDR_BITS;
- p = *--paa;
+ --paa;
}
}
return NULL;
@@ -825,14 +801,12 @@ void *idr_replace(struct idr *idp, void *ptr, int id)
p = idp->top;
if (!p)
- return ERR_PTR(-EINVAL);
-
- n = (p->layer+1) * IDR_BITS;
+ return ERR_PTR(-ENOENT);
- if (id >= (1 << n))
- return ERR_PTR(-EINVAL);
+ if (id > idr_max(p->layer + 1))
+ return ERR_PTR(-ENOENT);
- n -= IDR_BITS;
+ n = p->layer * IDR_BITS;
while ((n > 0) && p) {
p = p->ary[(id >> n) & IDR_MASK];
n -= IDR_BITS;
@@ -869,6 +843,16 @@ void idr_init(struct idr *idp)
}
EXPORT_SYMBOL(idr_init);
+static int idr_has_entry(int id, void *p, void *data)
+{
+ return 1;
+}
+
+bool idr_is_empty(struct idr *idp)
+{
+ return !idr_for_each(idp, idr_has_entry, NULL);
+}
+EXPORT_SYMBOL(idr_is_empty);
/**
* DOC: IDA description
@@ -1033,6 +1017,9 @@ void ida_remove(struct ida *ida, int id)
int n;
struct ida_bitmap *bitmap;
+ if (idr_id > idr_max(ida->idr.layers))
+ goto err;
+
/* clear full bits while looking up the leaf idr_layer */
while ((shift > 0) && p) {
n = (idr_id >> shift) & IDR_MASK;
@@ -1048,7 +1035,7 @@ void ida_remove(struct ida *ida, int id)
__clear_bit(n, p->bitmap);
bitmap = (void *)p->ary[n];
- if (!test_bit(offset, bitmap->bitmap))
+ if (!bitmap || !test_bit(offset, bitmap->bitmap))
goto err;
/* update bitmap and remove it if empty */
generated by cgit v1.2.3 (git 2.25.1) at 2025-12-12 03:47:20 +0000