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Regard whitespace Rev 3390 → Rev 3391

/drivers/ddk/linux/idr.c
20,7 → 20,7
* 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 IDR_FREE_MAX) in a local pool so we
* 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.
27,96 → 27,99
*/
 
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/string.h>
#include <linux/bitops.h>
#include <linux/idr.h>
//#include <stdlib.h>
 
unsigned long find_first_bit(const unsigned long *addr, unsigned long size)
{
const unsigned long *p = addr;
unsigned long result = 0;
unsigned long tmp;
unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size,
unsigned long offset);
 
while (size & ~(BITS_PER_LONG-1)) {
if ((tmp = *(p++)))
goto found;
result += BITS_PER_LONG;
size -= BITS_PER_LONG;
}
if (!size)
return result;
 
tmp = (*p) & (~0UL >> (BITS_PER_LONG - size));
if (tmp == 0UL) /* Are any bits set? */
return result + size; /* Nope. */
found:
return result + __ffs(tmp);
}
#define MAX_IDR_SHIFT (sizeof(int) * 8 - 1)
#define MAX_IDR_BIT (1U << MAX_IDR_SHIFT)
 
int find_next_bit(const unsigned long *addr, int size, int offset)
/* Leave the possibility of an incomplete final layer */
#define MAX_IDR_LEVEL ((MAX_IDR_SHIFT + IDR_BITS - 1) / IDR_BITS)
 
/* Number of id_layer structs to leave in free list */
#define MAX_IDR_FREE (MAX_IDR_LEVEL * 2)
 
static struct idr_layer *idr_preload_head;
static int idr_preload_cnt;
 
 
/* the maximum ID which can be allocated given idr->layers */
static int idr_max(int layers)
{
const unsigned long *p = addr + (offset >> 5);
int set = 0, bit = offset & 31, res;
int bits = min_t(int, layers * IDR_BITS, MAX_IDR_SHIFT);
 
if (bit)
{
/*
* Look for nonzero in the first 32 bits:
*/
__asm__("bsfl %1,%0\n\t"
"jne 1f\n\t"
"movl $32, %0\n"
"1:"
: "=r" (set)
: "r" (*p >> bit));
if (set < (32 - bit))
return set + offset;
set = 32 - bit;
p++;
return (1 << bits) - 1;
}
 
/*
* No set bit yet, search remaining full words for a bit
* Prefix mask for an idr_layer at @layer. For layer 0, the prefix mask is
* all bits except for the lower IDR_BITS. For layer 1, 2 * IDR_BITS, and
* so on.
*/
res = find_first_bit (p, size - 32 * (p - addr));
return (offset + set + res);
static int idr_layer_prefix_mask(int layer)
{
return ~idr_max(layer + 1);
}
 
#define ACCESS_ONCE(x) (*(volatile typeof(x) *)&(x))
 
#define rcu_dereference(p) ({ \
typeof(p) _________p1 = ACCESS_ONCE(p); \
(_________p1); \
})
 
#define rcu_assign_pointer(p, v) \
({ \
if (!__builtin_constant_p(v) || \
((v) != NULL)) \
(p) = (v); \
})
 
//static struct kmem_cache *idr_layer_cache;
 
 
 
 
 
static struct idr_layer *get_from_free_list(struct idr *idp)
{
struct idr_layer *p;
unsigned long flags;
 
// spin_lock_irqsave(&idp->lock, flags);
spin_lock_irqsave(&idp->lock, flags);
if ((p = idp->id_free)) {
idp->id_free = p->ary[0];
idp->id_free_cnt--;
p->ary[0] = NULL;
}
// spin_unlock_irqrestore(&idp->lock, flags);
spin_unlock_irqrestore(&idp->lock, flags);
return(p);
}
 
/**
* idr_layer_alloc - allocate a new idr_layer
* @gfp_mask: allocation mask
* @layer_idr: optional idr to allocate from
*
* If @layer_idr is %NULL, directly allocate one using @gfp_mask or fetch
* one from the per-cpu preload buffer. If @layer_idr is not %NULL, fetch
* an idr_layer from @idr->id_free.
*
* @layer_idr is to maintain backward compatibility with the old alloc
* interface - idr_pre_get() and idr_get_new*() - and will be removed
* together with per-pool preload buffer.
*/
static struct idr_layer *idr_layer_alloc(gfp_t gfp_mask, struct idr *layer_idr)
{
struct idr_layer *new;
 
/* this is the old path, bypass to get_from_free_list() */
if (layer_idr)
return get_from_free_list(layer_idr);
 
/* try to allocate directly from kmem_cache */
new = kzalloc(sizeof(struct idr_layer), gfp_mask);
if (new)
return new;
 
 
new = idr_preload_head;
if (new) {
idr_preload_head = new->ary[0];
idr_preload_cnt--;
new->ary[0] = NULL;
}
preempt_enable();
return new;
}
 
static void idr_layer_rcu_free(struct rcu_head *head)
{
struct idr_layer *layer;
125,9 → 128,11
kfree(layer);
}
 
static inline void free_layer(struct idr_layer *p)
static inline void free_layer(struct idr *idr, struct idr_layer *p)
{
kfree(p);
if (idr->hint && idr->hint == p)
RCU_INIT_POINTER(idr->hint, NULL);
idr_layer_rcu_free(&p->rcu_head);
}
 
/* only called when idp->lock is held */
145,9 → 150,9
/*
* Depends on the return element being zeroed.
*/
// spin_lock_irqsave(&idp->lock, flags);
spin_lock_irqsave(&idp->lock, flags);
__move_to_free_list(idp, p);
// spin_unlock_irqrestore(&idp->lock, flags);
spin_unlock_irqrestore(&idp->lock, flags);
}
 
static void idr_mark_full(struct idr_layer **pa, int id)
155,7 → 160,7
struct idr_layer *p = pa[0];
int l = 0;
 
__set_bit(id & IDR_MASK, &p->bitmap);
__set_bit(id & IDR_MASK, p->bitmap);
/*
* If this layer is full mark the bit in the layer above to
* show that this part of the radix tree is full. This may
162,11 → 167,11
* complete the layer above and require walking up the radix
* tree.
*/
while (p->bitmap == IDR_FULL) {
while (bitmap_full(p->bitmap, IDR_SIZE)) {
if (!(p = pa[++l]))
break;
id = id >> IDR_BITS;
__set_bit((id & IDR_MASK), &p->bitmap);
__set_bit((id & IDR_MASK), p->bitmap);
}
}
 
185,7 → 190,7
*/
int idr_pre_get(struct idr *idp, gfp_t gfp_mask)
{
while (idp->id_free_cnt < IDR_FREE_MAX) {
while (idp->id_free_cnt < MAX_IDR_FREE) {
struct idr_layer *new;
new = kzalloc(sizeof(struct idr_layer), gfp_mask);
if (new == NULL)
194,13 → 199,31
}
return 1;
}
EXPORT_SYMBOL(idr_pre_get);
 
static int sub_alloc(struct idr *idp, int *starting_id, struct idr_layer **pa)
/**
* 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
* @gfp_mask: allocation mask for idr_layer_alloc()
* @layer_idr: optional idr passed to idr_layer_alloc()
*
* 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,
gfp_t gfp_mask, struct idr *layer_idr)
{
int n, m, sh;
struct idr_layer *p, *new;
int l, id, oid;
unsigned long bm;
 
id = *starting_id;
restart:
212,8 → 235,7
* We run around this while until we reach the leaf node...
*/
n = (id >> (IDR_BITS*l)) & IDR_MASK;
bm = ~p->bitmap;
m = find_next_bit(&bm, IDR_SIZE, n);
m = find_next_zero_bit(p->bitmap, IDR_SIZE, n);
if (m == IDR_SIZE) {
/* no space available go back to previous layer. */
l++;
221,10 → 243,12
id = (id | ((1 << (IDR_BITS * l)) - 1)) + 1;
 
/* if already at the top layer, we need to grow */
if (!(p = pa[l])) {
if (id >= 1 << (idp->layers * IDR_BITS)) {
*starting_id = id;
return IDR_NEED_TO_GROW;
return -EAGAIN;
}
p = pa[l];
BUG_ON(!p);
 
/* If we need to go up one layer, continue the
* loop; otherwise, restart from the top.
239,8 → 263,8
sh = IDR_BITS*l;
id = ((id >> sh) ^ n ^ m) << sh;
}
if ((id >= MAX_ID_BIT) || (id < 0))
return IDR_NOMORE_SPACE;
if ((id >= MAX_IDR_BIT) || (id < 0))
return -ENOSPC;
if (l == 0)
break;
/*
247,10 → 271,11
* Create the layer below if it is missing.
*/
if (!p->ary[m]) {
new = get_from_free_list(idp);
new = idr_layer_alloc(gfp_mask, layer_idr);
if (!new)
return -1;
return -ENOMEM;
new->layer = l-1;
new->prefix = id & idr_layer_prefix_mask(new->layer);
rcu_assign_pointer(p->ary[m], new);
p->count++;
}
263,7 → 288,8
}
 
static int idr_get_empty_slot(struct idr *idp, int starting_id,
struct idr_layer **pa)
struct idr_layer **pa, gfp_t gfp_mask,
struct idr *layer_idr)
{
struct idr_layer *p, *new;
int layers, v, id;
274,8 → 300,8
p = idp->top;
layers = idp->layers;
if (unlikely(!p)) {
if (!(p = get_from_free_list(idp)))
return -1;
if (!(p = idr_layer_alloc(gfp_mask, layer_idr)))
return -ENOMEM;
p->layer = 0;
layers = 1;
}
283,7 → 309,7
* Add a new layer to the top of the tree if the requested
* id is larger than the currently allocated space.
*/
while ((layers < (MAX_LEVEL - 1)) && (id >= (1 << (layers*IDR_BITS)))) {
while (id > idr_max(layers)) {
layers++;
if (!p->count) {
/* special case: if the tree is currently empty,
291,58 → 317,56
* upwards.
*/
p->layer++;
WARN_ON_ONCE(p->prefix);
continue;
}
if (!(new = get_from_free_list(idp))) {
if (!(new = idr_layer_alloc(gfp_mask, layer_idr))) {
/*
* The allocation failed. If we built part of
* the structure tear it down.
*/
// spin_lock_irqsave(&idp->lock, flags);
spin_lock_irqsave(&idp->lock, flags);
for (new = p; p && p != idp->top; new = p) {
p = p->ary[0];
new->ary[0] = NULL;
new->bitmap = new->count = 0;
new->count = 0;
bitmap_clear(new->bitmap, 0, IDR_SIZE);
__move_to_free_list(idp, new);
}
// spin_unlock_irqrestore(&idp->lock, flags);
return -1;
spin_unlock_irqrestore(&idp->lock, flags);
return -ENOMEM;
}
new->ary[0] = p;
new->count = 1;
new->layer = layers-1;
if (p->bitmap == IDR_FULL)
__set_bit(0, &new->bitmap);
new->prefix = id & idr_layer_prefix_mask(new->layer);
if (bitmap_full(p->bitmap, IDR_SIZE))
__set_bit(0, new->bitmap);
p = new;
}
rcu_assign_pointer(idp->top, p);
idp->layers = layers;
v = sub_alloc(idp, &id, pa);
if (v == IDR_NEED_TO_GROW)
v = sub_alloc(idp, &id, pa, gfp_mask, layer_idr);
if (v == -EAGAIN)
goto build_up;
return(v);
}
 
static int idr_get_new_above_int(struct idr *idp, void *ptr, int starting_id)
/*
* @id and @pa are from a successful allocation from idr_get_empty_slot().
* Install the user pointer @ptr and mark the slot full.
*/
static void idr_fill_slot(struct idr *idr, void *ptr, int id,
struct idr_layer **pa)
{
struct idr_layer *pa[MAX_LEVEL];
int id;
/* update hint used for lookup, cleared from free_layer() */
rcu_assign_pointer(idr->hint, pa[0]);
 
id = idr_get_empty_slot(idp, starting_id, pa);
if (id >= 0) {
/*
* Successfully found an empty slot. Install the user
* pointer and mark the slot full.
*/
rcu_assign_pointer(pa[0]->ary[id & IDR_MASK],
(struct idr_layer *)ptr);
rcu_assign_pointer(pa[0]->ary[id & IDR_MASK], (struct idr_layer *)ptr);
pa[0]->count++;
idr_mark_full(pa, id);
}
 
return id;
}
 
/**
* idr_get_new_above - allocate new idr entry above or equal to a start id
* @idp: idr handle
363,51 → 387,113
*/
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_new_above_int(idp, ptr, starting_id);
/*
* This is a cheap hack until the IDR code can be fixed to
* return proper error values.
*/
rv = idr_get_empty_slot(idp, starting_id, pa, 0, idp);
if (rv < 0)
{
dbgprintf("fail\n");
return _idr_rc_to_errno(rv);
};
return rv == -ENOMEM ? -EAGAIN : rv;
 
idr_fill_slot(idp, ptr, rv, pa);
*id = rv;
return 0;
}
EXPORT_SYMBOL(idr_get_new_above);
 
/**
* idr_get_new - allocate new idr entry
* @idp: idr handle
* @ptr: pointer you want associated with the id
* @id: pointer to the allocated handle
* idr_preload - preload for idr_alloc()
* @gfp_mask: allocation mask to use for preloading
*
* If allocation from IDR's private freelist fails, idr_get_new_above() will
* return %-EAGAIN. The caller should retry the idr_pre_get() call to refill
* IDR's preallocation and then retry the idr_get_new_above() call.
* Preload per-cpu layer buffer for idr_alloc(). Can only be used from
* process context and each idr_preload() invocation should be matched with
* idr_preload_end(). Note that preemption is disabled while preloaded.
*
* If the idr is full idr_get_new_above() will return %-ENOSPC.
* The first idr_alloc() in the preloaded section can be treated as if it
* were invoked with @gfp_mask used for preloading. This allows using more
* permissive allocation masks for idrs protected by spinlocks.
*
* @id returns a value in the range %0 ... %0x7fffffff
* For example, if idr_alloc() below fails, the failure can be treated as
* if idr_alloc() were called with GFP_KERNEL rather than GFP_NOWAIT.
*
* idr_preload(GFP_KERNEL);
* spin_lock(lock);
*
* id = idr_alloc(idr, ptr, start, end, GFP_NOWAIT);
*
* spin_unlock(lock);
* idr_preload_end();
* if (id < 0)
* error;
*/
int idr_get_new(struct idr *idp, void *ptr, int *id)
void idr_preload(gfp_t gfp_mask)
{
int rv;
 
rv = idr_get_new_above_int(idp, ptr, 0);
/*
* This is a cheap hack until the IDR code can be fixed to
* return proper error values.
* idr_alloc() is likely to succeed w/o full idr_layer buffer and
* return value from idr_alloc() needs to be checked for failure
* anyway. Silently give up if allocation fails. The caller can
* treat failures from idr_alloc() as if idr_alloc() were called
* with @gfp_mask which should be enough.
*/
if (rv < 0)
return _idr_rc_to_errno(rv);
*id = rv;
return 0;
while (idr_preload_cnt < MAX_IDR_FREE) {
struct idr_layer *new;
 
new = kzalloc(sizeof(struct idr_layer), gfp_mask);
if (!new)
break;
 
/* link the new one to per-cpu preload list */
new->ary[0] = idr_preload_head;
idr_preload_head = new;
idr_preload_cnt++;
}
}
EXPORT_SYMBOL(idr_preload);
 
/**
* idr_alloc - allocate new idr entry
* @idr: the (initialized) idr
* @ptr: pointer to be associated with the new id
* @start: the minimum id (inclusive)
* @end: the maximum id (exclusive, <= 0 for max)
* @gfp_mask: memory allocation flags
*
* Allocate an id in [start, end) and associate it with @ptr. If no ID is
* available in the specified range, returns -ENOSPC. On memory allocation
* failure, returns -ENOMEM.
*
* Note that @end is treated as max when <= 0. This is to always allow
* using @start + N as @end as long as N is inside integer range.
*
* The user is responsible for exclusively synchronizing all operations
* which may modify @idr. However, read-only accesses such as idr_find()
* or iteration can be performed under RCU read lock provided the user
* destroys @ptr in RCU-safe way after removal from idr.
*/
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 + 1];
int id;
 
/* sanity checks */
if (WARN_ON_ONCE(start < 0))
return -EINVAL;
if (unlikely(max < start))
return -ENOSPC;
 
/* allocate id */
id = idr_get_empty_slot(idr, start, pa, gfp_mask, NULL);
if (unlikely(id < 0))
return id;
if (unlikely(id > max))
return -ENOSPC;
 
idr_fill_slot(idr, ptr, id, pa);
return id;
}
EXPORT_SYMBOL_GPL(idr_alloc);
 
static void idr_remove_warning(int id)
{
printk(KERN_WARNING
418,7 → 504,7
static void sub_remove(struct idr *idp, int shift, int id)
{
struct idr_layer *p = idp->top;
struct idr_layer **pa[MAX_LEVEL];
struct idr_layer **pa[MAX_IDR_LEVEL + 1];
struct idr_layer ***paa = &pa[0];
struct idr_layer *to_free;
int n;
428,19 → 514,19
 
while ((shift > 0) && p) {
n = (id >> shift) & IDR_MASK;
__clear_bit(n, &p->bitmap);
__clear_bit(n, p->bitmap);
*++paa = &p->ary[n];
p = p->ary[n];
shift -= IDR_BITS;
}
n = id & IDR_MASK;
if (likely(p != NULL && test_bit(n, &p->bitmap))){
__clear_bit(n, &p->bitmap);
if (likely(p != NULL && test_bit(n, p->bitmap))) {
__clear_bit(n, p->bitmap);
rcu_assign_pointer(p->ary[n], NULL);
to_free = NULL;
while(*paa && ! --((**paa)->count)){
if (to_free)
free_layer(to_free);
free_layer(idp, to_free);
to_free = **paa;
**paa-- = NULL;
}
447,7 → 533,7
if (!*paa)
idp->layers = 0;
if (to_free)
free_layer(to_free);
free_layer(idp, to_free);
} else
idr_remove_warning(id);
}
462,8 → 548,9
struct idr_layer *p;
struct idr_layer *to_free;
 
/* Mask off upper bits we don't use for the search. */
id &= MAX_ID_MASK;
/* see comment in idr_find_slowpath() */
if (WARN_ON_ONCE(id < 0))
return;
 
sub_remove(idp, (idp->layers - 1) * IDR_BITS, id);
if (idp->top && idp->top->count == 1 && (idp->layers > 1) &&
478,10 → 565,11
p = idp->top->ary[0];
rcu_assign_pointer(idp->top, p);
--idp->layers;
to_free->bitmap = to_free->count = 0;
free_layer(to_free);
to_free->count = 0;
bitmap_clear(to_free->bitmap, 0, IDR_SIZE);
free_layer(idp, to_free);
}
while (idp->id_free_cnt >= IDR_FREE_MAX) {
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
492,36 → 580,23
}
return;
}
EXPORT_SYMBOL(idr_remove);
 
 
/**
* idr_remove_all - remove all ids from the given idr tree
* @idp: idr handle
*
* idr_destroy() only frees up unused, cached idp_layers, but this
* function will remove all id mappings and leave all idp_layers
* unused.
*
* 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_remove_all() to remove all ids, and idr_destroy() to free
* up the cached idr_layers.
*/
void idr_remove_all(struct idr *idp)
void __idr_remove_all(struct idr *idp)
{
int n, id, max;
int bt_mask;
struct idr_layer *p;
struct idr_layer *pa[MAX_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;
533,7 → 608,7
/* Get the highest bit that the above add changed from 0->1. */
while (n < fls(id ^ bt_mask)) {
if (p)
free_layer(p);
free_layer(idp, p);
n += IDR_BITS;
p = *--paa;
}
540,46 → 615,54
}
idp->layers = 0;
}
EXPORT_SYMBOL(__idr_remove_all);
 
/**
* idr_destroy - release all cached layers within an idr tree
* @idp: idr handle
*
* Free all id mappings and all idp_layers. After this function, @idp is
* completely unused and can be freed / recycled. The caller is
* responsible for ensuring that no one else accesses @idp during or after
* 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
* free up the id mappings and cached idr_layers.
*/
void idr_destroy(struct idr *idp)
{
__idr_remove_all(idp);
 
while (idp->id_free_cnt) {
struct idr_layer *p = get_from_free_list(idp);
kfree(p);
}
}
EXPORT_SYMBOL(idr_destroy);
 
 
/**
* idr_find - return pointer for given id
* @idp: idr handle
* @id: lookup key
*
* Return the pointer given the id it has been registered with. A %NULL
* return indicates that @id is not valid or you passed %NULL in
* idr_get_new().
*
* This function can be called under rcu_read_lock(), given that the leaf
* pointers lifetimes are correctly managed.
*/
void *idr_find(struct idr *idp, int id)
void *idr_find_slowpath(struct idr *idp, int id)
{
int n;
struct idr_layer *p;
 
p = rcu_dereference(idp->top);
/*
* If @id is negative, idr_find() used to ignore the sign bit and
* performed lookup with the rest of bits, which is weird and can
* lead to very obscure bugs. We're now returning NULL for all
* negative IDs but just in case somebody was depending on the sign
* bit being ignored, let's trigger WARN_ON_ONCE() so that they can
* be detected and fixed. WARN_ON_ONCE() can later be removed.
*/
if (WARN_ON_ONCE(id < 0))
return NULL;
 
p = rcu_dereference_raw(idp->top);
if (!p)
return NULL;
n = (p->layer+1) * IDR_BITS;
 
/* Mask off upper bits we don't use for the search. */
id &= MAX_ID_MASK;
 
if (id >= (1 << n))
if (id > idr_max(p->layer + 1))
return NULL;
BUG_ON(n == 0);
 
586,10 → 669,11
while (n > 0 && p) {
n -= IDR_BITS;
BUG_ON(n != p->layer*IDR_BITS);
p = rcu_dereference(p->ary[(id >> n) & IDR_MASK]);
p = rcu_dereference_raw(p->ary[(id >> n) & IDR_MASK]);
}
return((void *)p);
}
EXPORT_SYMBOL(idr_find_slowpath);
 
#if 0
/**
615,19 → 699,19
{
int n, id, max, error = 0;
struct idr_layer *p;
struct idr_layer *pa[MAX_LEVEL];
struct idr_layer *pa[MAX_IDR_LEVEL + 1];
struct idr_layer **paa = &pa[0];
 
n = idp->layers * IDR_BITS;
p = rcu_dereference(idp->top);
max = 1 << n;
p = rcu_dereference_raw(idp->top);
max = idr_max(idp->layers);
 
id = 0;
while (id < max) {
while (id >= 0 && id <= max) {
while (n > 0 && p) {
n -= IDR_BITS;
*paa++ = p;
p = rcu_dereference(p->ary[(id >> n) & IDR_MASK]);
p = rcu_dereference_raw(p->ary[(id >> n) & IDR_MASK]);
}
 
if (p) {
655,27 → 739,29
* Returns pointer to registered object with id, which is next number to
* given id. After being looked up, *@nextidp will be updated for the next
* iteration.
*
* This function can be called under rcu_read_lock(), given that the leaf
* pointers lifetimes are correctly managed.
*/
 
void *idr_get_next(struct idr *idp, int *nextidp)
{
struct idr_layer *p, *pa[MAX_LEVEL];
struct idr_layer *p, *pa[MAX_IDR_LEVEL + 1];
struct idr_layer **paa = &pa[0];
int id = *nextidp;
int n, max;
 
/* find first ent */
n = idp->layers * IDR_BITS;
max = 1 << n;
p = rcu_dereference(idp->top);
p = rcu_dereference_raw(idp->top);
if (!p)
return NULL;
n = (p->layer + 1) * IDR_BITS;
max = idr_max(p->layer + 1);
 
while (id < max) {
while (id >= 0 && id <= max) {
while (n > 0 && p) {
n -= IDR_BITS;
*paa++ = p;
p = rcu_dereference(p->ary[(id >> n) & IDR_MASK]);
p = rcu_dereference_raw(p->ary[(id >> n) & IDR_MASK]);
}
 
if (p) {
683,7 → 769,14
return p;
}
 
id += 1 << n;
/*
* Proceed to the next layer at the current level. Unlike
* idr_for_each(), @id isn't guaranteed to be aligned to
* layer boundary at this point and adding 1 << n may
* incorrectly skip IDs. Make sure we jump to the
* beginning of the next layer using round_up().
*/
id = round_up(id + 1, 1 << n);
while (n < fls(id)) {
n += IDR_BITS;
p = *--paa;
691,9 → 784,9
}
return NULL;
}
EXPORT_SYMBOL(idr_get_next);
 
 
 
/**
* idr_replace - replace pointer for given id
* @idp: idr handle
711,6 → 804,10
int n;
struct idr_layer *p, *old_p;
 
/* see comment in idr_find_slowpath() */
if (WARN_ON_ONCE(id < 0))
return ERR_PTR(-EINVAL);
 
p = idp->top;
if (!p)
return ERR_PTR(-EINVAL);
717,8 → 814,6
 
n = (p->layer+1) * IDR_BITS;
 
id &= MAX_ID_MASK;
 
if (id >= (1 << n))
return ERR_PTR(-EINVAL);
 
729,7 → 824,7
}
 
n = id & IDR_MASK;
if (unlikely(p == NULL || !test_bit(n, &p->bitmap)))
if (unlikely(p == NULL || !test_bit(n, p->bitmap)))
return ERR_PTR(-ENOENT);
 
old_p = p->ary[n];
759,12 → 854,14
void idr_init(struct idr *idp)
{
memset(idp, 0, sizeof(struct idr));
// spin_lock_init(&idp->lock);
spin_lock_init(&idp->lock);
}
EXPORT_SYMBOL(idr_init);
 
#if 0
 
/*
/**
* DOC: IDA description
* IDA - IDR based ID allocator
*
* This is id allocator without id -> pointer translation. Memory
813,7 → 910,7
if (!ida->free_bitmap) {
struct ida_bitmap *bitmap;
 
bitmap = kzalloc(sizeof(struct ida_bitmap), gfp_mask);
bitmap = kmalloc(sizeof(struct ida_bitmap), gfp_mask);
if (!bitmap)
return 0;
 
841,7 → 938,7
*/
int ida_get_new_above(struct ida *ida, int starting_id, int *p_id)
{
struct idr_layer *pa[MAX_LEVEL];
struct idr_layer *pa[MAX_IDR_LEVEL + 1];
struct ida_bitmap *bitmap;
unsigned long flags;
int idr_id = starting_id / IDA_BITMAP_BITS;
850,11 → 947,11
 
restart:
/* get vacant slot */
t = idr_get_empty_slot(&ida->idr, idr_id, pa);
t = idr_get_empty_slot(&ida->idr, idr_id, pa, 0, &ida->idr);
if (t < 0)
return _idr_rc_to_errno(t);
return t == -ENOMEM ? -EAGAIN : t;
 
if (t * IDA_BITMAP_BITS >= MAX_ID_BIT)
if (t * IDA_BITMAP_BITS >= MAX_IDR_BIT)
return -ENOSPC;
 
if (t != idr_id)
888,7 → 985,7
}
 
id = idr_id * IDA_BITMAP_BITS + t;
if (id >= MAX_ID_BIT)
if (id >= MAX_IDR_BIT)
return -ENOSPC;
 
__set_bit(t, bitmap->bitmap);
913,25 → 1010,6
EXPORT_SYMBOL(ida_get_new_above);
 
/**
* ida_get_new - allocate new ID
* @ida: idr handle
* @p_id: pointer to the allocated handle
*
* Allocate new ID. It should be called with any required locks.
*
* If memory is required, it will return %-EAGAIN, you should unlock
* and go back to the idr_pre_get() call. If the idr is full, it will
* return %-ENOSPC.
*
* @p_id returns a value in the range %0 ... %0x7fffffff.
*/
int ida_get_new(struct ida *ida, int *p_id)
{
return ida_get_new_above(ida, 0, p_id);
}
EXPORT_SYMBOL(ida_get_new);
 
/**
* ida_remove - remove the given ID
* @ida: ida handle
* @id: ID to free
948,7 → 1026,7
/* clear full bits while looking up the leaf idr_layer */
while ((shift > 0) && p) {
n = (idr_id >> shift) & IDR_MASK;
__clear_bit(n, &p->bitmap);
__clear_bit(n, p->bitmap);
p = p->ary[n];
shift -= IDR_BITS;
}
957,7 → 1035,7
goto err;
 
n = idr_id & IDR_MASK;
__clear_bit(n, &p->bitmap);
__clear_bit(n, p->bitmap);
 
bitmap = (void *)p->ary[n];
if (!test_bit(offset, bitmap->bitmap))
966,7 → 1044,7
/* update bitmap and remove it if empty */
__clear_bit(offset, bitmap->bitmap);
if (--bitmap->nr_busy == 0) {
__set_bit(n, &p->bitmap); /* to please idr_remove() */
__set_bit(n, p->bitmap); /* to please idr_remove() */
idr_remove(&ida->idr, idr_id);
free_bitmap(ida, bitmap);
}
1007,3 → 1085,114
 
 
#endif
 
 
unsigned long find_first_bit(const unsigned long *addr, unsigned long size)
{
const unsigned long *p = addr;
unsigned long result = 0;
unsigned long tmp;
 
while (size & ~(BITS_PER_LONG-1)) {
if ((tmp = *(p++)))
goto found;
result += BITS_PER_LONG;
size -= BITS_PER_LONG;
}
if (!size)
return result;
 
tmp = (*p) & (~0UL >> (BITS_PER_LONG - size));
if (tmp == 0UL) /* Are any bits set? */
return result + size; /* Nope. */
found:
return result + __ffs(tmp);
}
 
unsigned long find_next_bit(const unsigned long *addr, unsigned long size,
unsigned long offset)
{
const unsigned long *p = addr + BITOP_WORD(offset);
unsigned long result = offset & ~(BITS_PER_LONG-1);
unsigned long tmp;
 
if (offset >= size)
return size;
size -= result;
offset %= BITS_PER_LONG;
if (offset) {
tmp = *(p++);
tmp &= (~0UL << offset);
if (size < BITS_PER_LONG)
goto found_first;
if (tmp)
goto found_middle;
size -= BITS_PER_LONG;
result += BITS_PER_LONG;
}
while (size & ~(BITS_PER_LONG-1)) {
if ((tmp = *(p++)))
goto found_middle;
result += BITS_PER_LONG;
size -= BITS_PER_LONG;
}
if (!size)
return result;
tmp = *p;
 
found_first:
tmp &= (~0UL >> (BITS_PER_LONG - size));
if (tmp == 0UL) /* Are any bits set? */
return result + size; /* Nope. */
found_middle:
return result + __ffs(tmp);
}
 
unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size,
unsigned long offset)
{
const unsigned long *p = addr + BITOP_WORD(offset);
unsigned long result = offset & ~(BITS_PER_LONG-1);
unsigned long tmp;
 
if (offset >= size)
return size;
size -= result;
offset %= BITS_PER_LONG;
if (offset) {
tmp = *(p++);
tmp |= ~0UL >> (BITS_PER_LONG - offset);
if (size < BITS_PER_LONG)
goto found_first;
if (~tmp)
goto found_middle;
size -= BITS_PER_LONG;
result += BITS_PER_LONG;
}
while (size & ~(BITS_PER_LONG-1)) {
if (~(tmp = *(p++)))
goto found_middle;
result += BITS_PER_LONG;
size -= BITS_PER_LONG;
}
if (!size)
return result;
tmp = *p;
 
found_first:
tmp |= ~0UL << size;
if (tmp == ~0UL) /* Are any bits zero? */
return result + size; /* Nope. */
found_middle:
return result + ffz(tmp);
}
 
unsigned int hweight32(unsigned int w)
{
unsigned int res = w - ((w >> 1) & 0x55555555);
res = (res & 0x33333333) + ((res >> 2) & 0x33333333);
res = (res + (res >> 4)) & 0x0F0F0F0F;
res = res + (res >> 8);
return (res + (res >> 16)) & 0x000000FF;
}