File: [Development] / linux-2.6-xfs-all / lib / genalloc.c (download)
Revision 1.6, Wed Sep 12 17:09:56 2007 UTC (10 years, 1 month ago) by tes.longdrop.melbourne.sgi.com
Branch: MAIN
CVS Tags: HEAD Changes since 1.5: +1 -2
lines
Update 2.6.x-xfs to 2.6.23-rc4.
Also update fs/xfs with external mainline changes.
There were 12 such missing commits that I detected:
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commit ad690ef9e690f6c31f7d310b09ef1314bcec9033
Author: Al Viro <viro@ftp.linux.org.uk>
xfs ioctl __user annotations
commit 20c2df83d25c6a95affe6157a4c9cac4cf5ffaac
Author: Paul Mundt <lethal@linux-sh.org>
mm: Remove slab destructors from kmem_cache_create().
commit d0217ac04ca6591841e5665f518e38064f4e65bd
Author: Nick Piggin <npiggin@suse.de>
mm: fault feedback #1
commit 54cb8821de07f2ffcd28c380ce9b93d5784b40d7
Author: Nick Piggin <npiggin@suse.de>
mm: merge populate and nopage into fault (fixes nonlinear)
commit d00806b183152af6d24f46f0c33f14162ca1262a
Author: Nick Piggin <npiggin@suse.de>
mm: fix fault vs invalidate race for linear mappings
commit a569425512253992cc64ebf8b6d00a62f986db3e
Author: Christoph Hellwig <hch@infradead.org>
knfsd: exportfs: add exportfs.h header
commit 831441862956fffa17b9801db37e6ea1650b0f69
Author: Rafael J. Wysocki <rjw@sisk.pl>
Freezer: make kernel threads nonfreezable by default
commit 8e1f936b73150f5095448a0fee6d4f30a1f9001d
Author: Rusty Russell <rusty@rustcorp.com.au>
mm: clean up and kernelify shrinker registration
commit 5ffc4ef45b3b0a57872f631b4e4ceb8ace0d7496
Author: Jens Axboe <jens.axboe@oracle.com>
sendfile: remove .sendfile from filesystems that use generic_file_sendfile()
commit 8bb7844286fb8c9fce6f65d8288aeb09d03a5e0d
Author: Rafael J. Wysocki <rjw@sisk.pl>
Add suspend-related notifications for CPU hotplug
commit 59c51591a0ac7568824f541f57de967e88adaa07
Author: Michael Opdenacker <michael@free-electrons.com>
Fix occurrences of "the the "
commit 0ceb331433e8aad9c5f441a965d7c681f8b9046f
Author: Dmitriy Monakhov <dmonakhov@openvz.org>
mm: move common segment checks to separate helper function
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Merge of 2.6.x-xfs-melb:linux:29656b by kenmcd.
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/*
* Basic general purpose allocator for managing special purpose memory
* not managed by the regular kmalloc/kfree interface.
* Uses for this includes on-device special memory, uncached memory
* etc.
*
* Copyright 2005 (C) Jes Sorensen <jes@trained-monkey.org>
*
* This source code is licensed under the GNU General Public License,
* Version 2. See the file COPYING for more details.
*/
#include <linux/module.h>
#include <linux/genalloc.h>
/**
* gen_pool_create - create a new special memory pool
* @min_alloc_order: log base 2 of number of bytes each bitmap bit represents
* @nid: node id of the node the pool structure should be allocated on, or -1
*
* Create a new special memory pool that can be used to manage special purpose
* memory not managed by the regular kmalloc/kfree interface.
*/
struct gen_pool *gen_pool_create(int min_alloc_order, int nid)
{
struct gen_pool *pool;
pool = kmalloc_node(sizeof(struct gen_pool), GFP_KERNEL, nid);
if (pool != NULL) {
rwlock_init(&pool->lock);
INIT_LIST_HEAD(&pool->chunks);
pool->min_alloc_order = min_alloc_order;
}
return pool;
}
EXPORT_SYMBOL(gen_pool_create);
/**
* gen_pool_add - add a new chunk of special memory to the pool
* @pool: pool to add new memory chunk to
* @addr: starting address of memory chunk to add to pool
* @size: size in bytes of the memory chunk to add to pool
* @nid: node id of the node the chunk structure and bitmap should be
* allocated on, or -1
*
* Add a new chunk of special memory to the specified pool.
*/
int gen_pool_add(struct gen_pool *pool, unsigned long addr, size_t size,
int nid)
{
struct gen_pool_chunk *chunk;
int nbits = size >> pool->min_alloc_order;
int nbytes = sizeof(struct gen_pool_chunk) +
(nbits + BITS_PER_BYTE - 1) / BITS_PER_BYTE;
chunk = kmalloc_node(nbytes, GFP_KERNEL | __GFP_ZERO, nid);
if (unlikely(chunk == NULL))
return -1;
spin_lock_init(&chunk->lock);
chunk->start_addr = addr;
chunk->end_addr = addr + size;
write_lock(&pool->lock);
list_add(&chunk->next_chunk, &pool->chunks);
write_unlock(&pool->lock);
return 0;
}
EXPORT_SYMBOL(gen_pool_add);
/**
* gen_pool_destroy - destroy a special memory pool
* @pool: pool to destroy
*
* Destroy the specified special memory pool. Verifies that there are no
* outstanding allocations.
*/
void gen_pool_destroy(struct gen_pool *pool)
{
struct list_head *_chunk, *_next_chunk;
struct gen_pool_chunk *chunk;
int order = pool->min_alloc_order;
int bit, end_bit;
write_lock(&pool->lock);
list_for_each_safe(_chunk, _next_chunk, &pool->chunks) {
chunk = list_entry(_chunk, struct gen_pool_chunk, next_chunk);
list_del(&chunk->next_chunk);
end_bit = (chunk->end_addr - chunk->start_addr) >> order;
bit = find_next_bit(chunk->bits, end_bit, 0);
BUG_ON(bit < end_bit);
kfree(chunk);
}
kfree(pool);
return;
}
EXPORT_SYMBOL(gen_pool_destroy);
/**
* gen_pool_alloc - allocate special memory from the pool
* @pool: pool to allocate from
* @size: number of bytes to allocate from the pool
*
* Allocate the requested number of bytes from the specified pool.
* Uses a first-fit algorithm.
*/
unsigned long gen_pool_alloc(struct gen_pool *pool, size_t size)
{
struct list_head *_chunk;
struct gen_pool_chunk *chunk;
unsigned long addr, flags;
int order = pool->min_alloc_order;
int nbits, bit, start_bit, end_bit;
if (size == 0)
return 0;
nbits = (size + (1UL << order) - 1) >> order;
read_lock(&pool->lock);
list_for_each(_chunk, &pool->chunks) {
chunk = list_entry(_chunk, struct gen_pool_chunk, next_chunk);
end_bit = (chunk->end_addr - chunk->start_addr) >> order;
end_bit -= nbits + 1;
spin_lock_irqsave(&chunk->lock, flags);
bit = -1;
while (bit + 1 < end_bit) {
bit = find_next_zero_bit(chunk->bits, end_bit, bit + 1);
if (bit >= end_bit)
break;
start_bit = bit;
if (nbits > 1) {
bit = find_next_bit(chunk->bits, bit + nbits,
bit + 1);
if (bit - start_bit < nbits)
continue;
}
addr = chunk->start_addr +
((unsigned long)start_bit << order);
while (nbits--)
__set_bit(start_bit++, chunk->bits);
spin_unlock_irqrestore(&chunk->lock, flags);
read_unlock(&pool->lock);
return addr;
}
spin_unlock_irqrestore(&chunk->lock, flags);
}
read_unlock(&pool->lock);
return 0;
}
EXPORT_SYMBOL(gen_pool_alloc);
/**
* gen_pool_free - free allocated special memory back to the pool
* @pool: pool to free to
* @addr: starting address of memory to free back to pool
* @size: size in bytes of memory to free
*
* Free previously allocated special memory back to the specified pool.
*/
void gen_pool_free(struct gen_pool *pool, unsigned long addr, size_t size)
{
struct list_head *_chunk;
struct gen_pool_chunk *chunk;
unsigned long flags;
int order = pool->min_alloc_order;
int bit, nbits;
nbits = (size + (1UL << order) - 1) >> order;
read_lock(&pool->lock);
list_for_each(_chunk, &pool->chunks) {
chunk = list_entry(_chunk, struct gen_pool_chunk, next_chunk);
if (addr >= chunk->start_addr && addr < chunk->end_addr) {
BUG_ON(addr + size > chunk->end_addr);
spin_lock_irqsave(&chunk->lock, flags);
bit = (addr - chunk->start_addr) >> order;
while (nbits--)
__clear_bit(bit++, chunk->bits);
spin_unlock_irqrestore(&chunk->lock, flags);
break;
}
}
BUG_ON(nbits > 0);
read_unlock(&pool->lock);
}
EXPORT_SYMBOL(gen_pool_free);