mirror of
https://github.com/hermitcore/libhermit.git
synced 2025-03-09 00:00:03 +01:00
268 lines
6.9 KiB
C
268 lines
6.9 KiB
C
/*
|
|
* Copyright (c) 2014, Steffen Vogel, RWTH Aachen University
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions are met:
|
|
* * Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* * Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* * Neither the name of the University nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this
|
|
* software without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
|
|
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
|
* DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
|
|
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
|
|
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
|
|
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
|
|
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
|
|
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
/**
|
|
* @author Steffen Vogel <steffen.vogel@rwth-aachen.de>
|
|
*/
|
|
|
|
#include <hermit/stdio.h>
|
|
#include <hermit/malloc.h>
|
|
#include <hermit/spinlock.h>
|
|
#include <hermit/memory.h>
|
|
#include <hermit/logging.h>
|
|
#include <asm/page.h>
|
|
|
|
/// A linked list for each binary size exponent
|
|
static buddy_t* buddy_lists[BUDDY_LISTS] = { [0 ... BUDDY_LISTS-1] = NULL };
|
|
|
|
extern spinlock_irqsave_t hermit_mm_lock;
|
|
|
|
/** @brief Check if larger free buddies are available */
|
|
static inline int buddy_large_avail(uint8_t exp)
|
|
{
|
|
while ((exp<BUDDY_MAX) && !buddy_lists[exp-BUDDY_MIN])
|
|
exp++;
|
|
|
|
return exp != BUDDY_MAX;
|
|
}
|
|
|
|
/** @brief Calculate the required buddy size */
|
|
static inline int buddy_exp(size_t sz)
|
|
{
|
|
int exp;
|
|
for (exp=0; sz>(1<<exp); exp++);
|
|
|
|
if (exp > BUDDY_MAX)
|
|
exp = 0;
|
|
if (exp < BUDDY_MIN)
|
|
exp = BUDDY_MIN;
|
|
|
|
return exp;
|
|
}
|
|
|
|
/** @brief Get a free buddy by potentially splitting a larger one */
|
|
static buddy_t* buddy_get(int exp)
|
|
{
|
|
spinlock_irqsave_lock(&hermit_mm_lock);
|
|
buddy_t** list = &buddy_lists[exp-BUDDY_MIN];
|
|
buddy_t* buddy = *list;
|
|
buddy_t* split;
|
|
|
|
if (buddy)
|
|
// there is already a free buddy =>
|
|
// we remove it from the list
|
|
*list = buddy->next;
|
|
else if ((exp >= BUDDY_ALLOC) && !buddy_large_avail(exp))
|
|
// theres no free buddy larger than exp =>
|
|
// we can allocate new memory
|
|
buddy = (buddy_t*) palloc(1<<exp, VMA_HEAP|VMA_CACHEABLE);
|
|
else {
|
|
// we recursivly request a larger buddy...
|
|
buddy = buddy_get(exp+1);
|
|
if (BUILTIN_EXPECT(!buddy, 0))
|
|
goto out;
|
|
|
|
// ... and split it, by putting the second half back to the list
|
|
split = (buddy_t*) ((size_t) buddy + (1<<exp));
|
|
split->next = *list;
|
|
*list = split;
|
|
}
|
|
|
|
out:
|
|
spinlock_irqsave_unlock(&hermit_mm_lock);
|
|
|
|
return buddy;
|
|
}
|
|
|
|
/** @brief Put a buddy back to its free list
|
|
*
|
|
* TODO: merge adjacent buddies (memory compaction)
|
|
*/
|
|
static void buddy_put(buddy_t* buddy)
|
|
{
|
|
spinlock_irqsave_lock(&hermit_mm_lock);
|
|
buddy_t** list = &buddy_lists[buddy->prefix.exponent-BUDDY_MIN];
|
|
buddy->next = *list;
|
|
*list = buddy;
|
|
spinlock_irqsave_unlock(&hermit_mm_lock);
|
|
}
|
|
|
|
void buddy_dump(void)
|
|
{
|
|
size_t free = 0;
|
|
int i;
|
|
|
|
for (i=0; i<BUDDY_LISTS; i++) {
|
|
buddy_t* buddy;
|
|
int exp = i+BUDDY_MIN;
|
|
|
|
if (buddy_lists[i])
|
|
LOG_INFO("buddy_list[%u] (exp=%u, size=%lu bytes):\n", i, exp, 1<<exp);
|
|
|
|
for (buddy=buddy_lists[i]; buddy; buddy=buddy->next) {
|
|
LOG_INFO(" %p -> %p \n", buddy, buddy->next);
|
|
free += 1<<exp;
|
|
}
|
|
}
|
|
LOG_INFO("free buddies: %lu bytes\n", free);
|
|
}
|
|
|
|
void* palloc(size_t sz, uint32_t flags)
|
|
{
|
|
size_t phyaddr, viraddr, bits;
|
|
uint32_t npages = PAGE_CEIL(sz) >> PAGE_BITS;
|
|
int err;
|
|
|
|
LOG_DEBUG("palloc(%zd) (%u pages)\n", sz, npages);
|
|
|
|
// get free virtual address space
|
|
viraddr = vma_alloc(PAGE_CEIL(sz), flags);
|
|
if (BUILTIN_EXPECT(!viraddr, 0))
|
|
return NULL;
|
|
|
|
// get continous physical pages
|
|
phyaddr = get_pages(npages);
|
|
if (BUILTIN_EXPECT(!phyaddr, 0)) {
|
|
vma_free(viraddr, viraddr+npages*PAGE_SIZE);
|
|
return NULL;
|
|
}
|
|
|
|
//TODO: interpretation of from (vma) flags is missing
|
|
bits = PG_RW|PG_GLOBAL|PG_NX;
|
|
|
|
// map physical pages to VMA
|
|
err = page_map(viraddr, phyaddr, npages, bits);
|
|
if (BUILTIN_EXPECT(err, 0)) {
|
|
vma_free(viraddr, viraddr+npages*PAGE_SIZE);
|
|
put_pages(phyaddr, npages);
|
|
return NULL;
|
|
}
|
|
|
|
return (void*) viraddr;
|
|
}
|
|
|
|
void* create_stack(size_t sz)
|
|
{
|
|
size_t phyaddr, viraddr, bits;
|
|
uint32_t npages = PAGE_CEIL(sz) >> PAGE_BITS;
|
|
int err;
|
|
|
|
LOG_DEBUG("create_stack(0x%zx) (%u pages)\n", DEFAULT_STACK_SIZE, npages);
|
|
|
|
if (BUILTIN_EXPECT(!sz, 0))
|
|
return NULL;
|
|
|
|
// get free virtual address space
|
|
viraddr = vma_alloc((npages+2)*PAGE_SIZE, VMA_READ|VMA_WRITE|VMA_CACHEABLE);
|
|
if (BUILTIN_EXPECT(!viraddr, 0))
|
|
return NULL;
|
|
|
|
// get continous physical pages
|
|
phyaddr = get_pages(npages);
|
|
if (BUILTIN_EXPECT(!phyaddr, 0)) {
|
|
vma_free(viraddr, viraddr+(npages+2)*PAGE_SIZE);
|
|
return NULL;
|
|
}
|
|
|
|
bits = PG_RW|PG_GLOBAL|PG_NX;
|
|
|
|
// map physical pages to VMA
|
|
err = page_map(viraddr+PAGE_SIZE, phyaddr, npages, bits);
|
|
if (BUILTIN_EXPECT(err, 0)) {
|
|
vma_free(viraddr, viraddr+(npages+2)*PAGE_SIZE);
|
|
put_pages(phyaddr, npages);
|
|
return NULL;
|
|
}
|
|
|
|
return (void*) (viraddr+PAGE_SIZE);
|
|
}
|
|
|
|
int destroy_stack(void* viraddr, size_t sz)
|
|
{
|
|
size_t phyaddr;
|
|
uint32_t npages = PAGE_CEIL(sz) >> PAGE_BITS;
|
|
|
|
LOG_DEBUG("destroy_stack(0x%zx) (size 0x%zx)\n", viraddr, DEFAULT_STACK_SIZE);
|
|
|
|
if (BUILTIN_EXPECT(!viraddr, 0))
|
|
return -EINVAL;
|
|
if (BUILTIN_EXPECT(!sz, 0))
|
|
return -EINVAL;
|
|
|
|
phyaddr = virt_to_phys((size_t)viraddr);
|
|
if (BUILTIN_EXPECT(!phyaddr, 0))
|
|
return -ENOMEM;
|
|
|
|
// unmap and destroy stack
|
|
vma_free((size_t)viraddr-PAGE_SIZE, (size_t)viraddr+(npages+1)*PAGE_SIZE);
|
|
page_unmap((size_t)viraddr, npages);
|
|
put_pages(phyaddr, npages);
|
|
|
|
return 0;
|
|
}
|
|
|
|
void* kmalloc(size_t sz)
|
|
{
|
|
if (BUILTIN_EXPECT(!sz, 0))
|
|
return NULL;
|
|
|
|
// add space for the prefix
|
|
sz += sizeof(buddy_t);
|
|
|
|
int exp = buddy_exp(sz);
|
|
if (BUILTIN_EXPECT(!exp, 0))
|
|
return NULL;
|
|
|
|
buddy_t* buddy = buddy_get(exp);
|
|
if (BUILTIN_EXPECT(!buddy, 0))
|
|
return NULL;
|
|
|
|
// setup buddy prefix
|
|
buddy->prefix.magic = BUDDY_MAGIC;
|
|
buddy->prefix.exponent = exp;
|
|
|
|
LOG_DEBUG("kmalloc(%zd) = %p\n", sz, buddy+1);
|
|
|
|
// pointer arithmetic: we hide the prefix
|
|
return buddy+1;
|
|
}
|
|
|
|
void kfree(void *addr)
|
|
{
|
|
if (BUILTIN_EXPECT(!addr, 0))
|
|
return;
|
|
|
|
LOG_DEBUG("kfree(%p)\n", addr);
|
|
|
|
buddy_t* buddy = (buddy_t*) addr - 1; // get prefix
|
|
|
|
// check magic
|
|
if (BUILTIN_EXPECT(buddy->prefix.magic != BUDDY_MAGIC, 0))
|
|
return;
|
|
|
|
buddy_put(buddy);
|
|
}
|