* UCW Library -- Allocation of Large Aligned Buffers
*
* (c) 2006 Martin Mares <mj@ucw.cz>
+ * (c) 2007 Pavel Charvat <char@ucw.cz>
*
* This software may be freely distributed and used according to the terms
* of the GNU Lesser General Public License.
#include "lib/lib.h"
#include <sys/mman.h>
+#include <string.h>
+
+void *
+page_alloc(unsigned int len)
+{
+ ASSERT(!(len & (CPU_PAGE_SIZE-1)));
+ byte *p = mmap(NULL, len, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
+ if (p == (byte*) MAP_FAILED)
+ die("Cannot mmap %d bytes of memory: %m", len);
+ return p;
+}
+
+void
+page_free(void *start, unsigned int len)
+{
+ ASSERT(!(len & (CPU_PAGE_SIZE-1)));
+ ASSERT(!((uintptr_t) start & (CPU_PAGE_SIZE-1)));
+ munmap(start, len);
+}
+
+void *
+page_realloc(void *start, unsigned int old_len, unsigned int new_len)
+{
+ void *p = page_alloc(new_len);
+ memcpy(p, start, MIN(old_len, new_len));
+ page_free(start, old_len);
+ return p;
+}
static unsigned int
big_round(unsigned int len)
#ifdef CONFIG_DEBUG
len += 2*CPU_PAGE_SIZE;
#endif
- byte *p = mmap(NULL, len, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
- if (p == (byte*) MAP_FAILED)
- die("Cannot mmap %d bytes of memory: %m", len);
+ byte *p = page_alloc(len);
#ifdef CONFIG_DEBUG
mprotect(p, CPU_PAGE_SIZE, PROT_NONE);
mprotect(p+len-CPU_PAGE_SIZE, CPU_PAGE_SIZE, PROT_NONE);
big_free(void *start, unsigned int len)
{
byte *p = start;
- ASSERT(!((addr_int_t) p & (CPU_PAGE_SIZE-1)));
len = big_round(len);
#ifdef CONFIG_DEBUG
p -= CPU_PAGE_SIZE;
len += 2*CPU_PAGE_SIZE;
#endif
- munmap(p, len);
+ page_free(p, len);
}
#ifdef TEST