diff options
Diffstat (limited to 'frontend/linux/plat_mmap.c')
| -rw-r--r-- | frontend/linux/plat_mmap.c | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/frontend/linux/plat_mmap.c b/frontend/linux/plat_mmap.c new file mode 100644 index 0000000..db661b6 --- /dev/null +++ b/frontend/linux/plat_mmap.c @@ -0,0 +1,91 @@ +/* + * (C) GraÅžvydas "notaz" Ignotas, 2008-2010 + * + * This work is licensed under the terms of any of these licenses + * (at your option): + * - GNU GPL, version 2 or later. + * - GNU LGPL, version 2.1 or later. + * See the COPYING file in the top-level directory. + */ + +#define _GNU_SOURCE 1 +#include <stdio.h> +#include <string.h> +#include <stdarg.h> +#include <unistd.h> +#include <sys/mman.h> +#include <errno.h> + +// this is some dupe code to avoid libpicofe dep + +//#include "../libpicofe/plat.h" + +/* XXX: maybe unhardcode pagesize? */ +#define HUGETLB_PAGESIZE (2 * 1024 * 1024) +#define HUGETLB_THRESHOLD (HUGETLB_PAGESIZE / 2) +#ifndef MAP_HUGETLB +#define MAP_HUGETLB 0x40000 /* arch specific */ +#endif + +void *plat_mmap(unsigned long addr, size_t size, int need_exec, int is_fixed) +{ + static int hugetlb_disabled; + int prot = PROT_READ | PROT_WRITE; + int flags = MAP_PRIVATE | MAP_ANONYMOUS; + void *req, *ret; + + req = (void *)addr; + if (need_exec) + prot |= PROT_EXEC; + if (is_fixed) + flags |= MAP_FIXED; + if (size >= HUGETLB_THRESHOLD && !hugetlb_disabled) + flags |= MAP_HUGETLB; + + ret = mmap(req, size, prot, flags, -1, 0); + if (ret == MAP_FAILED && (flags & MAP_HUGETLB)) { + fprintf(stderr, + "warning: failed to do hugetlb mmap (%p, %zu): %d\n", + req, size, errno); + hugetlb_disabled = 1; + flags &= ~MAP_HUGETLB; + ret = mmap(req, size, prot, flags, -1, 0); + } + if (ret == MAP_FAILED) + return NULL; + + if (req != NULL && ret != req) + fprintf(stderr, + "warning: mmaped to %p, requested %p\n", ret, req); + + return ret; +} + +void *plat_mremap(void *ptr, size_t oldsize, size_t newsize) +{ + void *ret; + + ret = mremap(ptr, oldsize, newsize, MREMAP_MAYMOVE); + if (ret == MAP_FAILED) + return NULL; + if (ret != ptr) + printf("warning: mremap moved: %p -> %p\n", ptr, ret); + + return ret; +} + +void plat_munmap(void *ptr, size_t size) +{ + int ret; + + ret = munmap(ptr, size); + if (ret != 0 && (size & (HUGETLB_PAGESIZE - 1))) { + // prehaps an autorounded hugetlb mapping? + size = (size + HUGETLB_PAGESIZE - 1) & ~(HUGETLB_PAGESIZE - 1); + ret = munmap(ptr, size); + } + if (ret != 0) { + fprintf(stderr, + "munmap(%p, %zu) failed: %d\n", ptr, size, errno); + } +} |