diff options
Diffstat (limited to 'arch/sandbox/cpu')
-rw-r--r-- | arch/sandbox/cpu/os.c | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/arch/sandbox/cpu/os.c b/arch/sandbox/cpu/os.c index 3d8af0a..d23aad3 100644 --- a/arch/sandbox/cpu/os.c +++ b/arch/sandbox/cpu/os.c @@ -267,11 +267,18 @@ void os_tty_raw(int fd, bool allow_sigs) signal(SIGINT, os_sigint_handler); } +/* + * Provide our own malloc so we don't use space in the sandbox ram_buf for + * allocations that are internal to sandbox, or need to be done before U-Boot's + * malloc() is ready. + */ void *os_malloc(size_t length) { int page_size = getpagesize(); struct os_mem_hdr *hdr; + if (!length) + return NULL; /* * Use an address that is hopefully available to us so that pointers * to this memory are fairly obvious. If we end up with a different @@ -298,6 +305,47 @@ void os_free(void *ptr) } } +/* These macros are from kernel.h but not accessible in this file */ +#define ALIGN(x, a) __ALIGN_MASK((x), (typeof(x))(a) - 1) +#define __ALIGN_MASK(x, mask) (((x) + (mask)) & ~(mask)) + +/* + * Provide our own malloc so we don't use space in the sandbox ram_buf for + * allocations that are internal to sandbox, or need to be done before U-Boot's + * malloc() is ready. + */ +void *os_realloc(void *ptr, size_t length) +{ + int page_size = getpagesize(); + struct os_mem_hdr *hdr; + void *new_ptr; + + /* Reallocating a NULL pointer is just an alloc */ + if (!ptr) + return os_malloc(length); + + /* Changing a length to 0 is just a free */ + if (length) { + os_free(ptr); + return NULL; + } + + /* + * If the new size is the same number of pages as the old, nothing to + * do. There isn't much point in shrinking things + */ + hdr = ptr - page_size; + if (ALIGN(length, page_size) <= ALIGN(hdr->length, page_size)) + return ptr; + + /* We have to grow it, so allocate something new */ + new_ptr = os_malloc(length); + memcpy(new_ptr, ptr, hdr->length); + os_free(ptr); + + return new_ptr; +} + void os_usleep(unsigned long usec) { usleep(usec); |