On 02/11/2016 21:52, Andrew Jones wrote:
> Ensure we're page aligned, add locking, just return if NULL is
> passed to vfree().
>
> Signed-off-by: Andrew Jones <drjones@xxxxxxxxxx>
> ---
> lib/x86/asm/page.h | 2 ++
> lib/x86/vm.c | 44 +++++++++++++++++++++++++++++++++++++-------
> 2 files changed, 39 insertions(+), 7 deletions(-)
>
> diff --git a/lib/x86/asm/page.h b/lib/x86/asm/page.h
> index 5044a49ab0cc..dd999304f1f0 100644
> --- a/lib/x86/asm/page.h
> +++ b/lib/x86/asm/page.h
> @@ -16,6 +16,8 @@
>
> #ifndef __ASSEMBLY__
>
> +#define PAGE_ALIGN(addr) ALIGN(addr, PAGE_SIZE)
> +
> #ifdef __x86_64__
> #define LARGE_PAGE_SIZE (512 * PAGE_SIZE)
> #else
> diff --git a/lib/x86/vm.c b/lib/x86/vm.c
> index f7e778b3779c..baea17e7f475 100644
> --- a/lib/x86/vm.c
> +++ b/lib/x86/vm.c
> @@ -1,37 +1,54 @@
> #include "fwcfg.h"
> #include "vm.h"
> #include "libcflat.h"
> +#include "asm/spinlock.h"
>
> +static struct spinlock heap_lock;
> +static struct spinlock vm_lock;
> static void *free = 0;
> static void *vfree_top = 0;
>
> static void free_memory(void *mem, unsigned long size)
> {
> + assert(!((unsigned long)mem & ~PAGE_MASK));
> +
> + spin_lock(&heap_lock);
> +
> + free = NULL;
> +
> while (size >= PAGE_SIZE) {
> *(void **)mem = free;
> free = mem;
> mem += PAGE_SIZE;
> size -= PAGE_SIZE;
> }
> +
> + spin_unlock(&heap_lock);
> }
>
> void *alloc_page()
> {
> void *p;
>
> + spin_lock(&heap_lock);
> +
> if (!free)
> - return 0;
> + return NULL;
You must unlock heap_lock before return
Laurent
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