On 02/11/2016 21:52, Andrew Jones wrote:
> This will allow other arches to use {alloc,free}_page.
Let's make a new file lib/pagealloc.c. This could potentially grow to
something like a buddy allocator.
Paolo
> Signed-off-by: Andrew Jones <drjones@xxxxxxxxxx>
> ---
> lib/alloc.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
> lib/alloc.h | 10 ++++++++++
> lib/x86/vm.c | 48 ++----------------------------------------------
> x86/Makefile.common | 1 +
> 4 files changed, 62 insertions(+), 46 deletions(-)
>
> diff --git a/lib/alloc.c b/lib/alloc.c
> index 1d990a803825..ce1198e2977f 100644
> --- a/lib/alloc.c
> +++ b/lib/alloc.c
> @@ -5,6 +5,7 @@
> */
> #include "alloc.h"
> #include "asm/spinlock.h"
> +#include "asm/page.h"
> #include "asm/io.h"
>
> #define MIN(a, b) ((a) < (b) ? (a) : (b))
> @@ -150,6 +151,54 @@ phys_addr_t phys_zalloc(phys_addr_t size)
> return phys_zalloc_aligned(size, phys_alloc_align_min);
> }
>
> +static struct spinlock heap_lock;
> +static void *heap_free_head;
> +
> +void heap_init(void *start, size_t size)
> +{
> + void *p = start;
> +
> + assert(!((unsigned long)start & ~PAGE_MASK));
> +
> + spin_lock(&heap_lock);
> +
> + heap_free_head = NULL;
> +
> + while (size >= PAGE_SIZE) {
> + *(void **)p = heap_free_head;
> + heap_free_head = p;
> + p += PAGE_SIZE;
> + size -= PAGE_SIZE;
> + }
> +
> + spin_unlock(&heap_lock);
> +}
> +
> +void *alloc_page(void)
> +{
> + void *p;
> +
> + spin_lock(&heap_lock);
> +
> + if (!heap_free_head)
> + return NULL;
> +
> + p = heap_free_head;
> + heap_free_head = *(void **)heap_free_head;
> +
> + spin_unlock(&heap_lock);
> +
> + return p;
> +}
> +
> +void free_page(void *page)
> +{
> + spin_lock(&heap_lock);
> + *(void **)page = heap_free_head;
> + heap_free_head = page;
> + spin_unlock(&heap_lock);
> +}
> +
> static void *early_malloc(size_t size)
> {
> phys_addr_t addr = phys_alloc_aligned_safe(size,
> diff --git a/lib/alloc.h b/lib/alloc.h
> index bd3c4e8ff3f6..a37330b3088a 100644
> --- a/lib/alloc.h
> +++ b/lib/alloc.h
> @@ -118,4 +118,14 @@ extern phys_addr_t phys_zalloc(phys_addr_t size);
> */
> extern void phys_alloc_show(void);
>
> +/*
> + * Heap page allocator
> + *
> + * After initializing with heap_init, {alloc,free}_page can be used
> + * to easily manage pages.
> + */
> +extern void heap_init(void *start, size_t size);
> +extern void *alloc_page(void);
> +extern void free_page(void *page);
> +
> #endif /* _ALLOC_H_ */
> diff --git a/lib/x86/vm.c b/lib/x86/vm.c
> index baea17e7f475..4e399f80dd31 100644
> --- a/lib/x86/vm.c
> +++ b/lib/x86/vm.c
> @@ -1,56 +1,12 @@
> #include "fwcfg.h"
> #include "vm.h"
> #include "libcflat.h"
> +#include "alloc.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 NULL;
> -
> - p = free;
> - free = *(void **)free;
> -
> - spin_unlock(&heap_lock);
> -
> - return p;
> -}
> -
> -void free_page(void *page)
> -{
> - spin_lock(&heap_lock);
> - *(void **)page = free;
> - free = page;
> - spin_unlock(&heap_lock);
> -}
> -
> extern char edata;
> static unsigned long end_of_memory;
>
> @@ -170,7 +126,7 @@ void setup_vm()
> {
> assert(!end_of_memory);
> end_of_memory = fwcfg_get_u64(FW_CFG_RAM_SIZE);
> - free_memory(&edata, end_of_memory - (unsigned long)&edata);
> + heap_init(&edata, end_of_memory - (unsigned long)&edata);
> setup_mmu(end_of_memory);
> }
>
> diff --git a/x86/Makefile.common b/x86/Makefile.common
> index 356d879a986b..88038e41af60 100644
> --- a/x86/Makefile.common
> +++ b/x86/Makefile.common
> @@ -3,6 +3,7 @@
> all: test_cases
>
> cflatobjs += lib/pci.o
> +cflatobjs += lib/alloc.o
> cflatobjs += lib/x86/io.o
> cflatobjs += lib/x86/smp.o
> cflatobjs += lib/x86/vm.o
>
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