On Fri, Aug 27, 2021 at 03:12:12AM +0000, Zixuan Wang wrote:
> KVM-Unit-Tests library implements a memory allocator which requires
> two arguments to set up (See `lib/alloc_phys.c:phys_alloc_init()` for
> more details):
> 1. A base (start) physical address
> 2. Size of available memory for allocation
>
> To get this memory info, we scan all the memory regions returned by
> `LibMemoryMap()`, find out the largest free memory region and use it for
> memory allocation.
>
> After retrieving this memory info, we call `ExitBootServices` so that
> KVM-Unit-Tests has full control of the machine, and UEFI will not touch
> the memory after this point.
>
> Starting from this commit, `x86/hypercall.c` test case can run in UEFI
> and generates the same output as in Seabios.
>
> Co-developed-by: Varad Gautam <varad.gautam@xxxxxxxx>
> Signed-off-by: Varad Gautam <varad.gautam@xxxxxxxx>
> Signed-off-by: Zixuan Wang <zixuanwang@xxxxxxxxxx>
> ---
> lib/efi.c | 28 +++++++++++++---
> lib/efi.h | 2 +-
> lib/x86/asm/setup.h | 16 +++++++++-
> lib/x86/setup.c | 78 ++++++++++++++++++++++++++++++++++++++++++++-
> 4 files changed, 116 insertions(+), 8 deletions(-)
>
> diff --git a/lib/efi.c b/lib/efi.c
> index 99307db..b7a69d3 100644
> --- a/lib/efi.c
> +++ b/lib/efi.c
> @@ -31,9 +31,10 @@ efi_status_t efi_get_memory_map(struct efi_boot_memmap *map)
> efi_memory_desc_t *m = NULL;
> efi_status_t status;
> unsigned long key = 0, map_size = 0, desc_size = 0;
> + u32 desc_ver;
>
> status = efi_bs_call(get_memory_map, &map_size,
> - NULL, &key, &desc_size, NULL);
> + NULL, &key, &desc_size, &desc_ver);
> if (status != EFI_BUFFER_TOO_SMALL || map_size == 0)
> goto out;
>
> @@ -48,12 +49,13 @@ efi_status_t efi_get_memory_map(struct efi_boot_memmap *map)
>
> /* Get the map. */
> status = efi_bs_call(get_memory_map, &map_size,
> - m, &key, &desc_size, NULL);
> + m, &key, &desc_size, &desc_ver);
> if (status != EFI_SUCCESS) {
> efi_free_pool(m);
> goto out;
> }
>
> + *map->desc_ver = desc_ver;
> *map->desc_size = desc_size;
> *map->map_size = map_size;
> *map->key_ptr = key;
> @@ -62,18 +64,34 @@ out:
> return status;
> }
>
> -efi_status_t efi_exit_boot_services(void *handle, struct efi_boot_memmap *map)
> +efi_status_t efi_exit_boot_services(void *handle, unsigned long mapkey)
> {
> - return efi_bs_call(exit_boot_services, handle, *map->key_ptr);
> + return efi_bs_call(exit_boot_services, handle, mapkey);
> }
>
> efi_status_t efi_main(efi_handle_t handle, efi_system_table_t *sys_tab)
> {
> int ret;
> + unsigned long mapkey = 0;
> + efi_status_t status;
> + efi_bootinfo_t efi_bootinfo;
>
> efi_system_table = sys_tab;
>
> - setup_efi();
> + setup_efi_bootinfo(&efi_bootinfo);
> + status = setup_efi_pre_boot(&mapkey, &efi_bootinfo);
> + if (status != EFI_SUCCESS) {
> + printf("Failed to set up before ExitBootServices, exiting.\n");
> + return status;
> + }
> +
> + status = efi_exit_boot_services(handle, mapkey);
> + if (status != EFI_SUCCESS) {
> + printf("Failed to exit boot services\n");
> + return status;
> + }
> +
> + setup_efi(&efi_bootinfo);
> ret = main(__argc, __argv, __environ);
>
> /* Shutdown the guest VM */
> diff --git a/lib/efi.h b/lib/efi.h
> index 60cdb6f..2d3772c 100644
> --- a/lib/efi.h
> +++ b/lib/efi.h
> @@ -11,7 +11,7 @@
>
> efi_status_t _relocate(long ldbase, Elf64_Dyn *dyn, efi_handle_t handle, efi_system_table_t *sys_tab);
> efi_status_t efi_get_memory_map(struct efi_boot_memmap *map);
> -efi_status_t efi_exit_boot_services(void *handle, struct efi_boot_memmap *map);
> +efi_status_t efi_exit_boot_services(void *handle, unsigned long mapkey);
> efi_status_t efi_main(efi_handle_t handle, efi_system_table_t *sys_tab);
>
> #endif /* _EFI_H_ */
> diff --git a/lib/x86/asm/setup.h b/lib/x86/asm/setup.h
> index eb1cf73..8ff31ef 100644
> --- a/lib/x86/asm/setup.h
> +++ b/lib/x86/asm/setup.h
> @@ -4,8 +4,22 @@
> #ifdef TARGET_EFI
> #include "x86/apic.h"
> #include "x86/smp.h"
> +#include "efi.h"
>
> -void setup_efi(void);
> +/*
> + * efi_bootinfo_t: stores EFI-related machine info retrieved by
> + * setup_efi_pre_boot(), and is then used by setup_efi(). setup_efi() cannot
> + * retrieve this info as it is called after ExitBootServices and thus some EFI
> + * resources are not available.
> + */
> +typedef struct {
> + phys_addr_t free_mem_start;
> + phys_addr_t free_mem_size;
> +} efi_bootinfo_t;
> +
> +void setup_efi_bootinfo(efi_bootinfo_t *efi_bootinfo);
> +void setup_efi(efi_bootinfo_t *efi_bootinfo);
> +efi_status_t setup_efi_pre_boot(unsigned long *mapkey, efi_bootinfo_t *efi_bootinfo);
> #endif /* TARGET_EFI */
>
> #endif /* _X86_ASM_SETUP_H_ */
> diff --git a/lib/x86/setup.c b/lib/x86/setup.c
> index 0a065fe..a49e0d4 100644
> --- a/lib/x86/setup.c
> +++ b/lib/x86/setup.c
> @@ -131,6 +131,81 @@ extern phys_addr_t ring0stacktop;
> extern gdt_entry_t gdt64[];
> extern size_t ring0stacksize;
>
> +void setup_efi_bootinfo(efi_bootinfo_t *efi_bootinfo)
> +{
> + efi_bootinfo->free_mem_size = 0;
> + efi_bootinfo->free_mem_start = 0;
> +}
> +
> +static efi_status_t setup_pre_boot_memory(unsigned long *mapkey, efi_bootinfo_t *efi_bootinfo)
> +{
> + int i;
> + unsigned long free_mem_total_pages;
> + efi_status_t status;
> + struct efi_boot_memmap map;
> + efi_memory_desc_t *buffer, *d;
> + unsigned long map_size, desc_size, buff_size;
> + u32 desc_ver;
> +
> + map.map = &buffer;
> + map.map_size = &map_size;
> + map.desc_size = &desc_size;
> + map.desc_ver = &desc_ver;
> + map.buff_size = &buff_size;
> + map.key_ptr = mapkey;
> +
> + status = efi_get_memory_map(&map);
> + if (status != EFI_SUCCESS) {
> + return status;
> + }
> +
> + /*
> + * The 'buffer' contains multiple descriptors that describe memory
> + * regions maintained by UEFI. This code records the largest free
> + * EFI_CONVENTIONAL_MEMORY region which will be used to set up the
> + * memory allocator, so that the memory allocator can work in the
> + * largest free continuous memory region.
> + */
> + free_mem_total_pages = 0;
> + for (i = 0; i < map_size; i += desc_size) {
> + d = (efi_memory_desc_t *)(&((u8 *)buffer)[i]);
> + if (d->type == EFI_CONVENTIONAL_MEMORY) {
> + if (free_mem_total_pages < d->num_pages) {
> + free_mem_total_pages = d->num_pages;
> + efi_bootinfo->free_mem_size = free_mem_total_pages << EFI_PAGE_SHIFT;
> + efi_bootinfo->free_mem_start = d->phys_addr;
> + }
> + }
> + }
> +
> + if (efi_bootinfo->free_mem_size == 0) {
> + return EFI_OUT_OF_RESOURCES;
> + }
> +
> + return EFI_SUCCESS;
> +}
> +
> +efi_status_t setup_efi_pre_boot(unsigned long *mapkey, efi_bootinfo_t *efi_bootinfo)
> +{
> + efi_status_t status;
> +
> + status = setup_pre_boot_memory(mapkey, efi_bootinfo);
> + if (status != EFI_SUCCESS) {
> + printf("setup_pre_boot_memory() failed: ");
> + switch (status) {
> + case EFI_OUT_OF_RESOURCES:
> + printf("No free memory region\n");
> + break;
> + default:
> + printf("Unknown error\n");
> + break;
> + }
> + return status;
> + }
> +
> + return EFI_SUCCESS;
> +}
> +
> static void setup_gdt_tss(void)
> {
> gdt_entry_t *tss_lo, *tss_hi;
> @@ -169,7 +244,7 @@ static void setup_gdt_tss(void)
> load_gdt_tss(tss_offset);
> }
>
> -void setup_efi(void)
> +void setup_efi(efi_bootinfo_t *efi_bootinfo)
> {
> reset_apic();
> setup_gdt_tss();
> @@ -179,6 +254,7 @@ void setup_efi(void)
> enable_apic();
> enable_x2apic();
> smp_init();
> + phys_alloc_init(efi_bootinfo->free_mem_start, efi_bootinfo->free_mem_size);
> }
>
> #endif /* TARGET_EFI */
> --
> 2.33.0.259.gc128427fd7-goog
>
How about just getting the memory map (efi_boot_memmap) and then exiting
boot services in arch-neutral code and then have arch-specific code decide
what to do with the memory map?
Thanks,
drew
