[kvm-unit-tests PATCH v2 14/18] arm64: Add memregions_efi_init

Andrew Jones
2024-02-27T19:22:13Z

Provide a memregions function which initialized memregions from an
EFI memory map. Add a new memregions flag (MR_F_PERSISTENT) for
EFI_PERSISTENT_MEMORY since that type should not be reserved, but it
should also be distinct from conventional memory. The function also
points out the largest conventional memory region by returning a
pointer to it in the freemem parameter. Immediately apply this
function to arm64's efi_mem_init(). riscv will make use of it as well.

Signed-off-by: Andrew Jones <andrew.jones@linux.dev>
---
lib/arm/setup.c | 76 ++++++++----------------------------------------
lib/memregions.c | 51 ++++++++++++++++++++++++++++++++
lib/memregions.h | 6 ++++
3 files changed, 69 insertions(+), 64 deletions(-)

diff --git a/lib/arm/setup.c b/lib/arm/setup.c
index 631597b343f1..521928186fb0 100644
--- a/lib/arm/setup.c
+++ b/lib/arm/setup.c
@@ -295,58 +295,13 @@ static efi_status_t setup_rsdp(efi_bootinfo_t *efi_bootinfo)

static efi_status_t efi_mem_init(efi_bootinfo_t *efi_bootinfo)
{
- int i;
- unsigned long free_mem_pages = 0;
- unsigned long free_mem_start = 0;
- struct efi_boot_memmap *map = &(efi_bootinfo->mem_map);
- efi_memory_desc_t *buffer = *map->map;
- efi_memory_desc_t *d = NULL;
- struct mem_region r, *code, *data;
- const void *fdt = efi_bootinfo->fdt;
-
- /*
- * Record 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.
- */
- for (i = 0; i < *(map->map_size); i += *(map->desc_size)) {
- d = (efi_memory_desc_t *)(&((u8 *)buffer)[i]);
-
- r.start = d->phys_addr;
- r.end = d->phys_addr + d->num_pages * EFI_PAGE_SIZE;
- r.flags = 0;
-
- switch (d->type) {
- case EFI_RESERVED_TYPE:
- case EFI_LOADER_DATA:
- case EFI_BOOT_SERVICES_CODE:
- case EFI_BOOT_SERVICES_DATA:
- case EFI_RUNTIME_SERVICES_CODE:
- case EFI_RUNTIME_SERVICES_DATA:
- case EFI_UNUSABLE_MEMORY:
- case EFI_ACPI_RECLAIM_MEMORY:
- case EFI_ACPI_MEMORY_NVS:
- case EFI_PAL_CODE:
- r.flags = MR_F_RESERVED;
- break;
- case EFI_MEMORY_MAPPED_IO:
- case EFI_MEMORY_MAPPED_IO_PORT_SPACE:
- r.flags = MR_F_IO;
- break;
- case EFI_LOADER_CODE:
- r.flags = MR_F_CODE;
- break;
- case EFI_CONVENTIONAL_MEMORY:
- if (free_mem_pages < d->num_pages) {
- free_mem_pages = d->num_pages;
- free_mem_start = d->phys_addr;
- }
- break;
- }
+ struct mem_region *freemem_mr = NULL, *code, *data;
+ phys_addr_t freemem_start;
+ void *freemem;

- memregions_add(&r);
- }
+ memregions_efi_init(&efi_bootinfo->mem_map, &freemem_mr);
+ if (!freemem_mr)
+ return EFI_OUT_OF_RESOURCES;

memregions_split((unsigned long)&_etext, &code, &data);
assert(code && (code->flags & MR_F_CODE));
@@ -366,24 +321,17 @@ static efi_status_t efi_mem_init(efi_bootinfo_t *efi_bootinfo)
}
__phys_end &= PHYS_MASK;

- if (efi_bootinfo->fdt_valid) {
- unsigned long old_start = free_mem_start;
- void *freemem = (void *)free_mem_start;
+ freemem = (void *)PAGE_ALIGN(freemem_mr->start);

- freemem_push_fdt(&freemem, fdt);
+ if (efi_bootinfo->fdt_valid)
+ freemem_push_fdt(&freemem, efi_bootinfo->fdt);

- free_mem_start = ALIGN((unsigned long)freemem, EFI_PAGE_SIZE);
- free_mem_pages = (free_mem_start - old_start) >> EFI_PAGE_SHIFT;
- }
+ freemem_start = PAGE_ALIGN((unsigned long)freemem);
+ assert(sizeof(long) == 8 || freemem_start < (3ul << 30));

asm_mmu_disable();

- if (free_mem_pages == 0)
- return EFI_OUT_OF_RESOURCES;
-
- assert(sizeof(long) == 8 || free_mem_start < (3ul << 30));
-
- mem_allocator_init(free_mem_start, free_mem_start + (free_mem_pages << EFI_PAGE_SHIFT));
+ mem_allocator_init(freemem_start, freemem_mr->end);

return EFI_SUCCESS;
}
diff --git a/lib/memregions.c b/lib/memregions.c
index 96de86b27333..9cdbb639ab62 100644
--- a/lib/memregions.c
+++ b/lib/memregions.c
@@ -80,3 +80,54 @@ void memregions_add_dt_regions(size_t max_nr)
});
}
}
+
+#ifdef CONFIG_EFI
+/*
+ * Add memory regions based on the EFI memory map. Also set a pointer to the
+ * memory region which corresponds to the largest EFI_CONVENTIONAL_MEMORY
+ * region, as that region is the largest free, continuous region, making it
+ * a good choice for the memory allocator.
+ */
+void memregions_efi_init(struct efi_boot_memmap *mem_map,
+ struct mem_region **freemem)
+{
+ u8 *buffer = (u8 *)*mem_map->map;
+ u64 freemem_pages = 0;
+
+ *freemem = NULL;
+
+ for (int i = 0; i < *mem_map->map_size; i += *mem_map->desc_size) {
+ efi_memory_desc_t *d = (efi_memory_desc_t *)&buffer[i];
+ struct mem_region r = {
+ .start = d->phys_addr,
+ .end = d->phys_addr + d->num_pages * EFI_PAGE_SIZE,
+ .flags = 0,
+ };
+
+ switch (d->type) {
+ case EFI_MEMORY_MAPPED_IO:
+ case EFI_MEMORY_MAPPED_IO_PORT_SPACE:
+ r.flags = MR_F_IO;
+ break;
+ case EFI_LOADER_CODE:
+ r.flags = MR_F_CODE;
+ break;
+ case EFI_PERSISTENT_MEMORY:
+ r.flags = MR_F_PERSISTENT;
+ break;
+ case EFI_CONVENTIONAL_MEMORY:
+ if (freemem_pages < d->num_pages) {
+ freemem_pages = d->num_pages;
+ *freemem = memregions_add(&r);
+ continue;
+ }
+ break;
+ default:
+ r.flags = MR_F_RESERVED;
+ break;
+ }
+
+ memregions_add(&r);
+ }
+}
+#endif /* CONFIG_EFI */
diff --git a/lib/memregions.h b/lib/memregions.h
index 9a8e33182fe5..1600530ad7bf 100644
--- a/lib/memregions.h
+++ b/lib/memregions.h
@@ -9,6 +9,7 @@
#define MR_F_IO BIT(0)
#define MR_F_CODE BIT(1)
#define MR_F_RESERVED BIT(2)
+#define MR_F_PERSISTENT BIT(3)
#define MR_F_UNKNOWN BIT(31)

struct mem_region {
@@ -26,4 +27,9 @@ uint32_t memregions_get_flags(phys_addr_t paddr);
void memregions_split(phys_addr_t addr, struct mem_region **r1, struct mem_region **r2);
void memregions_add_dt_regions(size_t max_nr);

+#ifdef CONFIG_EFI
+#include <efi.h>
+void memregions_efi_init(struct efi_boot_memmap *mem_map, struct mem_region **freemem);
+#endif
+
#endif /* _MEMREGIONS_H_ */
--
2.43.0