per-image buffer

1 files changed, 16 insertions, 47 deletions

diff --git a/loader/loader_efi.c b/loader/loader_efi.c
index b56ebb9..5e238f6 100644
--- a/loader/loader_efi.c
+++ b/loader/loader_efi.c
@@ -11,25 +11,20 @@
 struct system_buffer
 {
     EFI_PHYSICAL_ADDRESS base;
-    EFI_PHYSICAL_ADDRESS head;
-    UINTN pages;
+    UINTN size;
 };
 
 struct system_image
 {
+    struct system_buffer buffer;
     EFI_FILE_PROTOCOL *file;
-    EFI_PHYSICAL_ADDRESS base;
-    UINTN size;
     Elf64_Ehdr ehdr;
     Elf64_Phdr *phdrs;
 };
 
 static struct system_buffer get_system_buffer(size_t size);
-static EFI_PHYSICAL_ADDRESS system_allocate(struct system_buffer *buffer,
-                                            size_t size);
 static struct system_image *open_system_image(CHAR16 *path);
-static bool load_system_image(struct system_buffer *buffer,
-                              struct system_image *image);
+static bool load_system_image(struct system_image *image);
 static struct efi_memory_map_data *get_memory_map_data(void);
 static struct efi_framebuffer_data *get_framebuffer_data(void);
 static void *get_acpi_rsdp(void);
@@ -38,14 +33,13 @@ void loader_main(void)
 {
     struct efi_boot_data data;
 
-    struct system_buffer kernel_buffer = get_system_buffer(0x400000);
     struct system_image *kernel_image = open_system_image(kernel_path);
 
-    if (load_system_image(&kernel_buffer, kernel_image))
+    if (load_system_image(kernel_image))
     {
         Print(L"loaded kernel image at base %16.0x size %d bytes\r\n",
-              kernel_image->base,
-              kernel_image->size);
+              kernel_image->buffer.base,
+              kernel_image->buffer.size);
     }
     else
     {
@@ -54,7 +48,7 @@ void loader_main(void)
     }
 
     kernel_entry_func kernel_entry;
-    kernel_entry = (kernel_entry_func)(kernel_image->base +
+    kernel_entry = (kernel_entry_func)(kernel_image->buffer.base +
                                        kernel_image->ehdr.e_entry);
 
     data.system_table = e_st;
@@ -74,45 +68,26 @@ void loader_main(void)
     kernel_entry(&data);
 }
 
-static struct system_buffer get_system_buffer(size_t size)
+static struct system_buffer get_system_buffer(UINTN size)
 {
     EFI_STATUS status;
     struct system_buffer buffer;
 
-    buffer.pages = EFI_SIZE_TO_PAGES(size);
-
     status = e_bs->AllocatePages(AllocateAnyPages,
                                  SystemMemoryType,
-                                 buffer.pages,
+                                 EFI_SIZE_TO_PAGES(size),
                                  &buffer.base);
 
-    if (!EFI_ERROR(status))
-    {
-        buffer.head = buffer.base;
-    }
-    else
+    if (EFI_ERROR(status))
     {
         Print(L"error allocating system buffer: %r\r\n", status);
         buffer.base = 0;
-        buffer.pages = 0;
+        buffer.size = 0;
     }
 
     return buffer;
 }
 
-static EFI_PHYSICAL_ADDRESS system_allocate(struct system_buffer *buffer,
-                                            UINTN size)
-{
-    if (EFI_SIZE_TO_PAGES(buffer->head + size - buffer->base) < buffer->pages)
-    {
-        EFI_PHYSICAL_ADDRESS result = buffer->head;
-        buffer->head += size;
-        return result;
-    }
-
-    return 0;
-}
-
 static bool validate_image(Elf64_Ehdr *ehdr)
 {
     if (ehdr->e_ident[EI_MAG0] != ELFMAG0 ||
@@ -221,9 +196,6 @@ static struct system_image *open_system_image(CHAR16 *path)
         goto failure;
     }
 
-    image->size = get_image_size(image);
-    image->base = 0;
-
     return image;
 
 failure:
@@ -231,18 +203,16 @@ failure:
     return NULL;
 }
 
-static bool load_system_image(struct system_buffer *buffer,
-                              struct system_image *image)
+static bool load_system_image(struct system_image *image)
 {
-    image->base = system_allocate(buffer, image->size);
+    image->buffer = get_system_buffer(get_image_size(image));
 
-    if (!image->base)
+    if (!image->buffer.base)
     {
-        Print(L"system buffer is full\r\n");
         return false;
     }
 
-    e_bs->SetMem((VOID *)image->base, image->size, 0);
+    e_bs->SetMem((VOID *)image->buffer.base, image->buffer.size, 0);
 
     Elf64_Ehdr *ehdr = &image->ehdr;
     Elf64_Phdr *phdrs = image->phdrs;
@@ -260,13 +230,12 @@ static bool load_system_image(struct system_buffer *buffer,
                       phdrs[i].p_offset,
                       phdrs[i].p_memsz);
 
-                void *segment = (void *)(image->base + phdrs[i].p_paddr);
+                void *segment = (void *)(image->buffer.base + phdrs[i].p_paddr);
                 UINTN segment_size = phdrs[i].p_filesz;
 
                 image->file->SetPosition(image->file, phdrs[i].p_offset);
                 status = image->file->Read(image->file, &segment_size, segment);
                 break;
-
             default:
                 continue;
         }