multiboot2: Add mb2_alloc() for quirky allocation locations

common/lib/elf.c

@@ -308,22 +308,7 @@ struct elf_section_hdr_info* elf64_section_hdr_info(uint8_t *elf) {
     info->section_entry_size = hdr.shdr_size;
     info->section_hdr_size = info->num * info->section_entry_size;
     info->str_section_idx = hdr.shstrndx;
-    info->section_hdrs = ext_mem_alloc(info->section_hdr_size);
+    info->section_offset = hdr.shoff;
-
-    memcpy(info->section_hdrs, elf + (hdr.shoff), info->section_hdr_size);
-
-    for (size_t i = 0; i < info->num; i++) {
-        struct elf64_shdr *shdr = info->section_hdrs + i * hdr.shdr_size;
-
-        if (shdr->sh_addr != 0 || shdr->sh_size == 0) {
-            continue;
-        }
-
-        void *section = conv_mem_alloc(shdr->sh_size);
-        memcpy(section, elf + shdr->sh_offset, shdr->sh_size);
-
-        shdr->sh_addr = (uintptr_t)section;
-    }
 
     return info;
 }
@@ -340,22 +325,7 @@ struct elf_section_hdr_info* elf32_section_hdr_info(uint8_t *elf) {
     info->section_entry_size = hdr.shdr_size;
     info->section_hdr_size = info->num * info->section_entry_size;
     info->str_section_idx = hdr.shstrndx;
-    info->section_hdrs = ext_mem_alloc(info->section_hdr_size);
+    info->section_offset = hdr.shoff;
-
-    memcpy(info->section_hdrs, elf + (hdr.shoff), info->section_hdr_size);
-
-    for (size_t i = 0; i < info->num; i++) {
-        struct elf32_shdr *shdr = info->section_hdrs + i * hdr.shdr_size;
-
-        if (shdr->sh_addr != 0 || shdr->sh_size == 0) {
-            continue;
-        }
-
-        void *section = conv_mem_alloc(shdr->sh_size);
-        memcpy(section, elf + shdr->sh_offset, shdr->sh_size);
-
-        shdr->sh_addr = (uintptr_t)section;
-    }
 
     return info;
 }

common/lib/elf.h

@@ -22,7 +22,7 @@ struct elf_section_hdr_info {
     uint32_t section_entry_size;
     uint32_t str_section_idx;
     uint32_t num;
-    void* section_hdrs;
+    uint32_t section_offset;
 };
 
 int elf_bits(uint8_t *elf);

common/protos/multiboot2.c

@@ -55,6 +55,20 @@ static size_t get_multiboot2_info_size(
 
 #define append_tag(P, TAG) ({ (P) += ALIGN_UP((TAG)->size, MULTIBOOT_TAG_ALIGN); })
 
+static uint32_t kernel_top;
+
+static void *mb2_alloc(size_t size) {
+    void *ret = (void *)(uintptr_t)ALIGN_UP(kernel_top, 4096);
+
+    while (!memmap_alloc_range((uintptr_t)ret, size, MEMMAP_KERNEL_AND_MODULES,
+                               true, false, false, false)) {
+        ret += 0x200000;
+    }
+
+    kernel_top = (uintptr_t)ret + size;
+    return ret;
+}
+
 bool multiboot2_load(char *config, char* cmdline) {
     struct file_handle *kernel_file;
 
@@ -175,8 +189,6 @@ bool multiboot2_load(char *config, char* cmdline) {
         }
     }
 
-    uint32_t kernel_top;
-
     if (addresstag != NULL) {
         if (addresstag->load_addr > addresstag->header_addr)
             panic(true, "multiboot2: Illegal load address");
@@ -284,6 +296,42 @@ bool multiboot2_load(char *config, char* cmdline) {
     struct multiboot2_start_tag *mbi_start = (struct multiboot2_start_tag *)mb2_info;
     info_idx += sizeof(struct multiboot2_start_tag);
 
+    //////////////////////////////////////////////
+    // Create ELF info tag
+    //////////////////////////////////////////////
+    if (section_hdr_info == NULL) {
+        if (is_elf_info_requested) {
+            panic(true, "multiboot2: Cannot return ELF file information");
+        }
+    } else {
+        uint32_t size = sizeof(struct multiboot_tag_elf_sections) + section_hdr_info->section_hdr_size;
+        struct multiboot_tag_elf_sections *tag = (struct multiboot_tag_elf_sections*)(mb2_info + info_idx);
+
+        tag->type = MULTIBOOT_TAG_TYPE_ELF_SECTIONS;
+        tag->size = size;
+
+        tag->num = section_hdr_info->num;
+        tag->entsize = section_hdr_info->section_entry_size;
+        tag->shndx = section_hdr_info->str_section_idx;
+
+        memcpy(tag->sections, kernel + section_hdr_info->section_offset, section_hdr_info->section_hdr_size);
+
+        for (size_t i = 0; i < section_hdr_info->num; i++) {
+            struct elf64_shdr *shdr = (void *)kernel + section_hdr_info->section_offset + i * section_hdr_info->section_entry_size;
+
+            if (shdr->sh_addr != 0 || shdr->sh_size == 0) {
+                continue;
+            }
+
+            void *section = mb2_alloc(shdr->sh_size);
+            memcpy(section, kernel + shdr->sh_offset, shdr->sh_size);
+
+            shdr->sh_addr = (uintptr_t)section;
+        }
+
+        append_tag(info_idx, tag);
+    }
+
     //////////////////////////////////////////////
     // Create modules tag
     //////////////////////////////////////////////
@@ -298,19 +346,14 @@ bool multiboot2_load(char *config, char* cmdline) {
         if ((f = uri_open(module_path)) == NULL)
             panic(true, "multiboot2: Failed to open module with path `%s`. Is the path correct?", module_path);
 
-        void *module_addr = (void *)(uintptr_t)ALIGN_UP(kernel_top, 4096);
 
         // Module commandline can be null, so we guard against that and make the
         // string "".
         char *module_cmdline = conf_tuple.value2;
         if (!module_cmdline) module_cmdline = "";
 
-        while (!memmap_alloc_range((uintptr_t)module_addr, f->size, MEMMAP_KERNEL_AND_MODULES,
+        void *module_addr = mb2_alloc(f->size);
-                                   true, false, false, false)) {
-            module_addr += 0x200000;
-        }
 
-        kernel_top = (uintptr_t)module_addr + f->size;
         fread(f, module_addr, 0, f->size);
 
         struct multiboot_tag_module *module_tag = (struct multiboot_tag_module *)(mb2_info + info_idx);
@@ -548,30 +591,6 @@ bool multiboot2_load(char *config, char* cmdline) {
     }
 #endif
 
-    //////////////////////////////////////////////
-    // Create ELF info tag
-    //////////////////////////////////////////////
-    {
-        if (section_hdr_info == NULL) {
-            if (is_elf_info_requested) {
-                panic(true, "multiboot2: Cannot return ELF file information");
-            }
-        } else {
-            uint32_t size = sizeof(struct multiboot_tag_elf_sections) + section_hdr_info->section_hdr_size;
-            struct multiboot_tag_elf_sections *tag = (struct multiboot_tag_elf_sections*)(mb2_info + info_idx);
-
-            tag->type = MULTIBOOT_TAG_TYPE_ELF_SECTIONS;
-            tag->size = size;
-
-            tag->num = section_hdr_info->num;
-            tag->entsize = section_hdr_info->section_entry_size;
-            tag->shndx = section_hdr_info->str_section_idx;
-
-            memcpy(tag->sections, section_hdr_info->section_hdrs, section_hdr_info->section_hdr_size);
-            append_tag(info_idx, tag);
-        }
-    }
-
 #if uefi == 1
     efi_exit_boot_services();
 #endif