File 0005-kern-efi-mm-Implement-runtime-addition-of-pages.patch of Package grub2

From 3a2119e11b9c216f3b008a2c61aca52b91ad7547 Mon Sep 17 00:00:00 2001
From: Patrick Steinhardt <ps@pks.im>
Date: Thu, 21 Apr 2022 15:24:22 +1000
Subject: [PATCH 5/5] kern/efi/mm: Implement runtime addition of pages

Adjust the interface of grub_efi_mm_add_regions() to take a set of
GRUB_MM_ADD_REGION_* flags, which most notably is currently only the
GRUB_MM_ADD_REGION_CONSECUTIVE flag. This allows us to set the function
up as callback for the memory subsystem and have it call out to us in
case there's not enough pages available in the current heap.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Tested-by: Patrick Steinhardt <ps@pks.im>
---
 grub-core/kern/efi/mm.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/grub-core/kern/efi/mm.c b/grub-core/kern/efi/mm.c
index 45ea6d5..48380d3 100644
--- a/grub-core/kern/efi/mm.c
+++ b/grub-core/kern/efi/mm.c
@@ -518,7 +518,8 @@ static grub_err_t
 add_memory_regions (grub_efi_memory_descriptor_t *memory_map,
 		    grub_efi_uintn_t desc_size,
 		    grub_efi_memory_descriptor_t *memory_map_end,
-		    grub_efi_uint64_t required_pages)
+		    grub_efi_uint64_t required_pages,
+		    unsigned int flags)
 {
   grub_efi_memory_descriptor_t *desc;
 
@@ -532,6 +533,10 @@ add_memory_regions (grub_efi_memory_descriptor_t *memory_map,
 
       start = desc->physical_start;
       pages = desc->num_pages;
+
+      if (pages < required_pages && (flags & GRUB_MM_ADD_REGION_CONSECUTIVE))
+	continue;
+
       if (pages > required_pages)
 	{
 	  start += PAGES_TO_BYTES (pages - required_pages);
@@ -597,7 +602,7 @@ print_memory_map (grub_efi_memory_descriptor_t *memory_map,
 #endif
 
 static grub_err_t
-grub_efi_mm_add_regions (grub_size_t required_bytes)
+grub_efi_mm_add_regions (grub_size_t required_bytes, unsigned int flags)
 {
   grub_efi_memory_descriptor_t *memory_map;
   grub_efi_memory_descriptor_t *memory_map_end;
@@ -652,7 +657,8 @@ grub_efi_mm_add_regions (grub_size_t required_bytes)
   /* Allocate memory regions for GRUB's memory management.  */
   err = add_memory_regions (filtered_memory_map, desc_size,
 			    filtered_memory_map_end,
-			    BYTES_TO_PAGES (required_bytes));
+			    BYTES_TO_PAGES (required_bytes),
+			    flags);
   if (err != GRUB_ERR_NONE)
     return err;
 
@@ -679,8 +685,9 @@ grub_efi_mm_add_regions (grub_size_t required_bytes)
 void
 grub_efi_mm_init (void)
 {
-  if (grub_efi_mm_add_regions (DEFAULT_HEAP_SIZE) != GRUB_ERR_NONE)
+  if (grub_efi_mm_add_regions (DEFAULT_HEAP_SIZE, GRUB_MM_ADD_REGION_NONE) != GRUB_ERR_NONE)
     grub_fatal ("%s", grub_errmsg);
+  grub_mm_add_region_fn = grub_efi_mm_add_regions;
 }
 
 #if defined (__aarch64__) || defined (__arm__) || defined (__riscv)
-- 
2.35.3