diff mbox series

[v5,2/6] efi_loader: add a function to remove memory from the EFI map

Message ID 20250227111519.45787-3-sughosh.ganu@linaro.org
State New
Headers show
Series Add pmem node for preserving distro ISO's | expand

Commit Message

Sughosh Ganu Feb. 27, 2025, 11:15 a.m. UTC
From: Ilias Apalodimas <ilias.apalodimas@linaro.org>

With upcoming changes supporting pmem nodes, we need to remove the
pmem area from the EFI memory map. Add a function to do that.

Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
---
Changes since V4:
* Rebase patch changes on top of the next branch

 include/efi_loader.h        | 18 ++++++++++++
 lib/efi_loader/efi_memory.c | 56 ++++++++++++++++++++++++++-----------
 2 files changed, 58 insertions(+), 16 deletions(-)
diff mbox series

Patch

diff --git a/include/efi_loader.h b/include/efi_loader.h
index 1d75d97ebbc..0ac00911598 100644
--- a/include/efi_loader.h
+++ b/include/efi_loader.h
@@ -852,6 +852,24 @@  efi_status_t efi_get_memory_map(efi_uintn_t *memory_map_size,
 /* Adds a range into the EFI memory map */
 efi_status_t efi_add_memory_map(u64 start, u64 size, int memory_type);
 
+/**
+ * efi_update_memory_map() - update the memory map by adding/removing pages
+ *
+ * @start:			start address, must be a multiple of
+ *				EFI_PAGE_SIZE
+ * @pages:			number of pages to add
+ * @memory_type:		type of memory added
+ * @overlap_conventional:	region may only overlap free(conventional)
+ *				memory
+ * @remove:			remove memory map
+ * Return:			status code
+ */
+efi_status_t efi_update_memory_map(u64 start, u64 pages, int memory_type,
+				   bool overlap_conventional, bool remove);
+
+/* Remove memory from the EFI memory map */
+efi_status_t efi_remove_memory_map(u64 start, u64 size, int memory_type);
+
 /* Called by board init to initialize the EFI drivers */
 efi_status_t efi_driver_init(void);
 /* Called when a block device is added */
diff --git a/lib/efi_loader/efi_memory.c b/lib/efi_loader/efi_memory.c
index 6d00b186250..3fec40b6de5 100644
--- a/lib/efi_loader/efi_memory.c
+++ b/lib/efi_loader/efi_memory.c
@@ -258,7 +258,7 @@  static s64 efi_mem_carve_out(struct efi_mem_list *map,
 }
 
 /**
- * efi_add_memory_map_pg() - add pages to the memory map
+ * efi_update_memory_map() - update the memory map by adding/removing pages
  *
  * @start:			start address, must be a multiple of
  *				EFI_PAGE_SIZE
@@ -266,12 +266,11 @@  static s64 efi_mem_carve_out(struct efi_mem_list *map,
  * @memory_type:		type of memory added
  * @overlap_conventional:	region may only overlap free(conventional)
  *				memory
+ * @remove:			remove memory map
  * Return:			status code
  */
-static
-efi_status_t efi_add_memory_map_pg(u64 start, u64 pages,
-				   int memory_type,
-				   bool overlap_conventional)
+efi_status_t efi_update_memory_map(u64 start, u64 pages, int memory_type,
+				   bool overlap_conventional, bool remove)
 {
 	struct efi_mem_list *lmem;
 	struct efi_mem_list *newlist;
@@ -279,9 +278,9 @@  efi_status_t efi_add_memory_map_pg(u64 start, u64 pages,
 	uint64_t carved_pages = 0;
 	struct efi_event *evt;
 
-	EFI_PRINT("%s: 0x%llx 0x%llx %d %s\n", __func__,
+	EFI_PRINT("%s: 0x%llx 0x%llx %d %s %s\n", __func__,
 		  start, pages, memory_type, overlap_conventional ?
-		  "yes" : "no");
+		  "yes" : "no", remove ? "remove" : "add");
 
 	if (memory_type >= EFI_MAX_MEMORY_TYPE)
 		return EFI_INVALID_PARAMETER;
@@ -364,7 +363,10 @@  efi_status_t efi_add_memory_map_pg(u64 start, u64 pages,
 	}
 
 	/* Add our new map */
-        list_add_tail(&newlist->link, &efi_mem);
+	if (!remove)
+		list_add_tail(&newlist->link, &efi_mem);
+	else
+		free(newlist);
 
 	/* And make sure memory is listed in descending order */
 	efi_mem_sort();
@@ -401,7 +403,29 @@  efi_status_t efi_add_memory_map(u64 start, u64 size, int memory_type)
 	pages = efi_size_in_pages(size + (start & EFI_PAGE_MASK));
 	start &= ~EFI_PAGE_MASK;
 
-	return efi_add_memory_map_pg(start, pages, memory_type, false);
+	return efi_update_memory_map(start, pages, memory_type, false, false);
+}
+
+/**
+ * efi_remove_memory_map() - remove memory area to the memory map
+ *
+ * @start:		start address of the memory area
+ * @size:		length in bytes of the memory area
+ * @memory_type:	type of memory removed
+ *
+ * Return:		status code
+ *
+ * This function automatically aligns the start and size of the memory area
+ * to EFI_PAGE_SIZE.
+ */
+efi_status_t efi_remove_memory_map(u64 start, u64 size, int memory_type)
+{
+	u64 pages;
+
+	pages = efi_size_in_pages(size + (start & EFI_PAGE_MASK));
+	start &= ~EFI_PAGE_MASK;
+
+	return efi_update_memory_map(start, pages, memory_type, false, true);
 }
 
 /**
@@ -502,7 +526,7 @@  efi_status_t efi_allocate_pages(enum efi_allocate_type type,
 
 	efi_addr = (u64)(uintptr_t)map_sysmem(addr, 0);
 	/* Reserve that map in our memory maps */
-	ret = efi_add_memory_map_pg(efi_addr, pages, memory_type, true);
+	ret = efi_update_memory_map(efi_addr, pages, memory_type, true, false);
 	if (ret != EFI_SUCCESS) {
 		/* Map would overlap, bail out */
 		lmb_free_flags(addr, (u64)pages << EFI_PAGE_SHIFT, flags);
@@ -823,8 +847,8 @@  static void add_u_boot_and_runtime(void)
 		       uboot_stack_size) & ~EFI_PAGE_MASK;
 	uboot_pages = ((uintptr_t)map_sysmem(gd->ram_top - 1, 0) -
 		       uboot_start + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT;
-	efi_add_memory_map_pg(uboot_start, uboot_pages, EFI_BOOT_SERVICES_CODE,
-			      false);
+	efi_update_memory_map(uboot_start, uboot_pages, EFI_BOOT_SERVICES_CODE,
+			      false, false);
 #if defined(__aarch64__)
 	/*
 	 * Runtime Services must be 64KiB aligned according to the
@@ -842,8 +866,8 @@  static void add_u_boot_and_runtime(void)
 	runtime_end = (uintptr_t)__efi_runtime_stop;
 	runtime_end = (runtime_end + runtime_mask) & ~runtime_mask;
 	runtime_pages = (runtime_end - runtime_start) >> EFI_PAGE_SHIFT;
-	efi_add_memory_map_pg(runtime_start, runtime_pages,
-			      EFI_RUNTIME_SERVICES_CODE, false);
+	efi_update_memory_map(runtime_start, runtime_pages,
+			      EFI_RUNTIME_SERVICES_CODE, false, false);
 }
 
 int efi_memory_init(void)
@@ -878,11 +902,11 @@  int efi_map_update_notify(phys_addr_t addr, phys_size_t size,
 	pages = efi_size_in_pages(size + (efi_addr & EFI_PAGE_MASK));
 	efi_addr &= ~EFI_PAGE_MASK;
 
-	status = efi_add_memory_map_pg(efi_addr, pages,
+	status = efi_update_memory_map(efi_addr, pages,
 				       op == LMB_MAP_OP_RESERVE ?
 				       EFI_BOOT_SERVICES_DATA :
 				       EFI_CONVENTIONAL_MEMORY,
-				       false);
+				       false, false);
 	if (status != EFI_SUCCESS) {
 		log_err("LMB Map notify failure %lu\n",
 			status & ~EFI_ERROR_MASK);