efi_loader: macro efi_size_in_pages()

When allocating EFI memory pages the size in bytes has to be converted to
pages.

Provide a macro efi_size_in_pages() for this conversion.
Use it in the EFI subsystem and correct related comments.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Alexander Graf <agraf@suse.de>

diff --git a/cmd/bootefi.c b/cmd/bootefi.c
index eadfd934b735306f4c80ad245f931fe77b8322c9..a57b0b4fe4be2194fc9b52892d1133b914b286a0 100644 (file)
--- a/cmd/bootefi.c
+++ b/cmd/bootefi.c
@@ -149,7 +149,7 @@ static void set_load_options(struct efi_loaded_image *loaded_image_info,
  * copy_fdt() - Copy the device tree to a new location available to EFI
  *
  * The FDT is relocated into a suitable location within the EFI memory map.
- * An additional 12KB is added to the space in case the device tree needs to be
+ * Additional 12 KiB are added to the space in case the device tree needs to be
  * expanded later with fdt_open_into().
  *
  * @fdt_addr:  On entry, address of start of FDT. On exit, address of relocated
@@ -177,14 +177,12 @@ static efi_status_t copy_fdt(ulong *fdt_addrp)
        }
 
        /*
-        * Give us at least 4KB of breathing room in case the device tree needs
-        * to be expanded later. Round up to the nearest EFI page boundary.
+        * Give us at least 12 KiB of breathing room in case the device tree
+        * needs to be expanded later.
         */
        fdt = map_sysmem(*fdt_addrp, 0);
-       fdt_size = fdt_totalsize(fdt);
-       fdt_size += 4096 * 3;
-       fdt_size = ALIGN(fdt_size + EFI_PAGE_SIZE - 1, EFI_PAGE_SIZE);
-       fdt_pages = fdt_size >> EFI_PAGE_SHIFT;
+       fdt_pages = efi_size_in_pages(fdt_totalsize(fdt) + 0x3000);
+       fdt_size = fdt_pages << EFI_PAGE_SHIFT;
 
        /* Safe fdt location is at 127MB */
        new_fdt_addr = fdt_ram_start + (127 * 1024 * 1024) + fdt_size;
@@ -282,8 +280,7 @@ static void efi_carve_out_dt_rsv(void *fdt)
                if (addr == (uintptr_t)fdt)
                        continue;
 
-               pages = ALIGN(size + (addr & EFI_PAGE_MASK), EFI_PAGE_SIZE) >>
-                       EFI_PAGE_SHIFT;
+               pages = efi_size_in_pages(size + (addr & EFI_PAGE_MASK));
                addr &= ~EFI_PAGE_MASK;
                if (!efi_add_memory_map(addr, pages, EFI_RESERVED_MEMORY_TYPE,
                                        false))

diff --git a/include/efi_loader.h b/include/efi_loader.h
index f399e995060a7d05b170227bdf98b71c02ce0b47..3c90515fef178a467e42c09bffec634f0b2541d9 100644 (file)
--- a/include/efi_loader.h
+++ b/include/efi_loader.h
@@ -344,7 +344,16 @@ struct efi_simple_file_system_protocol *efi_simple_file_system(
 /* open file from device-path: */
 struct efi_file_handle *efi_file_from_path(struct efi_device_path *fp);
 
-
+/**
+ * efi_size_in_pages() - convert size in bytes to size in pages
+ *
+ * This macro returns the number of EFI memory pages required to hold 'size'
+ * bytes.
+ *
+ * @size:      size in bytes
+ * Return:     size in pages
+ */
+#define efi_size_in_pages(size) ((size + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT)
 /* Generic EFI memory allocator, call this to get memory */
 void *efi_alloc(uint64_t len, int memory_type);
 /* More specific EFI memory allocator, called by EFI payloads */

diff --git a/lib/efi_loader/efi_memory.c b/lib/efi_loader/efi_memory.c
index 307e6f77ab74763e10ec54e2dcdb14723c3a2b4a..5359118b4d7da5f2ac01c3f224995d4a92ee04fe 100644 (file)
--- a/lib/efi_loader/efi_memory.c
+++ b/lib/efi_loader/efi_memory.c
@@ -397,7 +397,7 @@ efi_status_t efi_allocate_pages(int type, int memory_type,
 void *efi_alloc(uint64_t len, int memory_type)
 {
        uint64_t ret = 0;
-       uint64_t pages = (len + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT;
+       uint64_t pages = efi_size_in_pages(len);
        efi_status_t r;
 
        r = efi_allocate_pages(EFI_ALLOCATE_ANY_PAGES, memory_type, pages,
@@ -440,8 +440,8 @@ efi_status_t efi_allocate_pool(int pool_type, efi_uintn_t size, void **buffer)
 {
        efi_status_t r;
        struct efi_pool_allocation *alloc;
-       u64 num_pages = (size + sizeof(struct efi_pool_allocation) +
-                        EFI_PAGE_MASK) >> EFI_PAGE_SHIFT;
+       u64 num_pages = efi_size_in_pages(size +
+                                         sizeof(struct efi_pool_allocation));
 
        if (!buffer)
                return EFI_INVALID_PARAMETER;