[Xen-devel] [PATCH v3 06/25] libelf-loader: introduce elf_load_image

[<stefano.stabellini@xxxxxxxxxxxxx>]

From: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>

Implement a new function, called elf_load_image, to perform the actually
copy of the elf image and clearing the padding.
The function is implemented as memcpy and memset when the library is
built as part of the tools, but it is implemented as raw_copy_to_guest and
raw_clear_guest when built as part of Xen, so that it can be safely called
with an HVM style dom0.


Changes in v3:

- switch to raw_copy_to_guest and raw_clear_guest.


Changes in v2:

- remove CONFIG_KERNEL_NO_RELOC.


Signed-off-by: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>
Signed-off-by: Ian Campbell <ian.campbell@xxxxxxxxxx>
Signed-off-by: Tim Deegan <Tim.Deegan@xxxxxxxxxx>
---
 xen/common/libelf/libelf-loader.c |   17 +++++++++++++++--
 1 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/xen/common/libelf/libelf-loader.c 
b/xen/common/libelf/libelf-loader.c
index 1ccf7d3..d2cb5b3 100644
--- a/xen/common/libelf/libelf-loader.c
+++ b/xen/common/libelf/libelf-loader.c
@@ -107,11 +107,25 @@ void elf_set_log(struct elf_binary *elf, elf_log_callback 
*log_callback,
     elf->log_caller_data = log_caller_data;
     elf->verbose = verbose;
 }
+
+static void elf_load_image(void *dst, const void *src, uint64_t filesz, 
uint64_t memsz)
+{
+    memcpy(dst, src, filesz);
+    memset(dst + filesz, 0, memsz - filesz);
+}
 #else
+#include <asm/guest_access.h>
+
 void elf_set_verbose(struct elf_binary *elf)
 {
     elf->verbose = 1;
 }
+
+static void elf_load_image(void *dst, const void *src, uint64_t filesz, 
uint64_t memsz)
+{
+    raw_copy_to_guest(dst, src, filesz);
+    raw_clear_guest(dst + filesz, memsz - filesz);
+}
 #endif
 
 /* Calculate the required additional kernel space for the elf image */
@@ -256,8 +270,7 @@ void elf_load_binary(struct elf_binary *elf)
         dest = elf_get_ptr(elf, paddr);
         elf_msg(elf, "%s: phdr %" PRIu64 " at 0x%p -> 0x%p\n",
                 __func__, i, dest, dest + filesz);
-        memcpy(dest, elf->image + offset, filesz);
-        memset(dest + filesz, 0, memsz - filesz);
+        elf_load_image(dest, elf->image + offset, filesz, memsz);
     }
 
     elf_load_bsdsyms(elf);
-- 
1.7.2.5


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel