kexec_file: Allow arch-specific memory walking for kexec_add_buffer

Allow architectures to specify a different memory walking function for
kexec_add_buffer. x86 uses iomem to track reserved memory ranges, but
PowerPC uses the memblock subsystem.

Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

1 files changed, 28 insertions, 1 deletions

diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index 406c33dcae13..5e320ddaaa82 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -148,7 +148,34 @@ struct kexec_file_ops {
         kexec_verify_sig_t *verify_sig;
 #endif
 };
-#endif
+
+/**
+ * struct kexec_buf - parameters for finding a place for a buffer in memory
+ * @image:      kexec image in which memory to search.
+ * @buffer:     Contents which will be copied to the allocated memory.
+ * @bufsz:      Size of @buffer.
+ * @mem:        On return will have address of the buffer in memory.
+ * @memsz:      Size for the buffer in memory.
+ * @buf_align:  Minimum alignment needed.
+ * @buf_min:    The buffer can't be placed below this address.
+ * @buf_max:    The buffer can't be placed above this address.
+ * @top_down:   Allocate from top of memory.
+ */
+struct kexec_buf {
+        struct kimage *image;
+        char *buffer;
+        unsigned long bufsz;
+        unsigned long mem;
+        unsigned long memsz;
+        unsigned long buf_align;
+        unsigned long buf_min;
+        unsigned long buf_max;
+        bool top_down;
+};
+
+int __weak arch_kexec_walk_mem(struct kexec_buf *kbuf,
+                               int (*func)(u64, u64, void *));
+#endif /* CONFIG_KEXEC_FILE */
 
 struct kimage {
         kimage_entry_t head;