kexec_file: Factor out kexec_locate_mem_hole from kexec_add_buffer.

kexec_locate_mem_hole will be used by the PowerPC kexec_file_load
implementation to find free memory for the purgatory stack.

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

diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index 437ef1b474284ea90cd9f161dc0514201a832eec..a33f63351f86f0ce530570a79ce0c4841e03e388 100644 (file)
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -176,6 +176,7 @@ struct kexec_buf {
 int __weak arch_kexec_walk_mem(struct kexec_buf *kbuf,
                               int (*func)(u64, u64, void *));
 extern int kexec_add_buffer(struct kexec_buf *kbuf);
+int kexec_locate_mem_hole(struct kexec_buf *kbuf);
 #endif /* CONFIG_KEXEC_FILE */
 
 struct kimage {

diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
index efd2c094af7e2eda3a16be3a6dfe57dde805236c..0c2df7f737925b6d0bd5bf624ceb12e8a6d53d86 100644 (file)
--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -449,6 +449,23 @@ int __weak arch_kexec_walk_mem(struct kexec_buf *kbuf,
                return walk_system_ram_res(0, ULONG_MAX, kbuf, func);
 }
 
+/**
+ * kexec_locate_mem_hole - find free memory for the purgatory or the next kernel
+ * @kbuf:      Parameters for the memory search.
+ *
+ * On success, kbuf->mem will have the start address of the memory region found.
+ *
+ * Return: 0 on success, negative errno on error.
+ */
+int kexec_locate_mem_hole(struct kexec_buf *kbuf)
+{
+       int ret;
+
+       ret = arch_kexec_walk_mem(kbuf, locate_mem_hole_callback);
+
+       return ret == 1 ? 0 : -EADDRNOTAVAIL;
+}
+
 /**
  * kexec_add_buffer - place a buffer in a kexec segment
  * @kbuf:      Buffer contents and memory parameters.
@@ -489,11 +506,9 @@ int kexec_add_buffer(struct kexec_buf *kbuf)
        kbuf->buf_align = max(kbuf->buf_align, PAGE_SIZE);
 
        /* Walk the RAM ranges and allocate a suitable range for the buffer */
-       ret = arch_kexec_walk_mem(kbuf, locate_mem_hole_callback);
-       if (ret != 1) {
-               /* A suitable memory range could not be found for buffer */
-               return -EADDRNOTAVAIL;
-       }
+       ret = kexec_locate_mem_hole(kbuf);
+       if (ret)
+               return ret;
 
        /* Found a suitable memory range */
        ksegment = &kbuf->image->segment[kbuf->image->nr_segments];