kexec_file: kexec_walk_memblock() only walks a dedicated region at kdump

In kdump case, there exists only one dedicated memblock region as usable
memory (crashk_res). With this patch, kexec_walk_memblock() runs a given
callback function on this region.

Cosmetic change: 0 to MEMBLOCK_NONE at for_each_free_mem_range*()

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

1 files changed, 6 insertions, 3 deletions

diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
index d03195a8cb6e..f1d0e00a3971 100644
--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -515,8 +515,11 @@ static int kexec_walk_memblock(struct kexec_buf *kbuf,
         phys_addr_t mstart, mend;
         struct resource res = { };
 
+        if (kbuf->image->type == KEXEC_TYPE_CRASH)
+                return func(&crashk_res, kbuf);
+
         if (kbuf->top_down) {
-                for_each_free_mem_range_reverse(i, NUMA_NO_NODE, 0,
+                for_each_free_mem_range_reverse(i, NUMA_NO_NODE, MEMBLOCK_NONE,
                                                 &mstart, &mend, NULL) {
                         /*
                          * In memblock, end points to the first byte after the
@@ -530,8 +533,8 @@ static int kexec_walk_memblock(struct kexec_buf *kbuf,
                                 break;
                 }
         } else {
-                for_each_free_mem_range(i, NUMA_NO_NODE, 0, &mstart, &mend,
-                                        NULL) {
+                for_each_free_mem_range(i, NUMA_NO_NODE, MEMBLOCK_NONE,
+                                        &mstart, &mend, NULL) {
                         /*
                          * In memblock, end points to the first byte after the
                          * range while in kexec, end points to the last byte