Allow architectures to specify different memory walking functions for
kexec_add_buffer. Intel uses iomem to track reserved memory ranges,
but PowerPC uses the memblock subsystem.
Signed-off-by: Thiago Jung Bauermann <bauerman at linux.vnet.ibm.com>
Cc: Eric Biederman <ebiederm at xmission.com>
Cc: Dave Young <dyoung at redhat.com>
Cc: kexec at lists.infradead.org
Cc: linux-kernel at vger.kernel.org
---
include/linux/kexec.h | 3 +++
kernel/kexec_file.c | 44 ++++++++++++++++++++++++++++++++++++--------
2 files changed, 39 insertions(+), 8 deletions(-)
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index e8acb2b43dd9..7321043aa65a 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -315,6 +315,9 @@ int __weak arch_kexec_apply_relocations_add(const Elf_Ehdr *ehdr,
Elf_Shdr *sechdrs, unsigned int relsec);
int __weak arch_kexec_apply_relocations(const Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
unsigned int relsec);
+int __weak arch_kexec_walk_mem(unsigned int image_type, unsigned long start,
+ unsigned long end, bool top_down, void *data,
+ int (*func)(u64, u64, void *));
void arch_kexec_protect_crashkres(void);
void arch_kexec_unprotect_crashkres(void);
diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
index b6eec7527e9f..a3ca7cfe070e 100644
--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -428,6 +428,31 @@ static int locate_mem_hole_callback(u64 start, u64 end, void *arg)
return locate_mem_hole_bottom_up(start, end, kbuf);
}
+/**
+ * arch_kexec_walk_mem - call func(data) on free memory regions
+ * @image_type: kimage.type
+ * @start: Don't visit memory regions below this address.
+ * @end: Don't visit memory regions above this address.
+ * @top_down: Start from the highest address?
+ * @data: Argument to pass to @func.
+ * @func: Function to call for each memory region.
+ *
+ * Return: The memory walk will stop when func returns a non-zero value
+ * and that value will be returned. If all free regions are visited without
+ * func returning non-zero, then zero will be returned.
+ */
+int __weak arch_kexec_walk_mem(unsigned int image_type, unsigned long start,
+ unsigned long end, bool top_down, void *data,
+ int (*func)(u64, u64, void *))
+{
+ if (image_type == KEXEC_TYPE_CRASH)
+ return walk_iomem_res_desc(crashk_res.desc,
+ IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY,
+ start, end, data, func);
+ else
+ return walk_system_ram_res(start, end, data, func);
+}
+
/*
* Helper function for placing a buffer in a kexec segment. This assumes
* that kexec_mutex is held.
@@ -441,6 +466,7 @@ int kexec_add_buffer(struct kimage *image, char *buffer, unsigned long bufsz,
struct kexec_segment *ksegment;
struct kexec_buf buf, *kbuf;
int ret;
+ unsigned long start, end;
/* Currently adding segment this way is allowed only in file mode */
if (!image->file_mode)
@@ -472,14 +498,16 @@ int kexec_add_buffer(struct kimage *image, char *buffer, unsigned long bufsz,
kbuf->top_down = top_down;
/* Walk the RAM ranges and allocate a suitable range for the buffer */
- if (image->type == KEXEC_TYPE_CRASH)
- ret = walk_iomem_res_desc(crashk_res.desc,
- IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY,
- crashk_res.start, crashk_res.end, kbuf,
- locate_mem_hole_callback);
- else
- ret = walk_system_ram_res(0, -1, kbuf,
- locate_mem_hole_callback);
+ if (image->type == KEXEC_TYPE_CRASH) {
+ start = crashk_res.start;
+ end = crashk_res.end;
+ } else {
+ start = 0;
+ end = ULONG_MAX;
+ }
+
+ ret = arch_kexec_walk_mem(image->type, start, end, top_down, kbuf,
+ locate_mem_hole_callback);
if (ret != 1) {
/* A suitable memory range could not be found for buffer */
return -EADDRNOTAVAIL;
--
1.9.1
