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 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 | 4 +++
kernel/kexec_file.c | 88 +++++++++++++++++++++++++++++++++++----------------
2 files changed, 64 insertions(+), 28 deletions(-)
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index 7321043aa65a..a08cd986b5a1 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -210,6 +210,10 @@ extern asmlinkage long sys_kexec_load(unsigned long entry,
struct kexec_segment __user *segments,
unsigned long flags);
extern int kernel_kexec(void);
+int kexec_locate_mem_hole(struct kimage *image, unsigned long size,
+ unsigned long align, unsigned long min_addr,
+ unsigned long max_addr, bool top_down,
+ unsigned long *addr);
extern int kexec_add_buffer(struct kimage *image, char *buffer,
unsigned long bufsz, unsigned long memsz,
unsigned long buf_align, unsigned long buf_min,
diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
index a3ca7cfe070e..3e494261d32a 100644
--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -453,6 +453,57 @@ int __weak arch_kexec_walk_mem(unsigned int image_type, unsigned long start,
return walk_system_ram_res(start, end, data, func);
}
+/**
+ * kexec_locate_mem_hole - find free memory to load segment or use in purgatory
+ * @image: kexec image being updated.
+ * @size: Memory size.
+ * @align: Minimum alignment needed.
+ * @min_addr: Minimum starting address.
+ * @max_addr: Maximum end address.
+ * @top_down Find the highest free memory region?
+ * @addr On success, will have start address of the memory region found.
+ *
+ * Return: 0 on success, negative errno on error.
+ */
+int kexec_locate_mem_hole(struct kimage *image, unsigned long size,
+ unsigned long align, unsigned long min_addr,
+ unsigned long max_addr, bool top_down,
+ unsigned long *addr)
+{
+ int ret;
+ struct kexec_buf buf;
+ unsigned long start, end;
+
+ memset(&buf, 0, sizeof(struct kexec_buf));
+ buf.image = image;
+
+ buf.memsz = size;
+ buf.buf_align = align;
+ buf.buf_min = min_addr;
+ buf.buf_max = max_addr;
+ buf.top_down = top_down;
+
+ /* Walk the RAM ranges and allocate a suitable range for the buffer */
+ 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, &buf,
+ locate_mem_hole_callback);
+ if (ret != 1) {
+ /* A suitable memory range could not be found for buffer */
+ return -EADDRNOTAVAIL;
+ }
+
+ *addr = buf.mem;
+
+ return 0;
+}
+
/*
* Helper function for placing a buffer in a kexec segment. This assumes
* that kexec_mutex is held.
@@ -464,9 +515,8 @@ 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;
+ unsigned long addr, align, size;
/* Currently adding segment this way is allowed only in file mode */
if (!image->file_mode)
@@ -487,38 +537,20 @@ int kexec_add_buffer(struct kimage *image, char *buffer, unsigned long bufsz,
return -EINVAL;
}
- memset(&buf, 0, sizeof(struct kexec_buf));
- kbuf = &buf;
- kbuf->image = image;
-
- kbuf->memsz = ALIGN(memsz, PAGE_SIZE);
- kbuf->buf_align = max(buf_align, PAGE_SIZE);
- kbuf->buf_min = buf_min;
- kbuf->buf_max = buf_max;
- kbuf->top_down = top_down;
+ size = ALIGN(memsz, PAGE_SIZE);
+ align = max(buf_align, PAGE_SIZE);
- /* Walk the RAM ranges and allocate a suitable range for the buffer */
- 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;
- }
+ ret = kexec_locate_mem_hole(image, size, align, buf_min, buf_max,
+ top_down, &addr);
+ if (ret)
+ return ret;
/* Found a suitable memory range */
ksegment = &image->segment[image->nr_segments];
ksegment->kbuf = buffer;
ksegment->bufsz = bufsz;
- ksegment->mem = kbuf->mem;
- ksegment->memsz = kbuf->memsz;
+ ksegment->mem = addr;
+ ksegment->memsz = size;
image->nr_segments++;
*load_addr = ksegment->mem;
return 0;
--
1.9.1
