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 | 66 ++++++++++++++++++++++++++++++++++++++------------- 2 files changed, 53 insertions(+), 17 deletions(-) diff --git a/include/linux/kexec.h b/include/linux/kexec.h index 3d91bcfc180d..4ca6f5f95d66 100644 --- a/include/linux/kexec.h +++ b/include/linux/kexec.h @@ -227,6 +227,10 @@ 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 b1f1f6402518..85a515511925 100644 --- a/kernel/kexec_file.c +++ b/kernel/kexec_file.c @@ -449,6 +449,46 @@ 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 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; + + 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; + + ret = arch_kexec_walk_mem(&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. @@ -460,8 +500,8 @@ 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 addr, align, size; /* Currently adding segment this way is allowed only in file mode */ if (!image->file_mode) @@ -482,29 +522,21 @@ 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 */ - 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(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