[Patch v2 1/3] take the segment adding out of locate_mem_hole functions

[Patch v2 1/3] take the segment adding out of locate_mem_hole functions

[Baoquan He]

In locate_mem_hole functions, a memory hole is located and added as
kexec_segment. But from the name of locate_mem_hole, it should only
take responsibility of searching a available memory hole to contain
data of a specified size.

So in this patch add a new field 'mem' into kexec_buf, then take that
kexec segment adding code out of locate_mem_hole_top_down and
locate_mem_hole_bottom_up. This make clear of the functionality of
locate_mem_hole just like it declars to do. And by this
locate_mem_hole_callback chould be used later if anyone want to locate
a memory hole for other use.

Meanwhile Vivek suggested opening code function __kexec_add_segment(),
that way we have to retreive ksegment pointer once and it is easy to
read. So just do it in this patch and remove __kexec_add_segment()
since no one use it anymore.

Signed-off-by: Baoquan He <bhe@redhat.com>
---
 include/linux/kexec.h |  1 +
 kernel/kexec.c        | 29 ++++++++---------------------
 2 files changed, 9 insertions(+), 21 deletions(-)

diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index 4b2a0e1..9d957b7 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -178,6 +178,7 @@ struct kexec_buf {
 	struct kimage *image;
 	char *buffer;
 	unsigned long bufsz;
+	unsigned long mem;
 	unsigned long memsz;
 	unsigned long buf_align;
 	unsigned long buf_min;
diff --git a/kernel/kexec.c b/kernel/kexec.c
index 2bee072..63bc3cd 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -2016,22 +2016,6 @@ static int __init crash_save_vmcoreinfo_init(void)
 subsys_initcall(crash_save_vmcoreinfo_init);
 
 #ifdef CONFIG_KEXEC_FILE
-static int __kexec_add_segment(struct kimage *image, char *buf,
-			       unsigned long bufsz, unsigned long mem,
-			       unsigned long memsz)
-{
-	struct kexec_segment *ksegment;
-
-	ksegment = &image->segment[image->nr_segments];
-	ksegment->kbuf = buf;
-	ksegment->bufsz = bufsz;
-	ksegment->mem = mem;
-	ksegment->memsz = memsz;
-	image->nr_segments++;
-
-	return 0;
-}
-
 static int locate_mem_hole_top_down(unsigned long start, unsigned long end,
 				    struct kexec_buf *kbuf)
 {
@@ -2064,8 +2048,7 @@ static int locate_mem_hole_top_down(unsigned long start, unsigned long end,
 	} while (1);
 
 	/* If we are here, we found a suitable memory range */
-	__kexec_add_segment(image, kbuf->buffer, kbuf->bufsz, temp_start,
-			    kbuf->memsz);
+	kbuf->mem = temp_start;
 
 	/* Success, stop navigating through remaining System RAM ranges */
 	return 1;
@@ -2099,8 +2082,7 @@ static int locate_mem_hole_bottom_up(unsigned long start, unsigned long end,
 	} while (1);
 
 	/* If we are here, we found a suitable memory range */
-	__kexec_add_segment(image, kbuf->buffer, kbuf->bufsz, temp_start,
-			    kbuf->memsz);
+	kbuf->mem = temp_start;
 
 	/* Success, stop navigating through remaining System RAM ranges */
 	return 1;
@@ -2187,7 +2169,12 @@ int kexec_add_buffer(struct kimage *image, char *buffer, unsigned long bufsz,
 	}
 
 	/* Found a suitable memory range */
-	ksegment = &image->segment[image->nr_segments - 1];
+	ksegment = &image->segment[image->nr_segments];
+	ksegment->kbuf = kbuf->buffer;
+	ksegment->bufsz = kbuf->bufsz;
+	ksegment->mem = kbuf->mem;
+	ksegment->memsz = kbuf->memsz;
+	image->nr_segments++;
 	*load_addr = ksegment->mem;
 	return 0;
 }
-- 
1.8.5.3

[Patch v2 2/3] check if crashk_res_low exists when exclude it from crash mem ranges

[Baoquan He]

Add a check if crashk_res_low exists just like GART region does. If
crashk_res_low doesn't exist, calling exclude_mem_range is unnecessary.

Meanwhile, since crashk_res_low has been initialized at definition, it's
safe just use "if (crashk_low_res.end)" to check if it's exist. And this
can make it consistent with other places of check.

Signed-off-by: Baoquan He <bhe@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
---
 arch/x86/kernel/crash.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c
index a618fcd..f5ab56d 100644
--- a/arch/x86/kernel/crash.c
+++ b/arch/x86/kernel/crash.c
@@ -237,7 +237,7 @@ static void fill_up_crash_elf_data(struct crash_elf_data *ced,
 	ced->max_nr_ranges++;
 
 	/* If crashk_low_res is not 0, another range split possible */
-	if (crashk_low_res.end != 0)
+	if (crashk_low_res.end)
 		ced->max_nr_ranges++;
 }
 
@@ -335,9 +335,11 @@ static int elf_header_exclude_ranges(struct crash_elf_data *ced,
 	if (ret)
 		return ret;
 
-	ret = exclude_mem_range(cmem, crashk_low_res.start, crashk_low_res.end);
-	if (ret)
-		return ret;
+	if (crashk_low_res.end) {
+		ret = exclude_mem_range(cmem, crashk_low_res.start, crashk_low_res.end);
+		if (ret)
+			return ret;
+	}
 
 	/* Exclude GART region */
 	if (ced->gart_end) {
-- 
1.8.5.3

[Patch v2 3/3] kexec: remove the unused function parameter

[Baoquan He]

This is a cleanup. In function parse_crashkernel_suffix, the
parameter crash_base is not used. So here remove it.

Signed-off-by: Baoquan He <bhe@redhat.com>
---
 kernel/kexec.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/kernel/kexec.c b/kernel/kexec.c
index 63bc3cd..2abf9f6 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -1759,7 +1759,6 @@ static __initdata char *suffix_tbl[] = {
  */
 static int __init parse_crashkernel_suffix(char *cmdline,
 					   unsigned long long	*crash_size,
-					   unsigned long long	*crash_base,
 					   const char *suffix)
 {
 	char *cur = cmdline;
@@ -1848,7 +1847,7 @@ static int __init __parse_crashkernel(char *cmdline,
 
 	if (suffix)
 		return parse_crashkernel_suffix(ck_cmdline, crash_size,
-				crash_base, suffix);
+				suffix);
 	/*
 	 * if the commandline contains a ':', then that's the extended
 	 * syntax -- if not, it must be the classic syntax
-- 
1.8.5.3

Re: [Patch v2 1/3] take the segment adding out of locate_mem_hole functions

[Baoquan He]

Sorry, CC this patchset to Andrew.

On 09/09/14 at 07:36pm, Baoquan He wrote:
> In locate_mem_hole functions, a memory hole is located and added as
> kexec_segment. But from the name of locate_mem_hole, it should only
> take responsibility of searching a available memory hole to contain
> data of a specified size.
> 
> So in this patch add a new field 'mem' into kexec_buf, then take that
> kexec segment adding code out of locate_mem_hole_top_down and
> locate_mem_hole_bottom_up. This make clear of the functionality of
> locate_mem_hole just like it declars to do. And by this
> locate_mem_hole_callback chould be used later if anyone want to locate
> a memory hole for other use.
> 
> Meanwhile Vivek suggested opening code function __kexec_add_segment(),
> that way we have to retreive ksegment pointer once and it is easy to
> read. So just do it in this patch and remove __kexec_add_segment()
> since no one use it anymore.
> 
> Signed-off-by: Baoquan He <bhe@redhat.com>
> ---
>  include/linux/kexec.h |  1 +
>  kernel/kexec.c        | 29 ++++++++---------------------
>  2 files changed, 9 insertions(+), 21 deletions(-)
> 
> diff --git a/include/linux/kexec.h b/include/linux/kexec.h
> index 4b2a0e1..9d957b7 100644
> --- a/include/linux/kexec.h
> +++ b/include/linux/kexec.h
> @@ -178,6 +178,7 @@ struct kexec_buf {
>  	struct kimage *image;
>  	char *buffer;
>  	unsigned long bufsz;
> +	unsigned long mem;
>  	unsigned long memsz;
>  	unsigned long buf_align;
>  	unsigned long buf_min;
> diff --git a/kernel/kexec.c b/kernel/kexec.c
> index 2bee072..63bc3cd 100644
> --- a/kernel/kexec.c
> +++ b/kernel/kexec.c
> @@ -2016,22 +2016,6 @@ static int __init crash_save_vmcoreinfo_init(void)
>  subsys_initcall(crash_save_vmcoreinfo_init);
>  
>  #ifdef CONFIG_KEXEC_FILE
> -static int __kexec_add_segment(struct kimage *image, char *buf,
> -			       unsigned long bufsz, unsigned long mem,
> -			       unsigned long memsz)
> -{
> -	struct kexec_segment *ksegment;
> -
> -	ksegment = &image->segment[image->nr_segments];
> -	ksegment->kbuf = buf;
> -	ksegment->bufsz = bufsz;
> -	ksegment->mem = mem;
> -	ksegment->memsz = memsz;
> -	image->nr_segments++;
> -
> -	return 0;
> -}
> -
>  static int locate_mem_hole_top_down(unsigned long start, unsigned long end,
>  				    struct kexec_buf *kbuf)
>  {
> @@ -2064,8 +2048,7 @@ static int locate_mem_hole_top_down(unsigned long start, unsigned long end,
>  	} while (1);
>  
>  	/* If we are here, we found a suitable memory range */
> -	__kexec_add_segment(image, kbuf->buffer, kbuf->bufsz, temp_start,
> -			    kbuf->memsz);
> +	kbuf->mem = temp_start;
>  
>  	/* Success, stop navigating through remaining System RAM ranges */
>  	return 1;
> @@ -2099,8 +2082,7 @@ static int locate_mem_hole_bottom_up(unsigned long start, unsigned long end,
>  	} while (1);
>  
>  	/* If we are here, we found a suitable memory range */
> -	__kexec_add_segment(image, kbuf->buffer, kbuf->bufsz, temp_start,
> -			    kbuf->memsz);
> +	kbuf->mem = temp_start;
>  
>  	/* Success, stop navigating through remaining System RAM ranges */
>  	return 1;
> @@ -2187,7 +2169,12 @@ int kexec_add_buffer(struct kimage *image, char *buffer, unsigned long bufsz,
>  	}
>  
>  	/* Found a suitable memory range */
> -	ksegment = &image->segment[image->nr_segments - 1];
> +	ksegment = &image->segment[image->nr_segments];
> +	ksegment->kbuf = kbuf->buffer;
> +	ksegment->bufsz = kbuf->bufsz;
> +	ksegment->mem = kbuf->mem;
> +	ksegment->memsz = kbuf->memsz;
> +	image->nr_segments++;
>  	*load_addr = ksegment->mem;
>  	return 0;
>  }
> -- 
> 1.8.5.3
> 

Re: [Patch v2 1/3] take the segment adding out of locate_mem_hole functions

[Vivek Goyal]

On Tue, Sep 09, 2014 at 07:36:18PM +0800, Baoquan He wrote:
> In locate_mem_hole functions, a memory hole is located and added as
> kexec_segment. But from the name of locate_mem_hole, it should only
> take responsibility of searching a available memory hole to contain
> data of a specified size.
> 
> So in this patch add a new field 'mem' into kexec_buf, then take that
> kexec segment adding code out of locate_mem_hole_top_down and
> locate_mem_hole_bottom_up. This make clear of the functionality of
> locate_mem_hole just like it declars to do. And by this
> locate_mem_hole_callback chould be used later if anyone want to locate
> a memory hole for other use.
> 
> Meanwhile Vivek suggested opening code function __kexec_add_segment(),
> that way we have to retreive ksegment pointer once and it is easy to
> read. So just do it in this patch and remove __kexec_add_segment()
> since no one use it anymore.
> 
> Signed-off-by: Baoquan He <bhe@redhat.com>

Bao,

These 3 patches look good to me. I am assuming you have tested these
to make sure nothing is broken.

Acked-by: Vivek Goyal <vgoyal@redhat.com>

Thanks
Vivek

> ---
>  include/linux/kexec.h |  1 +
>  kernel/kexec.c        | 29 ++++++++---------------------
>  2 files changed, 9 insertions(+), 21 deletions(-)
> 
> diff --git a/include/linux/kexec.h b/include/linux/kexec.h
> index 4b2a0e1..9d957b7 100644
> --- a/include/linux/kexec.h
> +++ b/include/linux/kexec.h
> @@ -178,6 +178,7 @@ struct kexec_buf {
>  	struct kimage *image;
>  	char *buffer;
>  	unsigned long bufsz;
> +	unsigned long mem;
>  	unsigned long memsz;
>  	unsigned long buf_align;
>  	unsigned long buf_min;
> diff --git a/kernel/kexec.c b/kernel/kexec.c
> index 2bee072..63bc3cd 100644
> --- a/kernel/kexec.c
> +++ b/kernel/kexec.c
> @@ -2016,22 +2016,6 @@ static int __init crash_save_vmcoreinfo_init(void)
>  subsys_initcall(crash_save_vmcoreinfo_init);
>  
>  #ifdef CONFIG_KEXEC_FILE
> -static int __kexec_add_segment(struct kimage *image, char *buf,
> -			       unsigned long bufsz, unsigned long mem,
> -			       unsigned long memsz)
> -{
> -	struct kexec_segment *ksegment;
> -
> -	ksegment = &image->segment[image->nr_segments];
> -	ksegment->kbuf = buf;
> -	ksegment->bufsz = bufsz;
> -	ksegment->mem = mem;
> -	ksegment->memsz = memsz;
> -	image->nr_segments++;
> -
> -	return 0;
> -}
> -
>  static int locate_mem_hole_top_down(unsigned long start, unsigned long end,
>  				    struct kexec_buf *kbuf)
>  {
> @@ -2064,8 +2048,7 @@ static int locate_mem_hole_top_down(unsigned long start, unsigned long end,
>  	} while (1);
>  
>  	/* If we are here, we found a suitable memory range */
> -	__kexec_add_segment(image, kbuf->buffer, kbuf->bufsz, temp_start,
> -			    kbuf->memsz);
> +	kbuf->mem = temp_start;
>  
>  	/* Success, stop navigating through remaining System RAM ranges */
>  	return 1;
> @@ -2099,8 +2082,7 @@ static int locate_mem_hole_bottom_up(unsigned long start, unsigned long end,
>  	} while (1);
>  
>  	/* If we are here, we found a suitable memory range */
> -	__kexec_add_segment(image, kbuf->buffer, kbuf->bufsz, temp_start,
> -			    kbuf->memsz);
> +	kbuf->mem = temp_start;
>  
>  	/* Success, stop navigating through remaining System RAM ranges */
>  	return 1;
> @@ -2187,7 +2169,12 @@ int kexec_add_buffer(struct kimage *image, char *buffer, unsigned long bufsz,
>  	}
>  
>  	/* Found a suitable memory range */
> -	ksegment = &image->segment[image->nr_segments - 1];
> +	ksegment = &image->segment[image->nr_segments];
> +	ksegment->kbuf = kbuf->buffer;
> +	ksegment->bufsz = kbuf->bufsz;
> +	ksegment->mem = kbuf->mem;
> +	ksegment->memsz = kbuf->memsz;
> +	image->nr_segments++;
>  	*load_addr = ksegment->mem;
>  	return 0;
>  }
> -- 
> 1.8.5.3