[PATCH] kexec-tools ppc64: add --reuseinitrd option

[PATCH] kexec-tools ppc64: add --reuseinitrd option

[Michael Neuling]

Add a --reuseinitrd option so that initrds saved using the
retain_initrd kernel option can be reused on the kexec boot.

Signed-off-by: Michael Neuling <mikey@neuling.org>
---
Horms: applies on top of my recent cleanup patch

 kexec/arch/ppc64/fs2dt.c           |   23 +++++++++++++++++------
 kexec/arch/ppc64/kexec-elf-ppc64.c |    6 ++++++
 kexec/arch/ppc64/kexec-ppc64.c     |    1 +
 kexec/arch/ppc64/kexec-ppc64.h     |    1 +
 4 files changed, 25 insertions(+), 6 deletions(-)

Index: kexec-tools-testing/kexec/arch/ppc64/fs2dt.c
===================================================================
--- kexec-tools-testing.orig/kexec/arch/ppc64/fs2dt.c
+++ kexec-tools-testing/kexec/arch/ppc64/fs2dt.c
@@ -68,9 +68,9 @@ void reserve(unsigned long long where, u
 /* look for properties we need to reserve memory space for */
 static void checkprop(char *name, unsigned *data)
 {
-	static unsigned long long base, size;
+	static unsigned long long base, size, end;
 
-	if ((data == NULL) && (base || size))
+	if ((data == NULL) && (base || size || end))
 		die("unrecoverable error: no property data");
 	else if (!strcmp(name, "linux,rtas-base"))
 		base = *data;
@@ -79,11 +79,21 @@ static void checkprop(char *name, unsign
 	else if (!strcmp(name, "rtas-size") ||
 			!strcmp(name, "linux,tce-size"))
 		size = *data;
+	else if (reuse_initrd && !strcmp(name, "linux,initrd-start"))
+		base = *(unsigned long long *) data;
+	else if (reuse_initrd && !strcmp(name, "linux,initrd-end"))
+		end = *(unsigned long long *) data;
 
+	if (size && end)
+		die("unrecoverable error: size and end set at same time\n");
 	if (base && size) {
 		reserve(base, size);
 		base = size = 0;
 	}
+	if (base && end) {
+		reserve(base, end-base);
+		base = end = 0;
+	}
 }
 
 /*
@@ -213,10 +223,11 @@ static void putprops(char *fn, struct di
 				continue;
 
 		/* This property will be created/modified later in putnode()
-		 * So ignore it.
+		 * So ignore it, unless we are reusing the initrd.
 		 */
-		if (!strcmp(dp->d_name, "linux,initrd-start") ||
-			!strcmp(dp->d_name, "linux,initrd-end"))
+		if ((!strcmp(dp->d_name, "linux,initrd-start") ||
+		     !strcmp(dp->d_name, "linux,initrd-end")) &&
+		    !reuse_initrd)
 				continue;
 
 		if (! S_ISREG(statbuf.st_mode))
@@ -343,7 +354,7 @@ static void putnode(void)
 	putprops(dn, namelist, numlist);
 
 	/* Add initrd entries to the second kernel */
-	if (initrd_base && !strcmp(basename,"/chosen/")) {
+	if (initrd_base && !strcmp(basename,"/chosen/") && !reuse_initrd) {
 		int len = 8;
 		unsigned long long initrd_end;
 		*dt++ = 3;
Index: kexec-tools-testing/kexec/arch/ppc64/kexec-elf-ppc64.c
===================================================================
--- kexec-tools-testing.orig/kexec/arch/ppc64/kexec-elf-ppc64.c
+++ kexec-tools-testing/kexec/arch/ppc64/kexec-elf-ppc64.c
@@ -43,6 +43,7 @@
 #define BOOTLOADER_VERSION VERSION
 
 unsigned long initrd_base, initrd_size;
+unsigned char reuse_initrd = 0;
 
 int create_flatten_tree(struct kexec_info *, unsigned char **, unsigned long *,
 			char *);
@@ -95,6 +96,7 @@ int elf_ppc64_load(int argc, char **argv
 #define OPT_RAMDISK     (OPT_ARCH_MAX+1)
 #define OPT_DEVICETREEBLOB     (OPT_ARCH_MAX+2)
 #define OPT_ARGS_IGNORE		(OPT_ARCH_MAX+3)
+#define OPT_REUSE_INITRD	(OPT_ARCH_MAX+4)
 
 	static const struct option options[] = {
 		KEXEC_ARCH_OPTIONS
@@ -104,6 +106,7 @@ int elf_ppc64_load(int argc, char **argv
 		{ "initrd",             1, NULL, OPT_RAMDISK },
 		{ "devicetreeblob",     1, NULL, OPT_DEVICETREEBLOB },
 		{ "args-linux",		0, NULL, OPT_ARGS_IGNORE },
+		{ "reuseinitrd",	0, NULL, OPT_REUSE_INITRD },
 		{ 0,                    0, NULL, 0 },
 	};
 
@@ -139,6 +142,9 @@ int elf_ppc64_load(int argc, char **argv
 			break;
 		case OPT_ARGS_IGNORE:
 			break;
+		case OPT_REUSE_INITRD:
+			reuse_initrd = 1;
+			break;
 		}
 	}
 
Index: kexec-tools-testing/kexec/arch/ppc64/kexec-ppc64.c
===================================================================
--- kexec-tools-testing.orig/kexec/arch/ppc64/kexec-ppc64.c
+++ kexec-tools-testing/kexec/arch/ppc64/kexec-ppc64.c
@@ -635,6 +635,7 @@ void arch_usage(void)
 	fprintf(stderr, "     --ramdisk=<filename> Initial RAM disk.\n");
 	fprintf(stderr, "     --initrd=<filename> same as --ramdisk.\n");
 	fprintf(stderr, "     --devicetreeblob=<filename> Specify device tree blob file.\n");
+	fprintf(stderr, "     --reuseinitrd Reuse the current initrd in memory.\n");
 	fprintf(stderr, "     --elf64-core-headers Prepare core headers in ELF64 format\n");
 }
 
Index: kexec-tools-testing/kexec/arch/ppc64/kexec-ppc64.h
===================================================================
--- kexec-tools-testing.orig/kexec/arch/ppc64/kexec-ppc64.h
+++ kexec-tools-testing/kexec/arch/ppc64/kexec-ppc64.h
@@ -16,6 +16,7 @@ void reserve(unsigned long long where, u
 
 extern unsigned long initrd_base, initrd_size;
 extern int max_memory_ranges;
+extern unsigned char reuse_initrd;
 
 /* boot block version 2 as defined by the linux kernel */
 struct bootblock {

[PATCH] kexec-tools ppc64: add --reuseinitrd option

[Michael Neuling]

Add a --reuseinitrd option so that initrds saved using the
retain_initrd kernel option can be reused on the kexec boot.

Signed-off-by: Michael Neuling <mikey@neuling.org>
---
Horms: This fixes comments from Milton.  Also adds sanity checks to make
sure the old initrd was retained, and that another initrd/ramdisk is not
being specified at the same time.

fastboot is dead... love live kexec! Yay :-)

 kexec/arch/ppc64/fs2dt.c           |   36 +++++++++++++++++++++++++++---------
 kexec/arch/ppc64/kexec-elf-ppc64.c |    9 +++++++++
 kexec/arch/ppc64/kexec-ppc64.c     |    1 +
 kexec/arch/ppc64/kexec-ppc64.h     |    1 +
 4 files changed, 38 insertions(+), 9 deletions(-)

Index: kexec-tools-testing/kexec/arch/ppc64/fs2dt.c
===================================================================
--- kexec-tools-testing.orig/kexec/arch/ppc64/fs2dt.c
+++ kexec-tools-testing/kexec/arch/ppc64/fs2dt.c
@@ -66,11 +66,11 @@ void reserve(unsigned long long where, u
 }
 
 /* look for properties we need to reserve memory space for */
-static void checkprop(char *name, unsigned *data)
+static void checkprop(char *name, unsigned *data, int len)
 {
-	static unsigned long long base, size;
+	static unsigned long long base, size, end;
 
-	if ((data == NULL) && (base || size))
+	if ((data == NULL) && (base || size || end))
 		die("unrecoverable error: no property data");
 	else if (!strcmp(name, "linux,rtas-base"))
 		base = *data;
@@ -79,11 +79,24 @@ static void checkprop(char *name, unsign
 	else if (!strcmp(name, "rtas-size") ||
 			!strcmp(name, "linux,tce-size"))
 		size = *data;
+	else if (reuse_initrd && !strcmp(name, "linux,initrd-start"))
+		if (len == 8)
+			base = *(unsigned long long *) data;
+		else
+			base = *data;
+	else if (reuse_initrd && !strcmp(name, "linux,initrd-end"))
+		end = *(unsigned long long *) data;
 
+	if (size && end)
+		die("unrecoverable error: size and end set at same time\n");
 	if (base && size) {
 		reserve(base, size);
 		base = size = 0;
 	}
+	if (base && end) {
+		reserve(base, end-base);
+		base = end = 0;
+	}
 }
 
 /*
@@ -213,10 +226,11 @@ static void putprops(char *fn, struct di
 				continue;
 
 		/* This property will be created/modified later in putnode()
-		 * So ignore it.
+		 * So ignore it, unless we are reusing the initrd.
 		 */
-		if (!strcmp(dp->d_name, "linux,initrd-start") ||
-			!strcmp(dp->d_name, "linux,initrd-end"))
+		if ((!strcmp(dp->d_name, "linux,initrd-start") ||
+		     !strcmp(dp->d_name, "linux,initrd-end")) &&
+		    !reuse_initrd)
 				continue;
 
 		if (! S_ISREG(statbuf.st_mode))
@@ -241,7 +255,7 @@ static void putprops(char *fn, struct di
 			die("unrecoverable error: could not read \"%s\": %s\n",
 			    pathname, strerror(errno));
 
-		checkprop(fn, dt);
+		checkprop(fn, dt, len);
 
 		/* Get the cmdline from the device-tree and modify it */
 		if (!strcmp(dp->d_name, "bootargs")) {
@@ -249,6 +263,10 @@ static void putprops(char *fn, struct di
 			char temp_cmdline[COMMAND_LINE_SIZE] = { "" };
 			char *param = NULL;
 			cmd_len = strlen(local_cmdline);
+			if (reuse_initrd &&
+			    (strstr((char *)dt, "retain_initrd") == NULL))
+				die("unrecoverable error: current boot didn't "
+				    "retain the initrd for reuse.\n");
 			if (cmd_len != 0) {
 				param = strstr(local_cmdline, "crashkernel=");
 				if (param)
@@ -282,7 +300,7 @@ static void putprops(char *fn, struct di
 	}
 
 	fn[0] = '\0';
-	checkprop(pathname, NULL);
+	checkprop(pathname, NULL, 0);
 }
 
 /*
@@ -343,7 +361,7 @@ static void putnode(void)
 	putprops(dn, namelist, numlist);
 
 	/* Add initrd entries to the second kernel */
-	if (initrd_base && !strcmp(basename,"/chosen/")) {
+	if (initrd_base && !strcmp(basename,"/chosen/") && !reuse_initrd) {
 		int len = 8;
 		unsigned long long initrd_end;
 		*dt++ = 3;
Index: kexec-tools-testing/kexec/arch/ppc64/kexec-elf-ppc64.c
===================================================================
--- kexec-tools-testing.orig/kexec/arch/ppc64/kexec-elf-ppc64.c
+++ kexec-tools-testing/kexec/arch/ppc64/kexec-elf-ppc64.c
@@ -43,6 +43,7 @@
 #define BOOTLOADER_VERSION VERSION
 
 unsigned long initrd_base, initrd_size;
+unsigned char reuse_initrd = 0;
 
 int create_flatten_tree(struct kexec_info *, unsigned char **, unsigned long *,
 			char *);
@@ -95,6 +96,7 @@ int elf_ppc64_load(int argc, char **argv
 #define OPT_RAMDISK     (OPT_ARCH_MAX+1)
 #define OPT_DEVICETREEBLOB     (OPT_ARCH_MAX+2)
 #define OPT_ARGS_IGNORE		(OPT_ARCH_MAX+3)
+#define OPT_REUSE_INITRD	(OPT_ARCH_MAX+4)
 
 	static const struct option options[] = {
 		KEXEC_ARCH_OPTIONS
@@ -104,6 +106,7 @@ int elf_ppc64_load(int argc, char **argv
 		{ "initrd",             1, NULL, OPT_RAMDISK },
 		{ "devicetreeblob",     1, NULL, OPT_DEVICETREEBLOB },
 		{ "args-linux",		0, NULL, OPT_ARGS_IGNORE },
+		{ "reuseinitrd",	0, NULL, OPT_REUSE_INITRD },
 		{ 0,                    0, NULL, 0 },
 	};
 
@@ -139,6 +142,9 @@ int elf_ppc64_load(int argc, char **argv
 			break;
 		case OPT_ARGS_IGNORE:
 			break;
+		case OPT_REUSE_INITRD:
+			reuse_initrd = 1;
+			break;
 		}
 	}
 
@@ -148,6 +154,9 @@ int elf_ppc64_load(int argc, char **argv
 	else
 		fprintf(stdout, "Warning: append= option is not passed. Using the first kernel root partition\n");
 
+	if (ramdisk && reuse_initrd)
+		die("Can't specify --ramdisk or --initrd with --reuseinitrd\n");
+
 	setup_memory_ranges(info->kexec_flags);
 
 	/* Need to append some command line parameters internally in case of
Index: kexec-tools-testing/kexec/arch/ppc64/kexec-ppc64.c
===================================================================
--- kexec-tools-testing.orig/kexec/arch/ppc64/kexec-ppc64.c
+++ kexec-tools-testing/kexec/arch/ppc64/kexec-ppc64.c
@@ -635,6 +635,7 @@ void arch_usage(void)
 	fprintf(stderr, "     --ramdisk=<filename> Initial RAM disk.\n");
 	fprintf(stderr, "     --initrd=<filename> same as --ramdisk.\n");
 	fprintf(stderr, "     --devicetreeblob=<filename> Specify device tree blob file.\n");
+	fprintf(stderr, "     --reuseinitrd Reuse the current initrd in memory.\n");
 	fprintf(stderr, "     --elf64-core-headers Prepare core headers in ELF64 format\n");
 }
 
Index: kexec-tools-testing/kexec/arch/ppc64/kexec-ppc64.h
===================================================================
--- kexec-tools-testing.orig/kexec/arch/ppc64/kexec-ppc64.h
+++ kexec-tools-testing/kexec/arch/ppc64/kexec-ppc64.h
@@ -16,6 +16,7 @@ void reserve(unsigned long long where, u
 
 extern unsigned long initrd_base, initrd_size;
 extern int max_memory_ranges;
+extern unsigned char reuse_initrd;
 
 /* boot block version 2 as defined by the linux kernel */
 struct bootblock {

Re: [PATCH] kexec-tools ppc64: add --reuseinitrd option

[Milton Miller]

On Apr 18, 2007, at 11:29 PM, Michael Neuling wrote:

> Add a --reuseinitrd option so that initrds saved using the
> retain_initrd kernel option can be reused on the kexec boot.
>
> Signed-off-by: Michael Neuling <mikey@neuling.org>
> ---
> Horms: This fixes comments from Milton.  Also adds sanity checks to 
> make
> sure the old initrd was retained, and that another initrd/ramdisk is 
> not
> being specified at the same time.
>
> fastboot is dead... love live kexec! Yay :-)
>

> -		checkprop(fn, dt);
> +		checkprop(fn, dt, len);
>
>  		/* Get the cmdline from the device-tree and modify it */
>  		if (!strcmp(dp->d_name, "bootargs")) {
> @@ -249,6 +263,10 @@ static void putprops(char *fn, struct di
>  			char temp_cmdline[COMMAND_LINE_SIZE] = { "" };
>  			char *param = NULL;
>  			cmd_len = strlen(local_cmdline);
> +			if (reuse_initrd &&
> +			    (strstr((char *)dt, "retain_initrd") == NULL))
> +				die("unrecoverable error: current boot didn't "
> +				    "retain the initrd for reuse.\n");

Although this seems efficent to look at what was in the device tree,
I'd prefer we actually looked at /proc/cmdline when we parse the
arg, so that we are sure to find what the kernel is actually
using for the command line.

Besides it will be eaiser for other archs to copy the check.

>  			if (cmd_len != 0) {
>  				param = strstr(local_cmdline, "crashkernel=");
>  				if (param)
> @@ -282,7 +300,7 @@ static void putprops(char *fn, struct di
>  	}
>
>  	fn[0] = '\0';
> -	checkprop(pathname, NULL);
> +	checkprop(pathname, NULL, 0);
>  }
>
>  /*
> @@ -343,7 +361,7 @@ static void putnode(void)
>  	putprops(dn, namelist, numlist);
>
>  	/* Add initrd entries to the second kernel */
> -	if (initrd_base && !strcmp(basename,"/chosen/")) {
> +	if (initrd_base && !strcmp(basename,"/chosen/") && !reuse_initrd) {

How does initrd_base get set if you disallow --initrd= ?

>
> @@ -148,6 +154,9 @@ int elf_ppc64_load(int argc, char **argv
>  	else
>  		fprintf(stdout, "Warning: append= option is not passed. Using the 
> first kernel root partition\n");
>
> +	if (ramdisk && reuse_initrd)
> +		die("Can't specify --ramdisk or --initrd with --reuseinitrd\n");
> +

This check is generic, not elf specific, so it should be where
we pass the args.  Hmm, maybe this is that place and it just
wants abstracting, I don't have the tree in front of me.

>  	setup_memory_ranges(info->kexec_flags);
>
>  	/* Need to append some command line parameters internally in case of
>

milton

Re: [PATCH] kexec-tools ppc64: add --reuseinitrd option

[Michael Neuling]

In message <46b0d1603ea2ab82b37daaa1888e8793@bga.com> you wrote:
> 
> On Apr 18, 2007, at 11:29 PM, Michael Neuling wrote:
> 
> > Add a --reuseinitrd option so that initrds saved using the
> > retain_initrd kernel option can be reused on the kexec boot.
> >
> > Signed-off-by: Michael Neuling <mikey@neuling.org>
> > ---
> > Horms: This fixes comments from Milton.  Also adds sanity checks to 
> > make
> > sure the old initrd was retained, and that another initrd/ramdisk is 
> > not
> > being specified at the same time.
> >
> > fastboot is dead... love live kexec! Yay :-)
> >
> 
> > -		checkprop(fn, dt);
> > +		checkprop(fn, dt, len);
> >
> >  		/* Get the cmdline from the device-tree and modify it */
> >  		if (!strcmp(dp->d_name, "bootargs")) {
> > @@ -249,6 +263,10 @@ static void putprops(char *fn, struct di
> >  			char temp_cmdline[COMMAND_LINE_SIZE] = { "" };
> >  			char *param = NULL;
> >  			cmd_len = strlen(local_cmdline);
> > +			if (reuse_initrd &&
> > +			    (strstr((char *)dt, "retain_initrd") == NULL))
> > +				die("unrecoverable error: current boot didn't "
> > +				    "retain the initrd for reuse.\n");
> 
> Although this seems efficent to look at what was in the device tree,
> I'd prefer we actually looked at /proc/cmdline when we parse the
> arg, so that we are sure to find what the kernel is actually
> using for the command line.
> 
> Besides it will be eaiser for other archs to copy the check.

Looks like we should make it a generic option.  If we do, this should
probably be two patches.  One to introduce the option, and one for the
ppc64 specific parts.

Do any of the other architectures allow you to see where the initrd is
located for the current boot from user space?  If not, the option will
need to take two parameters saying where the retained initrd is.  This
will make the option less generic (if not, we'll need to change the
other archs to export these values to user space).

> >  	/* Add initrd entries to the second kernel */
> > -	if (initrd_base && !strcmp(basename,"/chosen/")) {
> > +	if (initrd_base && !strcmp(basename,"/chosen/") && !reuse_initrd) {
> 
> How does initrd_base get set if you disallow --initrd= ?

Oops, that's left over crud.  Thanks.

When using this option, the initrd entries get imported from the first
kernel, rather than being generated here.

> 
> >
> > @@ -148,6 +154,9 @@ int elf_ppc64_load(int argc, char **argv
> >  	else
> >  		fprintf(stdout, "Warning: append= option is not passed. Using t
he 
> > first kernel root partition\n");
> >
> > +	if (ramdisk && reuse_initrd)
> > +		die("Can't specify --ramdisk or --initrd with --reuseinitrd\n")
;
> > +
> 
> This check is generic, not elf specific, so it should be where
> we pass the args.  Hmm, maybe this is that place and it just
> wants abstracting, I don't have the tree in front of me.

I put it here so the error's caught independent of the arg parsing
order.  Otherwise, we'd need to duplicate the check.

I think it's the right place, unless we move it to an arch generic
option. 

Mikey

Re: [PATCH] kexec-tools ppc64: add --reuseinitrd option

[Milton Miller]

On Apr 20, 2007, at 2:23 AM, Michael Neuling wrote:
> In message <46b0d1603ea2ab82b37daaa1888e8793@bga.com> you wrote:
>> On Apr 18, 2007, at 11:29 PM, Michael Neuling wrote:
>>> Add a --reuseinitrd option so that initrds saved using the
>>> retain_initrd kernel option can be reused on the kexec boot.
>>
>> Although this seems efficent to look at what was in the device tree,
>> I'd prefer we actually looked at /proc/cmdline when we parse the
>> arg, so that we are sure to find what the kernel is actually
>> using for the command line.
>>
>> Besides it will be eaiser for other archs to copy the check.
>
> Looks like we should make it a generic option.  If we do, this should
> probably be two patches.  One to introduce the option, and one for the
> ppc64 specific parts.
>
> Do any of the other architectures allow you to see where the initrd is
> located for the current boot from user space?  If not, the option will
> need to take two parameters saying where the retained initrd is.  This
> will make the option less generic (if not, we'll need to change the
> other archs to export these values to user space).

Since we just added the option to the kernel, I'm guessing not.
Most of them use /proc/iomem with resources for finding system ram,
the kernel text and crash kernel region, so they should probably
add a resource there when the initrd is retained.  We (powerpc) export
our bootloader data aka device tree instead, and make kexec-tools
parse it.  I don't know how sparc passes an initrd to the kernel.

>>> @@ -148,6 +154,9 @@ int elf_ppc64_load(int argc, char **argv
>>>  	else
>>>  		fprintf(stdout, "Warning: append= option is not passed. Using t
> he
>>> first kernel root partition\n");
>>>
>>> +	if (ramdisk && reuse_initrd)
>>> +		die("Can't specify --ramdisk or --initrd with --reuseinitrd\n")
> ;
>>> +
>>
>> This check is generic, not elf specific, so it should be where
>> we pass the args.  Hmm, maybe this is that place and it just
>> wants abstracting, I don't have the tree in front of me.
>
> I put it here so the error's caught independent of the arg parsing
> order.  Otherwise, we'd need to duplicate the check.
>
> I think it's the right place, unless we move it to an arch generic
> option.

I didn't mean as we parse the option, but is there not something
that gets called after we parse all the options?   Maybe that is
just the load function.   I was just thinking it should be in a
sanity_check_args() function that looks for exclusive options like
these rather than in "load a kernel like elf file", although that
is the only current option for ppc64, so it might be ok here.

milton

[PATCH 1/2] kexec: Added generic --reuseinitrd option

[Michael Neuling]

Adds a generic --reuseinitrd option and performs some sanity checks on
it.  Can be used with the retain_initrd kernel option.

---
This series attempts to address some of Milton's concerns.

 kexec/kexec.c |   33 +++++++++++++++++++++++++++++++++
 kexec/kexec.h |    2 ++
 2 files changed, 35 insertions(+)

Index: kexec-tools-testing/kexec/kexec.c
===================================================================
--- kexec-tools-testing.orig/kexec/kexec.c
+++ kexec-tools-testing/kexec/kexec.c
@@ -748,6 +748,7 @@ void usage(void)
 	       "                      load code into.\n"
 	       "     --mem-max=<addr> Specify the highest memory address to\n"
 	       "                      load code into.\n"
+	       "     --reuseinird     Reuse initrd from first boot.\n"
 	       "\n"
 	       "Supported kernel file types and options: \n");
 	for (i = 0; i < file_types; i++) {
@@ -772,6 +773,29 @@ static int kexec_loaded(void)
 	return ret;
 }
 
+/* check we retained the initrd */
+void check_reuse_initrd(void)
+{
+	FILE * fp;
+	char * line = NULL;
+	size_t len = 0;
+	ssize_t read;
+
+	fp = fopen("/proc/cmdline", "r");
+	if (fp == NULL)
+		die("unable to open /proc/cmdline\n");
+	read = getline(&line, &len, fp);
+	if (strstr(line, "retain_initrd") == NULL)
+		die("unrecoverable error: current boot didn't "
+		    "retain the initrd for reuse.\n");
+}
+
+/* Arch hook for reuse_initrd */
+void __attribute__((weak)) arch_reuse_initrd(void)
+{
+	die("--reuseinitrd not implemented on this architecture\n");
+}
+
 int main(int argc, char *argv[])
 {
 	int do_load = 1;
@@ -780,6 +804,7 @@ int main(int argc, char *argv[])
 	int do_sync = 1;
 	int do_ifdown = 0;
 	int do_unload = 0;
+	int do_reuse_initrd = 0;
 	unsigned long kexec_flags = 0;
 	char *type = 0;
 	char *endptr;
@@ -860,6 +885,9 @@ int main(int argc, char *argv[])
 				return 1;
 			}
 			break;
+		case OPT_REUSE_INITRD:
+			do_reuse_initrd = 1;
+			break;
 		default:
 			break;
 		}
@@ -890,6 +918,11 @@ int main(int argc, char *argv[])
 		}
 	}
 
+	if (do_reuse_initrd){
+		check_reuse_initrd();
+		arch_reuse_initrd();
+	}
+
 	if (do_unload) {
 		result = k_unload(kexec_flags);
 	}
Index: kexec-tools-testing/kexec/kexec.h
===================================================================
--- kexec-tools-testing.orig/kexec/kexec.h
+++ kexec-tools-testing/kexec/kexec.h
@@ -163,6 +163,7 @@ extern int file_types;
 #define OPT_MEM_MIN             256
 #define OPT_MEM_MAX             257
 #define OPT_MAX			258
+#define OPT_REUSE_INITRD	259
 #define KEXEC_OPTIONS \
 	{ "help",		0, 0, OPT_HELP }, \
 	{ "version",		0, 0, OPT_VERSION }, \
@@ -175,6 +176,7 @@ extern int file_types;
 	{ "load-panic",         0, 0, OPT_PANIC }, \
 	{ "mem-min",		1, 0, OPT_MEM_MIN }, \
 	{ "mem-max",		1, 0, OPT_MEM_MAX }, \
+	{ "reuseinitrd",	0, 0, OPT_REUSE_INITRD }, \
 
 #define KEXEC_OPT_STR "hvdfxluet:p"
 

[PATCH 2/2] kexec ppc64: Add arch specific --reuseinitrd hooks

[Michael Neuling]

Adds ppc64 specific hooks for the --reuseinitrd option.
--
 kexec/arch/ppc64/fs2dt.c           |   30 ++++++++++++++++++++++--------
 kexec/arch/ppc64/kexec-elf-ppc64.c |   13 ++++++++++++-
 kexec/arch/ppc64/kexec-ppc64.h     |    1 +
 3 files changed, 35 insertions(+), 9 deletions(-)

Index: kexec-tools-testing/kexec/arch/ppc64/fs2dt.c
===================================================================
--- kexec-tools-testing.orig/kexec/arch/ppc64/fs2dt.c
+++ kexec-tools-testing/kexec/arch/ppc64/fs2dt.c
@@ -66,11 +66,11 @@ void reserve(unsigned long long where, u
 }
 
 /* look for properties we need to reserve memory space for */
-static void checkprop(char *name, unsigned *data)
+static void checkprop(char *name, unsigned *data, int len)
 {
-	static unsigned long long base, size;
+	static unsigned long long base, size, end;
 
-	if ((data == NULL) && (base || size))
+	if ((data == NULL) && (base || size || end))
 		die("unrecoverable error: no property data");
 	else if (!strcmp(name, "linux,rtas-base"))
 		base = *data;
@@ -79,11 +79,24 @@ static void checkprop(char *name, unsign
 	else if (!strcmp(name, "rtas-size") ||
 			!strcmp(name, "linux,tce-size"))
 		size = *data;
+	else if (reuse_initrd && !strcmp(name, "linux,initrd-start"))
+		if (len == 8)
+			base = *(unsigned long long *) data;
+		else
+			base = *data;
+	else if (reuse_initrd && !strcmp(name, "linux,initrd-end"))
+		end = *(unsigned long long *) data;
 
+	if (size && end)
+		die("unrecoverable error: size and end set at same time\n");
 	if (base && size) {
 		reserve(base, size);
 		base = size = 0;
 	}
+	if (base && end) {
+		reserve(base, end-base);
+		base = end = 0;
+	}
 }
 
 /*
@@ -213,10 +226,11 @@ static void putprops(char *fn, struct di
 				continue;
 
 		/* This property will be created/modified later in putnode()
-		 * So ignore it.
+		 * So ignore it, unless we are reusing the initrd.
 		 */
-		if (!strcmp(dp->d_name, "linux,initrd-start") ||
-			!strcmp(dp->d_name, "linux,initrd-end"))
+		if ((!strcmp(dp->d_name, "linux,initrd-start") ||
+		     !strcmp(dp->d_name, "linux,initrd-end")) &&
+		    !reuse_initrd)
 				continue;
 
 		if (! S_ISREG(statbuf.st_mode))
@@ -241,7 +255,7 @@ static void putprops(char *fn, struct di
 			die("unrecoverable error: could not read \"%s\": %s\n",
 			    pathname, strerror(errno));
 
-		checkprop(fn, dt);
+		checkprop(fn, dt, len);
 
 		/* Get the cmdline from the device-tree and modify it */
 		if (!strcmp(dp->d_name, "bootargs")) {
@@ -282,7 +296,7 @@ static void putprops(char *fn, struct di
 	}
 
 	fn[0] = '\0';
-	checkprop(pathname, NULL);
+	checkprop(pathname, NULL, 0);
 }
 
 /*
Index: kexec-tools-testing/kexec/arch/ppc64/kexec-elf-ppc64.c
===================================================================
--- kexec-tools-testing.orig/kexec/arch/ppc64/kexec-elf-ppc64.c
+++ kexec-tools-testing/kexec/arch/ppc64/kexec-elf-ppc64.c
@@ -43,6 +43,8 @@
 #define BOOTLOADER_VERSION VERSION
 
 unsigned long initrd_base, initrd_size;
+unsigned char reuse_initrd = 0;
+const char *ramdisk;
 
 int create_flatten_tree(struct kexec_info *, unsigned char **, unsigned long *,
 			char *);
@@ -69,12 +71,17 @@ int elf_ppc64_probe(const char *buf, off
 	return result;
 }
 
+void arch_reuse_initrd(void)
+{
+	reuse_initrd = 1;
+}
+
 int elf_ppc64_load(int argc, char **argv, const char *buf, off_t len,
 			struct kexec_info *info)
 {
 	struct mem_ehdr ehdr;
 	char *cmdline, *modified_cmdline;
-	const char *ramdisk, *devicetreeblob;
+	const char *devicetreeblob;
 	int cmdline_len, modified_cmdline_len;
 	unsigned long long max_addr, hole_addr;
 	unsigned char *seg_buf = NULL;
@@ -148,6 +155,10 @@ int elf_ppc64_load(int argc, char **argv
 	else
 		fprintf(stdout, "Warning: append= option is not passed. Using the first kernel root partition\n");
 
+	if (ramdisk && reuse_initrd)
+		die("Can't specify --ramdisk or --initrd with "
+		    "--reuseinitrd\n");
+
 	setup_memory_ranges(info->kexec_flags);
 
 	/* Need to append some command line parameters internally in case of
Index: kexec-tools-testing/kexec/arch/ppc64/kexec-ppc64.h
===================================================================
--- kexec-tools-testing.orig/kexec/arch/ppc64/kexec-ppc64.h
+++ kexec-tools-testing/kexec/arch/ppc64/kexec-ppc64.h
@@ -16,6 +16,7 @@ void reserve(unsigned long long where, u
 
 extern unsigned long initrd_base, initrd_size;
 extern int max_memory_ranges;
+extern unsigned char reuse_initrd;
 
 /* boot block version 2 as defined by the linux kernel */
 struct bootblock {