[PATCH V3] purgatory: fix up declarations

[PATCH V3] purgatory: fix up declarations

[Nicholas Mc Guire]

Add the missing declarations of basic purgatory functions and variables
to allow a clean build.

Fixes: commit 8fc5b4d4121c ("purgatory: core purgatory functionality")
Link: http://lkml.org/lkml/2017/1/4/25
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
---

V2: after kbuild test robot <lkp@intel.com> reported a build failure
    removed incorrect declaration of copy_backup_region which is static
    anyway.

V3: move it all into purgatory.h as fixing up the declarations in the .c
    file as suggested by Dave Young <dyoung@redhat.com>, fixes the sparse
    warnings but then triggers a batch of checkpatch warnings. So the only
    clear solution it seems is to move it to a dedicated .h file.

sparse complained about:
  CHECK   arch/x86/purgatory/purgatory.c
arch/x86/purgatory/purgatory.c:21:15: warning: symbol 'backup_dest' was not declared. Should it be static?
arch/x86/purgatory/purgatory.c:22:15: warning: symbol 'backup_src' was not declared. Should it be static?
arch/x86/purgatory/purgatory.c:23:15: warning: symbol 'backup_sz' was not declared. Should it be static?
arch/x86/purgatory/purgatory.c:25:4: warning: symbol 'sha256_digest' was not declared. Should it be static?
arch/x86/purgatory/purgatory.c:27:19: warning: symbol 'sha_regions' was not declared. Should it be static?
arch/x86/purgatory/purgatory.c:42:5: warning: symbol 'verify_sha256_digest' was not declared. Should it be static?
arch/x86/purgatory/purgatory.c:61:6: warning: symbol 'purgatory' was not declared. Should it be static?
  CC      arch/x86/purgatory/purgatory.o

Numerous sparse messages regarding functions not being declared, these
functions are resolved via kexec_purgatory_get_set_symbol() and not
directly called anywhere. To resolve the sparse issues appropriate
declarations were added in a dedicated purgatory.h file.

Patch was compile tested with: x86_64_defconfig (implies CONFIG_KEXEC=y)

Patch is against 4.10-rc2 (localversion-next is next-20170106)

 arch/x86/purgatory/purgatory.c |  6 +-----
 arch/x86/purgatory/purgatory.h | 24 ++++++++++++++++++++++++
 2 files changed, 25 insertions(+), 5 deletions(-)
 create mode 100644 arch/x86/purgatory/purgatory.h

diff --git a/arch/x86/purgatory/purgatory.c b/arch/x86/purgatory/purgatory.c
index 25e068b..9420fe5 100644
--- a/arch/x86/purgatory/purgatory.c
+++ b/arch/x86/purgatory/purgatory.c
@@ -12,11 +12,7 @@
 
 #include "sha256.h"
 #include "../boot/string.h"
-
-struct sha_region {
-	unsigned long start;
-	unsigned long len;
-};
+#include "purgatory.h"
 
 unsigned long backup_dest = 0;
 unsigned long backup_src = 0;
diff --git a/arch/x86/purgatory/purgatory.h b/arch/x86/purgatory/purgatory.h
new file mode 100644
index 0000000..2754e83
--- /dev/null
+++ b/arch/x86/purgatory/purgatory.h
@@ -0,0 +1,24 @@
+#ifndef BOOT_PURGATORY_H
+#define BOOT_PURGATORY_H
+
+/* This is really just to make sparse happy.
+ * Declaring it all static as sparse suggests is not an option as,
+ * the symbol information is needed. see kexec_purgatory_get_set_symbol()
+ * Technically these prototype and extern declarations are unnecessary
+ */
+void purgatory(void);
+int verify_sha256_digest(void);
+
+extern unsigned long backup_dest;
+extern unsigned long backup_src;
+extern unsigned long backup_sz;
+
+struct sha_region {
+	unsigned long start;
+	unsigned long len;
+};
+
+extern u8 sha256_digest[];
+extern struct sha_region sha_regions[];
+
+#endif
-- 
2.1.4

Re: [PATCH V3] purgatory: fix up declarations

[Dave Young]

On 01/07/17 at 05:22pm, Nicholas Mc Guire wrote:
> Add the missing declarations of basic purgatory functions and variables
> to allow a clean build.
> 
> Fixes: commit 8fc5b4d4121c ("purgatory: core purgatory functionality")
> Link: http://lkml.org/lkml/2017/1/4/25
> Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
> ---
> 
> V2: after kbuild test robot <lkp@intel.com> reported a build failure
>     removed incorrect declaration of copy_backup_region which is static
>     anyway.
> 
> V3: move it all into purgatory.h as fixing up the declarations in the .c
>     file as suggested by Dave Young <dyoung@redhat.com>, fixes the sparse
>     warnings but then triggers a batch of checkpatch warnings. So the only
>     clear solution it seems is to move it to a dedicated .h file.
> 
> sparse complained about:
>   CHECK   arch/x86/purgatory/purgatory.c
> arch/x86/purgatory/purgatory.c:21:15: warning: symbol 'backup_dest' was not declared. Should it be static?
> arch/x86/purgatory/purgatory.c:22:15: warning: symbol 'backup_src' was not declared. Should it be static?
> arch/x86/purgatory/purgatory.c:23:15: warning: symbol 'backup_sz' was not declared. Should it be static?
> arch/x86/purgatory/purgatory.c:25:4: warning: symbol 'sha256_digest' was not declared. Should it be static?
> arch/x86/purgatory/purgatory.c:27:19: warning: symbol 'sha_regions' was not declared. Should it be static?
> arch/x86/purgatory/purgatory.c:42:5: warning: symbol 'verify_sha256_digest' was not declared. Should it be static?
> arch/x86/purgatory/purgatory.c:61:6: warning: symbol 'purgatory' was not declared. Should it be static?
>   CC      arch/x86/purgatory/purgatory.o
> 
> Numerous sparse messages regarding functions not being declared, these
> functions are resolved via kexec_purgatory_get_set_symbol() and not
> directly called anywhere. To resolve the sparse issues appropriate
> declarations were added in a dedicated purgatory.h file.
> 
> Patch was compile tested with: x86_64_defconfig (implies CONFIG_KEXEC=y)
> 
> Patch is against 4.10-rc2 (localversion-next is next-20170106)
> 
>  arch/x86/purgatory/purgatory.c |  6 +-----
>  arch/x86/purgatory/purgatory.h | 24 ++++++++++++++++++++++++
>  2 files changed, 25 insertions(+), 5 deletions(-)
>  create mode 100644 arch/x86/purgatory/purgatory.h
> 
> diff --git a/arch/x86/purgatory/purgatory.c b/arch/x86/purgatory/purgatory.c
> index 25e068b..9420fe5 100644
> --- a/arch/x86/purgatory/purgatory.c
> +++ b/arch/x86/purgatory/purgatory.c
> @@ -12,11 +12,7 @@
>  
>  #include "sha256.h"
>  #include "../boot/string.h"
> -
> -struct sha_region {
> -	unsigned long start;
> -	unsigned long len;
> -};
> +#include "purgatory.h"
>  
>  unsigned long backup_dest = 0;
>  unsigned long backup_src = 0;
> diff --git a/arch/x86/purgatory/purgatory.h b/arch/x86/purgatory/purgatory.h
> new file mode 100644
> index 0000000..2754e83
> --- /dev/null
> +++ b/arch/x86/purgatory/purgatory.h
> @@ -0,0 +1,24 @@
> +#ifndef BOOT_PURGATORY_H
> +#define BOOT_PURGATORY_H
> +
> +/* This is really just to make sparse happy.
> + * Declaring it all static as sparse suggests is not an option as,
> + * the symbol information is needed. see kexec_purgatory_get_set_symbol()
> + * Technically these prototype and extern declarations are unnecessary
> + */
> +void purgatory(void);
> +int verify_sha256_digest(void);
> +
> +extern unsigned long backup_dest;
> +extern unsigned long backup_src;
> +extern unsigned long backup_sz;
> +
> +struct sha_region {
> +	unsigned long start;
> +	unsigned long len;
> +};
> +
> +extern u8 sha256_digest[];
> +extern struct sha_region sha_regions[];
> +
> +#endif
> -- 
> 2.1.4
> 

Acked-by: Dave Young <dyoung@redhat.com>

Thanks
Dave