[PATCH/RFC] mtd/uclinux: Use generic __bss_stop instead of _ebss

Thu May 31 16:55:39 EDT 2012

The standard (see BSS_SECTION() in <asm-generic/vmlinux.lds.h> and
<asm-generic/sections.h>) symbol for the end of BSS is __bss_stop.
This allows to remove all local declarations that have been added to
several architectures just to please CONFIG_MTD_UCLINUX.

Not-Yet-Signed-off-by: Geert Uytterhoeven <geert at linux-m68k.org>
---
This is a prerequisite for some future m68k changes:
  - replacing the m68k-specific _[se]bss by the generic __bss_{start,stop},
  - using the asm-generic version of <asm/sections.h>.
---
 arch/blackfin/kernel/setup.c              |    1 -
 arch/microblaze/include/asm/sections.h    |    4 ----
 arch/microblaze/kernel/microblaze_ksyms.c |    3 ---
 arch/microblaze/kernel/setup.c            |    4 ++--
 arch/microblaze/kernel/vmlinux.lds.S      |    1 -
 arch/sh/include/asm/sections.h            |    1 -
 arch/sh/kernel/setup.c                    |    2 +-
 arch/sh/kernel/sh_ksyms_32.c              |    1 -
 arch/sh/kernel/vmlinux.lds.S              |    1 -
 arch/sh/lib/mcount.S                      |    8 +++-----
 drivers/mtd/maps/uclinux.c                |    5 ++---
 11 files changed, 8 insertions(+), 23 deletions(-)

diff --git a/arch/blackfin/kernel/setup.c b/arch/blackfin/kernel/setup.c
index ada8f0f..fb96e60 100644
--- a/arch/blackfin/kernel/setup.c
+++ b/arch/blackfin/kernel/setup.c
@@ -52,7 +52,6 @@ EXPORT_SYMBOL(reserved_mem_dcache_on);
 #ifdef CONFIG_MTD_UCLINUX
 extern struct map_info uclinux_ram_map;
 unsigned long memory_mtd_end, memory_mtd_start, mtd_size;
-unsigned long _ebss;
 EXPORT_SYMBOL(memory_mtd_end);
 EXPORT_SYMBOL(memory_mtd_start);
 EXPORT_SYMBOL(mtd_size);
diff --git a/arch/microblaze/include/asm/sections.h b/arch/microblaze/include/asm/sections.h
index 4487e15..c07ed5d 100644
--- a/arch/microblaze/include/asm/sections.h
+++ b/arch/microblaze/include/asm/sections.h
@@ -18,10 +18,6 @@ extern char _ssbss[], _esbss[];
 extern unsigned long __ivt_start[], __ivt_end[];
 extern char _etext[], _stext[];
 
-#  ifdef CONFIG_MTD_UCLINUX
-extern char *_ebss;
-#  endif
-
 extern u32 _fdt_start[], _fdt_end[];
 
 # endif /* !__ASSEMBLY__ */
diff --git a/arch/microblaze/kernel/microblaze_ksyms.c b/arch/microblaze/kernel/microblaze_ksyms.c
index bb4907c..2b25bcf 100644
--- a/arch/microblaze/kernel/microblaze_ksyms.c
+++ b/arch/microblaze/kernel/microblaze_ksyms.c
@@ -21,9 +21,6 @@
 #include <linux/ftrace.h>
 #include <linux/uaccess.h>
 
-extern char *_ebss;
-EXPORT_SYMBOL_GPL(_ebss);
-
 #ifdef CONFIG_FUNCTION_TRACER
 extern void _mcount(void);
 EXPORT_SYMBOL(_mcount);
diff --git a/arch/microblaze/kernel/setup.c b/arch/microblaze/kernel/setup.c
index 16d8dfd..4da971d 100644
--- a/arch/microblaze/kernel/setup.c
+++ b/arch/microblaze/kernel/setup.c
@@ -121,7 +121,7 @@ void __init machine_early_init(const char *cmdline, unsigned int ram,
 
 	/* Move ROMFS out of BSS before clearing it */
 	if (romfs_size > 0) {
-		memmove(&_ebss, (int *)romfs_base, romfs_size);
+		memmove(&__bss_stop, (int *)romfs_base, romfs_size);
 		klimit += romfs_size;
 	}
 #endif
@@ -165,7 +165,7 @@ void __init machine_early_init(const char *cmdline, unsigned int ram,
 	BUG_ON(romfs_size < 0); /* What else can we do? */
 
 	printk("Moved 0x%08x bytes from 0x%08x to 0x%08x\n",
-			romfs_size, romfs_base, (unsigned)&_ebss);
+			romfs_size, romfs_base, (unsigned)&__bss_stop);
 
 	printk("New klimit: 0x%08x\n", (unsigned)klimit);
 #endif
diff --git a/arch/microblaze/kernel/vmlinux.lds.S b/arch/microblaze/kernel/vmlinux.lds.S
index 109e9d8..936d01a 100644
--- a/arch/microblaze/kernel/vmlinux.lds.S
+++ b/arch/microblaze/kernel/vmlinux.lds.S
@@ -131,7 +131,6 @@ SECTIONS {
 			*(COMMON)
 		. = ALIGN (4) ;
 		__bss_stop = . ;
-		_ebss = . ;
 	}
 	. = ALIGN(PAGE_SIZE);
 	_end = .;
diff --git a/arch/sh/include/asm/sections.h b/arch/sh/include/asm/sections.h
index 4a53500..1b61997 100644
--- a/arch/sh/include/asm/sections.h
+++ b/arch/sh/include/asm/sections.h
@@ -6,7 +6,6 @@
 extern long __nosave_begin, __nosave_end;
 extern long __machvec_start, __machvec_end;
 extern char __uncached_start, __uncached_end;
-extern char _ebss[];
 extern char __start_eh_frame[], __stop_eh_frame[];
 
 #endif /* __ASM_SH_SECTIONS_H */
diff --git a/arch/sh/kernel/setup.c b/arch/sh/kernel/setup.c
index 7b57bf1..ebe7a7d 100644
--- a/arch/sh/kernel/setup.c
+++ b/arch/sh/kernel/setup.c
@@ -273,7 +273,7 @@ void __init setup_arch(char **cmdline_p)
 	data_resource.start = virt_to_phys(_etext);
 	data_resource.end = virt_to_phys(_edata)-1;
 	bss_resource.start = virt_to_phys(__bss_start);
-	bss_resource.end = virt_to_phys(_ebss)-1;
+	bss_resource.end = virt_to_phys(__bss_stop)-1;
 
 #ifdef CONFIG_CMDLINE_OVERWRITE
 	strlcpy(command_line, CONFIG_CMDLINE, sizeof(command_line));
diff --git a/arch/sh/kernel/sh_ksyms_32.c b/arch/sh/kernel/sh_ksyms_32.c
index 3896f26..2a0a596 100644
--- a/arch/sh/kernel/sh_ksyms_32.c
+++ b/arch/sh/kernel/sh_ksyms_32.c
@@ -19,7 +19,6 @@ EXPORT_SYMBOL(csum_partial);
 EXPORT_SYMBOL(csum_partial_copy_generic);
 EXPORT_SYMBOL(copy_page);
 EXPORT_SYMBOL(__clear_user);
-EXPORT_SYMBOL(_ebss);
 EXPORT_SYMBOL(empty_zero_page);
 
 #define DECLARE_EXPORT(name)		\
diff --git a/arch/sh/kernel/vmlinux.lds.S b/arch/sh/kernel/vmlinux.lds.S
index c98905f..db88cbf 100644
--- a/arch/sh/kernel/vmlinux.lds.S
+++ b/arch/sh/kernel/vmlinux.lds.S
@@ -78,7 +78,6 @@ SECTIONS
 	. = ALIGN(PAGE_SIZE);
 	__init_end = .;
 	BSS_SECTION(0, PAGE_SIZE, 4)
-	_ebss = .;			/* uClinux MTD sucks */
 	_end = . ;
 
 	STABS_DEBUG
diff --git a/arch/sh/lib/mcount.S b/arch/sh/lib/mcount.S
index 84a5776..60164e6 100644
--- a/arch/sh/lib/mcount.S
+++ b/arch/sh/lib/mcount.S
@@ -39,7 +39,7 @@
  *
  * Make sure the stack pointer contains a valid address. Valid
  * addresses for kernel stacks are anywhere after the bss
- * (after _ebss) and anywhere in init_thread_union (init_stack).
+ * (after __bss_stop) and anywhere in init_thread_union (init_stack).
  */
 #define STACK_CHECK()					\
 	mov	#(THREAD_SIZE >> 10), r0;		\
@@ -60,7 +60,7 @@
 	cmp/hi	r2, r1;					\
 	bf	stack_panic;				\
 							\
-	/* If sp > _ebss then we're OK. */		\
+	/* If sp > __bss_stop then we're OK. */		\
 	mov.l	.L_ebss, r1;				\
 	cmp/hi	r1, r15;				\
 	bt	1f;					\
@@ -70,7 +70,7 @@
 	cmp/hs	r1, r15;				\
 	bf	stack_panic;				\
 							\
-	/* If sp > init_stack && sp < _ebss, not OK. */	\
+	/* If sp > init_stack && sp < __bss_stop, not OK. */	\
 	add	r0, r1;					\
 	cmp/hs	r1, r15;				\
 	bt	stack_panic;				\
@@ -292,8 +292,6 @@ stack_panic:
 	 nop
 
 	.align 2
-.L_ebss:
-	.long	_ebss
 .L_init_thread_union:
 	.long	init_thread_union
 .Lpanic:
diff --git a/drivers/mtd/maps/uclinux.c b/drivers/mtd/maps/uclinux.c
index cfff454..c3bb304 100644
--- a/drivers/mtd/maps/uclinux.c
+++ b/drivers/mtd/maps/uclinux.c
@@ -19,14 +19,13 @@
 #include <linux/mtd/map.h>
 #include <linux/mtd/partitions.h>
 #include <asm/io.h>
+#include <asm/sections.h>
 
 /****************************************************************************/
 
-extern char _ebss;
-
 struct map_info uclinux_ram_map = {
 	.name = "RAM",
-	.phys = (unsigned long)&_ebss,
+	.phys = (unsigned long)__bss_stop,
 	.size = 0,
 };
 
-- 
1.7.0.4


