x86, vmlinux.lds: unify data output sections

For 64 bit the following functional changes are introduced:

 - .data.page_aligned has moved
 - .data.cacheline_aligned has moved
 - .data.read_mostly has moved
 - ALIGN() moved out of output section for .data.cacheline_aligned
 - ALIGN() moved out of output section for .data.page_aligned

Notice that 32 bit and 64 bit has different location of _edata.
.data_nosave is 32 bit only as 64 bit is special due to PERCPU.

[ Impact: 32-bit: cleanup, 64-bit: use 32-bit linker script ]

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Tim Abbott <tabbott@MIT.EDU>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <1240991249-27117-7-git-send-email-sam@ravnborg.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 55 insertions, 0 deletions

diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
index 67164f6f092f..067bdb012dad 100644
--- a/arch/x86/kernel/vmlinux.lds.S
+++ b/arch/x86/kernel/vmlinux.lds.S
@@ -104,6 +104,61 @@ SECTIONS
 
         RODATA
 
+        /* Data */
+        . = ALIGN(PAGE_SIZE);
+        .data : AT(ADDR(.data) - LOAD_OFFSET) {
+                DATA_DATA
+                CONSTRUCTORS
+
+#ifdef CONFIG_X86_64
+                /* End of data section */
+                _edata = .;
+#endif
+        } :data
+
+#ifdef CONFIG_X86_32
+        /* 32 bit has nosave before _edata */
+        . = ALIGN(PAGE_SIZE);
+        .data_nosave : AT(ADDR(.data_nosave) - LOAD_OFFSET) {
+                __nosave_begin = .;
+                *(.data.nosave)
+                . = ALIGN(PAGE_SIZE);
+                __nosave_end = .;
+        }
+#endif
+
+        . = ALIGN(PAGE_SIZE);
+        .data.page_aligned : AT(ADDR(.data.page_aligned) - LOAD_OFFSET) {
+                *(.data.page_aligned)
+                *(.data.idt)
+        }
+
+#ifdef CONFIG_X86_32
+        . = ALIGN(32);
+#else
+        . = ALIGN(PAGE_SIZE);
+        . = ALIGN(CONFIG_X86_L1_CACHE_BYTES);
+#endif
+        .data.cacheline_aligned :
+                AT(ADDR(.data.cacheline_aligned) - LOAD_OFFSET) {
+                *(.data.cacheline_aligned)
+        }
+
+        /* rarely changed data like cpu maps */
+#ifdef CONFIG_X86_32
+        . = ALIGN(32);
+#else
+        . = ALIGN(CONFIG_X86_INTERNODE_CACHE_BYTES);
+#endif
+        .data.read_mostly : AT(ADDR(.data.read_mostly) - LOAD_OFFSET) {
+                *(.data.read_mostly)
+
+#ifdef CONFIG_X86_32
+                /* End of data section */
+                _edata = .;
+#endif
+        }
+
 
 #ifdef CONFIG_X86_32
 # include "vmlinux_32.lds.S"