diff options
| author | Jeff Dike <jdike@addtoit.com> | 2008-02-04 22:31:00 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2008-02-05 09:44:29 -0800 |
| commit | 42a2b54ce8c7b9d4f418995a7950e7e2e15e52ce (patch) | |
| tree | 30bcb0ea0a4ee6d5091b1b9a85589cff8b1863fc /arch/um/include/as-layout.h | |
| parent | b7c000cbc4f1fa7b82efa95b34f00c2adbeaa3fe (diff) | |
uml: clean up TASK_SIZE usage
Clean up the calculation and use of the usable address space size on the host.
task_size is gone, replaced with TASK_SIZE, which is calculated from
CONFIG_TOP_ADDR. get_kmem_end and set_task_sizes_skas are also gone.
host_task_size, which refers to the entire address space usable by the UML
kernel and which may be larger than the address space usable by a UML process,
since that has to end on a pgdir boundary, is replaced by CONFIG_TOP_ADDR.
STACK_TOP is now TASK_SIZE minus the two stub pages.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/um/include/as-layout.h')
| -rw-r--r-- | arch/um/include/as-layout.h | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/arch/um/include/as-layout.h b/arch/um/include/as-layout.h index 2b859e020ac..a2008f550fe 100644 --- a/arch/um/include/as-layout.h +++ b/arch/um/include/as-layout.h @@ -29,9 +29,20 @@ #define _AC(X, Y) __AC(X, Y) #endif +/* + * The "- 1"'s are to avoid gcc complaining about integer overflows + * and unrepresentable decimal constants. With 3-level page tables, + * TASK_SIZE is 0x80000000, which gets turned into its signed decimal + * equivalent in asm-offsets.s. gcc then complains about that being + * unsigned only in C90. To avoid that, UM_TASK_SIZE is defined as + * TASK_SIZE - 1. To compensate, we need to add the 1 back here. + * However, adding it back to UM_TASK_SIZE produces more gcc + * complaints. So, I adjust the thing being subtracted from + * UM_TASK_SIZE instead. Bah. + */ #define STUB_CODE _AC((unsigned long), \ - UML_CONFIG_TOP_ADDR - 2 * UM_KERN_PAGE_SIZE) -#define STUB_DATA _AC((unsigned long), UML_CONFIG_TOP_ADDR - UM_KERN_PAGE_SIZE) + UM_TASK_SIZE - (2 * UM_KERN_PAGE_SIZE - 1)) +#define STUB_DATA _AC((unsigned long), UM_TASK_SIZE - (UM_KERN_PAGE_SIZE - 1)) #define STUB_START _AC(, STUB_CODE) #ifndef __ASSEMBLY__ |