[MIPS] Load modules to CKSEG0 if CONFIG_BUILD_ELF64=n
This is a patch to load 64-bit modules to CKSEG0 so that can be
compiled with -msym32 option. This makes each module ~10% smaller.
* introduce MODULE_START and MODULE_END
* custom module_alloc()
* PGD for modules
* change XTLB refill handler synthesizer
* enable -msym32 for modules again
(revert ca78b1a5c6a6e70e052d3ea253828e49b5d07c8a)
New XTLB refill handler looks like this:
80000080 dmfc0 k0,C0_BADVADDR
80000084 bltz k0,800000e4 # goto l_module_alloc
80000088 lui k1,0x8046 # %high(pgd_current)
8000008c ld k1,24600(k1) # %low(pgd_current)
80000090 dsrl k0,k0,0x1b # l_vmalloc_done:
80000094 andi k0,k0,0x1ff8
80000098 daddu k1,k1,k0
8000009c dmfc0 k0,C0_BADVADDR
800000a0 ld k1,0(k1)
800000a4 dsrl k0,k0,0x12
800000a8 andi k0,k0,0xff8
800000ac daddu k1,k1,k0
800000b0 dmfc0 k0,C0_XCONTEXT
800000b4 ld k1,0(k1)
800000b8 andi k0,k0,0xff0
800000bc daddu k1,k1,k0
800000c0 ld k0,0(k1)
800000c4 ld k1,8(k1)
800000c8 dsrl k0,k0,0x6
800000cc mtc0 k0,C0_ENTRYLO0
800000d0 dsrl k1,k1,0x6
800000d4 mtc0 k1,C0_ENTRYL01
800000d8 nop
800000dc tlbwr
800000e0 eret
800000e4 dsll k1,k0,0x2 # l_module_alloc:
800000e8 bgez k1,80000008 # goto l_vmalloc
800000ec lui k1,0xc000
800000f0 dsubu k0,k0,k1
800000f4 lui k1,0x8046 # %high(module_pg_dir)
800000f8 beq zero,zero,80000000
800000fc nop
80000000 beq zero,zero,80000090 # goto l_vmalloc_done
80000004 daddiu k1,k1,0x4000
80000008 dsll32 k1,k1,0x0 # l_vmalloc:
8000000c dsubu k0,k0,k1
80000010 beq zero,zero,80000090 # goto l_vmalloc_done
80000014 lui k1,0x8046 # %high(swapper_pg_dir)
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/include/asm-mips/pgtable-64.h b/include/asm-mips/pgtable-64.h
index 7e73203..b9b1e86 100644
--- a/include/asm-mips/pgtable-64.h
+++ b/include/asm-mips/pgtable-64.h
@@ -14,6 +14,7 @@
#include <asm/addrspace.h>
#include <asm/page.h>
#include <asm/cachectl.h>
+#include <asm/fixmap.h>
#include <asm-generic/pgtable-nopud.h>
@@ -103,6 +104,13 @@
#define VMALLOC_START MAP_BASE
#define VMALLOC_END \
(VMALLOC_START + PTRS_PER_PGD * PTRS_PER_PMD * PTRS_PER_PTE * PAGE_SIZE)
+#if defined(CONFIG_MODULES) && !defined(CONFIG_BUILD_ELF64) && \
+ VMALLOC_START != CKSSEG
+/* Load modules into 32bit-compatible segment. */
+#define MODULE_START CKSSEG
+#define MODULE_END (FIXADDR_START-2*PAGE_SIZE)
+extern pgd_t module_pg_dir[PTRS_PER_PGD];
+#endif
#define pte_ERROR(e) \
printk("%s:%d: bad pte %016lx.\n", __FILE__, __LINE__, pte_val(e))
@@ -174,7 +182,12 @@
#define __pmd_offset(address) pmd_index(address)
/* to find an entry in a kernel page-table-directory */
+#ifdef MODULE_START
+#define pgd_offset_k(address) \
+ ((address) >= MODULE_START ? module_pg_dir : pgd_offset(&init_mm, 0UL))
+#else
#define pgd_offset_k(address) pgd_offset(&init_mm, 0UL)
+#endif
#define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
#define pmd_index(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))