[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>
This commit is contained in:
Atsushi Nemoto 2006-10-26 00:08:31 +09:00 committed by Ralf Baechle
parent 56ae583330
commit 656be92f9a
7 changed files with 94 additions and 3 deletions

View File

@ -63,9 +63,7 @@ cflags-y += -mabi=64
ifdef CONFIG_BUILD_ELF64
cflags-y += $(call cc-option,-mno-explicit-relocs)
else
# -msym32 can not be used for modules since they are loaded into XKSEG
CFLAGS_MODULE += $(call cc-option,-mno-explicit-relocs)
CFLAGS_KERNEL += $(call cc-option,-msym32)
cflags-y += $(call cc-option,-msym32)
endif
endif

View File

@ -250,6 +250,9 @@ NESTED(smp_bootstrap, 16, sp)
*/
page swapper_pg_dir, _PGD_ORDER
#ifdef CONFIG_64BIT
#if defined(CONFIG_MODULES) && !defined(CONFIG_BUILD_ELF64)
page module_pg_dir, _PGD_ORDER
#endif
page invalid_pmd_table, _PMD_ORDER
#endif
page invalid_pte_table, _PTE_ORDER

View File

@ -29,6 +29,7 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <asm/pgtable.h> /* MODULE_START */
struct mips_hi16 {
struct mips_hi16 *next;
@ -43,9 +44,23 @@ static DEFINE_SPINLOCK(dbe_lock);
void *module_alloc(unsigned long size)
{
#ifdef MODULE_START
struct vm_struct *area;
size = PAGE_ALIGN(size);
if (!size)
return NULL;
area = __get_vm_area(size, VM_ALLOC, MODULE_START, MODULE_END);
if (!area)
return NULL;
return __vmalloc_area(area, GFP_KERNEL, PAGE_KERNEL);
#else
if (size == 0)
return NULL;
return vmalloc(size);
#endif
}
/* Free memory returned from module_alloc */

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@ -60,6 +60,10 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long write,
*/
if (unlikely(address >= VMALLOC_START && address <= VMALLOC_END))
goto vmalloc_fault;
#ifdef MODULE_START
if (unlikely(address >= MODULE_START && address < MODULE_END))
goto vmalloc_fault;
#endif
/*
* If we're in an interrupt or have no user

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@ -58,6 +58,9 @@ void __init pagetable_init(void)
/* Initialize the entire pgd. */
pgd_init((unsigned long)swapper_pg_dir);
#ifdef MODULE_START
pgd_init((unsigned long)module_pg_dir);
#endif
pmd_init((unsigned long)invalid_pmd_table, (unsigned long)invalid_pte_table);
pgd_base = swapper_pg_dir;

View File

@ -423,6 +423,9 @@ enum label_id {
label_invalid,
label_second_part,
label_leave,
#ifdef MODULE_START
label_module_alloc,
#endif
label_vmalloc,
label_vmalloc_done,
label_tlbw_hazard,
@ -455,6 +458,9 @@ static __init void build_label(struct label **lab, u32 *addr,
L_LA(_second_part)
L_LA(_leave)
#ifdef MODULE_START
L_LA(_module_alloc)
#endif
L_LA(_vmalloc)
L_LA(_vmalloc_done)
L_LA(_tlbw_hazard)
@ -686,6 +692,13 @@ static void __init il_bgezl(u32 **p, struct reloc **r, unsigned int reg,
i_bgezl(p, reg, 0);
}
static void __init __attribute__((unused))
il_bgez(u32 **p, struct reloc **r, unsigned int reg, enum label_id l)
{
r_mips_pc16(r, *p, l);
i_bgez(p, reg, 0);
}
/* The only general purpose registers allowed in TLB handlers. */
#define K0 26
#define K1 27
@ -970,7 +983,11 @@ build_get_pmde64(u32 **p, struct label **l, struct reloc **r,
* The vmalloc handling is not in the hotpath.
*/
i_dmfc0(p, tmp, C0_BADVADDR);
#ifdef MODULE_START
il_bltz(p, r, tmp, label_module_alloc);
#else
il_bltz(p, r, tmp, label_vmalloc);
#endif
/* No i_nop needed here, since the next insn doesn't touch TMP. */
#ifdef CONFIG_SMP
@ -1023,8 +1040,46 @@ build_get_pgd_vmalloc64(u32 **p, struct label **l, struct reloc **r,
{
long swpd = (long)swapper_pg_dir;
#ifdef MODULE_START
long modd = (long)module_pg_dir;
l_module_alloc(l, *p);
/*
* Assumption:
* VMALLOC_START >= 0xc000000000000000UL
* MODULE_START >= 0xe000000000000000UL
*/
i_SLL(p, ptr, bvaddr, 2);
il_bgez(p, r, ptr, label_vmalloc);
if (in_compat_space_p(MODULE_START) && !rel_lo(MODULE_START)) {
i_lui(p, ptr, rel_hi(MODULE_START)); /* delay slot */
} else {
/* unlikely configuration */
i_nop(p); /* delay slot */
i_LA(p, ptr, MODULE_START);
}
i_dsubu(p, bvaddr, bvaddr, ptr);
if (in_compat_space_p(modd) && !rel_lo(modd)) {
il_b(p, r, label_vmalloc_done);
i_lui(p, ptr, rel_hi(modd));
} else {
i_LA_mostly(p, ptr, modd);
il_b(p, r, label_vmalloc_done);
i_daddiu(p, ptr, ptr, rel_lo(modd));
}
l_vmalloc(l, *p);
if (in_compat_space_p(MODULE_START) && !rel_lo(MODULE_START) &&
MODULE_START << 32 == VMALLOC_START)
i_dsll32(p, ptr, ptr, 0); /* typical case */
else
i_LA(p, ptr, VMALLOC_START);
#else
l_vmalloc(l, *p);
i_LA(p, ptr, VMALLOC_START);
#endif
i_dsubu(p, bvaddr, bvaddr, ptr);
if (in_compat_space_p(swpd) && !rel_lo(swpd)) {

View File

@ -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 @@ static inline void pud_clear(pud_t *pudp)
#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))