void system_reset_exception(struct pt_regs *regs);
void machine_check_exception(struct pt_regs *regs);
void emulation_assist_interrupt(struct pt_regs *regs);
+long do_slb_fault(struct pt_regs *regs, unsigned long ea);
+void do_bad_slb_fault(struct pt_regs *regs, unsigned long ea, long err);
/* signals, syscalls and interrupts */
long sys_swapcontext(struct ucontext __user *old_ctx,
*/
#define MAX_MCE_DEPTH 4
-/*
- * EX_LR is only used in EXSLB and where it does not overlap with EX_DAR
- * EX_CCR similarly with DSISR, but being 4 byte registers there is a hole
- * in the save area so it's not necessary to overlap them. Could be used
- * for future savings though if another 4 byte register was to be saved.
- */
-#define EX_LR EX_DAR
-
/*
* EX_R3 is only used by the bad_stack handler. bad_stack reloads and
* saves DAR from SPRN_DAR, and EX_DAR is not used. So EX_R3 can overlap
EXC_REAL_BEGIN(data_access_slb, 0x380, 0x80)
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXSLB)
- EXCEPTION_PROLOG_1(PACA_EXSLB, KVMTEST_PR, 0x380)
- mr r12,r3 /* save r3 */
- mfspr r3,SPRN_DAR
- mfspr r11,SPRN_SRR1
- crset 4*cr6+eq
- BRANCH_TO_COMMON(r10, slb_miss_common)
+EXCEPTION_PROLOG(PACA_EXSLB, data_access_slb_common, EXC_STD, KVMTEST_PR, 0x380);
EXC_REAL_END(data_access_slb, 0x380, 0x80)
EXC_VIRT_BEGIN(data_access_slb, 0x4380, 0x80)
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXSLB)
- EXCEPTION_PROLOG_1(PACA_EXSLB, NOTEST, 0x380)
- mr r12,r3 /* save r3 */
- mfspr r3,SPRN_DAR
- mfspr r11,SPRN_SRR1
- crset 4*cr6+eq
- BRANCH_TO_COMMON(r10, slb_miss_common)
+EXCEPTION_RELON_PROLOG(PACA_EXSLB, data_access_slb_common, EXC_STD, NOTEST, 0x380);
EXC_VIRT_END(data_access_slb, 0x4380, 0x80)
+
TRAMP_KVM_SKIP(PACA_EXSLB, 0x380)
+EXC_COMMON_BEGIN(data_access_slb_common)
+ mfspr r10,SPRN_DAR
+ std r10,PACA_EXSLB+EX_DAR(r13)
+ EXCEPTION_PROLOG_COMMON(0x380, PACA_EXSLB)
+ ld r4,PACA_EXSLB+EX_DAR(r13)
+ std r4,_DAR(r1)
+ addi r3,r1,STACK_FRAME_OVERHEAD
+ bl do_slb_fault
+ cmpdi r3,0
+ bne- 1f
+ b fast_exception_return
+1: /* Error case */
+ std r3,RESULT(r1)
+ bl save_nvgprs
+ RECONCILE_IRQ_STATE(r10, r11)
+ ld r4,_DAR(r1)
+ ld r5,RESULT(r1)
+ addi r3,r1,STACK_FRAME_OVERHEAD
+ bl do_bad_slb_fault
+ b ret_from_except
+
EXC_REAL(instruction_access, 0x400, 0x80)
EXC_VIRT(instruction_access, 0x4400, 0x80, 0x400)
EXC_REAL_BEGIN(instruction_access_slb, 0x480, 0x80)
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXSLB)
- EXCEPTION_PROLOG_1(PACA_EXSLB, KVMTEST_PR, 0x480)
- mr r12,r3 /* save r3 */
- mfspr r3,SPRN_SRR0 /* SRR0 is faulting address */
- mfspr r11,SPRN_SRR1
- crclr 4*cr6+eq
- BRANCH_TO_COMMON(r10, slb_miss_common)
+EXCEPTION_PROLOG(PACA_EXSLB, instruction_access_slb_common, EXC_STD, KVMTEST_PR, 0x480);
EXC_REAL_END(instruction_access_slb, 0x480, 0x80)
EXC_VIRT_BEGIN(instruction_access_slb, 0x4480, 0x80)
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXSLB)
- EXCEPTION_PROLOG_1(PACA_EXSLB, NOTEST, 0x480)
- mr r12,r3 /* save r3 */
- mfspr r3,SPRN_SRR0 /* SRR0 is faulting address */
- mfspr r11,SPRN_SRR1
- crclr 4*cr6+eq
- BRANCH_TO_COMMON(r10, slb_miss_common)
+EXCEPTION_RELON_PROLOG(PACA_EXSLB, instruction_access_slb_common, EXC_STD, NOTEST, 0x480);
EXC_VIRT_END(instruction_access_slb, 0x4480, 0x80)
-TRAMP_KVM(PACA_EXSLB, 0x480)
-
-
-/*
- * This handler is used by the 0x380 and 0x480 SLB miss interrupts, as well as
- * the virtual mode 0x4380 and 0x4480 interrupts if AIL is enabled.
- */
-EXC_COMMON_BEGIN(slb_miss_common)
- /*
- * r13 points to the PACA, r9 contains the saved CR,
- * r12 contains the saved r3,
- * r11 contain the saved SRR1, SRR0 is still ready for return
- * r3 has the faulting address
- * r9 - r13 are saved in paca->exslb.
- * cr6.eq is set for a D-SLB miss, clear for a I-SLB miss
- * We assume we aren't going to take any exceptions during this
- * procedure.
- */
- mflr r10
- stw r9,PACA_EXSLB+EX_CCR(r13) /* save CR in exc. frame */
- std r10,PACA_EXSLB+EX_LR(r13) /* save LR */
-
- andi. r9,r11,MSR_PR // Check for exception from userspace
- cmpdi cr4,r9,MSR_PR // And save the result in CR4 for later
-
- /*
- * Test MSR_RI before calling slb_allocate_realmode, because the
- * MSR in r11 gets clobbered. However we still want to allocate
- * SLB in case MSR_RI=0, to minimise the risk of getting stuck in
- * recursive SLB faults. So use cr5 for this, which is preserved.
- */
- andi. r11,r11,MSR_RI /* check for unrecoverable exception */
- cmpdi cr5,r11,MSR_RI
-
- crset 4*cr0+eq
-#ifdef CONFIG_PPC_BOOK3S_64
-BEGIN_MMU_FTR_SECTION
- bl slb_allocate
-END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_RADIX)
-#endif
-
- ld r10,PACA_EXSLB+EX_LR(r13)
- lwz r9,PACA_EXSLB+EX_CCR(r13) /* get saved CR */
- mtlr r10
-
- /*
- * Large address, check whether we have to allocate new contexts.
- */
- beq- 8f
- bne- cr5,2f /* if unrecoverable exception, oops */
-
- /* All done -- return from exception. */
-
- bne cr4,1f /* returning to kernel */
-
- mtcrf 0x80,r9
- mtcrf 0x08,r9 /* MSR[PR] indication is in cr4 */
- mtcrf 0x04,r9 /* MSR[RI] indication is in cr5 */
- mtcrf 0x02,r9 /* I/D indication is in cr6 */
- mtcrf 0x01,r9 /* slb_allocate uses cr0 and cr7 */
-
- RESTORE_CTR(r9, PACA_EXSLB)
- RESTORE_PPR_PACA(PACA_EXSLB, r9)
- mr r3,r12
- ld r9,PACA_EXSLB+EX_R9(r13)
- ld r10,PACA_EXSLB+EX_R10(r13)
- ld r11,PACA_EXSLB+EX_R11(r13)
- ld r12,PACA_EXSLB+EX_R12(r13)
- ld r13,PACA_EXSLB+EX_R13(r13)
- RFI_TO_USER
- b . /* prevent speculative execution */
-1:
- mtcrf 0x80,r9
- mtcrf 0x08,r9 /* MSR[PR] indication is in cr4 */
- mtcrf 0x04,r9 /* MSR[RI] indication is in cr5 */
- mtcrf 0x02,r9 /* I/D indication is in cr6 */
- mtcrf 0x01,r9 /* slb_allocate uses cr0 and cr7 */
-
- RESTORE_CTR(r9, PACA_EXSLB)
- RESTORE_PPR_PACA(PACA_EXSLB, r9)
- mr r3,r12
- ld r9,PACA_EXSLB+EX_R9(r13)
- ld r10,PACA_EXSLB+EX_R10(r13)
- ld r11,PACA_EXSLB+EX_R11(r13)
- ld r12,PACA_EXSLB+EX_R12(r13)
- ld r13,PACA_EXSLB+EX_R13(r13)
- RFI_TO_KERNEL
- b . /* prevent speculative execution */
-
-
-2: std r3,PACA_EXSLB+EX_DAR(r13)
- mr r3,r12
- mfspr r11,SPRN_SRR0
- mfspr r12,SPRN_SRR1
- LOAD_HANDLER(r10,unrecov_slb)
- mtspr SPRN_SRR0,r10
- ld r10,PACAKMSR(r13)
- mtspr SPRN_SRR1,r10
- RFI_TO_KERNEL
- b .
-
-8: std r3,PACA_EXSLB+EX_DAR(r13)
- mr r3,r12
- mfspr r11,SPRN_SRR0
- mfspr r12,SPRN_SRR1
- LOAD_HANDLER(r10, large_addr_slb)
- mtspr SPRN_SRR0,r10
- ld r10,PACAKMSR(r13)
- mtspr SPRN_SRR1,r10
- RFI_TO_KERNEL
- b .
+TRAMP_KVM(PACA_EXSLB, 0x480)
-EXC_COMMON_BEGIN(unrecov_slb)
- EXCEPTION_PROLOG_COMMON(0x4100, PACA_EXSLB)
- RECONCILE_IRQ_STATE(r10, r11)
+EXC_COMMON_BEGIN(instruction_access_slb_common)
+ EXCEPTION_PROLOG_COMMON(0x480, PACA_EXSLB)
+ ld r4,_NIP(r1)
+ addi r3,r1,STACK_FRAME_OVERHEAD
+ bl do_slb_fault
+ cmpdi r3,0
+ bne- 1f
+ b fast_exception_return
+1: /* Error case */
+ std r3,RESULT(r1)
bl save_nvgprs
-1: addi r3,r1,STACK_FRAME_OVERHEAD
- bl unrecoverable_exception
- b 1b
-
-EXC_COMMON_BEGIN(large_addr_slb)
- EXCEPTION_PROLOG_COMMON(0x380, PACA_EXSLB)
RECONCILE_IRQ_STATE(r10, r11)
- ld r3, PACA_EXSLB+EX_DAR(r13)
- std r3, _DAR(r1)
- beq cr6, 2f
- li r10, 0x481 /* fix trap number for I-SLB miss */
- std r10, _TRAP(r1)
-2: bl save_nvgprs
- addi r3, r1, STACK_FRAME_OVERHEAD
- bl slb_miss_large_addr
+ ld r4,_NIP(r1)
+ ld r5,RESULT(r1)
+ addi r3,r1,STACK_FRAME_OVERHEAD
+ bl do_bad_slb_fault
b ret_from_except
+
EXC_REAL_BEGIN(hardware_interrupt, 0x500, 0x100)
.globl hardware_interrupt_hv;
hardware_interrupt_hv:
ccflags-$(CONFIG_PPC64) := $(NO_MINIMAL_TOC)
+CFLAGS_REMOVE_slb.o = $(CC_FLAGS_FTRACE)
+
obj-y := fault.o mem.o pgtable.o mmap.o \
init_$(BITS).o pgtable_$(BITS).o \
init-common.o mmu_context.o drmem.o
obj-$(CONFIG_PPC_BOOK3E) += tlb_low_$(BITS)e.o
hash64-$(CONFIG_PPC_NATIVE) := hash_native_64.o
obj-$(CONFIG_PPC_BOOK3E_64) += pgtable-book3e.o
-obj-$(CONFIG_PPC_BOOK3S_64) += pgtable-hash64.o hash_utils_64.o slb_low.o slb.o $(hash64-y) mmu_context_book3s64.o pgtable-book3s64.o
+obj-$(CONFIG_PPC_BOOK3S_64) += pgtable-hash64.o hash_utils_64.o slb.o $(hash64-y) mmu_context_book3s64.o pgtable-book3s64.o
obj-$(CONFIG_PPC_RADIX_MMU) += pgtable-radix.o tlb-radix.o
obj-$(CONFIG_PPC_STD_MMU_32) += ppc_mmu_32.o hash_low_32.o mmu_context_hash32.o
obj-$(CONFIG_PPC_STD_MMU) += tlb_hash$(BITS).o
* 2 of the License, or (at your option) any later version.
*/
+#include <asm/asm-prototypes.h>
#include <asm/pgtable.h>
#include <asm/mmu.h>
#include <asm/mmu_context.h>
KSTACK_INDEX = 1, /* Kernel stack map */
};
-extern void slb_allocate(unsigned long ea);
+static long slb_allocate_user(struct mm_struct *mm, unsigned long ea);
#define slb_esid_mask(ssize) \
(((ssize) == MMU_SEGSIZE_256M)? ESID_MASK: ESID_MASK_1T)
return (ea & slb_esid_mask(ssize)) | SLB_ESID_V | index;
}
-static inline unsigned long mk_vsid_data(unsigned long ea, int ssize,
+static inline unsigned long __mk_vsid_data(unsigned long vsid, int ssize,
unsigned long flags)
{
- return (get_kernel_vsid(ea, ssize) << slb_vsid_shift(ssize)) | flags |
+ return (vsid << slb_vsid_shift(ssize)) | flags |
((unsigned long) ssize << SLB_VSID_SSIZE_SHIFT);
}
+static inline unsigned long mk_vsid_data(unsigned long ea, int ssize,
+ unsigned long flags)
+{
+ return __mk_vsid_data(get_kernel_vsid(ea, ssize), ssize, flags);
+}
+
static inline void slb_shadow_update(unsigned long ea, int ssize,
unsigned long flags,
enum slb_index index)
is_kernel_addr(exec_base))
return;
- slb_allocate(pc);
+ slb_allocate_user(mm, pc);
if (!esids_match(pc, stack))
- slb_allocate(stack);
+ slb_allocate_user(mm, stack);
if (!esids_match(pc, exec_base) &&
!esids_match(stack, exec_base))
- slb_allocate(exec_base);
-}
-
-static inline void patch_slb_encoding(unsigned int *insn_addr,
- unsigned int immed)
-{
-
- /*
- * This function patches either an li or a cmpldi instruction with
- * a new immediate value. This relies on the fact that both li
- * (which is actually addi) and cmpldi both take a 16-bit immediate
- * value, and it is situated in the same location in the instruction,
- * ie. bits 16-31 (Big endian bit order) or the lower 16 bits.
- * The signedness of the immediate operand differs between the two
- * instructions however this code is only ever patching a small value,
- * much less than 1 << 15, so we can get away with it.
- * To patch the value we read the existing instruction, clear the
- * immediate value, and or in our new value, then write the instruction
- * back.
- */
- unsigned int insn = (*insn_addr & 0xffff0000) | immed;
- patch_instruction(insn_addr, insn);
+ slb_allocate_user(mm, exec_base);
}
-extern u32 slb_miss_kernel_load_linear[];
-extern u32 slb_miss_kernel_load_io[];
-extern u32 slb_compare_rr_to_size[];
-extern u32 slb_miss_kernel_load_vmemmap[];
-
void slb_set_size(u16 size)
{
- if (mmu_slb_size == size)
- return;
-
mmu_slb_size = size;
- patch_slb_encoding(slb_compare_rr_to_size, mmu_slb_size);
}
void slb_initialize(void)
#endif
if (!slb_encoding_inited) {
slb_encoding_inited = 1;
- patch_slb_encoding(slb_miss_kernel_load_linear,
- SLB_VSID_KERNEL | linear_llp);
- patch_slb_encoding(slb_miss_kernel_load_io,
- SLB_VSID_KERNEL | io_llp);
- patch_slb_encoding(slb_compare_rr_to_size,
- mmu_slb_size);
-
pr_devel("SLB: linear LLP = %04lx\n", linear_llp);
pr_devel("SLB: io LLP = %04lx\n", io_llp);
-
#ifdef CONFIG_SPARSEMEM_VMEMMAP
- patch_slb_encoding(slb_miss_kernel_load_vmemmap,
- SLB_VSID_KERNEL | vmemmap_llp);
pr_devel("SLB: vmemmap LLP = %04lx\n", vmemmap_llp);
#endif
}
asm volatile("isync":::"memory");
}
-static void insert_slb_entry(unsigned long vsid, unsigned long ea,
- int bpsize, int ssize)
+static void slb_cache_update(unsigned long esid_data)
{
- unsigned long flags, vsid_data, esid_data;
- enum slb_index index;
int slb_cache_index;
if (cpu_has_feature(CPU_FTR_ARCH_300))
return; /* ISAv3.0B and later does not use slb_cache */
/*
- * We are irq disabled, hence should be safe to access PACA.
+ * Now update slb cache entries
*/
- VM_WARN_ON(!irqs_disabled());
+ slb_cache_index = local_paca->slb_cache_ptr;
+ if (slb_cache_index < SLB_CACHE_ENTRIES) {
+ /*
+ * We have space in slb cache for optimized switch_slb().
+ * Top 36 bits from esid_data as per ISA
+ */
+ local_paca->slb_cache[slb_cache_index++] = esid_data >> 28;
+ local_paca->slb_cache_ptr++;
+ } else {
+ /*
+ * Our cache is full and the current cache content strictly
+ * doesn't indicate the active SLB conents. Bump the ptr
+ * so that switch_slb() will ignore the cache.
+ */
+ local_paca->slb_cache_ptr = SLB_CACHE_ENTRIES + 1;
+ }
+}
- /*
- * We can't take a PMU exception in the following code, so hard
- * disable interrupts.
- */
- hard_irq_disable();
+static enum slb_index alloc_slb_index(void)
+{
+ enum slb_index index;
+ /* round-robin replacement of slb starting at SLB_NUM_BOLTED. */
index = get_paca()->stab_rr;
-
- /*
- * simple round-robin replacement of slb starting at SLB_NUM_BOLTED.
- */
if (index < (mmu_slb_size - 1))
index++;
else
index = SLB_NUM_BOLTED;
-
get_paca()->stab_rr = index;
- flags = SLB_VSID_USER | mmu_psize_defs[bpsize].sllp;
- vsid_data = (vsid << slb_vsid_shift(ssize)) | flags |
- ((unsigned long) ssize << SLB_VSID_SSIZE_SHIFT);
+ return index;
+}
+
+static long slb_insert_entry(unsigned long ea, unsigned long context,
+ unsigned long flags, int ssize, bool kernel)
+{
+ unsigned long vsid;
+ unsigned long vsid_data, esid_data;
+ enum slb_index index;
+
+ vsid = get_vsid(context, ea, ssize);
+ if (!vsid)
+ return -EFAULT;
+
+ /*
+ * There must not be a kernel SLB fault in alloc_slb_index or before
+ * slbmte here or the allocation bitmaps could get out of whack with
+ * the SLB.
+ *
+ * User SLB faults or preloads take this path which might get inlined
+ * into the caller, so add compiler barriers here to ensure unsafe
+ * memory accesses do not come between.
+ */
+ barrier();
+
+ index = alloc_slb_index();
+
+ vsid_data = __mk_vsid_data(vsid, ssize, flags);
esid_data = mk_esid_data(ea, ssize, index);
/*
* No need for an isync before or after this slbmte. The exception
* we enter with and the rfid we exit with are context synchronizing.
- * Also we only handle user segments here.
+ * User preloads should add isync afterwards in case the kernel
+ * accesses user memory before it returns to userspace with rfid.
*/
- asm volatile("slbmte %0, %1" : : "r" (vsid_data), "r" (esid_data)
- : "memory");
+ asm volatile("slbmte %0, %1" : : "r" (vsid_data), "r" (esid_data));
- /*
- * Now update slb cache entries
- */
- slb_cache_index = get_paca()->slb_cache_ptr;
- if (slb_cache_index < SLB_CACHE_ENTRIES) {
- /*
- * We have space in slb cache for optimized switch_slb().
- * Top 36 bits from esid_data as per ISA
- */
- get_paca()->slb_cache[slb_cache_index++] = esid_data >> 28;
- get_paca()->slb_cache_ptr++;
+ barrier();
+
+ if (!kernel)
+ slb_cache_update(esid_data);
+
+ return 0;
+}
+
+static long slb_allocate_kernel(unsigned long ea, unsigned long id)
+{
+ unsigned long context;
+ unsigned long flags;
+ int ssize;
+
+ if ((ea & ~REGION_MASK) >= (1ULL << MAX_EA_BITS_PER_CONTEXT))
+ return -EFAULT;
+
+ if (id == KERNEL_REGION_ID) {
+ flags = SLB_VSID_KERNEL | mmu_psize_defs[mmu_linear_psize].sllp;
+#ifdef CONFIG_SPARSEMEM_VMEMMAP
+ } else if (id == VMEMMAP_REGION_ID) {
+ flags = SLB_VSID_KERNEL | mmu_psize_defs[mmu_vmemmap_psize].sllp;
+#endif
+ } else if (id == VMALLOC_REGION_ID) {
+ if (ea < H_VMALLOC_END)
+ flags = get_paca()->vmalloc_sllp;
+ else
+ flags = SLB_VSID_KERNEL | mmu_psize_defs[mmu_io_psize].sllp;
} else {
- /*
- * Our cache is full and the current cache content strictly
- * doesn't indicate the active SLB conents. Bump the ptr
- * so that switch_slb() will ignore the cache.
- */
- get_paca()->slb_cache_ptr = SLB_CACHE_ENTRIES + 1;
+ return -EFAULT;
}
+
+ ssize = MMU_SEGSIZE_1T;
+ if (!mmu_has_feature(MMU_FTR_1T_SEGMENT))
+ ssize = MMU_SEGSIZE_256M;
+
+ context = id - KERNEL_REGION_CONTEXT_OFFSET;
+
+ return slb_insert_entry(ea, context, flags, ssize, true);
}
-static void handle_multi_context_slb_miss(int context_id, unsigned long ea)
+static long slb_allocate_user(struct mm_struct *mm, unsigned long ea)
{
- struct mm_struct *mm = current->mm;
- unsigned long vsid;
+ unsigned long context;
+ unsigned long flags;
int bpsize;
+ int ssize;
/*
- * We are always above 1TB, hence use high user segment size.
+ * consider this as bad access if we take a SLB miss
+ * on an address above addr limit.
*/
- vsid = get_vsid(context_id, ea, mmu_highuser_ssize);
+ if (ea >= mm->context.slb_addr_limit)
+ return -EFAULT;
+
+ context = get_ea_context(&mm->context, ea);
+ if (!context)
+ return -EFAULT;
+
+ if (unlikely(ea >= H_PGTABLE_RANGE)) {
+ WARN_ON(1);
+ return -EFAULT;
+ }
+
+ ssize = user_segment_size(ea);
+
bpsize = get_slice_psize(mm, ea);
- insert_slb_entry(vsid, ea, bpsize, mmu_highuser_ssize);
+ flags = SLB_VSID_USER | mmu_psize_defs[bpsize].sllp;
+
+ return slb_insert_entry(ea, context, flags, ssize, false);
}
-void slb_miss_large_addr(struct pt_regs *regs)
+long do_slb_fault(struct pt_regs *regs, unsigned long ea)
{
- enum ctx_state prev_state = exception_enter();
- unsigned long ea = regs->dar;
- int context;
+ unsigned long id = REGION_ID(ea);
- if (REGION_ID(ea) != USER_REGION_ID)
- goto slb_bad_addr;
+ /* IRQs are not reconciled here, so can't check irqs_disabled */
+ VM_WARN_ON(mfmsr() & MSR_EE);
- /*
- * Are we beyound what the page table layout supports ?
- */
- if ((ea & ~REGION_MASK) >= H_PGTABLE_RANGE)
- goto slb_bad_addr;
-
- /* Lower address should have been handled by asm code */
- if (ea < (1UL << MAX_EA_BITS_PER_CONTEXT))
- goto slb_bad_addr;
+ if (unlikely(!(regs->msr & MSR_RI)))
+ return -EINVAL;
/*
- * consider this as bad access if we take a SLB miss
- * on an address above addr limit.
+ * SLB kernel faults must be very careful not to touch anything
+ * that is not bolted. E.g., PACA and global variables are okay,
+ * mm->context stuff is not.
+ *
+ * SLB user faults can access all of kernel memory, but must be
+ * careful not to touch things like IRQ state because it is not
+ * "reconciled" here. The difficulty is that we must use
+ * fast_exception_return to return from kernel SLB faults without
+ * looking at possible non-bolted memory. We could test user vs
+ * kernel faults in the interrupt handler asm and do a full fault,
+ * reconcile, ret_from_except for user faults which would make them
+ * first class kernel code. But for performance it's probably nicer
+ * if they go via fast_exception_return too.
*/
- if (ea >= current->mm->context.slb_addr_limit)
- goto slb_bad_addr;
+ if (id >= KERNEL_REGION_ID) {
+ return slb_allocate_kernel(ea, id);
+ } else {
+ struct mm_struct *mm = current->mm;
- context = get_ea_context(¤t->mm->context, ea);
- if (!context)
- goto slb_bad_addr;
+ if (unlikely(!mm))
+ return -EFAULT;
- handle_multi_context_slb_miss(context, ea);
- exception_exit(prev_state);
- return;
+ return slb_allocate_user(mm, ea);
+ }
+}
-slb_bad_addr:
- if (user_mode(regs))
- _exception(SIGSEGV, regs, SEGV_BNDERR, ea);
- else
- bad_page_fault(regs, ea, SIGSEGV);
- exception_exit(prev_state);
+void do_bad_slb_fault(struct pt_regs *regs, unsigned long ea, long err)
+{
+ if (err == -EFAULT) {
+ if (user_mode(regs))
+ _exception(SIGSEGV, regs, SEGV_BNDERR, ea);
+ else
+ bad_page_fault(regs, ea, SIGSEGV);
+ } else if (err == -EINVAL) {
+ unrecoverable_exception(regs);
+ } else {
+ BUG();
+ }
}
+++ /dev/null
-/*
- * Low-level SLB routines
- *
- * Copyright (C) 2004 David Gibson <dwg@au.ibm.com>, IBM
- *
- * Based on earlier C version:
- * Dave Engebretsen and Mike Corrigan {engebret|mikejc}@us.ibm.com
- * Copyright (c) 2001 Dave Engebretsen
- * Copyright (C) 2002 Anton Blanchard <anton@au.ibm.com>, IBM
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- */
-
-#include <asm/processor.h>
-#include <asm/ppc_asm.h>
-#include <asm/asm-offsets.h>
-#include <asm/cputable.h>
-#include <asm/page.h>
-#include <asm/mmu.h>
-#include <asm/pgtable.h>
-#include <asm/firmware.h>
-#include <asm/feature-fixups.h>
-
-/*
- * This macro generates asm code to compute the VSID scramble
- * function. Used in slb_allocate() and do_stab_bolted. The function
- * computed is: (protovsid*VSID_MULTIPLIER) % VSID_MODULUS
- *
- * rt = register containing the proto-VSID and into which the
- * VSID will be stored
- * rx = scratch register (clobbered)
- * rf = flags
- *
- * - rt and rx must be different registers
- * - The answer will end up in the low VSID_BITS bits of rt. The higher
- * bits may contain other garbage, so you may need to mask the
- * result.
- */
-#define ASM_VSID_SCRAMBLE(rt, rx, rf, size) \
- lis rx,VSID_MULTIPLIER_##size@h; \
- ori rx,rx,VSID_MULTIPLIER_##size@l; \
- mulld rt,rt,rx; /* rt = rt * MULTIPLIER */ \
-/* \
- * powermac get slb fault before feature fixup, so make 65 bit part \
- * the default part of feature fixup \
- */ \
-BEGIN_MMU_FTR_SECTION \
- srdi rx,rt,VSID_BITS_65_##size; \
- clrldi rt,rt,(64-VSID_BITS_65_##size); \
- add rt,rt,rx; \
- addi rx,rt,1; \
- srdi rx,rx,VSID_BITS_65_##size; \
- add rt,rt,rx; \
- rldimi rf,rt,SLB_VSID_SHIFT_##size,(64 - (SLB_VSID_SHIFT_##size + VSID_BITS_65_##size)); \
-MMU_FTR_SECTION_ELSE \
- srdi rx,rt,VSID_BITS_##size; \
- clrldi rt,rt,(64-VSID_BITS_##size); \
- add rt,rt,rx; /* add high and low bits */ \
- addi rx,rt,1; \
- srdi rx,rx,VSID_BITS_##size; /* extract 2^VSID_BITS bit */ \
- add rt,rt,rx; \
- rldimi rf,rt,SLB_VSID_SHIFT_##size,(64 - (SLB_VSID_SHIFT_##size + VSID_BITS_##size)); \
-ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_68_BIT_VA)
-
-
-/* void slb_allocate(unsigned long ea);
- *
- * Create an SLB entry for the given EA (user or kernel).
- * r3 = faulting address, r13 = PACA
- * r9, r10, r11 are clobbered by this function
- * r3 is preserved.
- * No other registers are examined or changed.
- */
-_GLOBAL(slb_allocate)
- /*
- * Check if the address falls within the range of the first context, or
- * if we may need to handle multi context. For the first context we
- * allocate the slb entry via the fast path below. For large address we
- * branch out to C-code and see if additional contexts have been
- * allocated.
- * The test here is:
- * (ea & ~REGION_MASK) >= (1ull << MAX_EA_BITS_PER_CONTEXT)
- */
- rldicr. r9,r3,4,(63 - MAX_EA_BITS_PER_CONTEXT - 4)
- bne- 8f
-
- srdi r9,r3,60 /* get region */
- srdi r10,r3,SID_SHIFT /* get esid */
- cmpldi cr7,r9,0xc /* cmp PAGE_OFFSET for later use */
-
- /* r3 = address, r10 = esid, cr7 = <> PAGE_OFFSET */
- blt cr7,0f /* user or kernel? */
-
- /* Check if hitting the linear mapping or some other kernel space
- */
- bne cr7,1f
-
- /* Linear mapping encoding bits, the "li" instruction below will
- * be patched by the kernel at boot
- */
-.globl slb_miss_kernel_load_linear
-slb_miss_kernel_load_linear:
- li r11,0
- /*
- * context = (ea >> 60) - (0xc - 1)
- * r9 = region id.
- */
- subi r9,r9,KERNEL_REGION_CONTEXT_OFFSET
-
-BEGIN_FTR_SECTION
- b .Lslb_finish_load
-END_MMU_FTR_SECTION_IFCLR(MMU_FTR_1T_SEGMENT)
- b .Lslb_finish_load_1T
-
-1:
-#ifdef CONFIG_SPARSEMEM_VMEMMAP
- cmpldi cr0,r9,0xf
- bne 1f
-/* Check virtual memmap region. To be patched at kernel boot */
-.globl slb_miss_kernel_load_vmemmap
-slb_miss_kernel_load_vmemmap:
- li r11,0
- b 6f
-1:
-#endif /* CONFIG_SPARSEMEM_VMEMMAP */
-
- /*
- * r10 contains the ESID, which is the original faulting EA shifted
- * right by 28 bits. We need to compare that with (H_VMALLOC_END >> 28)
- * which is 0xd00038000. That can't be used as an immediate, even if we
- * ignored the 0xd, so we have to load it into a register, and we only
- * have one register free. So we must load all of (H_VMALLOC_END >> 28)
- * into a register and compare ESID against that.
- */
- lis r11,(H_VMALLOC_END >> 32)@h // r11 = 0xffffffffd0000000
- ori r11,r11,(H_VMALLOC_END >> 32)@l // r11 = 0xffffffffd0003800
- // Rotate left 4, then mask with 0xffffffff0
- rldic r11,r11,4,28 // r11 = 0xd00038000
- cmpld r10,r11 // if r10 >= r11
- bge 5f // goto io_mapping
-
- /*
- * vmalloc mapping gets the encoding from the PACA as the mapping
- * can be demoted from 64K -> 4K dynamically on some machines.
- */
- lhz r11,PACAVMALLOCSLLP(r13)
- b 6f
-5:
- /* IO mapping */
-.globl slb_miss_kernel_load_io
-slb_miss_kernel_load_io:
- li r11,0
-6:
- /*
- * context = (ea >> 60) - (0xc - 1)
- * r9 = region id.
- */
- subi r9,r9,KERNEL_REGION_CONTEXT_OFFSET
-
-BEGIN_FTR_SECTION
- b .Lslb_finish_load
-END_MMU_FTR_SECTION_IFCLR(MMU_FTR_1T_SEGMENT)
- b .Lslb_finish_load_1T
-
-0: /*
- * For userspace addresses, make sure this is region 0.
- */
- cmpdi r9, 0
- bne- 8f
- /*
- * user space make sure we are within the allowed limit
- */
- ld r11,PACA_SLB_ADDR_LIMIT(r13)
- cmpld r3,r11
- bge- 8f
-
- /* when using slices, we extract the psize off the slice bitmaps
- * and then we need to get the sllp encoding off the mmu_psize_defs
- * array.
- *
- * XXX This is a bit inefficient especially for the normal case,
- * so we should try to implement a fast path for the standard page
- * size using the old sllp value so we avoid the array. We cannot
- * really do dynamic patching unfortunately as processes might flip
- * between 4k and 64k standard page size
- */
-#ifdef CONFIG_PPC_MM_SLICES
- /* r10 have esid */
- cmpldi r10,16
- /* below SLICE_LOW_TOP */
- blt 5f
- /*
- * Handle hpsizes,
- * r9 is get_paca()->context.high_slices_psize[index], r11 is mask_index
- */
- srdi r11,r10,(SLICE_HIGH_SHIFT - SLICE_LOW_SHIFT + 1) /* index */
- addi r9,r11,PACAHIGHSLICEPSIZE
- lbzx r9,r13,r9 /* r9 is hpsizes[r11] */
- /* r11 = (r10 >> (SLICE_HIGH_SHIFT - SLICE_LOW_SHIFT)) & 0x1 */
- rldicl r11,r10,(64 - (SLICE_HIGH_SHIFT - SLICE_LOW_SHIFT)),63
- b 6f
-
-5:
- /*
- * Handle lpsizes
- * r9 is get_paca()->context.low_slices_psize[index], r11 is mask_index
- */
- srdi r11,r10,1 /* index */
- addi r9,r11,PACALOWSLICESPSIZE
- lbzx r9,r13,r9 /* r9 is lpsizes[r11] */
- rldicl r11,r10,0,63 /* r11 = r10 & 0x1 */
-6:
- sldi r11,r11,2 /* index * 4 */
- /* Extract the psize and multiply to get an array offset */
- srd r9,r9,r11
- andi. r9,r9,0xf
- mulli r9,r9,MMUPSIZEDEFSIZE
-
- /* Now get to the array and obtain the sllp
- */
- ld r11,PACATOC(r13)
- ld r11,mmu_psize_defs@got(r11)
- add r11,r11,r9
- ld r11,MMUPSIZESLLP(r11)
- ori r11,r11,SLB_VSID_USER
-#else
- /* paca context sllp already contains the SLB_VSID_USER bits */
- lhz r11,PACACONTEXTSLLP(r13)
-#endif /* CONFIG_PPC_MM_SLICES */
-
- ld r9,PACACONTEXTID(r13)
-BEGIN_FTR_SECTION
- cmpldi r10,0x1000
- bge .Lslb_finish_load_1T
-END_MMU_FTR_SECTION_IFSET(MMU_FTR_1T_SEGMENT)
- b .Lslb_finish_load
-
-8: /* invalid EA - return an error indication */
- crset 4*cr0+eq /* indicate failure */
- blr
-
-/*
- * Finish loading of an SLB entry and return
- *
- * r3 = EA, r9 = context, r10 = ESID, r11 = flags, clobbers r9, cr7 = <> PAGE_OFFSET
- */
-.Lslb_finish_load:
- rldimi r10,r9,ESID_BITS,0
- ASM_VSID_SCRAMBLE(r10,r9,r11,256M)
- /* r3 = EA, r11 = VSID data */
- /*
- * Find a slot, round robin. Previously we tried to find a
- * free slot first but that took too long. Unfortunately we
- * dont have any LRU information to help us choose a slot.
- */
-
- mr r9,r3
-
- /* slb_finish_load_1T continues here. r9=EA with non-ESID bits clear */
-7: ld r10,PACASTABRR(r13)
- addi r10,r10,1
- /* This gets soft patched on boot. */
-.globl slb_compare_rr_to_size
-slb_compare_rr_to_size:
- cmpldi r10,0
-
- blt+ 4f
- li r10,SLB_NUM_BOLTED
-
-4:
- std r10,PACASTABRR(r13)
-
-3:
- rldimi r9,r10,0,36 /* r9 = EA[0:35] | entry */
- oris r10,r9,SLB_ESID_V@h /* r10 = r9 | SLB_ESID_V */
-
- /* r9 = ESID data, r11 = VSID data */
-
- /*
- * No need for an isync before or after this slbmte. The exception
- * we enter with and the rfid we exit with are context synchronizing.
- */
- slbmte r11,r10
-
- /* we're done for kernel addresses */
- crclr 4*cr0+eq /* set result to "success" */
- bgelr cr7
-
- /* Update the slb cache */
- lhz r9,PACASLBCACHEPTR(r13) /* offset = paca->slb_cache_ptr */
- cmpldi r9,SLB_CACHE_ENTRIES
- bge 1f
-
- /* still room in the slb cache */
- sldi r11,r9,2 /* r11 = offset * sizeof(u32) */
- srdi r10,r10,28 /* get the 36 bits of the ESID */
- add r11,r11,r13 /* r11 = (u32 *)paca + offset */
- stw r10,PACASLBCACHE(r11) /* paca->slb_cache[offset] = esid */
- addi r9,r9,1 /* offset++ */
- b 2f
-1: /* offset >= SLB_CACHE_ENTRIES */
- li r9,SLB_CACHE_ENTRIES+1
-2:
- sth r9,PACASLBCACHEPTR(r13) /* paca->slb_cache_ptr = offset */
- crclr 4*cr0+eq /* set result to "success" */
- blr
-
-/*
- * Finish loading of a 1T SLB entry (for the kernel linear mapping) and return.
- *
- * r3 = EA, r9 = context, r10 = ESID(256MB), r11 = flags, clobbers r9
- */
-.Lslb_finish_load_1T:
- srdi r10,r10,(SID_SHIFT_1T - SID_SHIFT) /* get 1T ESID */
- rldimi r10,r9,ESID_BITS_1T,0
- ASM_VSID_SCRAMBLE(r10,r9,r11,1T)
-
- li r10,MMU_SEGSIZE_1T
- rldimi r11,r10,SLB_VSID_SSIZE_SHIFT,0 /* insert segment size */
-
- /* r3 = EA, r11 = VSID data */
- clrrdi r9,r3,SID_SHIFT_1T /* clear out non-ESID bits */
- b 7b
-
-
-_ASM_NOKPROBE_SYMBOL(slb_allocate)
-_ASM_NOKPROBE_SYMBOL(slb_miss_kernel_load_linear)
-_ASM_NOKPROBE_SYMBOL(slb_miss_kernel_load_io)
-_ASM_NOKPROBE_SYMBOL(slb_compare_rr_to_size)
-#ifdef CONFIG_SPARSEMEM_VMEMMAP
-_ASM_NOKPROBE_SYMBOL(slb_miss_kernel_load_vmemmap)
-#endif
git.samba.org / sfrench / cifs-2.6.git / commitdiff