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Diffstat (limited to 'arch/powerpc/mm/slb.c')
-rw-r--r--arch/powerpc/mm/slb.c162
1 files changed, 93 insertions, 69 deletions
diff --git a/arch/powerpc/mm/slb.c b/arch/powerpc/mm/slb.c
index 906daeda59a..0399a670295 100644
--- a/arch/powerpc/mm/slb.c
+++ b/arch/powerpc/mm/slb.c
@@ -2,7 +2,7 @@
* PowerPC64 SLB support.
*
* Copyright (C) 2004 David Gibson <dwg@au.ibm.com>, IBM
- * Based on earlier code writteh by:
+ * Based on earlier code written by:
* 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
@@ -14,8 +14,6 @@
* 2 of the License, or (at your option) any later version.
*/
-#undef DEBUG
-
#include <asm/pgtable.h>
#include <asm/mmu.h>
#include <asm/mmu_context.h>
@@ -23,15 +21,10 @@
#include <asm/cputable.h>
#include <asm/cacheflush.h>
#include <asm/smp.h>
-#include <asm/firmware.h>
#include <linux/compiler.h>
#include <asm/udbg.h>
+#include <asm/code-patching.h>
-#ifdef DEBUG
-#define DBG(fmt...) udbg_printf(fmt)
-#else
-#define DBG(fmt...)
-#endif
extern void slb_allocate_realmode(unsigned long ea);
extern void slb_allocate_user(unsigned long ea);
@@ -44,13 +37,13 @@ static void slb_allocate(unsigned long ea)
slb_allocate_realmode(ea);
}
+#define slb_esid_mask(ssize) \
+ (((ssize) == MMU_SEGSIZE_256M)? ESID_MASK: ESID_MASK_1T)
+
static inline unsigned long mk_esid_data(unsigned long ea, int ssize,
unsigned long slot)
{
- unsigned long mask;
-
- mask = (ssize == MMU_SEGSIZE_256M)? ESID_MASK: ESID_MASK_1T;
- return (ea & mask) | SLB_ESID_V | slot;
+ return (ea & slb_esid_mask(ssize)) | SLB_ESID_V | slot;
}
#define slb_vsid_shift(ssize) \
@@ -73,8 +66,10 @@ static inline void slb_shadow_update(unsigned long ea, int ssize,
* we only update the current CPU's SLB shadow buffer.
*/
get_slb_shadow()->save_area[entry].esid = 0;
- get_slb_shadow()->save_area[entry].vsid = mk_vsid_data(ea, ssize, flags);
- get_slb_shadow()->save_area[entry].esid = mk_esid_data(ea, ssize, entry);
+ get_slb_shadow()->save_area[entry].vsid =
+ cpu_to_be64(mk_vsid_data(ea, ssize, flags));
+ get_slb_shadow()->save_area[entry].esid =
+ cpu_to_be64(mk_esid_data(ea, ssize, entry));
}
static inline void slb_shadow_clear(unsigned long entry)
@@ -99,15 +94,13 @@ static inline void create_shadowed_slbe(unsigned long ea, int ssize,
: "memory" );
}
-void slb_flush_and_rebolt(void)
+static void __slb_flush_and_rebolt(void)
{
/* If you change this make sure you change SLB_NUM_BOLTED
- * appropriately too. */
+ * and PR KVM appropriately too. */
unsigned long linear_llp, vmalloc_llp, lflags, vflags;
unsigned long ksp_esid_data, ksp_vsid_data;
- WARN_ON(!irqs_disabled());
-
linear_llp = mmu_psize_defs[mmu_linear_psize].sllp;
vmalloc_llp = mmu_psize_defs[mmu_vmalloc_psize].sllp;
lflags = SLB_VSID_KERNEL | linear_llp;
@@ -121,15 +114,10 @@ void slb_flush_and_rebolt(void)
} else {
/* Update stack entry; others don't change */
slb_shadow_update(get_paca()->kstack, mmu_kernel_ssize, lflags, 2);
- ksp_vsid_data = get_slb_shadow()->save_area[2].vsid;
+ ksp_vsid_data =
+ be64_to_cpu(get_slb_shadow()->save_area[2].vsid);
}
- /*
- * We can't take a PMU exception in the following code, so hard
- * disable interrupts.
- */
- hard_irq_disable();
-
/* We need to do this all in asm, so we're sure we don't touch
* the stack between the slbia and rebolting it. */
asm volatile("isync\n"
@@ -146,6 +134,21 @@ void slb_flush_and_rebolt(void)
: "memory");
}
+void slb_flush_and_rebolt(void)
+{
+
+ WARN_ON(!irqs_disabled());
+
+ /*
+ * We can't take a PMU exception in the following code, so hard
+ * disable interrupts.
+ */
+ hard_irq_disable();
+
+ __slb_flush_and_rebolt();
+ get_paca()->slb_cache_ptr = 0;
+}
+
void slb_vmalloc_update(void)
{
unsigned long vflags;
@@ -166,7 +169,7 @@ static inline int esids_match(unsigned long addr1, unsigned long addr2)
int esid_1t_count;
/* System is not 1T segment size capable. */
- if (!cpu_has_feature(CPU_FTR_1T_SEGMENT))
+ if (!mmu_has_feature(MMU_FTR_1T_SEGMENT))
return (GET_ESID(addr1) == GET_ESID(addr2));
esid_1t_count = (((addr1 >> SID_SHIFT_1T) != 0) +
@@ -187,13 +190,21 @@ static inline int esids_match(unsigned long addr1, unsigned long addr2)
/* Flush all user entries from the segment table of the current processor. */
void switch_slb(struct task_struct *tsk, struct mm_struct *mm)
{
- unsigned long offset = get_paca()->slb_cache_ptr;
+ unsigned long offset;
unsigned long slbie_data = 0;
unsigned long pc = KSTK_EIP(tsk);
unsigned long stack = KSTK_ESP(tsk);
- unsigned long unmapped_base;
+ unsigned long exec_base;
- if (!cpu_has_feature(CPU_FTR_NO_SLBIE_B) &&
+ /*
+ * We need interrupts hard-disabled here, not just soft-disabled,
+ * so that a PMU interrupt can't occur, which might try to access
+ * user memory (to get a stack trace) and possible cause an SLB miss
+ * which would update the slb_cache/slb_cache_ptr fields in the PACA.
+ */
+ hard_irq_disable();
+ offset = get_paca()->slb_cache_ptr;
+ if (!mmu_has_feature(MMU_FTR_NO_SLBIE_B) &&
offset <= SLB_CACHE_ENTRIES) {
int i;
asm volatile("isync" : : : "memory");
@@ -207,7 +218,7 @@ void switch_slb(struct task_struct *tsk, struct mm_struct *mm)
}
asm volatile("isync" : : : "memory");
} else {
- slb_flush_and_rebolt();
+ __slb_flush_and_rebolt();
}
/* Workaround POWER5 < DD2.1 issue */
@@ -219,40 +230,45 @@ void switch_slb(struct task_struct *tsk, struct mm_struct *mm)
/*
* preload some userspace segments into the SLB.
+ * Almost all 32 and 64bit PowerPC executables are linked at
+ * 0x10000000 so it makes sense to preload this segment.
*/
- if (test_tsk_thread_flag(tsk, TIF_32BIT))
- unmapped_base = TASK_UNMAPPED_BASE_USER32;
- else
- unmapped_base = TASK_UNMAPPED_BASE_USER64;
-
- if (is_kernel_addr(pc))
- return;
- slb_allocate(pc);
+ exec_base = 0x10000000;
- if (esids_match(pc,stack))
+ if (is_kernel_addr(pc) || is_kernel_addr(stack) ||
+ is_kernel_addr(exec_base))
return;
- if (is_kernel_addr(stack))
- return;
- slb_allocate(stack);
+ slb_allocate(pc);
- if (esids_match(pc,unmapped_base) || esids_match(stack,unmapped_base))
- return;
+ if (!esids_match(pc, stack))
+ slb_allocate(stack);
- if (is_kernel_addr(unmapped_base))
- return;
- slb_allocate(unmapped_base);
+ 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)
{
- /* Assume the instruction had a "0" immediate value, just
- * "or" in the new value
- */
- *insn_addr |= immed;
- flush_icache_range((unsigned long)insn_addr, 4+
- (unsigned long)insn_addr);
+ int insn = (*insn_addr & 0xffff0000) | immed;
+ patch_instruction(insn_addr, insn);
+}
+
+extern u32 slb_compare_rr_to_size[];
+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)
@@ -260,16 +276,18 @@ void slb_initialize(void)
unsigned long linear_llp, vmalloc_llp, io_llp;
unsigned long lflags, vflags;
static int slb_encoding_inited;
- extern unsigned int *slb_miss_kernel_load_linear;
- extern unsigned int *slb_miss_kernel_load_io;
- extern unsigned int *slb_compare_rr_to_size;
+#ifdef CONFIG_SPARSEMEM_VMEMMAP
+ unsigned long vmemmap_llp;
+#endif
/* Prepare our SLB miss handler based on our page size */
linear_llp = mmu_psize_defs[mmu_linear_psize].sllp;
io_llp = mmu_psize_defs[mmu_io_psize].sllp;
vmalloc_llp = mmu_psize_defs[mmu_vmalloc_psize].sllp;
get_paca()->vmalloc_sllp = SLB_VSID_KERNEL | vmalloc_llp;
-
+#ifdef CONFIG_SPARSEMEM_VMEMMAP
+ vmemmap_llp = mmu_psize_defs[mmu_vmemmap_psize].sllp;
+#endif
if (!slb_encoding_inited) {
slb_encoding_inited = 1;
patch_slb_encoding(slb_miss_kernel_load_linear,
@@ -279,17 +297,18 @@ void slb_initialize(void)
patch_slb_encoding(slb_compare_rr_to_size,
mmu_slb_size);
- DBG("SLB: linear LLP = %04x\n", linear_llp);
- DBG("SLB: io LLP = %04x\n", io_llp);
+ 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
}
get_paca()->stab_rr = SLB_NUM_BOLTED;
- /* On iSeries the bolted entries have already been set up by
- * the hypervisor from the lparMap data in head.S */
- if (firmware_has_feature(FW_FEATURE_ISERIES))
- return;
-
lflags = SLB_VSID_KERNEL | linear_llp;
vflags = SLB_VSID_KERNEL | vmalloc_llp;
@@ -301,11 +320,16 @@ void slb_initialize(void)
create_shadowed_slbe(VMALLOC_START, mmu_kernel_ssize, vflags, 1);
+ /* For the boot cpu, we're running on the stack in init_thread_union,
+ * which is in the first segment of the linear mapping, and also
+ * get_paca()->kstack hasn't been initialized yet.
+ * For secondary cpus, we need to bolt the kernel stack entry now.
+ */
slb_shadow_clear(2);
+ if (raw_smp_processor_id() != boot_cpuid &&
+ (get_paca()->kstack & slb_esid_mask(mmu_kernel_ssize)) > PAGE_OFFSET)
+ create_shadowed_slbe(get_paca()->kstack,
+ mmu_kernel_ssize, lflags, 2);
- /* We don't bolt the stack for the time being - we're in boot,
- * so the stack is in the bolted segment. By the time it goes
- * elsewhere, we'll call _switch() which will bolt in the new
- * one. */
asm volatile("isync":::"memory");
}