--- zzzz-none-000/linux-3.10.107/arch/powerpc/mm/slb.c 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/arch/powerpc/mm/slb.c 2021-02-04 17:41:59.000000000 +0000 @@ -25,6 +25,11 @@ #include #include +enum slb_index { + LINEAR_INDEX = 0, /* Kernel linear map (0xc000000000000000) */ + VMALLOC_INDEX = 1, /* Kernel virtual map (0xd000000000000000) */ + KSTACK_INDEX = 2, /* Kernel stack map */ +}; extern void slb_allocate_realmode(unsigned long ea); extern void slb_allocate_user(unsigned long ea); @@ -41,14 +46,11 @@ (((ssize) == MMU_SEGSIZE_256M)? ESID_MASK: ESID_MASK_1T) static inline unsigned long mk_esid_data(unsigned long ea, int ssize, - unsigned long slot) + enum slb_index index) { - return (ea & slb_esid_mask(ssize)) | SLB_ESID_V | slot; + return (ea & slb_esid_mask(ssize)) | SLB_ESID_V | index; } -#define slb_vsid_shift(ssize) \ - ((ssize) == MMU_SEGSIZE_256M? SLB_VSID_SHIFT: SLB_VSID_SHIFT_1T) - static inline unsigned long mk_vsid_data(unsigned long ea, int ssize, unsigned long flags) { @@ -58,44 +60,46 @@ static inline void slb_shadow_update(unsigned long ea, int ssize, unsigned long flags, - unsigned long entry) + enum slb_index index) { + struct slb_shadow *p = get_slb_shadow(); + /* * Clear the ESID first so the entry is not valid while we are * updating it. No write barriers are needed here, provided * 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); + p->save_area[index].esid = 0; + p->save_area[index].vsid = cpu_to_be64(mk_vsid_data(ea, ssize, flags)); + p->save_area[index].esid = cpu_to_be64(mk_esid_data(ea, ssize, index)); } -static inline void slb_shadow_clear(unsigned long entry) +static inline void slb_shadow_clear(enum slb_index index) { - get_slb_shadow()->save_area[entry].esid = 0; + get_slb_shadow()->save_area[index].esid = 0; } static inline void create_shadowed_slbe(unsigned long ea, int ssize, unsigned long flags, - unsigned long entry) + enum slb_index index) { /* * Updating the shadow buffer before writing the SLB ensures * we don't get a stale entry here if we get preempted by PHYP * between these two statements. */ - slb_shadow_update(ea, ssize, flags, entry); + slb_shadow_update(ea, ssize, flags, index); asm volatile("slbmte %0,%1" : : "r" (mk_vsid_data(ea, ssize, flags)), - "r" (mk_esid_data(ea, ssize, entry)) + "r" (mk_esid_data(ea, ssize, index)) : "memory" ); } 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; @@ -104,15 +108,16 @@ lflags = SLB_VSID_KERNEL | linear_llp; vflags = SLB_VSID_KERNEL | vmalloc_llp; - ksp_esid_data = mk_esid_data(get_paca()->kstack, mmu_kernel_ssize, 2); + ksp_esid_data = mk_esid_data(get_paca()->kstack, mmu_kernel_ssize, KSTACK_INDEX); if ((ksp_esid_data & ~0xfffffffUL) <= PAGE_OFFSET) { ksp_esid_data &= ~SLB_ESID_V; ksp_vsid_data = 0; - slb_shadow_clear(2); + slb_shadow_clear(KSTACK_INDEX); } 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; + slb_shadow_update(get_paca()->kstack, mmu_kernel_ssize, lflags, KSTACK_INDEX); + ksp_vsid_data = + be64_to_cpu(get_slb_shadow()->save_area[KSTACK_INDEX].vsid); } /* We need to do this all in asm, so we're sure we don't touch @@ -151,7 +156,7 @@ unsigned long vflags; vflags = SLB_VSID_KERNEL | mmu_psize_defs[mmu_vmalloc_psize].sllp; - slb_shadow_update(VMALLOC_START, mmu_kernel_ssize, vflags, 1); + slb_shadow_update(VMALLOC_START, mmu_kernel_ssize, vflags, VMALLOC_INDEX); slb_flush_and_rebolt(); } @@ -249,14 +254,31 @@ static inline void patch_slb_encoding(unsigned int *insn_addr, unsigned int immed) { - int insn = (*insn_addr & 0xffff0000) | 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); } +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) { - extern unsigned int *slb_compare_rr_to_size; - if (mmu_slb_size == size) return; @@ -269,11 +291,7 @@ 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 - extern unsigned int *slb_miss_kernel_load_vmemmap; unsigned long vmemmap_llp; #endif @@ -309,24 +327,23 @@ lflags = SLB_VSID_KERNEL | linear_llp; vflags = SLB_VSID_KERNEL | vmalloc_llp; - /* Invalidate the entire SLB (even slot 0) & all the ERATS */ + /* Invalidate the entire SLB (even entry 0) & all the ERATS */ asm volatile("isync":::"memory"); asm volatile("slbmte %0,%0"::"r" (0) : "memory"); asm volatile("isync; slbia; isync":::"memory"); - create_shadowed_slbe(PAGE_OFFSET, mmu_kernel_ssize, lflags, 0); - - create_shadowed_slbe(VMALLOC_START, mmu_kernel_ssize, vflags, 1); + create_shadowed_slbe(PAGE_OFFSET, mmu_kernel_ssize, lflags, LINEAR_INDEX); + create_shadowed_slbe(VMALLOC_START, mmu_kernel_ssize, vflags, VMALLOC_INDEX); /* 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); + slb_shadow_clear(KSTACK_INDEX); 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); + mmu_kernel_ssize, lflags, KSTACK_INDEX); asm volatile("isync":::"memory"); }