diff options
Diffstat (limited to 'arch/arm64/include/asm/tlbflush.h')
| -rw-r--r-- | arch/arm64/include/asm/tlbflush.h | 320 |
1 files changed, 290 insertions, 30 deletions
diff --git a/arch/arm64/include/asm/tlbflush.h b/arch/arm64/include/asm/tlbflush.h index bc3949064725..3b0e8248e1a4 100644 --- a/arch/arm64/include/asm/tlbflush.h +++ b/arch/arm64/include/asm/tlbflush.h @@ -10,8 +10,10 @@ #ifndef __ASSEMBLY__ +#include <linux/bitfield.h> #include <linux/mm_types.h> #include <linux/sched.h> +#include <linux/mmu_notifier.h> #include <asm/cputype.h> #include <asm/mmu.h> @@ -27,14 +29,16 @@ * not. The macros handles invoking the asm with or without the * register argument as appropriate. */ -#define __TLBI_0(op, arg) asm ("tlbi " #op "\n" \ +#define __TLBI_0(op, arg) asm (ARM64_ASM_PREAMBLE \ + "tlbi " #op "\n" \ ALTERNATIVE("nop\n nop", \ "dsb ish\n tlbi " #op, \ ARM64_WORKAROUND_REPEAT_TLBI, \ CONFIG_ARM64_WORKAROUND_REPEAT_TLBI) \ : : ) -#define __TLBI_1(op, arg) asm ("tlbi " #op ", %0\n" \ +#define __TLBI_1(op, arg) asm (ARM64_ASM_PREAMBLE \ + "tlbi " #op ", %0\n" \ ALTERNATIVE("nop\n nop", \ "dsb ish\n tlbi " #op ", %0", \ ARM64_WORKAROUND_REPEAT_TLBI, \ @@ -60,6 +64,111 @@ }) /* + * Get translation granule of the system, which is decided by + * PAGE_SIZE. Used by TTL. + * - 4KB : 1 + * - 16KB : 2 + * - 64KB : 3 + */ +#define TLBI_TTL_TG_4K 1 +#define TLBI_TTL_TG_16K 2 +#define TLBI_TTL_TG_64K 3 + +static inline unsigned long get_trans_granule(void) +{ + switch (PAGE_SIZE) { + case SZ_4K: + return TLBI_TTL_TG_4K; + case SZ_16K: + return TLBI_TTL_TG_16K; + case SZ_64K: + return TLBI_TTL_TG_64K; + default: + return 0; + } +} + +/* + * Level-based TLBI operations. + * + * When ARMv8.4-TTL exists, TLBI operations take an additional hint for + * the level at which the invalidation must take place. If the level is + * wrong, no invalidation may take place. In the case where the level + * cannot be easily determined, the value TLBI_TTL_UNKNOWN will perform + * a non-hinted invalidation. Any provided level outside the hint range + * will also cause fall-back to non-hinted invalidation. + * + * For Stage-2 invalidation, use the level values provided to that effect + * in asm/stage2_pgtable.h. + */ +#define TLBI_TTL_MASK GENMASK_ULL(47, 44) + +#define TLBI_TTL_UNKNOWN INT_MAX + +#define __tlbi_level(op, addr, level) do { \ + u64 arg = addr; \ + \ + if (alternative_has_cap_unlikely(ARM64_HAS_ARMv8_4_TTL) && \ + level >= 0 && level <= 3) { \ + u64 ttl = level & 3; \ + ttl |= get_trans_granule() << 2; \ + arg &= ~TLBI_TTL_MASK; \ + arg |= FIELD_PREP(TLBI_TTL_MASK, ttl); \ + } \ + \ + __tlbi(op, arg); \ +} while(0) + +#define __tlbi_user_level(op, arg, level) do { \ + if (arm64_kernel_unmapped_at_el0()) \ + __tlbi_level(op, (arg | USER_ASID_FLAG), level); \ +} while (0) + +/* + * This macro creates a properly formatted VA operand for the TLB RANGE. The + * value bit assignments are: + * + * +----------+------+-------+-------+-------+----------------------+ + * | ASID | TG | SCALE | NUM | TTL | BADDR | + * +-----------------+-------+-------+-------+----------------------+ + * |63 48|47 46|45 44|43 39|38 37|36 0| + * + * The address range is determined by below formula: [BADDR, BADDR + (NUM + 1) * + * 2^(5*SCALE + 1) * PAGESIZE) + * + * Note that the first argument, baddr, is pre-shifted; If LPA2 is in use, BADDR + * holds addr[52:16]. Else BADDR holds page number. See for example ARM DDI + * 0487J.a section C5.5.60 "TLBI VAE1IS, TLBI VAE1ISNXS, TLB Invalidate by VA, + * EL1, Inner Shareable". + * + */ +#define __TLBI_VADDR_RANGE(baddr, asid, scale, num, ttl) \ + ({ \ + unsigned long __ta = (baddr); \ + unsigned long __ttl = (ttl >= 1 && ttl <= 3) ? ttl : 0; \ + __ta &= GENMASK_ULL(36, 0); \ + __ta |= __ttl << 37; \ + __ta |= (unsigned long)(num) << 39; \ + __ta |= (unsigned long)(scale) << 44; \ + __ta |= get_trans_granule() << 46; \ + __ta |= (unsigned long)(asid) << 48; \ + __ta; \ + }) + +/* These macros are used by the TLBI RANGE feature. */ +#define __TLBI_RANGE_PAGES(num, scale) \ + ((unsigned long)((num) + 1) << (5 * (scale) + 1)) +#define MAX_TLBI_RANGE_PAGES __TLBI_RANGE_PAGES(31, 3) + +/* + * Generate 'num' values from -1 to 30 with -1 rejected by the + * __flush_tlb_range() loop below. + */ +#define TLBI_RANGE_MASK GENMASK_ULL(4, 0) +#define __TLBI_RANGE_NUM(pages, scale) \ + ((((pages) >> (5 * (scale) + 1)) & TLBI_RANGE_MASK) - 1) + +/* * TLB Invalidation * ================ * @@ -116,12 +225,16 @@ * CPUs, ensuring that any walk-cache entries associated with the * translation are also invalidated. * - * __flush_tlb_range(vma, start, end, stride, last_level) + * __flush_tlb_range(vma, start, end, stride, last_level, tlb_level) * Invalidate the virtual-address range '[start, end)' on all * CPUs for the user address space corresponding to 'vma->mm'. * The invalidation operations are issued at a granularity * determined by 'stride' and only affect any walk-cache entries - * if 'last_level' is equal to false. + * if 'last_level' is equal to false. tlb_level is the level at + * which the invalidation must take place. If the level is wrong, + * no invalidation may take place. In the case where the level + * cannot be easily determined, the value TLBI_TTL_UNKNOWN will + * perform a non-hinted invalidation. * * * Finally, take a look at asm/tlb.h to see how tlb_flush() is implemented @@ -146,22 +259,33 @@ static inline void flush_tlb_all(void) static inline void flush_tlb_mm(struct mm_struct *mm) { - unsigned long asid = __TLBI_VADDR(0, ASID(mm)); + unsigned long asid; dsb(ishst); + asid = __TLBI_VADDR(0, ASID(mm)); __tlbi(aside1is, asid); __tlbi_user(aside1is, asid); dsb(ish); + mmu_notifier_arch_invalidate_secondary_tlbs(mm, 0, -1UL); } -static inline void flush_tlb_page_nosync(struct vm_area_struct *vma, - unsigned long uaddr) +static inline void __flush_tlb_page_nosync(struct mm_struct *mm, + unsigned long uaddr) { - unsigned long addr = __TLBI_VADDR(uaddr, ASID(vma->vm_mm)); + unsigned long addr; dsb(ishst); + addr = __TLBI_VADDR(uaddr, ASID(mm)); __tlbi(vale1is, addr); __tlbi_user(vale1is, addr); + mmu_notifier_arch_invalidate_secondary_tlbs(mm, uaddr & PAGE_MASK, + (uaddr & PAGE_MASK) + PAGE_SIZE); +} + +static inline void flush_tlb_page_nosync(struct vm_area_struct *vma, + unsigned long uaddr) +{ + return __flush_tlb_page_nosync(vma->vm_mm, uaddr); } static inline void flush_tlb_page(struct vm_area_struct *vma, @@ -171,43 +295,177 @@ static inline void flush_tlb_page(struct vm_area_struct *vma, dsb(ish); } +static inline bool arch_tlbbatch_should_defer(struct mm_struct *mm) +{ + /* + * TLB flush deferral is not required on systems which are affected by + * ARM64_WORKAROUND_REPEAT_TLBI, as __tlbi()/__tlbi_user() implementation + * will have two consecutive TLBI instructions with a dsb(ish) in between + * defeating the purpose (i.e save overall 'dsb ish' cost). + */ + if (alternative_has_cap_unlikely(ARM64_WORKAROUND_REPEAT_TLBI)) + return false; + + return true; +} + +static inline void arch_tlbbatch_add_pending(struct arch_tlbflush_unmap_batch *batch, + struct mm_struct *mm, + unsigned long uaddr) +{ + __flush_tlb_page_nosync(mm, uaddr); +} + +/* + * If mprotect/munmap/etc occurs during TLB batched flushing, we need to + * synchronise all the TLBI issued with a DSB to avoid the race mentioned in + * flush_tlb_batched_pending(). + */ +static inline void arch_flush_tlb_batched_pending(struct mm_struct *mm) +{ + dsb(ish); +} + +/* + * To support TLB batched flush for multiple pages unmapping, we only send + * the TLBI for each page in arch_tlbbatch_add_pending() and wait for the + * completion at the end in arch_tlbbatch_flush(). Since we've already issued + * TLBI for each page so only a DSB is needed to synchronise its effect on the + * other CPUs. + * + * This will save the time waiting on DSB comparing issuing a TLBI;DSB sequence + * for each page. + */ +static inline void arch_tlbbatch_flush(struct arch_tlbflush_unmap_batch *batch) +{ + dsb(ish); +} + /* * This is meant to avoid soft lock-ups on large TLB flushing ranges and not * necessarily a performance improvement. */ -#define MAX_TLBI_OPS PTRS_PER_PTE +#define MAX_DVM_OPS PTRS_PER_PTE -static inline void __flush_tlb_range(struct vm_area_struct *vma, +/* + * __flush_tlb_range_op - Perform TLBI operation upon a range + * + * @op: TLBI instruction that operates on a range (has 'r' prefix) + * @start: The start address of the range + * @pages: Range as the number of pages from 'start' + * @stride: Flush granularity + * @asid: The ASID of the task (0 for IPA instructions) + * @tlb_level: Translation Table level hint, if known + * @tlbi_user: If 'true', call an additional __tlbi_user() + * (typically for user ASIDs). 'flase' for IPA instructions + * @lpa2: If 'true', the lpa2 scheme is used as set out below + * + * When the CPU does not support TLB range operations, flush the TLB + * entries one by one at the granularity of 'stride'. If the TLB + * range ops are supported, then: + * + * 1. If FEAT_LPA2 is in use, the start address of a range operation must be + * 64KB aligned, so flush pages one by one until the alignment is reached + * using the non-range operations. This step is skipped if LPA2 is not in + * use. + * + * 2. The minimum range granularity is decided by 'scale', so multiple range + * TLBI operations may be required. Start from scale = 3, flush the largest + * possible number of pages ((num+1)*2^(5*scale+1)) that fit into the + * requested range, then decrement scale and continue until one or zero pages + * are left. We must start from highest scale to ensure 64KB start alignment + * is maintained in the LPA2 case. + * + * 3. If there is 1 page remaining, flush it through non-range operations. Range + * operations can only span an even number of pages. We save this for last to + * ensure 64KB start alignment is maintained for the LPA2 case. + * + * Note that certain ranges can be represented by either num = 31 and + * scale or num = 0 and scale + 1. The loop below favours the latter + * since num is limited to 30 by the __TLBI_RANGE_NUM() macro. + */ +#define __flush_tlb_range_op(op, start, pages, stride, \ + asid, tlb_level, tlbi_user, lpa2) \ +do { \ + int num = 0; \ + int scale = 3; \ + int shift = lpa2 ? 16 : PAGE_SHIFT; \ + unsigned long addr; \ + \ + while (pages > 0) { \ + if (!system_supports_tlb_range() || \ + pages == 1 || \ + (lpa2 && start != ALIGN(start, SZ_64K))) { \ + addr = __TLBI_VADDR(start, asid); \ + __tlbi_level(op, addr, tlb_level); \ + if (tlbi_user) \ + __tlbi_user_level(op, addr, tlb_level); \ + start += stride; \ + pages -= stride >> PAGE_SHIFT; \ + continue; \ + } \ + \ + num = __TLBI_RANGE_NUM(pages, scale); \ + if (num >= 0) { \ + addr = __TLBI_VADDR_RANGE(start >> shift, asid, \ + scale, num, tlb_level); \ + __tlbi(r##op, addr); \ + if (tlbi_user) \ + __tlbi_user(r##op, addr); \ + start += __TLBI_RANGE_PAGES(num, scale) << PAGE_SHIFT; \ + pages -= __TLBI_RANGE_PAGES(num, scale); \ + } \ + scale--; \ + } \ +} while (0) + +#define __flush_s2_tlb_range_op(op, start, pages, stride, tlb_level) \ + __flush_tlb_range_op(op, start, pages, stride, 0, tlb_level, false, kvm_lpa2_is_enabled()); + +static inline void __flush_tlb_range_nosync(struct vm_area_struct *vma, unsigned long start, unsigned long end, - unsigned long stride, bool last_level) + unsigned long stride, bool last_level, + int tlb_level) { - unsigned long asid = ASID(vma->vm_mm); - unsigned long addr; + unsigned long asid, pages; start = round_down(start, stride); end = round_up(end, stride); + pages = (end - start) >> PAGE_SHIFT; - if ((end - start) >= (MAX_TLBI_OPS * stride)) { + /* + * When not uses TLB range ops, we can handle up to + * (MAX_DVM_OPS - 1) pages; + * When uses TLB range ops, we can handle up to + * (MAX_TLBI_RANGE_PAGES - 1) pages. + */ + if ((!system_supports_tlb_range() && + (end - start) >= (MAX_DVM_OPS * stride)) || + pages >= MAX_TLBI_RANGE_PAGES) { flush_tlb_mm(vma->vm_mm); return; } - /* Convert the stride into units of 4k */ - stride >>= 12; + dsb(ishst); + asid = ASID(vma->vm_mm); - start = __TLBI_VADDR(start, asid); - end = __TLBI_VADDR(end, asid); + if (last_level) + __flush_tlb_range_op(vale1is, start, pages, stride, asid, + tlb_level, true, lpa2_is_enabled()); + else + __flush_tlb_range_op(vae1is, start, pages, stride, asid, + tlb_level, true, lpa2_is_enabled()); - dsb(ishst); - for (addr = start; addr < end; addr += stride) { - if (last_level) { - __tlbi(vale1is, addr); - __tlbi_user(vale1is, addr); - } else { - __tlbi(vae1is, addr); - __tlbi_user(vae1is, addr); - } - } + mmu_notifier_arch_invalidate_secondary_tlbs(vma->vm_mm, start, end); +} + +static inline void __flush_tlb_range(struct vm_area_struct *vma, + unsigned long start, unsigned long end, + unsigned long stride, bool last_level, + int tlb_level) +{ + __flush_tlb_range_nosync(vma, start, end, stride, + last_level, tlb_level); dsb(ish); } @@ -217,15 +475,17 @@ static inline void flush_tlb_range(struct vm_area_struct *vma, /* * We cannot use leaf-only invalidation here, since we may be invalidating * table entries as part of collapsing hugepages or moving page tables. + * Set the tlb_level to TLBI_TTL_UNKNOWN because we can not get enough + * information here. */ - __flush_tlb_range(vma, start, end, PAGE_SIZE, false); + __flush_tlb_range(vma, start, end, PAGE_SIZE, false, TLBI_TTL_UNKNOWN); } static inline void flush_tlb_kernel_range(unsigned long start, unsigned long end) { unsigned long addr; - if ((end - start) > (MAX_TLBI_OPS * PAGE_SIZE)) { + if ((end - start) > (MAX_DVM_OPS * PAGE_SIZE)) { flush_tlb_all(); return; } |