diff options
Diffstat (limited to 'arch/frv/mm/mmu-context.c')
| -rw-r--r-- | arch/frv/mm/mmu-context.c | 210 |
1 files changed, 0 insertions, 210 deletions
diff --git a/arch/frv/mm/mmu-context.c b/arch/frv/mm/mmu-context.c deleted file mode 100644 index 16946a58f64d..000000000000 --- a/arch/frv/mm/mmu-context.c +++ /dev/null @@ -1,210 +0,0 @@ -/* mmu-context.c: MMU context allocation and management - * - * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. - * Written by David Howells (dhowells@redhat.com) - * - * 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 <linux/sched.h> -#include <linux/sched/mm.h> -#include <linux/sched/task.h> -#include <linux/mm.h> -#include <asm/tlbflush.h> - -#define NR_CXN 4096 - -static unsigned long cxn_bitmap[NR_CXN / (sizeof(unsigned long) * 8)]; -static LIST_HEAD(cxn_owners_lru); -static DEFINE_SPINLOCK(cxn_owners_lock); - -int __nongpreldata cxn_pinned = -1; - - -/*****************************************************************************/ -/* - * initialise a new context - */ -int init_new_context(struct task_struct *tsk, struct mm_struct *mm) -{ - memset(&mm->context, 0, sizeof(mm->context)); - INIT_LIST_HEAD(&mm->context.id_link); - mm->context.itlb_cached_pge = 0xffffffffUL; - mm->context.dtlb_cached_pge = 0xffffffffUL; - - return 0; -} /* end init_new_context() */ - -/*****************************************************************************/ -/* - * make sure a kernel MMU context has a CPU context number - * - call with cxn_owners_lock held - */ -static unsigned get_cxn(mm_context_t *ctx) -{ - struct list_head *_p; - mm_context_t *p; - unsigned cxn; - - if (!list_empty(&ctx->id_link)) { - list_move_tail(&ctx->id_link, &cxn_owners_lru); - } - else { - /* find the first unallocated context number - * - 0 is reserved for the kernel - */ - cxn = find_next_zero_bit(cxn_bitmap, NR_CXN, 1); - if (cxn < NR_CXN) { - set_bit(cxn, cxn_bitmap); - } - else { - /* none remaining - need to steal someone else's cxn */ - p = NULL; - list_for_each(_p, &cxn_owners_lru) { - p = list_entry(_p, mm_context_t, id_link); - if (!p->id_busy && p->id != cxn_pinned) - break; - } - - BUG_ON(_p == &cxn_owners_lru); - - cxn = p->id; - p->id = 0; - list_del_init(&p->id_link); - __flush_tlb_mm(cxn); - } - - ctx->id = cxn; - list_add_tail(&ctx->id_link, &cxn_owners_lru); - } - - return ctx->id; -} /* end get_cxn() */ - -/*****************************************************************************/ -/* - * restore the current TLB miss handler mapped page tables into the MMU context and set up a - * mapping for the page directory - */ -void change_mm_context(mm_context_t *old, mm_context_t *ctx, pgd_t *pgd) -{ - unsigned long _pgd; - - _pgd = virt_to_phys(pgd); - - /* save the state of the outgoing MMU context */ - old->id_busy = 0; - - asm volatile("movsg scr0,%0" : "=r"(old->itlb_cached_pge)); - asm volatile("movsg dampr4,%0" : "=r"(old->itlb_ptd_mapping)); - asm volatile("movsg scr1,%0" : "=r"(old->dtlb_cached_pge)); - asm volatile("movsg dampr5,%0" : "=r"(old->dtlb_ptd_mapping)); - - /* select an MMU context number */ - spin_lock(&cxn_owners_lock); - get_cxn(ctx); - ctx->id_busy = 1; - spin_unlock(&cxn_owners_lock); - - asm volatile("movgs %0,cxnr" : : "r"(ctx->id)); - - /* restore the state of the incoming MMU context */ - asm volatile("movgs %0,scr0" : : "r"(ctx->itlb_cached_pge)); - asm volatile("movgs %0,dampr4" : : "r"(ctx->itlb_ptd_mapping)); - asm volatile("movgs %0,scr1" : : "r"(ctx->dtlb_cached_pge)); - asm volatile("movgs %0,dampr5" : : "r"(ctx->dtlb_ptd_mapping)); - - /* map the PGD into uncached virtual memory */ - asm volatile("movgs %0,ttbr" : : "r"(_pgd)); - asm volatile("movgs %0,dampr3" - :: "r"(_pgd | xAMPRx_L | xAMPRx_M | xAMPRx_SS_16Kb | - xAMPRx_S | xAMPRx_C | xAMPRx_V)); - -} /* end change_mm_context() */ - -/*****************************************************************************/ -/* - * finished with an MMU context number - */ -void destroy_context(struct mm_struct *mm) -{ - mm_context_t *ctx = &mm->context; - - spin_lock(&cxn_owners_lock); - - if (!list_empty(&ctx->id_link)) { - if (ctx->id == cxn_pinned) - cxn_pinned = -1; - - list_del_init(&ctx->id_link); - clear_bit(ctx->id, cxn_bitmap); - __flush_tlb_mm(ctx->id); - ctx->id = 0; - } - - spin_unlock(&cxn_owners_lock); -} /* end destroy_context() */ - -/*****************************************************************************/ -/* - * display the MMU context currently a process is currently using - */ -#ifdef CONFIG_PROC_FS -char *proc_pid_status_frv_cxnr(struct mm_struct *mm, char *buffer) -{ - spin_lock(&cxn_owners_lock); - buffer += sprintf(buffer, "CXNR: %u\n", mm->context.id); - spin_unlock(&cxn_owners_lock); - - return buffer; -} /* end proc_pid_status_frv_cxnr() */ -#endif - -/*****************************************************************************/ -/* - * (un)pin a process's mm_struct's MMU context ID - */ -int cxn_pin_by_pid(pid_t pid) -{ - struct task_struct *tsk; - struct mm_struct *mm = NULL; - int ret; - - /* unpin if pid is zero */ - if (pid == 0) { - cxn_pinned = -1; - return 0; - } - - ret = -ESRCH; - - /* get a handle on the mm_struct */ - read_lock(&tasklist_lock); - tsk = find_task_by_vpid(pid); - if (tsk) { - ret = -EINVAL; - - task_lock(tsk); - if (tsk->mm) { - mm = tsk->mm; - mmget(mm); - ret = 0; - } - task_unlock(tsk); - } - read_unlock(&tasklist_lock); - - if (ret < 0) - return ret; - - /* make sure it has a CXN and pin it */ - spin_lock(&cxn_owners_lock); - cxn_pinned = get_cxn(&mm->context); - spin_unlock(&cxn_owners_lock); - - mmput(mm); - return 0; -} /* end cxn_pin_by_pid() */ |