arch/sparc/mm/srmmu.c

Source file repositories/reference/linux-study-clean/arch/sparc/mm/srmmu.c

File Facts

System
Linux kernel
Corpus path
arch/sparc/mm/srmmu.c
Extension
.c
Size
49101 bytes
Lines
1803
Domain
Architecture Layer
Bucket
arch/sparc
Inferred role
Architecture Layer: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

struct ctx_list {
	struct ctx_list *next;
	struct ctx_list *prev;
	unsigned int ctx_number;
	struct mm_struct *ctx_mm;
};

static struct ctx_list *ctx_list_pool;
static struct ctx_list ctx_free;
static struct ctx_list ctx_used;

/* At boot time we determine the number of contexts */
static int num_contexts;

static inline void remove_from_ctx_list(struct ctx_list *entry)
{
	entry->next->prev = entry->prev;
	entry->prev->next = entry->next;
}

static inline void add_to_ctx_list(struct ctx_list *head, struct ctx_list *entry)
{
	entry->next = head;
	(entry->prev = head->prev)->next = entry;
	head->prev = entry;
}
#define add_to_free_ctxlist(entry) add_to_ctx_list(&ctx_free, entry)
#define add_to_used_ctxlist(entry) add_to_ctx_list(&ctx_used, entry)


static inline void alloc_context(struct mm_struct *old_mm, struct mm_struct *mm)
{
	struct ctx_list *ctxp;

	ctxp = ctx_free.next;
	if (ctxp != &ctx_free) {
		remove_from_ctx_list(ctxp);
		add_to_used_ctxlist(ctxp);
		mm->context = ctxp->ctx_number;
		ctxp->ctx_mm = mm;
		return;
	}
	ctxp = ctx_used.next;
	if (ctxp->ctx_mm == old_mm)
		ctxp = ctxp->next;
	if (ctxp == &ctx_used)
		panic("out of mmu contexts");
	flush_cache_mm(ctxp->ctx_mm);
	flush_tlb_mm(ctxp->ctx_mm);
	remove_from_ctx_list(ctxp);
	add_to_used_ctxlist(ctxp);
	ctxp->ctx_mm->context = NO_CONTEXT;
	ctxp->ctx_mm = mm;
	mm->context = ctxp->ctx_number;
}

static inline void free_context(int context)
{
	struct ctx_list *ctx_old;

	ctx_old = ctx_list_pool + context;
	remove_from_ctx_list(ctx_old);
	add_to_free_ctxlist(ctx_old);
}

static void __init sparc_context_init(int numctx)
{
	int ctx;
	unsigned long size;

	size = numctx * sizeof(struct ctx_list);
	ctx_list_pool = memblock_alloc_or_panic(size, SMP_CACHE_BYTES);

	for (ctx = 0; ctx < numctx; ctx++) {
		struct ctx_list *clist;

		clist = (ctx_list_pool + ctx);
		clist->ctx_number = ctx;
		clist->ctx_mm = NULL;
	}
	ctx_free.next = ctx_free.prev = &ctx_free;
	ctx_used.next = ctx_used.prev = &ctx_used;
	for (ctx = 0; ctx < numctx; ctx++)
		add_to_free_ctxlist(ctx_list_pool + ctx);
}

void switch_mm(struct mm_struct *old_mm, struct mm_struct *mm,
	       struct task_struct *tsk)
{
	unsigned long flags;

Annotation

Implementation Notes