blob: 7ddd1b8d6910a882bc1e8639367978c5adc95816 [file] [log] [blame]
* Copyright 2010 Tilera Corporation. All Rights Reserved.
* 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, version 2.
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* NON INFRINGEMENT. See the GNU General Public License for
* more details.
* Handle issues around the Tile "home cache" model of coherence.
#include <asm/page.h>
#include <linux/cpumask.h>
struct page;
struct task_struct;
struct vm_area_struct;
struct zone;
* Coherence point for the page is its memory controller.
* It is not present in any cache (L1 or L2).
* Is this page immutable (unwritable) and thus able to be cached more
* widely than would otherwise be possible? This means we have "nc" set.
* Each cpu considers its own cache to be the home for the page,
* which makes it incoherent.
/* Home for the page is distributed via hash-for-home. */
#define PAGE_HOME_HASH -4
/* Support wrapper to use instead of explicit hv_flush_remote(). */
extern void flush_remote(unsigned long cache_pfn, unsigned long cache_length,
const struct cpumask *cache_cpumask,
HV_VirtAddr tlb_va, unsigned long tlb_length,
unsigned long tlb_pgsize,
const struct cpumask *tlb_cpumask,
HV_Remote_ASID *asids, int asidcount);
/* Set homing-related bits in a PTE (can also pass a pgprot_t). */
extern pte_t pte_set_home(pte_t pte, int home);
/* Do a cache eviction on the specified cpus. */
extern void homecache_evict(const struct cpumask *mask);
* Change a kernel page's homecache. It must not be mapped in user space.
* If !CONFIG_HOMECACHE, only usable on LOWMEM, and can only be called when
* no other cpu can reference the page, and causes a full-chip cache/TLB flush.
extern void homecache_change_page_home(struct page *, int order, int home);
* Flush a page out of whatever cache(s) it is in.
* This is more than just finv, since it properly handles waiting
* for the data to reach memory, but it can be quite
* heavyweight, particularly on incoherent or immutable memory.
extern void homecache_finv_page(struct page *);
* Flush a page out of the specified home cache.
* Note that the specified home need not be the actual home of the page,
* as for example might be the case when coordinating with I/O devices.
extern void homecache_finv_map_page(struct page *, int home);
* Allocate a page with the given GFP flags, home, and optionally
* node. These routines are actually just wrappers around the normal
* alloc_pages() / alloc_pages_node() functions, which set and clear
* a per-cpu variable to communicate with homecache_new_kernel_page().
* If !CONFIG_HOMECACHE, uses homecache_change_page_home().
extern struct page *homecache_alloc_pages(gfp_t gfp_mask,
unsigned int order, int home);
extern struct page *homecache_alloc_pages_node(int nid, gfp_t gfp_mask,
unsigned int order, int home);
#define homecache_alloc_page(gfp_mask, home) \
homecache_alloc_pages(gfp_mask, 0, home)
* These routines are just pass-throughs to free_pages() when
* we support full homecaching. If !CONFIG_HOMECACHE, then these
* routines use homecache_change_page_home() to reset the home
* back to the default before returning the page to the allocator.
void __homecache_free_pages(struct page *, unsigned int order);
void homecache_free_pages(unsigned long addr, unsigned int order);
#define __homecache_free_page(page) __homecache_free_pages((page), 0)
#define homecache_free_page(page) homecache_free_pages((page), 0)
* Report the page home for LOWMEM pages by examining their kernel PTE,
* or for highmem pages as the default home.
extern int page_home(struct page *);
#define homecache_migrate_kthread() do {} while (0)
#define homecache_kpte_lock() 0
#define homecache_kpte_unlock(flags) do {} while (0)
#endif /* _ASM_TILE_HOMECACHE_H */