#ifdef CONFIG_X86
static inline int ttm_tt_set_page_caching(struct page *p,
- enum ttm_caching_state c_state)
+ enum ttm_caching_state c_old,
+ enum ttm_caching_state c_new)
{
+ int ret = 0;
+
if (PageHighMem(p))
return 0;
- switch (c_state) {
- case tt_cached:
- return set_pages_wb(p, 1);
- case tt_wc:
- return set_memory_wc((unsigned long) page_address(p), 1);
- default:
- return set_pages_uc(p, 1);
+ if (c_old != tt_cached) {
+ /* p isn't in the default caching state, set it to
+ * writeback first to free its current memtype. */
+
+ ret = set_pages_wb(p, 1);
+ if (ret)
+ return ret;
}
+
+ if (c_new == tt_wc)
+ ret = set_memory_wc((unsigned long) page_address(p), 1);
+ else if (c_new == tt_uncached)
+ ret = set_pages_uc(p, 1);
+
+ return ret;
}
#else /* CONFIG_X86 */
static inline int ttm_tt_set_page_caching(struct page *p,
- enum ttm_caching_state c_state)
+ enum ttm_caching_state c_old,
+ enum ttm_caching_state c_new)
{
return 0;
}
for (i = 0; i < ttm->num_pages; ++i) {
cur_page = ttm->pages[i];
if (likely(cur_page != NULL)) {
- ret = ttm_tt_set_page_caching(cur_page, c_state);
+ ret = ttm_tt_set_page_caching(cur_page,
+ ttm->caching_state,
+ c_state);
if (unlikely(ret != 0))
goto out_err;
}
for (j = 0; j < i; ++j) {
cur_page = ttm->pages[j];
if (likely(cur_page != NULL)) {
- (void)ttm_tt_set_page_caching(cur_page,
+ (void)ttm_tt_set_page_caching(cur_page, c_state,
ttm->caching_state);
}
}