On Wed, Sep 10, 2014 at 10:51:48AM -0600, Toshi Kani wrote: > This patch adds set_memory_wt(), set_memory_array_wt(), and > set_pages_array_wt() for setting range(s) of memory to WT. > > Note that set_memory_wt() only works for non-RAM ranges at > this point due to the current limitation in reserve_memtype(). > This may still be useful when a driver maps the entire NV-DIMM > range with ioremap_cache() and then modifies a specific range > to WT with set_memory_wt(). > > Signed-off-by: Toshi Kani <[email protected]>
Reviewed-by: Konrad Rzeszutek Wilk <[email protected]> > --- > arch/x86/include/asm/cacheflush.h | 6 +++ > arch/x86/mm/pageattr.c | 73 > ++++++++++++++++++++++++++++++++++--- > 2 files changed, 72 insertions(+), 7 deletions(-) > > diff --git a/arch/x86/include/asm/cacheflush.h > b/arch/x86/include/asm/cacheflush.h > index c912680..5bfd5d0 100644 > --- a/arch/x86/include/asm/cacheflush.h > +++ b/arch/x86/include/asm/cacheflush.h > @@ -81,7 +81,7 @@ static inline void set_page_memtype(struct page *pg, > /* > * The set_memory_* API can be used to change various attributes of a virtual > * address range. The attributes include: > - * Cachability : UnCached, WriteCombining, WriteBack > + * Cachability : UnCached, WriteCombining, WriteThrough, WriteBack > * Executability : eXeutable, NoteXecutable > * Read/Write : ReadOnly, ReadWrite > * Presence : NotPresent > @@ -108,9 +108,11 @@ static inline void set_page_memtype(struct page *pg, > > int _set_memory_uc(unsigned long addr, int numpages); > int _set_memory_wc(unsigned long addr, int numpages); > +int _set_memory_wt(unsigned long addr, int numpages); > int _set_memory_wb(unsigned long addr, int numpages); > int set_memory_uc(unsigned long addr, int numpages); > int set_memory_wc(unsigned long addr, int numpages); > +int set_memory_wt(unsigned long addr, int numpages); > int set_memory_wb(unsigned long addr, int numpages); > int set_memory_x(unsigned long addr, int numpages); > int set_memory_nx(unsigned long addr, int numpages); > @@ -121,10 +123,12 @@ int set_memory_4k(unsigned long addr, int numpages); > > int set_memory_array_uc(unsigned long *addr, int addrinarray); > int set_memory_array_wc(unsigned long *addr, int addrinarray); > +int set_memory_array_wt(unsigned long *addr, int addrinarray); > int set_memory_array_wb(unsigned long *addr, int addrinarray); > > int set_pages_array_uc(struct page **pages, int addrinarray); > int set_pages_array_wc(struct page **pages, int addrinarray); > +int set_pages_array_wt(struct page **pages, int addrinarray); > int set_pages_array_wb(struct page **pages, int addrinarray); > > /* > diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c > index 6917b39..2dda151 100644 > --- a/arch/x86/mm/pageattr.c > +++ b/arch/x86/mm/pageattr.c > @@ -1484,12 +1484,10 @@ EXPORT_SYMBOL(set_memory_uc); > static int _set_memory_array(unsigned long *addr, int addrinarray, > enum page_cache_mode new_type) > { > + enum page_cache_mode set_type; > int i, j; > int ret; > > - /* > - * for now UC MINUS. see comments in ioremap_nocache() > - */ > for (i = 0; i < addrinarray; i++) { > ret = reserve_memtype(__pa(addr[i]), __pa(addr[i]) + PAGE_SIZE, > new_type, NULL); > @@ -1497,9 +1495,12 @@ static int _set_memory_array(unsigned long *addr, int > addrinarray, > goto out_free; > } > > + /* If WC, set to UC- first and then WC */ > + set_type = (new_type == _PAGE_CACHE_MODE_WC) ? > + _PAGE_CACHE_MODE_UC_MINUS : new_type; > + > ret = change_page_attr_set(addr, addrinarray, > - cachemode2pgprot(_PAGE_CACHE_MODE_UC_MINUS), > - 1); > + cachemode2pgprot(set_type), 1); > > if (!ret && new_type == _PAGE_CACHE_MODE_WC) > ret = change_page_attr_set_clr(addr, addrinarray, > @@ -1527,10 +1528,22 @@ EXPORT_SYMBOL(set_memory_array_uc); > > int set_memory_array_wc(unsigned long *addr, int addrinarray) > { > + if (!pat_enabled) > + return set_memory_array_uc(addr, addrinarray); > + > return _set_memory_array(addr, addrinarray, _PAGE_CACHE_MODE_WC); > } > EXPORT_SYMBOL(set_memory_array_wc); > > +int set_memory_array_wt(unsigned long *addr, int addrinarray) > +{ > + if (!pat_enabled) > + return set_memory_array_uc(addr, addrinarray); > + > + return _set_memory_array(addr, addrinarray, _PAGE_CACHE_MODE_WT); > +} > +EXPORT_SYMBOL(set_memory_array_wt); > + > int _set_memory_wc(unsigned long addr, int numpages) > { > int ret; > @@ -1574,6 +1587,37 @@ out_err: > } > EXPORT_SYMBOL(set_memory_wc); > > +int _set_memory_wt(unsigned long addr, int numpages) > +{ > + return change_page_attr_set(&addr, numpages, > + cachemode2pgprot(_PAGE_CACHE_MODE_WT), 0); > +} > + > +int set_memory_wt(unsigned long addr, int numpages) > +{ > + int ret; > + > + if (!pat_enabled) > + return set_memory_uc(addr, numpages); > + > + ret = reserve_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE, > + _PAGE_CACHE_MODE_WT, NULL); > + if (ret) > + goto out_err; > + > + ret = _set_memory_wt(addr, numpages); > + if (ret) > + goto out_free; > + > + return 0; > + > +out_free: > + free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE); > +out_err: > + return ret; > +} > +EXPORT_SYMBOL(set_memory_wt); > + > int _set_memory_wb(unsigned long addr, int numpages) > { > /* WB cache mode is hard wired to all cache attribute bits being 0 */ > @@ -1666,6 +1710,7 @@ static int _set_pages_array(struct page **pages, int > addrinarray, > { > unsigned long start; > unsigned long end; > + enum page_cache_mode set_type; > int i; > int free_idx; > int ret; > @@ -1679,8 +1724,12 @@ static int _set_pages_array(struct page **pages, int > addrinarray, > goto err_out; > } > > + /* If WC, set to UC- first and then WC */ > + set_type = (new_type == _PAGE_CACHE_MODE_WC) ? > + _PAGE_CACHE_MODE_UC_MINUS : new_type; > + > ret = cpa_set_pages_array(pages, addrinarray, > - cachemode2pgprot(_PAGE_CACHE_MODE_UC_MINUS)); > + cachemode2pgprot(set_type)); > if (!ret && new_type == _PAGE_CACHE_MODE_WC) > ret = change_page_attr_set_clr(NULL, addrinarray, > cachemode2pgprot( > @@ -1710,10 +1759,22 @@ EXPORT_SYMBOL(set_pages_array_uc); > > int set_pages_array_wc(struct page **pages, int addrinarray) > { > + if (!pat_enabled) > + return set_pages_array_uc(pages, addrinarray); > + > return _set_pages_array(pages, addrinarray, _PAGE_CACHE_MODE_WC); > } > EXPORT_SYMBOL(set_pages_array_wc); > > +int set_pages_array_wt(struct page **pages, int addrinarray) > +{ > + if (!pat_enabled) > + return set_pages_array_uc(pages, addrinarray); > + > + return _set_pages_array(pages, addrinarray, _PAGE_CACHE_MODE_WT); > +} > +EXPORT_SYMBOL(set_pages_array_wt); > + > int set_pages_wb(struct page *page, int numpages) > { > unsigned long addr = (unsigned long)page_address(page); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
