treewide: move set_memory_* functions away from cacheflush.h

Patch series "set_memory_* functions header refactor", v3.

The set_memory_* APIs came out of a desire to have a better way to
change memory attributes.  Many of these attributes were linked to cache
functionality so the prototypes were put in cacheflush.h.  These days,
the APIs have grown and have a much wider use than just cache APIs.  To
support this growth, split off set_memory_* and friends into a separate
header file to avoid growing cacheflush.h for APIs that have nothing to
do with caches.

Link: http://lkml.kernel.org/r/1488920133-27229-2-git-send-email-labbott@redhat.com
Signed-off-by: Laura Abbott <labbott@redhat.com>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 87 insertions, 0 deletions

diff --git a/arch/x86/include/asm/set_memory.h b/arch/x86/include/asm/set_memory.h
new file mode 100644
index 0000000000000..eaec6c364e42d
--- /dev/null
+++ b/arch/x86/include/asm/set_memory.h
@@ -0,0 +1,87 @@
+#ifndef _ASM_X86_SET_MEMORY_H
+#define _ASM_X86_SET_MEMORY_H
+
+#include <asm/page.h>
+#include <asm-generic/set_memory.h>
+
+/*
+ * The set_memory_* API can be used to change various attributes of a virtual
+ * address range. The attributes include:
+ * Cachability   : UnCached, WriteCombining, WriteThrough, WriteBack
+ * Executability : eXeutable, NoteXecutable
+ * Read/Write    : ReadOnly, ReadWrite
+ * Presence      : NotPresent
+ *
+ * Within a category, the attributes are mutually exclusive.
+ *
+ * The implementation of this API will take care of various aspects that
+ * are associated with changing such attributes, such as:
+ * - Flushing TLBs
+ * - Flushing CPU caches
+ * - Making sure aliases of the memory behind the mapping don't violate
+ *   coherency rules as defined by the CPU in the system.
+ *
+ * What this API does not do:
+ * - Provide exclusion between various callers - including callers that
+ *   operation on other mappings of the same physical page
+ * - Restore default attributes when a page is freed
+ * - Guarantee that mappings other than the requested one are
+ *   in any state, other than that these do not violate rules for
+ *   the CPU you have. Do not depend on any effects on other mappings,
+ *   CPUs other than the one you have may have more relaxed rules.
+ * The caller is required to take care of these.
+ */
+
+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_np(unsigned long addr, int numpages);
+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);
+
+/*
+ * For legacy compatibility with the old APIs, a few functions
+ * are provided that work on a "struct page".
+ * These functions operate ONLY on the 1:1 kernel mapping of the
+ * memory that the struct page represents, and internally just
+ * call the set_memory_* function. See the description of the
+ * set_memory_* function for more details on conventions.
+ *
+ * These APIs should be considered *deprecated* and are likely going to
+ * be removed in the future.
+ * The reason for this is the implicit operation on the 1:1 mapping only,
+ * making this not a generally useful API.
+ *
+ * Specifically, many users of the old APIs had a virtual address,
+ * called virt_to_page() or vmalloc_to_page() on that address to
+ * get a struct page* that the old API required.
+ * To convert these cases, use set_memory_*() on the original
+ * virtual address, do not use these functions.
+ */
+
+int set_pages_uc(struct page *page, int numpages);
+int set_pages_wb(struct page *page, int numpages);
+int set_pages_x(struct page *page, int numpages);
+int set_pages_nx(struct page *page, int numpages);
+int set_pages_ro(struct page *page, int numpages);
+int set_pages_rw(struct page *page, int numpages);
+
+extern int kernel_set_to_readonly;
+void set_kernel_text_rw(void);
+void set_kernel_text_ro(void);
+
+#endif /* _ASM_X86_SET_MEMORY_H */