memremap: Change region_intersects() to take @flags and @desc

Change region_intersects() to identify a target with @flags and
@desc, instead of @name with strcmp().

Change the callers of region_intersects(), memremap() and
devm_memremap(), to set IORESOURCE_SYSTEM_RAM in @flags and
IORES_DESC_NONE in @desc when searching System RAM.

Also, export region_intersects() so that the ACPI EINJ error
injection driver can call this function in a later patch.

Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jakub Sitnicki <jsitnicki@gmail.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm <linux-mm@kvack.org>
Link: http://lkml.kernel.org/r/1453841853-11383-13-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 7 insertions, 6 deletions

diff --git a/kernel/memremap.c b/kernel/memremap.c
index e517a16cb426..293309cac061 100644
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -47,7 +47,7 @@ static void *try_ram_remap(resource_size_t offset, size_t size)
  * being mapped does not have i/o side effects and the __iomem
  * annotation is not applicable.
  *
- * MEMREMAP_WB - matches the default mapping for "System RAM" on
+ * MEMREMAP_WB - matches the default mapping for System RAM on
  * the architecture.  This is usually a read-allocate write-back cache.
  * Morever, if MEMREMAP_WB is specified and the requested remap region is RAM
  * memremap() will bypass establishing a new mapping and instead return
@@ -56,11 +56,12 @@ static void *try_ram_remap(resource_size_t offset, size_t size)
  * MEMREMAP_WT - establish a mapping whereby writes either bypass the
  * cache or are written through to memory and never exist in a
  * cache-dirty state with respect to program visibility.  Attempts to
- * map "System RAM" with this mapping type will fail.
+ * map System RAM with this mapping type will fail.
  */
 void *memremap(resource_size_t offset, size_t size, unsigned long flags)
 {
-	int is_ram = region_intersects(offset, size, "System RAM");
+	int is_ram = region_intersects(offset, size,
+				       IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE);
 	void *addr = NULL;
 
 	if (is_ram == REGION_MIXED) {
@@ -76,7 +77,7 @@ void *memremap(resource_size_t offset, size_t size, unsigned long flags)
 		 * MEMREMAP_WB is special in that it can be satisifed
 		 * from the direct map.  Some archs depend on the
 		 * capability of memremap() to autodetect cases where
-		 * the requested range is potentially in "System RAM"
+		 * the requested range is potentially in System RAM.
 		 */
 		if (is_ram == REGION_INTERSECTS)
 			addr = try_ram_remap(offset, size);
@@ -88,7 +89,7 @@ void *memremap(resource_size_t offset, size_t size, unsigned long flags)
 	 * If we don't have a mapping yet and more request flags are
 	 * pending then we will be attempting to establish a new virtual
 	 * address mapping.  Enforce that this mapping is not aliasing
-	 * "System RAM"
+	 * System RAM.
 	 */
 	if (!addr && is_ram == REGION_INTERSECTS && flags) {
 		WARN_ONCE(1, "memremap attempted on ram %pa size: %#lx\n",
@@ -266,7 +267,7 @@ void *devm_memremap_pages(struct device *dev, struct resource *res,
 		struct percpu_ref *ref, struct vmem_altmap *altmap)
 {
 	int is_ram = region_intersects(res->start, resource_size(res),
-			"System RAM");
+				       IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE);
 	resource_size_t key, align_start, align_size;
 	struct dev_pagemap *pgmap;
 	struct page_map *page_map;