[PATCH 06/13] drm: add helper to clflush a virtual address range

Daniel Vetter
2011-11-06T19:13:53Z

Useful when the page is already mapped to copy date in/out.

Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
---
drivers/gpu/drm/drm_cache.c | 23 +++++++++++++++++++++++
include/drm/drmP.h | 1 +
2 files changed, 24 insertions(+), 0 deletions(-)

diff --git a/drivers/gpu/drm/drm_cache.c b/drivers/gpu/drm/drm_cache.c
index 0e3bd5b..502771a 100644
--- a/drivers/gpu/drm/drm_cache.c
+++ b/drivers/gpu/drm/drm_cache.c
@@ -97,3 +97,26 @@ drm_clflush_pages(struct page *pages[], unsigned long num_pages)
#endif
}
EXPORT_SYMBOL(drm_clflush_pages);
+
+void
+drm_clflush_virt_range(char *addr, unsigned long length)
+{
+#if defined(CONFIG_X86)
+ if (cpu_has_clflush) {
+ char *end = addr + length;
+ mb();
+ for (; addr < end; addr += boot_cpu_data.x86_clflush_size)
+ clflush(addr);
+ clflush(end - 1);
+ mb();
+ return;
+ }
+
+ if (on_each_cpu(drm_clflush_ipi_handler, NULL, 1) != 0)
+ printk(KERN_ERR "Timed out waiting for cache flush.\n");
+#else
+ printk(KERN_ERR "Architecture has no drm_cache.c support\n");
+ WARN_ON_ONCE(1);
+#endif
+}
+EXPORT_SYMBOL(drm_clflush_virt_range);
diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index 43538b6..a082640 100644
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -1328,6 +1328,7 @@ extern int drm_authmagic(struct drm_device *dev, void *data,

/* Cache management (drm_cache.c) */
void drm_clflush_pages(struct page *pages[], unsigned long num_pages);
+void drm_clflush_virt_range(char *addr, unsigned long length);

/* Locking IOCTL support (drm_lock.h) */
extern int drm_lock(struct drm_device *dev, void *data,
--
1.7.6.4