drm: add helper to clflush a virtual address range

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

For -stable because the next patch (fixing phys obj pwrite) needs this
little helper function.

Tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Daniel Vetter 2012-03-25 19:47:30 +02:00
parent dbf7bff074
commit 6d5cd9cb1e
2 changed files with 24 additions and 0 deletions

View File

@ -98,3 +98,26 @@ 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);

View File

@ -1332,6 +1332,7 @@ extern int drm_remove_magic(struct drm_master *master, drm_magic_t magic);
/* 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,