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| author | Daniel Vetter <daniel.vetter@ffwll.ch> | 2011-09-28 11:57:23 +0200 |
|---|---|---|
| committer | Keith Packard <keithp@keithp.com> | 2011-10-20 15:26:17 -0700 |
| commit | 24dd85ff723f142093f44244764b9b5c152235b8 (patch) | |
| tree | 142aaa2cf68b307e584ed1ba9f40a951ae46828c /include/linux | |
| parent | 8ffc02468145ac92b1b88896e0f18bd7bcd52591 (diff) | |
| download | lwn-24dd85ff723f142093f44244764b9b5c152235b8.tar.gz lwn-24dd85ff723f142093f44244764b9b5c152235b8.zip | |
io-mapping: ensure io_mapping_map_atomic _is_ atomic
For the !HAVE_ATOMIC_IOMAP case the stub functions did not call
pagefault_disable/_enable. The i915 driver relies on the map
actually being atomic, otherwise it can deadlock with it's own
pagefault handler in the gtt pwrite fastpath.
This is exercised by gem_mmap_gtt from the intel-gpu-toosl gem
testsuite.
v2: Chris Wilson noted the lack of an include.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=38115
Cc: stable@kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Keith Packard <keithp@keithp.com>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/io-mapping.h | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/include/linux/io-mapping.h b/include/linux/io-mapping.h index 8cdcc2a199ad..1feeb5263565 100644 --- a/include/linux/io-mapping.h +++ b/include/linux/io-mapping.h @@ -117,6 +117,8 @@ io_mapping_unmap(void __iomem *vaddr) #else +#include <linux/uaccess.h> + /* this struct isn't actually defined anywhere */ struct io_mapping; @@ -138,12 +140,14 @@ static inline void __iomem * io_mapping_map_atomic_wc(struct io_mapping *mapping, unsigned long offset) { + pagefault_disable(); return ((char __force __iomem *) mapping) + offset; } static inline void io_mapping_unmap_atomic(void __iomem *vaddr) { + pagefault_enable(); } /* Non-atomic map/unmap */ |