Binder buffers have always been mapped into kernel space via map_kernel_range_noflush() to allow the binder driver to modify the buffer before posting to userspace for processing. In recent Android releases, the number of long-running binder processes has increased to the point that for 32-bit systems, there is a risk of running out of vmalloc space. This patch set removes the persistent mapping of the binder buffers into kernel space. Instead, the binder driver creates temporary mappings with kmap() or kmap_atomic() to copy to or from the buffer only when necessary. Todd Kjos (7): binder: create userspace-to-binder-buffer copy function binder: add functions to copy to/from binder buffers binder: add function to copy binder object from buffer binder: avoid kernel vm_area for buffer fixups binder: remove kernel vm_area for buffer space binder: remove user_buffer_offset binder: use userspace pointer as base of buffer space drivers/android/Kconfig | 2 +- drivers/android/binder.c | 461 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++------------------------------------------------------------- drivers/android/binder_alloc.c | 302 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++------------------------------ drivers/android/binder_alloc.h | 47 +++++++++--------- drivers/android/binder_trace.h | 2 +- 5 files changed, 538 insertions(+), 276 deletions(-) _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
