linux/drivers/media
Dan Williams b70131de64 v4l2: disable filesystem-dax mapping support
V4L2 memory registrations are incompatible with filesystem-dax that
needs the ability to revoke dma access to a mapping at will, or
otherwise allow the kernel to wait for completion of DMA.  The
filesystem-dax implementation breaks the traditional solution of
truncate of active file backed mappings since there is no page-cache
page we can orphan to sustain ongoing DMA.

If v4l2 wants to support long lived DMA mappings it needs to arrange to
hold a file lease or use some other mechanism so that the kernel can
coordinate revoking DMA access when the filesystem needs to truncate
mappings.

Link: http://lkml.kernel.org/r/151068940499.7446.12846708245365671207.stgit@dwillia2-desk3.amr.corp.intel.com
Fixes: 3565fce3a6 ("mm, x86: get_user_pages() for dax mappings")
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reported-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Doug Ledford <dledford@redhat.com>
Cc: Hal Rosenstock <hal.rosenstock@gmail.com>
Cc: Inki Dae <inki.dae@samsung.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Joonyoung Shim <jy0922.shim@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Sean Hefty <sean.hefty@intel.com>
Cc: Seung-Woo Kim <sw0312.kim@samsung.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-29 18:40:42 -08:00
..
cec media updates for v4.15-rc1 2017-11-15 20:30:12 -08:00
common treewide: Remove TIMER_FUNC_TYPE and TIMER_DATA_TYPE casts 2017-11-21 16:35:54 -08:00
dvb-core media updates for v4.15-rc1 2017-11-15 20:30:12 -08:00
dvb-frontends media updates for v4.15-rc1 2017-11-15 20:30:12 -08:00
firewire
i2c media updates for v4.15-rc1 2017-11-15 20:30:12 -08:00
mmc License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pci media updates for v4.15-rc1 2017-11-15 20:30:12 -08:00
platform treewide: setup_timer() -> timer_setup() (2 field) 2017-11-21 15:57:09 -08:00
radio media updates for v4.15-rc1 2017-11-15 20:30:12 -08:00
rc media updates for v4.15-rc1 2017-11-15 20:30:12 -08:00
spi [media] gs1662: drop kfree for memory allocated with devm_kzalloc 2016-10-24 17:59:08 -02:00
tuners License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
usb treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
v4l2-core v4l2: disable filesystem-dax mapping support 2017-11-29 18:40:42 -08:00
Kconfig media: rc-core: do not depend on MEDIA_SUPPORT 2017-08-20 09:39:36 -04:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
media-device.c media: drop use of MEDIA_API_VERSION 2017-08-08 06:03:15 -04:00
media-devnode.c media: utilize new cdev_device_add helper function 2017-03-21 06:44:33 +01:00
media-entity.c [media] media: Check for active and has_no_links overrun 2017-10-04 17:16:14 -03:00