diff options
| author | Dan Williams <dan.j.williams@intel.com> | 2017-10-23 20:24:45 +0300 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2017-11-15 03:49:06 +0300 |
| commit | 7a862fbbdec665190c5ef298c0c6ec9f3915cf45 (patch) | |
| tree | 78f3f86aa6545576fbcfb4188169f484865b0fed /drivers/block/Kconfig | |
| parent | 66a86cc10945648cf506ef314b98deeb7af06419 (diff) | |
| download | linux-7a862fbbdec665190c5ef298c0c6ec9f3915cf45.tar.xz | |
brd: remove dax support
DAX support in brd is awkward because its backing page frames are
distinct from the ones provided by pmem, dcssblk, or axonram. We need
pfn_t_devmap() entries to fully support DAX, and the limited DAX support
for pfn_t_special() page frames is not interesting for brd when pmem is
already a superset of brd. Lastly, brd is the only dax capable driver
that may sleep in its ->direct_access() implementation. So it causes a
global burden with no net gain of kernel functionality.
For all these reasons, remove DAX support.
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/block/Kconfig')
| -rw-r--r-- | drivers/block/Kconfig | 12 |
1 files changed, 0 insertions, 12 deletions
diff --git a/drivers/block/Kconfig b/drivers/block/Kconfig index 2dfe99b328f8..da8bf0268ade 100644 --- a/drivers/block/Kconfig +++ b/drivers/block/Kconfig @@ -297,7 +297,6 @@ config BLK_DEV_SX8 config BLK_DEV_RAM tristate "RAM block device support" - select DAX if BLK_DEV_RAM_DAX ---help--- Saying Y here will allow you to use a portion of your RAM memory as a block device, so that you can make file systems on it, read and @@ -333,17 +332,6 @@ config BLK_DEV_RAM_SIZE The default value is 4096 kilobytes. Only change this if you know what you are doing. -config BLK_DEV_RAM_DAX - bool "Support Direct Access (DAX) to RAM block devices" - depends on BLK_DEV_RAM && FS_DAX - default n - help - Support filesystems using DAX to access RAM block devices. This - avoids double-buffering data in the page cache before copying it - to the block device. Answering Y will slightly enlarge the kernel, - and will prevent RAM block device backing store memory from being - allocated from highmem (only a problem for highmem systems). - config CDROM_PKTCDVD tristate "Packet writing on CD/DVD media (DEPRECATED)" depends on !UML |