Introduce a function forget_buffer_locked that forgets a range of
buffers. It is more efficient than calling forget_buffer in a loop.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
There is no user for this interface. If in future it is needed it can
be reimplemented to walk the rbtree of buffers instead of doing
block-by-block lookups.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Add functions dm_bufio_issue_discard and dm_bufio_discard_buffers.
dm_bufio_issue_discard sends discard request to the underlying device.
dm_bufio_discard_buffers frees buffers in the range and then calls
dm_bufio_issue_discard.
Also, factor out block_to_sector for reuse in dm_bufio_issue_discard.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Move dm-bufio.h to include/linux/ so that external GPL'd DM target
modules can use it.
It is better to allow the use of dm-bufio than force external modules
to implement the equivalent buffered IO mechanism in some new way. The
hope is this will encourage the use of dm-bufio; which will then make it
easier for a GPL'd external DM target module to be included upstream.
A couple dm-bufio EXPORT_SYMBOL exports have also been updated to use
EXPORT_SYMBOL_GPL.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
