Hi all, This quick series cleans up a few warts in the XFS GETFSMAP ioctl implementation. The first patch prevents an integer overflow when counting the mappings. The second patch improves performance of the ioctl by formatting reverse mappings to an in-kernel buffer and then copying the entire buffer to userspace (instead of copying the records one by one). That eliminates an indirect call and a lot of overhead from copying things to userspace, which is a bit expensive. It also fixes a deadlock when formatting rt fsmappings into a mmap region backed by sparse file on the rt device. v2: constrain the in-kernel memory buffer size If you're going to start using this mess, you probably ought to just pull from my git trees, which are linked below. This is an extraordinary way to destroy everything. Enjoy! Comments and questions are, as always, welcome. --D kernel git tree: https://git.kernel.org/cgit/linux/kernel/git/djwong/xfs-linux.git/log/?h=getfsmap-cleanups-5.10 --- fs/xfs/xfs_fsmap.c | 48 ++++++++++------- fs/xfs/xfs_fsmap.h | 6 -- fs/xfs/xfs_ioctl.c | 146 +++++++++++++++++++++++++++++++++++----------------- 3 files changed, 128 insertions(+), 72 deletions(-)
