On Thu, May 18, 2023 at 03:33:26PM -0700, Sarthak Kukreti wrote: > Add support for provision requests to loopback devices. > Loop devices will configure provision support based on > whether the underlying block device/file can support > the provision request and upon receiving a provision bio, > will map it to the backing device/storage. For loop devices > over files, a REQ_OP_PROVISION request will translate to > an fallocate mode 0 call on the backing file. > > Signed-off-by: Sarthak Kukreti <sarthakkukreti@xxxxxxxxxxxx> > --- > drivers/block/loop.c | 34 +++++++++++++++++++++++++++++++--- > 1 file changed, 31 insertions(+), 3 deletions(-) > > diff --git a/drivers/block/loop.c b/drivers/block/loop.c > index bc31bb7072a2..7fe1a6629754 100644 > --- a/drivers/block/loop.c > +++ b/drivers/block/loop.c > @@ -311,16 +311,20 @@ static int lo_fallocate(struct loop_device *lo, struct request *rq, loff_t pos, > { > /* > * We use fallocate to manipulate the space mappings used by the image > - * a.k.a. discard/zerorange. > + * a.k.a. discard/provision/zerorange. > */ > struct file *file = lo->lo_backing_file; > int ret; > > - mode |= FALLOC_FL_KEEP_SIZE; > + if (mode & (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_ZERO_RANGE) && > + !bdev_max_discard_sectors(lo->lo_device)) > + return -EOPNOTSUPP; > > - if (!bdev_max_discard_sectors(lo->lo_device)) > + if (mode == 0 && !bdev_max_provision_sectors(lo->lo_device)) > return -EOPNOTSUPP; > > + mode |= FALLOC_FL_KEEP_SIZE; > + > ret = file->f_op->fallocate(file, mode, pos, blk_rq_bytes(rq)); > if (unlikely(ret && ret != -EINVAL && ret != -EOPNOTSUPP)) > return -EIO; > @@ -488,6 +492,8 @@ static int do_req_filebacked(struct loop_device *lo, struct request *rq) > FALLOC_FL_PUNCH_HOLE); > case REQ_OP_DISCARD: > return lo_fallocate(lo, rq, pos, FALLOC_FL_PUNCH_HOLE); > + case REQ_OP_PROVISION: > + return lo_fallocate(lo, rq, pos, 0); If someone calls fallocate(UNSHARE_RANGE) on a loop bdev, shouldn't there be a way to pass that through to the fallocate call to the backing file? --D > case REQ_OP_WRITE: > if (cmd->use_aio) > return lo_rw_aio(lo, cmd, pos, ITER_SOURCE); > @@ -754,6 +760,25 @@ static void loop_sysfs_exit(struct loop_device *lo) > &loop_attribute_group); > } > > +static void loop_config_provision(struct loop_device *lo) > +{ > + struct file *file = lo->lo_backing_file; > + struct inode *inode = file->f_mapping->host; > + > + /* > + * If the backing device is a block device, mirror its provisioning > + * capability. > + */ > + if (S_ISBLK(inode->i_mode)) { > + blk_queue_max_provision_sectors(lo->lo_queue, > + bdev_max_provision_sectors(I_BDEV(inode))); > + } else if (file->f_op->fallocate) { > + blk_queue_max_provision_sectors(lo->lo_queue, UINT_MAX >> 9); > + } else { > + blk_queue_max_provision_sectors(lo->lo_queue, 0); > + } > +} > + > static void loop_config_discard(struct loop_device *lo) > { > struct file *file = lo->lo_backing_file; > @@ -1092,6 +1117,7 @@ static int loop_configure(struct loop_device *lo, fmode_t mode, > blk_queue_io_min(lo->lo_queue, bsize); > > loop_config_discard(lo); > + loop_config_provision(lo); > loop_update_rotational(lo); > loop_update_dio(lo); > loop_sysfs_init(lo); > @@ -1304,6 +1330,7 @@ loop_set_status(struct loop_device *lo, const struct loop_info64 *info) > } > > loop_config_discard(lo); > + loop_config_provision(lo); > > /* update dio if lo_offset or transfer is changed */ > __loop_update_dio(lo, lo->use_dio); > @@ -1830,6 +1857,7 @@ static blk_status_t loop_queue_rq(struct blk_mq_hw_ctx *hctx, > case REQ_OP_FLUSH: > case REQ_OP_DISCARD: > case REQ_OP_WRITE_ZEROES: > + case REQ_OP_PROVISION: > cmd->use_aio = false; > break; > default: > -- > 2.40.1.698.g37aff9b760-goog > > -- > dm-devel mailing list > dm-devel@xxxxxxxxxx > https://listman.redhat.com/mailman/listinfo/dm-devel > -- dm-devel mailing list dm-devel@xxxxxxxxxx https://listman.redhat.com/mailman/listinfo/dm-devel