Hi Here I'm sending version 2 of the patch - it increases version number of the target, so that userspace can test if this feature is present. Mikulas From: Mikulas Patocka <mpatocka@xxxxxxxxxx> If we have discard support, we don't have to recalculate hash - we can just fill the metadata with the discard pattern. Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx> Index: linux-2.6/drivers/md/dm-integrity.c =================================================================== --- linux-2.6.orig/drivers/md/dm-integrity.c +++ linux-2.6/drivers/md/dm-integrity.c @@ -2690,26 +2690,30 @@ next_chunk: if (unlikely(dm_integrity_failed(ic))) goto err; - io_req.bi_op = REQ_OP_READ; - io_req.bi_op_flags = 0; - io_req.mem.type = DM_IO_VMA; - io_req.mem.ptr.addr = ic->recalc_buffer; - io_req.notify.fn = NULL; - io_req.client = ic->io; - io_loc.bdev = ic->dev->bdev; - io_loc.sector = get_data_sector(ic, area, offset); - io_loc.count = n_sectors; + if (!ic->discard) { + io_req.bi_op = REQ_OP_READ; + io_req.bi_op_flags = 0; + io_req.mem.type = DM_IO_VMA; + io_req.mem.ptr.addr = ic->recalc_buffer; + io_req.notify.fn = NULL; + io_req.client = ic->io; + io_loc.bdev = ic->dev->bdev; + io_loc.sector = get_data_sector(ic, area, offset); + io_loc.count = n_sectors; - r = dm_io(&io_req, 1, &io_loc, NULL); - if (unlikely(r)) { - dm_integrity_io_error(ic, "reading data", r); - goto err; - } + r = dm_io(&io_req, 1, &io_loc, NULL); + if (unlikely(r)) { + dm_integrity_io_error(ic, "reading data", r); + goto err; + } - t = ic->recalc_tags; - for (i = 0; i < n_sectors; i += ic->sectors_per_block) { - integrity_sector_checksum(ic, logical_sector + i, ic->recalc_buffer + (i << SECTOR_SHIFT), t); - t += ic->tag_size; + t = ic->recalc_tags; + for (i = 0; i < n_sectors; i += ic->sectors_per_block) { + integrity_sector_checksum(ic, logical_sector + i, ic->recalc_buffer + (i << SECTOR_SHIFT), t); + t += ic->tag_size; + } + } else { + t = ic->recalc_tags + (n_sectors >> ic->sb->log2_sectors_per_block) * ic->tag_size; } metadata_block = get_metadata_sector_and_offset(ic, area, offset, &metadata_offset); @@ -4364,11 +4368,13 @@ try_smaller_buffer: goto bad; } INIT_WORK(&ic->recalc_work, integrity_recalc); - ic->recalc_buffer = vmalloc(RECALC_SECTORS << SECTOR_SHIFT); - if (!ic->recalc_buffer) { - ti->error = "Cannot allocate buffer for recalculating"; - r = -ENOMEM; - goto bad; + if (!ic->discard) { + ic->recalc_buffer = vmalloc(RECALC_SECTORS << SECTOR_SHIFT); + if (!ic->recalc_buffer) { + ti->error = "Cannot allocate buffer for recalculating"; + r = -ENOMEM; + goto bad; + } } ic->recalc_tags = kvmalloc_array(RECALC_SECTORS >> ic->sb->log2_sectors_per_block, ic->tag_size, GFP_KERNEL); @@ -4377,6 +4383,8 @@ try_smaller_buffer: r = -ENOMEM; goto bad; } + if (ic->discard) + memset(ic->recalc_tags, DISCARD_FILLER, (RECALC_SECTORS >> ic->sb->log2_sectors_per_block) * ic->tag_size); } else { if (ic->sb->flags & cpu_to_le32(SB_FLAG_RECALCULATING)) { ti->error = "Recalculate can only be specified with internal_hash"; @@ -4570,7 +4578,7 @@ static void dm_integrity_dtr(struct dm_t static struct target_type integrity_target = { .name = "integrity", - .version = {1, 8, 0}, + .version = {1, 9, 0}, .module = THIS_MODULE, .features = DM_TARGET_SINGLETON | DM_TARGET_INTEGRITY, .ctr = dm_integrity_ctr, -- dm-devel mailing list dm-devel@xxxxxxxxxx https://listman.redhat.com/mailman/listinfo/dm-devel