From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:45414 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934653AbcCQOaj (ORCPT ); Thu, 17 Mar 2016 10:30:39 -0400 From: Brian Foster To: xfs@oss.sgi.com Cc: dm-devel@redhat.com, linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [RFC PATCH 7/9] dm thin: add method to provision space Date: Thu, 17 Mar 2016 10:30:35 -0400 Message-Id: <1458225037-24155-8-git-send-email-bfoster@redhat.com> In-Reply-To: <1458225037-24155-1-git-send-email-bfoster@redhat.com> References: <1458225037-24155-1-git-send-email-bfoster@redhat.com> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: This is a hacky interface added to support the filesystem experiment for reserving blocks out of thin pools. The XFS POC uses this method provision space in the pool when blocks are allocated. The number of actual blocks allocated is returned, which is used to update the filesystem accounting. Signed-off-by: Brian Foster --- drivers/md/dm-thin.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c index ac770d89..00b7322 100644 --- a/drivers/md/dm-thin.c +++ b/drivers/md/dm-thin.c @@ -4389,6 +4389,52 @@ static int thin_get_reserved_space(struct dm_target *ti, sector_t *nr_sects) return 0; } +static int thin_provision_space(struct dm_target *ti, sector_t offset, sector_t len) +{ + struct thin_c *tc = ti->private; + struct pool *pool = tc->pool; + sector_t end; + dm_block_t pblock; + dm_block_t vblock; + int error; + struct dm_thin_lookup_result lookup; + sector_t count; + + if (!is_factor(offset, pool->sectors_per_block)) + return -EINVAL; + + if (!len || !is_factor(len, pool->sectors_per_block)) + return -EINVAL; + + end = offset + len; + + count = 0; + while (offset < end) { + vblock = offset / pool->sectors_per_block; + + error = dm_thin_find_block(tc->td, vblock, true, &lookup); + if (error == 0) + goto next; + if (error != -ENODATA) + return error; + + error = alloc_data_block(tc, &pblock); + if (error) + return error; + + error = dm_thin_insert_block(tc->td, vblock, pblock); + if (error) + return error; + + count += pool->sectors_per_block; +next: + offset += pool->sectors_per_block; + } + + /* XXX: int -> sector_t ! */ + return count; +} + static struct target_type thin_target = { .name = "thin", .version = {1, 18, 0}, @@ -4405,6 +4451,7 @@ static struct target_type thin_target = { .io_hints = thin_io_hints, .reserve_space = thin_reserve_space, .get_reserved_space = thin_get_reserved_space, + .provision_space = thin_provision_space, }; /*----------------------------------------------------------------*/ -- 2.4.3