From 36aa9e5f591e84d67aad2c5bff75e413d77660dd Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 18 Aug 2015 14:55:31 -0700 Subject: blkcg: move body parsing from blkg_conf_prep() to its callers Currently, blkg_conf_prep() expects input to be of the following form MAJ:MIN NUM and reads the NUM part into blkg_conf_ctx->v. This is quite restrictive and gets in the way in implementing blkcg interface for the unified hierarchy. This patch updates blkg_conf_prep() so that it expects MAJ:MIN BODY_STR where BODY_STR is an arbitrary string. blkg_conf_ctx->v is replaced with ->body which is a char pointer pointing to the start of BODY_STR. Parsing of the body is moved to blkg_conf_prep()'s callers. To allow using, for example, strsep() on blkg_conf_ctx->val, it is a non-const pointer and to accommodate that const is dropped from @input too. This doesn't cause any behavior changes. Signed-off-by: Tejun Heo Signed-off-by: Jens Axboe --- block/blk-throttle.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) (limited to 'block/blk-throttle.c') diff --git a/block/blk-throttle.c b/block/blk-throttle.c index 8b4f6b81bb72..0e17c8f92d25 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -1154,21 +1154,25 @@ static ssize_t tg_set_conf(struct kernfs_open_file *of, struct blkcg_gq *blkg; struct cgroup_subsys_state *pos_css; int ret; + u64 v; ret = blkg_conf_prep(blkcg, &blkcg_policy_throtl, buf, &ctx); if (ret) return ret; + ret = -EINVAL; + if (sscanf(ctx.body, "%llu", &v) != 1) + goto out_finish; + if (!v) + v = -1; + tg = blkg_to_tg(ctx.blkg); sq = &tg->service_queue; - if (!ctx.v) - ctx.v = -1; - if (is_u64) - *(u64 *)((void *)tg + of_cft(of)->private) = ctx.v; + *(u64 *)((void *)tg + of_cft(of)->private) = v; else - *(unsigned int *)((void *)tg + of_cft(of)->private) = ctx.v; + *(unsigned int *)((void *)tg + of_cft(of)->private) = v; throtl_log(&tg->service_queue, "limit change rbps=%llu wbps=%llu riops=%u wiops=%u", @@ -1201,8 +1205,10 @@ static ssize_t tg_set_conf(struct kernfs_open_file *of, throtl_schedule_next_dispatch(sq->parent_sq, true); } + ret = 0; +out_finish: blkg_conf_finish(&ctx); - return nbytes; + return ret ?: nbytes; } static ssize_t tg_set_conf_u64(struct kernfs_open_file *of, -- cgit v1.2.3