From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: adam.manzanares@wdc.com To: viro@zeniv.linux.org.uk, bcrl@kvack.org Cc: linux-fsdevel@vger.kernel.org, linux-aio@kvack.org, linux-api@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, Adam Manzanares Subject: [PATCH v3 1/3] block: add ioprio_check_cap function Date: Tue, 8 May 2018 10:42:00 -0700 Message-Id: <20180508174202.2537-2-adam.manzanares@wdc.com> In-Reply-To: <20180508174202.2537-1-adam.manzanares@wdc.com> References: <20180508174202.2537-1-adam.manzanares@wdc.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: From: Adam Manzanares Aio per command iopriority support introduces a second interface between userland and the kernel capable of passing iopriority. The aio interface also needs the ability to verify that the submitting context has sufficient priviledges to submit IOPRIO_RT commands. This patch creates the ioprio_check_cap function to be used by the ioprio_set system call and also by the aio interface. Signed-off-by: Adam Manzanares --- block/ioprio.c | 22 ++++++++++++++++------ include/linux/ioprio.h | 2 ++ 2 files changed, 18 insertions(+), 6 deletions(-) diff --git a/block/ioprio.c b/block/ioprio.c index 6f5d0b6625e3..f9821080c92c 100644 --- a/block/ioprio.c +++ b/block/ioprio.c @@ -61,15 +61,10 @@ int set_task_ioprio(struct task_struct *task, int ioprio) } EXPORT_SYMBOL_GPL(set_task_ioprio); -SYSCALL_DEFINE3(ioprio_set, int, which, int, who, int, ioprio) +int ioprio_check_cap(int ioprio) { int class = IOPRIO_PRIO_CLASS(ioprio); int data = IOPRIO_PRIO_DATA(ioprio); - struct task_struct *p, *g; - struct user_struct *user; - struct pid *pgrp; - kuid_t uid; - int ret; switch (class) { case IOPRIO_CLASS_RT: @@ -92,6 +87,21 @@ SYSCALL_DEFINE3(ioprio_set, int, which, int, who, int, ioprio) return -EINVAL; } + return 0; +} + +SYSCALL_DEFINE3(ioprio_set, int, which, int, who, int, ioprio) +{ + struct task_struct *p, *g; + struct user_struct *user; + struct pid *pgrp; + kuid_t uid; + int ret; + + ret = ioprio_check_cap(ioprio); + if (ret) + return ret; + ret = -ESRCH; rcu_read_lock(); switch (which) { diff --git a/include/linux/ioprio.h b/include/linux/ioprio.h index 627efac73e6d..4a28cec49ec3 100644 --- a/include/linux/ioprio.h +++ b/include/linux/ioprio.h @@ -77,4 +77,6 @@ extern int ioprio_best(unsigned short aprio, unsigned short bprio); extern int set_task_ioprio(struct task_struct *task, int ioprio); +extern int ioprio_check_cap(int ioprio); + #endif -- 2.15.1