diff options
author | Adam Manzanares <adam.manzanares@wdc.com> | 2018-05-22 10:52:17 -0700 |
---|---|---|
committer | Al Viro <viro@zeniv.linux.org.uk> | 2018-05-31 10:50:54 -0400 |
commit | aa43457799f715d76cb77342baab0615877e2b8a (patch) | |
tree | df9115b36ef602d0550e9c2626b5c53a705425ac | |
parent | 1da92779e2e8f309d5aecbbed346e7f812b174e8 (diff) |
block: add ioprio_check_cap function
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
privileges 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 <adam.manzanares@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
-rw-r--r-- | block/ioprio.c | 22 | ||||
-rw-r--r-- | 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 |