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Diffstat (limited to 'module/zfs/vdev_disk.c')
-rw-r--r--module/zfs/vdev_disk.c29
1 files changed, 12 insertions, 17 deletions
diff --git a/module/zfs/vdev_disk.c b/module/zfs/vdev_disk.c
index ec627a9c4..5cb3fe279 100644
--- a/module/zfs/vdev_disk.c
+++ b/module/zfs/vdev_disk.c
@@ -118,6 +118,12 @@ vdev_disk_error(zio_t *zio)
* automatically imported on module load so we must do this at device
* open time from the kernel.
*/
+#define SET_SCHEDULER_CMD \
+ "exec 0</dev/null " \
+ " 1>/sys/block/%s/queue/scheduler " \
+ " 2>/dev/null; " \
+ "echo %s"
+
static int
vdev_elevator_switch(vdev_t *v, char *elevator)
{
@@ -125,11 +131,9 @@ vdev_elevator_switch(vdev_t *v, char *elevator)
struct block_device *bdev = vd->vd_bdev;
struct request_queue *q = bdev_get_queue(bdev);
char *device = bdev->bd_disk->disk_name;
- char sh_path[] = "/bin/sh";
- char sh_cmd[128];
- char *argv[] = { sh_path, "-c", sh_cmd };
+ char *argv[] = { "/bin/sh", "-c", NULL, NULL };
char *envp[] = { NULL };
- int count = 0, error;
+ int error;
/* Skip devices which are not whole disks (partitions) */
if (!v->vdev_wholedisk)
@@ -143,23 +147,14 @@ vdev_elevator_switch(vdev_t *v, char *elevator)
if (!strncmp(elevator, "none", 4) && (strlen(elevator) == 4))
return (0);
- /*
- * Set the desired scheduler with a three attempt retry for
- * -EFAULT which has been observed to occur spuriously.
- */
- sprintf(sh_cmd, "%s \"%s\" >/sys/block/%s/queue/scheduler",
- "/bin/echo", elevator, device);
-
- while (++count <= 3) {
- error = call_usermodehelper(sh_path, argv, envp, 1);
- if ((error == 0) || (error != -EFAULT))
- break;
- }
-
+ argv[2] = kmem_asprintf(SET_SCHEDULER_CMD, device, elevator);
+ error = call_usermodehelper(argv[0], argv, envp, 1);
if (error)
printk("ZFS: Unable to set \"%s\" scheduler for %s (%s): %d\n",
elevator, v->vdev_path, device, error);
+ strfree(argv[2]);
+
return (error);
}