s390/dasd: Fail all requests when DASD_FLAG_ABORTIO is set
Whenever a DASD request encounters a timeout we might
need to abort all outstanding requests on this or
even other devices.
This is especially useful if one wants to fail all
devices on one side of a RAID10 configuration, even
though only one device exhibited an error.
To handle this I've introduced a new device flag
DASD_FLAG_ABORTIO.
This flag is evaluated in __dasd_process_request_queue()
and will invoke blk_abort_request() for all
outstanding requests with DASD_CQR_FLAGS_FAILFAST set.
This will cause any of these requests to be aborted
immediately if the blk_timeout function is activated.
The DASD_FLAG_ABORTIO is also evaluated in
__dasd_process_request_queue to abort all
new request which would have the
DASD_CQR_FLAGS_FAILFAST bit set.
The flag can be set with the new ioctls 'BIODASDABORTIO'
and removed with 'BIODASDALLOWIO'.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/block/dasd_ioctl.c b/drivers/s390/block/dasd_ioctl.c
index 8be1b51..25a0f2f 100644
--- a/drivers/s390/block/dasd_ioctl.c
+++ b/drivers/s390/block/dasd_ioctl.c
@@ -141,6 +141,59 @@
}
/*
+ * Abort all failfast I/O on a device.
+ */
+static int dasd_ioctl_abortio(struct dasd_block *block)
+{
+ unsigned long flags;
+ struct dasd_device *base;
+ struct dasd_ccw_req *cqr, *n;
+
+ base = block->base;
+ if (!capable(CAP_SYS_ADMIN))
+ return -EACCES;
+
+ if (test_and_set_bit(DASD_FLAG_ABORTALL, &base->flags))
+ return 0;
+ DBF_DEV_EVENT(DBF_NOTICE, base, "%s", "abortall flag set");
+
+ spin_lock_irqsave(&block->request_queue_lock, flags);
+ spin_lock(&block->queue_lock);
+ list_for_each_entry_safe(cqr, n, &block->ccw_queue, blocklist) {
+ if (test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
+ cqr->callback_data &&
+ cqr->callback_data != DASD_SLEEPON_START_TAG &&
+ cqr->callback_data != DASD_SLEEPON_END_TAG) {
+ spin_unlock(&block->queue_lock);
+ blk_abort_request(cqr->callback_data);
+ spin_lock(&block->queue_lock);
+ }
+ }
+ spin_unlock(&block->queue_lock);
+ spin_unlock_irqrestore(&block->request_queue_lock, flags);
+
+ dasd_schedule_block_bh(block);
+ return 0;
+}
+
+/*
+ * Allow I/O on a device
+ */
+static int dasd_ioctl_allowio(struct dasd_block *block)
+{
+ struct dasd_device *base;
+
+ base = block->base;
+ if (!capable(CAP_SYS_ADMIN))
+ return -EACCES;
+
+ if (test_and_clear_bit(DASD_FLAG_ABORTALL, &base->flags))
+ DBF_DEV_EVENT(DBF_NOTICE, base, "%s", "abortall flag unset");
+
+ return 0;
+}
+
+/*
* performs formatting of _device_ according to _fdata_
* Note: The discipline's format_function is assumed to deliver formatting
* commands to format multiple units of the device. In terms of the ECKD
@@ -458,6 +511,12 @@
case BIODASDRESUME:
rc = dasd_ioctl_resume(block);
break;
+ case BIODASDABORTIO:
+ rc = dasd_ioctl_abortio(block);
+ break;
+ case BIODASDALLOWIO:
+ rc = dasd_ioctl_allowio(block);
+ break;
case BIODASDFMT:
rc = dasd_ioctl_format(bdev, argp);
break;