[PATCH v2 6/9] mtip32xx: Handle safe removal during IO

From: Asai Thambi SP
Date: Thu Feb 25 2016 - 00:18:25 EST



Flush inflight IOs using fsync_bdev() when the device is safely
removed. Also, block further IOs in device open function.

Signed-off-by: Selvan Mani <smani@xxxxxxxxxx>
Signed-off-by: Rajesh Kumar Sambandam <rsambandam@xxxxxxxxxx>
Signed-off-by: Asai Thambi S P <asamymuthupa@xxxxxxxxxx>
---
drivers/block/mtip32xx/mtip32xx.c | 34 ++++++++++++++++++++++++++++++++--
drivers/block/mtip32xx/mtip32xx.h | 1 +
2 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
index 4c4d13a..6268ea0 100644
--- a/drivers/block/mtip32xx/mtip32xx.c
+++ b/drivers/block/mtip32xx/mtip32xx.c
@@ -3595,6 +3595,28 @@ static int mtip_block_getgeo(struct block_device *dev,
return 0;
}

+static int mtip_block_open(struct block_device *dev, fmode_t mode)
+{
+ struct driver_data *dd;
+
+ if (dev && dev->bd_disk) {
+ dd = (struct driver_data *) dev->bd_disk->private_data;
+
+ if (dd) {
+ if (test_bit(MTIP_DDF_REMOVAL_BIT,
+ &dd->dd_flag)) {
+ return -ENODEV;
+ }
+ return 0;
+ }
+ }
+ return -ENODEV;
+}
+
+void mtip_block_release(struct gendisk *disk, fmode_t mode)
+{
+}
+
/*
* Block device operation function.
*
@@ -3602,6 +3624,8 @@ static int mtip_block_getgeo(struct block_device *dev,
* layer.
*/
static const struct block_device_operations mtip_block_ops = {
+ .open = mtip_block_open,
+ .release = mtip_block_release,
.ioctl = mtip_block_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = mtip_block_compat_ioctl,
@@ -4427,7 +4451,7 @@ static void mtip_pci_remove(struct pci_dev *pdev)
struct driver_data *dd = pci_get_drvdata(pdev);
unsigned long flags, to;

- set_bit(MTIP_DDF_REMOVE_PENDING_BIT, &dd->dd_flag);
+ set_bit(MTIP_DDF_REMOVAL_BIT, &dd->dd_flag);

spin_lock_irqsave(&dev_lock, flags);
list_del_init(&dd->online_list);
@@ -4444,12 +4468,18 @@ static void mtip_pci_remove(struct pci_dev *pdev)
} while (atomic_read(&dd->irq_workers_active) != 0 &&
time_before(jiffies, to));

+ fsync_bdev(dd->bdev);
+
if (atomic_read(&dd->irq_workers_active) != 0) {
dev_warn(&dd->pdev->dev,
"Completion workers still active!\n");
}

- blk_mq_stop_hw_queues(dd->queue);
+ if (dd->sr)
+ blk_mq_stop_hw_queues(dd->queue);
+
+ set_bit(MTIP_DDF_REMOVE_PENDING_BIT, &dd->dd_flag);
+
/* Clean up the block layer. */
mtip_block_remove(dd);

diff --git a/drivers/block/mtip32xx/mtip32xx.h b/drivers/block/mtip32xx/mtip32xx.h
index 8635239..50af742 100644
--- a/drivers/block/mtip32xx/mtip32xx.h
+++ b/drivers/block/mtip32xx/mtip32xx.h
@@ -158,6 +158,7 @@ enum {
MTIP_DDF_RESUME_BIT = 6,
MTIP_DDF_INIT_DONE_BIT = 7,
MTIP_DDF_REBUILD_FAILED_BIT = 8,
+ MTIP_DDF_REMOVAL_BIT = 9,

MTIP_DDF_STOP_IO = ((1 << MTIP_DDF_REMOVE_PENDING_BIT) |
(1 << MTIP_DDF_SEC_LOCK_BIT) |
--
1.7.1