summaryrefslogtreecommitdiff
path: root/block
diff options
context:
space:
mode:
authorChristoph Hellwig <hch@lst.de>2015-10-15 14:10:48 +0200
committerJens Axboe <axboe@fb.com>2015-10-21 14:46:56 -0600
commitbbd3e064362e5057cc4799ba2e4d68c7593e490b (patch)
tree94c1efd47cf05eaf940e3381bb4eb9df421ae001 /block
parentd8e4bb8103df02a2c509868732dc93fb66110a12 (diff)
downloadlinux-sh-bbd3e064362e5057cc4799ba2e4d68c7593e490b.tar.gz
block: add an API for Persistent Reservations
This commits adds a driver API and ioctls for controlling Persistent Reservations s/genericly/generically/ at the block layer. Persistent Reservations are supported by SCSI and NVMe and allow controlling who gets access to a device in a shared storage setup. Note that we add a pr_ops structure to struct block_device_operations instead of adding the members directly to avoid bloating all instances of devices that will never support Persistent Reservations. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'block')
-rw-r--r--block/ioctl.c103
1 files changed, 103 insertions, 0 deletions
diff --git a/block/ioctl.c b/block/ioctl.c
index df62b47d2379..0918aed2d847 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -7,6 +7,7 @@
#include <linux/backing-dev.h>
#include <linux/fs.h>
#include <linux/blktrace_api.h>
+#include <linux/pr.h>
#include <asm/uaccess.h>
static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user *arg)
@@ -295,6 +296,96 @@ int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode,
*/
EXPORT_SYMBOL_GPL(__blkdev_driver_ioctl);
+static int blkdev_pr_register(struct block_device *bdev,
+ struct pr_registration __user *arg)
+{
+ const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
+ struct pr_registration reg;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ if (!ops || !ops->pr_register)
+ return -EOPNOTSUPP;
+ if (copy_from_user(&reg, arg, sizeof(reg)))
+ return -EFAULT;
+
+ if (reg.flags & ~PR_FL_IGNORE_KEY)
+ return -EOPNOTSUPP;
+ return ops->pr_register(bdev, reg.old_key, reg.new_key, reg.flags);
+}
+
+static int blkdev_pr_reserve(struct block_device *bdev,
+ struct pr_reservation __user *arg)
+{
+ const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
+ struct pr_reservation rsv;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ if (!ops || !ops->pr_reserve)
+ return -EOPNOTSUPP;
+ if (copy_from_user(&rsv, arg, sizeof(rsv)))
+ return -EFAULT;
+
+ if (rsv.flags & ~PR_FL_IGNORE_KEY)
+ return -EOPNOTSUPP;
+ return ops->pr_reserve(bdev, rsv.key, rsv.type, rsv.flags);
+}
+
+static int blkdev_pr_release(struct block_device *bdev,
+ struct pr_reservation __user *arg)
+{
+ const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
+ struct pr_reservation rsv;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ if (!ops || !ops->pr_release)
+ return -EOPNOTSUPP;
+ if (copy_from_user(&rsv, arg, sizeof(rsv)))
+ return -EFAULT;
+
+ if (rsv.flags)
+ return -EOPNOTSUPP;
+ return ops->pr_release(bdev, rsv.key, rsv.type);
+}
+
+static int blkdev_pr_preempt(struct block_device *bdev,
+ struct pr_preempt __user *arg, bool abort)
+{
+ const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
+ struct pr_preempt p;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ if (!ops || !ops->pr_preempt)
+ return -EOPNOTSUPP;
+ if (copy_from_user(&p, arg, sizeof(p)))
+ return -EFAULT;
+
+ if (p.flags)
+ return -EOPNOTSUPP;
+ return ops->pr_preempt(bdev, p.old_key, p.new_key, p.type, abort);
+}
+
+static int blkdev_pr_clear(struct block_device *bdev,
+ struct pr_clear __user *arg)
+{
+ const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
+ struct pr_clear c;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ if (!ops || !ops->pr_clear)
+ return -EOPNOTSUPP;
+ if (copy_from_user(&c, arg, sizeof(c)))
+ return -EFAULT;
+
+ if (c.flags)
+ return -EOPNOTSUPP;
+ return ops->pr_clear(bdev, c.key);
+}
+
/*
* Is it an unrecognized ioctl? The correct returns are either
* ENOTTY (final) or ENOIOCTLCMD ("I don't know this one, try a
@@ -477,6 +568,18 @@ int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
case BLKTRACESETUP:
case BLKTRACETEARDOWN:
return blk_trace_ioctl(bdev, cmd, argp);
+ case IOC_PR_REGISTER:
+ return blkdev_pr_register(bdev, argp);
+ case IOC_PR_RESERVE:
+ return blkdev_pr_reserve(bdev, argp);
+ case IOC_PR_RELEASE:
+ return blkdev_pr_release(bdev, argp);
+ case IOC_PR_PREEMPT:
+ return blkdev_pr_preempt(bdev, argp, false);
+ case IOC_PR_PREEMPT_ABORT:
+ return blkdev_pr_preempt(bdev, argp, true);
+ case IOC_PR_CLEAR:
+ return blkdev_pr_clear(bdev, argp);
default:
return __blkdev_driver_ioctl(bdev, mode, cmd, arg);
}