c/mirror_zfs
1
0
Fork 0
mirror of https://git.proxmox.com/git/mirror_zfs.git synced 2024-11-17 01:51:00 +03:00
Code Issues Packages Projects Releases Wiki Activity

Avoid taking global lock to destroy zfsdev state

Browse Source 
We have exclusive access to our zfsdev state object in this section
until it is invalidated by setting zs_minor to -1, so we can destroy
the state without taking a lock if we do the invalidation last, after
a member to ensure correct ordering.

While here, strengthen the assertions that zs_minor is valid when we
enter.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Ryan Moeller <freqlabs@FreeBSD.org>
Closes #11751
This commit is contained in:
Ryan Moeller 2021-04-02 14:09:05 -04:00 committed by GitHub
parent 02aaf11fc7
commit dce3176349
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
2 changed files with 11 additions and 21 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
module/os/freebsd/zfs/kmod_core.c
View File

@ -185,18 +185,14 @@ zfsdev_close(void *data)
zfsdev_state_t *zs = data;
ASSERT(zs != NULL);
ASSERT3S(zs->zs_minor, >, 0);
mutex_enter(&zfsdev_state_lock);
ASSERT(zs->zs_minor != 0);
zs->zs_minor = -1;
zfs_onexit_destroy(zs->zs_onexit);
zfs_zevent_destroy(zs->zs_zevent);
zs->zs_onexit = NULL;
zs->zs_zevent = NULL;
mutex_exit(&zfsdev_state_lock);
membar_producer();
zs->zs_minor = -1;
}
static int

22
module/os/linux/zfs/zfs_ioctl_os.c
View File

@ -136,22 +136,20 @@ zfsdev_state_init(struct file *filp)
return (0);
}
static int
static void
zfsdev_state_destroy(struct file *filp)
{
zfsdev_state_t *zs;
zfsdev_state_t *zs = filp->private_data;
ASSERT(MUTEX_HELD(&zfsdev_state_lock));
ASSERT(filp->private_data != NULL);
ASSERT(zs != NULL);
ASSERT3S(zs->zs_minor, >, 0);
zs = filp->private_data;
zs->zs_minor = -1;
zfs_onexit_destroy(zs->zs_onexit);
zfs_zevent_destroy(zs->zs_zevent);
zs->zs_onexit = NULL;
zs->zs_zevent = NULL;
return (0);
membar_producer();
zs->zs_minor = -1;
}
static int
@ -169,13 +167,9 @@ zfsdev_open(struct inode *ino, struct file *filp)
static int
zfsdev_release(struct inode *ino, struct file *filp)
{
int error;
zfsdev_state_destroy(filp);
mutex_enter(&zfsdev_state_lock);
error = zfsdev_state_destroy(filp);
mutex_exit(&zfsdev_state_lock);
return (-error);
return (0);
}
static long