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| author | Konstantin Belousov <kib@FreeBSD.org> | 2022-12-28 18:13:01 +0000 |
|---|---|---|
| committer | Konstantin Belousov <kib@FreeBSD.org> | 2022-12-29 20:55:39 +0000 |
| commit | 37b9fb169686e867987c8a1a9868f81137b9df2b (patch) | |
| tree | 254d1aa0bc05e70c725033de0baf1560b155b1f8 /sys/kern/kern_descrip.c | |
| parent | 4ac8f4067096a9d4a00e41cd53bd5c4fa295fd15 (diff) | |
| download | src-37b9fb169686e867987c8a1a9868f81137b9df2b.tar.gz src-37b9fb169686e867987c8a1a9868f81137b9df2b.zip | |
Add descrip_check_write_mp() helper
... which verifies that given file table does not have file descriptors
referencing vnodes on the specified mount point. It is up to the caller
to ensure that the check is not racy.
Reviewed by: mckusick
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D37896
Diffstat (limited to 'sys/kern/kern_descrip.c')
| -rw-r--r-- | sys/kern/kern_descrip.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/sys/kern/kern_descrip.c b/sys/kern/kern_descrip.c index 63a7f8b2a6d7..0be59e930dd4 100644 --- a/sys/kern/kern_descrip.c +++ b/sys/kern/kern_descrip.c @@ -4172,6 +4172,29 @@ mountcheckdirs(struct vnode *olddp, struct vnode *newdp) vrele(olddp); } +int +descrip_check_write_mp(struct filedesc *fdp, struct mount *mp) +{ + struct file *fp; + struct vnode *vp; + int error, i; + + error = 0; + FILEDESC_SLOCK(fdp); + FILEDESC_FOREACH_FP(fdp, i, fp) { + if (fp->f_type != DTYPE_VNODE || + (atomic_load_int(&fp->f_flag) & FWRITE) == 0) + continue; + vp = fp->f_vnode; + if (vp->v_mount == mp) { + error = EDEADLK; + break; + } + } + FILEDESC_SUNLOCK(fdp); + return (error); +} + struct filedesc_to_leader * filedesc_to_leader_alloc(struct filedesc_to_leader *old, struct filedesc *fdp, struct proc *leader) |