diff options
Diffstat (limited to 'sys/kern/vfs_default.c')
| -rw-r--r-- | sys/kern/vfs_default.c | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/sys/kern/vfs_default.c b/sys/kern/vfs_default.c index b89d990..e9f8151 100644 --- a/sys/kern/vfs_default.c +++ b/sys/kern/vfs_default.c @@ -96,6 +96,7 @@ struct vop_vector default_vnodeops = { .vop_access = vop_stdaccess, .vop_accessx = vop_stdaccessx, + .vop_advise = vop_stdadvise, .vop_advlock = vop_stdadvlock, .vop_advlockasync = vop_stdadvlockasync, .vop_advlockpurge = vop_stdadvlockpurge, @@ -984,6 +985,58 @@ vop_stdallocate(struct vop_allocate_args *ap) return (error); } +int +vop_stdadvise(struct vop_advise_args *ap) +{ + struct vnode *vp; + off_t start, end; + int error, vfslocked; + + vp = ap->a_vp; + switch (ap->a_advice) { + case POSIX_FADV_WILLNEED: + /* + * Do nothing for now. Filesystems should provide a + * custom method which starts an asynchronous read of + * the requested region. + */ + error = 0; + break; + case POSIX_FADV_DONTNEED: + /* + * Flush any open FS buffers and then remove pages + * from the backing VM object. Using vinvalbuf() here + * is a bit heavy-handed as it flushes all buffers for + * the given vnode, not just the buffers covering the + * requested range. + */ + error = 0; + vfslocked = VFS_LOCK_GIANT(vp->v_mount); + vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); + if (vp->v_iflag & VI_DOOMED) { + VOP_UNLOCK(vp, 0); + VFS_UNLOCK_GIANT(vfslocked); + break; + } + vinvalbuf(vp, V_CLEANONLY, 0, 0); + if (vp->v_object != NULL) { + start = trunc_page(ap->a_start); + end = round_page(ap->a_end); + VM_OBJECT_LOCK(vp->v_object); + vm_object_page_cache(vp->v_object, OFF_TO_IDX(start), + OFF_TO_IDX(end)); + VM_OBJECT_UNLOCK(vp->v_object); + } + VOP_UNLOCK(vp, 0); + VFS_UNLOCK_GIANT(vfslocked); + break; + default: + error = EINVAL; + break; + } + return (error); +} + /* * vfs default ops * used to fill the vfs function table to get reasonable default return values. |
