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Index: head/sys/vm/vm_fault.c
===================================================================
--- head/sys/vm/vm_fault.c
+++ head/sys/vm/vm_fault.c
@@ -628,19 +628,62 @@
return (result);
}
+static int
+vm_fault_lock_vnode(struct faultstate *fs)
+{
+ struct vnode *vp;
+ int error, locked;
+
+ if (fs->object->type != OBJT_VNODE)
+ return (KERN_SUCCESS);
+ vp = fs->object->handle;
+ if (vp == fs->vp)
+ return (KERN_SUCCESS);
+
+ /*
+ * Perform an unlock in case the desired vnode changed while
+ * the map was unlocked during a retry.
+ */
+ unlock_vp(fs);
+
+ locked = VOP_ISLOCKED(vp);
+ if (locked != LK_EXCLUSIVE)
+ locked = LK_SHARED;
+
+ /*
+ * We must not sleep acquiring the vnode lock while we have
+ * the page exclusive busied or the object's
+ * paging-in-progress count incremented. Otherwise, we could
+ * deadlock.
+ */
+ error = vget(vp, locked | LK_CANRECURSE | LK_NOWAIT, curthread);
+ if (error == 0) {
+ fs->vp = vp;
+ return (KERN_SUCCESS);
+ }
+
+ vhold(vp);
+ release_page(fs);
+ unlock_and_deallocate(fs);
+ error = vget(vp, locked | LK_RETRY | LK_CANRECURSE, curthread);
+ vdrop(vp);
+ fs->vp = vp;
+ KASSERT(error == 0, ("vm_fault: vget failed %d", error));
+ return (KERN_RESOURCE_SHORTAGE);
+}
+
int
vm_fault(vm_map_t map, vm_offset_t vaddr, vm_prot_t fault_type,
int fault_flags, vm_page_t *m_hold)
{
struct faultstate fs;
- struct vnode *vp;
struct domainset *dset;
vm_object_t next_object, retry_object;
vm_offset_t e_end, e_start;
vm_pindex_t retry_pindex;
vm_prot_t prot, retry_prot;
- int ahead, alloc_req, behind, cluster_offset, error, era, faultcount;
- int locked, nera, oom, result, rv;
+ int ahead, alloc_req, behind, cluster_offset, era, faultcount;
+ int nera, oom, result, rv;
u_char behavior;
boolean_t wired; /* Passed by reference. */
bool dead, hardfault, is_first_object_locked;
@@ -1001,41 +1044,11 @@
*/
unlock_map(&fs);
- if (fs.object->type == OBJT_VNODE &&
- (vp = fs.object->handle) != fs.vp) {
- /*
- * Perform an unlock in case the desired vnode
- * changed while the map was unlocked during a
- * retry.
- */
- unlock_vp(&fs);
-
- locked = VOP_ISLOCKED(vp);
- if (locked != LK_EXCLUSIVE)
- locked = LK_SHARED;
-
- /*
- * We must not sleep acquiring the vnode lock
- * while we have the page exclusive busied or
- * the object's paging-in-progress count
- * incremented. Otherwise, we could deadlock.
- */
- error = vget(vp, locked | LK_CANRECURSE |
- LK_NOWAIT, curthread);
- if (error != 0) {
- vhold(vp);
- release_page(&fs);
- unlock_and_deallocate(&fs);
- error = vget(vp, locked | LK_RETRY |
- LK_CANRECURSE, curthread);
- vdrop(vp);
- fs.vp = vp;
- KASSERT(error == 0,
- ("vm_fault: vget failed"));
- goto RetryFault;
- }
- fs.vp = vp;
- }
+ rv = vm_fault_lock_vnode(&fs);
+ MPASS(rv == KERN_SUCCESS ||
+ rv == KERN_RESOURCE_SHORTAGE);
+ if (rv == KERN_RESOURCE_SHORTAGE)
+ goto RetryFault;
KASSERT(fs.vp == NULL || !fs.map->system_map,
("vm_fault: vnode-backed object mapped by system map"));

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