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Index: head/sys/kern/vfs_bio.c
===================================================================
--- head/sys/kern/vfs_bio.c
+++ head/sys/kern/vfs_bio.c
@@ -154,7 +154,6 @@
/* Used below and for softdep flushing threads in ufs/ffs/ffs_softdep.c */
struct proc *bufdaemonproc;
-static int inmem(struct vnode *vp, daddr_t blkno);
static void vm_hold_free_pages(struct buf *bp, int newbsize);
static void vm_hold_load_pages(struct buf *bp, vm_offset_t from,
vm_offset_t to);
@@ -3585,48 +3584,54 @@
* associated VM object. This is like incore except
* it also hunts around in the VM system for the data.
*/
-
-static int
+bool
inmem(struct vnode * vp, daddr_t blkno)
{
vm_object_t obj;
vm_offset_t toff, tinc, size;
- vm_page_t m;
+ vm_page_t m, n;
vm_ooffset_t off;
+ int valid;
ASSERT_VOP_LOCKED(vp, "inmem");
if (incore(&vp->v_bufobj, blkno))
- return 1;
+ return (true);
if (vp->v_mount == NULL)
- return 0;
+ return (false);
obj = vp->v_object;
if (obj == NULL)
- return (0);
+ return (false);
size = PAGE_SIZE;
if (size > vp->v_mount->mnt_stat.f_iosize)
size = vp->v_mount->mnt_stat.f_iosize;
off = (vm_ooffset_t)blkno * (vm_ooffset_t)vp->v_mount->mnt_stat.f_iosize;
- VM_OBJECT_RLOCK(obj);
for (toff = 0; toff < vp->v_mount->mnt_stat.f_iosize; toff += tinc) {
- m = vm_page_lookup(obj, OFF_TO_IDX(off + toff));
- if (!m)
- goto notinmem;
+ m = vm_page_lookup_unlocked(obj, OFF_TO_IDX(off + toff));
+recheck:
+ if (m == NULL)
+ return (false);
+
tinc = size;
if (tinc > PAGE_SIZE - ((toff + off) & PAGE_MASK))
tinc = PAGE_SIZE - ((toff + off) & PAGE_MASK);
- if (vm_page_is_valid(m,
- (vm_offset_t) ((toff + off) & PAGE_MASK), tinc) == 0)
- goto notinmem;
+ /*
+ * Consider page validity only if page mapping didn't change
+ * during the check.
+ */
+ valid = vm_page_is_valid(m,
+ (vm_offset_t)((toff + off) & PAGE_MASK), tinc);
+ n = vm_page_lookup_unlocked(obj, OFF_TO_IDX(off + toff));
+ if (m != n) {
+ m = n;
+ goto recheck;
+ }
+ if (!valid)
+ return (false);
}
- VM_OBJECT_RUNLOCK(obj);
- return 1;
-
-notinmem:
- VM_OBJECT_RUNLOCK(obj);
- return (0);
+ return (true);
}
/*
Index: head/sys/sys/buf.h
===================================================================
--- head/sys/sys/buf.h
+++ head/sys/sys/buf.h
@@ -549,6 +549,7 @@
void vfs_busy_pages_acquire(struct buf *bp);
void vfs_busy_pages_release(struct buf *bp);
struct buf *incore(struct bufobj *, daddr_t);
+bool inmem(struct vnode *, daddr_t);
struct buf *gbincore(struct bufobj *, daddr_t);
struct buf *gbincore_unlocked(struct bufobj *, daddr_t);
struct buf *getblk(struct vnode *, daddr_t, int, int, int, int);
Index: head/sys/vm/vm_page.h
===================================================================
--- head/sys/vm/vm_page.h
+++ head/sys/vm/vm_page.h
@@ -700,6 +700,7 @@
void vm_page_invalid(vm_page_t m);
void vm_page_launder(vm_page_t m);
vm_page_t vm_page_lookup(vm_object_t, vm_pindex_t);
+vm_page_t vm_page_lookup_unlocked(vm_object_t, vm_pindex_t);
vm_page_t vm_page_next(vm_page_t m);
void vm_page_pqbatch_drain(void);
void vm_page_pqbatch_submit(vm_page_t m, uint8_t queue);
Index: head/sys/vm/vm_page.c
===================================================================
--- head/sys/vm/vm_page.c
+++ head/sys/vm/vm_page.c
@@ -1698,6 +1698,21 @@
}
/*
+ * vm_page_lookup_unlocked:
+ *
+ * Returns the page associated with the object/offset pair specified;
+ * if none is found, NULL is returned. The page may be no longer be
+ * present in the object at the time that this function returns. Only
+ * useful for opportunistic checks such as inmem().
+ */
+vm_page_t
+vm_page_lookup_unlocked(vm_object_t object, vm_pindex_t pindex)
+{
+
+ return (vm_radix_lookup_unlocked(&object->rtree, pindex));
+}
+
+/*
* vm_page_relookup:
*
* Returns a page that must already have been busied by

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