d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Add v_inval_buf_range, like vtruncbuf but for a range of a file

Browse Source 
v_inval_buf_range invalidates all buffers within a certain LBA range of a
file. It will be used by fusefs(5). This commit is a partial merge of
r346162, r346606, and r346756 from projects/fuse2.

Reviewed by:	kib
MFC after:	2 weeks
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D21032
This commit is contained in:
Alan Somers 2019-07-28 00:48:28 +00:00
parent 1173e5a721
commit 2240d8c465
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=350386
2 changed files with 102 additions and 56 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

156
sys/kern/vfs_subr.c
View File

@ -118,6 +118,8 @@ static void vfs_knl_assert_locked(void *arg);
static void vfs_knl_assert_unlocked(void *arg);
static void vnlru_return_batches(struct vfsops *mnt_op);
static void destroy_vpollinfo(struct vpollinfo *vi);
static int v_inval_buf_range_locked(struct vnode *vp, struct bufobj *bo,
daddr_t startlbn, daddr_t endlbn);
/*
* These fences are intended for cases where some synchronization is
@ -1954,9 +1956,8 @@ int
vtruncbuf(struct vnode *vp, off_t length, int blksize)
{
struct buf *bp, *nbp;
int anyfreed;
daddr_t trunclbn;
struct bufobj *bo;
daddr_t startlbn;
CTR4(KTR_VFS, "%s: vp %p with block %d:%ju", __func__,
vp, blksize, (uintmax_t)length);
@ -1964,62 +1965,16 @@ vtruncbuf(struct vnode *vp, off_t length, int blksize)
/*
* Round up to the *next* lbn.
*/
trunclbn = howmany(length, blksize);
startlbn = howmany(length, blksize);
ASSERT_VOP_LOCKED(vp, "vtruncbuf");
restart:
bo = &vp->v_bufobj;
restart_unlocked:
BO_LOCK(bo);
anyfreed = 1;
for (;anyfreed;) {
anyfreed = 0;
TAILQ_FOREACH_SAFE(bp, &bo->bo_clean.bv_hd, b_bobufs, nbp) {
if (bp->b_lblkno < trunclbn)
continue;
if (BUF_LOCK(bp,
LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK,
BO_LOCKPTR(bo)) == ENOLCK)
goto restart;
bremfree(bp);
bp->b_flags |= (B_INVAL | B_RELBUF);
bp->b_flags &= ~B_ASYNC;
brelse(bp);
anyfreed = 1;
BO_LOCK(bo);
if (nbp != NULL &&
(((nbp->b_xflags & BX_VNCLEAN) == 0) ||
(nbp->b_vp != vp) ||
(nbp->b_flags & B_DELWRI))) {
BO_UNLOCK(bo);
goto restart;
}
}
TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
if (bp->b_lblkno < trunclbn)
continue;
if (BUF_LOCK(bp,
LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK,
BO_LOCKPTR(bo)) == ENOLCK)
goto restart;
bremfree(bp);
bp->b_flags |= (B_INVAL | B_RELBUF);
bp->b_flags &= ~B_ASYNC;
brelse(bp);
anyfreed = 1;
BO_LOCK(bo);
if (nbp != NULL &&
(((nbp->b_xflags & BX_VNDIRTY) == 0) ||
(nbp->b_vp != vp) ||
(nbp->b_flags & B_DELWRI) == 0)) {
BO_UNLOCK(bo);
goto restart;
}
}
}
while (v_inval_buf_range_locked(vp, bo, startlbn, INT64_MAX) == EAGAIN)
;
if (length > 0) {
restartsync:
@ -2032,9 +1987,9 @@ vtruncbuf(struct vnode *vp, off_t length, int blksize)
*/
if (BUF_LOCK(bp,
LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK,
BO_LOCKPTR(bo)) == ENOLCK) {
goto restart;
}
BO_LOCKPTR(bo)) == ENOLCK)
goto restart_unlocked;
VNASSERT((bp->b_flags & B_DELWRI), vp,
("buf(%p) on dirty queue without DELWRI", bp));
@ -2052,6 +2007,95 @@ vtruncbuf(struct vnode *vp, off_t length, int blksize)
return (0);
}
/*
* Invalidate the cached pages of a file's buffer within the range of block
* numbers [startlbn, endlbn).
*/
void
v_inval_buf_range(struct vnode *vp, daddr_t startlbn, daddr_t endlbn,
int blksize)
{
struct bufobj *bo;
off_t start, end;
ASSERT_VOP_LOCKED(vp, "v_inval_buf_range");
start = blksize * startlbn;
end = blksize * endlbn;
bo = &vp->v_bufobj;
BO_LOCK(bo);
MPASS(blksize == bo->bo_bsize);
while (v_inval_buf_range_locked(vp, bo, startlbn, endlbn) == EAGAIN)
;
BO_UNLOCK(bo);
vn_pages_remove(vp, OFF_TO_IDX(start), OFF_TO_IDX(end + PAGE_SIZE - 1));
}
static int
v_inval_buf_range_locked(struct vnode *vp, struct bufobj *bo,
daddr_t startlbn, daddr_t endlbn)
{
struct buf *bp, *nbp;
bool anyfreed;
ASSERT_VOP_LOCKED(vp, "v_inval_buf_range_locked");
ASSERT_BO_LOCKED(bo);
do {
anyfreed = false;
TAILQ_FOREACH_SAFE(bp, &bo->bo_clean.bv_hd, b_bobufs, nbp) {
if (bp->b_lblkno < startlbn || bp->b_lblkno >= endlbn)
continue;
if (BUF_LOCK(bp,
LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK,
BO_LOCKPTR(bo)) == ENOLCK) {
BO_LOCK(bo);
return (EAGAIN);
}
bremfree(bp);
bp->b_flags |= B_INVAL | B_RELBUF;
bp->b_flags &= ~B_ASYNC;
brelse(bp);
anyfreed = true;
BO_LOCK(bo);
if (nbp != NULL &&
(((nbp->b_xflags & BX_VNCLEAN) == 0) ||
nbp->b_vp != vp ||
(nbp->b_flags & B_DELWRI) != 0))
return (EAGAIN);
}
TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
if (bp->b_lblkno < startlbn || bp->b_lblkno >= endlbn)
continue;
if (BUF_LOCK(bp,
LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK,
BO_LOCKPTR(bo)) == ENOLCK) {
BO_LOCK(bo);
return (EAGAIN);
}
bremfree(bp);
bp->b_flags |= B_INVAL | B_RELBUF;
bp->b_flags &= ~B_ASYNC;
brelse(bp);
anyfreed = true;
BO_LOCK(bo);
if (nbp != NULL &&
(((nbp->b_xflags & BX_VNDIRTY) == 0) ||
(nbp->b_vp != vp) ||
(nbp->b_flags & B_DELWRI) == 0))
return (EAGAIN);
}
} while (anyfreed);
return (0);
}
static void
buf_vlist_remove(struct buf *bp)
{

2
sys/sys/vnode.h
View File

@ -659,6 +659,8 @@ void _vhold(struct vnode *, bool);
void vinactive(struct vnode *, struct thread *);
int vinvalbuf(struct vnode *vp, int save, int slpflag, int slptimeo);
int vtruncbuf(struct vnode *vp, off_t length, int blksize);
void v_inval_buf_range(struct vnode *vp, daddr_t startlbn, daddr_t endlbn,
int blksize);
void vunref(struct vnode *);
void vn_printf(struct vnode *vp, const char *fmt, ...) __printflike(2,3);
int vrecycle(struct vnode *vp);