Author: asomers Date: Sun Jul 28 00:48:28 2019 New Revision: 350386 URL: https://svnweb.freebsd.org/changeset/base/350386
Log: Add v_inval_buf_range, like vtruncbuf but for a range of a file 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 Modified: head/sys/kern/vfs_subr.c head/sys/sys/vnode.h Modified: head/sys/kern/vfs_subr.c ============================================================================== --- head/sys/kern/vfs_subr.c Sat Jul 27 19:29:28 2019 (r350385) +++ head/sys/kern/vfs_subr.c Sun Jul 28 00:48:28 2019 (r350386) @@ -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); @@ -1964,91 +1965,134 @@ 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) + + while (v_inval_buf_range_locked(vp, bo, startlbn, INT64_MAX) == EAGAIN) + ; + + if (length > 0) { +restartsync: + TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { + if (bp->b_lblkno > 0) continue; + /* + * Since we hold the vnode lock this should only + * fail if we're racing with the buf daemon. + */ if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, BO_LOCKPTR(bo)) == ENOLCK) - goto restart; + goto restart_unlocked; - bremfree(bp); - bp->b_flags |= (B_INVAL | B_RELBUF); - bp->b_flags &= ~B_ASYNC; - brelse(bp); - anyfreed = 1; + VNASSERT((bp->b_flags & B_DELWRI), vp, + ("buf(%p) on dirty queue without DELWRI", bp)); + bremfree(bp); + bawrite(bp); 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; - } + goto restartsync; } + } - TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { - if (bp->b_lblkno < trunclbn) + bufobj_wwait(bo, 0, 0); + BO_UNLOCK(bo); + vnode_pager_setsize(vp, length); + + 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) - goto restart; + BO_LOCKPTR(bo)) == ENOLCK) { + BO_LOCK(bo); + return (EAGAIN); + } + bremfree(bp); - bp->b_flags |= (B_INVAL | B_RELBUF); + bp->b_flags |= B_INVAL | B_RELBUF; bp->b_flags &= ~B_ASYNC; brelse(bp); - anyfreed = 1; + anyfreed = true; 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; - } + (((nbp->b_xflags & BX_VNCLEAN) == 0) || + nbp->b_vp != vp || + (nbp->b_flags & B_DELWRI) != 0)) + return (EAGAIN); } - } - if (length > 0) { -restartsync: TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { - if (bp->b_lblkno > 0) + if (bp->b_lblkno < startlbn || bp->b_lblkno >= endlbn) continue; - /* - * Since we hold the vnode lock this should only - * fail if we're racing with the buf daemon. - */ if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, BO_LOCKPTR(bo)) == ENOLCK) { - goto restart; + BO_LOCK(bo); + return (EAGAIN); } - VNASSERT((bp->b_flags & B_DELWRI), vp, - ("buf(%p) on dirty queue without DELWRI", bp)); - bremfree(bp); - bawrite(bp); + bp->b_flags |= B_INVAL | B_RELBUF; + bp->b_flags &= ~B_ASYNC; + brelse(bp); + anyfreed = true; + BO_LOCK(bo); - goto restartsync; + if (nbp != NULL && + (((nbp->b_xflags & BX_VNDIRTY) == 0) || + (nbp->b_vp != vp) || + (nbp->b_flags & B_DELWRI) == 0)) + return (EAGAIN); } - } - - bufobj_wwait(bo, 0, 0); - BO_UNLOCK(bo); - vnode_pager_setsize(vp, length); - + } while (anyfreed); return (0); } Modified: head/sys/sys/vnode.h ============================================================================== --- head/sys/sys/vnode.h Sat Jul 27 19:29:28 2019 (r350385) +++ head/sys/sys/vnode.h Sun Jul 28 00:48:28 2019 (r350386) @@ -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); _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
