int cluster_read_gb(struct vnode *vp, u_quad_t filesize, daddr_t lblkno, long size, struct ucred *cred, long totread, int seqcount, int gbflags, struct buf **bpp) { struct buf *bp, *rbp, *reqbp; struct bufobj *bo; daddr_t blkno, origblkno; int maxra, racluster; int error, ncontig; int i; error = 0; bo = &vp->v_bufobj; if (!unmapped_buf_allowed) gbflags &= ~GB_UNMAPPED; /* * Try to limit the amount of read-ahead by a few * ad-hoc parameters. This needs work!!! */ racluster = vp->v_mount->mnt_iosize_max / size; maxra = seqcount; maxra = min(read_max, maxra); maxra = min(nbuf/8, maxra); if (((u_quad_t)(lblkno + maxra + 1) * size) > filesize) maxra = (filesize / size) - lblkno; /* * get the requested block */ *bpp = reqbp = bp = getblk(vp, lblkno, size, 0, 0, gbflags); origblkno = lblkno; /* * if it is in the cache, then check to see if the reads have been * sequential. If they have, then try some read-ahead, otherwise * back-off on prospective read-aheads. */ if (bp->b_flags & B_CACHE) { if (!seqcount) { return 0; } else if ((bp->b_flags & B_RAM) == 0) { return 0; } else { bp->b_flags &= ~B_RAM; BO_LOCK(bo); for (i = 1; i < maxra; i++) { /* * Stop if the buffer does not exist or it * is invalid (about to go away?) */ rbp = gbincore(&vp->v_bufobj, lblkno+i); if (rbp == NULL || (rbp->b_flags & B_INVAL)) break; /* * Set another read-ahead mark so we know * to check again. (If we can lock the * buffer without waiting) */ if ((((i % racluster) == (racluster - 1)) || (i == (maxra - 1))) && (0 == BUF_LOCK(rbp, LK_EXCLUSIVE | LK_NOWAIT, NULL))) { rbp->b_flags |= B_RAM; BUF_UNLOCK(rbp); } } BO_UNLOCK(bo); if (i >= maxra) { return 0; } lblkno += i; } reqbp = bp = NULL; /* * If it isn't in the cache, then get a chunk from * disk if sequential, otherwise just get the block. */ } else { off_t firstread = bp->b_offset; int nblks; long minread; KASSERT(bp->b_offset != NOOFFSET, ("cluster_read: no buffer offset")); ncontig = 0; /* * Adjust totread if needed */ minread = read_min * size; if (minread > totread) totread = minread; /* * Compute the total number of blocks that we should read * synchronously. */ if (firstread + totread > filesize) totread = filesize - firstread; nblks = howmany(totread, size); if (nblks > racluster) nblks = racluster; /* * Now compute the number of contiguous blocks. */ if (nblks > 1) { error = VOP_BMAP(vp, lblkno, NULL, &blkno, &ncontig, NULL); /* * If this failed to map just do the original block. */ if (error || blkno == -1) ncontig = 0; } /* * If we have contiguous data available do a cluster * otherwise just read the requested block. */ if (ncontig) { /* Account for our first block. */ ncontig = min(ncontig + 1, nblks); if (ncontig < nblks) nblks = ncontig; bp = cluster_rbuild(vp, filesize, lblkno, blkno, size, nblks, gbflags, bp); lblkno += (bp->b_bufsize / size); } else { bp->b_flags |= B_RAM; bp->b_iocmd = BIO_READ; lblkno += 1; } } /* * handle the synchronous read so that it is available ASAP. */ if (bp) { if ((bp->b_flags & B_CLUSTER) == 0) { vfs_busy_pages(bp, 0); } bp->b_flags &= ~B_INVAL; bp->b_ioflags &= ~BIO_ERROR; if ((bp->b_flags & B_ASYNC) || bp->b_iodone != NULL) BUF_KERNPROC(bp); bp->b_iooffset = dbtob(bp->b_blkno); bstrategy(bp); curthread->td_ru.ru_inblock++; } /* * If we have been doing sequential I/O, then do some read-ahead. */ while (lblkno < (origblkno + maxra)) { error = VOP_BMAP(vp, lblkno, NULL, &blkno, &ncontig, NULL); if (error) break; if (blkno == -1) break; /* * We could throttle ncontig here by maxra but we might as * well read the data if it is contiguous. We're throttled * by racluster anyway. */ if (ncontig) { ncontig = min(ncontig + 1, racluster); rbp = cluster_rbuild(vp, filesize, lblkno, blkno, size, ncontig, gbflags, NULL); lblkno += (rbp->b_bufsize / size); if (rbp->b_flags & B_DELWRI) { bqrelse(rbp); continue; } } else { rbp = getblk(vp, lblkno, size, 0, 0, gbflags); lblkno += 1; if (rbp->b_flags & B_DELWRI) { bqrelse(rbp); continue; } rbp->b_flags |= B_ASYNC | B_RAM; rbp->b_iocmd = BIO_READ; rbp->b_blkno = blkno; } if (rbp->b_flags & B_CACHE) { rbp->b_flags &= ~B_ASYNC; bqrelse(rbp); continue; } if ((rbp->b_flags & B_CLUSTER) == 0) { vfs_busy_pages(rbp, 0); } rbp->b_flags &= ~B_INVAL; rbp->b_ioflags &= ~BIO_ERROR; if ((rbp->b_flags & B_ASYNC) || rbp->b_iodone != NULL) BUF_KERNPROC(rbp); rbp->b_iooffset = dbtob(rbp->b_blkno); bstrategy(rbp); curthread->td_ru.ru_inblock++; } if (reqbp) return (bufwait(reqbp)); else return (error); }
/* * If blocks are contiguous on disk, use this to provide clustered * read ahead. We will read as many blocks as possible sequentially * and then parcel them up into logical blocks in the buffer hash table. */ static struct buf * cluster_rbuild(struct vnode *vp, u_quad_t filesize, daddr_t lbn, daddr_t blkno, long size, int run, int gbflags, struct buf *fbp) { struct bufobj *bo; struct buf *bp, *tbp; daddr_t bn; off_t off; long tinc, tsize; int i, inc, j, toff; KASSERT(size == vp->v_mount->mnt_stat.f_iosize, ("cluster_rbuild: size %ld != filesize %jd\n", size, (intmax_t)vp->v_mount->mnt_stat.f_iosize)); /* * avoid a division */ while ((u_quad_t) size * (lbn + run) > filesize) { --run; } if (fbp) { tbp = fbp; tbp->b_iocmd = BIO_READ; } else { tbp = getblk(vp, lbn, size, 0, 0, gbflags); if (tbp->b_flags & B_CACHE) return tbp; tbp->b_flags |= B_ASYNC | B_RAM; tbp->b_iocmd = BIO_READ; } tbp->b_blkno = blkno; if( (tbp->b_flags & B_MALLOC) || ((tbp->b_flags & B_VMIO) == 0) || (run <= 1) ) return tbp; bp = trypbuf(&cluster_pbuf_freecnt); if (bp == 0) return tbp; /* * We are synthesizing a buffer out of vm_page_t's, but * if the block size is not page aligned then the starting * address may not be either. Inherit the b_data offset * from the original buffer. */ bp->b_flags = B_ASYNC | B_CLUSTER | B_VMIO; if ((gbflags & GB_UNMAPPED) != 0) { bp->b_flags |= B_UNMAPPED; bp->b_data = unmapped_buf; } else { bp->b_data = (char *)((vm_offset_t)bp->b_data | ((vm_offset_t)tbp->b_data & PAGE_MASK)); } bp->b_iocmd = BIO_READ; bp->b_iodone = cluster_callback; bp->b_blkno = blkno; bp->b_lblkno = lbn; bp->b_offset = tbp->b_offset; KASSERT(bp->b_offset != NOOFFSET, ("cluster_rbuild: no buffer offset")); pbgetvp(vp, bp); TAILQ_INIT(&bp->b_cluster.cluster_head); bp->b_bcount = 0; bp->b_bufsize = 0; bp->b_npages = 0; inc = btodb(size); bo = &vp->v_bufobj; for (bn = blkno, i = 0; i < run; ++i, bn += inc) { if (i != 0) { if ((bp->b_npages * PAGE_SIZE) + round_page(size) > vp->v_mount->mnt_iosize_max) { break; } tbp = getblk(vp, lbn + i, size, 0, 0, GB_LOCK_NOWAIT | (gbflags & GB_UNMAPPED)); /* Don't wait around for locked bufs. */ if (tbp == NULL) break; /* * Stop scanning if the buffer is fully valid * (marked B_CACHE), or locked (may be doing a * background write), or if the buffer is not * VMIO backed. The clustering code can only deal * with VMIO-backed buffers. */ BO_LOCK(bo); if ((tbp->b_vflags & BV_BKGRDINPROG) || (tbp->b_flags & B_CACHE) || (tbp->b_flags & B_VMIO) == 0) { BO_UNLOCK(bo); bqrelse(tbp); break; } BO_UNLOCK(bo); /* * The buffer must be completely invalid in order to * take part in the cluster. If it is partially valid * then we stop. */ off = tbp->b_offset; tsize = size; VM_OBJECT_LOCK(tbp->b_bufobj->bo_object); for (j = 0; tsize > 0; j++) { toff = off & PAGE_MASK; tinc = tsize; if (toff + tinc > PAGE_SIZE) tinc = PAGE_SIZE - toff; VM_OBJECT_LOCK_ASSERT(tbp->b_pages[j]->object, MA_OWNED); if ((tbp->b_pages[j]->valid & vm_page_bits(toff, tinc)) != 0) break; off += tinc; tsize -= tinc; } VM_OBJECT_UNLOCK(tbp->b_bufobj->bo_object); if (tsize > 0) { bqrelse(tbp); break; } /* * Set a read-ahead mark as appropriate */ if ((fbp && (i == 1)) || (i == (run - 1))) tbp->b_flags |= B_RAM; /* * Set the buffer up for an async read (XXX should * we do this only if we do not wind up brelse()ing?). * Set the block number if it isn't set, otherwise * if it is make sure it matches the block number we * expect. */ tbp->b_flags |= B_ASYNC; tbp->b_iocmd = BIO_READ; if (tbp->b_blkno == tbp->b_lblkno) { tbp->b_blkno = bn; } else if (tbp->b_blkno != bn) { brelse(tbp); break; } } /* * XXX fbp from caller may not be B_ASYNC, but we are going * to biodone() it in cluster_callback() anyway */ BUF_KERNPROC(tbp); TAILQ_INSERT_TAIL(&bp->b_cluster.cluster_head, tbp, b_cluster.cluster_entry); VM_OBJECT_LOCK(tbp->b_bufobj->bo_object); for (j = 0; j < tbp->b_npages; j += 1) { vm_page_t m; m = tbp->b_pages[j]; vm_page_io_start(m); vm_object_pip_add(m->object, 1); if ((bp->b_npages == 0) || (bp->b_pages[bp->b_npages-1] != m)) { bp->b_pages[bp->b_npages] = m; bp->b_npages++; } if (m->valid == VM_PAGE_BITS_ALL) tbp->b_pages[j] = bogus_page; } VM_OBJECT_UNLOCK(tbp->b_bufobj->bo_object); /* * Don't inherit tbp->b_bufsize as it may be larger due to * a non-page-aligned size. Instead just aggregate using * 'size'. */ if (tbp->b_bcount != size) printf("warning: tbp->b_bcount wrong %ld vs %ld\n", tbp->b_bcount, size); if (tbp->b_bufsize != size) printf("warning: tbp->b_bufsize wrong %ld vs %ld\n", tbp->b_bufsize, size); bp->b_bcount += size; bp->b_bufsize += size; } /* * Fully valid pages in the cluster are already good and do not need * to be re-read from disk. Replace the page with bogus_page */ VM_OBJECT_LOCK(bp->b_bufobj->bo_object); for (j = 0; j < bp->b_npages; j++) { VM_OBJECT_LOCK_ASSERT(bp->b_pages[j]->object, MA_OWNED); if (bp->b_pages[j]->valid == VM_PAGE_BITS_ALL) bp->b_pages[j] = bogus_page; } VM_OBJECT_UNLOCK(bp->b_bufobj->bo_object); if (bp->b_bufsize > bp->b_kvasize) panic("cluster_rbuild: b_bufsize(%ld) > b_kvasize(%d)\n", bp->b_bufsize, bp->b_kvasize); bp->b_kvasize = bp->b_bufsize; if ((bp->b_flags & B_UNMAPPED) == 0) { pmap_qenter(trunc_page((vm_offset_t) bp->b_data), (vm_page_t *)bp->b_pages, bp->b_npages); } return (bp); }
/* * Truncate the inode oip to at most length size, freeing the * disk blocks. */ int ext2_truncate(struct vnode *vp, off_t length, int flags, struct ucred *cred, struct thread *td) { struct vnode *ovp = vp; int32_t lastblock; struct inode *oip; int32_t bn, lbn, lastiblock[NIADDR], indir_lbn[NIADDR]; uint32_t oldblks[NDADDR + NIADDR], newblks[NDADDR + NIADDR]; struct m_ext2fs *fs; struct buf *bp; int offset, size, level; e4fs_daddr_t count, nblocks, blocksreleased = 0; int error, i, allerror; off_t osize; #ifdef INVARIANTS struct bufobj *bo; #endif oip = VTOI(ovp); #ifdef INVARIANTS bo = &ovp->v_bufobj; #endif ASSERT_VOP_LOCKED(vp, "ext2_truncate"); if (length < 0) return (EINVAL); if (ovp->v_type == VLNK && oip->i_size < ovp->v_mount->mnt_maxsymlinklen) { #ifdef INVARIANTS if (length != 0) panic("ext2_truncate: partial truncate of symlink"); #endif bzero((char *)&oip->i_shortlink, (u_int)oip->i_size); oip->i_size = 0; oip->i_flag |= IN_CHANGE | IN_UPDATE; return (ext2_update(ovp, 1)); } if (oip->i_size == length) { oip->i_flag |= IN_CHANGE | IN_UPDATE; return (ext2_update(ovp, 0)); } fs = oip->i_e2fs; osize = oip->i_size; /* * Lengthen the size of the file. We must ensure that the * last byte of the file is allocated. Since the smallest * value of osize is 0, length will be at least 1. */ if (osize < length) { if (length > oip->i_e2fs->e2fs_maxfilesize) return (EFBIG); vnode_pager_setsize(ovp, length); offset = blkoff(fs, length - 1); lbn = lblkno(fs, length - 1); flags |= BA_CLRBUF; error = ext2_balloc(oip, lbn, offset + 1, cred, &bp, flags); if (error) { vnode_pager_setsize(vp, osize); return (error); } oip->i_size = length; if (bp->b_bufsize == fs->e2fs_bsize) bp->b_flags |= B_CLUSTEROK; if (flags & IO_SYNC) bwrite(bp); else if (DOINGASYNC(ovp)) bdwrite(bp); else bawrite(bp); oip->i_flag |= IN_CHANGE | IN_UPDATE; return (ext2_update(ovp, !DOINGASYNC(ovp))); } /* * Shorten the size of the file. If the file is not being * truncated to a block boundry, the contents of the * partial block following the end of the file must be * zero'ed in case it ever become accessible again because * of subsequent file growth. */ /* I don't understand the comment above */ offset = blkoff(fs, length); if (offset == 0) { oip->i_size = length; } else { lbn = lblkno(fs, length); flags |= BA_CLRBUF; error = ext2_balloc(oip, lbn, offset, cred, &bp, flags); if (error) return (error); oip->i_size = length; size = blksize(fs, oip, lbn); bzero((char *)bp->b_data + offset, (u_int)(size - offset)); allocbuf(bp, size); if (bp->b_bufsize == fs->e2fs_bsize) bp->b_flags |= B_CLUSTEROK; if (flags & IO_SYNC) bwrite(bp); else if (DOINGASYNC(ovp)) bdwrite(bp); else bawrite(bp); } /* * Calculate index into inode's block list of * last direct and indirect blocks (if any) * which we want to keep. Lastblock is -1 when * the file is truncated to 0. */ lastblock = lblkno(fs, length + fs->e2fs_bsize - 1) - 1; lastiblock[SINGLE] = lastblock - NDADDR; lastiblock[DOUBLE] = lastiblock[SINGLE] - NINDIR(fs); lastiblock[TRIPLE] = lastiblock[DOUBLE] - NINDIR(fs) * NINDIR(fs); nblocks = btodb(fs->e2fs_bsize); /* * Update file and block pointers on disk before we start freeing * blocks. If we crash before free'ing blocks below, the blocks * will be returned to the free list. lastiblock values are also * normalized to -1 for calls to ext2_indirtrunc below. */ for (level = TRIPLE; level >= SINGLE; level--) { oldblks[NDADDR + level] = oip->i_ib[level]; if (lastiblock[level] < 0) { oip->i_ib[level] = 0; lastiblock[level] = -1; } } for (i = 0; i < NDADDR; i++) { oldblks[i] = oip->i_db[i]; if (i > lastblock) oip->i_db[i] = 0; } oip->i_flag |= IN_CHANGE | IN_UPDATE; allerror = ext2_update(ovp, !DOINGASYNC(ovp)); /* * Having written the new inode to disk, save its new configuration * and put back the old block pointers long enough to process them. * Note that we save the new block configuration so we can check it * when we are done. */ for (i = 0; i < NDADDR; i++) { newblks[i] = oip->i_db[i]; oip->i_db[i] = oldblks[i]; } for (i = 0; i < NIADDR; i++) { newblks[NDADDR + i] = oip->i_ib[i]; oip->i_ib[i] = oldblks[NDADDR + i]; } oip->i_size = osize; error = vtruncbuf(ovp, cred, length, (int)fs->e2fs_bsize); if (error && (allerror == 0)) allerror = error; vnode_pager_setsize(ovp, length); /* * Indirect blocks first. */ indir_lbn[SINGLE] = -NDADDR; indir_lbn[DOUBLE] = indir_lbn[SINGLE] - NINDIR(fs) - 1; indir_lbn[TRIPLE] = indir_lbn[DOUBLE] - NINDIR(fs) * NINDIR(fs) - 1; for (level = TRIPLE; level >= SINGLE; level--) { bn = oip->i_ib[level]; if (bn != 0) { error = ext2_indirtrunc(oip, indir_lbn[level], fsbtodb(fs, bn), lastiblock[level], level, &count); if (error) allerror = error; blocksreleased += count; if (lastiblock[level] < 0) { oip->i_ib[level] = 0; ext2_blkfree(oip, bn, fs->e2fs_fsize); blocksreleased += nblocks; } } if (lastiblock[level] >= 0) goto done; } /* * All whole direct blocks or frags. */ for (i = NDADDR - 1; i > lastblock; i--) { long bsize; bn = oip->i_db[i]; if (bn == 0) continue; oip->i_db[i] = 0; bsize = blksize(fs, oip, i); ext2_blkfree(oip, bn, bsize); blocksreleased += btodb(bsize); } if (lastblock < 0) goto done; /* * Finally, look for a change in size of the * last direct block; release any frags. */ bn = oip->i_db[lastblock]; if (bn != 0) { long oldspace, newspace; /* * Calculate amount of space we're giving * back as old block size minus new block size. */ oldspace = blksize(fs, oip, lastblock); oip->i_size = length; newspace = blksize(fs, oip, lastblock); if (newspace == 0) panic("ext2_truncate: newspace"); if (oldspace - newspace > 0) { /* * Block number of space to be free'd is * the old block # plus the number of frags * required for the storage we're keeping. */ bn += numfrags(fs, newspace); ext2_blkfree(oip, bn, oldspace - newspace); blocksreleased += btodb(oldspace - newspace); } } done: #ifdef INVARIANTS for (level = SINGLE; level <= TRIPLE; level++) if (newblks[NDADDR + level] != oip->i_ib[level]) panic("itrunc1"); for (i = 0; i < NDADDR; i++) if (newblks[i] != oip->i_db[i]) panic("itrunc2"); BO_LOCK(bo); if (length == 0 && (bo->bo_dirty.bv_cnt != 0 || bo->bo_clean.bv_cnt != 0)) panic("itrunc3"); BO_UNLOCK(bo); #endif /* INVARIANTS */ /* * Put back the real size. */ oip->i_size = length; if (oip->i_blocks >= blocksreleased) oip->i_blocks -= blocksreleased; else /* sanity */ oip->i_blocks = 0; oip->i_flag |= IN_CHANGE; vnode_pager_setsize(ovp, length); return (allerror); }
/* * Unmount the filesystem described by mp. */ static int msdosfs_unmount(struct mount *mp, int mntflags) { struct msdosfsmount *pmp; int error, flags; error = flags = 0; pmp = VFSTOMSDOSFS(mp); if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0) error = msdosfs_sync(mp, MNT_WAIT); if ((mntflags & MNT_FORCE) != 0) flags |= FORCECLOSE; else if (error != 0) return (error); error = vflush(mp, 0, flags, curthread); if (error != 0 && error != ENXIO) return (error); if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0) { error = markvoldirty(pmp, 0); if (error && error != ENXIO) { (void)markvoldirty(pmp, 1); return (error); } } if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) { if (pmp->pm_w2u) msdosfs_iconv->close(pmp->pm_w2u); if (pmp->pm_u2w) msdosfs_iconv->close(pmp->pm_u2w); if (pmp->pm_d2u) msdosfs_iconv->close(pmp->pm_d2u); if (pmp->pm_u2d) msdosfs_iconv->close(pmp->pm_u2d); } #ifdef MSDOSFS_DEBUG { struct vnode *vp = pmp->pm_devvp; struct bufobj *bo; bo = &vp->v_bufobj; BO_LOCK(bo); VI_LOCK(vp); vn_printf(vp, "msdosfs_umount(): just before calling VOP_CLOSE()\n"); printf("freef %p, freeb %p, mount %p\n", TAILQ_NEXT(vp, v_actfreelist), vp->v_actfreelist.tqe_prev, vp->v_mount); printf("cleanblkhd %p, dirtyblkhd %p, numoutput %ld, type %d\n", TAILQ_FIRST(&vp->v_bufobj.bo_clean.bv_hd), TAILQ_FIRST(&vp->v_bufobj.bo_dirty.bv_hd), vp->v_bufobj.bo_numoutput, vp->v_type); VI_UNLOCK(vp); BO_UNLOCK(bo); } #endif DROP_GIANT(); if (pmp->pm_devvp->v_type == VCHR && pmp->pm_devvp->v_rdev != NULL) pmp->pm_devvp->v_rdev->si_mountpt = NULL; g_topology_lock(); g_vfs_close(pmp->pm_cp); g_topology_unlock(); PICKUP_GIANT(); vrele(pmp->pm_devvp); dev_rel(pmp->pm_dev); free(pmp->pm_inusemap, M_MSDOSFSFAT); if (pmp->pm_flags & MSDOSFS_LARGEFS) msdosfs_fileno_free(mp); lockdestroy(&pmp->pm_fatlock); free(pmp, M_MSDOSFSMNT); mp->mnt_data = NULL; MNT_ILOCK(mp); mp->mnt_flag &= ~MNT_LOCAL; MNT_IUNLOCK(mp); return (error); }
/* * Truncate the inode ip to at most length size, freeing the * disk blocks. */ int ffs_truncate(vnode *vp, off_t length, int flags, Ucred *cred) { print("HARVEY TODO: %s\n", __func__); #if 0 struct inode *ip; ufs2_daddr_t bn, lbn, lastblock, lastiblock[UFS_NIADDR]; ufs2_daddr_t indir_lbn[UFS_NIADDR], oldblks[UFS_NDADDR + UFS_NIADDR]; ufs2_daddr_t newblks[UFS_NDADDR + UFS_NIADDR]; ufs2_daddr_t count, blocksreleased = 0, datablocks, blkno; struct bufobj *bo; struct fs *fs; struct buf *bp; struct ufsmount *ump; int softdeptrunc, journaltrunc; int needextclean, extblocks; int offset, size, level, nblocks; int i, error, allerror, indiroff, waitforupdate; off_t osize; ip = VTOI(vp); ump = VFSTOUFS(vp->v_mount); fs = ump->um_fs; bo = &vp->v_bufobj; ASSERT_VOP_LOCKED(vp, "ffs_truncate"); if (length < 0) return (EINVAL); if (length > fs->fs_maxfilesize) return (EFBIG); #ifdef QUOTA error = getinoquota(ip); if (error) return (error); #endif /* * Historically clients did not have to specify which data * they were truncating. So, if not specified, we assume * traditional behavior, e.g., just the normal data. */ if ((flags & (IO_EXT | IO_NORMAL)) == 0) flags |= IO_NORMAL; if (!DOINGSOFTDEP(vp) && !DOINGASYNC(vp)) flags |= IO_SYNC; waitforupdate = (flags & IO_SYNC) != 0 || !DOINGASYNC(vp); /* * If we are truncating the extended-attributes, and cannot * do it with soft updates, then do it slowly here. If we are * truncating both the extended attributes and the file contents * (e.g., the file is being unlinked), then pick it off with * soft updates below. */ allerror = 0; needextclean = 0; softdeptrunc = 0; journaltrunc = DOINGSUJ(vp); if (journaltrunc == 0 && DOINGSOFTDEP(vp) && length == 0) softdeptrunc = !softdep_slowdown(vp); extblocks = 0; datablocks = DIP(ip, i_blocks); if (fs->fs_magic == FS_UFS2_MAGIC && ip->i_din2->di_extsize > 0) { extblocks = btodb(fragroundup(fs, ip->i_din2->di_extsize)); datablocks -= extblocks; } if ((flags & IO_EXT) && extblocks > 0) { if (length != 0) panic("ffs_truncate: partial trunc of extdata"); if (softdeptrunc || journaltrunc) { if ((flags & IO_NORMAL) == 0) goto extclean; needextclean = 1; } else { if ((error = ffs_syncvnode(vp, MNT_WAIT, 0)) != 0) return (error); #ifdef QUOTA (void) chkdq(ip, -extblocks, NOCRED, 0); #endif vinvalbuf(vp, V_ALT, 0, 0); vn_pages_remove(vp, OFF_TO_IDX(lblktosize(fs, -extblocks)), 0); osize = ip->i_din2->di_extsize; ip->i_din2->di_blocks -= extblocks; ip->i_din2->di_extsize = 0; for (i = 0; i < UFS_NXADDR; i++) { oldblks[i] = ip->i_din2->di_extb[i]; ip->i_din2->di_extb[i] = 0; } ip->i_flag |= IN_CHANGE; if ((error = ffs_update(vp, waitforupdate))) return (error); for (i = 0; i < UFS_NXADDR; i++) { if (oldblks[i] == 0) continue; ffs_blkfree(ump, fs, ITODEVVP(ip), oldblks[i], sblksize(fs, osize, i), ip->i_number, vp->v_type, nil); } } } if ((flags & IO_NORMAL) == 0) return (0); if (vp->v_type == VLNK && (ip->i_size < vp->v_mount->mnt_maxsymlinklen || datablocks == 0)) { #ifdef INVARIANTS if (length != 0) panic("ffs_truncate: partial truncate of symlink"); #endif bzero(SHORTLINK(ip), (uint)ip->i_size); ip->i_size = 0; DIP_SET(ip, i_size, 0); ip->i_flag |= IN_CHANGE | IN_UPDATE; if (needextclean) goto extclean; return (ffs_update(vp, waitforupdate)); } if (ip->i_size == length) { ip->i_flag |= IN_CHANGE | IN_UPDATE; if (needextclean) goto extclean; return (ffs_update(vp, 0)); } if (fs->fs_ronly) panic("ffs_truncate: read-only filesystem"); if (IS_SNAPSHOT(ip)) ffs_snapremove(vp); vp->v_lasta = vp->v_clen = vp->v_cstart = vp->v_lastw = 0; osize = ip->i_size; /* * Lengthen the size of the file. We must ensure that the * last byte of the file is allocated. Since the smallest * value of osize is 0, length will be at least 1. */ if (osize < length) { vnode_pager_setsize(vp, length); flags |= BA_CLRBUF; error = UFS_BALLOC(vp, length - 1, 1, cred, flags, &bp); if (error) { vnode_pager_setsize(vp, osize); return (error); } ip->i_size = length; DIP_SET(ip, i_size, length); if (bp->b_bufsize == fs->fs_bsize) bp->b_flags |= B_CLUSTEROK; if (flags & IO_SYNC) bwrite(bp); else if (DOINGASYNC(vp)) bdwrite(bp); else bawrite(bp); ip->i_flag |= IN_CHANGE | IN_UPDATE; return (ffs_update(vp, waitforupdate)); } /* * Lookup block number for a given offset. Zero length files * have no blocks, so return a blkno of -1. */ lbn = lblkno(fs, length - 1); if (length == 0) { blkno = -1; } else if (lbn < UFS_NDADDR) { blkno = DIP(ip, i_db[lbn]); } else { error = UFS_BALLOC(vp, lblktosize(fs, (off_t)lbn), fs->fs_bsize, cred, BA_METAONLY, &bp); if (error) return (error); indiroff = (lbn - UFS_NDADDR) % NINDIR(fs); if (I_IS_UFS1(ip)) blkno = ((ufs1_daddr_t *)(bp->b_data))[indiroff]; else blkno = ((ufs2_daddr_t *)(bp->b_data))[indiroff]; /* * If the block number is non-zero, then the indirect block * must have been previously allocated and need not be written. * If the block number is zero, then we may have allocated * the indirect block and hence need to write it out. */ if (blkno != 0) brelse(bp); else if (flags & IO_SYNC) bwrite(bp); else bdwrite(bp); } /* * If the block number at the new end of the file is zero, * then we must allocate it to ensure that the last block of * the file is allocated. Soft updates does not handle this * case, so here we have to clean up the soft updates data * structures describing the allocation past the truncation * point. Finding and deallocating those structures is a lot of * work. Since partial truncation with a hole at the end occurs * rarely, we solve the problem by syncing the file so that it * will have no soft updates data structures left. */ if (blkno == 0 && (error = ffs_syncvnode(vp, MNT_WAIT, 0)) != 0) return (error); if (blkno != 0 && DOINGSOFTDEP(vp)) { if (softdeptrunc == 0 && journaltrunc == 0) { /* * If soft updates cannot handle this truncation, * clean up soft dependency data structures and * fall through to the synchronous truncation. */ if ((error = ffs_syncvnode(vp, MNT_WAIT, 0)) != 0) return (error); } else { flags = IO_NORMAL | (needextclean ? IO_EXT: 0); if (journaltrunc) softdep_journal_freeblocks(ip, cred, length, flags); else softdep_setup_freeblocks(ip, length, flags); ASSERT_VOP_LOCKED(vp, "ffs_truncate1"); if (journaltrunc == 0) { ip->i_flag |= IN_CHANGE | IN_UPDATE; error = ffs_update(vp, 0); } return (error); } } /* * Shorten the size of the file. If the last block of the * shortened file is unallocated, we must allocate it. * Additionally, if the file is not being truncated to a * block boundary, the contents of the partial block * following the end of the file must be zero'ed in * case it ever becomes accessible again because of * subsequent file growth. Directories however are not * zero'ed as they should grow back initialized to empty. */ offset = blkoff(fs, length); if (blkno != 0 && offset == 0) { ip->i_size = length; DIP_SET(ip, i_size, length); } else { lbn = lblkno(fs, length); flags |= BA_CLRBUF; error = UFS_BALLOC(vp, length - 1, 1, cred, flags, &bp); if (error) return (error); /* * When we are doing soft updates and the UFS_BALLOC * above fills in a direct block hole with a full sized * block that will be truncated down to a fragment below, * we must flush out the block dependency with an FSYNC * so that we do not get a soft updates inconsistency * when we create the fragment below. */ if (DOINGSOFTDEP(vp) && lbn < UFS_NDADDR && fragroundup(fs, blkoff(fs, length)) < fs->fs_bsize && (error = ffs_syncvnode(vp, MNT_WAIT, 0)) != 0) return (error); ip->i_size = length; DIP_SET(ip, i_size, length); size = blksize(fs, ip, lbn); if (vp->v_type != VDIR && offset != 0) bzero((char *)bp->b_data + offset, (uint)(size - offset)); /* Kirk's code has reallocbuf(bp, size, 1) here */ allocbuf(bp, size); if (bp->b_bufsize == fs->fs_bsize) bp->b_flags |= B_CLUSTEROK; if (flags & IO_SYNC) bwrite(bp); else if (DOINGASYNC(vp)) bdwrite(bp); else bawrite(bp); } /* * Calculate index into inode's block list of * last direct and indirect blocks (if any) * which we want to keep. Lastblock is -1 when * the file is truncated to 0. */ lastblock = lblkno(fs, length + fs->fs_bsize - 1) - 1; lastiblock[SINGLE] = lastblock - UFS_NDADDR; lastiblock[DOUBLE] = lastiblock[SINGLE] - NINDIR(fs); lastiblock[TRIPLE] = lastiblock[DOUBLE] - NINDIR(fs) * NINDIR(fs); nblocks = btodb(fs->fs_bsize); /* * Update file and block pointers on disk before we start freeing * blocks. If we crash before free'ing blocks below, the blocks * will be returned to the free list. lastiblock values are also * normalized to -1 for calls to ffs_indirtrunc below. */ for (level = TRIPLE; level >= SINGLE; level--) { oldblks[UFS_NDADDR + level] = DIP(ip, i_ib[level]); if (lastiblock[level] < 0) { DIP_SET(ip, i_ib[level], 0); lastiblock[level] = -1; } } for (i = 0; i < UFS_NDADDR; i++) { oldblks[i] = DIP(ip, i_db[i]); if (i > lastblock) DIP_SET(ip, i_db[i], 0); } ip->i_flag |= IN_CHANGE | IN_UPDATE; allerror = ffs_update(vp, waitforupdate); /* * Having written the new inode to disk, save its new configuration * and put back the old block pointers long enough to process them. * Note that we save the new block configuration so we can check it * when we are done. */ for (i = 0; i < UFS_NDADDR; i++) { newblks[i] = DIP(ip, i_db[i]); DIP_SET(ip, i_db[i], oldblks[i]); } for (i = 0; i < UFS_NIADDR; i++) { newblks[UFS_NDADDR + i] = DIP(ip, i_ib[i]); DIP_SET(ip, i_ib[i], oldblks[UFS_NDADDR + i]); } ip->i_size = osize; DIP_SET(ip, i_size, osize); error = vtruncbuf(vp, cred, length, fs->fs_bsize); if (error && (allerror == 0)) allerror = error; /* * Indirect blocks first. */ indir_lbn[SINGLE] = -UFS_NDADDR; indir_lbn[DOUBLE] = indir_lbn[SINGLE] - NINDIR(fs) - 1; indir_lbn[TRIPLE] = indir_lbn[DOUBLE] - NINDIR(fs) * NINDIR(fs) - 1; for (level = TRIPLE; level >= SINGLE; level--) { bn = DIP(ip, i_ib[level]); if (bn != 0) { error = ffs_indirtrunc(ip, indir_lbn[level], fsbtodb(fs, bn), lastiblock[level], level, &count); if (error) allerror = error; blocksreleased += count; if (lastiblock[level] < 0) { DIP_SET(ip, i_ib[level], 0); ffs_blkfree(ump, fs, ump->um_devvp, bn, fs->fs_bsize, ip->i_number, vp->v_type, nil); blocksreleased += nblocks; } } if (lastiblock[level] >= 0) goto done; } /* * All whole direct blocks or frags. */ for (i = UFS_NDADDR - 1; i > lastblock; i--) { long bsize; bn = DIP(ip, i_db[i]); if (bn == 0) continue; DIP_SET(ip, i_db[i], 0); bsize = blksize(fs, ip, i); ffs_blkfree(ump, fs, ump->um_devvp, bn, bsize, ip->i_number, vp->v_type, nil); blocksreleased += btodb(bsize); } if (lastblock < 0) goto done; /* * Finally, look for a change in size of the * last direct block; release any frags. */ bn = DIP(ip, i_db[lastblock]); if (bn != 0) { long oldspace, newspace; /* * Calculate amount of space we're giving * back as old block size minus new block size. */ oldspace = blksize(fs, ip, lastblock); ip->i_size = length; DIP_SET(ip, i_size, length); newspace = blksize(fs, ip, lastblock); if (newspace == 0) panic("ffs_truncate: newspace"); if (oldspace - newspace > 0) { /* * Block number of space to be free'd is * the old block # plus the number of frags * required for the storage we're keeping. */ bn += numfrags(fs, newspace); ffs_blkfree(ump, fs, ump->um_devvp, bn, oldspace - newspace, ip->i_number, vp->v_type, nil); blocksreleased += btodb(oldspace - newspace); } } done: #ifdef INVARIANTS for (level = SINGLE; level <= TRIPLE; level++) if (newblks[UFS_NDADDR + level] != DIP(ip, i_ib[level])) panic("ffs_truncate1"); for (i = 0; i < UFS_NDADDR; i++) if (newblks[i] != DIP(ip, i_db[i])) panic("ffs_truncate2"); BO_LOCK(bo); if (length == 0 && (fs->fs_magic != FS_UFS2_MAGIC || ip->i_din2->di_extsize == 0) && (bo->bo_dirty.bv_cnt > 0 || bo->bo_clean.bv_cnt > 0)) panic("ffs_truncate3"); BO_UNLOCK(bo); #endif /* INVARIANTS */ /* * Put back the real size. */ ip->i_size = length; DIP_SET(ip, i_size, length); if (DIP(ip, i_blocks) >= blocksreleased) DIP_SET(ip, i_blocks, DIP(ip, i_blocks) - blocksreleased); else /* sanity */ DIP_SET(ip, i_blocks, 0); ip->i_flag |= IN_CHANGE; #ifdef QUOTA (void) chkdq(ip, -blocksreleased, NOCRED, 0); #endif return (allerror); extclean: if (journaltrunc) softdep_journal_freeblocks(ip, cred, length, IO_EXT); else softdep_setup_freeblocks(ip, length, IO_EXT); return (ffs_update(vp, waitforupdate)); #endif // 0 return 0; }