/* $OpenBSD: ext2_alloc.c,v 1.3 1996/07/15 03:39:27 downsj Exp $ */ /* * modified for Lites 1.1 * * Aug 1995, Godmar Back (gback@cs.utah.edu) * University of Utah, Department of Computer Science */ /* * Copyright (c) 1982, 1986, 1989, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)ext2_alloc.c 8.8 (Berkeley) 2/21/94 */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include extern u_long nextgennumber; static void ext2_fserr __P((struct ext2_sb_info *, u_int, char *)); /* * Linux calls this functions at the following locations: * (1) the inode is freed * (2) a preallocation miss occurs * (3) truncate is called * (4) release_file is called and f_mode & 2 * * I call it in ext2_inactive, ext2_truncate, ext2_vfree and in (2) * the call in vfree might be redundant */ void ext2_discard_prealloc (struct inode * ip) { #ifdef EXT2_PREALLOCATE if (ip->i_prealloc_count) { int i = ip->i_prealloc_count; ip->i_prealloc_count = 0; ext2_free_blocks (ITOV(ip)->v_mount, ip->i_prealloc_block, i); } #endif } /* * Allocate a block in the file system. * * this takes the framework from ffs_alloc. To implement the * actual allocation, it calls ext2_new_block, the ported version * of the same Linux routine. * * we note that this is always called in connection with ext2_blkpref * * preallocation is done as Linux does it */ int ext2_alloc(ip, lbn, bpref, size, cred, bnp) register struct inode *ip; daddr_t lbn, bpref; int size; struct ucred *cred; daddr_t *bnp; { register struct ext2_sb_info *fs; daddr_t bno; #if QUOTA int error; #endif *bnp = 0; fs = ip->i_e2fs; #if DIAGNOSTIC if ((u_int)size > fs->s_blocksize || blkoff(fs, size) != 0) { printf("dev = 0x%x, bsize = %d, size = %d, fs = %s\n", ip->i_dev, fs->s_blocksize, size, fs->fs_fsmnt); panic("ext2_alloc: bad size"); } if (cred == NOCRED) panic("ext2_alloc: missing credential\n"); #endif /* DIAGNOSTIC */ if (size == fs->s_blocksize && fs->s_es->s_free_blocks_count == 0) goto nospace; if (cred->cr_uid != 0 && fs->s_es->s_free_blocks_count < fs->s_es->s_r_blocks_count) goto nospace; #if QUOTA if (error = chkdq(ip, (long)btodb(size), cred, 0)) return (error); #endif if (bpref >= fs->s_es->s_blocks_count) bpref = 0; /* call the Linux code */ #ifdef EXT2_PREALLOCATE /* To have a preallocation hit, we must * - have at least one block preallocated * - and our preferred block must have that block number or one below */ if (ip->i_prealloc_count && (bpref == ip->i_prealloc_block || bpref + 1 == ip->i_prealloc_block)) { bno = ip->i_prealloc_block++; ip->i_prealloc_count--; /* ext2_debug ("preallocation hit (%lu/%lu).\n", ++alloc_hits, ++alloc_attempts); */ /* Linux gets, clears, and releases the buffer at this point - we don't have to that; we leave it to the caller */ } else { ext2_discard_prealloc (ip); /* ext2_debug ("preallocation miss (%lu/%lu).\n", alloc_hits, ++alloc_attempts); */ if (S_ISREG(ip->i_mode)) bno = ext2_new_block (ITOV(ip)->v_mount, bpref, &ip->i_prealloc_count, &ip->i_prealloc_block); else bno = (daddr_t)ext2_new_block(ITOV(ip)->v_mount, bpref, 0, 0); } #else bno = (daddr_t)ext2_new_block(ITOV(ip)->v_mount, bpref, 0, 0); #endif if (bno > 0) { /* set next_alloc fields as done in block_getblk */ ip->i_next_alloc_block = lbn; ip->i_next_alloc_goal = bno; ip->i_blocks += btodb(size); ip->i_flag |= IN_CHANGE | IN_UPDATE; *bnp = bno; return (0); } #if QUOTA /* * Restore user's disk quota because allocation failed. */ (void) chkdq(ip, (long)-btodb(size), cred, FORCE); #endif nospace: ext2_fserr(fs, cred->cr_uid, "file system full"); uprintf("\n%s: write failed, file system is full\n", fs->fs_fsmnt); return (ENOSPC); } /* * Reallocate a sequence of blocks into a contiguous sequence of blocks. * * The vnode and an array of buffer pointers for a range of sequential * logical blocks to be made contiguous is given. The allocator attempts * to find a range of sequential blocks starting as close as possible to * an fs_rotdelay offset from the end of the allocation for the logical * block immediately preceeding the current range. If successful, the * physical block numbers in the buffer pointers and in the inode are * changed to reflect the new allocation. If unsuccessful, the allocation * is left unchanged. The success in doing the reallocation is returned. * Note that the error return is not reflected back to the user. Rather * the previous block allocation will be used. */ #ifdef FANCY_REALLOC #include static int doasyncfree = 1; #ifdef OPT_DEBUG SYSCTL_INT(_debug, 14, doasyncfree, CTLFLAG_RW, &doasyncfree, 0, ""); #endif /* OPT_DEBUG */ #endif int ext2_reallocblks(v) void *v; { struct vop_reallocblks_args /* { struct vnode *a_vp; struct cluster_save *a_buflist; } */ *ap = v; #ifndef FANCY_REALLOC /* printf("ext2_reallocblks not implemented\n"); */ return ENOSPC; #else struct ext2_sb_info *fs; struct inode *ip; struct vnode *vp; struct buf *sbp, *ebp; daddr_t *bap, *sbap, *ebap; struct cluster_save *buflist; daddr_t start_lbn, end_lbn, soff, eoff, newblk, blkno; struct indir start_ap[NIADDR + 1], end_ap[NIADDR + 1], *idp; int i, len, start_lvl, end_lvl, pref, ssize; struct timespec ts; vp = ap->a_vp; ip = VTOI(vp); fs = ip->i_e2fs; #ifdef UNKLAR if (fs->fs_contigsumsize <= 0) return (ENOSPC); #endif buflist = ap->a_buflist; len = buflist->bs_nchildren; start_lbn = buflist->bs_children[0]->b_lblkno; end_lbn = start_lbn + len - 1; #if DIAGNOSTIC for (i = 1; i < len; i++) if (buflist->bs_children[i]->b_lblkno != start_lbn + i) panic("ext2_reallocblks: non-cluster"); #endif /* * If the latest allocation is in a new cylinder group, assume that * the filesystem has decided to move and do not force it back to * the previous cylinder group. */ if (dtog(fs, dbtofsb(fs, buflist->bs_children[0]->b_blkno)) != dtog(fs, dbtofsb(fs, buflist->bs_children[len - 1]->b_blkno))) return (ENOSPC); if (ufs_getlbns(vp, start_lbn, start_ap, &start_lvl) || ufs_getlbns(vp, end_lbn, end_ap, &end_lvl)) return (ENOSPC); /* * Get the starting offset and block map for the first block. */ if (start_lvl == 0) { sbap = &ip->i_db[0]; soff = start_lbn; } else { idp = &start_ap[start_lvl - 1]; if (bread(vp, idp->in_lbn, (int)fs->s_blocksize, NOCRED, &sbp)) { brelse(sbp); return (ENOSPC); } sbap = (daddr_t *)sbp->b_data; soff = idp->in_off; } /* * Find the preferred location for the cluster. */ pref = ext2_blkpref(ip, start_lbn, soff, sbap); /* * If the block range spans two block maps, get the second map. */ if (end_lvl == 0 || (idp = &end_ap[end_lvl - 1])->in_off + 1 >= len) { ssize = len; } else { #if DIAGNOSTIC if (start_ap[start_lvl-1].in_lbn == idp->in_lbn) panic("ext2_reallocblk: start == end"); #endif ssize = len - (idp->in_off + 1); if (bread(vp, idp->in_lbn, (int)fs->s_blocksize, NOCRED, &ebp)) goto fail; ebap = (daddr_t *)ebp->b_data; } /* * Search the block map looking for an allocation of the desired size. */ if ((newblk = (daddr_t)ext2_hashalloc(ip, dtog(fs, pref), (long)pref, len, (u_long (*)())ext2_clusteralloc)) == 0) goto fail; /* * We have found a new contiguous block. * * First we have to replace the old block pointers with the new * block pointers in the inode and indirect blocks associated * with the file. */ blkno = newblk; for (bap = &sbap[soff], i = 0; i < len; i++, blkno += fs->s_frags_per_block) { if (i == ssize) bap = ebap; #if DIAGNOSTIC if (buflist->bs_children[i]->b_blkno != fsbtodb(fs, *bap)) panic("ext2_reallocblks: alloc mismatch"); #endif *bap++ = blkno; } /* * Next we must write out the modified inode and indirect blocks. * For strict correctness, the writes should be synchronous since * the old block values may have been written to disk. In practise * they are almost never written, but if we are concerned about * strict correctness, the `doasyncfree' flag should be set to zero. * * The test on `doasyncfree' should be changed to test a flag * that shows whether the associated buffers and inodes have * been written. The flag should be set when the cluster is * started and cleared whenever the buffer or inode is flushed. * We can then check below to see if it is set, and do the * synchronous write only when it has been cleared. */ TIMEVAL_TO_TIMESPEC(&time, &ts); if (sbap != &ip->i_db[0]) { if (doasyncfree) bdwrite(sbp); else bwrite(sbp); } else { ip->i_flag |= IN_CHANGE | IN_UPDATE; if (!doasyncfree) VOP_UPDATE(vp, &ts, &ts, MNT_WAIT); } if (ssize < len) if (doasyncfree) bdwrite(ebp); else bwrite(ebp); /* * Last, free the old blocks and assign the new blocks to the buffers. */ for (blkno = newblk, i = 0; i < len; i++, blkno += fs->s_frags_per_block) { ext2_blkfree(ip, dbtofsb(fs, buflist->bs_children[i]->b_blkno), fs->s_blocksize); buflist->bs_children[i]->b_blkno = fsbtodb(fs, blkno); } return (0); fail: if (ssize < len) brelse(ebp); if (sbap != &ip->i_db[0]) brelse(sbp); return (ENOSPC); #endif /* FANCY_REALLOC */ } /* * Allocate an inode in the file system. * * we leave the actual allocation strategy to the (modified) * ext2_new_inode(), to make sure we get the policies right */ int ext2_valloc(v) void *v; { struct vop_valloc_args /* { struct vnode *a_pvp; int a_mode; struct ucred *a_cred; struct vnode **a_vpp; } */ *ap = v; register struct vnode *pvp = ap->a_pvp; register struct inode *pip; register struct ext2_sb_info *fs; register struct inode *ip; mode_t mode = ap->a_mode; ino_t ino; int i, error; *ap->a_vpp = NULL; pip = VTOI(pvp); fs = pip->i_e2fs; if (fs->s_es->s_free_inodes_count == 0) goto noinodes; /* call the Linux routine - it returns the inode number only */ ino = ext2_new_inode(pip, mode); if (ino == 0) goto noinodes; error = VFS_VGET(pvp->v_mount, ino, ap->a_vpp); if (error) { VOP_VFREE(pvp, ino, mode); return (error); } ip = VTOI(*ap->a_vpp); /* the question is whether using VGET was such good idea at all - Linux doesn't read the old inode in when it's allocating a new one. I will set at least i_size & i_blocks the zero. */ ip->i_mode = 0; ip->i_size = 0; ip->i_blocks = 0; ip->i_flags = 0; /* now we want to make sure that the block pointers are zeroed out */ for(i = 0; i < EXT2_NDIR_BLOCKS; i++) ip->i_db[i] = 0; /* * Set up a new generation number for this inode. * XXX check if this makes sense in ext2 */ if (++nextgennumber < (u_long)time.tv_sec) nextgennumber = time.tv_sec; ip->i_gen = nextgennumber; /* printf("ext2_valloc: allocated inode %d\n", ino); */ return (0); noinodes: ext2_fserr(fs, ap->a_cred->cr_uid, "out of inodes"); uprintf("\n%s: create/symlink failed, no inodes free\n", fs->fs_fsmnt); return (ENOSPC); } /* * Select the desired position for the next block in a file. * * we try to mimic what Remy does in inode_getblk/block_getblk * * we note: blocknr == 0 means that we're about to allocate either * a direct block or a pointer block at the first level of indirection * (In other words, stuff that will go in i_db[] or i_ib[]) * * blocknr != 0 means that we're allocating a block that is none * of the above. Then, blocknr tells us the number of the block * that will hold the pointer */ daddr_t ext2_blkpref(ip, lbn, indx, bap, blocknr) struct inode *ip; daddr_t lbn; int indx; daddr_t *bap; daddr_t blocknr; { int tmp; /* if the next block is actually what we thought it is, then set the goal to what we thought it should be */ if(ip->i_next_alloc_block == lbn) return ip->i_next_alloc_goal; /* now check whether we were provided with an array that basically tells us previous blocks to which we want to stay closeby */ if(bap) for (tmp = indx - 1; tmp >= 0; tmp--) if (bap[tmp]) return bap[tmp]; /* else let's fall back to the blocknr, or, if there is none, follow the rule that a block should be allocated near it's inode */ return blocknr ? blocknr : (daddr_t)(ip->i_block_group * EXT2_BLOCKS_PER_GROUP(ip->i_e2fs)) + ip->i_e2fs->s_es->s_first_data_block; } /* * Free a block or fragment. * * pass on to the Linux code */ void ext2_blkfree(ip, bno, size) register struct inode *ip; daddr_t bno; long size; { register struct ext2_sb_info *fs; fs = ip->i_e2fs; /* * call Linux code with mount *, block number, count */ ext2_free_blocks(ITOV(ip)->v_mount, bno, size / fs->s_frag_size); } /* * Free an inode. * * the maintenance of the actual bitmaps is again up to the linux code */ int ext2_vfree(v) void *v; { struct vop_vfree_args /* { struct vnode *a_pvp; ino_t a_ino; int a_mode; } */ *ap = v; register struct ext2_sb_info *fs; register struct inode *pip; ino_t ino = ap->a_ino; int mode; pip = VTOI(ap->a_pvp); fs = pip->i_e2fs; if ((u_int)ino >= fs->s_inodes_per_group * fs->s_groups_count) panic("ifree: range: dev = 0x%x, ino = %d, fs = %s\n", pip->i_dev, ino, fs->fs_fsmnt); /* ext2_debug("ext2_vfree (%d, %d) called\n", pip->i_number, ap->a_mode); */ ext2_discard_prealloc(pip); /* we need to make sure that ext2_free_inode can adjust the used_dir_counts in the group summary information - I'd really like to know what the rationale behind this 'set i_mode to zero to denote an unused inode' is */ mode = pip->i_mode; pip->i_mode = ap->a_mode; ext2_free_inode(pip); pip->i_mode = mode; return (0); } /* * Fserr prints the name of a file system with an error diagnostic. * * The form of the error message is: * fs: error message */ static void ext2_fserr(fs, uid, cp) struct ext2_sb_info *fs; u_int uid; char *cp; { log(LOG_ERR, "uid %d on %s: %s\n", uid, fs->fs_fsmnt, cp); }