/* * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc. * All Rights Reserved. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation. * * This program is distributed in the hope that it would be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #include "xfs.h" #include "xfs_fs.h" #include "xfs_types.h" #include "xfs_bit.h" #include "xfs_log.h" #include "xfs_inum.h" #include "xfs_trans.h" #include "xfs_sb.h" #include "xfs_ag.h" #include "xfs_mount.h" #include "xfs_bmap_btree.h" #include "xfs_alloc_btree.h" #include "xfs_ialloc_btree.h" #include "xfs_dinode.h" #include "xfs_inode.h" #include "xfs_btree.h" #include "xfs_ialloc.h" #include "xfs_alloc.h" #include "xfs_rtalloc.h" #include "xfs_error.h" #include "xfs_bmap.h" /* * Allocation group level functions. */ static inline int xfs_ialloc_cluster_alignment( xfs_alloc_arg_t *args) { if (xfs_sb_version_hasalign(&args->mp->m_sb) && args->mp->m_sb.sb_inoalignmt >= XFS_B_TO_FSBT(args->mp, XFS_INODE_CLUSTER_SIZE(args->mp))) return args->mp->m_sb.sb_inoalignmt; return 1; } /* * Lookup a record by ino in the btree given by cur. */ int /* error */ xfs_inobt_lookup( struct xfs_btree_cur *cur, /* btree cursor */ xfs_agino_t ino, /* starting inode of chunk */ xfs_lookup_t dir, /* <=, >=, == */ int *stat) /* success/failure */ { cur->bc_rec.i.ir_startino = ino; cur->bc_rec.i.ir_freecount = 0; cur->bc_rec.i.ir_free = 0; return xfs_btree_lookup(cur, dir, stat); } /* * Update the record referred to by cur to the value given. * This either works (return 0) or gets an EFSCORRUPTED error. */ STATIC int /* error */ xfs_inobt_update( struct xfs_btree_cur *cur, /* btree cursor */ xfs_inobt_rec_incore_t *irec) /* btree record */ { union xfs_btree_rec rec; rec.inobt.ir_startino = cpu_to_be32(irec->ir_startino); rec.inobt.ir_freecount = cpu_to_be32(irec->ir_freecount); rec.inobt.ir_free = cpu_to_be64(irec->ir_free); return xfs_btree_update(cur, &rec); } /* * Get the data from the pointed-to record. */ int /* error */ xfs_inobt_get_rec( struct xfs_btree_cur *cur, /* btree cursor */ xfs_inobt_rec_incore_t *irec, /* btree record */ int *stat) /* output: success/failure */ { union xfs_btree_rec *rec; int error; error = xfs_btree_get_rec(cur, &rec, stat); if (!error && *stat == 1) { irec->ir_startino = be32_to_cpu(rec->inobt.ir_startino); irec->ir_freecount = be32_to_cpu(rec->inobt.ir_freecount); irec->ir_free = be64_to_cpu(rec->inobt.ir_free); } return error; } /* * Verify that the number of free inodes in the AGI is correct. */ #ifdef DEBUG STATIC int xfs_check_agi_freecount( struct xfs_btree_cur *cur, struct xfs_agi *agi) { if (cur->bc_nlevels == 1) { xfs_inobt_rec_incore_t rec; int freecount = 0; int error; int i; error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i); if (error) return error; do { error = xfs_inobt_get_rec(cur, &rec, &i); if (error) return error; if (i) { freecount += rec.ir_freecount; error = xfs_btree_increment(cur, 0, &i); if (error) return error; } } while (i == 1); if (!XFS_FORCED_SHUTDOWN(cur->bc_mp)) ASSERT(freecount == be32_to_cpu(agi->agi_freecount)); } return 0; } #else #define xfs_check_agi_freecount(cur, agi) 0 #endif /* * Initialise a new set of inodes. */ STATIC int xfs_ialloc_inode_init( struct xfs_mount *mp, struct xfs_trans *tp, xfs_agnumber_t agno, xfs_agblock_t agbno, xfs_agblock_t length, unsigned int gen) { struct xfs_buf *fbuf; struct xfs_dinode *free; int blks_per_cluster, nbufs, ninodes; int version; int i, j; xfs_daddr_t d; /* * Loop over the new block(s), filling in the inodes. * For small block sizes, manipulate the inodes in buffers * which are multiples of the blocks size. */ if (mp->m_sb.sb_blocksize >= XFS_INODE_CLUSTER_SIZE(mp)) { blks_per_cluster = 1; nbufs = length; ninodes = mp->m_sb.sb_inopblock; } else { blks_per_cluster = XFS_INODE_CLUSTER_SIZE(mp) / mp->m_sb.sb_blocksize; nbufs = length / blks_per_cluster; ninodes = blks_per_cluster * mp->m_sb.sb_inopblock; } /* * Figure out what version number to use in the inodes we create. * If the superblock version has caught up to the one that supports * the new inode format, then use the new inode version. Otherwise * use the old version so that old kernels will continue to be * able to use the file system. */ if (xfs_sb_version_hasnlink(&mp->m_sb)) version = 2; else version = 1; for (j = 0; j < nbufs; j++) { /* * Get the block. */ d = XFS_AGB_TO_DADDR(mp, agno, agbno + (j * blks_per_cluster)); fbuf = xfs_trans_get_buf(tp, mp->m_ddev_targp, d, mp->m_bsize * blks_per_cluster, 0); if (!fbuf) return ENOMEM; /* * Initialize all inodes in this buffer and then log them. * * XXX: It would be much better if we had just one transaction * to log a whole cluster of inodes instead of all the * individual transactions causing a lot of log traffic. */ xfs_buf_zero(fbuf, 0, ninodes << mp->m_sb.sb_inodelog); for (i = 0; i < ninodes; i++) { int ioffset = i << mp->m_sb.sb_inodelog; uint isize = sizeof(struct xfs_dinode); free = xfs_make_iptr(mp, fbuf, i); free->di_magic = cpu_to_be16(XFS_DINODE_MAGIC); free->di_version = version; free->di_gen = cpu_to_be32(gen); free->di_next_unlinked = cpu_to_be32(NULLAGINO); xfs_trans_log_buf(tp, fbuf, ioffset, ioffset + isize - 1); } xfs_trans_inode_alloc_buf(tp, fbuf); } return 0; } /* * Allocate new inodes in the allocation group specified by agbp. * Return 0 for success, else error code. */ STATIC int /* error code or 0 */ xfs_ialloc_ag_alloc( xfs_trans_t *tp, /* transaction pointer */ xfs_buf_t *agbp, /* alloc group buffer */ int *alloc) { xfs_agi_t *agi; /* allocation group header */ xfs_alloc_arg_t args; /* allocation argument structure */ xfs_btree_cur_t *cur; /* inode btree cursor */ xfs_agnumber_t agno; int error; int i; xfs_agino_t newino; /* new first inode's number */ xfs_agino_t newlen; /* new number of inodes */ xfs_agino_t thisino; /* current inode number, for loop */ int isaligned = 0; /* inode allocation at stripe unit */ /* boundary */ struct xfs_perag *pag; args.tp = tp; args.mp = tp->t_mountp; /* * Locking will ensure that we don't have two callers in here * at one time. */ newlen = XFS_IALLOC_INODES(args.mp); if (args.mp->m_maxicount && args.mp->m_sb.sb_icount + newlen > args.mp->m_maxicount) return XFS_ERROR(ENOSPC); args.minlen = args.maxlen = XFS_IALLOC_BLOCKS(args.mp); /* * First try to allocate inodes contiguous with the last-allocated * chunk of inodes. If the filesystem is striped, this will fill * an entire stripe unit with inodes. */ agi = XFS_BUF_TO_AGI(agbp); newino = be32_to_cpu(agi->agi_newino); agno = be32_to_cpu(agi->agi_seqno); args.agbno = XFS_AGINO_TO_AGBNO(args.mp, newino) + XFS_IALLOC_BLOCKS(args.mp); if (likely(newino != NULLAGINO && (args.agbno < be32_to_cpu(agi->agi_length)))) { args.fsbno = XFS_AGB_TO_FSB(args.mp, agno, args.agbno); args.type = XFS_ALLOCTYPE_THIS_BNO; args.mod = args.total = args.wasdel = args.isfl = args.userdata = args.minalignslop = 0; args.prod = 1; /* * We need to take into account alignment here to ensure that * we don't modify the free list if we fail to have an exact * block. If we don't have an exact match, and every oher * attempt allocation attempt fails, we'll end up cancelling * a dirty transaction and shutting down. * * For an exact allocation, alignment must be 1, * however we need to take cluster alignment into account when * fixing up the freelist. Use the minalignslop field to * indicate that extra blocks might be required for alignment, * but not to use them in the actual exact allocation. */ args.alignment = 1; args.minalignslop = xfs_ialloc_cluster_alignment(&args) - 1; /* Allow space for the inode btree to split. */ args.minleft = args.mp->m_in_maxlevels - 1; if ((error = xfs_alloc_vextent(&args))) return error; } else args.fsbno = NULLFSBLOCK; if (unlikely(args.fsbno == NULLFSBLOCK)) { /* * Set the alignment for the allocation. * If stripe alignment is turned on then align at stripe unit * boundary. * If the cluster size is smaller than a filesystem block * then we're doing I/O for inodes in filesystem block size * pieces, so don't need alignment anyway. */ isaligned = 0; if (args.mp->m_sinoalign) { ASSERT(!(args.mp->m_flags & XFS_MOUNT_NOALIGN)); args.alignment = args.mp->m_dalign; isaligned = 1; } else args.alignment = xfs_ialloc_cluster_alignment(&args); /* * Need to figure out where to allocate the inode blocks. * Ideally they should be spaced out through the a.g. * For now, just allocate blocks up front. */ args.agbno = be32_to_cpu(agi->agi_root); args.fsbno = XFS_AGB_TO_FSB(args.mp, agno, args.agbno); /* * Allocate a fixed-size extent of inodes. */ args.type = XFS_ALLOCTYPE_NEAR_BNO; args.mod = args.total = args.wasdel = args.isfl = args.userdata = args.minalignslop = 0; args.prod = 1; /* * Allow space for the inode btree to split. */ args.minleft = args.mp->m_in_maxlevels - 1; if ((error = xfs_alloc_vextent(&args))) return error; } /* * If stripe alignment is turned on, then try again with cluster * alignment. */ if (isaligned && args.fsbno == NULLFSBLOCK) { args.type = XFS_ALLOCTYPE_NEAR_BNO; args.agbno = be32_to_cpu(agi->agi_root); args.fsbno = XFS_AGB_TO_FSB(args.mp, agno, args.agbno); args.alignment = xfs_ialloc_cluster_alignment(&args); if ((error = xfs_alloc_vextent(&args))) return error; } if (args.fsbno == NULLFSBLOCK) { *alloc = 0; return 0; } ASSERT(args.len == args.minlen); /* * Stamp and write the inode buffers. * * Seed the new inode cluster with a random generation number. This * prevents short-term reuse of generation numbers if a chunk is * freed and then immediately reallocated. We use random numbers * rather than a linear progression to prevent the next generation * number from being easily guessable. */ error = xfs_ialloc_inode_init(args.mp, tp, agno, args.agbno, args.len, random32()); if (error) return error; /* * Convert the results. */ newino = XFS_OFFBNO_TO_AGINO(args.mp, args.agbno, 0); be32_add_cpu(&agi->agi_count, newlen); be32_add_cpu(&agi->agi_freecount, newlen); pag = xfs_perag_get(args.mp, agno); pag->pagi_freecount += newlen; xfs_perag_put(pag); agi->agi_newino = cpu_to_be32(newino); /* * Insert records describing the new inode chunk into the btree. */ cur = xfs_inobt_init_cursor(args.mp, tp, agbp, agno); for (thisino = newino; thisino < newino + newlen; thisino += XFS_INODES_PER_CHUNK) { cur->bc_rec.i.ir_startino = thisino; cur->bc_rec.i.ir_freecount = XFS_INODES_PER_CHUNK; cur->bc_rec.i.ir_free = XFS_INOBT_ALL_FREE; error = xfs_btree_lookup(cur, XFS_LOOKUP_EQ, &i); if (error) { xfs_btree_del_cursor(cur, XFS_BTREE_ERROR); return error; } ASSERT(i == 0); error = xfs_btree_insert(cur, &i); if (error) { xfs_btree_del_cursor(cur, XFS_BTREE_ERROR); return error; } ASSERT(i == 1); } xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR); /* * Log allocation group header fields */ xfs_ialloc_log_agi(tp, agbp, XFS_AGI_COUNT | XFS_AGI_FREECOUNT | XFS_AGI_NEWINO); /* * Modify/log superblock values for inode count and inode free count. */ xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, (long)newlen); xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, (long)newlen); *alloc = 1; return 0; } STATIC xfs_agnumber_t xfs_ialloc_next_ag( xfs_mount_t *mp) { xfs_agnumber_t agno; spin_lock(&mp->m_agirotor_lock); agno = mp->m_agirotor; if (++mp->m_agirotor == mp->m_maxagi) mp->m_agirotor = 0; spin_unlock(&mp->m_agirotor_lock); return agno; } /* * Select an allocation group to look for a free inode in, based on the parent * inode and then mode. Return the allocation group buffer. */ STATIC xfs_buf_t * /* allocation group buffer */ xfs_ialloc_ag_select( xfs_trans_t *tp, /* transaction pointer */ xfs_ino_t parent, /* parent directory inode number */ umode_t mode, /* bits set to indicate file type */ int okalloc) /* ok to allocate more space */ { xfs_buf_t *agbp; /* allocation group header buffer */ xfs_agnumber_t agcount; /* number of ag's in the filesystem */ xfs_agnumber_t agno; /* current ag number */ int flags; /* alloc buffer locking flags */ xfs_extlen_t ineed; /* blocks needed for inode allocation */ xfs_extlen_t longest = 0; /* longest extent available */ xfs_mount_t *mp; /* mount point structure */ int needspace; /* file mode implies space allocated */ xfs_perag_t *pag; /* per allocation group data */ xfs_agnumber_t pagno; /* parent (starting) ag number */ /* * Files of these types need at least one block if length > 0 * (and they won't fit in the inode, but that's hard to figure out). */ needspace = S_ISDIR(mode) || S_ISREG(mode) || S_ISLNK(mode); mp = tp->t_mountp; agcount = mp->m_maxagi; if (S_ISDIR(mode)) pagno = xfs_ialloc_next_ag(mp); else { pagno = XFS_INO_TO_AGNO(mp, parent); if (pagno >= agcount) pagno = 0; } ASSERT(pagno < agcount); /* * Loop through allocation groups, looking for one with a little * free space in it. Note we don't look for free inodes, exactly. * Instead, we include whether there is a need to allocate inodes * to mean that blocks must be allocated for them, * if none are currently free. */ agno = pagno; flags = XFS_ALLOC_FLAG_TRYLOCK; for (;;) { pag = xfs_perag_get(mp, agno); if (!pag->pagi_init) { if (xfs_ialloc_read_agi(mp, tp, agno, &agbp)) { agbp = NULL; goto nextag; } } else agbp = NULL; if (!pag->pagi_inodeok) { xfs_ialloc_next_ag(mp); goto unlock_nextag; } /* * Is there enough free space for the file plus a block * of inodes (if we need to allocate some)? */ ineed = pag->pagi_freecount ? 0 : XFS_IALLOC_BLOCKS(mp); if (ineed && !pag->pagf_init) { if (agbp == NULL && xfs_ialloc_read_agi(mp, tp, agno, &agbp)) { agbp = NULL; goto nextag; } (void)xfs_alloc_pagf_init(mp, tp, agno, flags); } if (!ineed || pag->pagf_init) { if (ineed && !(longest = pag->pagf_longest)) longest = pag->pagf_flcount > 0; if (!ineed || (pag->pagf_freeblks >= needspace + ineed && longest >= ineed && okalloc)) { if (agbp == NULL && xfs_ialloc_read_agi(mp, tp, agno, &agbp)) { agbp = NULL; goto nextag; } xfs_perag_put(pag); return agbp; } } unlock_nextag: if (agbp) xfs_trans_brelse(tp, agbp); nextag: xfs_perag_put(pag); /* * No point in iterating over the rest, if we're shutting * down. */ if (XFS_FORCED_SHUTDOWN(mp)) return NULL; agno++; if (agno >= agcount) agno = 0; if (agno == pagno) { if (flags == 0) return NULL; flags = 0; } } } /* * Try to retrieve the next record to the left/right from the current one. */ STATIC int xfs_ialloc_next_rec( struct xfs_btree_cur *cur, xfs_inobt_rec_incore_t *rec, int *done, int left) { int error; int i; if (left) error = xfs_btree_decrement(cur, 0, &i); else error = xfs_btree_increment(cur, 0, &i); if (error) return error; *done = !i; if (i) { error = xfs_inobt_get_rec(cur, rec, &i); if (error) return error; XFS_WANT_CORRUPTED_RETURN(i == 1); } return 0; } STATIC int xfs_ialloc_get_rec( struct xfs_btree_cur *cur, xfs_agino_t agino, xfs_inobt_rec_incore_t *rec, int *done, int left) { int error; int i; error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_EQ, &i); if (error) return error; *done = !i; if (i) { error = xfs_inobt_get_rec(cur, rec, &i); if (error) return error; XFS_WANT_CORRUPTED_RETURN(i == 1); } return 0; } /* * Allocate an inode. * * The caller selected an AG for us, and made sure that free inodes are * available. */ STATIC int xfs_dialloc_ag( struct xfs_trans *tp, struct xfs_buf *agbp, xfs_ino_t parent, xfs_ino_t *inop) { struct xfs_mount *mp = tp->t_mountp; struct xfs_agi *agi = XFS_BUF_TO_AGI(agbp); xfs_agnumber_t agno = be32_to_cpu(agi->agi_seqno); xfs_agnumber_t pagno = XFS_INO_TO_AGNO(mp, parent); xfs_agino_t pagino = XFS_INO_TO_AGINO(mp, parent); struct xfs_perag *pag; struct xfs_btree_cur *cur, *tcur; struct xfs_inobt_rec_incore rec, trec; xfs_ino_t ino; int error; int offset; int i, j; pag = xfs_perag_get(mp, agno); ASSERT(pag->pagi_init); ASSERT(pag->pagi_inodeok); ASSERT(pag->pagi_freecount > 0); restart_pagno: cur = xfs_inobt_init_cursor(mp, tp, agbp, agno); /* * If pagino is 0 (this is the root inode allocation) use newino. * This must work because we've just allocated some. */ if (!pagino) pagino = be32_to_cpu(agi->agi_newino); error = xfs_check_agi_freecount(cur, agi); if (error) goto error0; /* * If in the same AG as the parent, try to get near the parent. */ if (pagno == agno) { int doneleft; /* done, to the left */ int doneright; /* done, to the right */ int searchdistance = 10; error = xfs_inobt_lookup(cur, pagino, XFS_LOOKUP_LE, &i); if (error) goto error0; XFS_WANT_CORRUPTED_GOTO(i == 1, error0); error = xfs_inobt_get_rec(cur, &rec, &j); if (error) goto error0; XFS_WANT_CORRUPTED_GOTO(i == 1, error0); if (rec.ir_freecount > 0) { /* * Found a free inode in the same chunk * as the parent, done. */ goto alloc_inode; } /* * In the same AG as parent, but parent's chunk is full. */ /* duplicate the cursor, search left & right simultaneously */ error = xfs_btree_dup_cursor(cur, &tcur); if (error) goto error0; /* * Skip to last blocks looked up if same parent inode. */ if (pagino != NULLAGINO && pag->pagl_pagino == pagino && pag->pagl_leftrec != NULLAGINO && pag->pagl_rightrec != NULLAGINO) { error = xfs_ialloc_get_rec(tcur, pag->pagl_leftrec, &trec, &doneleft, 1); if (error) goto error1; error = xfs_ialloc_get_rec(cur, pag->pagl_rightrec, &rec, &doneright, 0); if (error) goto error1; } else { /* search left with tcur, back up 1 record */ error = xfs_ialloc_next_rec(tcur, &trec, &doneleft, 1); if (error) goto error1; /* search right with cur, go forward 1 record. */ error = xfs_ialloc_next_rec(cur, &rec, &doneright, 0); if (error) goto error1; } /* * Loop until we find an inode chunk with a free inode. */ while (!doneleft || !doneright) { int useleft; /* using left inode chunk this time */ if (!--searchdistance) { /* * Not in range - save last search * location and allocate a new inode */ xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR); pag->pagl_leftrec = trec.ir_startino; pag->pagl_rightrec = rec.ir_startino; pag->pagl_pagino = pagino; goto newino; } /* figure out the closer block if both are valid. */ if (!doneleft && !doneright) { useleft = pagino - (trec.ir_startino + XFS_INODES_PER_CHUNK - 1) < rec.ir_startino - pagino; } else { useleft = !doneleft; } /* free inodes to the left? */ if (useleft && trec.ir_freecount) { rec = trec; xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR); cur = tcur; pag->pagl_leftrec = trec.ir_startino; pag->pagl_rightrec = rec.ir_startino; pag->pagl_pagino = pagino; goto alloc_inode; } /* free inodes to the right? */ if (!useleft && rec.ir_freecount) { xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR); pag->pagl_leftrec = trec.ir_startino; pag->pagl_rightrec = rec.ir_startino; pag->pagl_pagino = pagino; goto alloc_inode; } /* get next record to check */ if (useleft) { error = xfs_ialloc_next_rec(tcur, &trec, &doneleft, 1); } else { error = xfs_ialloc_next_rec(cur, &rec, &doneright, 0); } if (error) goto error1; } /* * We've reached the end of the btree. because * we are only searching a small chunk of the * btree each search, there is obviously free * inodes closer to the parent inode than we * are now. restart the search again. */ pag->pagl_pagino = NULLAGINO; pag->pagl_leftrec = NULLAGINO; pag->pagl_rightrec = NULLAGINO; xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR); xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR); goto restart_pagno; } /* * In a different AG from the parent. * See if the most recently allocated block has any free. */ newino: if (agi->agi_newino != cpu_to_be32(NULLAGINO)) { error = xfs_inobt_lookup(cur, be32_to_cpu(agi->agi_newino), XFS_LOOKUP_EQ, &i); if (error) goto error0; if (i == 1) { error = xfs_inobt_get_rec(cur, &rec, &j); if (error) goto error0; if (j == 1 && rec.ir_freecount > 0) { /* * The last chunk allocated in the group * still has a free inode. */ goto alloc_inode; } } } /* * None left in the last group, search the whole AG */ error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i); if (error) goto error0; XFS_WANT_CORRUPTED_GOTO(i == 1, error0); for (;;) { error = xfs_inobt_get_rec(cur, &rec, &i); if (error) goto error0; XFS_WANT_CORRUPTED_GOTO(i == 1, error0); if (rec.ir_freecount > 0) break; error = xfs_btree_increment(cur, 0, &i); if (error) goto error0; XFS_WANT_CORRUPTED_GOTO(i == 1, error0); } alloc_inode: offset = xfs_lowbit64(rec.ir_free); ASSERT(offset >= 0); ASSERT(offset < XFS_INODES_PER_CHUNK); ASSERT((XFS_AGINO_TO_OFFSET(mp, rec.ir_startino) % XFS_INODES_PER_CHUNK) == 0); ino = XFS_AGINO_TO_INO(mp, agno, rec.ir_startino + offset); rec.ir_free &= ~XFS_INOBT_MASK(offset); rec.ir_freecount--; error = xfs_inobt_update(cur, &rec); if (error) goto error0; be32_add_cpu(&agi->agi_freecount, -1); xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT); pag->pagi_freecount--; error = xfs_check_agi_freecount(cur, agi); if (error) goto error0; xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR); xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -1); xfs_perag_put(pag); *inop = ino; return 0; error1: xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR); error0: xfs_btree_del_cursor(cur, XFS_BTREE_ERROR); xfs_perag_put(pag); return error; } /* * Allocate an inode on disk. * * Mode is used to tell whether the new inode will need space, and whether it * is a directory. * * This function is designed to be called twice if it has to do an allocation * to make more free inodes. On the first call, *IO_agbp should be set to NULL. * If an inode is available without having to performn an allocation, an inode * number is returned. In this case, *IO_agbp would be NULL. If an allocation * needes to be done, xfs_dialloc would return the current AGI buffer in * *IO_agbp. The caller should then commit the current transaction, allocate a * new transaction, and call xfs_dialloc() again, passing in the previous value * of *IO_agbp. IO_agbp should be held across the transactions. Since the AGI * buffer is locked across the two calls, the second call is guaranteed to have * a free inode available. * * Once we successfully pick an inode its number is returned and the on-disk * data structures are updated. The inode itself is not read in, since doing so * would break ordering constraints with xfs_reclaim. */ int xfs_dialloc( struct xfs_trans *tp, xfs_ino_t parent, umode_t mode, int okalloc, struct xfs_buf **IO_agbp, xfs_ino_t *inop) { struct xfs_buf *agbp; xfs_agnumber_t agno; struct xfs_agi *agi; int error; int ialloced; int noroom = 0; struct xfs_mount *mp; xfs_agnumber_t tagno; struct xfs_perag *pag; if (*IO_agbp) { /* * If the caller passes in a pointer to the AGI buffer, * continue where we left off before. In this case, we * know that the allocation group has free inodes. */ agbp = *IO_agbp; goto out_alloc; } /* * We do not have an agbp, so select an initial allocation * group for inode allocation. */ agbp = xfs_ialloc_ag_select(tp, parent, mode, okalloc); /* * Couldn't find an allocation group satisfying the * criteria, give up. */ if (!agbp) { *inop = NULLFSINO; return 0; } agi = XFS_BUF_TO_AGI(agbp); mp = tp->t_mountp; agno = be32_to_cpu(agi->agi_seqno); tagno = agno; /* * If we have already hit the ceiling of inode blocks then clear * okalloc so we scan all available agi structures for a free * inode. */ if (mp->m_maxicount && mp->m_sb.sb_icount + XFS_IALLOC_INODES(mp) > mp->m_maxicount) { noroom = 1; okalloc = 0; } /* * Loop until we find an allocation group that either has free inodes * or in which we can allocate some inodes. Iterate through the * allocation groups upward, wrapping at the end. */ while (!agi->agi_freecount) { /* * Don't do anything if we're not supposed to allocate * any blocks, just go on to the next ag. */ if (okalloc) { /* * Try to allocate some new inodes in the allocation * group. */ if ((error = xfs_ialloc_ag_alloc(tp, agbp, &ialloced))) { xfs_trans_brelse(tp, agbp); if (error == ENOSPC) { *inop = NULLFSINO; return 0; } else return error; } if (ialloced) { /* * We successfully allocated some inodes, return * the current context to the caller so that it * can commit the current transaction and call * us again where we left off. */ ASSERT(be32_to_cpu(agi->agi_freecount) > 0); *IO_agbp = agbp; *inop = NULLFSINO; return 0; } } /* * If it failed, give up on this ag. */ xfs_trans_brelse(tp, agbp); /* * Go on to the next ag: get its ag header. */ nextag: if (++tagno == mp->m_sb.sb_agcount) tagno = 0; if (tagno == agno) { *inop = NULLFSINO; return noroom ? ENOSPC : 0; } pag = xfs_perag_get(mp, tagno); if (pag->pagi_inodeok == 0) { xfs_perag_put(pag); goto nextag; } error = xfs_ialloc_read_agi(mp, tp, tagno, &agbp); xfs_perag_put(pag); if (error) goto nextag; agi = XFS_BUF_TO_AGI(agbp); ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC)); } out_alloc: *IO_agbp = NULL; return xfs_dialloc_ag(tp, agbp, parent, inop); } /* * Free disk inode. Carefully avoids touching the incore inode, all * manipulations incore are the caller's responsibility. * The on-disk inode is not changed by this operation, only the * btree (free inode mask) is changed. */ int xfs_difree( xfs_trans_t *tp, /* transaction pointer */ xfs_ino_t inode, /* inode to be freed */ xfs_bmap_free_t *flist, /* extents to free */ int *delete, /* set if inode cluster was deleted */ xfs_ino_t *first_ino) /* first inode in deleted cluster */ { /* REFERENCED */ xfs_agblock_t agbno; /* block number containing inode */ xfs_buf_t *agbp; /* buffer containing allocation group header */ xfs_agino_t agino; /* inode number relative to allocation group */ xfs_agnumber_t agno; /* allocation group number */ xfs_agi_t *agi; /* allocation group header */ xfs_btree_cur_t *cur; /* inode btree cursor */ int error; /* error return value */ int i; /* result code */ int ilen; /* inodes in an inode cluster */ xfs_mount_t *mp; /* mount structure for filesystem */ int off; /* offset of inode in inode chunk */ xfs_inobt_rec_incore_t rec; /* btree record */ struct xfs_perag *pag; mp = tp->t_mountp; /* * Break up inode number into its components. */ agno = XFS_INO_TO_AGNO(mp, inode); if (agno >= mp->m_sb.sb_agcount) { xfs_warn(mp, "%s: agno >= mp->m_sb.sb_agcount (%d >= %d).", __func__, agno, mp->m_sb.sb_agcount); ASSERT(0); return XFS_ERROR(EINVAL); } agino = XFS_INO_TO_AGINO(mp, inode); if (inode != XFS_AGINO_TO_INO(mp, agno, agino)) { xfs_warn(mp, "%s: inode != XFS_AGINO_TO_INO() (%llu != %llu).", __func__, (unsigned long long)inode, (unsigned long long)XFS_AGINO_TO_INO(mp, agno, agino)); ASSERT(0); return XFS_ERROR(EINVAL); } agbno = XFS_AGINO_TO_AGBNO(mp, agino); if (agbno >= mp->m_sb.sb_agblocks) { xfs_warn(mp, "%s: agbno >= mp->m_sb.sb_agblocks (%d >= %d).", __func__, agbno, mp->m_sb.sb_agblocks); ASSERT(0); return XFS_ERROR(EINVAL); } /* * Get the allocation group header. */ error = xfs_ialloc_read_agi(mp, tp, agno, &agbp); if (error) { xfs_warn(mp, "%s: xfs_ialloc_read_agi() returned error %d.", __func__, error); return error; } agi = XFS_BUF_TO_AGI(agbp); ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC)); ASSERT(agbno < be32_to_cpu(agi->agi_length)); /* * Initialize the cursor. */ cur = xfs_inobt_init_cursor(mp, tp, agbp, agno); error = xfs_check_agi_freecount(cur, agi); if (error) goto error0; /* * Look for the entry describing this inode. */ if ((error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i))) { xfs_warn(mp, "%s: xfs_inobt_lookup() returned error %d.", __func__, error); goto error0; } XFS_WANT_CORRUPTED_GOTO(i == 1, error0); error = xfs_inobt_get_rec(cur, &rec, &i); if (error) { xfs_warn(mp, "%s: xfs_inobt_get_rec() returned error %d.", __func__, error); goto error0; } XFS_WANT_CORRUPTED_GOTO(i == 1, error0); /* * Get the offset in the inode chunk. */ off = agino - rec.ir_startino; ASSERT(off >= 0 && off < XFS_INODES_PER_CHUNK); ASSERT(!(rec.ir_free & XFS_INOBT_MASK(off))); /* * Mark the inode free & increment the count. */ rec.ir_free |= XFS_INOBT_MASK(off); rec.ir_freecount++; /* * When an inode cluster is free, it becomes eligible for removal */ if (!(mp->m_flags & XFS_MOUNT_IKEEP) && (rec.ir_freecount == XFS_IALLOC_INODES(mp))) { *delete = 1; *first_ino = XFS_AGINO_TO_INO(mp, agno, rec.ir_startino); /* * Remove the inode cluster from the AGI B+Tree, adjust the * AGI and Superblock inode counts, and mark the disk space * to be freed when the transaction is committed. */ ilen = XFS_IALLOC_INODES(mp); be32_add_cpu(&agi->agi_count, -ilen); be32_add_cpu(&agi->agi_freecount, -(ilen - 1)); xfs_ialloc_log_agi(tp, agbp, XFS_AGI_COUNT | XFS_AGI_FREECOUNT); pag = xfs_perag_get(mp, agno); pag->pagi_freecount -= ilen - 1; xfs_perag_put(pag); xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, -ilen); xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -(ilen - 1)); if ((error = xfs_btree_delete(cur, &i))) { xfs_warn(mp, "%s: xfs_btree_delete returned error %d.", __func__, error); goto error0; } xfs_bmap_add_free(XFS_AGB_TO_FSB(mp, agno, XFS_INO_TO_AGBNO(mp,rec.ir_startino)), XFS_IALLOC_BLOCKS(mp), flist, mp); } else { *delete = 0; error = xfs_inobt_update(cur, &rec); if (error) { xfs_warn(mp, "%s: xfs_inobt_update returned error %d.", __func__, error); goto error0; } /* * Change the inode free counts and log the ag/sb changes. */ be32_add_cpu(&agi->agi_freecount, 1); xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT); pag = xfs_perag_get(mp, agno); pag->pagi_freecount++; xfs_perag_put(pag); xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, 1); } error = xfs_check_agi_freecount(cur, agi); if (error) goto error0; xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR); return 0; error0: xfs_btree_del_cursor(cur, XFS_BTREE_ERROR); return error; } STATIC int xfs_imap_lookup( struct xfs_mount *mp, struct xfs_trans *tp, xfs_agnumber_t agno, xfs_agino_t agino, xfs_agblock_t agbno, xfs_agblock_t *chunk_agbno, xfs_agblock_t *offset_agbno, int flags) { struct xfs_inobt_rec_incore rec; struct xfs_btree_cur *cur; struct xfs_buf *agbp; int error; int i; error = xfs_ialloc_read_agi(mp, tp, agno, &agbp); if (error) { xfs_alert(mp, "%s: xfs_ialloc_read_agi() returned error %d, agno %d", __func__, error, agno); return error; } /* * Lookup the inode record for the given agino. If the record cannot be * found, then it's an invalid inode number and we should abort. Once * we have a record, we need to ensure it contains the inode number * we are looking up. */ cur = xfs_inobt_init_cursor(mp, tp, agbp, agno); error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i); if (!error) { if (i) error = xfs_inobt_get_rec(cur, &rec, &i); if (!error && i == 0) error = EINVAL; } xfs_trans_brelse(tp, agbp); xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR); if (error) return error; /* check that the returned record contains the required inode */ if (rec.ir_startino > agino || rec.ir_startino + XFS_IALLOC_INODES(mp) <= agino) return EINVAL; /* for untrusted inodes check it is allocated first */ if ((flags & XFS_IGET_UNTRUSTED) && (rec.ir_free & XFS_INOBT_MASK(agino - rec.ir_startino))) return EINVAL; *chunk_agbno = XFS_AGINO_TO_AGBNO(mp, rec.ir_startino); *offset_agbno = agbno - *chunk_agbno; return 0; } /* * Return the location of the inode in imap, for mapping it into a buffer. */ int xfs_imap( xfs_mount_t *mp, /* file system mount structure */ xfs_trans_t *tp, /* transaction pointer */ xfs_ino_t ino, /* inode to locate */ struct xfs_imap *imap, /* location map structure */ uint flags) /* flags for inode btree lookup */ { xfs_agblock_t agbno; /* block number of inode in the alloc group */ xfs_agino_t agino; /* inode number within alloc group */ xfs_agnumber_t agno; /* allocation group number */ int blks_per_cluster; /* num blocks per inode cluster */ xfs_agblock_t chunk_agbno; /* first block in inode chunk */ xfs_agblock_t cluster_agbno; /* first block in inode cluster */ int error; /* error code */ int offset; /* index of inode in its buffer */ int offset_agbno; /* blks from chunk start to inode */ ASSERT(ino != NULLFSINO); /* * Split up the inode number into its parts. */ agno = XFS_INO_TO_AGNO(mp, ino); agino = XFS_INO_TO_AGINO(mp, ino); agbno = XFS_AGINO_TO_AGBNO(mp, agino); if (agno >= mp->m_sb.sb_agcount || agbno >= mp->m_sb.sb_agblocks || ino != XFS_AGINO_TO_INO(mp, agno, agino)) { #ifdef DEBUG /* * Don't output diagnostic information for untrusted inodes * as they can be invalid without implying corruption. */ if (flags & XFS_IGET_UNTRUSTED) return XFS_ERROR(EINVAL); if (agno >= mp->m_sb.sb_agcount) { xfs_alert(mp, "%s: agno (%d) >= mp->m_sb.sb_agcount (%d)", __func__, agno, mp->m_sb.sb_agcount); } if (agbno >= mp->m_sb.sb_agblocks) { xfs_alert(mp, "%s: agbno (0x%llx) >= mp->m_sb.sb_agblocks (0x%lx)", __func__, (unsigned long long)agbno, (unsigned long)mp->m_sb.sb_agblocks); } if (ino != XFS_AGINO_TO_INO(mp, agno, agino)) { xfs_alert(mp, "%s: ino (0x%llx) != XFS_AGINO_TO_INO() (0x%llx)", __func__, ino, XFS_AGINO_TO_INO(mp, agno, agino)); } xfs_stack_trace(); #endif /* DEBUG */ return XFS_ERROR(EINVAL); } blks_per_cluster = XFS_INODE_CLUSTER_SIZE(mp) >> mp->m_sb.sb_blocklog; /* * For bulkstat and handle lookups, we have an untrusted inode number * that we have to verify is valid. We cannot do this just by reading * the inode buffer as it may have been unlinked and removed leaving * inodes in stale state on disk. Hence we have to do a btree lookup * in all cases where an untrusted inode number is passed. */ if (flags & XFS_IGET_UNTRUSTED) { error = xfs_imap_lookup(mp, tp, agno, agino, agbno, &chunk_agbno, &offset_agbno, flags); if (error) return error; goto out_map; } /* * If the inode cluster size is the same as the blocksize or * smaller we get to the buffer by simple arithmetics. */ if (XFS_INODE_CLUSTER_SIZE(mp) <= mp->m_sb.sb_blocksize) { offset = XFS_INO_TO_OFFSET(mp, ino); ASSERT(offset < mp->m_sb.sb_inopblock); imap->im_blkno = XFS_AGB_TO_DADDR(mp, agno, agbno); imap->im_len = XFS_FSB_TO_BB(mp, 1); imap->im_boffset = (ushort)(offset << mp->m_sb.sb_inodelog); return 0; } /* * If the inode chunks are aligned then use simple maths to * find the location. Otherwise we have to do a btree * lookup to find the location. */ if (mp->m_inoalign_mask) { offset_agbno = agbno & mp->m_inoalign_mask; chunk_agbno = agbno - offset_agbno; } else { error = xfs_imap_lookup(mp, tp, agno, agino, agbno, &chunk_agbno, &offset_agbno, flags); if (error) return error; } out_map: ASSERT(agbno >= chunk_agbno); cluster_agbno = chunk_agbno + ((offset_agbno / blks_per_cluster) * blks_per_cluster); offset = ((agbno - cluster_agbno) * mp->m_sb.sb_inopblock) + XFS_INO_TO_OFFSET(mp, ino); imap->im_blkno = XFS_AGB_TO_DADDR(mp, agno, cluster_agbno); imap->im_len = XFS_FSB_TO_BB(mp, blks_per_cluster); imap->im_boffset = (ushort)(offset << mp->m_sb.sb_inodelog); /* * If the inode number maps to a block outside the bounds * of the file system then return NULL rather than calling * read_buf and panicing when we get an error from the * driver. */ if ((imap->im_blkno + imap->im_len) > XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks)) { xfs_alert(mp, "%s: (im_blkno (0x%llx) + im_len (0x%llx)) > sb_dblocks (0x%llx)", __func__, (unsigned long long) imap->im_blkno, (unsigned long long) imap->im_len, XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks)); return XFS_ERROR(EINVAL); } return 0; } /* * Compute and fill in value of m_in_maxlevels. */ void xfs_ialloc_compute_maxlevels( xfs_mount_t *mp) /* file system mount structure */ { int level; uint maxblocks; uint maxleafents; int minleafrecs; int minnoderecs; maxleafents = (1LL << XFS_INO_AGINO_BITS(mp)) >> XFS_INODES_PER_CHUNK_LOG; minleafrecs = mp->m_alloc_mnr[0]; minnoderecs = mp->m_alloc_mnr[1]; maxblocks = (maxleafents + minleafrecs - 1) / minleafrecs; for (level = 1; maxblocks > 1; level++) maxblocks = (maxblocks + minnoderecs - 1) / minnoderecs; mp->m_in_maxlevels = level; } /* * Log specified fields for the ag hdr (inode section) */ void xfs_ialloc_log_agi( xfs_trans_t *tp, /* transaction pointer */ xfs_buf_t *bp, /* allocation group header buffer */ int fields) /* bitmask of fields to log */ { int first; /* first byte number */ int last; /* last byte number */ static const short offsets[] = { /* field starting offsets */ /* keep in sync with bit definitions */ offsetof(xfs_agi_t, agi_magicnum), offsetof(xfs_agi_t, agi_versionnum), offsetof(xfs_agi_t, agi_seqno), offsetof(xfs_agi_t, agi_length), offsetof(xfs_agi_t, agi_count), offsetof(xfs_agi_t, agi_root), offsetof(xfs_agi_t, agi_level), offsetof(xfs_agi_t, agi_freecount), offsetof(xfs_agi_t, agi_newino), offsetof(xfs_agi_t, agi_dirino), offsetof(xfs_agi_t, agi_unlinked), sizeof(xfs_agi_t) }; #ifdef DEBUG xfs_agi_t *agi; /* allocation group header */ agi = XFS_BUF_TO_AGI(bp); ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC)); #endif /* * Compute byte offsets for the first and last fields. */ xfs_btree_offsets(fields, offsets, XFS_AGI_NUM_BITS, &first, &last); /* * Log the allocation group inode header buffer. */ xfs_trans_log_buf(tp, bp, first, last); } #ifdef DEBUG STATIC void xfs_check_agi_unlinked( struct xfs_agi *agi) { int i; for (i = 0; i < XFS_AGI_UNLINKED_BUCKETS; i++) ASSERT(agi->agi_unlinked[i]); } #else #define xfs_check_agi_unlinked(agi) #endif /* * Read in the allocation group header (inode allocation section) */ int xfs_read_agi( struct xfs_mount *mp, /* file system mount structure */ struct xfs_trans *tp, /* transaction pointer */ xfs_agnumber_t agno, /* allocation group number */ struct xfs_buf **bpp) /* allocation group hdr buf */ { struct xfs_agi *agi; /* allocation group header */ int agi_ok; /* agi is consistent */ int error; ASSERT(agno != NULLAGNUMBER); error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)), XFS_FSS_TO_BB(mp, 1), 0, bpp); if (error) return error; ASSERT(!xfs_buf_geterror(*bpp)); agi = XFS_BUF_TO_AGI(*bpp); /* * Validate the magic number of the agi block. */ agi_ok = agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC) && XFS_AGI_GOOD_VERSION(be32_to_cpu(agi->agi_versionnum)) && be32_to_cpu(agi->agi_seqno) == agno; if (unlikely(XFS_TEST_ERROR(!agi_ok, mp, XFS_ERRTAG_IALLOC_READ_AGI, XFS_RANDOM_IALLOC_READ_AGI))) { XFS_CORRUPTION_ERROR("xfs_read_agi", XFS_ERRLEVEL_LOW, mp, agi); xfs_trans_brelse(tp, *bpp); return XFS_ERROR(EFSCORRUPTED); } xfs_buf_set_ref(*bpp, XFS_AGI_REF); xfs_check_agi_unlinked(agi); return 0; } int xfs_ialloc_read_agi( struct xfs_mount *mp, /* file system mount structure */ struct xfs_trans *tp, /* transaction pointer */ xfs_agnumber_t agno, /* allocation group number */ struct xfs_buf **bpp) /* allocation group hdr buf */ { struct xfs_agi *agi; /* allocation group header */ struct xfs_perag *pag; /* per allocation group data */ int error; error = xfs_read_agi(mp, tp, agno, bpp); if (error) return error; agi = XFS_BUF_TO_AGI(*bpp); pag = xfs_perag_get(mp, agno); if (!pag->pagi_init) { pag->pagi_freecount = be32_to_cpu(agi->agi_freecount); pag->pagi_count = be32_to_cpu(agi->agi_count); pag->pagi_init = 1; } /* * It's possible for these to be out of sync if * we are in the middle of a forced shutdown. */ ASSERT(pag->pagi_freecount == be32_to_cpu(agi->agi_freecount) || XFS_FORCED_SHUTDOWN(mp)); xfs_perag_put(pag); return 0; } /* * Read in the agi to initialise the per-ag data in the mount structure */ int xfs_ialloc_pagi_init( xfs_mount_t *mp, /* file system mount structure */ xfs_trans_t *tp, /* transaction pointer */ xfs_agnumber_t agno) /* allocation group number */ { xfs_buf_t *bp = NULL; int error; error = xfs_ialloc_read_agi(mp, tp, agno, &bp); if (error) return error; if (bp) xfs_trans_brelse(tp, bp); return 0; }