/* * We are now using libxfs for our IO backend, so we should always try to use * inode cluster buffers rather than filesystem block sized buffers for reading * inodes. This means that we always use the same buffers as libxfs operations * does, and that avoids buffer cache issues caused by overlapping buffers. This * can be seen clearly when trying to read the root inode. Much of this logic is * similar to libxfs_imap(). */ void set_cur_inode( xfs_ino_t ino) { xfs_agblock_t agbno; xfs_agino_t agino; xfs_agnumber_t agno; xfs_dinode_t *dip; int offset; int numblks = blkbb; xfs_agblock_t cluster_agbno; agno = XFS_INO_TO_AGNO(mp, ino); agino = XFS_INO_TO_AGINO(mp, ino); agbno = XFS_AGINO_TO_AGBNO(mp, agino); offset = XFS_AGINO_TO_OFFSET(mp, agino); if (agno >= mp->m_sb.sb_agcount || agbno >= mp->m_sb.sb_agblocks || offset >= mp->m_sb.sb_inopblock || XFS_AGINO_TO_INO(mp, agno, agino) != ino) { dbprintf(_("bad inode number %lld\n"), ino); return; } cur_agno = agno; if (mp->m_inode_cluster_size > mp->m_sb.sb_blocksize && mp->m_inoalign_mask) { xfs_agblock_t chunk_agbno; xfs_agblock_t offset_agbno; int blks_per_cluster; blks_per_cluster = mp->m_inode_cluster_size >> mp->m_sb.sb_blocklog; offset_agbno = agbno & mp->m_inoalign_mask; chunk_agbno = agbno - offset_agbno; cluster_agbno = chunk_agbno + ((offset_agbno / blks_per_cluster) * blks_per_cluster); offset += ((agbno - cluster_agbno) * mp->m_sb.sb_inopblock); numblks = XFS_FSB_TO_BB(mp, blks_per_cluster); } else
int xfs_agino_to_offset(xfs_mount_t *mp, xfs_agino_t i) { return XFS_AGINO_TO_OFFSET(mp, i); }
/* * Allocate an inode on disk. * Mode is used to tell whether the new inode will need space, and whether * it is a directory. * * The arguments IO_agbp and alloc_done are defined to work within * the constraint of one allocation per transaction. * xfs_dialloc() 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, * i.e., xfs_dialloc() did not need to do an allocation, an inode * number is returned. In this case, IO_agbp would be set to the * current ag_buf and alloc_done set to false. * If an allocation needed to be done, xfs_dialloc would return * the current ag_buf in IO_agbp and set alloc_done to true. * 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 agbp 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( xfs_trans_t *tp, /* transaction pointer */ xfs_ino_t parent, /* parent inode (directory) */ mode_t mode, /* mode bits for new inode */ int okalloc, /* ok to allocate more space */ xfs_buf_t **IO_agbp, /* in/out ag header's buffer */ boolean_t *alloc_done, /* true if we needed to replenish inode freelist */ xfs_ino_t *inop) /* inode number allocated */ { xfs_agnumber_t agcount; /* number of allocation groups */ xfs_buf_t *agbp; /* allocation group header's buffer */ xfs_agnumber_t agno; /* allocation group number */ xfs_agi_t *agi; /* allocation group header structure */ xfs_btree_cur_t *cur; /* inode allocation btree cursor */ int error; /* error return value */ int i; /* result code */ int ialloced; /* inode allocation status */ int noroom = 0; /* no space for inode blk allocation */ xfs_ino_t ino; /* fs-relative inode to be returned */ /* REFERENCED */ int j; /* result code */ xfs_mount_t *mp; /* file system mount structure */ int offset; /* index of inode in chunk */ xfs_agino_t pagino; /* parent's a.g. relative inode # */ xfs_agnumber_t pagno; /* parent's allocation group number */ xfs_inobt_rec_incore_t rec; /* inode allocation record */ xfs_agnumber_t tagno; /* testing allocation group number */ xfs_btree_cur_t *tcur; /* temp cursor */ xfs_inobt_rec_incore_t trec; /* temp inode allocation record */ if (*IO_agbp == NULL) { /* * 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); ASSERT(be32_to_cpu(agi->agi_magicnum) == XFS_AGI_MAGIC); } else { /* * Continue where we left off before. In this case, we * know that the allocation group has free inodes. */ agbp = *IO_agbp; agi = XFS_BUF_TO_AGI(agbp); ASSERT(be32_to_cpu(agi->agi_magicnum) == XFS_AGI_MAGIC); ASSERT(be32_to_cpu(agi->agi_freecount) > 0); } mp = tp->t_mountp; agcount = mp->m_sb.sb_agcount; agno = be32_to_cpu(agi->agi_seqno); tagno = agno; pagno = XFS_INO_TO_AGNO(mp, parent); pagino = XFS_INO_TO_AGINO(mp, parent); /* * 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. */ *alloc_done = B_FALSE; 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); *alloc_done = B_TRUE; *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 == agcount) tagno = 0; if (tagno == agno) { *inop = NULLFSINO; return noroom ? ENOSPC : 0; } down_read(&mp->m_peraglock); if (mp->m_perag[tagno].pagi_inodeok == 0) { up_read(&mp->m_peraglock); goto nextag; } error = xfs_ialloc_read_agi(mp, tp, tagno, &agbp); up_read(&mp->m_peraglock); if (error) goto nextag; agi = XFS_BUF_TO_AGI(agbp); ASSERT(be32_to_cpu(agi->agi_magicnum) == XFS_AGI_MAGIC); } /* * Here with an allocation group that has a free inode. * Reset agno since we may have chosen a new ag in the * loop above. */ agno = tagno; *IO_agbp = NULL; cur = xfs_btree_init_cursor(mp, tp, agbp, be32_to_cpu(agi->agi_seqno), XFS_BTNUM_INO, (xfs_inode_t *)0, 0); /* * 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); #ifdef DEBUG if (cur->bc_nlevels == 1) { int freecount = 0; if ((error = xfs_inobt_lookup_ge(cur, 0, 0, 0, &i))) goto error0; XFS_WANT_CORRUPTED_GOTO(i == 1, error0); do { if ((error = xfs_inobt_get_rec(cur, &rec.ir_startino, &rec.ir_freecount, &rec.ir_free, &i))) goto error0; XFS_WANT_CORRUPTED_GOTO(i == 1, error0); freecount += rec.ir_freecount; if ((error = xfs_inobt_increment(cur, 0, &i))) goto error0; } while (i == 1); ASSERT(freecount == be32_to_cpu(agi->agi_freecount) || XFS_FORCED_SHUTDOWN(mp)); } #endif /* * If in the same a.g. as the parent, try to get near the parent. */ if (pagno == agno) { if ((error = xfs_inobt_lookup_le(cur, pagino, 0, 0, &i))) goto error0; if (i != 0 && (error = xfs_inobt_get_rec(cur, &rec.ir_startino, &rec.ir_freecount, &rec.ir_free, &j)) == 0 && j == 1 && rec.ir_freecount > 0) { /* * Found a free inode in the same chunk * as parent, done. */ } /* * In the same a.g. as parent, but parent's chunk is full. */ else { int doneleft; /* done, to the left */ int doneright; /* done, to the right */ if (error) goto error0; ASSERT(i == 1); ASSERT(j == 1); /* * Duplicate the cursor, search left & right * simultaneously. */ if ((error = xfs_btree_dup_cursor(cur, &tcur))) goto error0; /* * Search left with tcur, back up 1 record. */ if ((error = xfs_inobt_decrement(tcur, 0, &i))) goto error1; doneleft = !i; if (!doneleft) { if ((error = xfs_inobt_get_rec(tcur, &trec.ir_startino, &trec.ir_freecount, &trec.ir_free, &i))) goto error1; XFS_WANT_CORRUPTED_GOTO(i == 1, error1); } /* * Search right with cur, go forward 1 record. */ if ((error = xfs_inobt_increment(cur, 0, &i))) goto error1; doneright = !i; if (!doneright) { if ((error = xfs_inobt_get_rec(cur, &rec.ir_startino, &rec.ir_freecount, &rec.ir_free, &i))) goto error1; XFS_WANT_CORRUPTED_GOTO(i == 1, error1); } /* * Loop until we find the closest inode chunk * with a free one. */ while (!doneleft || !doneright) { int useleft; /* using left inode chunk this time */ /* * Figure out which block is closer, * if both are valid. */ if (!doneleft && !doneright) useleft = pagino - (trec.ir_startino + XFS_INODES_PER_CHUNK - 1) < rec.ir_startino - pagino; else useleft = !doneleft; /* * If checking the left, does it have * free inodes? */ if (useleft && trec.ir_freecount) { /* * Yes, set it up as the chunk to use. */ rec = trec; xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR); cur = tcur; break; } /* * If checking the right, does it have * free inodes? */ if (!useleft && rec.ir_freecount) { /* * Yes, it's already set up. */ xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR); break; } /* * If used the left, get another one * further left. */ if (useleft) { if ((error = xfs_inobt_decrement(tcur, 0, &i))) goto error1; doneleft = !i; if (!doneleft) { if ((error = xfs_inobt_get_rec( tcur, &trec.ir_startino, &trec.ir_freecount, &trec.ir_free, &i))) goto error1; XFS_WANT_CORRUPTED_GOTO(i == 1, error1); } } /* * If used the right, get another one * further right. */ else { if ((error = xfs_inobt_increment(cur, 0, &i))) goto error1; doneright = !i; if (!doneright) { if ((error = xfs_inobt_get_rec( cur, &rec.ir_startino, &rec.ir_freecount, &rec.ir_free, &i))) goto error1; XFS_WANT_CORRUPTED_GOTO(i == 1, error1); } } } ASSERT(!doneleft || !doneright); } } /* * In a different a.g. from the parent. * See if the most recently allocated block has any free. */ else if (be32_to_cpu(agi->agi_newino) != NULLAGINO) { if ((error = xfs_inobt_lookup_eq(cur, be32_to_cpu(agi->agi_newino), 0, 0, &i))) goto error0; if (i == 1 && (error = xfs_inobt_get_rec(cur, &rec.ir_startino, &rec.ir_freecount, &rec.ir_free, &j)) == 0 && j == 1 && rec.ir_freecount > 0) { /* * The last chunk allocated in the group still has * a free inode. */ } /* * None left in the last group, search the whole a.g. */ else { if (error) goto error0; if ((error = xfs_inobt_lookup_ge(cur, 0, 0, 0, &i))) goto error0; ASSERT(i == 1); for (;;) { if ((error = xfs_inobt_get_rec(cur, &rec.ir_startino, &rec.ir_freecount, &rec.ir_free, &i))) goto error0; XFS_WANT_CORRUPTED_GOTO(i == 1, error0); if (rec.ir_freecount > 0) break; if ((error = xfs_inobt_increment(cur, 0, &i))) goto error0; XFS_WANT_CORRUPTED_GOTO(i == 1, error0); } } } offset = XFS_IALLOC_FIND_FREE(&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); XFS_INOBT_CLR_FREE(&rec, offset); rec.ir_freecount--; if ((error = xfs_inobt_update(cur, rec.ir_startino, rec.ir_freecount, rec.ir_free))) goto error0; be32_add_cpu(&agi->agi_freecount, -1); xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT); down_read(&mp->m_peraglock); mp->m_perag[tagno].pagi_freecount--; up_read(&mp->m_peraglock); #ifdef DEBUG if (cur->bc_nlevels == 1) { int freecount = 0; if ((error = xfs_inobt_lookup_ge(cur, 0, 0, 0, &i))) goto error0; do { if ((error = xfs_inobt_get_rec(cur, &rec.ir_startino, &rec.ir_freecount, &rec.ir_free, &i))) goto error0; XFS_WANT_CORRUPTED_GOTO(i == 1, error0); freecount += rec.ir_freecount; if ((error = xfs_inobt_increment(cur, 0, &i))) goto error0; } while (i == 1); ASSERT(freecount == be32_to_cpu(agi->agi_freecount) || XFS_FORCED_SHUTDOWN(mp)); } #endif xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR); xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -1); *inop = ino; return 0; error1: xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR); error0: xfs_btree_del_cursor(cur, XFS_BTREE_ERROR); 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. * * The arguments IO_agbp and alloc_done are defined to work within * the constraint of one allocation per transaction. * xfs_dialloc() 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, * i.e., xfs_dialloc() did not need to do an allocation, an inode * number is returned. In this case, IO_agbp would be set to the * current ag_buf and alloc_done set to false. * If an allocation needed to be done, xfs_dialloc would return * the current ag_buf in IO_agbp and set alloc_done to true. * 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 agbp 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( xfs_trans_t *tp, /* transaction pointer */ xfs_ino_t parent, /* parent inode (directory) */ umode_t mode, /* mode bits for new inode */ int okalloc, /* ok to allocate more space */ xfs_buf_t **IO_agbp, /* in/out ag header's buffer */ boolean_t *alloc_done, /* true if we needed to replenish inode freelist */ xfs_ino_t *inop) /* inode number allocated */ { xfs_agnumber_t agcount; /* number of allocation groups */ xfs_buf_t *agbp; /* allocation group header's buffer */ xfs_agnumber_t agno; /* allocation group number */ xfs_agi_t *agi; /* allocation group header structure */ xfs_btree_cur_t *cur; /* inode allocation btree cursor */ int error; /* error return value */ int i; /* result code */ int ialloced; /* inode allocation status */ int noroom = 0; /* no space for inode blk allocation */ xfs_ino_t ino; /* fs-relative inode to be returned */ /* REFERENCED */ int j; /* result code */ xfs_mount_t *mp; /* file system mount structure */ int offset; /* index of inode in chunk */ xfs_agino_t pagino; /* parent's AG relative inode # */ xfs_agnumber_t pagno; /* parent's AG number */ xfs_inobt_rec_incore_t rec; /* inode allocation record */ xfs_agnumber_t tagno; /* testing allocation group number */ xfs_btree_cur_t *tcur; /* temp cursor */ xfs_inobt_rec_incore_t trec; /* temp inode allocation record */ struct xfs_perag *pag; if (*IO_agbp == NULL) { /* * 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); ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC)); } else { /* * Continue where we left off before. In this case, we * know that the allocation group has free inodes. */ agbp = *IO_agbp; agi = XFS_BUF_TO_AGI(agbp); ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC)); ASSERT(be32_to_cpu(agi->agi_freecount) > 0); } mp = tp->t_mountp; agcount = mp->m_sb.sb_agcount; agno = be32_to_cpu(agi->agi_seqno); tagno = agno; pagno = XFS_INO_TO_AGNO(mp, parent); pagino = XFS_INO_TO_AGINO(mp, parent); /* * 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. */ *alloc_done = B_FALSE; 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); *alloc_done = B_TRUE; *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 == 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)); } /* * Here with an allocation group that has a free inode. * Reset agno since we may have chosen a new ag in the * loop above. */ agno = tagno; *IO_agbp = NULL; pag = xfs_perag_get(mp, agno); restart_pagno: cur = xfs_inobt_init_cursor(mp, tp, agbp, be32_to_cpu(agi->agi_seqno)); /* * 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_ialloc_find_free(&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. * * 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); if (error) goto error1; error = xfs_ialloc_get_rec(cur, pag->pagl_rightrec, &rec, &doneright); 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; }