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author | Kevin | 2014-11-15 09:58:27 +0800 |
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committer | Kevin | 2014-11-15 09:58:27 +0800 |
commit | 392e8802486cb573b916e746010e141a75f507e6 (patch) | |
tree | 50029aca02c81f087b90336e670b44e510782330 /ANDROID_3.4.5/fs/xfs/xfs_ialloc.c | |
download | FOSSEE-netbook-kernel-source-392e8802486cb573b916e746010e141a75f507e6.tar.gz FOSSEE-netbook-kernel-source-392e8802486cb573b916e746010e141a75f507e6.tar.bz2 FOSSEE-netbook-kernel-source-392e8802486cb573b916e746010e141a75f507e6.zip |
init android origin source code
Diffstat (limited to 'ANDROID_3.4.5/fs/xfs/xfs_ialloc.c')
-rw-r--r-- | ANDROID_3.4.5/fs/xfs/xfs_ialloc.c | 1565 |
1 files changed, 1565 insertions, 0 deletions
diff --git a/ANDROID_3.4.5/fs/xfs/xfs_ialloc.c b/ANDROID_3.4.5/fs/xfs/xfs_ialloc.c new file mode 100644 index 00000000..dad1a31a --- /dev/null +++ b/ANDROID_3.4.5/fs/xfs/xfs_ialloc.c @@ -0,0 +1,1565 @@ +/* + * 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, + XBF_LOCK); + 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; +} + +/* + * Visible inode allocation functions. + */ + +/* + * 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; +} + +/* + * 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; +} |