diff options
Diffstat (limited to 'fs/xfs/xfs_bmap_util.c')
| -rw-r--r-- | fs/xfs/xfs_bmap_util.c | 834 |
1 files changed, 834 insertions, 0 deletions
diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c new file mode 100644 index 00000000000..8e48ddf1c11 --- /dev/null +++ b/fs/xfs/xfs_bmap_util.c @@ -0,0 +1,834 @@ +/* + * Copyright (c) 2000-2006 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_format.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_da_btree.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_extfree_item.h" +#include "xfs_alloc.h" +#include "xfs_bmap.h" +#include "xfs_bmap_util.h" +#include "xfs_rtalloc.h" +#include "xfs_error.h" +#include "xfs_quota.h" +#include "xfs_trans_space.h" +#include "xfs_trace.h" + +/* Kernel only BMAP related definitions and functions */ + +/* + * Convert the given file system block to a disk block. We have to treat it + * differently based on whether the file is a real time file or not, because the + * bmap code does. + */ +xfs_daddr_t +xfs_fsb_to_db(struct xfs_inode *ip, xfs_fsblock_t fsb) +{ + return (XFS_IS_REALTIME_INODE(ip) ? \ + (xfs_daddr_t)XFS_FSB_TO_BB((ip)->i_mount, (fsb)) : \ + XFS_FSB_TO_DADDR((ip)->i_mount, (fsb))); +} + +/* + * Routine to be called at transaction's end by xfs_bmapi, xfs_bunmapi + * caller. Frees all the extents that need freeing, which must be done + * last due to locking considerations. We never free any extents in + * the first transaction. + * + * Return 1 if the given transaction was committed and a new one + * started, and 0 otherwise in the committed parameter. + */ +int /* error */ +xfs_bmap_finish( + xfs_trans_t **tp, /* transaction pointer addr */ + xfs_bmap_free_t *flist, /* i/o: list extents to free */ + int *committed) /* xact committed or not */ +{ + xfs_efd_log_item_t *efd; /* extent free data */ + xfs_efi_log_item_t *efi; /* extent free intention */ + int error; /* error return value */ + xfs_bmap_free_item_t *free; /* free extent item */ + unsigned int logres; /* new log reservation */ + unsigned int logcount; /* new log count */ + xfs_mount_t *mp; /* filesystem mount structure */ + xfs_bmap_free_item_t *next; /* next item on free list */ + xfs_trans_t *ntp; /* new transaction pointer */ + + ASSERT((*tp)->t_flags & XFS_TRANS_PERM_LOG_RES); + if (flist->xbf_count == 0) { + *committed = 0; + return 0; + } + ntp = *tp; + efi = xfs_trans_get_efi(ntp, flist->xbf_count); + for (free = flist->xbf_first; free; free = free->xbfi_next) + xfs_trans_log_efi_extent(ntp, efi, free->xbfi_startblock, + free->xbfi_blockcount); + logres = ntp->t_log_res; + logcount = ntp->t_log_count; + ntp = xfs_trans_dup(*tp); + error = xfs_trans_commit(*tp, 0); + *tp = ntp; + *committed = 1; + /* + * We have a new transaction, so we should return committed=1, + * even though we're returning an error. + */ + if (error) + return error; + + /* + * transaction commit worked ok so we can drop the extra ticket + * reference that we gained in xfs_trans_dup() + */ + xfs_log_ticket_put(ntp->t_ticket); + + if ((error = xfs_trans_reserve(ntp, 0, logres, 0, XFS_TRANS_PERM_LOG_RES, + logcount))) + return error; + efd = xfs_trans_get_efd(ntp, efi, flist->xbf_count); + for (free = flist->xbf_first; free != NULL; free = next) { + next = free->xbfi_next; + if ((error = xfs_free_extent(ntp, free->xbfi_startblock, + free->xbfi_blockcount))) { + /* + * The bmap free list will be cleaned up at a + * higher level. The EFI will be canceled when + * this transaction is aborted. + * Need to force shutdown here to make sure it + * happens, since this transaction may not be + * dirty yet. + */ + mp = ntp->t_mountp; + if (!XFS_FORCED_SHUTDOWN(mp)) + xfs_force_shutdown(mp, + (error == EFSCORRUPTED) ? + SHUTDOWN_CORRUPT_INCORE : + SHUTDOWN_META_IO_ERROR); + return error; + } + xfs_trans_log_efd_extent(ntp, efd, free->xbfi_startblock, + free->xbfi_blockcount); + xfs_bmap_del_free(flist, NULL, free); + } + return 0; +} + +int +xfs_bmap_rtalloc( + struct xfs_bmalloca *ap) /* bmap alloc argument struct */ +{ + xfs_alloctype_t atype = 0; /* type for allocation routines */ + int error; /* error return value */ + xfs_mount_t *mp; /* mount point structure */ + xfs_extlen_t prod = 0; /* product factor for allocators */ + xfs_extlen_t ralen = 0; /* realtime allocation length */ + xfs_extlen_t align; /* minimum allocation alignment */ + xfs_rtblock_t rtb; + + mp = ap->ip->i_mount; + align = xfs_get_extsz_hint(ap->ip); + prod = align / mp->m_sb.sb_rextsize; + error = xfs_bmap_extsize_align(mp, &ap->got, &ap->prev, + align, 1, ap->eof, 0, + ap->conv, &ap->offset, &ap->length); + if (error) + return error; + ASSERT(ap->length); + ASSERT(ap->length % mp->m_sb.sb_rextsize == 0); + + /* + * If the offset & length are not perfectly aligned + * then kill prod, it will just get us in trouble. + */ + if (do_mod(ap->offset, align) || ap->length % align) + prod = 1; + /* + * Set ralen to be the actual requested length in rtextents. + */ + ralen = ap->length / mp->m_sb.sb_rextsize; + /* + * If the old value was close enough to MAXEXTLEN that + * we rounded up to it, cut it back so it's valid again. + * Note that if it's a really large request (bigger than + * MAXEXTLEN), we don't hear about that number, and can't + * adjust the starting point to match it. + */ + if (ralen * mp->m_sb.sb_rextsize >= MAXEXTLEN) + ralen = MAXEXTLEN / mp->m_sb.sb_rextsize; + + /* + * Lock out other modifications to the RT bitmap inode. + */ + xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL); + xfs_trans_ijoin(ap->tp, mp->m_rbmip, XFS_ILOCK_EXCL); + + /* + * If it's an allocation to an empty file at offset 0, + * pick an extent that will space things out in the rt area. + */ + if (ap->eof && ap->offset == 0) { + xfs_rtblock_t uninitialized_var(rtx); /* realtime extent no */ + + error = xfs_rtpick_extent(mp, ap->tp, ralen, &rtx); + if (error) + return error; + ap->blkno = rtx * mp->m_sb.sb_rextsize; + } else { + ap->blkno = 0; + } + + xfs_bmap_adjacent(ap); + + /* + * Realtime allocation, done through xfs_rtallocate_extent. + */ + atype = ap->blkno == 0 ? XFS_ALLOCTYPE_ANY_AG : XFS_ALLOCTYPE_NEAR_BNO; + do_div(ap->blkno, mp->m_sb.sb_rextsize); + rtb = ap->blkno; + ap->length = ralen; + if ((error = xfs_rtallocate_extent(ap->tp, ap->blkno, 1, ap->length, + &ralen, atype, ap->wasdel, prod, &rtb))) + return error; + if (rtb == NULLFSBLOCK && prod > 1 && + (error = xfs_rtallocate_extent(ap->tp, ap->blkno, 1, + ap->length, &ralen, atype, + ap->wasdel, 1, &rtb))) + return error; + ap->blkno = rtb; + if (ap->blkno != NULLFSBLOCK) { + ap->blkno *= mp->m_sb.sb_rextsize; + ralen *= mp->m_sb.sb_rextsize; + ap->length = ralen; + ap->ip->i_d.di_nblocks += ralen; + xfs_trans_log_inode(ap->tp, ap->ip, XFS_ILOG_CORE); + if (ap->wasdel) + ap->ip->i_delayed_blks -= ralen; + /* + * Adjust the disk quota also. This was reserved + * earlier. + */ + xfs_trans_mod_dquot_byino(ap->tp, ap->ip, + ap->wasdel ? XFS_TRANS_DQ_DELRTBCOUNT : + XFS_TRANS_DQ_RTBCOUNT, (long) ralen); + } else { + ap->length = 0; + } + return 0; +} + +/* + * Stack switching interfaces for allocation + */ +static void +xfs_bmapi_allocate_worker( + struct work_struct *work) +{ + struct xfs_bmalloca *args = container_of(work, + struct xfs_bmalloca, work); + unsigned long pflags; + + /* we are in a transaction context here */ + current_set_flags_nested(&pflags, PF_FSTRANS); + + args->result = __xfs_bmapi_allocate(args); + complete(args->done); + + current_restore_flags_nested(&pflags, PF_FSTRANS); +} + +/* + * Some allocation requests often come in with little stack to work on. Push + * them off to a worker thread so there is lots of stack to use. Otherwise just + * call directly to avoid the context switch overhead here. + */ +int +xfs_bmapi_allocate( + struct xfs_bmalloca *args) +{ + DECLARE_COMPLETION_ONSTACK(done); + + if (!args->stack_switch) + return __xfs_bmapi_allocate(args); + + + args->done = &done; + INIT_WORK_ONSTACK(&args->work, xfs_bmapi_allocate_worker); + queue_work(xfs_alloc_wq, &args->work); + wait_for_completion(&done); + return args->result; +} + +/* + * Check if the endoff is outside the last extent. If so the caller will grow + * the allocation to a stripe unit boundary. All offsets are considered outside + * the end of file for an empty fork, so 1 is returned in *eof in that case. + */ +int +xfs_bmap_eof( + struct xfs_inode *ip, + xfs_fileoff_t endoff, + int whichfork, + int *eof) +{ + struct xfs_bmbt_irec rec; + int error; + + error = xfs_bmap_last_extent(NULL, ip, whichfork, &rec, eof); + if (error || *eof) + return error; + + *eof = endoff >= rec.br_startoff + rec.br_blockcount; + return 0; +} + +/* + * Extent tree block counting routines. + */ + +/* + * Count leaf blocks given a range of extent records. + */ +STATIC void +xfs_bmap_count_leaves( + xfs_ifork_t *ifp, + xfs_extnum_t idx, + int numrecs, + int *count) +{ + int b; + + for (b = 0; b < numrecs; b++) { + xfs_bmbt_rec_host_t *frp = xfs_iext_get_ext(ifp, idx + b); + *count += xfs_bmbt_get_blockcount(frp); + } +} + +/* + * Count leaf blocks given a range of extent records originally + * in btree format. + */ +STATIC void +xfs_bmap_disk_count_leaves( + struct xfs_mount *mp, + struct xfs_btree_block *block, + int numrecs, + int *count) +{ + int b; + xfs_bmbt_rec_t *frp; + + for (b = 1; b <= numrecs; b++) { + frp = XFS_BMBT_REC_ADDR(mp, block, b); + *count += xfs_bmbt_disk_get_blockcount(frp); + } +} + +/* + * Recursively walks each level of a btree + * to count total fsblocks is use. + */ +STATIC int /* error */ +xfs_bmap_count_tree( + xfs_mount_t *mp, /* file system mount point */ + xfs_trans_t *tp, /* transaction pointer */ + xfs_ifork_t *ifp, /* inode fork pointer */ + xfs_fsblock_t blockno, /* file system block number */ + int levelin, /* level in btree */ + int *count) /* Count of blocks */ +{ + int error; + xfs_buf_t *bp, *nbp; + int level = levelin; + __be64 *pp; + xfs_fsblock_t bno = blockno; + xfs_fsblock_t nextbno; + struct xfs_btree_block *block, *nextblock; + int numrecs; + + error = xfs_btree_read_bufl(mp, tp, bno, 0, &bp, XFS_BMAP_BTREE_REF, + &xfs_bmbt_buf_ops); + if (error) + return error; + *count += 1; + block = XFS_BUF_TO_BLOCK(bp); + + if (--level) { + /* Not at node above leaves, count this level of nodes */ + nextbno = be64_to_cpu(block->bb_u.l.bb_rightsib); + while (nextbno != NULLFSBLOCK) { + error = xfs_btree_read_bufl(mp, tp, nextbno, 0, &nbp, + XFS_BMAP_BTREE_REF, + &xfs_bmbt_buf_ops); + if (error) + return error; + *count += 1; + nextblock = XFS_BUF_TO_BLOCK(nbp); + nextbno = be64_to_cpu(nextblock->bb_u.l.bb_rightsib); + xfs_trans_brelse(tp, nbp); + } + + /* Dive to the next level */ + pp = XFS_BMBT_PTR_ADDR(mp, block, 1, mp->m_bmap_dmxr[1]); + bno = be64_to_cpu(*pp); + if (unlikely((error = + xfs_bmap_count_tree(mp, tp, ifp, bno, level, count)) < 0)) { + xfs_trans_brelse(tp, bp); + XFS_ERROR_REPORT("xfs_bmap_count_tree(1)", + XFS_ERRLEVEL_LOW, mp); + return XFS_ERROR(EFSCORRUPTED); + } + xfs_trans_brelse(tp, bp); + } else { + /* count all level 1 nodes and their leaves */ + for (;;) { + nextbno = be64_to_cpu(block->bb_u.l.bb_rightsib); + numrecs = be16_to_cpu(block->bb_numrecs); + xfs_bmap_disk_count_leaves(mp, block, numrecs, count); + xfs_trans_brelse(tp, bp); + if (nextbno == NULLFSBLOCK) + break; + bno = nextbno; + error = xfs_btree_read_bufl(mp, tp, bno, 0, &bp, + XFS_BMAP_BTREE_REF, + &xfs_bmbt_buf_ops); + if (error) + return error; + *count += 1; + block = XFS_BUF_TO_BLOCK(bp); + } + } + return 0; +} + +/* + * Count fsblocks of the given fork. + */ +int /* error */ +xfs_bmap_count_blocks( + xfs_trans_t *tp, /* transaction pointer */ + xfs_inode_t *ip, /* incore inode */ + int whichfork, /* data or attr fork */ + int *count) /* out: count of blocks */ +{ + struct xfs_btree_block *block; /* current btree block */ + xfs_fsblock_t bno; /* block # of "block" */ + xfs_ifork_t *ifp; /* fork structure */ + int level; /* btree level, for checking */ + xfs_mount_t *mp; /* file system mount structure */ + __be64 *pp; /* pointer to block address */ + + bno = NULLFSBLOCK; + mp = ip->i_mount; + ifp = XFS_IFORK_PTR(ip, whichfork); + if ( XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS ) { + xfs_bmap_count_leaves(ifp, 0, + ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t), + count); + return 0; + } + + /* + * Root level must use BMAP_BROOT_PTR_ADDR macro to get ptr out. + */ + block = ifp->if_broot; + level = be16_to_cpu(block->bb_level); + ASSERT(level > 0); + pp = XFS_BMAP_BROOT_PTR_ADDR(mp, block, 1, ifp->if_broot_bytes); + bno = be64_to_cpu(*pp); + ASSERT(bno != NULLDFSBNO); + ASSERT(XFS_FSB_TO_AGNO(mp, bno) < mp->m_sb.sb_agcount); + ASSERT(XFS_FSB_TO_AGBNO(mp, bno) < mp->m_sb.sb_agblocks); + + if (unlikely(xfs_bmap_count_tree(mp, tp, ifp, bno, level, count) < 0)) { + XFS_ERROR_REPORT("xfs_bmap_count_blocks(2)", XFS_ERRLEVEL_LOW, + mp); + return XFS_ERROR(EFSCORRUPTED); + } + + return 0; +} + +/* + * returns 1 for success, 0 if we failed to map the extent. + */ +STATIC int +xfs_getbmapx_fix_eof_hole( + xfs_inode_t *ip, /* xfs incore inode pointer */ + struct getbmapx *out, /* output structure */ + int prealloced, /* this is a file with + * preallocated data space */ + __int64_t end, /* last block requested */ + xfs_fsblock_t startblock) +{ + __int64_t fixlen; + xfs_mount_t *mp; /* file system mount point */ + xfs_ifork_t *ifp; /* inode fork pointer */ + xfs_extnum_t lastx; /* last extent pointer */ + xfs_fileoff_t fileblock; + + if (startblock == HOLESTARTBLOCK) { + mp = ip->i_mount; + out->bmv_block = -1; + fixlen = XFS_FSB_TO_BB(mp, XFS_B_TO_FSB(mp, XFS_ISIZE(ip))); + fixlen -= out->bmv_offset; + if (prealloced && out->bmv_offset + out->bmv_length == end) { + /* Came to hole at EOF. Trim it. */ + if (fixlen <= 0) + return 0; + out->bmv_length = fixlen; + } + } else { + if (startblock == DELAYSTARTBLOCK) + out->bmv_block = -2; + else + out->bmv_block = xfs_fsb_to_db(ip, startblock); + fileblock = XFS_BB_TO_FSB(ip->i_mount, out->bmv_offset); + ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK); + if (xfs_iext_bno_to_ext(ifp, fileblock, &lastx) && + (lastx == (ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t))-1)) + out->bmv_oflags |= BMV_OF_LAST; + } + + return 1; +} + +/* + * Get inode's extents as described in bmv, and format for output. + * Calls formatter to fill the user's buffer until all extents + * are mapped, until the passed-in bmv->bmv_count slots have + * been filled, or until the formatter short-circuits the loop, + * if it is tracking filled-in extents on its own. + */ +int /* error code */ +xfs_getbmap( + xfs_inode_t *ip, + struct getbmapx *bmv, /* user bmap structure */ + xfs_bmap_format_t formatter, /* format to user */ + void *arg) /* formatter arg */ +{ + __int64_t bmvend; /* last block requested */ + int error = 0; /* return value */ + __int64_t fixlen; /* length for -1 case */ + int i; /* extent number */ + int lock; /* lock state */ + xfs_bmbt_irec_t *map; /* buffer for user's data */ + xfs_mount_t *mp; /* file system mount point */ + int nex; /* # of user extents can do */ + int nexleft; /* # of user extents left */ + int subnex; /* # of bmapi's can do */ + int nmap; /* number of map entries */ + struct getbmapx *out; /* output structure */ + int whichfork; /* data or attr fork */ + int prealloced; /* this is a file with + * preallocated data space */ + int iflags; /* interface flags */ + int bmapi_flags; /* flags for xfs_bmapi */ + int cur_ext = 0; + + mp = ip->i_mount; + iflags = bmv->bmv_iflags; + whichfork = iflags & BMV_IF_ATTRFORK ? XFS_ATTR_FORK : XFS_DATA_FORK; + + if (whichfork == XFS_ATTR_FORK) { + if (XFS_IFORK_Q(ip)) { + if (ip->i_d.di_aformat != XFS_DINODE_FMT_EXTENTS && + ip->i_d.di_aformat != XFS_DINODE_FMT_BTREE && + ip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL) + return XFS_ERROR(EINVAL); + } else if (unlikely( + ip->i_d.di_aformat != 0 && + ip->i_d.di_aformat != XFS_DINODE_FMT_EXTENTS)) { + XFS_ERROR_REPORT("xfs_getbmap", XFS_ERRLEVEL_LOW, + ip->i_mount); + return XFS_ERROR(EFSCORRUPTED); + } + + prealloced = 0; + fixlen = 1LL << 32; + } else { + if (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS && + ip->i_d.di_format != XFS_DINODE_FMT_BTREE && + ip->i_d.di_format != XFS_DINODE_FMT_LOCAL) + return XFS_ERROR(EINVAL); + + if (xfs_get_extsz_hint(ip) || + ip->i_d.di_flags & (XFS_DIFLAG_PREALLOC|XFS_DIFLAG_APPEND)){ + prealloced = 1; + fixlen = mp->m_super->s_maxbytes; + } else { + prealloced = 0; + fixlen = XFS_ISIZE(ip); + } + } + + if (bmv->bmv_length == -1) { + fixlen = XFS_FSB_TO_BB(mp, XFS_B_TO_FSB(mp, fixlen)); + bmv->bmv_length = + max_t(__int64_t, fixlen - bmv->bmv_offset, 0); + } else if (bmv->bmv_length == 0) { + bmv->bmv_entries = 0; + return 0; + } else if (bmv->bmv_length < 0) { + return XFS_ERROR(EINVAL); + } + + nex = bmv->bmv_count - 1; + if (nex <= 0) + return XFS_ERROR(EINVAL); + bmvend = bmv->bmv_offset + bmv->bmv_length; + + + if (bmv->bmv_count > ULONG_MAX / sizeof(struct getbmapx)) + return XFS_ERROR(ENOMEM); + out = kmem_zalloc(bmv->bmv_count * sizeof(struct getbmapx), KM_MAYFAIL); + if (!out) { + out = kmem_zalloc_large(bmv->bmv_count * + sizeof(struct getbmapx)); + if (!out) + return XFS_ERROR(ENOMEM); + } + + xfs_ilock(ip, XFS_IOLOCK_SHARED); + if (whichfork == XFS_DATA_FORK && !(iflags & BMV_IF_DELALLOC)) { + if (ip->i_delayed_blks || XFS_ISIZE(ip) > ip->i_d.di_size) { + error = -filemap_write_and_wait(VFS_I(ip)->i_mapping); + if (error) + goto out_unlock_iolock; + } + /* + * even after flushing the inode, there can still be delalloc + * blocks on the inode beyond EOF due to speculative + * preallocation. These are not removed until the release + * function is called or the inode is inactivated. Hence we + * cannot assert here that ip->i_delayed_blks == 0. + */ + } + + lock = xfs_ilock_map_shared(ip); + + /* + * Don't let nex be bigger than the number of extents + * we can have assuming alternating holes and real extents. + */ + if (nex > XFS_IFORK_NEXTENTS(ip, whichfork) * 2 + 1) + nex = XFS_IFORK_NEXTENTS(ip, whichfork) * 2 + 1; + + bmapi_flags = xfs_bmapi_aflag(whichfork); + if (!(iflags & BMV_IF_PREALLOC)) + bmapi_flags |= XFS_BMAPI_IGSTATE; + + /* + * Allocate enough space to handle "subnex" maps at a time. + */ + error = ENOMEM; + subnex = 16; + map = kmem_alloc(subnex * sizeof(*map), KM_MAYFAIL | KM_NOFS); + if (!map) + goto out_unlock_ilock; + + bmv->bmv_entries = 0; + + if (XFS_IFORK_NEXTENTS(ip, whichfork) == 0 && + (whichfork == XFS_ATTR_FORK || !(iflags & BMV_IF_DELALLOC))) { + error = 0; + goto out_free_map; + } + + nexleft = nex; + + do { + nmap = (nexleft > subnex) ? subnex : nexleft; + error = xfs_bmapi_read(ip, XFS_BB_TO_FSBT(mp, bmv->bmv_offset), + XFS_BB_TO_FSB(mp, bmv->bmv_length), + map, &nmap, bmapi_flags); + if (error) + goto out_free_map; + ASSERT(nmap <= subnex); + + for (i = 0; i < nmap && nexleft && bmv->bmv_length; i++) { + out[cur_ext].bmv_oflags = 0; + if (map[i].br_state == XFS_EXT_UNWRITTEN) + out[cur_ext].bmv_oflags |= BMV_OF_PREALLOC; + else if (map[i].br_startblock == DELAYSTARTBLOCK) + out[cur_ext].bmv_oflags |= BMV_OF_DELALLOC; + out[cur_ext].bmv_offset = + XFS_FSB_TO_BB(mp, map[i].br_startoff); + out[cur_ext].bmv_length = + XFS_FSB_TO_BB(mp, map[i].br_blockcount); + out[cur_ext].bmv_unused1 = 0; + out[cur_ext].bmv_unused2 = 0; + + /* + * delayed allocation extents that start beyond EOF can + * occur due to speculative EOF allocation when the + * delalloc extent is larger than the largest freespace + * extent at conversion time. These extents cannot be + * converted by data writeback, so can exist here even + * if we are not supposed to be finding delalloc + * extents. + */ + if (map[i].br_startblock == DELAYSTARTBLOCK && + map[i].br_startoff <= XFS_B_TO_FSB(mp, XFS_ISIZE(ip))) + ASSERT((iflags & BMV_IF_DELALLOC) != 0); + + if (map[i].br_startblock == HOLESTARTBLOCK && + whichfork == XFS_ATTR_FORK) { + /* came to the end of attribute fork */ + out[cur_ext].bmv_oflags |= BMV_OF_LAST; + goto out_free_map; + } + + if (!xfs_getbmapx_fix_eof_hole(ip, &out[cur_ext], + prealloced, bmvend, + map[i].br_startblock)) + goto out_free_map; + + bmv->bmv_offset = + out[cur_ext].bmv_offset + + out[cur_ext].bmv_length; + bmv->bmv_length = + max_t(__int64_t, 0, bmvend - bmv->bmv_offset); + + /* + * In case we don't want to return the hole, + * don't increase cur_ext so that we can reuse + * it in the next loop. + */ + if ((iflags & BMV_IF_NO_HOLES) && + map[i].br_startblock == HOLESTARTBLOCK) { + memset(&out[cur_ext], 0, sizeof(out[cur_ext])); + continue; + } + + nexleft--; + bmv->bmv_entries++; + cur_ext++; + } + } while (nmap && nexleft && bmv->bmv_length); + + out_free_map: + kmem_free(map); + out_unlock_ilock: + xfs_iunlock_map_shared(ip, lock); + out_unlock_iolock: + xfs_iunlock(ip, XFS_IOLOCK_SHARED); + + for (i = 0; i < cur_ext; i++) { + int full = 0; /* user array is full */ + + /* format results & advance arg */ + error = formatter(&arg, &out[i], &full); + if (error || full) + break; + } + + if (is_vmalloc_addr(out)) + kmem_free_large(out); + else + kmem_free(out); + return error; +} + +/* + * dead simple method of punching delalyed allocation blocks from a range in + * the inode. Walks a block at a time so will be slow, but is only executed in + * rare error cases so the overhead is not critical. This will alays punch out + * both the start and end blocks, even if the ranges only partially overlap + * them, so it is up to the caller to ensure that partial blocks are not + * passed in. + */ +int +xfs_bmap_punch_delalloc_range( + struct xfs_inode *ip, + xfs_fileoff_t start_fsb, + xfs_fileoff_t length) +{ + xfs_fileoff_t remaining = length; + int error = 0; + + ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL)); + + do { + int done; + xfs_bmbt_irec_t imap; + int nimaps = 1; + xfs_fsblock_t firstblock; + xfs_bmap_free_t flist; + + /* + * Map the range first and check that it is a delalloc extent + * before trying to unmap the range. Otherwise we will be + * trying to remove a real extent (which requires a + * transaction) or a hole, which is probably a bad idea... + */ + error = xfs_bmapi_read(ip, start_fsb, 1, &imap, &nimaps, + XFS_BMAPI_ENTIRE); + + if (error) { + /* something screwed, just bail */ + if (!XFS_FORCED_SHUTDOWN(ip->i_mount)) { + xfs_alert(ip->i_mount, + "Failed delalloc mapping lookup ino %lld fsb %lld.", + ip->i_ino, start_fsb); + } + break; + } + if (!nimaps) { + /* nothing there */ + goto next_block; + } + if (imap.br_startblock != DELAYSTARTBLOCK) { + /* been converted, ignore */ + goto next_block; + } + WARN_ON(imap.br_blockcount == 0); + + /* + * Note: while we initialise the firstblock/flist pair, they + * should never be used because blocks should never be + * allocated or freed for a delalloc extent and hence we need + * don't cancel or finish them after the xfs_bunmapi() call. + */ + xfs_bmap_init(&flist, &firstblock); + error = xfs_bunmapi(NULL, ip, start_fsb, 1, 0, 1, &firstblock, + &flist, &done); + if (error) + break; + + ASSERT(!flist.xbf_count && !flist.xbf_first); +next_block: + start_fsb++; + remaining--; + } while(remaining > 0); + + return error; +} |