diff options
Diffstat (limited to 'fs/xfs/xfs_bmap_util.c')
| -rw-r--r-- | fs/xfs/xfs_bmap_util.c | 2026 |
1 files changed, 2026 insertions, 0 deletions
diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c new file mode 100644 index 000000000000..541d59f5e658 --- /dev/null +++ b/fs/xfs/xfs_bmap_util.c @@ -0,0 +1,2026 @@ +/* + * Copyright (c) 2000-2006 Silicon Graphics, Inc. + * Copyright (c) 2012 Red Hat, 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" +#include "xfs_icache.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 */ + struct xfs_trans_res tres; /* new log reservation */ + 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); + + tres.tr_logres = ntp->t_log_res; + tres.tr_logcount = ntp->t_log_count; + tres.tr_logflags = XFS_TRANS_PERM_LOG_RES; + 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); + + error = xfs_trans_reserve(ntp, &tres, 0, 0); + if (error) + 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 in 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 always 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; +} + +/* + * Test whether it is appropriate to check an inode for and free post EOF + * blocks. The 'force' parameter determines whether we should also consider + * regular files that are marked preallocated or append-only. + */ +bool +xfs_can_free_eofblocks(struct xfs_inode *ip, bool force) +{ + /* prealloc/delalloc exists only on regular files */ + if (!S_ISREG(ip->i_d.di_mode)) + return false; + + /* + * Zero sized files with no cached pages and delalloc blocks will not + * have speculative prealloc/delalloc blocks to remove. + */ + if (VFS_I(ip)->i_size == 0 && + VN_CACHED(VFS_I(ip)) == 0 && + ip->i_delayed_blks == 0) + return false; + + /* If we haven't read in the extent list, then don't do it now. */ + if (!(ip->i_df.if_flags & XFS_IFEXTENTS)) + return false; + + /* + * Do not free real preallocated or append-only files unless the file + * has delalloc blocks and we are forced to remove them. + */ + if (ip->i_d.di_flags & (XFS_DIFLAG_PREALLOC | XFS_DIFLAG_APPEND)) + if (!force || ip->i_delayed_blks == 0) + return false; + + return true; +} + +/* + * This is called by xfs_inactive to free any blocks beyond eof + * when the link count isn't zero and by xfs_dm_punch_hole() when + * punching a hole to EOF. + */ +int +xfs_free_eofblocks( + xfs_mount_t *mp, + xfs_inode_t *ip, + bool need_iolock) +{ + xfs_trans_t *tp; + int error; + xfs_fileoff_t end_fsb; + xfs_fileoff_t last_fsb; + xfs_filblks_t map_len; + int nimaps; + xfs_bmbt_irec_t imap; + + /* + * Figure out if there are any blocks beyond the end + * of the file. If not, then there is nothing to do. + */ + end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)XFS_ISIZE(ip)); + last_fsb = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes); + if (last_fsb <= end_fsb) + return 0; + map_len = last_fsb - end_fsb; + + nimaps = 1; + xfs_ilock(ip, XFS_ILOCK_SHARED); + error = xfs_bmapi_read(ip, end_fsb, map_len, &imap, &nimaps, 0); + xfs_iunlock(ip, XFS_ILOCK_SHARED); + + if (!error && (nimaps != 0) && + (imap.br_startblock != HOLESTARTBLOCK || + ip->i_delayed_blks)) { + /* + * Attach the dquots to the inode up front. + */ + error = xfs_qm_dqattach(ip, 0); + if (error) + return error; + + /* + * There are blocks after the end of file. + * Free them up now by truncating the file to + * its current size. + */ + tp = xfs_trans_alloc(mp, XFS_TRANS_INACTIVE); + + if (need_iolock) { + if (!xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL)) { + xfs_trans_cancel(tp, 0); + return EAGAIN; + } + } + + error = xfs_trans_reserve(tp, &M_RES(mp)->tr_itruncate, 0, 0); + if (error) { + ASSERT(XFS_FORCED_SHUTDOWN(mp)); + xfs_trans_cancel(tp, 0); + if (need_iolock) + xfs_iunlock(ip, XFS_IOLOCK_EXCL); + return error; + } + + xfs_ilock(ip, XFS_ILOCK_EXCL); + xfs_trans_ijoin(tp, ip, 0); + + /* + * Do not update the on-disk file size. If we update the + * on-disk file size and then the system crashes before the + * contents of the file are flushed to disk then the files + * may be full of holes (ie NULL files bug). + */ + error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK, + XFS_ISIZE(ip)); + if (error) { + /* + * If we get an error at this point we simply don't + * bother truncating the file. + */ + xfs_trans_cancel(tp, + (XFS_TRANS_RELEASE_LOG_RES | + XFS_TRANS_ABORT)); + } else { + error = xfs_trans_commit(tp, + XFS_TRANS_RELEASE_LOG_RES); + if (!error) + xfs_inode_clear_eofblocks_tag(ip); + } + + xfs_iunlock(ip, XFS_ILOCK_EXCL); + if (need_iolock) + xfs_iunlock(ip, XFS_IOLOCK_EXCL); + } + return error; +} + +/* + * xfs_alloc_file_space() + * This routine allocates disk space for the given file. + * + * If alloc_type == 0, this request is for an ALLOCSP type + * request which will change the file size. In this case, no + * DMAPI event will be generated by the call. A TRUNCATE event + * will be generated later by xfs_setattr. + * + * If alloc_type != 0, this request is for a RESVSP type + * request, and a DMAPI DM_EVENT_WRITE will be generated if the + * lower block boundary byte address is less than the file's + * length. + * + * RETURNS: + * 0 on success + * errno on error + * + */ +STATIC int +xfs_alloc_file_space( + xfs_inode_t *ip, + xfs_off_t offset, + xfs_off_t len, + int alloc_type, + int attr_flags) +{ + xfs_mount_t *mp = ip->i_mount; + xfs_off_t count; + xfs_filblks_t allocated_fsb; + xfs_filblks_t allocatesize_fsb; + xfs_extlen_t extsz, temp; + xfs_fileoff_t startoffset_fsb; + xfs_fsblock_t firstfsb; + int nimaps; + int quota_flag; + int rt; + xfs_trans_t *tp; + xfs_bmbt_irec_t imaps[1], *imapp; + xfs_bmap_free_t free_list; + uint qblocks, resblks, resrtextents; + int committed; + int error; + + trace_xfs_alloc_file_space(ip); + + if (XFS_FORCED_SHUTDOWN(mp)) + return XFS_ERROR(EIO); + + error = xfs_qm_dqattach(ip, 0); + if (error) + return error; + + if (len <= 0) + return XFS_ERROR(EINVAL); + + rt = XFS_IS_REALTIME_INODE(ip); + extsz = xfs_get_extsz_hint(ip); + + count = len; + imapp = &imaps[0]; + nimaps = 1; + startoffset_fsb = XFS_B_TO_FSBT(mp, offset); + allocatesize_fsb = XFS_B_TO_FSB(mp, count); + + /* + * Allocate file space until done or until there is an error + */ + while (allocatesize_fsb && !error) { + xfs_fileoff_t s, e; + + /* + * Determine space reservations for data/realtime. + */ + if (unlikely(extsz)) { + s = startoffset_fsb; + do_div(s, extsz); + s *= extsz; + e = startoffset_fsb + allocatesize_fsb; + if ((temp = do_mod(startoffset_fsb, extsz))) + e += temp; + if ((temp = do_mod(e, extsz))) + e += extsz - temp; + } else { + s = 0; + e = allocatesize_fsb; + } + + /* + * The transaction reservation is limited to a 32-bit block + * count, hence we need to limit the number of blocks we are + * trying to reserve to avoid an overflow. We can't allocate + * more than @nimaps extents, and an extent is limited on disk + * to MAXEXTLEN (21 bits), so use that to enforce the limit. + */ + resblks = min_t(xfs_fileoff_t, (e - s), (MAXEXTLEN * nimaps)); + if (unlikely(rt)) { + resrtextents = qblocks = resblks; + resrtextents /= mp->m_sb.sb_rextsize; + resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0); + quota_flag = XFS_QMOPT_RES_RTBLKS; + } else { + resrtextents = 0; + resblks = qblocks = XFS_DIOSTRAT_SPACE_RES(mp, resblks); + quota_flag = XFS_QMOPT_RES_REGBLKS; + } + + /* + * Allocate and setup the transaction. + */ + tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT); + error = xfs_trans_reserve(tp, &M_RES(mp)->tr_write, + resblks, resrtextents); + /* + * Check for running out of space + */ + if (error) { + /* + * Free the transaction structure. + */ + ASSERT(error == ENOSPC || XFS_FORCED_SHUTDOWN(mp)); + xfs_trans_cancel(tp, 0); + break; + } + xfs_ilock(ip, XFS_ILOCK_EXCL); + error = xfs_trans_reserve_quota_nblks(tp, ip, qblocks, + 0, quota_flag); + if (error) + goto error1; + + xfs_trans_ijoin(tp, ip, 0); + + xfs_bmap_init(&free_list, &firstfsb); + error = xfs_bmapi_write(tp, ip, startoffset_fsb, + allocatesize_fsb, alloc_type, &firstfsb, + 0, imapp, &nimaps, &free_list); + if (error) { + goto error0; + } + + /* + * Complete the transaction + */ + error = xfs_bmap_finish(&tp, &free_list, &committed); + if (error) { + goto error0; + } + + error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES); + xfs_iunlock(ip, XFS_ILOCK_EXCL); + if (error) { + break; + } + + allocated_fsb = imapp->br_blockcount; + + if (nimaps == 0) { + error = XFS_ERROR(ENOSPC); + break; + } + + startoffset_fsb += allocated_fsb; + allocatesize_fsb -= allocated_fsb; + } + + return error; + +error0: /* Cancel bmap, unlock inode, unreserve quota blocks, cancel trans */ + xfs_bmap_cancel(&free_list); + xfs_trans_unreserve_quota_nblks(tp, ip, (long)qblocks, 0, quota_flag); + +error1: /* Just cancel transaction */ + xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT); + xfs_iunlock(ip, XFS_ILOCK_EXCL); + return error; +} + +/* + * Zero file bytes between startoff and endoff inclusive. + * The iolock is held exclusive and no blocks are buffered. + * + * This function is used by xfs_free_file_space() to zero + * partial blocks when the range to free is not block aligned. + * When unreserving space with boundaries that are not block + * aligned we round up the start and round down the end + * boundaries and then use this function to zero the parts of + * the blocks that got dropped during the rounding. + */ +STATIC int +xfs_zero_remaining_bytes( + xfs_inode_t *ip, + xfs_off_t startoff, + xfs_off_t endoff) +{ + xfs_bmbt_irec_t imap; + xfs_fileoff_t offset_fsb; + xfs_off_t lastoffset; + xfs_off_t offset; + xfs_buf_t *bp; + xfs_mount_t *mp = ip->i_mount; + int nimap; + int error = 0; + + /* + * Avoid doing I/O beyond eof - it's not necessary + * since nothing can read beyond eof. The space will + * be zeroed when the file is extended anyway. + */ + if (startoff >= XFS_ISIZE(ip)) + return 0; + + if (endoff > XFS_ISIZE(ip)) + endoff = XFS_ISIZE(ip); + + bp = xfs_buf_get_uncached(XFS_IS_REALTIME_INODE(ip) ? + mp->m_rtdev_targp : mp->m_ddev_targp, + BTOBB(mp->m_sb.sb_blocksize), 0); + if (!bp) + return XFS_ERROR(ENOMEM); + + xfs_buf_unlock(bp); + + for (offset = startoff; offset <= endoff; offset = lastoffset + 1) { + offset_fsb = XFS_B_TO_FSBT(mp, offset); + nimap = 1; + error = xfs_bmapi_read(ip, offset_fsb, 1, &imap, &nimap, 0); + if (error || nimap < 1) + break; + ASSERT(imap.br_blockcount >= 1); + ASSERT(imap.br_startoff == offset_fsb); + lastoffset = XFS_FSB_TO_B(mp, imap.br_startoff + 1) - 1; + if (lastoffset > endoff) + lastoffset = endoff; + if (imap.br_startblock == HOLESTARTBLOCK) + continue; + ASSERT(imap.br_startblock != DELAYSTARTBLOCK); + if (imap.br_state == XFS_EXT_UNWRITTEN) + continue; + XFS_BUF_UNDONE(bp); + XFS_BUF_UNWRITE(bp); + XFS_BUF_READ(bp); + XFS_BUF_SET_ADDR(bp, xfs_fsb_to_db(ip, imap.br_startblock)); + xfsbdstrat(mp, bp); + error = xfs_buf_iowait(bp); + if (error) { + xfs_buf_ioerror_alert(bp, + "xfs_zero_remaining_bytes(read)"); + break; + } + memset(bp->b_addr + + (offset - XFS_FSB_TO_B(mp, imap.br_startoff)), + 0, lastoffset - offset + 1); + XFS_BUF_UNDONE(bp); + XFS_BUF_UNREAD(bp); + XFS_BUF_WRITE(bp); + xfsbdstrat(mp, bp); + error = xfs_buf_iowait(bp); + if (error) { + xfs_buf_ioerror_alert(bp, + "xfs_zero_remaining_bytes(write)"); + break; + } + } + xfs_buf_free(bp); + return error; +} + +/* + * xfs_free_file_space() + * This routine frees disk space for the given file. + * + * This routine is only called by xfs_change_file_space + * for an UNRESVSP type call. + * + * RETURNS: + * 0 on success + * errno on error + * + */ +STATIC int +xfs_free_file_space( + xfs_inode_t *ip, + xfs_off_t offset, + xfs_off_t len, + int attr_flags) +{ + int committed; + int done; + xfs_fileoff_t endoffset_fsb; + int error; + xfs_fsblock_t firstfsb; + xfs_bmap_free_t free_list; + xfs_bmbt_irec_t imap; + xfs_off_t ioffset; + xfs_extlen_t mod=0; + xfs_mount_t *mp; + int nimap; + uint resblks; + xfs_off_t rounding; + int rt; + xfs_fileoff_t startoffset_fsb; + xfs_trans_t *tp; + int need_iolock = 1; + + mp = ip->i_mount; + + trace_xfs_free_file_space(ip); + + error = xfs_qm_dqattach(ip, 0); + if (error) + return error; + + error = 0; + if (len <= 0) /* if nothing being freed */ + return error; + rt = XFS_IS_REALTIME_INODE(ip); + startoffset_fsb = XFS_B_TO_FSB(mp, offset); + endoffset_fsb = XFS_B_TO_FSBT(mp, offset + len); + + if (attr_flags & XFS_ATTR_NOLOCK) + need_iolock = 0; + if (need_iolock) { + xfs_ilock(ip, XFS_IOLOCK_EXCL); + /* wait for the completion of any pending DIOs */ + inode_dio_wait(VFS_I(ip)); + } + + rounding = max_t(xfs_off_t, 1 << mp->m_sb.sb_blocklog, PAGE_CACHE_SIZE); + ioffset = offset & ~(rounding - 1); + error = -filemap_write_and_wait_range(VFS_I(ip)->i_mapping, + ioffset, -1); + if (error) + goto out_unlock_iolock; + truncate_pagecache_range(VFS_I(ip), ioffset, -1); + + /* + * Need to zero the stuff we're not freeing, on disk. + * If it's a realtime file & can't use unwritten extents then we + * actually need to zero the extent edges. Otherwise xfs_bunmapi + * will take care of it for us. + */ + if (rt && !xfs_sb_version_hasextflgbit(&mp->m_sb)) { + nimap = 1; + error = xfs_bmapi_read(ip, startoffset_fsb, 1, + &imap, &nimap, 0); + if (error) + goto out_unlock_iolock; + ASSERT(nimap == 0 || nimap == 1); + if (nimap && imap.br_startblock != HOLESTARTBLOCK) { + xfs_daddr_t block; + + ASSERT(imap.br_startblock != DELAYSTARTBLOCK); + block = imap.br_startblock; + mod = do_div(block, mp->m_sb.sb_rextsize); + if (mod) + startoffset_fsb += mp->m_sb.sb_rextsize - mod; + } + nimap = 1; + error = xfs_bmapi_read(ip, endoffset_fsb - 1, 1, + &imap, &nimap, 0); + if (error) + goto out_unlock_iolock; + ASSERT(nimap == 0 || nimap == 1); + if (nimap && imap.br_startblock != HOLESTARTBLOCK) { + ASSERT(imap.br_startblock != DELAYSTARTBLOCK); + mod++; + if (mod && (mod != mp->m_sb.sb_rextsize)) + endoffset_fsb -= mod; + } + } + if ((done = (endoffset_fsb <= startoffset_fsb))) + /* + * One contiguous piece to clear + */ + error = xfs_zero_remaining_bytes(ip, offset, offset + len - 1); + else { + /* + * Some full blocks, possibly two pieces to clear + */ + if (offset < XFS_FSB_TO_B(mp, startoffset_fsb)) + error = xfs_zero_remaining_bytes(ip, offset, + XFS_FSB_TO_B(mp, startoffset_fsb) - 1); + if (!error && + XFS_FSB_TO_B(mp, endoffset_fsb) < offset + len) + error = xfs_zero_remaining_bytes(ip, + XFS_FSB_TO_B(mp, endoffset_fsb), + offset + len - 1); + } + + /* + * free file space until done or until there is an error + */ + resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0); + while (!error && !done) { + + /* + * allocate and setup the transaction. Allow this + * transaction to dip into the reserve blocks to ensure + * the freeing of the space succeeds at ENOSPC. + */ + tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT); + tp->t_flags |= XFS_TRANS_RESERVE; + error = xfs_trans_reserve(tp, &M_RES(mp)->tr_write, resblks, 0); + + /* + * check for running out of space + */ + if (error) { + /* + * Free the transaction structure. + */ + ASSERT(error == ENOSPC || XFS_FORCED_SHUTDOWN(mp)); + xfs_trans_cancel(tp, 0); + break; + } + xfs_ilock(ip, XFS_ILOCK_EXCL); + error = xfs_trans_reserve_quota(tp, mp, + ip->i_udquot, ip->i_gdquot, ip->i_pdquot, + resblks, 0, XFS_QMOPT_RES_REGBLKS); + if (error) + goto error1; + + xfs_trans_ijoin(tp, ip, 0); + + /* + * issue the bunmapi() call to free the blocks + */ + xfs_bmap_init(&free_list, &firstfsb); + error = xfs_bunmapi(tp, ip, startoffset_fsb, + endoffset_fsb - startoffset_fsb, + 0, 2, &firstfsb, &free_list, &done); + if (error) { + goto error0; + } + + /* + * complete the transaction + */ + error = xfs_bmap_finish(&tp, &free_list, &committed); + if (error) { + goto error0; + } + + error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES); + xfs_iunlock(ip, XFS_ILOCK_EXCL); + } + + out_unlock_iolock: + if (need_iolock) + xfs_iunlock(ip, XFS_IOLOCK_EXCL); + return error; + + error0: + xfs_bmap_cancel(&free_list); + error1: + xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT); + xfs_iunlock(ip, need_iolock ? (XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL) : + XFS_ILOCK_EXCL); + return error; +} + + +STATIC int +xfs_zero_file_space( + struct xfs_inode *ip, + xfs_off_t offset, + xfs_off_t len, + int attr_flags) +{ + struct xfs_mount *mp = ip->i_mount; + uint granularity; + xfs_off_t start_boundary; + xfs_off_t end_boundary; + int error; + + granularity = max_t(uint, 1 << mp->m_sb.sb_blocklog, PAGE_CACHE_SIZE); + + /* + * Round the range of extents we are going to convert inwards. If the + * offset is aligned, then it doesn't get changed so we zero from the + * start of the block offset points to. + */ + start_boundary = round_up(offset, granularity); + end_boundary = round_down(offset + len, granularity); + + ASSERT(start_boundary >= offset); + ASSERT(end_boundary <= offset + len); + + if (!(attr_flags & XFS_ATTR_NOLOCK)) + xfs_ilock(ip, XFS_IOLOCK_EXCL); + + if (start_boundary < end_boundary - 1) { + /* punch out the page cache over the conversion range */ + truncate_pagecache_range(VFS_I(ip), start_boundary, + end_boundary - 1); + /* convert the blocks */ + error = xfs_alloc_file_space(ip, start_boundary, + end_boundary - start_boundary - 1, + XFS_BMAPI_PREALLOC | XFS_BMAPI_CONVERT, + attr_flags); + if (error) + goto out_unlock; + + /* We've handled the interior of the range, now for the edges */ + if (start_boundary != offset) + error = xfs_iozero(ip, offset, start_boundary - offset); + if (error) + goto out_unlock; + + if (end_boundary != offset + len) + error = xfs_iozero(ip, end_boundary, + offset + len - end_boundary); + + } else { + /* + * It's either a sub-granularity range or the range spanned lies + * partially across two adjacent blocks. + */ + error = xfs_iozero(ip, offset, len); + } + +out_unlock: + if (!(attr_flags & XFS_ATTR_NOLOCK)) + xfs_iunlock(ip, XFS_IOLOCK_EXCL); + return error; + +} + +/* + * xfs_change_file_space() + * This routine allocates or frees disk space for the given file. + * The user specified parameters are checked for alignment and size + * limitations. + * + * RETURNS: + * 0 on success + * errno on error + * + */ +int +xfs_change_file_space( + xfs_inode_t *ip, + int cmd, + xfs_flock64_t *bf, + xfs_off_t offset, + int attr_flags) +{ + xfs_mount_t *mp = ip->i_mount; + int clrprealloc; + int error; + xfs_fsize_t fsize; + int setprealloc; + xfs_off_t startoffset; + xfs_trans_t *tp; + struct iattr iattr; + + if (!S_ISREG(ip->i_d.di_mode)) + return XFS_ERROR(EINVAL); + + switch (bf->l_whence) { + case 0: /*SEEK_SET*/ + break; + case 1: /*SEEK_CUR*/ + bf->l_start += offset; + break; + case 2: /*SEEK_END*/ + bf->l_start += XFS_ISIZE(ip); + break; + default: + return XFS_ERROR(EINVAL); + } + + /* + * length of <= 0 for resv/unresv/zero is invalid. length for + * alloc/free is ignored completely and we have no idea what userspace + * might have set it to, so set it to zero to allow range + * checks to pass. + */ + switch (cmd) { + case XFS_IOC_ZERO_RANGE: + case XFS_IOC_RESVSP: + case XFS_IOC_RESVSP64: + case XFS_IOC_UNRESVSP: + case XFS_IOC_UNRESVSP64: + if (bf->l_len <= 0) + return XFS_ERROR(EINVAL); + break; + default: + bf->l_len = 0; + break; + } + + if (bf->l_start < 0 || + bf->l_start > mp->m_super->s_maxbytes || + bf->l_start + bf->l_len < 0 || + bf->l_start + bf->l_len >= mp->m_super->s_maxbytes) + return XFS_ERROR(EINVAL); + + bf->l_whence = 0; + + startoffset = bf->l_start; + fsize = XFS_ISIZE(ip); + + setprealloc = clrprealloc = 0; + switch (cmd) { + case XFS_IOC_ZERO_RANGE: + error = xfs_zero_file_space(ip, startoffset, bf->l_len, + attr_flags); + if (error) + return error; + setprealloc = 1; + break; + + case XFS_IOC_RESVSP: + case XFS_IOC_RESVSP64: + error = xfs_alloc_file_space(ip, startoffset, bf->l_len, + XFS_BMAPI_PREALLOC, attr_flags); + if (error) + return error; + setprealloc = 1; + break; + + case XFS_IOC_UNRESVSP: + case XFS_IOC_UNRESVSP64: + if ((error = xfs_free_file_space(ip, startoffset, bf->l_len, + attr_flags))) + return error; + break; + + case XFS_IOC_ALLOCSP: + case XFS_IOC_ALLOCSP64: + case XFS_IOC_FREESP: + case XFS_IOC_FREESP64: + /* + * These operations actually do IO when extending the file, but + * the allocation is done seperately to the zeroing that is + * done. This set of operations need to be serialised against + * other IO operations, such as truncate and buffered IO. We + * need to take the IOLOCK here to serialise the allocation and + * zeroing IO to prevent other IOLOCK holders (e.g. getbmap, + * truncate, direct IO) from racing against the transient + * allocated but not written state we can have here. + */ + xfs_ilock(ip, XFS_IOLOCK_EXCL); + if (startoffset > fsize) { + error = xfs_alloc_file_space(ip, fsize, + startoffset - fsize, 0, + attr_flags | XFS_ATTR_NOLOCK); + if (error) { + xfs_iunlock(ip, XFS_IOLOCK_EXCL); + break; + } + } + + iattr.ia_valid = ATTR_SIZE; + iattr.ia_size = startoffset; + + error = xfs_setattr_size(ip, &iattr, + attr_flags | XFS_ATTR_NOLOCK); + xfs_iunlock(ip, XFS_IOLOCK_EXCL); + + if (error) + return error; + + clrprealloc = 1; + break; + + default: + ASSERT(0); + return XFS_ERROR(EINVAL); + } + + /* + * update the inode timestamp, mode, and prealloc flag bits + */ + tp = xfs_trans_alloc(mp, XFS_TRANS_WRITEID); + error = xfs_trans_reserve(tp, &M_RES(mp)->tr_writeid, 0, 0); + if (error) { + xfs_trans_cancel(tp, 0); + return error; + } + + xfs_ilock(ip, XFS_ILOCK_EXCL); + xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL); + + if ((attr_flags & XFS_ATTR_DMI) == 0) { + ip->i_d.di_mode &= ~S_ISUID; + + /* + * Note that we don't have to worry about mandatory + * file locking being disabled here because we only + * clear the S_ISGID bit if the Group execute bit is + * on, but if it was on then mandatory locking wouldn't + * have been enabled. + */ + if (ip->i_d.di_mode & S_IXGRP) + ip->i_d.di_mode &= ~S_ISGID; + + xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); + } + if (setprealloc) + ip->i_d.di_flags |= XFS_DIFLAG_PREALLOC; + else if (clrprealloc) + ip->i_d.di_flags &= ~XFS_DIFLAG_PREALLOC; + + xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); + if (attr_flags & XFS_ATTR_SYNC) + xfs_trans_set_sync(tp); + return xfs_trans_commit(tp, 0); +} + +/* + * We need to check that the format of the data fork in the temporary inode is + * valid for the target inode before doing the swap. This is not a problem with + * attr1 because of the fixed fork offset, but attr2 has a dynamically sized + * data fork depending on the space the attribute fork is taking so we can get + * invalid formats on the target inode. + * + * E.g. target has space for 7 extents in extent format, temp inode only has + * space for 6. If we defragment down to 7 extents, then the tmp format is a + * btree, but when swapped it needs to be in extent format. Hence we can't just + * blindly swap data forks on attr2 filesystems. + * + * Note that we check the swap in both directions so that we don't end up with + * a corrupt temporary inode, either. + * + * Note that fixing the way xfs_fsr sets up the attribute fork in the source + * inode will prevent this situation from occurring, so all we do here is + * reject and log the attempt. basically we are putting the responsibility on + * userspace to get this right. + */ +static int +xfs_swap_extents_check_format( + xfs_inode_t *ip, /* target inode */ + xfs_inode_t *tip) /* tmp inode */ +{ + + /* Should never get a local format */ + if (ip->i_d.di_format == XFS_DINODE_FMT_LOCAL || + tip->i_d.di_format == XFS_DINODE_FMT_LOCAL) + return EINVAL; + + /* + * if the target inode has less extents that then temporary inode then + * why did userspace call us? + */ + if (ip->i_d.di_nextents < tip->i_d.di_nextents) + return EINVAL; + + /* + * if the target inode is in extent form and the temp inode is in btree + * form then we will end up with the target inode in the wrong format + * as we already know there are less extents in the temp inode. + */ + if (ip->i_d.di_format == XFS_DINODE_FMT_EXTENTS && + tip->i_d.di_format == XFS_DINODE_FMT_BTREE) + return EINVAL; + + /* Check temp in extent form to max in target */ + if (tip->i_d.di_format == XFS_DINODE_FMT_EXTENTS && + XFS_IFORK_NEXTENTS(tip, XFS_DATA_FORK) > + XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK)) + return EINVAL; + + /* Check target in extent form to max in temp */ + if (ip->i_d.di_format == XFS_DINODE_FMT_EXTENTS && + XFS_IFORK_NEXTENTS(ip, XFS_DATA_FORK) > + XFS_IFORK_MAXEXT(tip, XFS_DATA_FORK)) + return EINVAL; + + /* + * If we are in a btree format, check that the temp root block will fit + * in the target and that it has enough extents to be in btree format + * in the target. + * + * Note that we have to be careful to allow btree->extent conversions + * (a common defrag case) which will occur when the temp inode is in + * extent format... + */ + if (tip->i_d.di_format == XFS_DINODE_FMT_BTREE) { + if (XFS_IFORK_BOFF(ip) && + XFS_BMAP_BMDR_SPACE(tip->i_df.if_broot) > XFS_IFORK_BOFF(ip)) + return EINVAL; + if (XFS_IFORK_NEXTENTS(tip, XFS_DATA_FORK) <= + XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK)) + return EINVAL; + } + + /* Reciprocal target->temp btree format checks */ + if (ip->i_d.di_format == XFS_DINODE_FMT_BTREE) { + if (XFS_IFORK_BOFF(tip) && + XFS_BMAP_BMDR_SPACE(ip->i_df.if_broot) > XFS_IFORK_BOFF(tip)) + return EINVAL; + if (XFS_IFORK_NEXTENTS(ip, XFS_DATA_FORK) <= + XFS_IFORK_MAXEXT(tip, XFS_DATA_FORK)) + return EINVAL; + } + + return 0; +} + +int +xfs_swap_extents( + xfs_inode_t *ip, /* target inode */ + xfs_inode_t *tip, /* tmp inode */ + xfs_swapext_t *sxp) +{ + xfs_mount_t *mp = ip->i_mount; + xfs_trans_t *tp; + xfs_bstat_t *sbp = &sxp->sx_stat; + xfs_ifork_t *tempifp, *ifp, *tifp; + int src_log_flags, target_log_flags; + int error = 0; + int aforkblks = 0; + int taforkblks = 0; + __uint64_t tmp; + + /* + * We have no way of updating owner information in the BMBT blocks for + * each inode on CRC enabled filesystems, so to avoid corrupting the + * this metadata we simply don't allow extent swaps to occur. + */ + if (xfs_sb_version_hascrc(&mp->m_sb)) + return XFS_ERROR(EINVAL); + + tempifp = kmem_alloc(sizeof(xfs_ifork_t), KM_MAYFAIL); + if (!tempifp) { + error = XFS_ERROR(ENOMEM); + goto out; + } + + /* + * we have to do two separate lock calls here to keep lockdep + * happy. If we try to get all the locks in one call, lock will + * report false positives when we drop the ILOCK and regain them + * below. + */ + xfs_lock_two_inodes(ip, tip, XFS_IOLOCK_EXCL); + xfs_lock_two_inodes(ip, tip, XFS_ILOCK_EXCL); + + /* Verify that both files have the same format */ + if ((ip->i_d.di_mode & S_IFMT) != (tip->i_d.di_mode & S_IFMT)) { + error = XFS_ERROR(EINVAL); + goto out_unlock; + } + + /* Verify both files are either real-time or non-realtime */ + if (XFS_IS_REALTIME_INODE(ip) != XFS_IS_REALTIME_INODE(tip)) { + error = XFS_ERROR(EINVAL); + goto out_unlock; + } + + error = -filemap_write_and_wait(VFS_I(tip)->i_mapping); + if (error) + goto out_unlock; + truncate_pagecache_range(VFS_I(tip), 0, -1); + + /* Verify O_DIRECT for ftmp */ + if (VN_CACHED(VFS_I(tip)) != 0) { + error = XFS_ERROR(EINVAL); + goto out_unlock; + } + + /* Verify all data are being swapped */ + if (sxp->sx_offset != 0 || + sxp->sx_length != ip->i_d.di_size || + sxp->sx_length != tip->i_d.di_size) { + error = XFS_ERROR(EFAULT); + goto out_unlock; + } + + trace_xfs_swap_extent_before(ip, 0); + trace_xfs_swap_extent_before(tip, 1); + + /* check inode formats now that data is flushed */ + error = xfs_swap_extents_check_format(ip, tip); + if (error) { + xfs_notice(mp, + "%s: inode 0x%llx format is incompatible for exchanging.", + __func__, ip->i_ino); + goto out_unlock; + } + + /* + * Compare the current change & modify times with that + * passed in. If they differ, we abort this swap. + * This is the mechanism used to ensure the calling + * process that the file was not changed out from + * under it. + */ + if ((sbp->bs_ctime.tv_sec != VFS_I(ip)->i_ctime.tv_sec) || + (sbp->bs_ctime.tv_nsec != VFS_I(ip)->i_ctime.tv_nsec) || + (sbp->bs_mtime.tv_sec != VFS_I(ip)->i_mtime.tv_sec) || + (sbp->bs_mtime.tv_nsec != VFS_I(ip)->i_mtime.tv_nsec)) { + error = XFS_ERROR(EBUSY); + goto out_unlock; + } + + /* We need to fail if the file is memory mapped. Once we have tossed + * all existing pages, the page fault will have no option + * but to go to the filesystem for pages. By making the page fault call + * vop_read (or write in the case of autogrow) they block on the iolock + * until we have switched the extents. + */ + if (VN_MAPPED(VFS_I(ip))) { + error = XFS_ERROR(EBUSY); + goto out_unlock; + } + + xfs_iunlock(ip, XFS_ILOCK_EXCL); + xfs_iunlock(tip, XFS_ILOCK_EXCL); + + /* + * There is a race condition here since we gave up the + * ilock. However, the data fork will not change since + * we have the iolock (locked for truncation too) so we + * are safe. We don't really care if non-io related + * fields change. + */ + truncate_pagecache_range(VFS_I(ip), 0, -1); + + tp = xfs_trans_alloc(mp, XFS_TRANS_SWAPEXT); + error = xfs_trans_reserve(tp, &M_RES(mp)->tr_ichange, 0, 0); + if (error) { + xfs_iunlock(ip, XFS_IOLOCK_EXCL); + xfs_iunlock(tip, XFS_IOLOCK_EXCL); + xfs_trans_cancel(tp, 0); + goto out; + } + xfs_lock_two_inodes(ip, tip, XFS_ILOCK_EXCL); + + /* + * Count the number of extended attribute blocks + */ + if ( ((XFS_IFORK_Q(ip) != 0) && (ip->i_d.di_anextents > 0)) && + (ip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)) { + error = xfs_bmap_count_blocks(tp, ip, XFS_ATTR_FORK, &aforkblks); + if (error) + goto out_trans_cancel; + } + if ( ((XFS_IFORK_Q(tip) != 0) && (tip->i_d.di_anextents > 0)) && + (tip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)) { + error = xfs_bmap_count_blocks(tp, tip, XFS_ATTR_FORK, + &taforkblks); + if (error) + goto out_trans_cancel; + } + + /* + * Swap the data forks of the inodes + */ + ifp = &ip->i_df; + tifp = &tip->i_df; + *tempifp = *ifp; /* struct copy */ + *ifp = *tifp; /* struct copy */ + *tifp = *tempifp; /* struct copy */ + + /* + * Fix the on-disk inode values + */ + tmp = (__uint64_t)ip->i_d.di_nblocks; + ip->i_d.di_nblocks = tip->i_d.di_nblocks - taforkblks + aforkblks; + tip->i_d.di_nblocks = tmp + taforkblks - aforkblks; + + tmp = (__uint64_t) ip->i_d.di_nextents; + ip->i_d.di_nextents = tip->i_d.di_nextents; + tip->i_d.di_nextents = tmp; + + tmp = (__uint64_t) ip->i_d.di_format; + ip->i_d.di_format = tip->i_d.di_format; + tip->i_d.di_format = tmp; + + /* + * The extents in the source inode could still contain speculative + * preallocation beyond EOF (e.g. the file is open but not modified + * while defrag is in progress). In that case, we need to copy over the + * number of delalloc blocks the data fork in the source inode is + * tracking beyond EOF so that when the fork is truncated away when the + * temporary inode is unlinked we don't underrun the i_delayed_blks + * counter on that inode. + */ + ASSERT(tip->i_delayed_blks == 0); + tip->i_delayed_blks = ip->i_delayed_blks; + ip->i_delayed_blks = 0; + + src_log_flags = XFS_ILOG_CORE; + switch (ip->i_d.di_format) { + case XFS_DINODE_FMT_EXTENTS: + /* If the extents fit in the inode, fix the + * pointer. Otherwise it's already NULL or + * pointing to the extent. + */ + if (ip->i_d.di_nextents <= XFS_INLINE_EXTS) { + ifp->if_u1.if_extents = + ifp->if_u2.if_inline_ext; + } + src_log_flags |= XFS_ILOG_DEXT; + break; + case XFS_DINODE_FMT_BTREE: + src_log_flags |= XFS_ILOG_DBROOT; + break; + } + + target_log_flags = XFS_ILOG_CORE; + switch (tip->i_d.di_format) { + case XFS_DINODE_FMT_EXTENTS: + /* If the extents fit in the inode, fix the + * pointer. Otherwise it's already NULL or + * pointing to the extent. + */ + if (tip->i_d.di_nextents <= XFS_INLINE_EXTS) { + tifp->if_u1.if_extents = + tifp->if_u2.if_inline_ext; + } + target_log_flags |= XFS_ILOG_DEXT; + break; + case XFS_DINODE_FMT_BTREE: + target_log_flags |= XFS_ILOG_DBROOT; + break; + } + + + xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL); + xfs_trans_ijoin(tp, tip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL); + + xfs_trans_log_inode(tp, ip, src_log_flags); + xfs_trans_log_inode(tp, tip, target_log_flags); + + /* + * If this is a synchronous mount, make sure that the + * transaction goes to disk before returning to the user. + */ + if (mp->m_flags & XFS_MOUNT_WSYNC) + xfs_trans_set_sync(tp); + + error = xfs_trans_commit(tp, 0); + + trace_xfs_swap_extent_after(ip, 0); + trace_xfs_swap_extent_after(tip, 1); +out: + kmem_free(tempifp); + return error; + +out_unlock: + xfs_iunlock(ip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL); + xfs_iunlock(tip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL); + goto out; + +out_trans_cancel: + xfs_trans_cancel(tp, 0); + goto out_unlock; +} |