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; }
/* * Cancel CoW reservations for some block range of an inode. * * If cancel_real is true this function cancels all COW fork extents for the * inode; if cancel_real is false, real extents are not cleared. */ int xfs_reflink_cancel_cow_blocks( struct xfs_inode *ip, struct xfs_trans **tpp, xfs_fileoff_t offset_fsb, xfs_fileoff_t end_fsb, bool cancel_real) { struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK); struct xfs_bmbt_irec got, del; xfs_extnum_t idx; xfs_fsblock_t firstfsb; struct xfs_defer_ops dfops; int error = 0; if (!xfs_is_reflink_inode(ip)) return 0; if (!xfs_iext_lookup_extent(ip, ifp, offset_fsb, &idx, &got)) return 0; while (got.br_startoff < end_fsb) { del = got; xfs_trim_extent(&del, offset_fsb, end_fsb - offset_fsb); trace_xfs_reflink_cancel_cow(ip, &del); if (isnullstartblock(del.br_startblock)) { error = xfs_bmap_del_extent_delay(ip, XFS_COW_FORK, &idx, &got, &del); if (error) break; } else if (del.br_state == XFS_EXT_UNWRITTEN || cancel_real) { xfs_trans_ijoin(*tpp, ip, 0); xfs_defer_init(&dfops, &firstfsb); /* Free the CoW orphan record. */ error = xfs_refcount_free_cow_extent(ip->i_mount, &dfops, del.br_startblock, del.br_blockcount); if (error) break; xfs_bmap_add_free(ip->i_mount, &dfops, del.br_startblock, del.br_blockcount, NULL); /* Update quota accounting */ xfs_trans_mod_dquot_byino(*tpp, ip, XFS_TRANS_DQ_BCOUNT, -(long)del.br_blockcount); /* Roll the transaction */ xfs_defer_ijoin(&dfops, ip); error = xfs_defer_finish(tpp, &dfops); if (error) { xfs_defer_cancel(&dfops); break; } /* Remove the mapping from the CoW fork. */ xfs_bmap_del_extent_cow(ip, &idx, &got, &del); } if (!xfs_iext_get_extent(ifp, ++idx, &got)) break; } /* clear tag if cow fork is emptied */ if (!ifp->if_bytes) xfs_inode_clear_cowblocks_tag(ip); return error; }
/* * Cancel CoW reservations for some block range of an inode. * * If cancel_real is true this function cancels all COW fork extents for the * inode; if cancel_real is false, real extents are not cleared. */ int xfs_reflink_cancel_cow_blocks( struct xfs_inode *ip, struct xfs_trans **tpp, xfs_fileoff_t offset_fsb, xfs_fileoff_t end_fsb, bool cancel_real) { struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK); struct xfs_bmbt_irec got, del; struct xfs_iext_cursor icur; xfs_fsblock_t firstfsb; struct xfs_defer_ops dfops; int error = 0; if (!xfs_is_reflink_inode(ip)) return 0; if (!xfs_iext_lookup_extent_before(ip, ifp, &end_fsb, &icur, &got)) return 0; /* Walk backwards until we're out of the I/O range... */ while (got.br_startoff + got.br_blockcount > offset_fsb) { del = got; xfs_trim_extent(&del, offset_fsb, end_fsb - offset_fsb); /* Extent delete may have bumped ext forward */ if (!del.br_blockcount) { xfs_iext_prev(ifp, &icur); goto next_extent; } trace_xfs_reflink_cancel_cow(ip, &del); if (isnullstartblock(del.br_startblock)) { error = xfs_bmap_del_extent_delay(ip, XFS_COW_FORK, &icur, &got, &del); if (error) break; } else if (del.br_state == XFS_EXT_UNWRITTEN || cancel_real) { xfs_trans_ijoin(*tpp, ip, 0); xfs_defer_init(&dfops, &firstfsb); /* Free the CoW orphan record. */ error = xfs_refcount_free_cow_extent(ip->i_mount, &dfops, del.br_startblock, del.br_blockcount); if (error) break; xfs_bmap_add_free(ip->i_mount, &dfops, del.br_startblock, del.br_blockcount, NULL); /* Update quota accounting */ xfs_trans_mod_dquot_byino(*tpp, ip, XFS_TRANS_DQ_BCOUNT, -(long)del.br_blockcount); /* Roll the transaction */ xfs_defer_ijoin(&dfops, ip); error = xfs_defer_finish(tpp, &dfops); if (error) { xfs_defer_cancel(&dfops); break; } /* Remove the mapping from the CoW fork. */ xfs_bmap_del_extent_cow(ip, &icur, &got, &del); } else { /* Didn't do anything, push cursor back. */ xfs_iext_prev(ifp, &icur); } next_extent: if (!xfs_iext_get_extent(ifp, &icur, &got)) break; } /* clear tag if cow fork is emptied */ if (!ifp->if_bytes) xfs_inode_clear_cowblocks_tag(ip); return error; }
/* * Unmap a range of blocks from a file, then map other blocks into the hole. * The range to unmap is (destoff : destoff + srcioff + irec->br_blockcount). * The extent irec is mapped into dest at irec->br_startoff. */ STATIC int xfs_reflink_remap_extent( struct xfs_inode *ip, struct xfs_bmbt_irec *irec, xfs_fileoff_t destoff, xfs_off_t new_isize) { struct xfs_mount *mp = ip->i_mount; bool real_extent = xfs_bmap_is_real_extent(irec); struct xfs_trans *tp; xfs_fsblock_t firstfsb; unsigned int resblks; struct xfs_defer_ops dfops; struct xfs_bmbt_irec uirec; xfs_filblks_t rlen; xfs_filblks_t unmap_len; xfs_off_t newlen; int error; unmap_len = irec->br_startoff + irec->br_blockcount - destoff; trace_xfs_reflink_punch_range(ip, destoff, unmap_len); /* No reflinking if we're low on space */ if (real_extent) { error = xfs_reflink_ag_has_free_space(mp, XFS_FSB_TO_AGNO(mp, irec->br_startblock)); if (error) goto out; } /* Start a rolling transaction to switch the mappings */ resblks = XFS_EXTENTADD_SPACE_RES(ip->i_mount, XFS_DATA_FORK); error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, 0, &tp); if (error) goto out; xfs_ilock(ip, XFS_ILOCK_EXCL); xfs_trans_ijoin(tp, ip, 0); /* If we're not just clearing space, then do we have enough quota? */ if (real_extent) { error = xfs_trans_reserve_quota_nblks(tp, ip, irec->br_blockcount, 0, XFS_QMOPT_RES_REGBLKS); if (error) goto out_cancel; } trace_xfs_reflink_remap(ip, irec->br_startoff, irec->br_blockcount, irec->br_startblock); /* Unmap the old blocks in the data fork. */ rlen = unmap_len; while (rlen) { xfs_defer_init(&dfops, &firstfsb); error = __xfs_bunmapi(tp, ip, destoff, &rlen, 0, 1, &firstfsb, &dfops); if (error) goto out_defer; /* * Trim the extent to whatever got unmapped. * Remember, bunmapi works backwards. */ uirec.br_startblock = irec->br_startblock + rlen; uirec.br_startoff = irec->br_startoff + rlen; uirec.br_blockcount = unmap_len - rlen; unmap_len = rlen; /* If this isn't a real mapping, we're done. */ if (!real_extent || uirec.br_blockcount == 0) goto next_extent; trace_xfs_reflink_remap(ip, uirec.br_startoff, uirec.br_blockcount, uirec.br_startblock); /* Update the refcount tree */ error = xfs_refcount_increase_extent(mp, &dfops, &uirec); if (error) goto out_defer; /* Map the new blocks into the data fork. */ error = xfs_bmap_map_extent(mp, &dfops, ip, &uirec); if (error) goto out_defer; /* Update quota accounting. */ xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, uirec.br_blockcount); /* Update dest isize if needed. */ newlen = XFS_FSB_TO_B(mp, uirec.br_startoff + uirec.br_blockcount); newlen = min_t(xfs_off_t, newlen, new_isize); if (newlen > i_size_read(VFS_I(ip))) { trace_xfs_reflink_update_inode_size(ip, newlen); i_size_write(VFS_I(ip), newlen); ip->i_d.di_size = newlen; xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); } next_extent: /* Process all the deferred stuff. */ xfs_defer_ijoin(&dfops, ip); error = xfs_defer_finish(&tp, &dfops); if (error) goto out_defer; } error = xfs_trans_commit(tp); xfs_iunlock(ip, XFS_ILOCK_EXCL); if (error) goto out; return 0; out_defer: xfs_defer_cancel(&dfops); out_cancel: xfs_trans_cancel(tp); xfs_iunlock(ip, XFS_ILOCK_EXCL); out: trace_xfs_reflink_remap_extent_error(ip, error, _RET_IP_); return error; }
/* * Remap part of the CoW fork into the data fork. * * We aim to remap the range starting at @offset_fsb and ending at @end_fsb * into the data fork; this function will remap what it can (at the end of the * range) and update @end_fsb appropriately. Each remap gets its own * transaction because we can end up merging and splitting bmbt blocks for * every remap operation and we'd like to keep the block reservation * requirements as low as possible. */ STATIC int xfs_reflink_end_cow_extent( struct xfs_inode *ip, xfs_fileoff_t offset_fsb, xfs_fileoff_t *end_fsb) { struct xfs_bmbt_irec got, del; struct xfs_iext_cursor icur; struct xfs_mount *mp = ip->i_mount; struct xfs_trans *tp; struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK); xfs_filblks_t rlen; unsigned int resblks; int error; /* No COW extents? That's easy! */ if (ifp->if_bytes == 0) { *end_fsb = offset_fsb; return 0; } resblks = XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK); error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, XFS_TRANS_RESERVE | XFS_TRANS_NOFS, &tp); if (error) return error; /* * Lock the inode. We have to ijoin without automatic unlock because * the lead transaction is the refcountbt record deletion; the data * fork update follows as a deferred log item. */ xfs_ilock(ip, XFS_ILOCK_EXCL); xfs_trans_ijoin(tp, ip, 0); /* * In case of racing, overlapping AIO writes no COW extents might be * left by the time I/O completes for the loser of the race. In that * case we are done. */ if (!xfs_iext_lookup_extent_before(ip, ifp, end_fsb, &icur, &got) || got.br_startoff + got.br_blockcount <= offset_fsb) { *end_fsb = offset_fsb; goto out_cancel; } /* * Structure copy @got into @del, then trim @del to the range that we * were asked to remap. We preserve @got for the eventual CoW fork * deletion; from now on @del represents the mapping that we're * actually remapping. */ del = got; xfs_trim_extent(&del, offset_fsb, *end_fsb - offset_fsb); ASSERT(del.br_blockcount > 0); /* * Only remap real extents that contain data. With AIO, speculative * preallocations can leak into the range we are called upon, and we * need to skip them. */ if (!xfs_bmap_is_real_extent(&got)) { *end_fsb = del.br_startoff; goto out_cancel; } /* Unmap the old blocks in the data fork. */ rlen = del.br_blockcount; error = __xfs_bunmapi(tp, ip, del.br_startoff, &rlen, 0, 1); if (error) goto out_cancel; /* Trim the extent to whatever got unmapped. */ xfs_trim_extent(&del, del.br_startoff + rlen, del.br_blockcount - rlen); trace_xfs_reflink_cow_remap(ip, &del); /* Free the CoW orphan record. */ error = xfs_refcount_free_cow_extent(tp, del.br_startblock, del.br_blockcount); if (error) goto out_cancel; /* Map the new blocks into the data fork. */ error = xfs_bmap_map_extent(tp, ip, &del); if (error) goto out_cancel; /* Charge this new data fork mapping to the on-disk quota. */ xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_DELBCOUNT, (long)del.br_blockcount); /* Remove the mapping from the CoW fork. */ xfs_bmap_del_extent_cow(ip, &icur, &got, &del); error = xfs_trans_commit(tp); xfs_iunlock(ip, XFS_ILOCK_EXCL); if (error) return error; /* Update the caller about how much progress we made. */ *end_fsb = del.br_startoff; return 0; out_cancel: xfs_trans_cancel(tp); xfs_iunlock(ip, XFS_ILOCK_EXCL); return error; }