From 0293ce3a9fd1b34c933a96577a8ba737b681cf75 Mon Sep 17 00:00:00 2001 From: Mandy Kirkconnell Date: Tue, 14 Mar 2006 13:30:23 +1100 Subject: [XFS] 929045 567344 This mod introduces multi-level in-core file extent functionality, building upon the new layout introduced in mod xfs-linux:xfs-kern:207390a. The new multi-level extent allocations are only required for heavily fragmented files, so the old-style linear extent list is used on files until the extents reach a pre-determined size of 4k. 4k buffers are used because this is the system page size on Linux i386 and systems with larger page sizes don't seem to gain much, if anything, by using their native page size as the extent buffer size. Also, using 4k extent buffers everywhere provides a consistent interface for CXFS across different platforms. The 4k extent buffers are managed by an indirection array (xfs_ext_irec_t) which is basically just a pointer array with a bit of extra information to keep track of the number of extents in each buffer as well as the extent offset of each buffer. Major changes include: - Add multi-level in-core file extent functionality to the xfs_iext_ subroutines introduced in mod: xfs-linux:xfs-kern:207390a - Introduce 13 new subroutines which add functionality for multi-level in-core file extents: xfs_iext_add_indirect_multi() xfs_iext_remove_indirect() xfs_iext_realloc_indirect() xfs_iext_indirect_to_direct() xfs_iext_bno_to_irec() xfs_iext_idx_to_irec() xfs_iext_irec_init() xfs_iext_irec_new() xfs_iext_irec_remove() xfs_iext_irec_compact() xfs_iext_irec_compact_pages() xfs_iext_irec_compact_full() xfs_iext_irec_update_extoffs() SGI-PV: 928864 SGI-Modid: xfs-linux-melb:xfs-kern:207393a Signed-off-by: Mandy Kirkconnell Signed-off-by: Nathan Scott --- fs/xfs/xfs_bmap.c | 59 +++++++++++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 51 insertions(+), 8 deletions(-) (limited to 'fs/xfs/xfs_bmap.c') diff --git a/fs/xfs/xfs_bmap.c b/fs/xfs/xfs_bmap.c index 53c47a181f87..81a95b684b6b 100644 --- a/fs/xfs/xfs_bmap.c +++ b/fs/xfs/xfs_bmap.c @@ -3423,6 +3423,7 @@ xfs_bmap_local_to_extents( xfs_bmap_forkoff_reset(args.mp, ip, whichfork); xfs_idata_realloc(ip, -ifp->if_bytes, whichfork); xfs_iext_add(ifp, 0, 1); + ASSERT((ifp->if_flags & (XFS_IFEXTENTS|XFS_IFEXTIREC)) == XFS_IFEXTENTS); ep = xfs_iext_get_ext(ifp, 0); xfs_bmbt_set_allf(ep, 0, args.fsbno, 1, XFS_EXT_NORM); xfs_bmap_trace_post_update(fname, "new", ip, 0, whichfork); @@ -3551,6 +3552,54 @@ xfs_bmap_do_search_extents( return ep; } +/* + * Call xfs_bmap_do_search_extents() to search for the extent + * record containing block bno. If in multi-level in-core extent + * allocation mode, find and extract the target extent buffer, + * otherwise just use the direct extent list. + */ +xfs_bmbt_rec_t * /* pointer to found extent entry */ +xfs_bmap_search_multi_extents( + xfs_ifork_t *ifp, /* inode fork pointer */ + xfs_fileoff_t bno, /* block number searched for */ + int *eofp, /* out: end of file found */ + xfs_extnum_t *lastxp, /* out: last extent index */ + xfs_bmbt_irec_t *gotp, /* out: extent entry found */ + xfs_bmbt_irec_t *prevp) /* out: previous extent entry found */ +{ + xfs_bmbt_rec_t *base; /* base of extent records */ + xfs_bmbt_rec_t *ep; /* extent record pointer */ + xfs_ext_irec_t *erp = NULL; /* indirection array pointer */ + xfs_extnum_t lastx; /* last extent index */ + xfs_extnum_t nextents; /* number of file extents */ + + /* + * For multi-level extent allocation mode, find the + * target extent list and pass only the contiguous + * list to xfs_bmap_do_search_extents. Convert lastx + * from a file extent index to an index within the + * target extent list. + */ + if (ifp->if_flags & XFS_IFEXTIREC) { + int erp_idx = 0; + erp = xfs_iext_bno_to_irec(ifp, bno, &erp_idx); + base = erp->er_extbuf; + nextents = erp->er_extcount; + lastx = ifp->if_lastex - erp->er_extoff; + } else { + base = &ifp->if_u1.if_extents[0]; + nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t); + lastx = ifp->if_lastex; + } + ep = xfs_bmap_do_search_extents(base, lastx, nextents, bno, + eofp, lastxp, gotp, prevp); + /* Convert lastx back to file-based index */ + if (ifp->if_flags & XFS_IFEXTIREC) { + *lastxp += erp->er_extoff; + } + return ep; +} + /* * Search the extents list for the inode, for the extent containing bno. * If bno lies in a hole, point to the next entry. If bno lies past eof, @@ -3569,20 +3618,14 @@ xfs_bmap_search_extents( xfs_bmbt_irec_t *prevp) /* out: previous extent entry found */ { xfs_ifork_t *ifp; /* inode fork pointer */ - xfs_bmbt_rec_t *base; /* base of extent list */ - xfs_extnum_t lastx; /* last extent index used */ - xfs_extnum_t nextents; /* number of file extents */ xfs_bmbt_rec_t *ep; /* extent record pointer */ int rt; /* realtime flag */ XFS_STATS_INC(xs_look_exlist); ifp = XFS_IFORK_PTR(ip, whichfork); - lastx = ifp->if_lastex; - nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t); - base = &ifp->if_u1.if_extents[0]; - ep = xfs_bmap_do_search_extents(base, lastx, nextents, bno, eofp, - lastxp, gotp, prevp); + ep = xfs_bmap_search_multi_extents(ifp, bno, eofp, lastxp, gotp, prevp); + rt = (whichfork == XFS_DATA_FORK) && XFS_IS_REALTIME_INODE(ip); if (unlikely(!rt && !gotp->br_startblock && (*lastxp != NULLEXTNUM))) { cmn_err(CE_PANIC,"Access to block zero: fs: <%s> inode: %lld " -- cgit v1.2.3