From 39269e29d4aad04252e0debec4c9b01bac16a257 Mon Sep 17 00:00:00 2001 From: Nathan Scott Date: Tue, 14 Mar 2006 13:33:50 +1100 Subject: [PATCH] [XFS] Reduce xfs_bmapi stack use by removing some local state variables, and directly testing flags instead. SGI-PV: 947312 SGI-Modid: xfs-linux-melb:xfs-kern:25370a Signed-off-by: Nathan Scott --- fs/xfs/xfs_bmap.c | 79 ++++++++++++++++++++++------------------------- 1 file changed, 37 insertions(+), 42 deletions(-) diff --git a/fs/xfs/xfs_bmap.c b/fs/xfs/xfs_bmap.c index 81a95b684b6b..da8fa0cd79c1 100644 --- a/fs/xfs/xfs_bmap.c +++ b/fs/xfs/xfs_bmap.c @@ -4629,10 +4629,6 @@ xfs_bmapi( xfs_btree_cur_t *cur; /* bmap btree cursor */ xfs_fileoff_t end; /* end of mapped file region */ int eof; /* we've hit the end of extents */ - char contig; /* allocation must be one extent */ - char delay; /* this request is for delayed alloc */ - char exact; /* don't do all of wasdelayed extent */ - char convert; /* unwritten extent I/O completion */ xfs_bmbt_rec_t *ep; /* extent record pointer */ int error; /* error return */ xfs_bmbt_irec_t got; /* current file extent record */ @@ -4651,13 +4647,9 @@ xfs_bmapi( int tmp_logflags; /* temp flags holder */ int whichfork; /* data or attr fork */ char inhole; /* current location is hole in file */ - char stateless; /* ignore state flag set */ - char trim; /* output trimmed to match range */ - char userdata; /* allocating non-metadata */ char wasdelay; /* old extent was delayed */ char wr; /* this is a write request */ char rt; /* this is a realtime file */ - char rsvd; /* OK to allocate reserved blocks */ #ifdef DEBUG xfs_fileoff_t orig_bno; /* original block number value */ int orig_flags; /* original flags arg value */ @@ -4694,15 +4686,8 @@ xfs_bmapi( XFS_STATS_INC(xs_blk_mapw); else XFS_STATS_INC(xs_blk_mapr); - delay = (flags & XFS_BMAPI_DELAY) != 0; - trim = (flags & XFS_BMAPI_ENTIRE) == 0; - userdata = (flags & XFS_BMAPI_METADATA) == 0; - convert = (flags & XFS_BMAPI_CONVERT) != 0; - exact = (flags & XFS_BMAPI_EXACT) != 0; - rsvd = (flags & XFS_BMAPI_RSVBLOCKS) != 0; - contig = (flags & XFS_BMAPI_CONTIG) != 0; /* - * stateless is used to combine extents which + * IGSTATE flag is used to combine extents which * differ only due to the state of the extents. * This technique is used from xfs_getbmap() * when the caller does not wish to see the @@ -4718,10 +4703,9 @@ xfs_bmapi( * xfs_strat_comp(), where the xfs_bmapi() call * is transactioned, and the extents combined. */ - stateless = (flags & XFS_BMAPI_IGSTATE) != 0; - if (stateless && wr) /* if writing unwritten space, no */ - wr = 0; /* allocations are allowed */ - ASSERT(wr || !delay); + if ((flags & XFS_BMAPI_IGSTATE) && wr) /* if writing unwritten space */ + wr = 0; /* no allocations are allowed */ + ASSERT(wr || !(flags & XFS_BMAPI_DELAY)); logflags = 0; nallocs = 0; cur = NULL; @@ -4756,7 +4740,7 @@ xfs_bmapi( if (eof && !wr) got.br_startoff = end; inhole = eof || got.br_startoff > bno; - wasdelay = wr && !inhole && !delay && + wasdelay = wr && !inhole && !(flags & XFS_BMAPI_DELAY) && ISNULLSTARTBLOCK(got.br_startblock); /* * First, deal with the hole before the allocated space @@ -4768,7 +4752,7 @@ xfs_bmapi( * allocate the stuff asked for in this bmap call * but that wouldn't be as good. */ - if (wasdelay && !exact) { + if (wasdelay && !(flags & XFS_BMAPI_EXACT)) { alen = (xfs_extlen_t)got.br_blockcount; aoff = got.br_startoff; if (lastx != NULLEXTNUM && lastx) { @@ -4790,8 +4774,8 @@ xfs_bmapi( got.br_startoff - bno); aoff = bno; } - minlen = contig ? alen : 1; - if (delay) { + minlen = (flags & XFS_BMAPI_CONTIG) ? alen : 1; + if (flags & XFS_BMAPI_DELAY) { xfs_extlen_t extsz; /* Figure out the extent size, adjust alen */ @@ -4804,7 +4788,9 @@ xfs_bmapi( if (extsz) { error = xfs_bmap_extsize_align(mp, &got, &prev, extsz, - rt, eof, delay, convert, + rt, eof, + flags&XFS_BMAPI_DELAY, + flags&XFS_BMAPI_CONVERT, &aoff, &alen); ASSERT(!error); } @@ -4842,24 +4828,29 @@ xfs_bmapi( if (rt) { error = xfs_mod_incore_sb(mp, XFS_SBS_FREXTENTS, - -(extsz), rsvd); + -(extsz), (flags & + XFS_BMAPI_RSVBLOCKS)); } else { error = xfs_mod_incore_sb(mp, XFS_SBS_FDBLOCKS, - -(alen), rsvd); + -(alen), (flags & + XFS_BMAPI_RSVBLOCKS)); } if (!error) { error = xfs_mod_incore_sb(mp, XFS_SBS_FDBLOCKS, - -(indlen), rsvd); + -(indlen), (flags & + XFS_BMAPI_RSVBLOCKS)); if (error && rt) xfs_mod_incore_sb(mp, XFS_SBS_FREXTENTS, - extsz, rsvd); + extsz, (flags & + XFS_BMAPI_RSVBLOCKS)); else if (error) xfs_mod_incore_sb(mp, XFS_SBS_FDBLOCKS, - alen, rsvd); + alen, (flags & + XFS_BMAPI_RSVBLOCKS)); } if (error) { @@ -4892,7 +4883,7 @@ xfs_bmapi( /* Indicate if this is the first user data * in the file, or just any user data. */ - if (userdata) { + if (!(flags & XFS_BMAPI_METADATA)) { bma.userdata = (aoff == 0) ? XFS_ALLOC_INITIAL_USER_DATA : XFS_ALLOC_USERDATA; @@ -4904,7 +4895,7 @@ xfs_bmapi( bma.firstblock = *firstblock; bma.alen = alen; bma.off = aoff; - bma.conv = convert; + bma.conv = (flags & XFS_BMAPI_CONVERT); bma.wasdel = wasdelay; bma.minlen = minlen; bma.low = flist->xbf_low; @@ -4915,7 +4906,8 @@ xfs_bmapi( * is larger than a stripe unit. */ if (mp->m_dalign && alen >= mp->m_dalign && - userdata && whichfork == XFS_DATA_FORK) { + (!(flags & XFS_BMAPI_METADATA)) && + (whichfork == XFS_DATA_FORK)) { if ((error = xfs_bmap_isaeof(ip, aoff, whichfork, &bma.aeof))) goto error0; @@ -4978,7 +4970,7 @@ xfs_bmapi( } error = xfs_bmap_add_extent(ip, lastx, &cur, &got, firstblock, flist, &tmp_logflags, whichfork, - rsvd); + (flags & XFS_BMAPI_RSVBLOCKS)); logflags |= tmp_logflags; if (error) goto error0; @@ -4990,7 +4982,7 @@ xfs_bmapi( ASSERT(got.br_startoff + got.br_blockcount >= aoff + alen); #ifdef DEBUG - if (delay) { + if (flags & XFS_BMAPI_DELAY) { ASSERT(ISNULLSTARTBLOCK(got.br_startblock)); ASSERT(STARTBLOCKVAL(got.br_startblock) > 0); } @@ -5019,14 +5011,15 @@ xfs_bmapi( * Then deal with the allocated space we found. */ ASSERT(ep != NULL); - if (trim && (got.br_startoff + got.br_blockcount > obno)) { + if (!(flags & XFS_BMAPI_ENTIRE) && + (got.br_startoff + got.br_blockcount > obno)) { if (obno > bno) bno = obno; ASSERT((bno >= obno) || (n == 0)); ASSERT(bno < end); mval->br_startoff = bno; if (ISNULLSTARTBLOCK(got.br_startblock)) { - ASSERT(!wr || delay); + ASSERT(!wr || (flags & XFS_BMAPI_DELAY)); mval->br_startblock = DELAYSTARTBLOCK; } else mval->br_startblock = @@ -5048,7 +5041,7 @@ xfs_bmapi( } else { *mval = got; if (ISNULLSTARTBLOCK(mval->br_startblock)) { - ASSERT(!wr || delay); + ASSERT(!wr || (flags & XFS_BMAPI_DELAY)); mval->br_startblock = DELAYSTARTBLOCK; } } @@ -5074,7 +5067,7 @@ xfs_bmapi( mval->br_state = XFS_EXT_NORM; error = xfs_bmap_add_extent(ip, lastx, &cur, mval, firstblock, flist, &tmp_logflags, whichfork, - rsvd); + (flags & XFS_BMAPI_RSVBLOCKS)); logflags |= tmp_logflags; if (error) goto error0; @@ -5091,9 +5084,10 @@ xfs_bmapi( continue; } - ASSERT(!trim || + ASSERT((flags & XFS_BMAPI_ENTIRE) || ((mval->br_startoff + mval->br_blockcount) <= end)); - ASSERT(!trim || (mval->br_blockcount <= len) || + ASSERT((flags & XFS_BMAPI_ENTIRE) || + (mval->br_blockcount <= len) || (mval->br_startoff < obno)); bno = mval->br_startoff + mval->br_blockcount; len = end - bno; @@ -5108,7 +5102,8 @@ xfs_bmapi( mval[-1].br_startblock != HOLESTARTBLOCK && mval->br_startblock == mval[-1].br_startblock + mval[-1].br_blockcount && - (stateless || mval[-1].br_state == mval->br_state)) { + ((flags & XFS_BMAPI_IGSTATE) || + mval[-1].br_state == mval->br_state)) { ASSERT(mval->br_startoff == mval[-1].br_startoff + mval[-1].br_blockcount); mval[-1].br_blockcount += mval->br_blockcount;