Weekly Edition
Return to the Kernel page
| ||||||||||||||||
NTFS: 2.0.19 Fix race condition, improvements, and optimizations in i/o interface
Linus, please do a bk pull http://linux-ntfs.bkbits.net/ntfs-tng-2.5 Thanks! - This completes the work on the ntfs (read) address space operations. Now hopefully race free, bug free, and uptodate with current kernel core. Best regards, Anton -- Anton Altaparmakov <aia21 at cantab.net> (replace at with @) Linux NTFS maintainer / IRC: #ntfs on irc.openprojects.net WWW: http://linux-ntfs.sf.net/, http://www-stu.christs.cam.ac.uk/~aia21/ =================================================================== This will update the following files: Documentation/filesystems/ntfs.txt | 3 + fs/ntfs/ChangeLog | 20 +++++++--- fs/ntfs/Makefile | 2 - fs/ntfs/aops.c | 71 +++++++++++++++++++++---------------- fs/ntfs/compress.c | 40 +++++++++++++++----- fs/ntfs/inode.c | 22 ++++------- fs/ntfs/ntfs.h | 2 - 7 files changed, 101 insertions(+), 59 deletions(-) through these ChangeSets: <aia21@cantab.net> (02/07/13 1.622) NTFS: 2.0.19 - Fix race condition, improvements, and optimizations in i/o interface. - Apply block optimization added to fs/ntfs/aops.c::ntfs_read_block() to fs/ntfs/compress.c::ntfs_file_read_compressed_block() as well. - Drop the "file" from ntfs_file_read_compressed_block(). - Rename fs/ntfs/aops.c::ntfs_enb_buffer_read_async() to ntfs_end_buffer_async_read() (more like the fs/buffer.c counterpart). - Update ntfs_end_buffer_async_read() with the improved logic from its updated counterpart fs/buffer.c::end_buffer_async_read(). Apply further logic improvements to better determine when we set PageError. - Update submission of buffers in fs/ntfs/aops.c::ntfs_read_block() to check for the buffers being uptodate first in line with the updated fs/buffer.c::block_read_full_page(). This plugs a small race condition. diff -Nru a/Documentation/filesystems/ntfs.txt b/Documentation/filesystems/ntfs.txt --- a/Documentation/filesystems/ntfs.txt Sat Jul 13 01:30:36 2002 +++ b/Documentation/filesystems/ntfs.txt Sat Jul 13 01:30:36 2002 @@ -247,6 +247,9 @@ Note, a technical ChangeLog aimed at kernel hackers is in fs/ntfs/ChangeLog. +2.0.19: + - Fix race condition and improvements in block i/o interface. + - Optimization when reading compressed files. 2.0.18: - Fix race condition in reading of compressed files. 2.0.17: diff -Nru a/fs/ntfs/ChangeLog b/fs/ntfs/ChangeLog --- a/fs/ntfs/ChangeLog Sat Jul 13 01:30:36 2002 +++ b/fs/ntfs/ChangeLog Sat Jul 13 01:30:36 2002 @@ -9,12 +9,22 @@ read() will fail when s_maxbytes is reached? -> Investigate this. - Implement/allow non-resident index bitmaps in dir.c::ntfs_readdir() and then also consider initialized_size w.r.t. the bitmaps, etc. - - Consider if ntfs_file_read_compressed_block() shouldn't be coping - with initialized_size < data_size. I don't think it can happen but - it requires more careful consideration. - Enable NFS exporting of NTFS. - - Apply block resolution optimization from aops.c::ntfs_read_block() to - compress.c::ntfs_file_read_compressed_block() as well. + +2.0.19 - Fix race condition, improvements, and optimizations in i/o interface. + + - Apply block optimization added to fs/ntfs/aops.c::ntfs_read_block() + to fs/ntfs/compress.c::ntfs_file_read_compressed_block() as well. + - Drop the "file" from ntfs_file_read_compressed_block(). + - Rename fs/ntfs/aops.c::ntfs_enb_buffer_read_async() to + ntfs_end_buffer_async_read() (more like the fs/buffer.c counterpart). + - Update ntfs_end_buffer_async_read() with the improved logic from + its updated counterpart fs/buffer.c::end_buffer_async_read(). Apply + further logic improvements to better determine when we set PageError. + - Update submission of buffers in fs/ntfs/aops.c::ntfs_read_block() to + check for the buffers being uptodate first in line with the updated + fs/buffer.c::block_read_full_page(). This plugs a small race + condition. 2.0.18 - Fix race condition in reading of compressed files. diff -Nru a/fs/ntfs/Makefile b/fs/ntfs/Makefile --- a/fs/ntfs/Makefile Sat Jul 13 01:30:36 2002 +++ b/fs/ntfs/Makefile Sat Jul 13 01:30:36 2002 @@ -5,7 +5,7 @@ ntfs-objs := aops.o attrib.o compress.o debug.o dir.o file.o inode.o mft.o \ mst.o namei.o super.o sysctl.o time.o unistr.o upcase.o -EXTRA_CFLAGS = -DNTFS_VERSION=\"2.0.18\" +EXTRA_CFLAGS = -DNTFS_VERSION=\"2.0.19\" ifeq ($(CONFIG_NTFS_DEBUG),y) EXTRA_CFLAGS += -DDEBUG diff -Nru a/fs/ntfs/aops.c b/fs/ntfs/aops.c --- a/fs/ntfs/aops.c Sat Jul 13 01:30:36 2002 +++ b/fs/ntfs/aops.c Sat Jul 13 01:30:36 2002 @@ -30,7 +30,7 @@ #include "ntfs.h" /** - * ntfs_end_buffer_read_async - async io completion for reading attributes + * ntfs_end_buffer_async_read - async io completion for reading attributes * @bh: buffer head on which io is completed * @uptodate: whether @bh is now uptodate or not * @@ -45,26 +45,23 @@ * record size, and index_block_size_bits, to the log(base 2) of the ntfs * record size. */ -static void ntfs_end_buffer_read_async(struct buffer_head *bh, int uptodate) +static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate) { static spinlock_t page_uptodate_lock = SPIN_LOCK_UNLOCKED; unsigned long flags; struct buffer_head *tmp; struct page *page; ntfs_inode *ni; - - if (likely(uptodate)) - set_buffer_uptodate(bh); - else - clear_buffer_uptodate(bh); + int page_uptodate = 1; page = bh->b_page; - ni = NTFS_I(page->mapping->host); if (likely(uptodate)) { s64 file_ofs; + set_buffer_uptodate(bh); + file_ofs = (page->index << PAGE_CACHE_SHIFT) + bh_offset(bh); /* Check for the current buffer head overflowing. */ if (file_ofs + bh->b_size > ni->initialized_size) { @@ -78,22 +75,28 @@ flush_dcache_page(page); kunmap_atomic(addr, KM_BIO_SRC_IRQ); } - } else + } else { + clear_buffer_uptodate(bh); + ntfs_error(ni->vol->sb, "Buffer I/O error, logical block %Lu.", + (unsigned long long)bh->b_blocknr); SetPageError(page); + } spin_lock_irqsave(&page_uptodate_lock, flags); clear_buffer_async_read(bh); unlock_buffer(bh); - - tmp = bh->b_this_page; - while (tmp != bh) { - if (buffer_locked(tmp)) { - if (buffer_async_read(tmp)) + tmp = bh; + do { + if (!buffer_uptodate(tmp)) + page_uptodate = 0; + if (buffer_async_read(tmp)) { + if (likely(buffer_locked(tmp))) goto still_busy; - } else if (!buffer_uptodate(tmp)) - SetPageError(page); + /* Async buffers must be locked. */ + BUG(); + } tmp = tmp->b_this_page; - } + } while (tmp != bh); spin_unlock_irqrestore(&page_uptodate_lock, flags); /* * If none of the buffers had errors then we can set the page uptodate, @@ -101,7 +104,7 @@ * attribute is mst protected, i.e. if NInoMstProteced(ni) is true. */ if (!NInoMstProtected(ni)) { - if (likely(!PageError(page))) + if (likely(page_uptodate && !PageError(page))) SetPageUptodate(page); unlock_page(page); return; @@ -127,12 +130,15 @@ } flush_dcache_page(page); kunmap_atomic(addr, KM_BIO_SRC_IRQ); - if (likely(!nr_err && recs)) - SetPageUptodate(page); - else { - ntfs_error(ni->vol->sb, "Setting page error, index " - "0x%lx.", page->index); - SetPageError(page); + if (likely(!PageError(page))) { + if (likely(!nr_err && recs)) { + if (likely(page_uptodate)) + SetPageUptodate(page); + } else { + ntfs_error(ni->vol->sb, "Setting page error, " + "index 0x%lx.", page->index); + SetPageError(page); + } } } unlock_page(page); @@ -282,16 +288,23 @@ /* Check we have at least one buffer ready for i/o. */ if (nr) { + struct buffer_head *tbh; + /* Lock the buffers. */ for (i = 0; i < nr; i++) { - struct buffer_head *tbh = arr[i]; + tbh = arr[i]; lock_buffer(tbh); - tbh->b_end_io = ntfs_end_buffer_read_async; + tbh->b_end_io = ntfs_end_buffer_async_read; set_buffer_async_read(tbh); } /* Finally, start i/o on the buffers. */ - for (i = 0; i < nr; i++) - submit_bh(READ, arr[i]); + for (i = 0; i < nr; i++) { + tbh = arr[i]; + if (likely(!buffer_uptodate(tbh))) + submit_bh(READ, tbh); + else + ntfs_end_buffer_async_read(tbh, 1); + } return 0; } /* No i/o was scheduled on any of the buffers. */ @@ -349,7 +362,7 @@ } /* Compressed data streams are handled in compress.c. */ if (NInoCompressed(ni)) - return ntfs_file_read_compressed_block(page); + return ntfs_read_compressed_block(page); } /* Normal data stream. */ return ntfs_read_block(page); diff -Nru a/fs/ntfs/compress.c b/fs/ntfs/compress.c --- a/fs/ntfs/compress.c Sat Jul 13 01:30:36 2002 +++ b/fs/ntfs/compress.c Sat Jul 13 01:30:36 2002 @@ -386,7 +386,7 @@ } /** - * ntfs_file_read_compressed_block - read a compressed block into the page cache + * ntfs_read_compressed_block - read a compressed block into the page cache * @page: locked page in the compression block(s) we need to read * * When we are called the page has already been verified to be locked and the @@ -418,14 +418,15 @@ * initialized_size is less than data_size. This should be safe because of the * nature of the compression algorithm used. Just in case we check and output * an error message in read inode if the two sizes are not equal for a - * compressed file. + * compressed file. (AIA) */ -int ntfs_file_read_compressed_block(struct page *page) +int ntfs_read_compressed_block(struct page *page) { struct address_space *mapping = page->mapping; ntfs_inode *ni = NTFS_I(mapping->host); ntfs_volume *vol = ni->vol; struct super_block *sb = vol->sb; + run_list_element *rl; unsigned long block_size = sb->s_blocksize; unsigned char block_size_bits = sb->s_blocksize_bits; u8 *cb, *cb_pos, *cb_end; @@ -532,14 +533,23 @@ nr_bhs = 0; /* Read all cb buffer heads one cluster at a time. */ + rl = NULL; for (vcn = start_vcn, start_vcn += cb_clusters; vcn < start_vcn; vcn++) { BOOL is_retry = FALSE; -retry_remap: - /* Find lcn of vcn and convert it into blocks. */ - down_read(&ni->run_list.lock); - lcn = vcn_to_lcn(ni->run_list.rl, vcn); - up_read(&ni->run_list.lock); + + if (!rl) { +lock_retry_remap: + down_read(&ni->run_list.lock); + rl = ni->run_list.rl; + } + if (likely(rl != NULL)) { + /* Seek to element containing target vcn. */ + while (rl->length && rl[1].vcn <= vcn) + rl++; + lcn = vcn_to_lcn(rl, vcn); + } else + lcn = (LCN)LCN_RL_NOT_MAPPED; ntfs_debug("Reading vcn = 0x%Lx, lcn = 0x%Lx.", (long long)vcn, (long long)lcn); if (lcn < 0) { @@ -552,9 +562,13 @@ if (is_retry || lcn != LCN_RL_NOT_MAPPED) goto rl_err; is_retry = TRUE; - /* Map run list of current extent and retry. */ + /* + * Attempt to map run list, dropping lock for the + * duration. + */ + up_read(&ni->run_list.lock); if (!map_run_list(ni, vcn)) - goto retry_remap; + goto lock_retry_remap; goto map_rl_err; } block = lcn << vol->cluster_size_bits >> block_size_bits; @@ -568,6 +582,10 @@ } while (++block < max_block); } + /* Release the lock if we took it. */ + if (rl) + up_read(&ni->run_list.lock); + /* Setup and initiate io on all buffer heads. */ for (i = 0; i < nr_bhs; i++) { struct buffer_head *tbh = bhs[i]; @@ -828,11 +846,13 @@ goto err_out; rl_err: + up_read(&ni->run_list.lock); ntfs_error(vol->sb, "vcn_to_lcn() failed. Cannot read compression " "block."); goto err_out; getblk_err: + up_read(&ni->run_list.lock); ntfs_error(vol->sb, "getblk() failed. Cannot read compression block."); err_out: diff -Nru a/fs/ntfs/inode.c b/fs/ntfs/inode.c --- a/fs/ntfs/inode.c Sat Jul 13 01:30:36 2002 +++ b/fs/ntfs/inode.c Sat Jul 13 01:30:36 2002 @@ -1007,19 +1007,15 @@ ni->_ICF(compressed_size) = sle64_to_cpu( ctx->attr->_ANR(compressed_size)); if (vi->i_size != ni->initialized_size) - ntfs_warning(vi->i_sb, "Compressed " - "file with data_size " - "unequal to " - "initialized size " - "found. This will " - "probably cause " - "problems when trying " - "to access the file. " - "Please notify " - "linux-ntfs-dev@" - "lists.sf.net that you" - "saw this message." - "Thanks!"); + ntfs_warning(vi->i_sb, "BUG: Found " + "compressed file with " + "data_size not equal to " + "initialized_size. This will " + "probably cause problems when " + "trying to access the file. " + "Please notify linux-ntfs-dev@" + "lists.sf.net that you saw " + "this message. Thanks!"); } } else { /* Resident attribute. */ /* diff -Nru a/fs/ntfs/ntfs.h b/fs/ntfs/ntfs.h --- a/fs/ntfs/ntfs.h Sat Jul 13 01:30:36 2002 +++ b/fs/ntfs/ntfs.h Sat Jul 13 01:30:36 2002 @@ -158,7 +158,7 @@ /* Declarations of functions and global variables. */ /* From fs/ntfs/compress.c */ -extern int ntfs_file_read_compressed_block(struct page *page); +extern int ntfs_read_compressed_block(struct page *page); /* From fs/ntfs/super.c */ #define default_upcase_len 0x10000 =================================================================== This BitKeeper patch contains the following changesets: + ## Wrapped with gzip_uu ## begin 664 bkpatch21421 M'XL(`*QT+ST``^U::W.;2!;]#+^B[:E)R0_)-$])&:?B1$[6-9[$Y<1;6S69 M4C706%00:*#Q8U;SW_?>;M`#27;L5;)?-HY!@MOWU>?>/@W^B5P5/.]K+&8F MU7\B_\@*T=<"E@KF=U(NX-)EEL&EH[+(CXH\.!+IM0Y7+Y@(1N2&YT5?HQUK M=D7<3WA?NSQ]?W5^<JGKQ\?D[8BEU_P3%^3X6!=9?L.2L'C-Q"C)TH[(65J, MN6"=(!M/9Z)3TS!,^'&H9QF..Z6N87O3@(:4,IORT##MKFOKTNO7<V^;"CQ* M:0]4V%-*7=/0!X1V7-,DAGED>$?4(@;M6T;?<`_@@V&0ICYRX)&VH;\AVW7[ MK1Z0#Y_??>H3LV-T:(^TR;OXCN0LX"3(TC`6<98>DG@\R;,;/N:I*`X)2T.2 M340\CO]B>+\@<4KBHPQ.@N<1C.V`VC8YF4R2>^(G6?!U29ZP,.0A1$*BXB@5 M<	I.@$_3Y^&>:<A4,YJK4'>LBB(,0XR7DQ%X[BA*L1]2T^&TQ806YYDBAO M!GDV(6+$R2Z.V251GHW)HSK4V$N>LC%?[RY/_:%?1A'/E0Y6W*<!&!>9=+Z2 M"6L9>5M*@DQKG.6<)/%7+CT#U4JJ$T#V2\SFA.6B<N)J$C+!'U9X&XN15%7- M6$B2[#H.9+#2G5@4I)2*PD43BZ;[_0W:.VI&I9ZHS,%,7JE?Q`=.E\\%*"8A MA^,X3CFY'?$4YH(4@.0+=LU/\SS+E\(J2G\<%P7"(XN(LBZ!]2A&ZDP'(PY` MB[)<)J#6X/,XO8:012;-1'%>"%2;2+?J=%4I4:$MID+:4.:B,DF&$W`>,_%Y M%!=DDI37!6&D&+,DD46C'*D+IZ/_2BB%$M0OYKU';S_QGZX;S-!?D3>_3NM< M_,:^<D3ME/8\PZ#P8QD]IS<UX(LWC7A`?0?LVJ%A^:N]9%5-U:(L`_08]M2B MID>7+>*A,UICS[2FW2CLVE;`W<B@3N3XFPU66N;FJ&494Z?K&`US:K+7F#-, MO,ALSZ0A=RT&!C>;J[0TS,%'L\KG(`M*!*UL2T>8BN*^$'Q<>2KNQ#H7Z-1S M#)=[1F1RUP]]:TW$WZ"YD72S:QO.<A;B-`OYVC10>^H'H15UW<#MAD;0\\S- M::C5-`PZ5H\V#"J0GF?7Z\)VIV'D1CU&(7H>65YD;S8Y5]2$EN68UK+1>4]? M9[4[=:E-H\#K,B_T;&:ZFZTN:&K.N>4ZCN0`CT\,DH,M8F.5&GP[-A1GH%/: M-5Q/<@8(OTD9[(V4P?I>E$&U2]EK%6_`3J<`_)&T\UOY'SK7Q3>D^QG]\,RT M>\32E>F^KJTC+9*E+*U+T/05%VE0%1C^<9&=R+4*.SXN''-&0*3S'0FB%9A7 MF'EF':U"9&,=U8APJ&LY$A&4&D^`!'5(V_EQF%#EWL#$2G#/@,"`FH"``76) MJ9]1CT`G^Z)OF<-^06AL@\1JV^"PVO,IK/9L!JMMB\!J6^"OVG;HJ[8M]JIM MB;QJV^&NVG])7;4EYKK8YFJ>V.AR3V*AFWM<DX76+0Y9:+51ID_I<*1-?V"# MDU1Y0X.K(WM.?^L2JI_AX?1?GR]/AF_?G9^\_T2.27N`^_7A/T\O/YU]_'#\ M95?Y\F5W:<84WAKS]112O7FZEDFU89I.UW*GM@N9D)/E]98FBUHP7QLGRS9) MV^Q]E^F:];Q'>MR##4GNY_Z_2W^\T3W4X%1W4P[]3W?GRSMSN0W<4+DJG.?4 MK65AX<HCV7\`!I!3^87$F229"9>L`A-4<T\F1![[I>"%/K!E/Y#'`LET0&ZR M.'P(9H7(RT!4F1Z.T.2^/SI$@C-+^)X^<!SBZ&=.#Q1K>`M3.)Q-R#&A+_6! M:Z)QUP.NI6D`CMI:+=;R1WLO@2X-NE1V+4IL7?N;\*3@Y-\P)$@XR]</TC05 M`B*ME<;M5S=9TGY5^(=D]XV4)V=''XF\?:A@S)**C?U\7G9V#T&#IK7*M(BO M4UE(D#@\[/FC]BM?H3#-P=)9%Z/0_@8O/0RY1XFK:V(\@2#]$7@29M+9."*M MG::O(+:WAZ::Z3%>5D-6)T".D2JE`/:/Y+Z60[=X)0.ST+.0Q_9LX+0@?K1/ M3B0VZC(9EU`6/O0@.:I#]H]0[,W5^Y9,(<34<S'S\@B9OQWA:HW:R0Y&!U(# M:M@HHDY++BW'].(%V9D5O[PG/82M-.3KC%H.Z2T/7Y5>"7HGS7&*47?.@Z*6 MV.B$RK6F0<='Y5?U-$C]&/$BNAZ`$(P76$DXK@;1KE*M[<9IR.^(<?=S<@<X MDC+M5_*B,E%;7PA-F8;]9]=6M;"FQ@2""6K!!)A1%/5DOC6X#GAA>?Y[_,=+ MO-U3MWNSVXA7K&7H",</5#8.5G@Q`3`>#,:FT8HE&DE,?B%I#N>#@RK+RX8; M$[,"=`!+E7W9ZZ'61ZW+TY/!(1%5P6J8^86\K^T^`EL-K=$)NT#9%>4)1^9< ME'E*YJO%RK:ERO<BJ9EOG!K$YJE/D#:3F]4G2#4;M2W+5AMN:,+?3G"@:MKT M^SR$V>H+EA_T,@4(,SZ(V[#JSK/_K)57590ZU6OO6D\@`+D$L\7'.]6SH122 M@8')EA$PH"ZP^)IR75,GT-QX*-0AK9.SDSV4LY0<GG`Q?0#?5>N09O8EV'$@ MKN]:7J;#)"[$D">2K)']/('UR[%DY\X3J.8/5^?GT`<<JRM7;Z#1U,+G%6KU MRA,L_8H;B?P>CF,VZ6/EA=EMJBKT!;;*VE0'A55U2_U+]]`ZEO%2YP"Q'>5' MW<UAU?K$^5=$4^TX\"W!XA1;L&#Y-13$39#6RU>U2.70K!.>7@/7P^4A^9W^ MT0$I\LLQ"JM6E"<'!]*Y!&[(ZT.1#>$+C#Z48M)#4G<F)=8Z?_MA#WZ'E^?# M#Q\_#W\[N;@X'6#:@/3`/#F2^TC/\0@3>P*$>#P1&`(DC$`&"&;@D(2`]TDL MJ<5\GUX-"LN<*4XIO\O8RLD#20;[GK)?+0W:=086F_.%4^X92*4@LY>04E:H M#8@":H1,7609?!0JI3@[,/7Z(^:_`!6"M@26'Q0#(>=1H<7V7+UF:/3F)[W# MV-R8&^\PX$!=R\-W&-4S@MY3GA'TH"E;WZ4I5WLL<LMR"?LQU#P4-W8^];YE M0^NKXGO6DU!(*I;_&6[&)3FKE^;*B=8-S%P\5*3ZZGV?O(,M93@G0HUVIO9= ML[M`"]BPB/^"/6TF"/^S!`(.:%V@4;"C8@D(A%*LVGW=QK#IF@E!4GSFPV(5 ML!)0C%^A111JQSF3`NC+5I$1%@3@D-INRPX[D[E0=0"^Q-$][A/+NS8&VP[Y MS>N9%&*TZ!21G&XQ8H+<9R4IV.V",?2RGA[PF:5?BYW=!J;5"\L&I)_R+G0S MHI?>A1I=P!?^=8C3,ZKG*+;U!)KQW1YZ/7^A5V]U-\!=!?\LM+MR+58G?B<X @T,@G+[4OYW\W))]-%.7XN!N:78,[5/\/D!Y`?HDD```` ` end - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ |
||||||||||||||||