From patchwork Tue Nov 21 15:16:55 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nikolay Borisov X-Patchwork-Id: 10068453 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 9910B6022E for ; Tue, 21 Nov 2017 15:20:25 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8955529757 for ; Tue, 21 Nov 2017 15:20:25 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 7D5F629759; Tue, 21 Nov 2017 15:20:25 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D80522975C for ; Tue, 21 Nov 2017 15:20:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751314AbdKUPRJ (ORCPT ); Tue, 21 Nov 2017 10:17:09 -0500 Received: from mx2.suse.de ([195.135.220.15]:56666 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751310AbdKUPRG (ORCPT ); Tue, 21 Nov 2017 10:17:06 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 0611EAD31; Tue, 21 Nov 2017 15:17:05 +0000 (UTC) From: Nikolay Borisov To: linux-xfs@vger.kernel.org Cc: fstests@vger.kernel.org, eguan@redhat.com, sandeen@sandeen.net, Nikolay Borisov , Eric Sandeen Subject: [PATCH v5] xfs_io: implement ranged fiemap query Date: Tue, 21 Nov 2017 17:16:55 +0200 Message-Id: <1511277416-3191-1-git-send-email-nborisov@suse.com> X-Mailer: git-send-email 2.7.4 Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Currently the fiemap implementation of xfs_io doesn't support making ranged queries. This patch implements two optional arguments which take the starting offset and the length of the region to be queried. When the end of the requested region falls within an extend boundary then we print the whole extent (i.e. return the information that the kernel has given us). When the end offset falls within a hole then the printed range is truncated to the requested one since we do not have information how long the hole is Signed-off-by: Nikolay Borisov [sandeen: simplify/rewrite ranged logic] Signed-off-by: Eric Sandeen --- V5: * Now based on Eric's simpler approach. V4: * Don't do any fiemap processing if passed offset is past EOF. Filesystems might have custom handling for this. XFS for example pretends there is a hole. * Restore offset/len handling to using the optional params at the end of getopt and not using an additional '-r' param V3: * Fixed a bug where incorrect extent index was shown if we didn't print a hole. This was due to statically returning 2 at the end of print_(plain|verbose) Now, the actual number of printed extents inside the 2 functions is used. This bug is visible only with the -r parameter * Fixed a bug where 1 additional extent would be printed. This was a result of the aforementioned bug fix, since now printing function can return 1 and still have printed an extent and no hole. This can happen when you use -r parameter, this is now fixed and a comment explaining it is put. * Reworked the handling of the new params by making them arguments to the -r parameter. V2: * Incorporated Daricks feedback - removed variables which weren't introduced until the next patch as a result the build with this patch was broken. This is fixed now io/fiemap.c | 67 +++++++++++++++++++++++++++++++++++++++++++++---------- man/man8/xfs_io.8 | 5 +++-- 2 files changed, 58 insertions(+), 14 deletions(-) diff --git a/io/fiemap.c b/io/fiemap.c index bdcfacdb2811..b94d6429566c 100644 --- a/io/fiemap.c +++ b/io/fiemap.c @@ -49,6 +49,8 @@ fiemap_help(void) " -l -- also displays the length of each extent in 512-byte blocks.\n" " -n -- query n extents.\n" " -v -- Verbose information\n" +" offset is the starting offset to map, and is optional. If offset is\n" +" specified, mapping length may (optionally) be specified as well." "\n")); } @@ -101,6 +103,7 @@ print_verbose( char lbuf[48]; char bbuf[48]; char flgbuf[16]; + int num_printed = 0; llast = BTOBBT(last_logical); lstart = BTOBBT(extent->fe_logical); @@ -118,14 +121,15 @@ print_verbose( flg_w, _("FLAGS")); } - if (lstart != llast) { + if (lstart > llast) { print_hole(foff_w, boff_w, tot_w, cur_extent, 0, false, llast, lstart); cur_extent++; + num_printed++; } if (cur_extent == max_extents) - return 1; + return num_printed; snprintf(lbuf, sizeof(lbuf), "[%llu..%llu]:", (unsigned long long)lstart, lstart + len - 1ULL); @@ -135,7 +139,9 @@ print_verbose( printf("%4d: %-*s %-*s %*llu %*s\n", cur_extent, foff_w, lbuf, boff_w, bbuf, tot_w, (unsigned long long)len, flg_w, flgbuf); - return 2; + num_printed++; + + return num_printed; } static int @@ -149,29 +155,33 @@ print_plain( __u64 llast; __u64 block; __u64 len; + int num_printed = 0; llast = BTOBBT(last_logical); lstart = BTOBBT(extent->fe_logical); len = BTOBBT(extent->fe_length); block = BTOBBT(extent->fe_physical); - if (lstart != llast) { + if (lstart > llast) { print_hole(0, 0, 0, cur_extent, lflag, true, llast, lstart); cur_extent++; + num_printed++; } if (cur_extent == max_extents) - return 1; + return num_printed; printf("\t%d: [%llu..%llu]: %llu..%llu", cur_extent, (unsigned long long)lstart, lstart + len - 1ULL, (unsigned long long)block, block + len - 1ULL); + num_printed++; + if (lflag) printf(_(" %llu blocks\n"), (unsigned long long)len); else printf("\n"); - return 2; + return num_printed; } /* @@ -235,9 +245,15 @@ fiemap_f( int boff_w = 16; int tot_w = 5; /* 5 since its just one number */ int flg_w = 5; - __u64 last_logical = 0; + __u64 last_logical = 0; /* last extent offset handled */ + off64_t start_offset = 0; /* mapping start */ + off64_t length = -1LL; /* mapping length */ + off64_t range_end = -1LL; /* mapping end*/ + size_t fsblocksize, fssectsize; struct stat st; + init_cvtnum(&fsblocksize, &fssectsize); + while ((c = getopt(argc, argv, "aln:v")) != EOF) { switch (c) { case 'a': @@ -257,6 +273,27 @@ fiemap_f( } } + /* Range start (optional) */ + if (optind < argc) { + start_offset = cvtnum(fsblocksize, fssectsize, argv[optind]); + if (start_offset < 0) { + printf("non-numeric offset argument -- %s\n", argv[optind]); + return 0; + } + last_logical = start_offset; + optind++; + } + + /* Range length (optional if range start was specified) */ + if (optind < argc) { + length = cvtnum(fsblocksize, fssectsize, argv[optind]); + if (length < 0) { + printf("non-numeric len argument -- %s\n", argv[optind]); + return 0; + } + range_end = start_offset + length; + } + map_size = sizeof(struct fiemap) + (EXTENT_BATCH * sizeof(struct fiemap_extent)); fiemap = malloc(map_size); @@ -269,12 +306,15 @@ fiemap_f( printf("%s:\n", file->name); - while (!last && (cur_extent != max_extents)) { + while (!last /* last extent of file */ + && (cur_extent != max_extents) /* limit passed to -n */ + && last_logical < range_end /* printed requested range */ + ) { memset(fiemap, 0, map_size); fiemap->fm_flags = fiemap_flags; fiemap->fm_start = last_logical; - fiemap->fm_length = -1LL; + fiemap->fm_length = range_end - last_logical; fiemap->fm_extent_count = EXTENT_BATCH; ret = ioctl(file->fd, FS_IOC_FIEMAP, (unsigned long)fiemap); @@ -336,9 +376,12 @@ fiemap_f( return 0; } - if (cur_extent && last_logical < st.st_size) + /* Print last hole to EOF or to end of requested range */ + range_end = min((uint64_t)range_end, st.st_size); + + if (cur_extent && last_logical < range_end) print_hole(foff_w, boff_w, tot_w, cur_extent, lflag, !vflag, - BTOBBT(last_logical), BTOBBT(st.st_size)); + BTOBBT(last_logical), BTOBBT(range_end)); out: free(fiemap); @@ -353,7 +396,7 @@ fiemap_init(void) fiemap_cmd.argmin = 0; fiemap_cmd.argmax = -1; fiemap_cmd.flags = CMD_NOMAP_OK | CMD_FOREIGN_OK; - fiemap_cmd.args = _("[-alv] [-n nx]"); + fiemap_cmd.args = _("[-alv] [-n nx] [offset [len]]"); fiemap_cmd.oneline = _("print block mapping for a file"); fiemap_cmd.help = fiemap_help; diff --git a/man/man8/xfs_io.8 b/man/man8/xfs_io.8 index 9bf1a4783c4f..76337346ca0c 100644 --- a/man/man8/xfs_io.8 +++ b/man/man8/xfs_io.8 @@ -304,11 +304,12 @@ Prints the block mapping for the current open file. Refer to the .BR xfs_bmap (8) manual page for complete documentation. .TP -.BI "fiemap [ \-alv ] [ \-n " nx " ]" +.BI "fiemap [ \-alv ] [ \-n " nx " ] [ " offset " [ " len " ]]" Prints the block mapping for the current open file using the fiemap ioctl. Options behave as described in the .BR xfs_bmap (8) -manual page. +manual page. Optionally, this command also supports passing the start offset +from where to begin the fiemap and the length of that region. .TP .BI "fsmap [ \-d | \-l | \-r ] [ \-m | \-v ] [ \-n " nx " ] [ " start " ] [ " end " ] Prints the mapping of disk blocks used by the filesystem hosting the current