xfs_io: bmap should support querying CoW fork, shared blocks

Teach the bmap command to report shared and delayed allocation
extents, and to be able to query the CoW fork.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

diff --git a/io/bmap.c b/io/bmap.c
index b2e48da2512c0242c6949bee42225ff3b36abf3d..233324441fe2ab1353469ac80be1e3a8423f09af 100644 (file)
--- a/io/bmap.c
+++ b/io/bmap.c
@@ -41,7 +41,9 @@ bmap_help(void)
 " Holes are marked by replacing the startblock..endblock with 'hole'.\n"
 " All the file offsets and disk blocks are in units of 512-byte blocks.\n"
 " -a -- prints the attribute fork map instead of the data fork.\n"
+" -c -- prints the copy-on-write fork map instead of the data fork.\n"
 " -d -- suppresses a DMAPI read event, offline portions shown as holes.\n"
+" -e -- print delayed allocation extents.\n"
 " -l -- also displays the length of each extent in 512-byte blocks.\n"
 " -n -- query n extents.\n"
 " -p -- obtain all unwritten extents as well (w/ -v show which are unwritten.)\n"
@@ -75,6 +77,7 @@ bmap_f(
        int                     loop = 0;
        int                     flg = 0;
        int                     aflag = 0;
+       int                     cflag = 0;
        int                     lflag = 0;
        int                     nflag = 0;
        int                     pflag = 0;
@@ -85,12 +88,19 @@ bmap_f(
        int                     c;
        int                     egcnt;
 
-       while ((c = getopt(argc, argv, "adln:pv")) != EOF) {
+       while ((c = getopt(argc, argv, "acdeln:pv")) != EOF) {
                switch (c) {
                case 'a':       /* Attribute fork. */
                        bmv_iflags |= BMV_IF_ATTRFORK;
                        aflag = 1;
                        break;
+               case 'c':       /* CoW fork. */
+                       bmv_iflags |= BMV_IF_COWFORK | BMV_IF_DELALLOC;
+                       cflag = 1;
+                       break;
+               case 'e':
+                       bmv_iflags |= BMV_IF_DELALLOC;
+                       break;
                case 'l':       /* list number of blocks with each extent */
                        lflag = 1;
                        break;
@@ -113,7 +123,7 @@ bmap_f(
                        return command_usage(&bmap_cmd);
                }
        }
-       if (aflag)
+       if (aflag || cflag)
                bmv_iflags &= ~(BMV_IF_PREALLOC|BMV_IF_NO_DMAPI_READ);
 
        if (vflag) {
@@ -273,13 +283,14 @@ bmap_f(
 #define MINRANGE_WIDTH 16
 #define MINAG_WIDTH    2
 #define MINTOT_WIDTH   5
-#define NFLG           5       /* count of flags */
-#define        FLG_NULL        000000  /* Null flag */
-#define        FLG_PRE         010000  /* Unwritten extent */
-#define        FLG_BSU         001000  /* Not on begin of stripe unit  */
-#define        FLG_ESU         000100  /* Not on end   of stripe unit  */
-#define        FLG_BSW         000010  /* Not on begin of stripe width */
-#define        FLG_ESW         000001  /* Not on end   of stripe width */
+#define NFLG           6       /* count of flags */
+#define        FLG_NULL        0000000 /* Null flag */
+#define        FLG_SHARED      0100000 /* shared extent */
+#define        FLG_PRE         0010000 /* Unwritten extent */
+#define        FLG_BSU         0001000 /* Not on begin of stripe unit  */
+#define        FLG_ESU         0000100 /* Not on end   of stripe unit  */
+#define        FLG_BSW         0000010 /* Not on begin of stripe width */
+#define        FLG_ESW         0000001 /* Not on end   of stripe width */
                int     agno;
                off64_t agoff, bbperag;
                int     foff_w, boff_w, aoff_w, tot_w, agno_w;
@@ -350,6 +361,10 @@ bmap_f(
                        if (map[i + 1].bmv_oflags & BMV_OF_PREALLOC) {
                                flg |= FLG_PRE;
                        }
+                       if (map[i + 1].bmv_oflags & BMV_OF_SHARED)
+                               flg |= FLG_SHARED;
+                       if (map[i + 1].bmv_oflags & BMV_OF_DELALLOC)
+                               map[i + 1].bmv_block = -2;
                        /*
                         * If striping enabled, determine if extent starts/ends
                         * on a stripe unit boundary.
@@ -382,6 +397,14 @@ bmap_f(
                                        agno_w, "",
                                        aoff_w, "",
                                        tot_w, (long long)map[i+1].bmv_length);
+                       } else if (map[i + 1].bmv_block == -2) {
+                               printf("%4d: %-*s %-*s %*s %-*s %*lld\n",
+                                       i,
+                                       foff_w, rbuf,
+                                       boff_w, _("delalloc"),
+                                       agno_w, "",
+                                       aoff_w, "",
+                                       tot_w, (long long)map[i+1].bmv_length);
                        } else {
                                snprintf(bbuf, sizeof(bbuf), "%lld..%lld",
                                        (long long) map[i + 1].bmv_block,
@@ -413,6 +436,8 @@ bmap_f(
                }
                if ((flg || pflag) && vflag > 1) {
                        printf(_(" FLAG Values:\n"));
+                       printf(_("    %*.*o Shared extent\n"),
+                               NFLG+1, NFLG+1, FLG_SHARED);
                        printf(_("    %*.*o Unwritten preallocated extent\n"),
                                NFLG+1, NFLG+1, FLG_PRE);
                        printf(_("    %*.*o Doesn't begin on stripe unit\n"),

diff --git a/man/man8/xfs_bmap.8 b/man/man8/xfs_bmap.8
index e196559a1ae1410489a6ce1eaad3e6dae2c4d354..098cfae589f02ff045d6437742509eb6240ac83e 100644 (file)
--- a/man/man8/xfs_bmap.8
+++ b/man/man8/xfs_bmap.8
@@ -36,6 +36,10 @@ no matter what the filesystem's block size is.
 If this option is specified, information about the file's
 attribute fork is printed instead of the default data fork.
 .TP
+.B \-c
+If this option is specified, information about the file's
+copy on write fork is printed instead of the default data fork.
+.TP
 .B \-d
 If portions of the file have been migrated offline by
 a DMAPI application, a DMAPI read event will be generated to
@@ -45,6 +49,16 @@ printed.  However if the
 option is used, no DMAPI read event will be generated for a
 DMAPI file and offline portions will be reported as holes.
 .TP
+.B \-e
+If this option is used,
+.B xfs_bmap
+obtains all delayed allocation extents, and does not flush dirty pages
+to disk before querying extent data. With the
+.B \-v
+option, the
+.I flags
+column will show which extents have not yet been allocated.
+.TP
 .B \-l
 If this option is used, then
 .IP

diff --git a/man/man8/xfs_io.8 b/man/man8/xfs_io.8
index 2c56f09283253fda5533c79c4bbdb03f6691b8b8..d0895240d78033c851c2217aa65761718817f25f 100644 (file)
--- a/man/man8/xfs_io.8
+++ b/man/man8/xfs_io.8
@@ -256,7 +256,7 @@ See the
 .B pwrite
 command.
 .TP
-.BI "bmap [ \-adlpv ] [ \-n " nx " ]"
+.BI "bmap [ \-acdelpv ] [ \-n " nx " ]"
 Prints the block mapping for the current open file. Refer to the
 .BR xfs_bmap (8)
 manual page for complete documentation.